Stereotactic body radiotherapy (SBRT) is widely used as a curative treatment option for stage I non-small-cell lung cancer, but for patients with stage I small-cell lung cancer, the role of stereotactic body radiotherapy is unclear. In this study, we retrospectively analyzed the outcomes of a subset of patients with stage I small-cell lung cancer treated with stereotactic body radiotherapy in the database of the Japanese Radiological Society-Multi-Institutional stereotactic body radiotherapy Study Group. The 43 patients treated with stereotactic body radiotherapy for stage I small-cell lung cancer between 2004 and 2012 at 11 Japanese institutions were studied: median age = 77 years; 32 (74%) males and 11 females; and 80% were medically inoperable. The clinical stage was IA in 31 and IB in 12. In all patients, the lung tumors were pathologically proven as small-cell lung cancer. A total dose of 48 to 60 Gy was administered in 4 to 8 fractions. The median biologically effective dose (α/β = 10 Gy) was 105.6 Gy. Chemotherapy and prophylactic cranial irradiation were administered in only 8 patients, respectively. The median follow-up time was 23.2 months. The 2-year overall survival, progression-free survival, and distant metastasis-free survival rates were 72.3%, 44.6%, and 47.2%, respectively. The 2-year local control was 80.2%. Regarding the patterns of failure, distant metastasis, lymph node metastasis, and local recurrence were observed in 47%, 28%, and 16% of patients, respectively. No ≥grade 3 stereotactic body radiotherapy-related toxicities were observed. Although stereotactic body radiotherapy was thus revealed to be effective for the local control of stage I small-cell lung cancer, the incidence of distant metastases was high. Further investigations of larger cohorts are needed, including analyses of the effects of combined chemotherapy.
All Science Journal Classification (ASJC) codes
- Cancer Research