Evolution of Missing Colorectal Liver Metastases Following Inductive Chemotherapy and Hepatectomy

Background: A dramatic response to chemotherapy in some patients with multiple bilateral and initially unresectable liver metastases (LM) from colorectal cancer sometimes leads to their disappearance from imaging studies. Our study was aimed at assessing the evolution of these metastases when they were also not found during liver surgery. Patients: Among 104 hepatectomized patients for colorectal LM in 4 years, 15 patients were retrospectively eligible. Eligibility criteria were: initially unresectable LM; a dramatic response to chemotherapy; and the complete disappearance of at least one LM on imaging studies (ultrasonography (US), computed tomography, and magnetic resonance) during more than 3 months. In four patients (27%), the disappeared LM could be found and treated at laparotomy. The main selection criterion for the 11 studied patients of this series was the impossibility of finding and treating the disappeared LM sited in the remaining liver after hepatectomy, resulting in "missing LM." Results: After a median follow-up of 31 months (range: 18-55) for the series, eight patients among the eleven (73%) did not present any recurrence of the missing LM. The median follow-up was 31.3 months for these eight patients. The three recurrences occurred respectively at 5, 5, and 8 months after surgery. Conclusions: The disappearance of LM after chemotherapy on high-quality imaging studies and after intra-operative liver exploration resulted in their definitive cure in approximately 70% of cases. The current dogma stipulating an obligatory resection of the initially affected part of the liver is no longer acceptable.