Thoracic radiotherapy timing and prognostic factors in elderly patients with limited-stage small cell lung cancer

Precis Radiat Oncol. 2024 Mar 14;8(1):14-21. doi: 10.1002/pro6.1223. eCollection 2024 Mar.

Abstract

Objective: This study assessed the outcomes of elderly patients with limited-stage small cell lung cancer (LS-SCLC), which may be linked to the timing of thoracic radiotherapy (TRT) following chemotherapy.

Methods: Elderly patients (n = 78) with LS-SCLC were divided into three groups depending on the timing of radiotherapy. The patients in the TRT group were stratified into early (TRT after 1-2 cycles of chemotherapy, n = 29), medium-term (TRT after 3-4 cycles of chemotherapy, n = 33), and late (TRT after 5-6 cycles of chemotherapy, n = 16) TRT groups. The overall survival (OS) and progression-free survival (PFS) were assessed and compared.

Results: The medium-term TRT group demonstrated significantly longer mPFS (20.12 months) and better mOS (35.97 months) than those in the other groups (PFS: P = 0.021;OS: P = 0.035). A pairwise comparison of the three groups revealed that those who received medium-term TRT exhibited significantly improved PFS than the early (mPFS: 20.12 vs. 10.36 mouths, P = 0.018) and late (mPFS: 20.12 vs. 9.17 months, P = 0.016) TRT. The medium-term TRT group demonstrated significantly improved OS than the early TRT (mOS: 35.97 vs. 25.22 months, P = 0.007) but not in comparison with the late TRT (mOS: 35.97 vs. 21.63 months, P = 0.100).

Conclusion: In elderly patients with LS-SCLC, the addition of TRT after 3-4 cycles of chemotherapy appears to be a viable and potentially beneficial treatment approach.

Keywords: elderly patients; intensity modulated radiation therapy; limited‐stage small cell lung cancer; prognosis; radiotherapy timing; thoracic radiotherapy.