Early-Stage Primary Lung Neuroendocrine Tumors Treated with Stereotactic Body Radiotherapy: A Multi-Institution Experience
Menée à partir de données multicentriques portant sur 46 patients présentant des tumeurs neuroendocrines pulmonaires de stade précoce, cette étude analyse l'efficacité, du point de vue du contrôle locorégional, et la toxicité d'une radiochirurgie
Purpose: Current guidelines recommend surgery as standard of care for primary lung neuroendocrine tumor (LNET). Given that LNET is a rare clinical entity, there is a lack of literature regarding treatment of LNET with stereotactic body radiotherapy (SBRT). We hypothesized that SBRT could lead to effective locoregional tumor control and long-term outcomes. Methods and Materials: We retrospectively reviewed 48 tumors in 46 patients from 11 institutions with a histologically confirmed diagnosis of LNET, treated with primary radiotherapy. Data was collected for patients treated nonoperatively with primary radiotherapy between 2006-2020. Patient records were reviewed for lesion characteristics and clinical risk factors. Kaplan-Meier analysis, log-rank tests and Cox multivariate models were used to compare outcomes. Results: Median age at treatment was 71 years and mean tumor size was 2 cm. Thirty-two lesions were typical carcinoid histology, 7 were atypical, and 9 were indeterminate. The most common SBRT fractionation schedule was 50–60 Gy in 5 daily fractions. Overall survival at 3, 6, and 9 years was 64%, 43%, and 26%, respectively. Progression-free survival at 3, 6, and 9 years was 88%, 78%, and 78%, respectively. Local control at 3, 6, and 9 years was 97%, 91%, and 91%, respectively. There was one regional recurrence in a paraesophageal lymph node. No grade 3 or higher toxicity was identified. Conclusions: This is the largest series evaluating outcomes in patients with LNET treated with SBRT. This treatment is well tolerated, provides excellent locoregional control, and should be offered as an alternative to surgical resection for patients with early-stage LNET, particularly those who may not be ideal surgical candidates.
International Journal of Radiation Oncology, Biology, Physics 2023