Secondary Malignancies in Patients with Primary Myelofibrosis

According to Utsav Joshi and collaborating researchers, it is unclear whether patients with primary myelofibrosis (PMF) have the increased risk for second primary malignancy (SPM) seen in other BCR-ABL-negative myeloproliferative diseases (MPD). In a study presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting, they reported that patients with PMF indeed have a higher risk for developing an SPM—especially leukemia and lymphoma.

Their study was based on 5,273 patients from the Surveillance, Epidemiology, and End Results (SEER) database with a diagnosis of PMF between 2009 and 2018. Any subsequent malignancy that presented after at least one year was classified as a SPM.

Among the study’s cohort, 342 patients (6.4%) developed a SPM. The authors calculated that SPM occurred at a standardized incidence ratio (SIR) of 1.97 (95% confidence interval [CI], 1.77–2.18; p <0.05) and with an absolute excess risk (AER) of 151.87 per 10,000 people. Notably, the incidences of melanoma (SIR = 1.96; 95% CI, 1.14–3.14; p <0.05), lymphoma (SIR = 3.45; 95% CI, 2.31–4.96; p <0.05), and leukemia (SIR = 26.87; 95% CI, 22.69–31.59; p <0.05) were significantly higher than other malignancies. Conversely, there were no statistically significant differences in SIR based on sex, race, marital status, follow-up duration, and receipt of chemotherapy.

Finally, SPM risk was significantly higher for patients aged ≤60 years (SIR = 2.34; 95% CI, 1.89–2.86) compared to patients aged >60 years (SIR = 1.86; 95% CI, 1.65–2.10; p = 0.01), as well as for patients with PMF diagnoses after 2009 (SIR = 2.64; 95% CI, 2.26–3.07) compared to during or before 2009 (SIR = 1.61; 95% CI, 1.40–1.85; p <0.001).

The researchers described an increased risk for SPM in patients with PMF, comparable to other MPD. In closing, the authors advanced the impact of the 2011 approval of ruxolitinib as a topic for further SPM research.