Cutaneous “lumps and bumps” are common presenting problems in pediatric dermatology. In part one of this two-part series, an approach will be outlined for the most common lesions as well as those that can be challenging to manage.
Nevus Sebaceous of Jadassohn (NS)
Nevus sebaceous is typically a congenital hamartoma that appears on the scalp and face, usually as a solitary lesion. It often has a linear configuration. The lesions look different depending on their stage. At birth the lesions may be prominent, owing to maternal hormonal stimulation of the sebaceous components of these lesions.1 During childhood, NS often looks underdeveloped.2 During puberty, as sebaceous glands become active, the lesion may become veruccous and more prominent. These lesions pose three potential problems that will be outlined below.
Nevus sebaceous associated with systemic findings. NS is typically an isolated lesion, although rare systemic associations — especially neurologic — are well recognized. Often, this is considered in cases of extensive NS. Davies, et al.,3 reviewed neurological manifestations in 196 patients with NS and found 93% neurologically normal. Of those with neurological abnormalities, only 21% had extensive NS. Five percent of patients with NS who were normal neurologically had extensive NS. The centrofacial location for NS was more often seen in those who had neurological abnormalities and, if reproducible in other studies, may be a useful marker for associated disease. Given that neurological abnormalities were seen even in those without extensive NS, it is reasonable for all patients presenting with NS to have a neurological history and exam. Any patient demonstrating neurological abnormalities should be considered for neuroimaging. Referral to a pediatrician or neurologist may be needed.
Risk of development of neoplasms. Managing this potential risk is one of the most contentious issues in the management of NS. It is well established that both benign and malignant neoplasms can arise from NS. However, the magnitude of the risk for malignant lesions is controversial and thus the decision of when or if to excise NS prophylactically is a challenging one. Some of the discrepancy in risk from different authors may be that some non-malignant lesions arising within NS have been incorrectly diagnosed as malignant.4 Basal cell carcinoma (BCC) is thought to be the most frequent among malignant growths although other carcinomas have been reported.4,5
Cribier et al4 conducted a large retrospective review of 596 NS cases, of which 232 were children at the time of excision. There was a total of 13.6% benign neoplasms. The two most frequent lesions were syringocystadenoma papilliferum and trichoblastoma. Many of the trichoblastomas were originally read as BCCs but on reappraisal met the criteria for trichoblastoma. Basal cell carcinoma was the only malignant neoplasm reported, at a rate of 0.8% (5/596). Most of the benign lesions (63/81) and all of the BCCs were located on the scalp. Less than 2% of NS in children showed benign lesions, and no instances of BCC were found in children. Santibanez et al2 found no cases of BCC in 658 pathology samples of NS in a retrospective review of NS patients less than 16 years of age.
While rare reports of BCC arising in NS have occurred in children,6 the above large series highlight the rarity of BCC in NS, particularly in children.
Given that the risk of malignant neoplasms is rare in NS, several management options are reasonable. Small lesions could be observed lifelong and biopsied or removed if they show change. Given the low risk of changes prior to puberty and the need for a general anesthetic in younger patients, prophylactic removal could also be undertaken, but it might be reasonable to wait until puberty when removal with local anesthetic is possible. Large lesions, which are often a cosmetic problem, may need to be addressed earlier.
Cosmetic Concerns. Large lesions on the scalp or facial lesions may indeed pose cosmetic problems for children. Small lesions that are not prominent during childhood may become a bigger concern during adolescence when the lesions thicken and when appearance generally becomes increasingly important. The decision to remove a lesion for cosmetic reasons should be undertaken in conjunction with the parents and patient with attention to issues such as anesthesia, scar and the degree of impact the lesion is having on the child’s self-esteem. Often delaying the removal of small lesions until the child is older may allow use of local anesthesia only.
