Purpose: Resection of liver-only colorectal liver metastases (CRLM) with perioperative chemotherapy is potentially curative. Specific primary tumor and liver metastasis characteristics have been validated to estimate the risk of recurrence. We hypothesize that the time interval from diagnosis of CRLM to surgery, or time to surgery (TTS), is clinically prognostic.
Methods: Patients from a prospectively maintained institutional database at a Comprehensive Cancer Center from May 2003 to January 2018 were reviewed. Clinicopathologic, perioperative treatment, and TTS data were collected. TTS was categorized into short (< 3 months), intermediate (3-6 months), and long (> 6 months) intervals.
Results: Two hundred eighty-one patients were identified. While overall survival (OS) was similar across TTS, postoperative overall survival (postoperative OS) of long TTS was associated with worse survival, 44 months (95% CI, 34-52) compared to short TTS, 59 months (95% CI, 43-79), and intermediate TTS, 63 months (95% CI, 52-108), both p < 0.01. With regard to long-term OS, intermediate TTS had 5-year OS of 59% and 8-year OS of 43% compared to long TTS (5-year OS 53% and 8-year OS 18%) and short TTS (5-year OS 54% and 8-year OS 29%). Long TTS was negatively associated with postoperative OS on multivariate analysis (HR 1.6, p < 0.01) when adjusting for resection margin, CRLM size, age, and use of postoperative chemotherapy.
Conclusion: Short and intermediate TTS had similar survival although patients with intermediate TTS may have better odds of long-term OS. While long TTS was associated with worse survival, likely due to higher disease burden, long-term survivors were still observed.
Keywords: Chemotherapy; Clinical risk score; Colorectal cancer; Colorectal liver metastases; Time to surgery.