Are lymph node micrometastases of any clinical significance in dukes stages A and B colorectal cancer?

PURPOSE: The aim was to investigate the significance of lymph node micrometastases in Dukes Stages A and B colorectal cancer. METHODS: Archival specimens were examined from 147 patients (96 colon, 51 rectum; 44 Stage A, 103 Stage B) who had surgery between 1987 and 1994. One lymph node section from each node (colon, 1–11; median, 4; rectum, 1–15; median, 3) was examined with use of an anticytokeratin antibody. RESULTS: Forty-seven (32 percent) patients had micrometastases. At follow-up in June 1996, 23 patients had died of cancer or with known tumor relapse, after a median time of 28 (range, 5–67) months; 8 of 47 (17 percent) patients had micrometastases, 15 of 100 (15 percent) did not. No statistically significant differences were observed according to micrometastases when the results were analyzed with respect to Dukes stage or survival time. The median survival time of living patients with micrometastases was 48 (range, 18–97) months, and for patients without micrometastases, 48 (range, 19–111) months. Six of 96 living patients had a tumor relapse; three of these displayed micrometastases. CONCLUSION: Lymph node micrometastases are not a useful prognostic marker in Dukes Stages A and B and do not imply different strategies for additional therapy or follow-up.This study was supported by the Swedish Cancer Foundation (Project No 2520-B96-10XCC, Project No 3453-B97-05XBB).Read at the Second Surgical Week, Västerås, Sweden, August 18 to 22, 1997.     

Prognostic Significance of Lateral Lymph Node Micrometastases in Lower Rectal Cancer

PURPOSE: The aims of this study were to determine the rate of lymph node micrometastases and to evaluate their prognostic value in lateral lymph nodes in lower rectal cancer at or below the peritoneal reflection. METHODS: A retrospective analysis was made of 892 lymph nodes from 66 consecutive patients who had undergone radical resection with lateral lymph node dissection. These lymph nodes were examined immunohistochemically with an antibody against cytokeratins 7 and 8, CAM5.2. RESULTS: Routine hematoxylin-eosin staining revealed 9 patients with positive lateral lymph nodes that were stained consistently with CAM5.2. Among 57 patients in whom lateral lymph node metastases were not detected by hematoxylin-eosin staining, cytokeratin staining was positive in 19 nodes (2.7 percent) from 11 patients (19.3 percent). These 11 patients with micrometastases in lateral nodes showed a significantly high recurrence rate (P = 0.048) and worse overall survival (P = 0.01) than the 46 patients without lateral node metastases. The recurrence rate and overall survival of patients with micrometastases did not differ significantly from those of patients with positive lateral nodes with hematoxylin-eosin staining. Local recurrence developed in 6 of 66 patients, but neither the presence nor the absence of micrometastases in lateral nodes influenced the local recurrence rate. CONCLUSION: The presence of nodal micrometastases leads to a poor prognosis. The survival of patients with micrometastases was not different from that of patients with overt metastases. Therefore, patients with cytokeratin-positive cells in lateral lymph nodes should be regarded as having overt metastases.     

Prognostic value of micrometastases in esophageal and colorectal carcinoma (a clinical experience)

BACKGROUND/AIMS: The term "micrometastases" has been confused in many aspects. While the influence of lymph node metastases in esophageal and colorectal cancer is well known, the presence and importance of micrometastases is under debate. We investigated micro lymph node invasion in two different kinds of digestive tumors with very high mortality, and identified its possible repercussion on patient survival. METHODOLOGY: Lymph nodes of two groups of patients N0 on routine histopathology after radical resection (R0): 21 with esophageal carcinoma (Group I), and 21 with colorectal carcinoma (Group II), were studied by immunohistochemistry using monoclonal antibodies directed against cytokeratins of wide spectrum. The results were classified as positive or negative and compared with patient survival. RESULTS: Five of twenty-one (5/21) patients in group I and eight of twenty-one (8/21) in group II were positive for micrometastases. Median survival time in the positive esophageal group was 9.5 months vs. 68 in the negative one (p=0.16). Median survival time in the positive subset colorectal group was 54.5 months vs. 76.8 in the negative subgroup (p=0.5). Our results did not show statistical differences in survival time between patients positive or negative for micrometastases; however it is evident, especially in the esophageal cancer group, that there is a negative tendency of positive micrometastases on survival time. CONCLUSIONS: The presence of micrometastases in lymph nodes of patients N0 after conventional histopathology is frequent. Our preliminary results did not allow definitive conclusions but we may suppose its negative influence on patient survival.     