Pilomatricoma
Pilomatricoma (PMC) is a benign growth of cells of the hair follicle, including cortex, inner sheath and matrix cells.7 It typically presents as a slow-growing, subcutaneous, blue, very firm mass.7,8 Pain or tenderness is seen in about one-third of patients.8 Stretching the skin over the nodule and revealing multiple facets and angles (the “tent sign”) is a helpful diagnostic finding.9 PMCs are usually de novo but have been reported in previous areas of injury.8 Mutations in beta-catenin have been found in many PMC cases.10,11 B-catenins are proteins involved in the cytoskeleton, normal cell growth and signaling pathways.7
While it can occur at any age, PMC is considered more common in children. Pirouzmanesh,8 in a large review of pediatric PMC, found 88% occurred before the age of 10. Ming, et al., found 45% of cases occurred in those under age 18. PMC has a female preponderance.7,8 It commonly occurs on the head, neck and upper extremities.7,12 Typically, PMC is a solitary lesion. Multiple PMCs have been associated with a variety of other features such as myotonic dystrophy (Steinert disease).7
This is a lesion that is often misdiagnosed as an epidermal cyst or dermoid cyst.8,12 Clinical diagnosis with confirmation on histopathology is generally all that is required. Diagnostic imaging is rarely needed but may be required preoperatively if the resection of the lesion is in a difficult anatomic region.8
The treatment of choice is surgical excision and recurrence is rare.7,12
Pyogenic Granuloma
Pyogenic granulomas (PGs), or lobular capillary hemangiomas, are relatively common lesions. Patients typically present because of concern about cosmetic appearance or, more often, because of repeated bleeding and crusting. Typically they are erythematous, dome-shaped papules that often bleed and then develop crusting. Pagliai, et al.,13 found that 84% of PG had a history of bleeding at the time of presentation. Antecedent trauma is often considered an inciting event. However, 77% of patients in this study showed no history of predisposing trauma or predisposing lesions.13 While it is unclear what causes PGs, hormonal or angiogenic factors may play a role as they are common in pregnancy and have been reported to arise in pre-existing vascular lesions. Pagliai found 8.7% of the total PGs in the study arose in a hemangioma or a port wine stain. The most common location was on the head and neck (77%). Lesions are most likely to be solitary although, rarely, multiple lesions have been reported.13
Other lesions may mimic PGs such as hemangiomas, warts, glomus tumors or Spitz nevi.14 Often the history and clinical exam will help differentiate between these. Few lesions develop as rapidly as PGs. The rare lesions that mimic PGs might support a need to remove all for histology. However, keep in mind that for treatment some of the destructive modalities are successful.
Treatment options. Approximately 5% of patients may show spontaneous regression without treatments although it may take 6 to 18 months.13 While this suggests no treatment might be an option, in reality the lesions that frequently bleed and crust are probably best treated. Parents often report difficulty stopping the bleeding, so waiting for months for self-resolution may not be practical.
A variety of treatment options have been used including: excision and electrocautery, CO2 laser, pulsed dye laser, punch excision or cryotherapy.13 Pagliai found that those lesions treated with excision and electrocautery had no recurrence. )f those treated with laser, 50% had persistent or recurrent lesions. It could be that the lesions treated with CO2 laser were more complicated.13 Moon et al15 found sclerotherapy to be successful and well tolerated in adults. Up to five treatments were needed but most had complete resolution with rare scarring.
A study comparing cryotherapy and curettage for PG, which included children, showed no statistical difference regarding treatment success.16 For the cryotherapy group, 63% cleared with one treatment and 32% required two treatments for clearance. Five percent required three treatments. Curettage followed by electrodesiccation cleared 97% with one treatment and 3% of the patients required two treatments. No recurrence was seen in any patient. The cosmetic outcome was not statistically different between the two groups. Curettage with a 97% cure would be comparable with surgical excision but with a smaller scar and less disruption of normal tissue.16 Scarring — textural or color change — was seen in many patients treated with one of the above methods. Interestingly, only 25% of those whose PGs spontaneously regressed showed any scarring.
First-line treatment for removing PGs could be curettage with electrodesiccation as this allows for histologic confirmation of diagnosis, smaller scar than excision, good cosmetic outcome and successful elimination of the lesion usually in one treatment. However, there may be situations (e.g., a struggling toddler with a lesion near the eye), where cryotherapy may be quicker and easier.
Juvenile Xanthogranulomas
Juvenile xanthogranuloma (JXG) is also a relatively common lesion seen by pediatric dermatologists. Confusion exists with respect to its classification, risk of systemic associations and how to manage that risk. Typically, JXGs appear as yellow, soft lesions17 and often have telangiectasia. They typically occur in the skin but are well-documented to occur in subcutaneous fat, muscle and organs.17 They usually occur singly.
