ABCL-179 Primary Cranial Vault Lymphoma: Review of Cases Diagnosed at a General Hospital

Context: Primary cranial vault lymphoma (PCVL) is a rare type of non-Hodgkin lymphoma arising outside the brain parenchyma without evidence of systemic disease. Diffuse large B cell lymphoma (DLBCL) is the most common histological subtype of PCVL. Objective: The main objective of this study was to analyze the outcome of patients with PCVL at our institution. Design: Single-center, retrospective study. Setting: We reviewed patients with PCVL at Memorial Hermann Hospital, Texas Medical Center between 2013 and 2021. Patients or Other Participants: Three patients with PCVL were identified. Interventions: Patients were treated with standard rituximab-based chemoimmunotherapy and radiotherapy. Main Outcome Measures: We analyzed the clinical presentation, objective response to treatment, rate of complete remission, and long-term clinical outcomes of patients with PCVL. Results: Three cases (women=2, men=1) of PCVL were identified. Subject races were Hispanic (n=2) and Black (n=1). Mean age was 74 years. Two patients presented with a skull mass, and the third presented with disequilibrium, frequent falls, left-hand weakness, numbness, and forgetfulness. Positron emission tomography did not reveal any evidence of systemic disease, and bone marrow biopsy was negative in all 3 cases. Two patients underwent craniotomy and resection of the periosteal mass, whereas one patient with a scalp mass underwent diagnostic biopsy. Pathology showed DLBCL in all three cases, and fluorescent in situ hybridization showed an absence of C-MYC, Bcl-2, or Bcl-6 translocations. The Ki-67 proliferative index was noted to be high (70%–80%) in all 3 cases. One patient received 6 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone), and another received 6 courses of dose-adjusted R-EPOCH (rituximab, etoposide, prednisone, oncovin, cyclophosphamide, and doxorubicin). Both of these patients received consolidative radiotherapy and remain in complete remission (CR) for 3 and 9 years. The third patient (80 years old) received postoperative radiotherapy at a dose of 40 Gy delivered in 20 fractions. All three achieved and remain in complete remission for 3 years, 9 years, and 7 months, respectively. Conclusions: PCVL is a rare lymphoproliferative neoplasm with favorable long-term outcomes. It responds well to chemoimmunotherapy and radiotherapy. Timely recognition of this rare entity can avoid unnecessary surgical intervention.