Activity of Pemetrexed on brain metastases from Non-Small Cell Lung Cancer

Brain metastases from Non-Small Cell Lung Cancer are usually associated with poor prognosis and up to now chemotherapy has shown a modest activity upon cerebral localizations. We investigated the role of Pemetrexed, a new, well tolerated multi-target antifolate, on brain metastases.

We collected 39 patients with evidence of cerebral nervous system (CNS) localizations from Non-Small Cell Lung Cancer (NSCLC) before starting treatment with Pemetrexed as second-line or further-line therapy.

We confirmed the good tolerability of Pemetrexed even in that setting of patients and we reported a progressive disease (PD) in 12 patients (30.8%), a stable disease (SD) and partial response (PR) in 12 (30.8%) and 15 (38.4%) patients respectively, with an overall clinical benefit obtained in 69% of patients. The cerebral response to Pemetrexed was interesting with a cerebral radiological benefit obtained in 32 patients (82%), while 7 patients only showed brain progressive disease. Overall median survival was 10 months. All irradiation-naïve patients and those with clear radiological evidence of cerebral progression after brain radiotherapy and before Pemetrexed, overall 22 patients, were included in one group, in order to avoid overlapping effects between brain radiotherapy and Pemetrexed over CNS localizations. Within that setting, we demonstrated an overall clinical benefit (SD+PR) and cerebral benefit in 63% and 68%, of patients respectively. Distribution of patients by overall response to Pemetrexed and CNS response was highly suggestive of activity of Pemetrexed on brain metastases.

We demonstrated the good tolerability of Pemetrexed even in patients with advanced NSCLC and brain metastases, and we found a very good overall response rate with evidence of activity on brain localizations.