JXGs often self-resolve in several years and may leave residual atrophy or pigmentation.18,19 When lesions are removed for diagnosis or treatment, recurrence is uncommon but does occur.17
Nature of the lesion. JXGs are collections of histiocytes and fall into the non-Langerhan cell histiocytoses. It was recently highlighted in the literature that JXG likely represents a spectrum of conditions with similar lineage and cell markers that clinically may look distinct.18 Differentiating JXG from Langerhan cell histiocytosis (LCH) is an important distinction to make. An early JXG may be difficult to distinguish clinically and histologically. Immunohisto-chemistry will show Langerhan’s cells are S-100 and CD1a positive whereas the histiocytes of JXG will show positivity with monocyte/macrophage markers such as Ki-M1P or CD-68.17
Systemic Associations. Multiple lesions are more likely to be associated with organ involvement than solitary lesions. Organs most likely to be involved are: brain, liver, kidney, lung, heart and small intestine.17 These findings were in patients for whom workup was undertaken. It is possible that the rate of internal lesions is higher, but if asymptomatic, they’ll go unnoticed.
Eye involvement, particularly the iris, is not an uncommon extracutaneous finding.20,21 Sixty-nine percent of dermatologists routinely send JXG patients for eye exams.20 However, an eye exam may not be required routinely, as a review of the literature and survey of management practices suggests that eye lesions tend to occur in children less than 2 years old (92%), tend to be associated with multiple skin JXGs and that patients usually present to an ophthalmologist for acute eye findings.20 The overall incidence of eye involvement in pediatric patients in several series combined is 0.4%.20
An association of JXGs and neurofibromatosis 1 (NF1) has been clearly established.19 In fact, Cambiaghi has proposed that presence of JXG and multiple café-au-lait macules may be an excellent marker for NF1 in the absence of other diagnostic signs of NF1. The origin of the association is unclear. There are reports about a third association with JXG, NF1 and juvenile chronic myelogenous leukemia (JCML) all occurring together.22 Reports of the triad certainly occur, but the magnitude of risk is unclear. Cambiaghi followed patients with JXG and NF and no patient developed JCML,19 although it was a small study and follow-up was variable.
Management of JXGs. JXGs can often be diagnosed clinically from their appearance as soft, yellow papules. When they look more nodular, brown or indistinct, a biopsy/excision will often confirm the diagnosis. Immunohistochem-istry can help distinguish JXG from LCH when histology is equivocal.
JXGs will usually resolve on their own and removal is not always necessary. A history and exam to rule out systemic involvement and NF1 will usually be sufficient with workup reserved for those with findings.
Regarding the need for eye exam in asymptomatic patients, a reasonable guideline might be to have those patients under 2 years of age with multiple lesions routinely examined.
Recognizing Important Pediatric Diseases
When patients present with common lumps and bumps, it’s important to be able to distinguish and diagnose which condition the patient has so that appropriate treatment can be started.
In the second-part of this series, we’ll explore other common conditions that present in pediatric patients.
Cutaneous “lumps and bumps” are common presenting problems in pediatric dermatology. In part one of this two-part series, an approach will be outlined for the most common lesions as well as those that can be challenging to manage.
Nevus Sebaceous of Jadassohn (NS)
Nevus sebaceous is typically a congenital hamartoma that appears on the scalp and face, usually as a solitary lesion. It often has a linear configuration. The lesions look different depending on their stage. At birth the lesions may be prominent, owing to maternal hormonal stimulation of the sebaceous components of these lesions.1 During childhood, NS often looks underdeveloped.2 During puberty, as sebaceous glands become active, the lesion may become veruccous and more prominent. These lesions pose three potential problems that will be outlined below.
Nevus sebaceous associated with systemic findings. NS is typically an isolated lesion, although rare systemic associations — especially neurologic — are well recognized. Often, this is considered in cases of extensive NS. Davies, et al.,3 reviewed neurological manifestations in 196 patients with NS and found 93% neurologically normal. Of those with neurological abnormalities, only 21% had extensive NS. Five percent of patients with NS who were normal neurologically had extensive NS. The centrofacial location for NS was more often seen in those who had neurological abnormalities and, if reproducible in other studies, may be a useful marker for associated disease. Given that neurological abnormalities were seen even in those without extensive NS, it is reasonable for all patients presenting with NS to have a neurological history and exam. Any patient demonstrating neurological abnormalities should be considered for neuroimaging. Referral to a pediatrician or neurologist may be needed.
