An evaluation of neural invasion in esophageal cancer.

It is well known that the operative results for esophageal cancer, especially thoracic esophageal cancer, are not favorable. We analyzed the relationship between neural invasion (NI) and histopathologic factors and recurrence types in 104 patients who underwent resection of esophageal cancers with T2 or greater depth of invasion of the esophageal wall. The implications of NI as a prognostic indicator were also examined. Of the 104 patients, 48 (46.2%) were NI-positive (NI(+)) and 56 (53.8%) were NI-negative (NI(-)). The NI(+) patients had a higher ratio of type 3 cancer. Concerning the histopathologic factors, there was a significant relationship between NI and lymph node metastasis (N) and between NI and lymphatic vessel invasion (ly) (P < 0.05). Examining the types of recurrence, namely hematogenous, lymphogenous, and local/stump, as well as pleural or peritoneal dissemination, a relationship was observed between lymphogenous recurrence and N or ly, and between local/stump recurrence and NI. The prognosis of the NI(+) patients was significantly different from that of the NI(-) patients. According to a multivariate analysis, NI and N were significant prognostic factors. These findings demonstrate that NI is an important prognostic factor closely related to local recurrence in patients with esophageal cancer. Thus, when treating advanced esophageal cancer with T2 or greater depth of invasion, NI and lymph node excision should be considered.

Analysis of regional lymph node metastases from rectal carcinoma by the clearing method. Justification of the use of sigmoid in J-pouch construction after low anterior resection.

PURPOSE: It has been reported that functional outcome following low anterior resection of resection of rectal cancer is improved by construction of a colonic J-pouch compared with straight anastomosis. Hence, we tried to justify use of the sigmoid colon in the construction of a J-pouch by the analysis of regional lymph node metastases. METHODS: A total of 182 patients underwent resection for rectal cancer. Node metastases were examined by the clearing method. According to Japanese General Rules for Clinical and Pathological Studies on Cancer of the Colon, Rectum and Anus (JGR), nodes were classified into the perirectal nodes (PR-N), pericolic nodes (PC-N), central intermediate nodes (C-IM-N), central main nodes (C-M-N), lateral intermediate nodes (L-IM-N), and lateral main nodes (L-M-N). RESULTS: Metastatic rate (number of patients with node metastases/total number of patients) of PR-N was 57.1 percent. Metastatic rate of C-IM-N was 18.7 percent and that of C-M-N was 7.1 percent. Metastatic rates of L-IM-N and L-M-N were 8.8 and 3.3 percent, respectively, and both were highest in the case of lower rectal cancer. Metastatic rate of PC-N was only 1.1 percent. The number of cases without node metastases (n(-) cases) was 78, that with only PR-N metastases (PR-N cases) was 63, that with intermediate but not main node metastases (IM-N cases) was 29, and that with main node metastases (M-N cases) was 12. Five-year survival rate after curative resection was 88.5 percent for n(-) cases, 70.9 percent for PR-N cases, 65.9 percent for IM-N cases, and 41.7 percent for M-N cases. CONCLUSIONS: In low anterior resection, high ligation of the inferior mesenteric artery and dissection of C-M-N, C-IM-N and PR-N are necessary, with the addition of the L-IM-N and L-M-N in the case of lower rectal cancer. Resection of sigmoid colon is not required, and therefore, a J-pouch can be constructed using the sigmoid colon. Nodal classification according to the JGR was predictive of case distribution and five-year survival rate.

Functional outcome after low anterior resection with low anastomosis for rectal cancer using the colonic J-pouch. Prospective randomized study for determination of optimum pouch size.

