48P - Long-term clinical outcomes after the second metastasectomy in patients (pts) with resected metastatic colorectal cancer (mCRC)

Background

Primary tumor resection and metastasectomy are curative options in some pts with mCRC. However, there is still a paucity of data regarding clinical outcomes and risk factors after disease recurrence and second metastasectomy in these pts.

Methods

We retrospectively evaluated the clinical outcomes of pts with mCRC undergoing a second metastasectomy at Seoul National University Bundang Hospital. In addition, the risk factors for the outcomes were analyzed.

Results

Among 269 pts who had achieved a disease-free state after primary tumor resection and first metastasectomy, 94 pts (female, 39 pts) received a second metastasectomy after recurrence, between Jul. 2006 and Feb. 2019. The median age was 62 years (range, 34-78 years). The primary tumor location was right colon in 16 pts (17.0%), left colon in 46 pts (48.9%), and rectum in 32 pts (34.0%). Recurred sites were lung in 47 pts (50.0%), liver in 36 pts (38.3%), both lung and liver in 4 pts (4.3%), and non-lung/non-liver in 7 pts (7.4%). Among them, 89 pts (94.7%) achieved R0 resection, while 3 (3.2%) and 2 (2.1%) pts underwent R1/R2 resection, respectively. During a median follow-up of 86.6 months (range, 39.5-193.0 months), the 5-year OS was 67.2±4.9%. Multivariate analysis for OS showed that age ≥70 years (HR 3.27 [95% CI, 1.31-8.15], P=0.011), non-lung/non-liver metastasis (HR 4.04 [95% CI, 1.21-13.51], P=0.024) and lesion number ≥2 (HR 2.25 [95% CI, 1.12-4.54], P=0.023) were poor prognostic factors. Among R0 resected pts, the 5-year DFS was 42.8±5.3%. Multivariable analysis for DFS identified that primary rectal cancer (HR 0.45 [95% CI, 0.22-0.94], P=0.033) and disease-free interval (DFI) after first metastasectomy ≥12 months (HR 0.39 [95% CI, 0.21-0.71], P=0.002) were good predictive factors while non-lung/non-liver metastasis (HR 3.32 [95% CI, 1.21-9.11], P=0.020) was a poor predictive factor.

Conclusions

Pts who received the second metastasectomy had a long-term disease-free state and good OS. Our data suggest that the second metastasectomy should be considered if a pt has liver- and/or lung-limited metastasis of limited number and long DFI after the first metastasectomy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.