Can Time from Last Chemotherapy to Recurrence be a Predictor of Chemosensitivity in Rcurrent Globlastoma

ABSTRACT Purpose Since temozolomide in combination with radiotherapy (RT/TMZ) became a new standard for newly diagnosed glioblastoma, the scenario at recurrence became less defined. Moreover, the role of prognostic and predictive factors for the second treatment has not been clarified. Methods A retrospective analysis was made for glioblastoma patients followed between 01/2005 and 06/2010. Eligibility criteria for the study were: age ≥18 years; PS:0-2; chemotherapy at disease progression after RT/TMZ, availability of data regarding second progression. Results 232 patients with recurrent glioblastoma (mean age: 52 years, range: 18-77years, MGMT methylated/unmethylated: 62 [37.6%] / 103 [62.4%]) were evaluated. At progression after RT/TMZ, 102 patients (44%) were treated with surgery followed by chemotherapy, and 130 patients (56%) with chemotherapy alone. Chemotherapy consisted in TMZ rechallenge 5/28 in 80 patients (34%), nitrosoureas in 120 patients (52%), experimental treatments in 32 patients (14%). PFS-6 calculated from 1st to 2nd PD was 22% (95%CI:16.3-26.9%). Time from the last adjuvant TMZ treatment to recurrence (TTR) was shorter in patients treated with nitrosoureas (2.6 months) than in patients treated with TMZ (9.8 months, p  Conclusions As in other cancer types (i.e. ovarian cancer), TTR seems to be promising as a predictive factor for PFS obtained with treatments for recurrence and could be useful in patients' stratification. TMZ rechallenge seems more useful than nitrosoureas if TTR is longer. Disclosure All authors have declared no conflicts of interest.