title: Prolonged response without prolonged chemotherapy: a lesson from PCV chemotherapy in low-grade gliomas.
abstract: Previous studies with temozolomide suggest that a prolonged duration of chemotherapy is important for treating low-grade gliomas (LGGs). PCV (procarbazine, CCNU, vincristine) chemotherapy has demonstrated efficacy in treating LGGs, but this therapy cannot be used for a prolonged period because of the cumulative toxicity. The aim of the present study was to evaluate the impact of first-line PCV chemotherapy on LGGs growth kinetics. The mean tumor diameter (MTD) of 21 LGGs was measured on serial magnetic resonance images before (n=13), during, and after PCV onset (n=21). During PCV treatment, a decrease in the MTD was observed in all patients. After PCV discontinuation, an ongoing decrease in MTD was observed in 20 of the 21 patients. Median duration of the MTD decrease was 3.4 years (range, 0.8-7.7) after PCV onset and 2.7 years (range, 0-7) after the end of PCV treatment with 60% of LGGs, demonstrating an ongoing and prolonged (>2 years) response despite chemotherapy no longer being administered. According to McDonald's criteria, the rates of partial and minor responses were 5% and 38% at the end of PCV but 38% and 42% at the time of maximal MTD decrease, which occurred after a median period of 3.4 years after PCV onset. These results challenge the idea that a prolonged duration of chemotherapy is necessary for treating LGGs and raise the issue of understanding the mechanisms involved in the persistent tumor volume decrease once chemotherapy is terminated.
authors.affiliation: Hôpital Neurologique de Lyon, 59 boulevard Pinel, 69677 Bron Cedex, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Peyre
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Cartalat-Carel
authors.forename: David
authors.initials: D
authors.lastname: Meyronet
authors.forename: Damien
authors.initials: D
authors.lastname: Ricard
authors.forename: Anne
authors.initials: A
authors.lastname: Jouvet
authors.forename: Johan
authors.initials: J
authors.lastname: Pallud
authors.forename: Karima
authors.initials: K
authors.lastname: Mokhtari
authors.forename: Jacques
authors.initials: J
authors.lastname: Guyotat
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Jouanneau
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Sunyach
authors.forename: Didier
authors.initials: D
authors.lastname: Frappaz
authors.forename: Jérôme
authors.initials: J
authors.lastname: Honnorat
authors.forename: François
authors.initials: F
authors.lastname: Ducray
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000473:pathology; D005260:Female; D005910:Glioma / Q000188:drug therapy* / Q000473:pathology; D006801:Humans; D008130:Lomustine / Q000008:administration & dosage / Q000627:therapeutic use; D008279:Magnetic Resonance Imaging; D008297:Male; D011344:Procarbazine / Q000008:administration & dosage / Q000627:therapeutic use; D012189:Retrospective Studies; D014750:Vincristine / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D011344:Procarbazine; D014750:Vincristine; D008130:Lomustine