Stereotactic body radiation therapy-based treatment model for stage I medically inoperable small cell lung cancer.

PURPOSE

To report on medically inoperable stage I small cell lung cancer (SCLC) patients for whom stereotactic body radiation therapy (SBRT) was employed to manage the primary tumor.

METHODS AND MATERIALS

Review of our institutional review board approved SBRT registry revealed 6 cases of stage I SCLC out of 430 patients over a 6-year interval (2004-2010). All patients had biopsy proven disease and deemed medically inoperable by a thoracic surgeon. Our institutional approach was to treat with a combination of SBRT, platinum-etoposide chemotherapy (CHT) and prophylactic cranial irradiation (PCI). SBRT was delivered using a Novalis/BrainLAB platform and ExacTrac (BrainLab, Westchester, IL) for image guidance.

RESULTS

Patient characteristics included a median Karnofsky performance scale of 80, a median age of 68 years, 4 females, and 1 patient still smoking at presentation. Impaired pulmonary function caused inoperability in 50% of cases. Tumor characteristics included median tumor size of 2.6 cm and median positron emission tomography-standard uptake valuemax of 9. The SBRT was 60 Gy/3 fractions (3 patients), 50 Gy/5 fractions (2 patients), 30 Gy/1 fraction (1 patient). Median follow-up was 11.9 months. There was no grade 3 or higher, and 1 grade 2, toxicity. Three patients were alive at analysis and 3 patients had died of non-cancer causes. At 1 year, local control was 100%, there was no regional nodal failure, and 1 patient had distant failure (liver). Overall and disease-free survivals at 1 year were 63% and 75%, respectively.

CONCLUSIONS

Employing SBRT for stage I medically inoperable SCLC is rational, with excellent local control and encouraging disease-specific survival. The absence of regional nodal failure supports positron emission tomography for mediastinal staging. Platinum-based CHT may be feasible in vulnerable populations.