Comparison of clinical prognosis of chemo-radiotherapy and surgical treatment for patients with limited stage small cell lung cancer after matching

Abstract

Objective To compare the overall survival (OS), progression-free survival (PFS) and brain metastasis free survival (BMFS) between the chemo-radiotherapy and surgical treatment for patients with limited stage small cell lung cancer (LS-SCLC). Methods Clinical data of 69 patients diagnosed with LS-SCLC undergoing surgery in Zhejiang Cancer Hospital between 2000 and 2016 were collected. According to T, N stage, treatment duration, age, gender and whether or not prophylactic cranial irradiation (PCI), 69 patients of 503 LS-SCLC patients who underwent standard radiochemotherapy were assigned into the radiochemotherapy group by using the pair-matched case-control method. Results Among 138 patients, 69 cases were allocated into the surgery group (24 cases of stage Ⅰ, 14 cases of stage Ⅱ and 31 cases of stage Ⅲ) and 69 cases in the radiochemotherapy group (24 cases of stage Ⅰ, 14 cases of stage Ⅱ and 31 cases of stage Ⅲ). The median OS time was 37.1 months (95%CI: 24.1-50.2 months) in surgery group and 45.0 months (95%CI: 15.8-74.2 months) in the radiochemotherapy group. The 2-and 5-year OS rates were 60% and 45% in the surgery group, and 64% and 45% in the radiochemotherapy group (P=0.846). The median PFS time was 27.1 months (95%CI: 0.00-60.3 months) in the surgery group and 36.2 months (95%CI: 20.9-51.4 months) in the radiochemotherapy group. The 2-and 5-year PFS rates were 52%, and 38% in the surgery group, and 56% and 40% in the chemo-radiotherapy group (P=0.610). The 2-and 5-year BMFS rates were 81% and 76% in the surgery group, and 84% and 80% in the radiochemotherapy group (P=0.774). The 5-year OS rate (62% vs. 40%, P=0.038) and 5-year PFS rate (80% vs.40%, P=0.048) for patients with stage Ⅰ LS-SCLC in the surgery group were significantly higher than those in the radiochemotherapy group. However, the 5-year BMFS rate in patients with stage Ⅰ LS-SCLC did not significantly differ between two groups (92% vs.95%, P=0.816). The 5-year OS rate (41% vs.51%, P=0.946), 5-year PFS rate (65% vs.42%, P=0.280) and 5-year BMFS rate (75% vs.78%, P=0.720) for stage Ⅱ SCLC did not significantly differ between two groups. As for stage Ⅲ SCLC patients, the OS rate (25% vs.48%, P=0.220), 5-year PFS rate (28% vs.36%, P=0.333) and 5-year BMFS rate (76% vs. 74%, P=0.84) did not significantly differ between two groups. Conclusions Surgical treatment can bring survival benefits to patients with stage Ⅰ LS-SCLC. The survival prognosis of stage Ⅱ patients is equivalent between two groups. Patients with stage Ⅲ LS-SCLC receiving radiochemotherapy obtain better survival trend compared with those undergoing surgery. The conclusion remains to be validated by studies with larger sample size or prospective investigations. Key words: Lung neoplasm/surgery; Lung neoplasm/radiochemotherapy; Prognosis