PCV for oligodendroglial tumors: In search of prognostic factors for response and survival

Background: We report survival and pretreatment prognostic factors for surv ival and chemosensitivity in 53 oligodendrogliomas treated with PCV (procar bazine, lomustine and vincristine) chemotherapy. Methods: A total of 53 pat ients with histologically proven oligodendroglioma, anaplastic oligodendrog lioma or oligo-astrocytoma and treated with PCV were extracted from the Lon don Regional Cancer Center database. A retrospective review was conducted t o evaluate overall survival and pretreatment prognostic factors for surviva l and chemosensitivity. Results: The median survival time from diagnosis wa s 123.6 months. The overall five- and ten-year survival rates were 72.7% an d 52.7% respectively. Age < 40, seizure as an initial symptom, absence of c ognitive deficit and presence of a homogeneous hypodense lesion without con trast enhancement on the initial pretreatment CT scan were all factors inde pendently associated with favorable outcome. The presence of increased cell ularity, pleomorphism, mitosis, vascular proliferation and grading as an an aplastic lesion using these surrogates on pathological assessment, were all associated with an unfavorable outcome in univariable. analysis. In multiv ariable analysis, only the anaplastic grading and presence of increased cel lularity were significant determinants of unfavorable survival. The only fa ctor adversely associated with chemosensitivity was the presence of a focal symptom at presentation. Conclusion: Overall survival is significantly lon ger in oligodendroglial lesions than in fibrillary astrocytic tumors. A two tier grading system using standard morphological features seems accurate i n predicting outcome in these patients. The presence of a neoplastic astroc ytic component does not seem to impact the outcome. No clinical, radiologic al or pathological factor could be identified to reliably predict chemother apy response.