Risk of development of neoplasms. Managing this potential risk is one of the most contentious issues in the management of NS. It is well established that both benign and malignant neoplasms can arise from NS. However, the magnitude of the risk for malignant lesions is controversial and thus the decision of when or if to excise NS prophylactically is a challenging one. Some of the discrepancy in risk from different authors may be that some non-malignant lesions arising within NS have been incorrectly diagnosed as malignant.4 Basal cell carcinoma (BCC) is thought to be the most frequent among malignant growths although other carcinomas have been reported.4,5
Cribier et al4 conducted a large retrospective review of 596 NS cases, of which 232 were children at the time of excision. There was a total of 13.6% benign neoplasms. The two most frequent lesions were syringocystadenoma papilliferum and trichoblastoma. Many of the trichoblastomas were originally read as BCCs but on reappraisal met the criteria for trichoblastoma. Basal cell carcinoma was the only malignant neoplasm reported, at a rate of 0.8% (5/596). Most of the benign lesions (63/81) and all of the BCCs were located on the scalp. Less than 2% of NS in children showed benign lesions, and no instances of BCC were found in children. Santibanez et al2 found no cases of BCC in 658 pathology samples of NS in a retrospective review of NS patients less than 16 years of age.
While rare reports of BCC arising in NS have occurred in children,6 the above large series highlight the rarity of BCC in NS, particularly in children.
Given that the risk of malignant neoplasms is rare in NS, several management options are reasonable. Small lesions could be observed lifelong and biopsied or removed if they show change. Given the low risk of changes prior to puberty and the need for a general anesthetic in younger patients, prophylactic removal could also be undertaken, but it might be reasonable to wait until puberty when removal with local anesthetic is possible. Large lesions, which are often a cosmetic problem, may need to be addressed earlier.
Cosmetic Concerns. Large lesions on the scalp or facial lesions may indeed pose cosmetic problems for children. Small lesions that are not prominent during childhood may become a bigger concern during adolescence when the lesions thicken and when appearance generally becomes increasingly important. The decision to remove a lesion for cosmetic reasons should be undertaken in conjunction with the parents and patient with attention to issues such as anesthesia, scar and the degree of impact the lesion is having on the child’s self-esteem. Often delaying the removal of small lesions until the child is older may allow use of local anesthesia only.
Pilomatricoma
Pilomatricoma (PMC) is a benign growth of cells of the hair follicle, including cortex, inner sheath and matrix cells.7 It typically presents as a slow-growing, subcutaneous, blue, very firm mass.7,8 Pain or tenderness is seen in about one-third of patients.8 Stretching the skin over the nodule and revealing multiple facets and angles (the “tent sign”) is a helpful diagnostic finding.9 PMCs are usually de novo but have been reported in previous areas of injury.8 Mutations in beta-catenin have been found in many PMC cases.10,11 B-catenins are proteins involved in the cytoskeleton, normal cell growth and signaling pathways.7
While it can occur at any age, PMC is considered more common in children. Pirouzmanesh,8 in a large review of pediatric PMC, found 88% occurred before the age of 10. Ming, et al., found 45% of cases occurred in those under age 18. PMC has a female preponderance.7,8 It commonly occurs on the head, neck and upper extremities.7,12 Typically, PMC is a solitary lesion. Multiple PMCs have been associated with a variety of other features such as myotonic dystrophy (Steinert disease).7
This is a lesion that is often misdiagnosed as an epidermal cyst or dermoid cyst.8,12 Clinical diagnosis with confirmation on histopathology is generally all that is required. Diagnostic imaging is rarely needed but may be required preoperatively if the resection of the lesion is in a difficult anatomic region.8
The treatment of choice is surgical excision and recurrence is rare.7,12
Pyogenic Granuloma
Pyogenic granulomas (PGs), or lobular capillary hemangiomas, are relatively common lesions. Patients typically present because of concern about cosmetic appearance or, more often, because of repeated bleeding and crusting. Typically they are erythematous, dome-shaped papules that often bleed and then develop crusting. Pagliai, et al.,13 found that 84% of PG had a history of bleeding at the time of presentation. Antecedent trauma is often considered an inciting event. However, 77% of patients in this study showed no history of predisposing trauma or predisposing lesions.13 While it is unclear what causes PGs, hormonal or angiogenic factors may play a role as they are common in pregnancy and have been reported to arise in pre-existing vascular lesions. Pagliai found 8.7% of the total PGs in the study arose in a hemangioma or a port wine stain. The most common location was on the head and neck (77%). Lesions are most likely to be solitary although, rarely, multiple lesions have been reported.13
Other lesions may mimic PGs such as hemangiomas, warts, glomus tumors or Spitz nevi.14 Often the history and clinical exam will help differentiate between these. Few lesions develop as rapidly as PGs. The rare lesions that mimic PGs might support a need to remove all for histology. However, keep in mind that for treatment some of the destructive modalities are successful.
