Changing site distribution of colorectal cancer in Japan

PURPOSE: In North America and other high-risk areas, there has been a proximal shift in the subsite distribution of colorectal cancer. We wanted to determine whether any similar change has occurred in Japan, and where the incidence of this disease has increased sharply. METHODS: Data from the Reports of the Japanese Society for Cancer of the Colon and Rectum were used to analyze the time trend of colorectal cancer in Japan between 1974 and 1994 according to the patients age at diagnosis and sex, and the site of the tumor within the colon or rectum. RESULTS: The percentage of patients over the age of 70, especially females, increased. The increase in the percentage of right-sided colon cancer in colorectal cancer cases was accompanied by a continuous decline in the percentage of rectal cancer in both sexes at all ages. In general, the percentage of right-sided colon cancer in colon cancer cases was stable in men, but increased in women. The rate among patients older than 70 years increased in men, but predominated and remained stable in women. No proximal shift in colon cancer was found in either sex under the age of 69. CONCLUSION: These findings indicated that a proximal shift in the subsite distribution of colorectal cancer has occurred in Japan. This rightward shift of colorectal cancer is due to the decreasing proportion of rectal cancer. Furthermore, the increasing proportion of older patients, especially females, may be another major determinant of the changing colon cancer subsite distribution.     

Outcome of surgery for colorectal cancer in a defined population in Sweden from 1984 to 1986

PURPOSE: This study was designed to investigate incidence, treatment, and outcome for patients with colorectal cancer. METHODS: From 1984 to 1986 in Östergötland, a county in Sweden with a defined population, a prospective registration using a computerized protocol was undertaken. RESULTS: In the surgical departments 596 cases were diagnosed and 31 more cases were diagnosed in other departments, bringing the incidence to 53 cases per 100,000 inhabitants per year. Of the cases, 14 percent presented as emergencies. The resectability rate was 90 percent, and the rate of curative operations was 74 percent. Postoperative mortality within 30 days was 2.9 percent. Crude five-year survival for all patients was 40 percent, and the corrected survival rate was 53 percent. After curative resection the crude five-year survival rate was 53 percent, and the corrected survival rate was 70 percent. Prognosis was better for colon than for rectal cancer, 76 percent vs.59 percent corrected five-year survival rate. For rectal cancer the local recurrence rate was 20 percent after curative resection. CONCLUSIONS: The prognosis was improved compared with a previous study from the same area because of decreased postoperative mortality, increased rate of operations for cure, and an increased five-year corrected survival rate. Local recurrence after rectal cancer was still high but may be reduced with improved surgical technique.Supported by grants from Östergötlands Läns Landsting (Project 52/82, 49/83, and 51/84).     

Analysis of regional lymph node metastases from rectal carcinoma by the clearing method

PURPOSE: It has been reported that functional outcome following low anterior 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.Supported, in part, by a Grant-in-Aid for Cancer Research from the Japanese Ministry of Health and Welfare and Scientific Research from the Japanese Ministry of Education, Culture and Science.     

Double-barreled wet colostomy

An easy and simple method for constructing a urinary diversion in patients undergoing pelvic exenteration for advanced rectal cancer is described. This procedure features double-barreled colostomy with a segment of the sigmoid colon 8 to 10 cm distal to the stoma as a urinary conduit.Read at the meeting of the Japanese Research Society for Cancer of the Colon and Rectum, Tokyo, Japan, July 29, 1994.     

The changing distribution and survival of colorectal carcinoma: an epidemiological study in an area of northern Italy

OBJECTIVE: This study analyses the inter-relations of anatomical tumour location, gender, age and incidence rates for colorectal cancer from 1978 to 1999 in an area of northern Italy: the Parma district. METHODS: Data were obtained from the Parma Cancer Registry. Age-adjusted incidence rates were analysed by gender, age and colorectal cancer subsites. In addition, 5 year observed survival rates were determined. RESULTS: In the Parma area, the incidence of colorectal cancer is rising. We have observed a true increase in the rate of the age standardized incidence of right colon cancer, linked to an increased incidence of left colon cancer, while the incidence of rectal cancer has remained constant. The frequency of right-sided colon cancer was higher in aged patients, and in women. Age-standardized relative survival of patients after diagnosis of colorectal cancer between 1992 and 1996 was found to be significantly higher than age-standardized relative survival after diagnosis between 1978 and 1982. CONCLUSIONS: In the Parma area there has been an increased incidence of right colon cancer, linked to an increased incidence of left colon cancer, while the incidence of rectal cancer has remained constant. We feel that this shift, whatever the reason for it, has important implications for the choice of screening techniques.     

