Predictors and outcome of complete removal of colorectal cancer with synchronous lung metastases.

The prognosis-improving effect of radical surgery has been demonstrated in patients with colorectal cancer (CRC) with liver metastases. However, few studies have examined the effectiveness of treatments for CRC with metastases in organs other than the liver. The aim of the present study was to evaluate the outcome of surgical treatment for CRC with lung metastases. The study retrospectively examined 57 primary CRC patients (28 men, median age of 65 years) with synchronous lung metastases who underwent surgery between 2003 and 2012. Data such as clinicopathological parameters, metastasized organs, and the details of surgery, recurrence and survival periods were extracted and analyzed. Curative resection was performed in 10 patients ('curative group'). Primary tumors were resected without metastasectomy in 37 patients ('non-curative group'), whereas 10 underwent stoma surgery ('stoma group'). All the metastasized lesions were confined to the lung and liver in the curative group. By contrast, 43% of the non-curative/stoma groups had metastases in organs other than the lung and liver. Multivariate analyses indicated the absence of extrahepatic metastases as the only predictor of curative resection in CRC patients with lung metastases. The 3-year overall survival rates for the curative, non-curative and stoma groups were estimated as 74, 20 and 17%, respectively (P=0.0007). In conclusion, curative resection was possible in CRC patients with lung metastases if other disseminated lesions were limited to the liver and this treatment resulted in a longer survival time. Furthermore, palliative resection may contribute to a better prognosis compared to stoma surgery alone in selected cases.