Three-Year Follow-Up of a Randomized Phase II Trial on Refinement of Early-Stage NSCLC Adjuvant Chemotherapy with Cisplatin and Pemetrexed versus Cisplatin and Vinorelbine (the TREAT Study)

Abstract

Introduction: Adjuvant chemotherapy in non-small cell lung cancer (NSCLC) improves survival but is associated with significant toxicity. The Randomized Phase II Trial on Refinement of Early-Stage NSCLC Adjuvant Chemotherapy with Cisplatin and Pemetrexed versus Cisplatin and Vinorelbine (TREAT study) was designed to test the hypothesis that a protocol with reduced toxicity might improve feasibility of postoperative delivery of adjuvant chemotherapy drugs to patients with NSCLC, thereby improving compliance and, potentially, survival.

Methods: Two adjuvant regimens were evaluated for feasibility in 132 patients with NSCLC: the standard regimen of cisplatin and vinorelbine (CVb) (cisplatin 50 mg/m(2) on day 1 and day 8 and vinorelbine 25 mg/m(2) on days 1, 8, 15, and 22 every 4 weeks) and a regimen consisting of cisplatin and pemetrexed (CPx) (cisplatin 75 mg/m(2) and pemetrexed 500 mg/m(2) on day 1 every 3 weeks). The primary end-point analysis showing that CPx is safe and feasible with dose delivery superior to that of CVb has already been published. Here we report the 3-year follow-up results of the secondary efficacy end points-overall, relapse-free, distant metastasis-free, and local relapse-free survival-also with regard to histologic diagnosis.

Results: After a median of 39 months, no significant differences in any of the outcome parameters between CVb and CPx were observed. Also, histologic diagnosis and tumor size in stage IB did not influence survival in the CPx-treated patients. Yet, Cox regression analyses showed that overall survival at 3 years was significantly correlated with feasibility and the occurrence of dose-limiting toxicity.

Conclusions: Although adjuvant chemotherapy with CPx is safe and characterized by less toxicity and better dose delivery than CVb, overall survival was not influenced by treatment arm in the context of this phase II trial.

Keywords: Adjuvant chemotherapy; Non–small cell lung cancer; Outcome; Pemetrexed; Toxicity.