Actual 10-year survival after hepatic resection of colorectal liver metastases: what factors preclude cure?

Abstract

Background: Hepatic resection of colorectal liver metastases is associated with long-term survival. This study analyzes actual 10-year survivors after resection of colorectal liver metastases, reports the observed rate of cure, and identifies factors that preclude cure.

Methods: A single-institution, prospectively maintained database was queried for all initial resections for colorectal liver metastases for the years 1992-2004. Observed cure was defined as actual 10-year survival with either no recurrence or resected recurrence with at least 3 years of disease-free follow-up. Clinical risk score was dichotomized into low (0-2) and high (3-5). Semiparametric proportional hazards mixture cure model was utilized to estimate probability of cure.

Results: We included 1,211 patients with a median follow-up for survivors of 11 years. Median disease-specific survival was 4.9 years (95% CI: 4.4-5.3). 295 patients (24.4%) were actual 10-year survivors. The observed cure rate was 20.6% (n = 250). Among 250 cured patients, 192 (76.8%) had no recurrence and 58 (23.2%) had a resected recurrence with at least 3 years of disease-free follow-up. Extrahepatic disease (n = 88), carcinoembryonic antigen >200 ng/mL (n = 119), positive margin (n = 109), and >10 tumors (n = 31) had observed cure rates less than 10%. In cure model analysis, patients with both extrahepatic disease and high clinical risk score (n = 31) had an estimated probability of cure of 3.5%.

Conclusion: Actual 10-year survival after resection of colorectal liver metastases is 24% with an observed 20% cure rate. Patients with both high clinical risk score and extrahepatic disease have an estimated probability of cure less than 5%. When such factors are identified, strong consideration may be given to preoperative strategies, such as neoadjuvant chemotherapy, to help select patients for surgical therapy.

Figure 1.

Flowchart representing current status and observed cure in study population

Figure 2

a. Kaplan-Meier plot of DSS for 1211 patients undergoing resection of CRLM from 1992–2004, 95% confidence interval represented by dotted lines. b. Kaplan-Meier DSS curve stratified by clinical risk score (CRS, 0–2 vs 3–5). Low CRS (0–2) had a 10-year DSS of 42% (95% CI: 37–46%) compared to 25% (95% CI: 21–29%) for those with a high CRS (3–5) (p < 0.001).