Effect of histological subtype on the efficacy of perioperative chemotherapy in pulmonary sarcomatoid carcinoma: a retrospective study based on SEER population.

BACKGROUND

The efficacy of perioperative chemotherapy (PC) in pulmonary sarcomatoid carcinoma (PSC) is controversial. We conducted this study to investigate the effect of different histological subtypes on the efficacy of PC in PSC patients.

METHODS

Clinicopathological data of 811 PSC patients of different histological subtypes were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier method and log-rank test were used to evaluate the effects of PC on the overall survival (OS) and cancer-specific survival (CSS) in different subtypes of PSC patients. Propensity score matching (PSM) was used to reduce potential confounding effects. Subgroup analyses were conducted to further investigate the efficacy of PC in patients with different characteristics.

RESULTS

A total of 210 (25.89%) enrolled PSC patients received PC. PC was not associated with OS or CSS benefit in pleomorphic carcinoma, giant cell carcinoma, or spindle cell carcinoma patients, neither before nor after matching. But survival benefit of PC was observed in carcinosarcoma patients both before (5-year OS: 48.79% 38.75%, P=0.01) and after (5-year OS: 51.29% 17.54%, P=0.003) matching. Subgroup analyses showed that in patients whose tumor larger than 4 cm, PC was still associated with improved survival in carcinosarcoma, but not in the other histological subtypes of PSC.

CONCLUSIONS

The efficacy of PC varies between different subtypes of PSC. Survival benefit of PC was only observed in carcinosarcoma patients, but not in pleomorphic carcinoma, giant cell carcinoma, or spindle cell carcinoma patients. Histological subtype should be considered when treating PSC patients with PC.