DNA Ploidy Status and Prognosis in Colorectal Cancer: A Meta-Analysis of Published Data

Purpose In colorectal cancer, the negative effect of aneuploidy has been a controversy for more than 20 years. Studies to determine a survival-deoxyribonucleic acid content relationship have conflicting results. A systematic literature search followed by a meta-analysis of published studies addressing prognostic effect of aneuploidy for patients who underwent surgical treatment of colon and rectal cancer was conducted. Methods The main outcome measure was the five-year overall mortality rate after surgical resection. For the selected studies, we estimated this outcome for three subsets of patients through separate meta-analyses: 1) for all patients with colorectal cancer; 2) only between patients with Stage II colon cancer; and 3) only for studies in which follow-up losses were declared. The presence of publication bias was assessed with a funnel plot for asymmetry. Results A total of 5,478 patients with colorectal cancer were represented in 32 studies (Group 1), we estimated a reduction in the five-year overall mortality from 43.2 percent for aneuploid tumors to 29.2 percent for diploid tumors (combined relative risk = 1.44; 95 percent confidence interval = 1.34–1.55; P < 0.001). In addition, 357 patients with Stage II colon cancer (Group 2) extracted from three studies had an absolute reduction of 14.3 percent in five-year overall mortality favoring diploid tumors (combined relative risk = 1.93; 95 percent confidence interval = 1.29–2.89; P = 0.001). Lastly, of 14 studies in which follow-up losses were declared (Group 3), 2,221 patients were represented and a 15.7 percent mortality reduction was measured favoring patients with diploid tumors (combined relative risk = 1.44; 95 percent confidence interval = 1.3–1.61; P < 0.001). Conclusions Patients who undergo an aneuploid colorectal cancer surgical resection have a higher risk of death after five years. This finding may ultimately impact survival of patients with node-negative colon cancer through adjuvant therapy. Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 3 to 7, 2006.     

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.     

Adjuvant chemotherapy in colorectal carcinoma

Despite the National Institutes of Health consensus regarding use of adjuvant chemotherapy in colorectal carcinoma, many general surgeons question the efficacy of this approach when considering costs involved for both the individual patient and society at large. PURPOSE: This study was designed to determine the real impact of adjuvant chemotherapy on five-year survival rates of patients. METHOD: A qualitative and quantitative meta-analysis of results from 39 randomized clinical trials published from 1959 to 1993 is described. RESULTS: Design quality of clinical trials had a mean score of 48.6 percent (±6.2 standard deviation). A small benefit of therapy in terms of overall survival was noted, with a mortality odds ratio (OR) of 0.91 (confidence interval (CI) 95 percent, 0.83–0.99). For the group of colon carcinomas, the OR was 0.81 (CI 95 percent, 0.69–0.94) with an OR of 0.64 (CI 95 percent, 0.48–0.85) for the group of rectal carcinomas. The effect size was 0.09 for the colon group and 0.20 for the rectal group. For those patients who receive chemotherapy, this effect size implies that we can expect an increase of 5 percent in the survival rate in the group with colon carcinoma and a 9 percent increase in the survival rate in the group with rectal carcinoma. CONCLUSION: Given the high incidence of colorectal carcinoma, the small benefit observed for those patients receiving chemotherapy is far from negligible. However, indications for adjuvant chemotherapy warrant further discussion.Read at the meeting of The American Society of Colon and Rectal Surgeons, Montreal, Quebec, Canada, May 7 to 12, 1995.     

