Analysis of Patient-Reported Outcomes of Patients With MF or ET in the MOST Study

A recent study evaluated patient-reported outcomes (PROs) using data from the Myelofibrosis and Essential Thrombocythemia Observational Study (MOST). The aim of the study was to analyze the patient-reported symptom burden and its effect on these patients’ activity, work productivity, and quality of life (QoL) to help improve disease management and treatment strategies (Leukemia & Lymphoma. 2022;63[13]:3138-3153. doi:10.1080/10428194.2022.2113531).

PROs can provide data that are important and difficult to obtain about a patient’s perception of their physical, social, and psychological well-being, according to Ellen Ritchie, MD, Weill Cornell Medical College, New York, NY, and colleagues. However, there is limited PRO data available on the effects of symptom burden on QoL for both the lower risk myelofibrosis (MF) and between high- and low-risk essential thrombocythemia (ET) populations. There is also limited existing data on evaluating the level of success of ET-directed treatment for relieving symptom burden in these patients.

For their study, Dr Ritchie and colleagues used data from the MOST study, which consisted of patients from 124 US academic and community sites. Of these patients, 125 (53.6%) had MF and 801 (64.9%) had ET and had completed at least one PRO assessment, which qualified them for the study. The researchers obtained the PRO data at the time of patient enrollment in MOST (between November 2016 and March 2019 for patients with MF and between November 2016 and December 2018 for patients with ET) and during usual-care visits over 36 months.

In order for patients to be eligible for the study, they needed to meet the following additional criteria for the MF cohort: ≥18 years old, diagnosed with MF (including primary MF, post-polycythemia vera MF, and post-ET MF), and categorized as low risk or INT-1 risk by reason of age alone per the Dynamic International Prognostic Scoring System. For the ET cohort, patients were required to have high-risk ET (≥60 years old and/or a history of thrombotic events) or have low-risk ET while currently receiving ET-directed therapy (not including aspiring only).

As part of the study, the patients completed questionnaires at the time of their enrollment in MOST and every 6 months at follow-up appointments. To assess the patient-reported symptom burden, the authors used the Myeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (TSS). The questionnaires covered 10 symptom categories, including fatigue, abdominal discomfort, bone pain, and weight loss. Patients rated the severity of the symptoms on a 0 to 10 scale, with scores ≥7 considered severe, scores 4 to 6 considered moderate, scores of 1 to 3 considered mild, and 0 considered none.

To evaluate health-related QoL, the researchers used the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (v3). The questionnaire contained 30 items organized into five multi-item functional scales, including physical, emotional, and social; three multi-item symptom scales, including pain, fatigue, and nausea and vomiting; one multi-item global health/QoL scale; and six additional single-symptom items, including dyspnea, constipation, and financial difficulties.

The patients were provided with four response options for each of these items: not at all, a little, quite a bit, and very much. Additional response options, ranging from very poor to excellent, were provided for the global health-status/QoL scale. If the patients had higher scores on the symptom scale, that indicated a higher symptom burden, while higher scores on the functional and global health/QoL scale demonstrated higher functioning and better health/QoL.

Overall, the study found that myeloproliferative neoplasm–related symptoms have a significant impact on the QoL of patients with MF/ET, even those symptoms that are considered less severe. In both the MF and ET cohorts, fatigue was identified as the most common and severe symptom (21.7% for patients with MF and 17% for patients with ET). Also, for both cohorts, women reported higher mean (SD) TSS than men: 20.4 (15.8) vs 16.0 (14.2), P > .05; and 18.4 (15.8) vs 14.2 (14.9), P < .01, for women with MF and ET, respectively. Women also reported higher mean symptom scores and reduced QoL compared to men. In patients with MF, high symptom burden was similar in both low- and INT-1–risk patients. For patients with low-risk ET, higher mean TSS and symptom scores were reported compared to patients with high-risk ET.

The authors note that the main limitation of the study was that the majority of patients enrolled were White, which could potentially lead to reporting bias in the clinical outcomes and PROs due to a lack of inclusion of underrepresented US populations.

“[P]atients with lower risk MF and low- or high-risk ET experience significant symptom burden that affects QoL and ability to work,” wrote the authors. They suggest that the results from their study provide evidence that symptom burden among patients with MF or ET should be further investigated and strategies to reduce symptom burden should be included when treating these patients.

“The observed higher symptom burden perceived by women compared with men suggests that gender could play an important role in the presentation of MF and ET and should be incorporated into disease management decisions,” Ritchie and colleagues added.