Clinical Implications of Large Bowel Carcinoma

Abstract

Colorectal cancer is the third most common cancer in the world. In the USA, 150,000 new cases are diagnosed annually, whereas in Europe the respective incidence is 400,000. The ratio of colonic to rectal cancer is 2:1. With the incidence of rectal cancer rising. Colorectal cancer is more common in males than females. Colonoscopy with biopsy is the most often used method for diagnosis. Cross-sectional imaging follows colonoscopy for staging purposes in an effort to detect metastatic disease. CT and MRI are not recommended for detection of the colonic primary lesion, however, as always used for identification of extracolonic pelvic disease and/or metastatic lesions through the body. However, PET-CT scan is extremely useful for whole-body imaging especially in restaging where lung or liver metastasectomy is the preferred mode of treatment. Specifically for rectal cancer, staging is of major importance for treatment planning. Endorectal ultrasound (ERUS) and MRI visualize the extent of the tumor as well as the circumferential resection margin which is significant for total mesorectal excision. The ideal surveillance strategy for colorectal cancer has not been defined. NCCN guidelines recommend CT scans of upper and lower abdomen as well as chest every year for 5 years. Colonoscopy is recommended 1 year following surgery and then at 3 years and then every 5 years.

† Author was deceased