TRENDS IN THE DEMOGRAPHICS, INCIDENCE, SOCIOECONOMIC STATUS, AND SURVIVAL IN PRIMARY EFFUSION LYMPHOMA: A SEER DATABASE ANALYSIS

SESSION TITLE: Complicated Pleural Effusions SESSION TYPE: Rapid Fire Original Inv PRESENTED ON: 10/10/2023 12:55 pm - 01:44 pm PURPOSE: Primary Effusion Lymphoma (PEL) is one of the lesser encountered AIDS-associated lymphomas, comprising ~4% of total cases. The purpose of this retrospective study is to analyze the epidemiology, to better understand this rare malignancy. METHODS: The data was collected from Surveillance, Epidemiology and End Result database Research Plus Data, 17 Registries, Nov 2021 Sub (2000-2019). We extracted PEL cases diagnosed after 20 years of age, using the site and morphology lymphoid neoplasm recode. The analysis was further completed on the prevalence, incidence rates, age distribution, sex predilection, role of socio-economic status, & survival of patients on chemotherapy, using the Log-rank test (GraphPad Prism). RESULTS: A total of 205 cases were identified. Of these, 88.29% were males, showing a strong prediliction. The median age at diagnosis was 51 years and median survival (mOS) was 6 months. Amongst the racial distribution of the current prevalence, Caucasians were most commonly affected (49.2%), followed by Hispanics (24,8%), African-Americans (21.4%), Asians and Pacific Islanders (2.9%) & the least affected were American Indians/Alaskan Natives (0.4%). Although, the most commonly affected population at present is caucasian, the incidence rate in African-Americans(1.23) was noted to be higher than that of the general population at 0.26 per 1,000,000 vs. that of whites, which has steadily declined to 0.07 per 1,000,000, as of 2019. Out of 205, only 57.5% patients received chemotherapy. Patients who recevived chemotherapy had significanlty better mOS vs. no chemotherapy (12 months vs 2 months, p <0.0001 (HR 0.5303, 95% CI of ratio 0.3790 to 0.7418). The distribution of the affected patients was unequal socioeconomiclly, with 67.80% belonging to a household with <$75,000/year. CONCLUSIONS: PEL is a rare type of lymphoma with only about 205 cases reported in between 2000-2019. It predominantly affects males over females. It is more common in white population, but its incidence is increasing in African- and reducing in whites. It is more prevalent in lower socioeconomic group. Only marginally more than half of the patients received chemotherapy. Despite chemotherapy, the survival is about 1 year, suggesting a poor prognosis. CLINICAL IMPLICATIONS: PEL is a rare B-cell lymphoma with an aggressive course. This condition affects people who are immunosuppressed. There is an association HHV8 in the literature. PEL is treated with regimens like DA-EPOCH (Dose adjusted etoposide phosphate, prednisone, vincristine sulfate (Oncovin), cyclophosphamide, and doxorubicin hydrochloride (hydroxydaunorubicin)and CHOP. This is the largest retrospective study done to analyze the epidemiology of this lesser understood rare malignancy and warrants further analysis to establish associations and treatment responses.It also highlights that physicians need to look for PEL, especially when the patient has an immunosupressed state like HIV when they present with a pleural effusion. DISCLOSURES: No relevant relationships by Bohdan Baralo No relevant relationships by Krishna Desai No relevant relationships by Sohiel Deshpande No relevant relationships by Sabah Iqbal No relevant relationships by Nithya Ramesh No relevant relationships by Rajesh Thirumaran