Treatment outcomes and survival in patients with primary central nervous system lymphomas treated between 1995 and 2010 – a single center report
Primary central nervous system lymphomas (PCNSL) are rare variants of extranodal non-Hodgkin¢s lymphomas that are nowadays primarily treated with high-dose methotrexate or methotrexate-based chemotherapy with or without radiation therapy. The optimal treatment of PCNSL is still unknown and there are differences in clinical practice. With this retrospective research we evaluated our series of patients with PCNSL in regards to the patient¢s characteristics, treatment results, disease specific survival and overall survival. Fifty nine patients who attended the Institute of Oncology Ljubljana between 1995 and 2010 were treated according to the protocol that was valid at the time of patient¢s admission. Between 1995 and 1999, systemic treatment was classical CHOP (cyclophosphamide, doxorubicin, vincristine, steroids) chemotherapy, and later on high-dose methotrexate either alone or in combination with other agents. From 1999 onwards, radiation therapy was applied according to patient¢s age and response to chemotherapy, prior to that all patients treated with CHOP were also irradiated. Patients ineligible for systemic treatment were treated with sole radiation therapy. There was a strong female predominance in our series and the median age at diagnosis was 59,8 years. Patients had predominantly aggressive B cell lymphomas (69,5%), one patient had marginal cell lymphoma and two patients T cell lymphoma. In total, 20,3% of patients were treated just with chemotherapy, 33,9% with combined therapy and 42,4% with sole radiation therapy. The overall response rate to primary treatment in patients treated with sole chemotherapy was 33,3%, in patients treated with combined therapy 65% and in patients treated only with radiation therapy 56%, respectively. In terms of response duration, significantly better results were achieved with combined therapy or radiation therapy alone compared to sole chemotherapy (p<0,0006). The median overall survival of the whole cohort was 11 months and the overall survival was significantly affected by patient¢s age. The longest overall survival was observed in patients treated with combined therapy (median survival of 39 months). Patients treated just with radiation therapy had a median overall survival of 9 months and those treated with sole chemotherapy of 4,5 months, respectively. In conclusion, the treatment outcomes in ordinary clinical practice are definitely inferior to the ones reported in clinical trials. The now standard treatment with high-dose methotrexate with or without radiation therapy is sometimes too aggressive and therefore a careful selection on the basis of patient¢s age, performance status and concomitant diseases of those eligible for such treatment is mandatory. According to our results, radiation therapy should not be excluded from the primary treatment.