Synchronous colorectal liver metastases: is it time to reconsider traditional paradigms of management?

BACKGROUND

Patients with synchronous colorectal liver metastases (CLM) are typically treated with initial colorectal resection followed by arbitrary and prolonged courses of chemotherapy. Partial hepatectomy is considered only for patients without interval disease progression. This review describes the rationale for this treatment approach and the recent developments suggesting that this management paradigm should be reconsidered.

RESULTS

Because asymptomatic colorectal cancer often does not lead to complications, and given the potential benefit of chemotherapy in downsizing unresectable to resectable liver disease, most patients with asymptomatic primary tumors and unresectable synchronous CLM should be first treated with chemotherapy. In contrast, initial hepatic resection should be considered for resectable synchronous CLM. Survival benefits from prehepatectomy chemotherapy have not been established. Several reports demonstrate morbidity after hepatic resection from extended durations of irinotecan- and/or oxaliplatin-based prehepatectomy chemotherapy. Although shorter treatment periods may not have these deleterious effects on subsequent hepatic resection, prospective studies reveal that most patients with supposedly aggressive disease with short treatment durations will not be identified. Moreover, a complete radiologic response to prehepatectomy chemotherapy is not only rare but also does not equate with a complete pathological response. Finally, several studies suggest that simultaneous colorectal and minor hepatic resections can performed safely with benefits in total morbidity when compared with traditional staged procedures.

CONCLUSIONS

The traditional treatment paradigm centering on the utility of prehepatectomy chemotherapy for resectable synchronous CLM should be reconsidered. Recent developments underscore the need for prospective randomized controlled trials evaluating the optimal timing of hepatectomy relative to chemotherapy.

The role of targeted therapy in the treatment of advanced colorectal cancer

The introduction of targeted therapies in the treatment of metastatic colorectal cancer (MCRC) has resulted in significant improvements in efficacy outcomes. Both vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) inhibitors have proven to be valid and valuable agents in the management of MCRC. This review will focus on the role of the anti-VEGF monoclonal antibody, bevacizumab, and the anti-EGFR monoclonal antibodies, cetuximab and panitumumab, in MCRC. Special focus will be placed on clinical evidence supporting the use of these agents in various lines of treatment, and on KRAS as a marker of response in relationship to anti-EGFR inhibitors.