Primary central nervous system lymphoma in immunocompetent patients: A regional cancer center experience

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a rare form of aggressive extranodal non-Hodgkin's lymphoma which occurs in both immunocompromised and immunocompetent patients. It has an overall poor prognosis in spite of a multimodality treatment approach including chemotherapy and radiotherapy. This study attempts to further delineate the clinicopathological, immunohistochemical, and radiological profile of PCNSL at Kidwai Memorial Institute of Oncology, Karnataka, India. MATERIALS AND METHODS: All the pathologically confirmed PCNSL cases between January 2010 and June 2016, at our center, were analyzed retrospectively. The influence of potential prognostic parameters on overall survival (OS) was investigated by log-rank test and Cox regression analysis. RESULTS: Of the 26 PCNSL patients, 17 (65.3%) were males. Median age at diagnosis was 42.5 years. None of the patients had HIV or Epstein-Barr virus positivity and only four patients (15.4%) had B-symptoms. The most common location in the brain was cerebral hemispheres in 15 patients (57%) and 10 patients (38.5%) had multiple intracranial lesions. Histologically, all were diffuse large B-cell lymphomas, except one case of anaplastic large cell lymphoma. Immunohistochemically, 18 patients (69%) had MUM 1 positivity and 20 cases (77%) belonged to nongerminal center subtype. DeAngelis protocol was followed in 24 patients (92%), and among this cohort, Memorial Sloan Kettering Cancer Center Class 1 (n = 17) and Class 2 (n = 7) patients had a median OS of 25 months and 11 months, respectively. CONCLUSION: None of the potential prognostic factors had a statistically significant influence on OS in our patients. High-dose methotrexate combined with radiation is an effective therapeutic approach. However, further prospective studies with a large number of patients are needed to identify more effective primary chemotherapy regimens to further improve the treatment outcome.