Optimal use of current chemotherapy in multimodality therapy for advanced colorectal cancer.

Treatment of advanced colorectal cancer (CRC) increasingly requires a multimodality approach, which adds to the complexity of clinical decision-making. This study investigates the optimal use of current chemotherapy in multimodality therapy for advanced CRC. We enrolled 208 patients with unresectable primary and metastatic (recurrent) CRC who underwent chemotherapy in our hospital. Radiofrequency ablation and/or secondary surgery were used depending on tumor response to chemotherapy. Disease sites varied among patients and included unresectable liver, lung and peritoneal metastasis. Chemotherapy produced cytoreduction in 71 of 208 patients (34%). Multimodality cytoreduction increased overall survival to a median of 46.0 months vs. 20.2 months with chemotherapy alone (P<0.0001). The response rate to chemotherapy was independently associated with cytoreduction. Molecular targeted therapy reduced the number of tumor cells sooner than conventional chemotherapy, and correlated with repeated cytoreduction that further prolonged survival. Aggressive chemotherapy as initial treatment for advanced CRC leads to cytoreduction and is associated with extended survival in patients receiving multimodality therapy.