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Kenjiro Kotake

Publications and source records attributed to Kenjiro Kotake.

12 recordsLinked to original sources
PubMed2007

Prognosis and risk factors of metastasis in colorectal carcinoids: results of a nationwide registry over 15 years.

BACKGROUND: Colorectal carcinoids are often described as low-grade malignant. However, no study has compared the survival between patients with colorectal carcinoids and those with carcinomas, in a large series. In addition, no global consensus has been established on the crucial determinants of metastasis in colorectal carcinoids. AIM: To determine the predictive factors for metastasis in colorectal carcinoids and clarify their prognosis compared with adenocarcinomas. METHODS: Data of all patients diagnosed as having colorectal carcinoids were extracted from a large nationwide database of colorectal tumours, the Multi-Institutional Registry of Large-Bowel Cancer in Japan, for the period from 1984 to 1998. Risk factors for lymph node (LN) metastases and distant metastases were analysed among those who were undergoing surgery, by univariate and multivariate analysis. Cancer-specific survival was also compared between patients with colorectal carcinoids and those with adenocarcinomas registered in the same period. RESULTS: Among the 90 057 cases of colorectal tumours that were diagnosed, a total of 345 cases of carcinoids were identified, including 247 colorectal carcinoids of those undergoing surgery. Risk factors for LN metastasis were tumour size >/=11 mm and lymphatic invasion, whereas those for distant metastasis were tumour size >/=21 mm and venous invasion. Colorectal carcinoids without these risk factors exhibited no LN metastasis or distant metastasis. Cancer-specific survival of patients with colorectal carcinoids without metastasis was better than that of those with adenocarcinomas. However, the survival was similar between carcinoids and adenocarcinomas if the tumours had LN metastasis or distant metastasis. CONCLUSIONS: The presence of metastasis in colorectal carcinoids could lead to survival that is as poor as in adenocarcinomas. Tumours </=10 mm and without lymphatic invasion could be curatively treated by local resection, but others would need radical LN dissection.

Adenocarcinoma↗
PubMed2006

Characteristics of recurrence and surveillance tools after curative resection for colorectal cancer: a multicenter study.

BACKGROUND: The aim of this study was to clarify the characteristics of recurrence and the effectiveness of surveillance tools after curative resection for colorectal cancer. METHODS: We enrolled 5230 consecutive patients (stage I, 1367; stage II, 1912; stage III, 1951) who underwent curative resection at 14 hospitals from 1991 to 1996. All patients were followed up intensively, and their outcomes were investigated retrospectively. RESULTS: Of the 5230 patients, 906 developed recurrence. The recurrence rates of stage I, II, and III cancers were 3.7%, 13.3%, and 30.8%, respectively (P < .0001). The curves of the cumulative appearance rate of recurrence in stage II and III patients showed a rapid increase for the first 3 years. Recurrence after 5 years was less than 1% in each stage. Clinical visits combined with measurements of tumor markers detected the majority of recurrences except in the case of lung metastasis. In contrast, 43.4% of hepatic recurrences were detected by liver imaging, and 48.4% of pulmonary recurrences were noted by chest x-ray. The 5-year survival rates after primary colorectal surgery in patients who underwent resection for recurrence were better than in those without resection: 55% vs 11% in hepatic recurrence, 68% vs 13% in pulmonary recurrence, and 48% vs 22% in local recurrence (all P < .001). CONCLUSION: It is useful to take these characteristics of recurrence into account in the management of patients after curative resection for colorectal cancer and in the setting of clinical trial for follow-up after curative resection for colorectal cancer.

Aged↗
PubMed2005

A multicenter randomized study comparing 5-fluorouracil continuous infusion (ci) plus 1-hexylcarbamoyl-5-fluorouracil and 5-FU ci alone in colorectal cancer.

To verify the effectiveness of oral 1-hexylcarbamoyl-5-fluorouracil (HCFU) in improving the surgical cure rate in advanced colorectal cancer, a multicenter randomized comparative study was conducted. A total of 429 patients who had had curative resection for stage II and III colorectal cancer were randomly assigned to a study group receiving a 14-day course of 5-FU continuous infusion (320 mg/m2/day) followed by oral HCFU for a year (300 mg/day), or to the control group receiving a 14-day course of 5-FU continuous infusion alone. In terms of background factors, no significant differences were found between the 214 patients in the study group and the 215 in the control group. Adverse reactions during the treatment were more frequently seen in the study group. But with few exceptions, the toxicities were mild and the compliance was acceptable. The 5-year overall survival rate of the study group was similar to that of the control group. The 5-year disease-free survival rate of the study group was better than that of the control group in the patients with colon cancer (hazard ratio=1.87; 95% confidence interval 1.03-3.38; p=0.037). However, this benefit was not seen in the patients with rectal cancer. A significant improvement in the disease-free survival rate was demonstrated through the addition of HCFU to 5-FU continuous infusion for the patients with colon cancer. The usefulness of oral fluoropyrimidine as an adjuvant for curative surgery for colon cancer was further warranted.