Tumor Invasion of Lymph Node Capsules in Patients with Dukes C Colorectal Adenocarcinoma

Purpose The objective of this study was to investigate the correlation between the microscopic findings of positive lymph nodes, especially focusing on capsular invasion, and the outcome after curative surgical resection of colorectal cancer. Methods We analyzed 480 positive lymph nodes from 155 consecutive patients with Stage III colorectal cancer to determine the frequency and significance of lymph node capsular invasion. Recurrence-free and cancer-specific survival rates were assessed in the patients with and without lymph node capsular invasion. Results Between April 1995 and December 2000, 406 consecutive patients with primary colorectal cancer underwent curative resection. Regional lymph node metastases were present in 155 cases (38.2 percent). During the median follow-up period of 4.8 years, 41 patients (26.5 percent) developed recurrent disease and 28 patients died of cancer. Lymph node capsular invasion was detected in one or more lymph nodes from 75 cases (48.3 percent). The five-year recurrence-free rate was 56.1 percent in this group, whereas in the 80 patients without lymph node capsular invasion the rate was 88 percent (P<0.01). Features that were associated with recurrent disease were greater number of positive lymph nodes, venous invasion in primary tumor, infiltrative growth pattern of intranodal tumor, and presence of lymph node capsular invasion. Multivariate analysis identified lymph node capsular invasion as the only significant prognostic factor for recurrence. In multivariate analysis with regard to survival, lymph node capsular invasion, venous invasion, and number of positive nodes remained as significant prognostic factors. Conclusions Lymph node capsular invasion, determined by routine hematoxylin-eosin staining, is a potent prognostic factor in Stage III colorectal cancer. Read in part at the meeting of The International Society of University Colon and Rectal Surgeons, Budapest, Hungary, June 9, 2004. Reprints are not available.     

癌胚抗原在结直肠癌淋巴结微转移检测中的应用

目的 探讨Ⅰ和Ⅱ期结直肠癌术后病理因素及淋巴结微转移对术后5年无瘤生存率的影响.方法 Ⅰ和Ⅱ期结直肠癌患者共126例,均行结直肠癌根治术.每例结直肠癌患者的淋巴结数平均为16枚(10～28枚),用癌胚抗原(CEA)指标对所有淋巴结进行免疫组化染色.统计分析临床病理因素及微转移对术后5年无瘤生存率的影响.结果 术后平均随访64.11(64～106)个月.淋巴管侵犯和肿瘤侵袭深度与淋巴结的CEA表达呈正相关,而其他临床病理因素与淋巴结CEA表达无明显相关性.10项临床病理因素对5年无瘤生存率的影响差异均无统计学意义(P＞0.05).淋巴结CEA表达阴性、孤立肿瘤细胞巢和微转移患者的5年无瘤生存率分别为75.4%、68.2%和46.2%.孤立肿瘤细胞巢患者与CEA阴性患者5年无瘤生存率比较差异无统计学意义(P=0.245).微转移患者与CEA阴性患者比较,前者5年无瘤生存率明显较低(P=0.003).结论 对于Ⅰ和Ⅱ期结直肠癌,若淋巴结中检测到微转移,其预后较差,术后复发率较高,应予以积极的术后辅助化学治疗.     

Cancer Invasion to Auerbach’s Plexus is an Important Prognostic Factor in Patients with pT3-pT4 Colorectal Cancer