PURPOSE: Functional outcome after low anterior resection with ultralow coloanal anastomosis for rectal cancer is improved by construction of a colonic J-pouch vs. straight anastomosis. Optimum size of this pouch has yet to be determined. Therefore, we initiated a prospective, randomized trial using 5-cm and 10-cm pouches to determine this size. METHODS: Patients with tumors 5 to 10 cm from the anal verge were included in the study. Before a low anterior resection anastomosis was performed, patients were randomized to either a 5-cm J-pouch group (5-J group) or a 10-cm J-pouch group (10-J group). Functional assessments were performed one year postoperatively. Clinical functions were evaluated using a functional scoring system. Physiologic functions, such as sphincter and reservoir function, were evaluated by anorectal manometry and evacuation function by the balloon expulsion and saline evacuation tests. RESULTS: Forty patients among 43 randomized patients were assessed for functional outcome one year postoperatively (5-J group, n = 20; 10-J group, n = 20). The functional score was similar for the two groups, although reservoir function in the 5-J group was significantly less than in the 10-J group. Sphincter function was similar between the two groups. Evacuation function in the 5-J group was significantly superior to that in the 10-J group. CONCLUSIONS: The 5-cm J-pouch conferred adequate reservoir function without compromising evacuation.

Second-look operation for recurrent colorectal cancer based on carcinoembryonic antigen and imaging techniques.

PURPOSE: The usefulness of postoperative carcinoembryonic antigen (CEA) monitoring and improvements in imaging techniques have renewed enthusiasm for second-look operations (SLO) as the most effective treatment for recurrent colorectal cancer by reresection following early detection. The aim of our study is to evaluate the role of CEA and imaging techniques-directed SLO. METHODS: Seven hundred fifty-six patients with Dukes Stages B and C, who had undergone curative resection, were monitored postoperatively using CEA and imaging techniques. An SLO was performed on any potentially resectable recurrence, and in addition, an SLO was done when a persistently rising CEA value was detected. RESULTS: Recurrence developed in 18.8 percent (142/756) of patients, and 90.8 percent (129/142) of the recurrences were detected within the first three years following curative resection. When comparing carcinomas of the colon with that of the rectum, the former were associated with significantly more hepatic and intraabdominal recurrences, whereas the latter had significantly more locoregional and pulmonary recurrences. Seventy-two patients underwent SLO. Of these patients, 54.2 percent (39/72) had all of their disease resected, and 1.4 percent (1/72) had no detectable disease at the SLO. Among the 142 patients with recurrence, 71 (50 percent) patients underwent SLO. The resectable group at SLO carried a significantly better survival than the unresectable recurrence group (41.3 vs. 5.2 percent; P<0.01). CONCLUSIONS: Complete removal of colorectal cancer recurrences by SLO, on the basis of postoperative, follow-up CEA and imaging technique findings, results in improved survival.

[Prognostic predictors in colorectal cancer].

The prognostic significance of clinicopathologic factors in colorectal cancer was evaluated in a multivariate analysis. The most important independent factor affecting survival was stage (depth of penetration through the bowel wall and the presence of positive lymph nodes). All other clinicopathologic factors were of less importance than stage in determining prognosis. Although the prognostic relevance of biologic and molecular variables has been investigated extensively, the importance of these factors as prognostic predictors remains uncertain and further studies are needed.

The role of basement membrane in colorectal cancer invasion and liver metastasis.

BACKGROUND: Basement membrane (BM) is a specialized extracellular matrix component that plays a key role in tumor invasion and metastasis. METHODS: Immunohistochemical staining for two major components of BM, type IV collagen (C IV), and laminin (LN), utilizing avidin-biotin-peroxidase complex detection to examine 182 primary colorectal cancers (pT2 or greater) and 20 liver metastases. RESULTS: The distribution of C IV was the same as of LN in colorectal cancer tissue, and in normal tissue. Both C IV and LN staining were more frequently positive in the superficial zone but infrequently in the deep zone of the primary tumor. BM preservation, C IV and LN staining in both the superficial and deep zones, was seen in 18.7% of the subjects. The rate of BM preservation significantly decreased with increasing histologic grade (P < 0.01). No correlation was observed between pT number and BM preservation. The rate of BM preservation in cases of liver metastasis was 84.4%, significantly higher than the rate in cases without liver metastasis (P < 0.001). BM was observed even at the advancing front of tumor invasion and was preserved in 95.0% of the liver metastases. CONCLUSIONS: BM is a functional substance that appears to accompany cancer rather than function as a structural barrier against cancer invasion and liver metastasis.