Treatment options. Approximately 5% of patients may show spontaneous regression without treatments although it may take 6 to 18 months.13 While this suggests no treatment might be an option, in reality the lesions that frequently bleed and crust are probably best treated. Parents often report difficulty stopping the bleeding, so waiting for months for self-resolution may not be practical.
A variety of treatment options have been used including: excision and electrocautery, CO2 laser, pulsed dye laser, punch excision or cryotherapy.13 Pagliai found that those lesions treated with excision and electrocautery had no recurrence. )f those treated with laser, 50% had persistent or recurrent lesions. It could be that the lesions treated with CO2 laser were more complicated.13 Moon et al15 found sclerotherapy to be successful and well tolerated in adults. Up to five treatments were needed but most had complete resolution with rare scarring.
A study comparing cryotherapy and curettage for PG, which included children, showed no statistical difference regarding treatment success.16 For the cryotherapy group, 63% cleared with one treatment and 32% required two treatments for clearance. Five percent required three treatments. Curettage followed by electrodesiccation cleared 97% with one treatment and 3% of the patients required two treatments. No recurrence was seen in any patient. The cosmetic outcome was not statistically different between the two groups. Curettage with a 97% cure would be comparable with surgical excision but with a smaller scar and less disruption of normal tissue.16 Scarring — textural or color change — was seen in many patients treated with one of the above methods. Interestingly, only 25% of those whose PGs spontaneously regressed showed any scarring.
First-line treatment for removing PGs could be curettage with electrodesiccation as this allows for histologic confirmation of diagnosis, smaller scar than excision, good cosmetic outcome and successful elimination of the lesion usually in one treatment. However, there may be situations (e.g., a struggling toddler with a lesion near the eye), where cryotherapy may be quicker and easier.
Juvenile Xanthogranulomas
Juvenile xanthogranuloma (JXG) is also a relatively common lesion seen by pediatric dermatologists. Confusion exists with respect to its classification, risk of systemic associations and how to manage that risk. Typically, JXGs appear as yellow, soft lesions17 and often have telangiectasia. They typically occur in the skin but are well-documented to occur in subcutaneous fat, muscle and organs.17 They usually occur singly.
JXGs often self-resolve in several years and may leave residual atrophy or pigmentation.18,19 When lesions are removed for diagnosis or treatment, recurrence is uncommon but does occur.17
Nature of the lesion. JXGs are collections of histiocytes and fall into the non-Langerhan cell histiocytoses. It was recently highlighted in the literature that JXG likely represents a spectrum of conditions with similar lineage and cell markers that clinically may look distinct.18 Differentiating JXG from Langerhan cell histiocytosis (LCH) is an important distinction to make. An early JXG may be difficult to distinguish clinically and histologically. Immunohisto-chemistry will show Langerhan’s cells are S-100 and CD1a positive whereas the histiocytes of JXG will show positivity with monocyte/macrophage markers such as Ki-M1P or CD-68.17
Systemic Associations. Multiple lesions are more likely to be associated with organ involvement than solitary lesions. Organs most likely to be involved are: brain, liver, kidney, lung, heart and small intestine.17 These findings were in patients for whom workup was undertaken. It is possible that the rate of internal lesions is higher, but if asymptomatic, they’ll go unnoticed.
