Treatment and survival of primary effusion lymphoma ( PEL ): A population‐based study among 25 patients diagnosed in the N etherlands between 2002 and 2015

Abstract

Introduction: PEL is an extremely rare, albeit devastating subtype of non‐Hodgkin lymphoma (NHL). Treatment information on PEL exclusively comes from the few available single‐center or multicenter studies with small, selected patient series. Therefore, information from a non‐selected group of patients at the population level is needed to complement those studies. Here, we report the outcomes of a nationwide population‐based study on treatment and survival among newly diagnosed patients with PEL in the Netherlands. Methods: We selected all patients diagnosed with PEL in the Netherlands between 2002 and 2015 from the nationwide Netherlands Cancer Registry (N = 25; median age, 53 years; range, 30‐81 years). Data on patient characteristics at diagnosis and treatment were available for individual patients. Overall survival (OS) and progression‐free survival (PFS) were calculated to assess patient outcome. Results: The majority of patients were male (88%) and HIV positive (76%). Prior Kaposi sarcoma was present in 28% of patients. None of the patients had prior Castleman disease. HIV‐negative PEL patients were older than HIV‐positive PEL patients (median age, 70 vs 49 years; P = 0.011). At the time of PEL diagnosis, 14 (74%) of 19 HIV‐positive patients were on highly active antiretroviral therapy (HAART). All patients had a lymphomatous effusion in ≥1 serous cavity, with pleural effusions being the most frequent (84%), followed by peritoneal (56%) and pericardial effusions (8%). Ten (40%) patients also had extracavitary localizations. Eight (28%) patients received no therapy. Of those who received first‐line therapy, CHOP or CHOP‐like regimens were most commonly applied (15/17; 82%), followed by one patient who received prednisone alone and one patient who initiated HAART alone. Three patients received CHOP with high‐dose methotrexate. Nine of 15 patients (60%) who received chemotherapy attained a complete or partial remission, of which 3 eventually relapsed. Four patients had progressive disease, and in 2, the response was unknown. Six patients received second‐line therapy, consisting of a variety of regimens. All 12 HIV‐positive patients who received firstline chemotherapy were on HAART. The median OS for the entire cohort was 7.6 months (Figure 1A). Nine (36%) patients are still alive. The median follow‐up for patients still alive is 26.2 (range, 8.9‐130.3) months. For 15 patients who received first‐line chemotherapy, the median PFS was 14.7 months (Figure 1B). Conclusion: This nationwide population‐based study shows that, in an era with contemporary HAART and well‐established NHL therapy, PEL is still associated with a poor prognosis. Nevertheless, it seems that prolonged survival can be achieved in selected patients who can attain and maintain a remission after chemotherapy. Information from population‐based studies can support clinical decision making in PEL. (Figure Presented).