Impact of Karnovsky performance status (KPS) on outcome of elderly patients (pts) with glioblastoma (GBM) and activity of temozolomide (TMZ) as first line therapy: Retrospective analysis of a cohort

Abstract

1515 Background: Due to increasing incidence of GBM in the elderly, prognostic factors and therapeutic strategies need to be considered in this population. Recently radiotherapy has shown survival improvement in patients with KPS ≥ 70 (ANOCEF, EANO 2005), while chemotherapy with TMZ may be considered as a therapeutic option (Chinot at al, Cancer 2003). Methods: We analyzed retrospectively all pts above 70 years old with GBM, who were referred to our institution from May 1998 to October 2004; all responses to TMZ were reviewed. Results: We identified 136 pts registered. Median age was 74 (range 70–87), and 43% had a KPS < 70. Surgery consisted of stereotactic biopsy (SB), 29% ; partial surgery (PS), 12%; and gross total removal (GTR), 29% of pts. Diagnosis was strongly suggested by neuroradiology in 30% of cases. Treatment consisted of TMZ (5 days standard schedule) (group A) as first-line treatment in 89 pts (65%), radiotherapy and/or nitroso-urea based regimens in 40 pts (30%) (group B) and best supportive care in 7 (5%) pts. For the all cohort, median of overall survival (OS) was 7 months (m), strongly impacted by KPS (3.9 vs 8.7 m, p<0.0001 for KPS < 70 and ≥70 respectively) and age (8.2 vs 6.0 m, p<0.007 for age < 75 years vs. ≥ 75). OS was 6.6, 7.3, and 8.4 mos in the case of SB, PS, and GTR respectively and was 5.2 for neuroradiologic diagnosis. In group A, median time to tumour progression (TTP) and OS were 4.7 & 7.3 m. KPS impacted TTP (2.9 vs. 5.1 m, p=0.0002) and OS (4.9 vs. 8.7 m, p<0.0001) for KPS < and ≥ 70 respectively. Response rates (RR) were for 71 pts evaluable 28%; SD 35%; PD 37% associated with an OS of 11.7, 7 and 3.2 m respectively. RR was 34% for histologically proven GBM, vs 22% in cases of neuroradiologic diagnosis. In group B, TTP and OS were 4.3 & 6.7 m respectively. Conclusions: KPS appeared to have a major impact on outcomes in elderly patients with GBM. Future trials designs should take this impact into consideration. TMZ appeared to be effective in elderly patients with newly diagnosed GBM. This alternative approach is currently being tested against RT alone in international trials. Impact of MGMT status in the TMZ population will be presented. No significant financial relationships to disclose.