We treated patients with newly diagnosed and large low-grade oligodendroglial tumors with upfront procarbazine, CCNU and vincristine (PCV) in order to delay radiotherapy. Patients were treated with PCV for a maximum of 6 cycles. The response to treatment was defined according to the RANO criteria; in addition change over time of mean tumor diameters (growth kinetics) was calculated. Thirty-two patients were treated between 1998 and 2006, 18 of which were diagnosed with 1p/19q co-deleted tumors. Median follow-up duration was 8 years (range 0.5–13 years). The median overall survival (mOS) was 120 months and the median progression-free survival (mPFS) was 46 months. Growth kinetics showed an ongoing decrease of the mean tumor diameter after completion of chemotherapy, during a median time of 35 months, but an increase of the mean tumor diameter did not herald progression as detected by RANO criteria. 1p/19q co-deletion was associated with a significant increase in OS (mOS 83 months versus not reached for codeleted tumors; p = 0.003)) and PFS (mPFS 35 months versus 67 months for codeleted tumors; p = 0.024). Patients with combined 1p/19q loss had a 10 year PFS of 34 % and the radiotherapy in these patients was postponed for a median period of more than 6 years. This long-term follow-up study indicates that upfront PCV chemotherapy is associated with long PFS and OS and delays radiotherapy for a considerable period of time in patients with low-grade oligodendroglial tumors, in particular with combined 1p/19q loss.

Chemotherapy, Low-grade glioma, Oligo-astrocytoma, Oligodendroglioma, Tumor growth kinetics
dx.doi.org/10.1007/s11060-014-1641-9, hdl.handle.net/1765/85428
Journal of Neuro-Oncology
Department of Neurology

Taal, W, van der Rijt, C.C.D, Dinjens, W.N.M, Sillevis Smitt, P.A.E, Wertenbroek, A.A.A.C.M, Bromberg, J.E.C, … van den Bent, M.J. (2015). Treatment of large low-grade oligodendroglial tumors with upfront procarbazine, lomustine, and vincristine chemotherapy with long follow-up: a retrospective cohort study with growth kinetics. Journal of Neuro-Oncology, 121(2), 365–372. doi:10.1007/s11060-014-1641-9