Adult↗
PubMed2004

Dysfunction of p53 pathway in human colorectal cancer: analysis of p53 gene mutation and the expression of the p53-associated factors p14ARF, p33ING1, p21WAF1 and MDM2.

Mutations of p53 tumor suppressor gene increase with tumor progression in colorectal cancers. In this study, we examined the expressions of p33ING1, p14ARF, MDM2 and p21WAF1 mRNA in 25 advanced colorectal cancers by quantitative RT-PCR method, and compared the expression levels of p33ING1, p14ARF, p21WAF1 and MDM2 in relation to p53 status in the tumors. Fifteen of 25 colorectal cancers (60%) showed abnormal accumulation of p53 protein in the nucleus, and the remaining 10 colorectal cancers (40%) were negative for p53 immunostaining. We found a G --> T transition (nonsense mutation) at the first nucleotide of codon 298 (exon 8) in one p53-negative case, and a frame shift mutation on exon 7 in another p53-negative case. In remaining eight p53-negative cases, there was no mutation in the entire open reading frame of p53 cDNA. Interestingly, in eight cases with p53 wild-type gene, 6 cases (75%) showed a marked down-regulation of p14ARF mRNA, and three cases (37.5%) over-expressed MDM2 mRNA. Only one case with wild-type p53 gene showed normal level expression of p53 regulatory-factors (p33ING1, p14ARF, and MDM2). Thus, p53 tumor suppressor pathway was disrupted in 24 of 25 colorectal cancers (96%).

Aged↗
PubMed2003

Methylation profile of the MLH1 promoter region and their relationship to colorectal carcinogenesis.

Methylation of the MLH1 promoter region has been suggested to be a principal mechanism of gene inactivation in sporadic microsatellite instability (MSI)-positive colorectal carcinoma. Recently, we have shown a novel methylation profile of the MLH1 promoter region (i.e., full, partial, and no methylation), among which full methylation was strongly associated with MSI. In this study, to confirm whether methylation requires the involvement of both alleles, we studied the MLH1 promoter region concerning the methylation profile and allelic loss. Furthermore, we studied correlations of methylation profiles with genetic alternations such as loss of heterozygosity (LOH) of the TP53 locus and KRAS mutation. Eighty-eight tumors were classified as full (n = 14), partial (n = 26), and no methylation (n = 48). Full methylation was observed in 78% (14/18) of high-frequency MSI, in which all CpG sites in the promoter region were methylated. Full methylation differed significantly from partial methylation regarding absence of TP53 LOH (0/12) and KRAS mutation (0/14). In cases with full methylation, we could show biallelic methylation by use of a single-base nucleotide polymorphism in the promoter. However, this did not accompany LOH of the MLH1 locus. In contrast, there were no significant differences in molecular features between partial and no methylation, except for low frequencies of LOH of the MLH1 locus (P = 0.02). In conclusion, biallelic extensive methylation of the MLH1 promoter region plays a significant role in gene inactivation and is independent of KRAS mutation and TP53 LOH.

Adaptor Proteins, Signal Transducing↗
PubMed2003

Changes in colorectal cancer during a 20-year period: an extended report from the multi-institutional registry of large bowel cancer, Japan.

PURPOSE: This study was designed to examine trends of colorectal cancer in relation to age, gender, site, and survival during the past 20 years. METHODS: The multi-institutional registry of the Japanese Society for Cancer of the Colon and Rectum offered 87,695 surgical cases with invasive adenocarcinoma during 1978 to 1997 for analysis. We calculated survival rates and used the Cox's proportional hazard model for cases during 1978 to 1994. RESULTS: The number of cases showed a 2.5-fold increase with consistent male predominance confined to the distal colon and the rectum. Colon cancer in the last five-year period was more likely right-sided for females (odds ratio, 1.26; 95 percent confidence interval, 1.16-1.38) and males (odds ratio, 1.16; 95 percent confidence interval, 1.06-1.25) compared with the first period. Cancers in younger patients were more likely at Stage III to IV in the late 1990s if the cancers were in the distal colon, the rectum (for both genders), or the proximal colon (for females). Survival was improved except for cases with proximal colon cancer of Stage IV. In the multivariate analysis, hazard ratios for death in the postoperative five years were 0.77, 0.59, and 0.66 for proximal colon, distal colon, and rectal cancers, respectively, in the last period as compared with those in the first period [corrected]. Reduced hazard ratio for females was the largest for proximal colon cancer with Stage I to II. CONCLUSION: Although surgical outcome was largely improved, delayed presentation or diagnosis in younger patients remained a problem. Preferential localization in the proximal colon and survival benefit for females should be investigated.

Adenocarcinoma↗
PubMed2002

[Neo-adjuvant chemotherapy with carmofur for colorectal cancer--a multi-institutional randomized controlled study].

