Diagnostic Efficacy of CXR Compared to Chest CT in Preoperative Staging of Patients with Colorectal Cancer

The high prevalence of colorectal cancer (CRC) and its increasing incidence can be a major problem in cancer management. Preoperative staging plays a significant role in the therapeutic process, especially in CRC which has high risk for lung metastases. This study aimed to evaluate accuracy of chest X-ray (CXR) in comparison with chest CT (CCT) for diagnosing lung metastases in patients with CRC.
Patients and A cross sectional study was conducted of 377 patients with newly diagnosed CRC which were evaluated with CXR and CCT. CCT revealed normal/benign findings in 285 (75.6%), indeterminate nodules in 28 (17%) and suspicious nodules in 64 (17%) patients. Although CXR did not reveal any pulmonary metastatic lesions in of the 23 (7%) patients, the measure of agreement between CXR and CCT was good (0.64, P < 0.01) and CCT changed TNM staging in only eight (2%) patients. On logistic regression analysis, liver metastasis could increase the risk of pulmonary metastasis (P < 0.01). The study suggested CCT for preoperative staging in CRC patients, especially at stages 3 and 4 in TNM staging and for liver metastases.