Real-World Data Show High Rate of Second Cancers After Polycythemia Vera Diagnosis

More than one-third of patients with polycythemia vera (PV) reported at least one second primary cancer after PV diagnosis, according to retrospective data presented at the 65th ASH Annual Meeting and Exposition.

The most common second cancer was skin cancer, driven by non-melanoma skin cancers, according to study presenter Naveen Pemmaraju, MD, of the University of Texas MD Anderson Cancer Center.

Dr. Pemmaraju and colleagues conducted a retrospective study using electronic health record (EHR) data on 105 million U.S. patients with linked medical and prescription claims from 2007 to 2019. Of those patients, more than 82,000 had one or more PV diagnoses at any time.

For this retrospective study, the researchers included 20,089 patients with PV who had two or more PV diagnosis codes with 60 days or more between the first and last diagnosis code. Patients were indexed at the first diagnosis code of PV preceded by ≥1 year of EHR data and required ≥1 year of post-index data or death prior to data period end.

With a median duration of follow-up of 4.3 years, the researchers found that 35.7% of patients had at least one second cancer during the post-index period. The rate of second cancer during that period was 109.7 events per 1,000 patient years.

Skin cancer comprised the majority of second cancers, accounting for 22.1 events per 1,000 person years. It was followed by prostate cancer and breast cancer.

Of the patients with a second cancer, 9.1% reported at least one skin cancer, 8.3% with a non-melanoma skin cancer. Non-melanoma skin cancer diagnosis was sixfold more prevalent over melanoma.

Of the more than 20,000 patients included, 17,402 had pre-index medication data available. About one-fifth (20.2%) were treated with at least four weeks of hydroxyurea at any time, and about one-fifth (19.0%) were treated with phlebotomy.

Second cancer after hydroxyurea was 2.5 times more common than after phlebotomy (140.4 events vs 55.3 events per 1,000 person years; P<.0001). Rates of second skin cancers were twofold greater in the patients exposed to hydroxyurea compared with phlebotomy for any skin cancer (P<.0001), non-melanoma skin cancers (P<.0001), and melanoma (P=.0219).

Reference

Pemmaraju N, Markova A, Masarova L, et al. Prevalence of second cancers in patients with polycythemia vera (PV): a retrospective analysis of US real-world claims data. Abstract #3190. Presented at the 65th ASH Annual Meeting and Exposition; December 9-12, 2023; San Diego, California.