Purpose By defining perineural invasion of colorectal cancer as invasion to Auerbach’s plexus, we examined the usefulness of this pathologic finding as a prognostic factor. Methods A total of 509 consecutive patients who underwent curative surgery for pT3 or pT4 colorectal cancer between May 1997 and December 2001 were reviewed. All the surviving patients were followed for more than five years. All the pathologic findings, including perineural invasion, were described prospectively in the pathology report forms. Results Perineural invasion was detected in 132 of 509 patients (26 percent) and was significantly associated with lymph node status, lymphatic invasion, and venous invasion. Incidences of local and systemic recurrence were significantly higher in patients with perineural invasion than in those without perineural invasion. The disease-free survival of the perineural invasion-positive group was significantly poorer than that of the perineural invasion-negative group for Stages II and III colon cancer, irrespective of the use of adjuvant chemotherapy. This improved disease-free survival also was seen in patients with Stage II rectal cancer not treated with adjuvant chemotherapy. There was a nonsignificant difference in disease-free survival for Stage II rectal cancer and Stage III rectal cancer treated with chemotherapy, that of the perineural invasion-positive group being poorer. Multivariate analysis showed that lymph node status, perineural invasion, depth of invasion, and cancer site were significant prognostic factors. Conclusions Perineural invasion defined as cancer invasion to Auerbach’s plexus is an important prognostic factor for colorectal cancer. Supported by a Grant-in-Aid for Cancer Research from the Ministry of Health, Labor and Welfare of Japan.     

Should carcinoembryonic antigen be used in the management of patients with colorectal cancer?

The contribution of carcinoembryonic antigen carcinoembryionic antigen for the effective management of colorectal cancer patients remains a controversial issue. The aim of this study is to attempt to get some valid answers to its function in the diagnosis, prognosis, and overall management of colorectal cancer patients. METHODS: A retrospective review of colorectal cancer patientsmanaged and prospectively registered by the authors between 1985 and 1998 was performed. Serum carcinoembryionic antigen levels were determined preoperatively in 209 patients with primary colorectal cancer and postoperatively in 196 patients who had undergone curative resection of their tumors, according to a fixed schedule. A maximum value of 5 ng/ml was accepted as being normal. With the exception of endoscopy, all other diagnostic techniques were only used after an abnormal carcinoembryionic antigen result (a raised value found twice consecutively). RESULTS: carcinoembryionic antigen preoperative values were raised only in 40 percent of patients and were related to disease stage, with the highest values found in patients with Stage IV disease. However, an elevated preoperative carcinoembryionic antigen value had a very marked prognostic importance, with a statistically significant difference in survival curves (Kaplan-Meier); the same was valid for curatively resected patients (Stages I, II, and III) and for Stages II and III patients considered separately. Multivariate analysis using the Cox proportional hazards technique confirmed these results, showing preoperative carcinoembryionic antigen to have an independent prognostic value, with a relative risk of recurrence of 3.74 for patients with raised preoperative carcinoembryonic antigen levels. In postoperative follow-up, carcinoembryionic antigen elevation was found to be a very accurate marker of recurrence (sensitivity, 77 percent; specificity, 98 percent), mainly in liver metastasis (sensitivity, 100 percent), and the best marker of asymptomatic recurrence (63 percent of cases). However, carcinoembryionic antigen's impact on overall survival was negligible because of the poor results of surgical treatment of recurrences. CONCLUSIONS: Preoperative carcinoembryionic antigen is a very important prognostic indicator and should be considered in future trials. Postoperative carcinoembryionic antigen elevation is a very sensitive marker of recurrence and even of asymptomatic recurrence, but its impact on overall survival does not seem to be relevant. Nevertheless, carcinoembryionic antigen should continue to be used in colorectal cancer patients until better methods of diagnosis and treatment of recurrence are developed.Presented at the meeting of the American Society of Colon and Rectal Surgeons, San Antonio, Texas, May 2 to 7, 1998.     

