Diagnostic Dilemma: Nonhealing Ulcer in a Diabetic Foot

Department Editor: Tania Phillips, MD, FRCPC Overall Learning Objective: The physician or podiatrist participant will develop a rational approach to the evaluation and treatment of a variety of uncommon wounds and will have an increased awareness of the differential diagnosis of cutaneous wounds and the systemic diseases associated with these wounds. Submissions: To submit a case for consideration in Diagnostic Dilemmas, e-mail or write to: Executive Editor, WOUNDS, 83 General Warren Blvd., Suite 100, Malvern, PA 19355, eklumpp@hmpcommunications.com Completion Time: The estimated time to completion for this activity is 1 hour. Target Audience: This CME/CPME activity is intended for dermatologists, surgeons, podiatrists, internists, and other physicians who treat wounds. At the conclusion of this activity, the participant should be able to: 1. List the most common conditions associated with Marjolin’s ulcers 2. Identify the best means of diagnosing a Marjolin’s ulcer 3. Identify the most accepted standard treatment of a Marjolin’s ulcer of the foot. Disclosure: All faculty participating in Continuing Medical Education programs sponsored by The North American Center for Continuing Medical Education are expected to disclose to the meeting audience any real or apparent conflict(s) of interest related to the content of their presentation. Drs. Christopher, Li, Gonzalez, Valiulis, Cunningham, and McCulloch disclose that they have no financial conflicts relevant to the content of this activity. Accreditation: This activity is sponsored by the North American Center for Continuing Medical Education (NACCME). NACCME is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The North American Center for Continuing Medical Education is approved by the Council on Podiatric Medical Education as a sponsor of continuing education in podiatric medicine. Designation: NACCME designates this continuing medical education activity for 1 credit hour in Category 1 of the Physician’s Recognition Award of the American Medical Association. Each physician should claim only those hours he/she spent in the educational activity. NACCME designates this continuing medical activity for .1 CEUs available to participating podiatrists. Method of Participation: Participants must read the article and take, submit, and pass the post-test by June 15, 2005. Participants must completely fill out the answer and evaluation form, answer at least 70 percent of the questions correctly, and mail or fax the answer/evaluation forms to: Trish Levy, CME Director, NACCME, HMP Communications Suite 100, 83 General Warren Blvd., Malvern, PA 19355 Fax (610) 560-0501 This activity has been planned and produced in accordance with the ACCME Essential Areas and Policies. Release date: June15, 2004 Expiration date: June 15, 2005 Introduction A 66-year-old Black man with type 2 diabetes, hypertension, chronic renal insufficiency, and peripheral vascular disease was referred from the community to the Physical Therapy Wound Care Clinic at Louisiana State University Health Sciences Center. The patient had sustained a scald burn to the entire right foot in 1985. His initial treatment of his burn wound included excision and split-thickness grafting of the dorsum of the foot, while the plantar surface was allowed to heal by secondary intention. According to the patient, the wound on the dorsum healed well, but the plantar wound did not. Two years post burn, the patient underwent a left below-knee amputation due to peripheral vascular disease. This made healing of his plantar wound more unlikely due to his dependence upon his right foot. Over the course of fifteen years, various therapies and topical applications were utilized to promote healing without success. At the time of his referral to Physical Therapy, he had an ulcer on the plantar surface of his right foot measuring 28cm2 (Figure 1). The ulcer was covered with adherent fibrinous exudate and bled easily. The margins of the wound were hypertrophic. Dorsalis pedis and posterior tibial pulses were not palpable. There was a 2+ pitting edema to mid-calf. The ulcer was classifed as I-C based on the University of Texas wound classification system.[1] Initial therapy consisted of cleansing with pulsatile lavage with suction followed by the application of a semipermeable foam dressing. The patient was fitted with a heel wedge to offweight the ulcer. Concerned at the patient’s lack of response to conventional therapies and the extreme duration of the ulcer, the physical therapist requested an evaluation by the plastic surgeons in the Diabetic Limb and Wound Care Clinic. Surgical Evaluation On initial evaluation in the Diabetic Limb and Wound Care Clinic, plain radiographs were obtained, which demonstrated a mildly sclerotic appearance of the calcaneus but no periosteal reaction to suggest osteomyelitis. The patient’s diabetes was under good control with a HbA1c of 7.4 percent. The surgeon determined that surgical debridement with incisional biopsies and cultures were indicated. Intraoperative pathology was returned as skin with hyperkeratosis, parakeratosis, and pseudoepitheliomatous hyperplasis. Cultures were positive for Proteus mirabilis, Staphylococcus aureas (methicillin sensitive), Corynebacterium species, Porphyromonas species, and Bacteroides fragilis. The patient was started on culture-specific antimicrobial therapy. A second debridement was performed on postoperative Day 10 and additional biopsies were obtained. Diagnosis Biopsies were returned as squamous cell carcinoma (Marjolin’s ulcer). A subsequent metastatic evaluation was performed, which was negative. Discussion Malignant degeneration of burn scars has been recognized since the early 19th century. Jean Nicholas Marjolin first desbribed an indolent ulcer arising in a burn scar in 1828.[2] However, it was R. W. Smith, in 1850, who first recognized the malignant potential of these ulcers and DaCosta, in 1903, who first used the term Marjolin’s ulcer to describe malignant degeneration of chronic leg ulcers.