Eye involvement, particularly the iris, is not an uncommon extracutaneous finding.20,21 Sixty-nine percent of dermatologists routinely send JXG patients for eye exams.20 However, an eye exam may not be required routinely, as a review of the literature and survey of management practices suggests that eye lesions tend to occur in children less than 2 years old (92%), tend to be associated with multiple skin JXGs and that patients usually present to an ophthalmologist for acute eye findings.20 The overall incidence of eye involvement in pediatric patients in several series combined is 0.4%.20
An association of JXGs and neurofibromatosis 1 (NF1) has been clearly established.19 In fact, Cambiaghi has proposed that presence of JXG and multiple café-au-lait macules may be an excellent marker for NF1 in the absence of other diagnostic signs of NF1. The origin of the association is unclear. There are reports about a third association with JXG, NF1 and juvenile chronic myelogenous leukemia (JCML) all occurring together.22 Reports of the triad certainly occur, but the magnitude of risk is unclear. Cambiaghi followed patients with JXG and NF and no patient developed JCML,19 although it was a small study and follow-up was variable.
Management of JXGs. JXGs can often be diagnosed clinically from their appearance as soft, yellow papules. When they look more nodular, brown or indistinct, a biopsy/excision will often confirm the diagnosis. Immunohistochem-istry can help distinguish JXG from LCH when histology is equivocal.
JXGs will usually resolve on their own and removal is not always necessary. A history and exam to rule out systemic involvement and NF1 will usually be sufficient with workup reserved for those with findings.
Regarding the need for eye exam in asymptomatic patients, a reasonable guideline might be to have those patients under 2 years of age with multiple lesions routinely examined.
Recognizing Important Pediatric Diseases
When patients present with common lumps and bumps, it’s important to be able to distinguish and diagnose which condition the patient has so that appropriate treatment can be started.
In the second-part of this series, we’ll explore other common conditions that present in pediatric patients.
Cutaneous “lumps and bumps” are common presenting problems in pediatric dermatology. In part one of this two-part series, an approach will be outlined for the most common lesions as well as those that can be challenging to manage.
Nevus Sebaceous of Jadassohn (NS)
Nevus sebaceous is typically a congenital hamartoma that appears on the scalp and face, usually as a solitary lesion. It often has a linear configuration. The lesions look different depending on their stage. At birth the lesions may be prominent, owing to maternal hormonal stimulation of the sebaceous components of these lesions.1 During childhood, NS often looks underdeveloped.2 During puberty, as sebaceous glands become active, the lesion may become veruccous and more prominent. These lesions pose three potential problems that will be outlined below.
Nevus sebaceous associated with systemic findings. NS is typically an isolated lesion, although rare systemic associations — especially neurologic — are well recognized. Often, this is considered in cases of extensive NS. Davies, et al.,3 reviewed neurological manifestations in 196 patients with NS and found 93% neurologically normal. Of those with neurological abnormalities, only 21% had extensive NS. Five percent of patients with NS who were normal neurologically had extensive NS. The centrofacial location for NS was more often seen in those who had neurological abnormalities and, if reproducible in other studies, may be a useful marker for associated disease. Given that neurological abnormalities were seen even in those without extensive NS, it is reasonable for all patients presenting with NS to have a neurological history and exam. Any patient demonstrating neurological abnormalities should be considered for neuroimaging. Referral to a pediatrician or neurologist may be needed.
Risk of development of neoplasms. Managing this potential risk is one of the most contentious issues in the management of NS. It is well established that both benign and malignant neoplasms can arise from NS. However, the magnitude of the risk for malignant lesions is controversial and thus the decision of when or if to excise NS prophylactically is a challenging one. Some of the discrepancy in risk from different authors may be that some non-malignant lesions arising within NS have been incorrectly diagnosed as malignant.4 Basal cell carcinoma (BCC) is thought to be the most frequent among malignant growths although other carcinomas have been reported.4,5
Cribier et al4 conducted a large retrospective review of 596 NS cases, of which 232 were children at the time of excision. There was a total of 13.6% benign neoplasms. The two most frequent lesions were syringocystadenoma papilliferum and trichoblastoma. Many of the trichoblastomas were originally read as BCCs but on reappraisal met the criteria for trichoblastoma. Basal cell carcinoma was the only malignant neoplasm reported, at a rate of 0.8% (5/596). Most of the benign lesions (63/81) and all of the BCCs were located on the scalp. Less than 2% of NS in children showed benign lesions, and no instances of BCC were found in children. Santibanez et al2 found no cases of BCC in 658 pathology samples of NS in a retrospective review of NS patients less than 16 years of age.
While rare reports of BCC arising in NS have occurred in children,6 the above large series highlight the rarity of BCC in NS, particularly in children.
