Association between tumor cell in air space and treatment outcomes in early-stage lung cancer treated with stereotactic body radiation therapy.

Background and Purpose: Spread-through air space (STAS) is an unfavorable factor in patients with lung cancer treated with surgery. However, the relationship between the treatment outcomes of stereotactic body radiation therapy (SBRT) for lung cancer and STAS has not been adequately investigated. This study aimed to evaluate the impact of tumor cells in the air space (TCIAS), which show a STAS burden, on treatment outcomes in patients with early-stage lung cancer treated with SBRT.
Materials and Methods: Data of patients who underwent SBRT for early-stage lung cancer treated with SBRT were retrospectively reviewed. The influence of the TCIAS status on local progression-free (LPF), regional failure-free (RFF), distant failure-free (DFF), progression-free survival (PFS), and overall survival (OS) rates was assessed using univariate and multivariate analyses.
Results: Overall, 68 patients were included. The median follow-up time was 24.3 months. For patients positive/negative for TCIAS, the 2-year LPF, RFF, DFF, PFS, and OS rates were 81.4 %/91.1 %, 73.7 %/96.2 %, 55.9 %/75.3 %, 55.0 %/84.6 %, and 67.8 %/92.2 %, respectively. In the multivariate analysis, TCIAS-positive was a significant unfavorable factor for RFF (hazard ratio [HR]: 4.10; 95 % confidence interval [CI]: 1.04-16.16, p = 0.04), DFF (HR: 2.61, 95 % CI: 1.03-6.57, p = 0.04), and PFS (HR: 2.36; 95 % CI: 1.05-5.30, p = 0.04). By contrast, TCIAS-positive was not a significant risk factor for LPF and OS.
Conclusion: TCIAS-positive is an unfavorable factor for regional and distant failure after SBRT. TCIAS status may be useful in predicting the treatment outcome of SBRT for early-stage lung cancer.
Competing Interests: Toshiyuki Kozuki received honorarium from MSD, Ono, Kyowa Hakko Kirin, AstraZeneca, Boehringer Ingelheim, Chugai, TAIHO, Eli Lilly, Bristol Myers Squibb, Pfizer, Merck Biopharma, Nippon Kayaku, Novartis, Bayer, Sawai and AMGEN, consulting fee from Chugai, AstraZeneca, Ono, Pfizer, Daiichi-Sankyo, Bayer, and Abbvie, and received research funding MSD, Kyowa Hakko Kirin, AstraZeneca, Eli Lilly, Pfizer, Chugai, TAIHO, Ono, Bristol-Myers, Merck Biopharma, Daiichi-Sankyo, AbbVie, AMGEN, Sanofi, Eisai, Labcorp Development, IQVIA Services, Gilead Sciences, Pfizer, and Bayer. All other authors declare that they have no conflict of interest.
(© 2024 The Author(s).)