NMS. Casos Clínicos

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Chapter 8 ♦ Lower Gastrointestinal Disorders

Figure 8-25: Segmental colonic resections. A: Right colectomy. B: Extended right colectomy to transverse colon. C: Transversectomy. D: Right colectomy extended to splenic flexure. E: Left colectomy. F: Sigmoidectomy. (From Mulholland MW. Greenfield’s Surgery , 6th ed. Wolters Kluwer Health; 2016, Fig. 68-10.)

Q: How would you stage this colon cancer? A: Staging of colon cancer, which is performed after surgical resection, is based on depth of invasion of the primary lesion, presence of regional lymph nodes, and distant metastasis . Two methods of staging are commonly used: the tumor-node-metastasis (TNM) sys- tem and the Dukes Astler-Collier classification. The TNM system is preferred (Table 8-4). Dukes classification is historically relevant but not commonly used clinically. This tumor is a T3, N0, M0 and represents stage II or Dukes B classification. Q: Is additional therapy such as radiation or chemotherapy warranted? A: Surgery is the only treatment for most stage II cancers. High-risk stage II cancers can bene- fit from adjuvant chemotherapy. The therapy is termed “adjuvant” because it is given post- operatively to patients with no apparent residual disease. Research has found that radiation therapy plays no role. However, the prognosis in stage II cancers is worse for high-grade tumors, tumors presenting with bowel perforation, tumors with venous or perineural inva- sion, and tumors in or near the margin. Thus, some physicians would treat these patients with adjuvant chemotherapy. SAMPLE