Colorectal cancer is treated primarily by surgery. The goal of surgery is to completely remove the tumor. Surgery for carcinoma of the colon is aimed at removing the tumors with an adequate margin by a wide excision of the tumor-bearing area and
associated lymphatics, with attention to the blood supply to the segment and creation of anastomosis without tension. Both rectal and colon cancers are resected for the purpose of cure and prevention of spread and local or pelvic recurrence. The
operations generally employed for cancers above the rectum include right colectomy, transverse colectomy, left colectomy, anterior resection, subtotal colectomy, and total colectomy.
More limited resections are occasionally performed for palliation in patients with distant metastasis. The survival benefits from the no-touch technique and radical lymphadenectomy with high ligation are still controversial.
In rectal cancer, 2 ㎝ is sufficient for the distal resection margin. Several reports have demonstrated improvement in local recurrence rates and cancer-specific survival rate through TME (total mesorectal excision). The technique of
chemosensitized
irradiation was successful in down staging the tumors and in reducing the tumor size. Preoperative chemoradiation therapy and coloanal anastomosis enables the sphincter-preserving operation more frequently. The rectum, genitourinary structures,
and
the
pelvic autonomic nervous system are very closely related. The urinary and sexual function can be preserved by nerve-sparing operation for rectal cancer. The anorectal function might be improved by colonic pouch operation. Transanal excision or
trananal
endoscopic microsurgery are advocated for the definitive treatment of small, exophytic, well differentiated, mobile lesions. Resection of hepatic or pulmonary metastasis in cases with-out contraindications improves the survival.
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