Given that the risk of malignant neoplasms is rare in NS, several management options are reasonable. Small lesions could be observed lifelong and biopsied or removed if they show change. Given the low risk of changes prior to puberty and the need for a general anesthetic in younger patients, prophylactic removal could also be undertaken, but it might be reasonable to wait until puberty when removal with local anesthetic is possible. Large lesions, which are often a cosmetic problem, may need to be addressed earlier.
Cosmetic Concerns. Large lesions on the scalp or facial lesions may indeed pose cosmetic problems for children. Small lesions that are not prominent during childhood may become a bigger concern during adolescence when the lesions thicken and when appearance generally becomes increasingly important. The decision to remove a lesion for cosmetic reasons should be undertaken in conjunction with the parents and patient with attention to issues such as anesthesia, scar and the degree of impact the lesion is having on the child’s self-esteem. Often delaying the removal of small lesions until the child is older may allow use of local anesthesia only.
Pilomatricoma
Pilomatricoma (PMC) is a benign growth of cells of the hair follicle, including cortex, inner sheath and matrix cells.7 It typically presents as a slow-growing, subcutaneous, blue, very firm mass.7,8 Pain or tenderness is seen in about one-third of patients.8 Stretching the skin over the nodule and revealing multiple facets and angles (the “tent sign”) is a helpful diagnostic finding.9 PMCs are usually de novo but have been reported in previous areas of injury.8 Mutations in beta-catenin have been found in many PMC cases.10,11 B-catenins are proteins involved in the cytoskeleton, normal cell growth and signaling pathways.7
While it can occur at any age, PMC is considered more common in children. Pirouzmanesh,8 in a large review of pediatric PMC, found 88% occurred before the age of 10. Ming, et al., found 45% of cases occurred in those under age 18. PMC has a female preponderance.7,8 It commonly occurs on the head, neck and upper extremities.7,12 Typically, PMC is a solitary lesion. Multiple PMCs have been associated with a variety of other features such as myotonic dystrophy (Steinert disease).7
This is a lesion that is often misdiagnosed as an epidermal cyst or dermoid cyst.8,12 Clinical diagnosis with confirmation on histopathology is generally all that is required. Diagnostic imaging is rarely needed but may be required preoperatively if the resection of the lesion is in a difficult anatomic region.8
The treatment of choice is surgical excision and recurrence is rare.7,12
Pyogenic Granuloma
Pyogenic granulomas (PGs), or lobular capillary hemangiomas, are relatively common lesions. Patients typically present because of concern about cosmetic appearance or, more often, because of repeated bleeding and crusting. Typically they are erythematous, dome-shaped papules that often bleed and then develop crusting. Pagliai, et al.,13 found that 84% of PG had a history of bleeding at the time of presentation. Antecedent trauma is often considered an inciting event. However, 77% of patients in this study showed no history of predisposing trauma or predisposing lesions.13 While it is unclear what causes PGs, hormonal or angiogenic factors may play a role as they are common in pregnancy and have been reported to arise in pre-existing vascular lesions. Pagliai found 8.7% of the total PGs in the study arose in a hemangioma or a port wine stain. The most common location was on the head and neck (77%). Lesions are most likely to be solitary although, rarely, multiple lesions have been reported.13
Other lesions may mimic PGs such as hemangiomas, warts, glomus tumors or Spitz nevi.14 Often the history and clinical exam will help differentiate between these. Few lesions develop as rapidly as PGs. The rare lesions that mimic PGs might support a need to remove all for histology. However, keep in mind that for treatment some of the destructive modalities are successful.
Treatment options. Approximately 5% of patients may show spontaneous regression without treatments although it may take 6 to 18 months.13 While this suggests no treatment might be an option, in reality the lesions that frequently bleed and crust are probably best treated. Parents often report difficulty stopping the bleeding, so waiting for months for self-resolution may not be practical.
A variety of treatment options have been used including: excision and electrocautery, CO2 laser, pulsed dye laser, punch excision or cryotherapy.13 Pagliai found that those lesions treated with excision and electrocautery had no recurrence. )f those treated with laser, 50% had persistent or recurrent lesions. It could be that the lesions treated with CO2 laser were more complicated.13 Moon et al15 found sclerotherapy to be successful and well tolerated in adults. Up to five treatments were needed but most had complete resolution with rare scarring.
