Shintaro Hashimoto, Tetsuro Tominaga, Toshio Shiraishi, Keisuke Noda, Mariko Yamashita, Hiroki Katayama, Yuma Takamura, Satoshi Mizoguchi, Tomohiro Obata, Daisuke Taniguchi, Ryoichiro Doi, Koichiro Shimoyama, Takuro Miyazaki, Makoto Hisanaga, Mitsutoshi Ishii, Rika Ono, Takaaki Nakatsukasa, Ryoichiro Kamohara, Masato Araki, Yorihisa Sumida, Akihiro Nakamura, Takashi Nonaka, Keitaro Matsumoto
In this dual-center retrospective cohort, postoperative adjuvant chemotherapy was associated with improved overall survival after resection for large-cell neuroendocrine carcinoma, whereas no significant association was observed for disease-free survival. The overall survival association appeared stronger in selected higher-risk subgroups, including patients with stage II-III disease and node-positive disease. Further studies are warranted to better define the patients most likely to benefit from adjuvant chemotherapy.
BACKGROUND: Although pulmonary metastasectomy is an established treatment for colorectal cancer, recurrence is frequent. Repeat resection for hepatic recurrence is a recognized paradigm, but the clinical significance of salvage surgery for pulmonary recurrence remains less defined. This study evaluated recurrence patterns and the association with salvage R0 resection on post-recurrence survival using a time-dependent model.
METHODS: We retrospectively reviewed 182 patients who achieved R0 resection at their initial pulmonary metastasectomy at two institutions between 2008 and 2022. Post-recurrence survival was calculated from the date of first recurrence. To account for immortal time bias, salvage R0 resection was modeled as a time-dependent covariate in a multivariable Cox model.
RESULTS: Recurrence occurred in 76 patients (41.8%). Single-organ recurrence was observed in 80.3%, with the lung being the most frequent site (42.6%) among single-organ recurrences. Salvage R0 resection was achieved in 33 patients (43.4%), all of whom had single-organ recurrence. The 5-year post-recurrence survival was significantly higher in the salvage R0 group than in the non-R0 management group (53.0% vs. 14.6%; log-rank p < 0.001). In the time-dependent multivariable analysis, achieving salvage R0 resection was independently associated with improved post-recurrence survival (hazard ratio 0.359; 95% confidence interval 0.163-0.794; p = 0.011). Six patients remained recurrence-free for over 5 years after salvage R0 resection without systemic therapy.
CONCLUSIONS: Achieving salvage R0 resection provides a significant survival benefit comparable to repeat hepatectomy outcomes. For patients with single-organ recurrence after pulmonary metastasectomy, aggressive local intervention aimed at R0 resection should be considered a key therapeutic strategy.