The efficacy and safety of preoperative chemotherapy with carmofur (HCFU) for colorectal cancer were evaluated in a randomized controlled study involving 63 institutes in the Kanto area. Patients aged 75 or younger with Dukes' B or C colorectal cancer were eligible if curative surgery was expected. In the end, 326 were eligible from 405 consecutive colorectal cancer patients. Patients in both the control (n = 162) and the new treatment group (n = 164) were given intravenous mitomycin C (MMC) 6 mg/m2 on day 0 and 7 after surgery and HCFU 300 mg/day orally from day 14 for a year. Patients in the new treatment group were also given oral HCFU for 14 days or more prior to surgery. All 326 patients were followed for 5 years or longer. Five-year overall and disease-free survival rates were not significantly different between the two groups (75.4% and 71.6% for the control, and 71.8% and 71.5% for the study group, respectively). In the subset analysis, neither cancer site nor nodal status affected the differences in overall- and disease-free survival rates between the groups. The present findings show no additional efficacy of preoperative chemotherapy with HCFU in survival from advanced colorectal cancer. Further investigations in terms of patient selection, treatment regimen, combined use of radiotherapy, and other factors would be required to determine the significance of preoperative chemotherapy against advanced colorectal cancer.

Aged↗
PubMed2002

[Hepatic metastases from alpha-fetoprotein producing colorectal cancer that responded remarkably to transcatheter arterial chemo-embolization].

Although alpha-fetoprotein (AFP)-producing colorectal cancer is extremely rare, its potential for liver metastasis is high and the prognosis of the patient is very poor. We report a case of metastatic liver tumor from an AFP producing sigmoid colon cancer that was successfully treated with transcatheter arterial chemo-embolization (TACE). A 48-year-old female was admitted to our hospital complaining of anal bleeding, and was diagnosed as harboring a type 2 advanced tumor with two metastatic lesions in the lateral segment of the liver. Serum AFP measured 948.2 ng/ml before surgery. We performed sigmoidectomy and lateral segmentectomy of the liver. Pathological examination revealed moderately differentiated adenocarcinoma both in the primary and the metastatic lesions, and AFP-stain positive nests were seen on immunohistochemical staining. The serum AFP value returned to normal soon after the surgery. Five months later, a recurrent lesion was discovered in the right lobe of liver, and it was surgically removed. Another 4 months later, multiple liver metastases were recognized and the patient's serum AFP level was found to be 593.3 ng/ml. For the re-recurrent hepatic lesions of 5.5 cm in diameter, she underwent two courses of TACE using Lipiodol and epirubicin hydrochloride. Following the treatment, the tumor shrank rapidly and almost disappeared. The patient has been in good health for 24 months since the last TACE, and the serum AFP level has been within the normal range.

Antibiotics, Antineoplastic↗
PubMed1999

Long-term postoperative survival of a gastric cancer patient with numerous para-aortic lymph node metastases.

A56-year-old man with advanced gastric cancer was referred to our hospital. Preoperative abdominal computed tomography revealed numerous enlarged lymph nodes, including the lymph nodes of the paraaortic region. The patient underwent total gastralectomy, splenectomy, left-adrenalectomy and resection of the body and tail of the pancreas by Appleby's method, along with paraaortic lymph node dissection. Microscopic examination revealed that the tumor was a solid type, poorly differentiated adenocarcinoma, which displayed invasion of the serosal surface. There were apparently many lymph node metastases. We identified 31 cancer-positive paraaortic nodes, while the total number of lymph node metastases was 81. It was not possible to administer sufficient postoperative adjuvant chemotherapy, as the patient experienced postoperative complications, including pancreatic fistula and watery diarrhea. Despite the lack of sufficient chemotherapy, the patient has subsequently remained disease-free for 9 years and 3 months, and continues to visit our hospital as an outpatient. In conclusion, we wish to emphasize the need for a critical application of paraaortic lymph node dissection as one modality of multidisciplinary treatment in patients with advanced gastric cancer in whom paraaortic lymph node metastasis is strongly suspected preoperatively.

Journal Article↗
PubMedDate not supplied

D2-lymphadenectomy improves the survival of patients with peritoneal cytology-positive gastric cancer.

BACKGROUND: According to the current Japanese Classification of Gastric Cancer, patients with peritoneal cytology-positive (CY1) gastric cancer are classified as stage IV and the curative potential of resection for these patients is regarded as non-curative. MATERIALS AND METHODS: We compared the clinical outcome of CY1 patients (n=55) with those of patients with other non-curative factors (n=87), to clarify the optimal surgical strategy for CY1 patients. RESULTS: The 5-year survival rate of CY1 patients was 10.8%, which was significantly better than that observed in the patients with the other non-curative factors. Among CY1 cases, survival outcome of the patients with lymph node metastasis limited to within group 2 was significantly better than the patients with group 3 lymph node metastasis. CONCLUSION: These results suggested that gastrectomy combined with extended lymphadenectomy should be recommended for patients with gastric cancer who have positive peritoneal cytology as the only non-curative factor.

Adult↗