Laparoscopic surgery for the cure of colorectal cancer

PURPOSE: The aim of this study was to assess the feasibility and safety of laparoscopic surgery for the cure of colorectal cancer with emphasis on oncologic follow-up in particular. METHODS: A study was performed of patients with colorectal cancer treated by laparoscopy in five German centers between May 1991 and September 1997. Surgical and pathologic data were recorded in an anonymous registry database and analyzed by type of resection. Standard procedures were sigmoid or left colectomy, anterior resection, abdominoperineal resection, and right hemicolectomy. Follow-up information included incidence of local, distant, and port site recurrence and cancer-related death. RESULTS: A total of 399 patients (212 females) with a mean age of 66.6 years underwent laparoscopic curative resections (sigmoid resection, 89; left colectomy, 11; anterior resection, 157; abdominoperineal resection, 102; right hemicolectomy, 40). Conversion was necessary in 6.3 percent (n=25). Complications requiring reoperation occurred in 9 percent (n=35). Complications that were treated conservatively occurred in 27.6 percent (n=110). Thirty-day mortality was 1.8 percent (n=7). First bowel movements resumed on the third postoperative day; patients did not use analgesics after a mean of five days. Mean postoperative hospitalization was two weeks. According to International Union Against Cancer classification, 147 patients had Stage I cancer, 35 had Stage II cancer, and 217 underwent curative resection for Stage III cancer. Mean number of lymph nodes resected was 12.1. At a mean follow-up of 30 months, one port site recurrence was documented. No local recurrence was observed after curative resection of Stage I colorectal cancer. Of 399 patients, local recurrence occurred in 6 patients (Stage II, 2; Stage III, 4), and distant metastases were documented in 25 patients (Stage I, 3; Stage II, 3; Stage III, 19). The highest incidence of cancer-related death occurred after abdominoperineal resection (4.9 percent). CONCLUSION: To assess the role of laparoscopic colorectal surgery for the cure of cancer objectively, prospective randomized trials are necessary.Read at the meeting of The American Society of Colon and Rectal Surgeons, San Antonio, Texas, May 2 to 7, 1998.     

Sentinel Node Mapping does not Improve Staging of Lymph Node Metastasis in Colonic Cancer

Purpose  This study was designed to evaluate the reliability of the sentinel node concept in colonic cancer. Methods  Patent blue was used as tracer. The four blue nodes closest to the tumor were defined as the sentinel node(s) by the pathologist. All nodes were examined by routine microscopy (hematoxylin-eosin staining). If no metastases were detected, all lymph nodes were examined immunohistochemically with antibody to cytokeratin. Results  Two hundred colon specimens were examined. Sentinel node(s) were identified in 93 percent. Sixty contained metastases in hematoxylin-eosin sections. In 32 these were found in sentinel nodes (sensitivity 53 percent). Twenty-eight patients had metastases in nonsentinel nodes only, giving a false-negative rate of 47 percent. Immunostaining revealed 39 (30 percent) micrometastases or submicrometastases in 131 TNM Stages I and II patients, and in 17 of these patients metastases were found in nonsentinel nodes only (false-negative rate 44 percent). Conclusions  Sentinel lymph node mapping shows low sensitivity for detection of ordinary metastases, micrometastases, and submicrometastases. If only the sentinel nodes had been examined, approximately half of the metastases would have been lost after routine staining, as well as half of the micrometastases and submicrometastases when immunohistochemical examination was added. Presented as one of six best papers at the meeting of the European Society of Coloprotology-ESCP, Portomaso, Malta, September 26 to 29, 2007. An erratum to this article can be found at     

Tumour-derived mutated K-ras codon 12 expression in regional lymph nodes of stage II colorectal cancer patients is not associated with increased risk of cancer-related death

This study examined the frequency of lymph node micrometastases detected by expression of mutant K-ras oncogene present in the respective primary tumour. The study population consisted of consecutive patients with stage II colorectal cancer (CRC) undergoing curative resection and with disease-free survival of 60 months or longer or CRC-related death. Of 27 patients found to have K-ras mutations at codon 12, 17 had genomic DNA suitable for PCR recovered from corresponding regional lymph node tissue. The same K-ras mutation was identified in the lymph nodes of 13 patients (76%), four of whom (30%) died of CRC recurrence within 5 years. A single patient in the negative group (25%) also died. Lymph node micrometastases detected by this technique thus show no relationship to mortality in stage II CRC. Further study of this technique is necessary before it can be used in the selection of patients for adjuvant chemotherapy.     

