Should preoperative chest CT be recommended to all colon cancer patients?

OBJECTIVE: The aim of this study was to evaluate the efficacy of preoperative chest computed tomography (CT) and the risk factors for lung metastasis in colon cancer patients without liver metastasis who had negative findings on initial chest X-ray (CXR). BACKGROUND: Preoperative staging with chest CT is recommended in colon cancer patients. However, there have been only scant data on the clinical efficacy. METHODS: Three hundred nineteen consecutive colon cancer patients without liver metastasis were retrospectively reviewed and analyzed. The patients had negative findings on preoperative CXR, and they underwent surgery for colon cancer during the period of January 2008 to April 2010. RESULTS: Lung nodule on chest CT was found in 136 patients (42.6%). Twenty of those were definitely diagnosed with lung metastasis (6.3%) by follow-up chest CT or pathologic confirmation. There was no case of delay in surgery due to findings of lung nodule. Comparing the group with lung metastases to that without lung metastases, postoperative pathologic findings reported more advanced T and N status (P = 0.004, P < 0.001, respectively), and lymphatic invasion was more frequent (P = 0.003) in the group with lung metastasis. By multivariate analysis, CT-predicted lymph node metastases and pathologic lymph node metastases were risk factors for lung metastases. CONCLUSIONS: Preoperative staging chest CT is not beneficial to colon cancer patients without liver metastasis and lymph node metastasis suggested on abdominal and pelvic CT who had negative finding on initial CXR.