Effect of sequential chemoradiotherapy in patients with limited-disease small-cell lung cancer who were ineligible for concurrent therapy: a retrospective study at two institutions

Background: The standard treatment for limited-disease small-cell lung cancer (LD-SCLC) is a combination of chemotherapy and concurrent thoracic radiotherapy. In selected cases, sequential radiotherapy is preferred because of the need for a large irradiation field, patient age, comorbidities or performance status. Nevertheless, the efficacy of sequential chemoradiotherapy in patients in whom concurrent chemoradiotherapy is contraindicated is not well known.

Methods: We retrospectively analyzed 286 patients with LD-SCLC at two institutions in Japan between 2000 and 2014. We compared the clinical characteristics and treatment outcomes of patients undergoing sequential radiotherapy with those undergoing concurrent radiotherapy.

Results: One hundred and seventy-five patients received concurrent chemoradiotherapy, 33 received sequential chemoradiotherapy and 46 received chemotherapy only. The median patient age was 64 years (range, 18-82 years) for the concurrent group and 71 years (49-82 years) for the sequential group. Conventional radiotherapy was selected more frequently than accelerated hyperfractionated radiotherapy (27 patients [82%] with conventional radiotherapy, and six patients [18%] with hyperfractionated radiotherapy). The major reasons for the selection of sequential radiotherapy were advanced age (12 patients) and a large irradiation field (11 patients). The median overall survival time was 41.1 months for the sequential group and 38.1 months for the concurrent group. The 5-year survival rates were 36.0% for the sequential group and 41.6% for the concurrent group.

Conclusions: In clinical situation, since the treatment outcomes for patients with sequential radiotherapy were comparable to those receiving concurrent radiotherapy, sequential chemoradiotherapy can be a choice for the treatment of patients who are not candidates for concurrent chemoradiotherapy.