Neoadjuvant chemotherapy (NACT) is the standard of care in non-small cell lung cancers (NSCLC) with locally advanced N2 disease. There is scarcity of data for pemetrexed-platinum regimen as NACT. Also, aside from N2 disease, role of NACT in locally advanced NSCLCs for tumor downstaging is unclear.
Nonmetastatic adenocarcinomas of lung treated with pemetrexed-platinum based NACT were analysed. The patients with locoregionally advanced N2 disease and those who were borderline candidates for upfront definitive treatment were planned for NACT after discussion in a multidisciplinary clinic. Total 4 cycles of 3-weekly pemetrexed and platinum were delivered in combined neoadjuvant and adjuvant setting. Response assessment was done using RECIST criteria. Progression free (PFS) and overall survival (OS) were calculated using Kaplan Meier method.
Out of 114 evaluable patients, 99 patients received NACT with pemetrexed-platinum. Most common indication for NACT was N2 disease at baseline (46.4%). Objective response rate was 38.2% (95% CI: 23%-53%) including two complete and 34 partial responses. 12.7% patients had progressive disease on NACT. Median PFS was 15 months (95% CI 11.6-18.4) and median OS was 22 months (95% CI 15.6-28.3) at a median follow-up of 16 months. There was a significant improvement in the OS of patients undergoing definitive therapy versus no definitive therapy (median OS 25 months [95% CI 19.4-30.3] vs 12 months [95% CI 3.2-20.3] respectively; p = 0.047, HR 1.6). Amongst patients who could not undergo definitive CTRT upfront due to dosimetric constraints (n = 36), 26 (72.2%) patients finally underwent CTRT after NACT. Those patients who were not able to undergo definitive CTRT had median PFS of 5 months [95% CI 2.1-7.9] versus 10 months [95% CI 3.8-16.1] in those who were made amenable to definitive CTRT post NACT; p = 0.018.
Pemetrexed-platinum based NACT appears to be an effective option and many borderline cases where upfront definitive therapy is not feasible may become amenable to the same after incorporation of NACT.
Clinical trial identification
Clinical Trials Registry India (registration number: CTRI/2013/01/003335)
Legal entity responsible for the study
Tata Memorial Hospital, Mumbai
All authors have declared no conflicts of interest.