Management and Outcomes of Plasmablastic Lymphoma: A Single-Center Experience

Background: Plasmablastic lymphoma (PBL) is a rare aggressive B-cell neoplasm characteristically occurring in patients with HIV infection. Given their rarity, most of the existing literature is from case reports or heterogenous pooled data. Optimal therapy is not clearly defined and outcomes are traditionally poor with median survival in the order of months. We describe the epidemiology, management and outcomes of this rare malignancy at a single center.

Methods: We identified patients with PBL diagnosed between 2000- 2015 at Parkland Memorial Hospital. Patients were followed till June 2015. Structured forms were used to interview patients and to abstract relevant (demographics, diagnostics, pathology, therapy and outcomes) clinical data. Logistic regression was used to assess variables for association with the odds of treatment failure. Log-rank test was used to assess differences in survival by treatment regimen. Statistical analysis was performed using SAS software version 9.0 (SAS Institute).

Results: Twenty-nine patients with PBL were diagnosed in the study period. Median age at presentation was 42 years; 24 (83%) were male.  Twenty-sex (90%) occurred in patients with HIV infection; median CD4+ count at diagnosis was 93 /mm3; median viral load was 97,823 copies/ mL. Only 5 patients (17%) were actively taking antiretroviral therapy at the time of diagnosis. Three patients were immunocompetent. The most common primary site of disease was the gastrointestinal tract (13 patients) followed by oral/maxillofacial sites (10 patients). Twenty patients (69%) presented with adanced stage disease (stage III or IV disease). EBV was detected in all 26 cases where it was tested; HHV-8 was negative in all patients. CD20 positivity was seen in only 4 patients (14%). MYC rearrangements were described in 70% patients. EPOCH (etoposide, prednisolone, vincristine, cyclophosphamide and hydroxydaunorubicin), was the most common treatment regimen used in 16 patients (56%). Radiation therapy was administered in 28% of patients. Overall survival across the cohort was 9.9 months. Twenty patients (69%) died during the follow-up period; their median survival was 2.6 months. Nine patients were alive after a median follow-up of 47.8 months. Those who were treated with EPOCH demonstrated a better median overall survival compared to those who were not (26.3 months vs 1.2 months, p value 0.01). 

Conclusions: PBL is a rare AIDS-related lymphoma most commonly affecting the oral cavity and gastrointestinal tract. It mostly occurs in HIV patients not on HAART. Patients usually present with advanced stage disease. OS continues to be poor but EPOCH regimens can improve survival compared to non-EPOCH regimens, and should be further explored in this setting.