POSSUM Predicts Decreased Overall Survival in Curative Resection for Colorectal Cancer

Purpose Poor condition at operation determined by the physiologic POSSUM score is related to postoperative mortality and morbidity of colorectal cancer surgery. This study was designed to analyze the relationship between condition of patients with colorectal cancer at operation and long-term overall survival. Methods A total of 542 patients survived a radical resection for Stages I, II, or III colorectal cancer. Physiologic POSSUM score at surgery, exclusive of age, was calculated for all patients. Mean physiologic POSSUM score was used as cutoff point to determine low-risk and high-risk group patients. A Cox proportional hazard analysis was performed to study the effect of low-risk and high-risk group on overall survival and to identify independent risk factors. Results Five-year overall survival was significantly higher in low-risk group patients than in high-risk group patients (low-risk group 66.6 percent vs. high-risk group 48.5 percent; P < 0.001). Differences in overall survival also were found when patients in Stages I, II, and III were analyzed separately. Risk factors for overall survival were advanced stage of disease, poor tumor differentiation, mucinous adenocarcinoma, older than age 70 years, and poor condition of the patient at time of operation. Conclusions Poor condition at operation, as determined by physiologic POSSUM score, is a risk indicator for long-term overall survival in colorectal cancer patients. Poster presentation at the meeting of the European Association of Coloproctology, Geneva, Switzerland, September 16 to 18, 2004. Reprints are not available.     

Indication and Benefit of Pelvic Sidewall Dissection for Rectal Cancer

Purpose This study was designed to clarify indication and benefit of pelvic sidewall dissection for rectal cancer. Methods The retrospective, multicenter study collected the data of rectal cancer patients who underwent surgery between 1991 and 1998 and were prospectively followed. Results Of 1,977 patients with rectal cancers, 930 underwent pelvic sidewall dissection without adjuvant radiotherapy. Positive lateral lymph nodes were found in 129. Multivariate analysis disclosed a significantly increased incidence of positive lateral lymph nodes in female gender, lower rectal cancers, non-well-differentiated adenocarcinoma, tumor size of ≥4 cm and T3-T4. The five-year survival rate for 1,977 patients was 79.7 percent. The survival of patients with positive lateral lymph nodes was significantly worse than that of Stage III patients with negative lateral lymph nodes (45.8 vs. 71.2 percent, P<0.0001). Multivariate analysis showed significantly worse prognosis in male gender, pelvic sidewall dissection, lower rectal cancers, T3-T4, perirectal lymph node metastasis, and positive lateral lymph nodes. During the median follow-up time of 57 months, recurrence developed in 19.7 percent: 17 percent in negative and 58.1 percent in positive lateral lymph nodes (P<0.0001). Local recurrence was found in 8 percent: 6.8 percent in negative and 25.6 percent in positive lateral lymph nodes (P<0.0001). Multivariate analysis disclosed that lower rectal cancers, non-well-differentiated adenocarcinoma, T3-T4, perirectal lymph node metastasis, and positive lateral lymph nodes were significantly associated with an increased local recurrence. Conclusions Positive lateral lymph node was the strongest predictor in both survival and local recurrence. Pelvic sidewall dissection may be indicated for patients with T3-T4 lower rectal cancers because of the greater provability of positive lateral lymph nodes. Study Group for Rectal Cancer Surgery of the Japanese Society for Cancer of the Colon and Rectum. Presented at the United States-Japan Clinical Trial Summit Meeting, Maui, Hawaii, February 10–13, 2005.     

Lateral lymph node dissection for lower rectal cancer

BACKGROUND/AIMS: This study was conducted to evaluate the effects of lateral lymph node dissection (LLD) on overall survival, disease-free survival, and local recurrence for the patients with lower rectal cancer. METHODOLOGY: From 1990 through 2000, 169 consecutive patients with T2 (TNM classification) or more advanced, extended lower rectal cancer (located below the peritoneal reflection) underwent curative resection at Kanagawa Cancer Center were reviewed. One hundred and forty-three patients who underwent LLD and the 26 patients who did not were entered in this study. RESULTS: Cox's multivariate regression analysis showed T stage (TMN classification), N stage (TNM classification), and LLD were found to be significantly related to the rates of both cumulative survival and disease-free survival. That mean LLD was identified as a significant prognostic factor. But disease-free survival did not differ significantly between the patients who underwent LLD and those who did not undergo LLD in stage I, II, or III disease (p = 0.3681, p = 0.1815, and p = 0.0896, respectively). The local recurrence rate was similar in patients who received LLD (17.5 percent) and in those who did not receive LLD (23.1 percent; p = 0.498). But 7 patients with lateral lymph node metastasis (33.3 percent) remained disease free. And these patients had local lateral lymph node metastasis and benefited from LLD. CONCLUSIONS: LLD can substantially improve outcomes in selected patients at high risk for lateral lymph node metastasis. A randomized controlled clinical study is necessary to clarify the role of LLD in the treatment of rectal cancer.     

