The indication of local excision for T2 rectal carcinomas

BACKGROUND

Several researchers reported that local excision with or without postoperative chemo-radiation therapy is an alternative approach for sphincter preservation in patients with locally invasive rectal carcinoma. However, indications and long-term results have not yet been determined.

METHODS

Seventy-two patients with T2 colorectal carcinomas underwent bowel resection with regional lymph node dissection. The associations between lymph node metastasis (LNM) and clinicopathologic factors were examined with special reference to the presence or absence of moderate to severe degree of focal dedifferentiation or mucinous component at the invasive margin (unfavorable histology).

RESULTS

Multivariate logistic regression analysis revealed that both sex and unfavorable histology were significantly associated with LNM (P = 0.0102, 0.0226, respectively). However, the associations between LNM and lymphatic invasion or tumor location were not statistically significant (P = 0.0947, 0.1738).

CONCLUSIONS

When locally resected T2 rectal carcinoma specimens have unfavorable histology at the invasive margin, additional bowel resection with lymph node dissection should be recommended.

A clinicopathological investigation on superficial early invasive carcinomas of the colon and rectum

Due to recent advances in endoscopic surgical techniques, it has now become possible to perform endoscopic resection of most early invasive carcinomas of the colon and rectum (EIC) even if the lesions have invaded the submucosa. In the present study, we investigated the microscopic characteristics of superficial EIC compared with protruding-type EIC, focusing particular attention on histological type, the presence or absence of vascular invasion, the extent of submucosal invasion, and other adverse prognostic factors, to establish appropriate treatment strategies. Our findings led us to conclude that: (1) most cases of EIC can be cured by endoscopic resection if their gross aspects are classified as type IIc, superficial depressed, or type IIa, superficial elevated; (2) colorectal resection with lymph node dissection should be performed first for type IIa + IIc EIC because these lesions are apt to be associated with a large number of adverse prognostic factors; (3) subsequent colorectal resection should be performed after initial endoscopic treatment of EIC if there are adverse prognostic indicators of metastasis in the endoscopically resected specimen, such as moderately or poorly differentiated adenocarcinoma, lymphatic invasion, venous invasion, or extensive submucosal invasion.