A Patient's Race/Ethnicity Does Not Explain the Underuse of Appropriate Adjuvant Therapy in Colorectal Cancer

Introduction To improve colorectal cancer outcomes, appropriate adjuvant therapy (chemotherapy, radiation therapy) should be given. Numerous studies have demonstrated underuse of adjuvant therapy in colorectal cancer. The current study examines variables associated with underuse of adjuvant therapy. Methods Three population-based databases were linked: California Cancer Registry, California Patient Discharge Database, 2000 Census. All colorectal cancer patients diagnosed from 1994 to 2001 were studied. Patient characteristics (age, gender, race/ethnicity, comorbidities, payer, diagnosis year, socioeconomic status) were used in five multivariate regression analyses to predict receipt of chemotherapy for Stage III colon cancer, and receipt of chemotherapy and radiation therapy for Stages II, III rectal cancer. Results The overall cohort was 18,649 Stage III colon cancer and Stages II, III rectal cancer patients. Mean age was 68.9 years, 50 percent male, 74 percent non-Hispanic white, 6 percent black, 11 percent Hispanic, 9 percent Asian, and 65 percent had no significant comorbid disease. Receipt of chemotherapy was 48 percent for Stage III colon cancer, 48 percent for Stage II rectal cancer, and 66 percent for Stage III rectal cancer. Receipt of radiation therapy was 52 percent for Stage II rectal cancer and 66 percent for Stage III rectal cancer. In all five models, low socioeconomic status predicted underuse of chemotherapy or radiation therapy (P < 0.016). Race/ethnicity was not statistically associated with underuse in any of the models. Conclusions Most literature identifies race/ethnicity as the reason for disparate receipt of adjuvant therapy in colorectal cancer. Using a more robust database of three population-based sources, our analysis demonstrates that socioeconomic status is a more important predictor of (in)appropriate care than race/ethnicity. Explicit measures to improve care to the poor with colorectal cancer are needed. Supported by Limited Project Grant from The American Society of Colon and Rectal Surgeons; Asian American Network for Cancer Awareness, Research, and Training Grant from the National Cancer Institute (#5U01CA086322-06); and the Robert Wood Johnson Clinical Scholars Program at UCLA. Read at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, April 30 to May 5, 2005; Recipient of the Piedmont Society of Colon and Rectal Surgeons Awards for Clinical Podium Presentation. Reprints are not available.     

Colorectal carcinoma: recent advances in its biology and treatment

Recent advances in the molecular biology and treatment of rectal carcinoma were reviewed mainly on the basis of our own experience. Remarkable improvement in molecular biology has been achieved in the colorectal diseases, and the new knowledge derived from molecular genetics is now being used in the clinical field. The deeper understanding of colorectal carcinogenesis and wider clinical use of molecular diagnosis is one of the examples, and further advances are expected in the next century. Surgical advances are noted particularly in the field of rectal surgery. Various modalities make it possible to assess the clinical stage more precisely, which leads to careful application of the fine surgical procedures used to maintain urinary and sexual functions with low rates of local recurrence and prolonged survival. This decision making should be conducted and can be accomplished by experienced colorectal surgeons with the team members supporting them. The earlier the detection of disease, the easier the operation, with a lower risk of recurrence and longer survival; therefore, early detection of colorectal cancer by means of occult blood test is essential for this purpose. Establishment of the proper training system for appropriate colorectal surgery is also mandatory for this most common gastrointestinal cancer in the Western world, and this is also the case for Japan. The Japan Society for Cancer of the Colon and Rectum is expected to play an important role in this respect. Received: 30 November 1998 / Accepted: 1 February 1999     

Increasing incidence and excellent survival of patients with early gastric cancer: experience in a United States medical center

PURPOSE: In Japan, early gastric cancer has an excellent survival rate. In the United States, the disease is less well understood, and it is viewed more pessimistically, although we have previously shown in a small series of patients good short-term survival rates in early gastric cancer as compared with advanced gastric cancer. Our purpose in this study was to determine if the incidence of early gastric cancer and the associated survival rate has changed over a 24-year period. PATIENTS AND METHODS: From the records at the Columbia Presbyterian Medical Center, 549 patients were identified who underwent gastric resection for cancer between 1960 and 1984, 69 of whom had early gastric cancer. Survival data were obtained in 63 patients. A comparison of survival rates was conducted between patients with early gastric cancer and the 1980 census figures. RESULTS: Over the 24-year period, the total number of resections for gastric cancer at our institution declined. However, the percentage of gastric resections that satisfied the Japanese criteria for early gastric cancer increased from 9 percent between 1960 to 1974 to 17 percent between 1975 to 1984 (p less than 0.05). Of the 69 early gastric cancers, 35 percent involved the mucosa, whereas in 65 percent the malignancy invaded the submucosa. Twenty-eight percent had lymph node involvement. For the patients for whom survival data were available, survival was better than the 1980 census (p less than 0.05). The adjusted five-year survival rate was 97 percent. Neither submucosal invasion nor lymph node involvement altered survival. Patients with type III early cancers (ulcerated), however, had a significantly greater survival rate than patients with type I (polypoid) early cancers (p less than 0.05). CONCLUSION: Early gastric cancer is being diagnosed with increasing frequency and has an excellent survival rate. These findings are similar to the Japanese experience and argue for an ongoing aggressive approach to endoscopic biopsy of gastric lesions.     