Expression of nm23-H1 predicts lymph node involvement in colorectal carcinoma

PURPOSE: Reduced expression of the metastasis suppressor gene nm23-H1 has previously been correlated with high tumor metastatic potential and fatal clinical outcome in some tumors (e.g.,breast). For colorectal carcinomas, the findings are equivocal. METHODS: We have used a monoclonal antibody against nm23-H1 to investigate the expression in colorectal carcinomas at the time of primary curative surgery (RO resection) to assess if there was any relation between nm23-H1 expression and stage or histologic grade at the time of primary tumor removal. RESULTS: Of 100 colorectal carcinomas studied (Stages I, II, and III according UICC, all resected curatively), nm23-H1 immunoreactivity was weak in 41 (41 percent), moderate in 24 (24 percent), and strong in 35 (35 percent) cases. The grade of positivity against nm23-H1 was significantly lower in advanced stages of the disease (Stages II or III) (P < 0.001, chi-squared=52.8). In tumors with low or weak immunoreactivity against nm23-H1, frequency of lymph node metastases was significantly higher compared with those with moderate or strong staining (P < 0.001; chi-squared=50.58). Therefore, with a sensitivity of 93 percent and a specificity of 58 percent, low nm23-H1 immunoreactivity of the primary tumor, assessed at the time of surgery, is an indicator of the presence of lymph node metastases. CONCLUSIONS: Immunohisto-chemical evaluation of nm23-H1 in the primary tumor or in a biopsy is a useful predictor of stage of disease and presence of lymph node metastases in colorectal carcinomas and may have clinical significance,e.g.,in predicting optimal therapeutic regimes.     

A Pathologic Complete Response to Preoperative Chemoradiation Is Associated With Lower Local Recurrence and Improved Survival in Rectal Cancer Patients Treated by Mesorectal Excision

PURPOSE: Preoperative chemoradiation reduces tumor size and nodal metastasis in patients with rectal cancer. Tumor downstaging has been associated with an increased probability of a sphincter-saving procedure and with improved local control. However, pathologic complete response to chemoradiation has not been correlated with local control and patient survival. We studied the prognostic value of pathologic complete response to preoperative chemoradiation in rectal cancer patients. METHODS: We have prospectively followed up 168 consecutive patients with ultrasound Stages II (46) and III (122) rectal cancer treated by preoperative chemoradiation followed by radical resection with mesorectal excision; 161 had a curative resection. Recurrence and survival were compared with tumor characteristics and pathologic complete response. Average follow-up was 37 months. RESULTS: Tumor downstaging occurred in 97 (58 percent) patients, including 21 (13 percent) patients who had a pathologic complete response. None of the clinical or pathologic variables was associated with pathologic complete response. The estimated 5-year rate of local recurrence was 5 percent; of distant metastasis, 14 percent. None of the patients with pathologic complete response has developed disease recurrence. We found no difference in survival among patients with pathologic Stages I, II, or III tumors. CONCLUSIONS: A pathologic complete response to preoperative chemoradiation is associated with improved local control and patient survival. For patients without pathologic complete response, the pathology stage does not have prognostic significance.     

Comparative Analysis of Nodal Upstaging Between Colon and Rectal Cancers by Sentinel Lymph Node Mapping: A Prospective Trial

