Pulmonary Sarcomatoid Carcinoma: Experience From SEER Database and Shanghai Pulmonary Hospital

Abstract

Background: Pulmonary sarcomatoid carcinoma (PSC) is a rare type of lung cancer. This study aimed to explore the appropriate treatment for PSC.

Methods: Two cohorts were used: patients from the Surveillance, Epidemiology, and End Results (SEER) database (1988 to 2014) and Shanghai resident patients at Shanghai Pulmonary Hospital (2009 to 2019) in China. Cox regression analysis was applied to identify prognostic factors for progression-free survival and overall survival (OS). Interaction assessments were performed using likelihood ratio tests to examine relationships between adjuvant chemotherapy and other baseline characteristics.

Results: In the SEER cohort, 1640 patients with PSC were identified, with a median survival and a 5-year OS rate of 7 months (95% confidence interval (CI), 6 to 8 months) and 19.5%, respectively. Multivariable Cox analysis of surgically treated patients revealed that adjuvant chemotherapy was significantly associated with better survival (hazard ratio, 0.78; 95% CI, 0.62 to 0.98), and the benefit was more pronounced in T3 to T4 stage (P = .04) and N-positive patients (P < .01). In the Shanghai Pulmonary Hospital cohort (n = 175), the median progression-free survival and OS were 8 months (95% CI, 7 to 12 months) and 12 months (95% CI, 10 to 18 months), respectively, with a 5-year OS rate of 25.1%. Similarly, the survival benefit of adjuvant chemotherapy was confirmed in patients with surgical resection (hazard ratio, 0.50; 95% CI, 0.31 to 0.81), but this benefit was restricted to patients who were younger (age <63 years; P = .02) and had a higher body mass index (>25 kg/m²; P < .01) by interaction assessments. The disease control rate after chemotherapy was 58.62%, and the disease control rate after targeted therapy was 57.14%.

Conclusions: Adjuvant chemotherapy should be recommended for patients with surgically treated PSC, especially for patients with advanced-stage cancer, younger age, or higher body mass index.