P02PRIMARY CENTRAL NERVOUS SYSTEM LYMPHOMA (PCNSL) IN THE CEREBELLUM: REPORT OF TWO RARE CASES AND A TEN YEAR MULTI-CENTRE REVIEW OF PCNSL

INTRODUCTION: Primary central nervous system lymphoma (PCNSL) is a malignant tumour. Its incidence is 0.46-0.51/100000/year. Cerebellar PCNSL is rare. Previously documented cases included only snapshots of the radiological appearances in large PCNSL series; therefore the radiological progression of cerebellar PCNSL has not been described. We report 2 cases of solitary cerebellar lymphoma, followed by a 10-year review of PCNSLs in our region. METHOD: Report of 2 rare cases with radiological emphasis; retrospective multi-centre review. Patients diagnosed with PCNSL in Jan 2002 - Dec 2011 were identified in the West Midlands Cancer Intelligence Unit registry. Retrospective analyses of survival associated with age, sex and treatment were carried out. RESULTS: 153 patients were diagnosed. The incidence is 0.28/100000/year. None of them was cerebellar lesion. The 2 cases described occurred after Dec 2011. The mean age was 63 years. 101 patients (66%) were >60 years old. The M:F ratio was 1.25. Survival in patients >60 years was significantly less than ≤60 years (3.3 and 18 mth, respectively). Survival was longest in patients receiving both chemo- and radiotherapy (52 pt, 26.9 mth), followed by either chemo- or radiotherapy (28 pt, 3.1 mth and 38 pt, 3.0 mth) and least in those receiving none (35 pt, 1.3 mth). CONCLUSION: We report 2 rare cases of cerebellar PCNSL and described the rapid radiological transformation. The 10 year review of PCNSL confirmed its poor prognosis and showed that maximal therapy is associated with better survival.