Is local excision adequate therapy for early rectal cancer?

PURPOSE: Radical surgery of rectal cancer is associated with significant morbidity, and some patients with low-lying lesions must accept a permanent colostomy. Several studies have suggested satisfactory tumor control after local excision of early rectal cancer. The purpose of this study was to compare recurrence and survival rates after treating early rectal cancers with local excision and radical surgery. METHODS: One hundred eight patients with T1 and T2 rectal adenocarcinomas treated by transanal excision were compared with 153 patients with T1N0 and T2N0 rectal adenocarcinomas treated with radical surgery. Neither group received adjuvant chemoradiation. Mean follow-up time was 4.4 years after local excision and 4.8 years after radical surgery. RESULTS: The estimated five-year local recurrence rate was 28 percent (18 percent for T1 tumors and 47 percent for T2 tumors) after local excision and 4 percent (none for T1 tumors and 6 percent for T2 tumors) after radical surgery. Overall recurrence was also higher after local excision (21 percent for T1 tumors and 47 percent for T2 tumors) than after radical surgery (9 percent for T1 tumors and 16 percent for T2 tumors). Twenty-four of 27 patients with recurrence after local excision underwent salvage surgery. The estimated five-year overall survival rate was 69 percent after local excision (72 percent for T1 tumors and 65 percent after T2 tumors) and 82 percent after radical surgery (80 percent for T1 tumors and 81 percent for T2 tumors). Differences in survival rate between local excision and radical surgery were statistically significant in patients with T2 tumors. CONCLUSIONS: Local excision of early rectal cancer carries a high risk of local recurrence. Salvage surgery is possible in most patients with local recurrence, but may be effective only in patients with T1 tumors. When compared with radical surgery, local excision may compromise overall survival in patients with T2 rectal cancers.Supported by Minnesota Colon and Rectal Foundation and TUMORS database.Read at The American Society of Colon and Rectal Surgeons' 100th Anniversary and Tripartite Meeting, Washington, D.C., May 1 to 6, 1999.     

Characteristics and Survival Patterns of Solid Organ Transplant Patients Developing <Emphasis Type="Italic">De Novo</Emphasis> Colon and Rectal Cancer

PURPOSE Immunosuppression used in transplantation is associated with an increased incidence of various cancers. Although the incidence of colorectal cancer in transplant patients seems to be equal to nontransplant population, the effects of immunosuppression on patients who develop colorectal cancer are not well defined. The purpose of this study was to define the characteristics and survival patterns of transplant patients developing de novo colorectal cancer.METHODS The Israel Penn International Transplant Tumor Registry was queried for patients with colorectal cancer. Analysis included patient demographics, age at transplantation and colorectal cancer diagnosis, tumor stage, and survival. Age and survival rates were compared to United States population-based colorectal cancer statistics using the National Cancer Institute Surveillance Epidemiology and End Results database.RESULTS A total of 150 transplant patients with de novo colorectal cancer were identified: 93 kidney, 29 heart, 27 liver, and 1 lung. Mean age at transplantation was 53 years. Age at transplantation and colorectal cancer diagnosis was not significant for gender, race, or stage of disease. Compared to National Cancer Institute Surveillance Epidemiology and End Results database, transplantat patients had a younger mean age at colorectal cancer diagnosis (58 vs. 70 years; P < 0.001), and a worse five-year survival (overall, 44 vs. 62 percent, P < 0.001; Dukes A&B, 74 vs. 90 percent, P < 0.001; Dukes C, 20 vs. 66 percent, P < 0.001; and Dukes D, 0 vs. 9 percent, P = 0.08). CONCLUSIONS Transplant patients develop colorectal cancer at a younger age and exhibit worse five-year survival rates than the general population. These data suggest that chronic immunosuppression results in a more aggressive tumor biology. Frequent posttransplantation colorectal cancer screening program may be warranted.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, New Orleans, Louisiana, June 21 to 26, 2003.     