[3] Today, the term Marjolin’s ulcer is used to refer to an epidermoid carcinoma arising in a burn scar or other chronically irritated tissue, including venous insufficiency ulcers, pressure ulcers, osteomyelytic sinuses, fistulae, traumatic wounds, systostomy sites, or scarring from lupus.[4–10] These cancers are usually squamous cell, but may be basal cell or melanoma.[11,12] While the exact cause of Marjolin’s ulcers is not known, there is strong evidence to support the belief that chronic irritation is a major factor leading to the initiation of carcinoma.8 Inflammation and repeated trauma, especially in flexion creases, may provide enough chronic irritation to promote malignant change. Biopsy is the definitive diagnostic tool. Bewkwits, et al.,[13] and Lawrence[14] suggest that specimens be taken from both the center and the margins of suggestive lesions. This is certainly supported in this case where initial biopsy failed to provide a definitive diagnosis. Treatment will vary depending upon the type of carcinoma identified. Most clinicians agree that appropriate treatment of a Marjolin’s ulcer that is basal or squamous cell carcinoma and is confined to the skin involves a wide local excision with a margin of at least one centimeter of healthy tissue. In these cell types, amputation is only recommended when excision is complicated by such things as deep invasion, bone or joint involvement, extensive infection, hemorrhage, or where there would be a resultant impairment of function.[8,15] This patient suffered a burn in 1985, and his plantar wound never healed. Over a 15-year period of time, his lack of healing was attributed to the fact that he had diabetes, had peripheral vascular disease, and was bearing excessive weight on the wound due to his contralateral lower-extremity amputation. The question that arises is at what point should one become suspicious of malignancy in a diabetic ulcer, whether it be from burn or other trauma? Are there visual indicators of malignant transformation? Should all ulcers be biopsied? Or should only those ulcers be biopsied that do not respond to the usual techniques after a certain period of time? In this particular case, an experienced wound care practitioner realized that this was a highly unusual presentation of a diabetic foot wound and that further medical evaluation was indicated. There is no documented case of malignant transformation of a diabetic foot ulcer in the literature, though the insensate limb could certainly be predisposed to such an ulcer due to repetitive trauma. Thermal burns are common in people with diabetes due to sensory neuropathy and loss of protective sensation but also due to the patient’s constant cold sensation of their feet. In this case, the burn wound never did heal completely. Treatment The patient was offered treatment options and decided to seek a second opinion from an outside surgeon. Under the care of that surgeon, the patient underwent a right below-knee amputation. Pathologic evaluation revealed squamous cell carcinoma, predominantly grade 2 with foci of grade 3 tumor. No vascular angioinvasion was noted. At present, the patient is four months post-op without evidence of recurrence or metastasis and is ambulating on bilateral below-knee prostheses. Long-term follow up is recommended; however, as Ames and Hickey have reported, 98 percent of all recurrences occur within three years of excision.[16] Questions 1. Marjolin’s ulcers have been associated with all of the following situations except A. Old burn scars B. Venous insufficiency ulcers C. Osteomyelitis D. Diabetic foot ulcerations 2. The most common form of cancer seen with Marjolin's ulcers is: A. Squamous cell carcinoma B. Basal cell carcinoma C. Melanoma D. Fibrosarcoma 3. Diagnosis of Marjolin’s ulcer is best achieved with: A. Plain film radiographpy B. T-cell count C. Wound biopsy D. Lymph node biopsy 4. Long-term follow-up suggests that 98 percent of all recurrences of Marjolin’s ulcers occurs within: A. 1 year B. 3 years C. 5 years D. 7 years 5. One of the most accepted factors causing the development of carcinoma in Marjolin’s ulcers is: A. Prolonged exposure of the tissues to chronic wound fluid B. Chemical irritation from abuse of topical agents C. Untreated osteomyelitis D. Chronic irritation of the tissue from inflammation and repeated trauma 6. The most accepted standard treatment for a Marjolin’s ulcer of the foot that is squamous or basal cell carcinoma and is confined to the skin is: A. Amputation of the involved extremity B. Local excision with a margin of at least 1cm of healthy tissue C. Local excision with lymph node dissection D. Local tissue irradiation 7. When performing a biopsy of a suspected Marjolin’s ulcer, it is recommended that sampling be done from which area(s)? A. The center of the lesion B. The advancing margins C. An area of substantial necrotic tissue D. A central and peripheral area Nonhealing Ulcer in a Diabetic Foot Answer and Evaluation Form Please print clearly: Name Degree Position/Title Organization/Institute Department Mailing Address for Certificate (H or W): City State Zip Code Email Address Social Security Number Phone (area code) Fax (area code) Answers (Refer to questions on other side of page) Circle ONE letter for each answer: 1. A B C D 2. A B C D 3. A B C D 4. A B C D 5. A B C D 6. A B C D 7. A B C D Evaluation (circle one): Excellent (4) Good (3) Satisfactory (2) Poor (1) Accuracy and timeliness of content: 4 3 2 1 Relevance to your daily practice: 4 3 2 1 Impact on your professional effectiveness: 4 3 2 1 Relevance of the content to the learning objectives: 4 3 2 1 Effectiveness of the teaching/learning methods: 4 3 2 1 This activity avoided commercial bias or influence YES NO Now that you have read this article, can you: 1. List the most common conditions associated with Marjolin’s ulcers? YES NO 2. Identify the best means of diagnosing a Marjolin’s ulcer? YES NO 3. Identify the most accepted standard treatment of a Marjolin’s ulcer of the foot? YES NO What questions do you still have?_______________________________________ How will you use what you have learned from this activity?____________________ All tests must be received by 6/15/05.