PURPOSE Sentinel lymph node mapping accurately predicts nodal status in >90 percent of melanoma and breast and colorectal cancers. However, because of anatomic differences, sentinel lymph node mapping of rectal cancers has been considered inaccurate and difficult relative to colon. A prospective study was undertaken to identify differences in sentinel lymph node mapping between patients with colon cancer and those with rectal cancer.METHODS At operation 1 to 3 ml of 1 percent isosulfan blue dye was injected subserosally around colon cancers. The first to fourth blue-staining nodes seen within ten minutes of injection were marked as sentinel lymph nodes. For cancer of the mid-rectum to low rectum, the dye was injected submucosally via rigid scope and spinal needle. The mesorectum was dissected ex vivo to identify blue nodes nearest the tumor as sentinel lymph nodes. Multilevel microsections of sentinel lymph nodes were stained with hematoxylin and eosin and immunostained for cytokeratin, and standard examination of the entire specimen was performed.RESULTS There were 407 consecutive patients (336 with colon and 71 rectum). The sentinel lymph nodes were identified in 99.1 percent of colon and 91.5 percent of rectal patients (P < 0.0001). Skip metastases were found in 3.6 percent of colon vs. 2.8 percent of rectal patients (P = 0.16). Occult micrometastases were found in 13.4 percent of colon vs. 7.0 percent of rectal patients (P = 0.24). Except for success rates, no other parameters were statistically different between colon and rectum. Lower success in sentinel lymph node identification in rectal cancer may have been related to neoadjuvant chemoradiation received in all six of the patients with sentinel lymph node mapping failures.CONCLUSION Despite higher success rates in sentinel lymph node identification for colon patients, sentinel lymph node mapping was highly successful (91.5 percent) in rectal patients. Nodal upstaging, skip metastases, and occult metastases were similar.Read at the meeting of the American Society of Colon and Rectal Surgeons, New Orleans, Louisiana, June 21 to 26, 2003.     

Histopathologic characteristics of colorectal cancer with liver metastasis

PURPOSE: Although prognostic factors of colorectal cancer have been studied, factors associated with liver metastasis have not been fully investigated. The aim of this study was to clarify the histopathologic characteristics of colorectal cancer with liver metastasis. METHODS: We performed a retrospective histopathologic study on 335 patients who underwent resection of colorectal cancer during 15 years. Histopathologic parameters of tumors with liver metastasis were compared with those without liver metastasis. RESULTS: Forty-one patients (12 percent) had simultaneous liver metastasis. Tumors having liver metastasis, when compared with those not having liver metastasis, were characterized by high frequency of tumor size more than 6 cm (51vs. 28 percent;P<0.01), presence of serosal invasion (98vs. 66 percent;P<0.01), lymphatic invasion (34vs. 15 percent;P<0.01), venous invasion (24vs. 3 percent;P<0.01), and lymph node metastasis (85vs. 39 percent;P<0.01). Multivariate analysis showed that factors independently associated with liver metastasis were serosal invasion, venous invasion, and lymph node metastasis. Accuracy in the diagnosis of liver metastasis was highest for venous invasion (88 percent) and lowest for serosal invasion (41 percent). Among 98 patients with both serosal invasion and lymph node metastasis, tumors with and without liver metastasis were different in frequency of venous invasion (26vs. 6 percent;P<0.01) and extracolic lymph node metastasis (68vs. 47 percent;P<0.05). CONCLUSION: In colorectal cancer important factors associated with liver metastasis were serosal invasion, venous invasion, and lymph node metastasis. Significant determinants for liver metastasis from colorectal cancer were venous invasion and extracolic lymph node metastasis.Presented at the meeting of The Japanese Society for Cancer of the Colon and Rectum, Tokyo, Japan, July 4, 1997.     

Results from pelvic exenteration for locally advanced colorectal cancer with lymph node metastases

PURPOSE: We examined the survival benefit of pelvic exenteration for locally advanced colorectal cancer with lymph node metastases, because this issue remains controversial. METHODS: Medical records of 50 patients who underwent curative pelvic exenteration for colorectal cancer were reviewed retrospectively. Nodal metastases were examined by the clearing method in 29 patients and by the conventional manual method in 21 patients. RESULTS: Invasion to contiguous pelvic organs was present in 40 patients (80 percent) and absent in 10 patients (20 percent). Node metastases were present in 33 patients (66 percent). Operative morbidity and mortality rates were 22 percent (11 patients) and 6 percent (3 patients), respectively. Respective five-year survival rates were 60 and 80 percent in the groups with and without organ invasion (no significant difference). Five-year survival rates in patients with nodal metastases was 54.6 percent but was significantly higher, 82.4 percent, in patients without nodal metastases. Five-year survival in 28 patients with both organ invasion and nodal metastases was 53.6 percent. CONCLUSIONS: Long-term survival was afforded by pelvic exenteration for locally advanced colorectal cancer with nodal metastases.