Subsite distribution and incidence of colorectal cancer in New Zealand, 1974–1983

The purpose of this study was to examine changes in subsite distribution and incidence of colorectal cancer within different age groups. Registration of colorectal cancer by the National Cancer Registry of New Zealand approached 100 percent by 1974. The present study was based on 15,395 individuals aged 25 years and over and registered for colorectal cancer between 1974 and 1983. Subsite distribution (right colon, left colon, rectum) for different age groups (25–49, 50–69, 70+ years) was significantly skewed, with an excess of right colonic cancer in individuals aged 25–49 years and 70+ years. This right colonic excess was accompanied by a relative reduction in left colonic cancer. Age adjusted incidence rates for the periods 1974–78 and 1979–83 were compared and stratified by age group and subsite. Incidence rates increased in all subsites in individuals aged 50+ years. This was particularly evident for right sided cancer in the elderly of both sexes. There was a marked reduction in the incidence of left colonic cancer and rectal cancer in individuals under 50 years. In contrast, the incidence of right colonic cancer remained relatively stable in young individuals. Time trend studies indicate that the skewed subsite distribution of large bowel cancer in different age groups may increase with time and is probably due to varying etiological factors acting on different cohorts.The author thanks Mr. J. Fraser and the staff of the National Cancer Registry of New Zealand for their valuable assistance and Professor R. Beaglehole of the Department of Community Health, University of Auckland School of Medicine, for his helpful comments.     

Survival in patients with large-bowel cancer

Five-year survival data were obtained in 97 percent or 1105 of 1140 new patients with histologically confirmed colorectal adenocarcinoma during a 12-month period in 1981 and 1982, as part of a large comprehensive population-based study of colorectal cancer incidence, etiology, and survival, The Melbourne Colorectal Cancer Study. Fifteen percent of patients were Dukes' A stage, 32 percent were Dukes' B, 25 percent were Dukes' C, and 29 percent were Dukes' D. At five years after diagnosis, the observed survival rate was 36 percent and the adjusted rate was 42 percent. Dukes' staging was a highly discriminating factor in survival (P less than 0.001). Survival rates were better in women than in men and better for patients with colon cancer than for patients with rectal cancer. Survival by Dukes' staging was not affected by colon subsite or by the tumor being the first and single tumor, metachronous tumor, or synchronous tumor. The survival of younger patients was better for Dukes' stages A, B, and C, and worse for Dukes' D. Survival was worse in the presence of bowel perforation in Dukes' C and D stages. Within Dukes' D (incurable cases), survival was best in the absence of hepatic metastases, slightly worse when only hepatic metastases were present, and poorest in the presence of both hepatic and extrahepatic metastases. Statistical modeling of survival determinants other than staging indicated that cell differentiation had the largest effect (survival decreasing with poor cell differentiation), followed by site (survival worse for rectal cancer than colon cancer), then age (survival better for younger patients), while bowel perforation had the smallest effect on survival.     

Trends in colorectal incidence by anatomic subsite from 1985 to 2005: a population-based study

Background

Conflicting results on the shift of right–left ratio in colon cancer incidence have been reported. We examine incidence trends by subsite in a population-based study.

Materials and methods

Colorectal cancer cases diagnosed in the 1985–2005 period were identified through the Tuscany Cancer Registry. Colon subsite was defined as proximal and distal; gender, age at diagnosis, histology, and stage were analyzed. Average annual incidence and age-specific rates according to subsite were calculated.

Results

A total of 21,160 colorectal cancer cases were extracted; in 18,311 cases, the subsite was identified: 6,916 rectal, 5,239 proximal, and 6,156 distal. A larger proportion of distal colon cancers presented as early stage when compared with proximal. Incidence of rectal and distal colon cancer remained stable, while proximal colon cancer incidence increased.

Conclusions

Proximal colon cancer incidence rate increased through the period. Temporal variations in the incidence rate by subsite could suggest different carcinogenic pathways of right- and left-sided colon cancer.     

