Incidence and survival in late liver metastases of colorectal cancer

Background and aims: Data concerning the risk of long-term liver metastasis following surgery of colorectal cancer in the general population are scarce. The 10-year incidence and prognosis of metachronous liver metastases remain unknown.

Methods: Among 4584 patients resected for cure for colorectal cancer recorded in two French digestive population-based cancer registries between 1985 and 2000, 602 presented metastases including liver metastases.

Results: The cumulated incidence of liver metastasis was 15% at 5 years and 17% at 10 years, and was mainly related to stage at diagnosis. The 10-year cumulative incidence was 6% for stage I and 30% for stage III. The hazard ratio was 3.2 [2.4-4.3] for stage II and 6.9 [5.1-9.2] for stage III compared with stage I. Among survivors with no recurrence five years after diagnosis, 2.2% developed liver metastasis between 5 and 10 years. Resection for cure of liver metastases was performed in 35% of patients aged under 75 years and in 10% of patients over 75 (P < 0.001). After resection for cure, 10-year relative survival improved from 21% during the period 1985-1997 to 34% during the period 1998-2011 (P = 0.023). Survival in patients with liver metastasis diagnosed between six and 12 months after surgery was less than half that in patients with metastasis diagnosed later (HR: 0.6 [0.4-1.0]).

Conclusion: Liver metastases from colorectal cancer remain a substantial problem and continue to occur long after five years. This study furnishes unbiased figures that can be used as a reference. Liver metastases that appear late have a better prognosis.