A study comparing cryotherapy and curettage for PG, which included children, showed no statistical difference regarding treatment success.16 For the cryotherapy group, 63% cleared with one treatment and 32% required two treatments for clearance. Five percent required three treatments. Curettage followed by electrodesiccation cleared 97% with one treatment and 3% of the patients required two treatments. No recurrence was seen in any patient. The cosmetic outcome was not statistically different between the two groups. Curettage with a 97% cure would be comparable with surgical excision but with a smaller scar and less disruption of normal tissue.16 Scarring — textural or color change — was seen in many patients treated with one of the above methods. Interestingly, only 25% of those whose PGs spontaneously regressed showed any scarring.
First-line treatment for removing PGs could be curettage with electrodesiccation as this allows for histologic confirmation of diagnosis, smaller scar than excision, good cosmetic outcome and successful elimination of the lesion usually in one treatment. However, there may be situations (e.g., a struggling toddler with a lesion near the eye), where cryotherapy may be quicker and easier.
Juvenile Xanthogranulomas
Juvenile xanthogranuloma (JXG) is also a relatively common lesion seen by pediatric dermatologists. Confusion exists with respect to its classification, risk of systemic associations and how to manage that risk. Typically, JXGs appear as yellow, soft lesions17 and often have telangiectasia. They typically occur in the skin but are well-documented to occur in subcutaneous fat, muscle and organs.17 They usually occur singly.
JXGs often self-resolve in several years and may leave residual atrophy or pigmentation.18,19 When lesions are removed for diagnosis or treatment, recurrence is uncommon but does occur.17
Nature of the lesion. JXGs are collections of histiocytes and fall into the non-Langerhan cell histiocytoses. It was recently highlighted in the literature that JXG likely represents a spectrum of conditions with similar lineage and cell markers that clinically may look distinct.18 Differentiating JXG from Langerhan cell histiocytosis (LCH) is an important distinction to make. An early JXG may be difficult to distinguish clinically and histologically. Immunohisto-chemistry will show Langerhan’s cells are S-100 and CD1a positive whereas the histiocytes of JXG will show positivity with monocyte/macrophage markers such as Ki-M1P or CD-68.17
Systemic Associations. Multiple lesions are more likely to be associated with organ involvement than solitary lesions. Organs most likely to be involved are: brain, liver, kidney, lung, heart and small intestine.17 These findings were in patients for whom workup was undertaken. It is possible that the rate of internal lesions is higher, but if asymptomatic, they’ll go unnoticed.
Eye involvement, particularly the iris, is not an uncommon extracutaneous finding.20,21 Sixty-nine percent of dermatologists routinely send JXG patients for eye exams.20 However, an eye exam may not be required routinely, as a review of the literature and survey of management practices suggests that eye lesions tend to occur in children less than 2 years old (92%), tend to be associated with multiple skin JXGs and that patients usually present to an ophthalmologist for acute eye findings.20 The overall incidence of eye involvement in pediatric patients in several series combined is 0.4%.20
An association of JXGs and neurofibromatosis 1 (NF1) has been clearly established.19 In fact, Cambiaghi has proposed that presence of JXG and multiple café-au-lait macules may be an excellent marker for NF1 in the absence of other diagnostic signs of NF1. The origin of the association is unclear. There are reports about a third association with JXG, NF1 and juvenile chronic myelogenous leukemia (JCML) all occurring together.22 Reports of the triad certainly occur, but the magnitude of risk is unclear. Cambiaghi followed patients with JXG and NF and no patient developed JCML,19 although it was a small study and follow-up was variable.
Management of JXGs. JXGs can often be diagnosed clinically from their appearance as soft, yellow papules. When they look more nodular, brown or indistinct, a biopsy/excision will often confirm the diagnosis. Immunohistochem-istry can help distinguish JXG from LCH when histology is equivocal.
JXGs will usually resolve on their own and removal is not always necessary. A history and exam to rule out systemic involvement and NF1 will usually be sufficient with workup reserved for those with findings.
Regarding the need for eye exam in asymptomatic patients, a reasonable guideline might be to have those patients under 2 years of age with multiple lesions routinely examined.
Recognizing Important Pediatric Diseases
When patients present with common lumps and bumps, it’s important to be able to distinguish and diagnose which condition the patient has so that appropriate treatment can be started.
In the second-part of this series, we’ll explore other common conditions that present in pediatric patients.