Treatment of primary colon cancer with peritoneal carcinomatosis: comparison of concomitant vs. delayed management

PURPOSE: The initial dissemination of colon cancer occurs through three routes: the lymphatics, the portal blood, and the peritoneal surfaces. Although lymphatic and hematogenous metastases indicate an aggressive disease process, it is possible that dissemination to peritoneal surfaces may be only superficial contamination of the parietal and visceral peritoneum that may be treatable for cure. Unfortunately, surgery may have an adverse impact on peritoneal surface dissemination. Surgical interventions may convert a superficial process into an invasive condition with a greatly reduced prognosis. This study was conducted to test this hypothesis by the use of data prospectively recorded from patients treated for peritoneal carcinomatosis concomitant with resection of the primary colon cancer or treated for carcinomatosis after disease recurrence prompted referral. METHODS: Our first group of patients had definitive treatment of carcinomatosis simultaneous with resection of the primary colon cancer. They had cytoreductive surgery including peritonectomy procedures followed by heated intraoperative intraperitoneal chemotherapy with mitomycin C plus early postoperative intraperitoneal 5-fluorouracil. The comparison group was treated with a colon resection at an outside hospital and then later referred to us with progressive disease for treatment. The major difference between the groups is the timing of the definitive treatment of carcinomatosis. These patients were also studied by use of the completeness of the cytoreduction score and the peritoneal cancer index as prognostic indicators. Survival was the end point for all the analysis. RESULTS: Of 104 patients with peritoneal carcinomatosis from colon or rectal adenocarcinoma, five patients (4.8 percent) had definitive treatment of the peritoneal surface spread of the cancer concomitant with resection of the primary lesion. Median survival for these patients has not been reached and their five-year survival rate is 100 percent. The remainder of the patients (n = 99) were referred for local and regional recurrence after their primary cancer had been removed and there was progression of carcinomatosis. Forty-four patients (42.3 percent) had a complete cytoreduction resulting in a 24-month median survival and a 30 percent five-year survival (P < 0.0001). The other 55 patients (52.9 percent) had an incomplete cytoreduction resulting in a 12-month median survival and a 0 percent five-year survival (P < 0.0001). Patients with a peritoneal cancer index of 10 or less had a 48-month median survival and a 50 percent five-year survival rate. Patients with a peritoneal cancer index between 11 and 20 had a 24-month median survival and a 20 percent five-year survival rate (P < 0.0001). Patients with a peritoneal cancer index of more than 20 had a 12-month median survival and a 0 percent five-year survival (P < 0.0001). CONCLUSIONS: In patients with peritoneal seeding occurring at the time of resection of the primary malignancy, peritonectomy procedures and perioperative intraperitoneal chemotherapy should be performed concomitantly. By use of a quantitative scoring system, the mass of cancer present in the abdomen and pelvis at the time of treatment of carcinomatosis correlated directly with survival. Aggressive treatment of patients with peritoneal carcinomatosis requires consideration in the management of colorectal cancer.     

Laparoscopic Resection for Colorectal Cancer in Japan

The first laparoscopic surgery for colorectal cancer in Japan was reported in 1992. In the early phase, many cases were indicated for early cancer. The number of operations has been increasing year by year, and now even some advanced cases undergo laparoscopic surgery. According to questionnaires administered in 2003 by the Japan Society for Endoscopic Surgery, more than half of 3,892 cases were indicated for advanced cancer. In 2004, the 60th biannual meeting of the Japanese Society for Cancer of the Colon and Rectum took up "the current status of laparoscopic resection for colorectal cancer" as one of the main topics of the meeting, and conducted a questionnaire survey of the member’s opinions to laparoscopic resection for colorectal cancer prior to the meeting. It was revealed that at least ninety institutes had already performed a laparoscopic resection for colorectal cancer. In order to evaluate the feasibility of laparoscopic resection for colorectal cancer, a randomized control study comparing laparoscopic and open resection of colorectal cancer was started in 2004. This study is scheduled to collect 818 cases. The characteristic of this study was to enroll only advanced cancer cases. The primary endpoint is the survival, while the secondary end points are disease-free survival, early postoperative course, adverse events and conversion to open surgery. As more surgeons perform laparoscopic colorectal surgery, the importance for education and credentialing has been discussed. The Japan Society for Endoscopic Surgery started a system to qualify the surgeon’s technique for endoscopic and laparoscopic surgery in 2004. One hundred and three surgeons took the examination for laparoscopic colorectal surgery in 2004, and 43 passed. Reprints are not available.