A Retrospective Long-term Follow-up Study of Stereotactic Body Radiation Therapy for Non-Small Cell Lung Cancer From a Single Institution: Incidence of Late Local Recurrence

作者:Shintani Takashi; Matsuo Yukinori; Iizuka Yusuke; Mitsuyoshi Takamasa; Mizowaki Takashi
来源:International Journal of Radiation Oncology, Biology, Physics, 2018, 100(5): 1228-1236.
DOI:10.1016/j.ijrobp.2018.01.050

摘要

Purpose: To assess the local recurrence (LR) rate and timing after stereotactic body radiation therapy (SBRT) for non-small cell lung cancer using long-term follow-up data from a single institution.
Methods and Materials: Patients with primary or recurrent non-small cell lung cancer with or without pathologic verification, with tumors <3 cm, treated with SBRT (isocenter prescription of 48 Gy in 4 fractions) between April 1998 and August 2014, and with >6 months' follow-up were eligible. The LR rate was calculated by the cumulative incidence function, accounting for death as a competing risk. Univariate and multivariate analyses were performed to identify prognostic factors for LR.
Results: A total of 216 patients and 230 tumors were analyzed. The median follow-up time of tumors without LR was 3.9 years, and the crude number of LR cases was 49 (21%). The actuarial rate of LR was 19% (95% confidence interval, 14%-25%) at 5 years. The number of LR cases in each period was 10 in year 1, 17 in year 2, 9 in year 3, 3 in year 4, 3 in year 5, and 7 after 5 years. Among 73 tumors with >5 years' follow-up, we observed 7 late LRs. The tumor histology of these late LRs was adenocarcinoma in 3, squamous cell carcinoma in 2, and unknown in 2 (1 of the unknown cases was confirmed as adenocarcinoma following salvage surgery). The median time to LR was 2.1 years (interquartile range, 1.5-4.2 years) for adenocarcinoma compared with 1.3 years (interquartile range, 1.0-2.3 years) for squamous cell carcinoma. Multivariate analysis revealed that larger tumor size, squamous cell histology compared with adenocarcinoma, and use of abdominal compression for respiratory motion management were independent negative prognostic factors for LR.
Conclusions: Long-term follow-up data demonstrated that late LR was not uncommon and that careful follow-up after SBRT is needed, especially in patients with adenocarcinoma.

  • 出版日期2018-4-1