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PubMed1995

[Precancerous lesion in colorectal cancer].

Precancerous lesion in colorectal cancer was reviewed in terms of the evolution of the adenomacarcinoma sequence. K-ras codon 12 point mutation frequencies, examined in 157 adenomas, were observed in polypoid adenomas (67%) and flat adenomas (21%). Among flat adenomas, completely flat or depressed ones showed especially low mutation frequency (8%). K-ras mutation frequencies, examined in 70 invasive carcinomas, were observed in polypoid carcinomas (64%) and nonpolypoid ones (13%). From the results, it is suggested that polypoid adenomas develop into polypoid carcinomas and flat adenomas into non-polypoid carcinomas.

Adenoma↗
PubMed1996

Genetic mapping of hereditary mixed polyposis syndrome to chromosome 6q.

Hereditary mixed polyposis syndrome (HMPS) is characterized by atypical juvenile polyps, colonic adenomas, and colorectal carcinomas. HMPS appears to be inherited in an autosomal dominant manner. Genetic linkage analysis has been performed on a large family with HMPS. Data did not support linkage to the APC locus or to any of the loci for hereditary nonpolyposis colorectal cancer. Evidence that the HMPS locus lies on chromosome 6q was, however, provided by significant two-point LOD scores for linkage between HMPS and the D6S283 locus. Analysis of recombinants and multipoint linkage analysis suggested that the HMPS locus lies in a 4-cM interval containing the D6S283 locus and flanked by markers D6S468 and D6S301.

Adenoma↗
PubMed1996

[Hereditary nonpolyposis colorectal cancer].

Hereditary non polypous colon cancer (HNPCC) is inherited in a dominant fashion, and accounts for 29-39% of all colon and rectum carcinomas occurring in people under 50 years of age. We present a case of a young male with a short history of fluctuating diarrhoea and bleeding per rectum. Family records showed a high incidence of colon and rectum cancer. Coloscopy showed a colon tumour that was treated by total colectomy. To obtain the correct diagnosis a thorough family history is crucial. Having found a sick individual in a family it is now possible to identify genotype-carriers among family members.

Adult↗
PubMedDate not supplied

Risk of cancer development in the rectal remnant of patients with familial adenomatous polyposis/Gardner's syndrome.

BACKGROUND/AIMS: Current treatment for familial adenomatous polyposis usually entails total colectomy. However, the question of whether or not to remove the rectum has yet answered decisively. This paper represents an attempt to clarify the position on whether the surgeon should remove the rectum. PATIENTS AND METHODS: Twenty patients from 16 families with the established diagnosis of FAP, or Gardner's syndrome, who had been treated by total colectomy with ileorectal anastomosis, were followed up by proctoscopy for at least 5 years. The clinical features were compared between the patients with histologically verified rectal cancer and those who had been free from cancer development. RESULTS: During the observation periods ranging from 5 to 27 years (mean, 11.4 years), five rectal cancers were identified in 4 patients. These cancers included two cancers in adenomas, two nonpolypoid cancers, and one invasively ulcerating tumor. While the clinical and pathologic features at surgery and the incidence of colonic cancer in the resected specimen had not differed between the patients with rectal cancer and those without cancer, the former group of patients had more colonic polyps and they tended to have been observed over longer periods than the latter group of patients. CONCLUSION: These findings suggest that clinical features at surgery of patients with FAP are not relevant for predicting the development of rectal cancer during follow-up.

Adenomatous Polyposis Coli↗
PubMed1997

Evaluation of rectal mucosal hemodynamics in patients with liver cirrhosis using reflectance spectrophotometry.

OBJECTIVES: Portal hypertensive colonopathy is observed in patients with liver cirrhosis. To determine the correlation between rectal mucosal hemodynamics and portal hypertensive colonopathy, we observed rectal mucosal findings and measured rectal mucosal hemodynamics in patients with liver cirrhosis. METHODS: Thirty-four patients with liver cirrhosis and 16 healthy control subjects were simultaneously examined for rectal mucosal findings by colonoscopy and indices of rectal mucosal Hb concentration (RHb) and rectal mucosal oxygen saturation by reflectance spectrophotometry. Endoscopic findings in the rectal mucosa of patients with liver cirrhosis included vascular ectasias, blue veins, and varices. We investigated the relationship between rectal mucosal hemodynamics and clinical parameters of liver cirrhosis (Child-Pugh classification, the amount of indocyanine green remaining in the blood 15 min after its injection, and ascites). Patients with hepatocellular carcinoma, colonic cancer, multiple colonic polyps, or severe anemia were excluded. RESULTS: Rectal mucosal lesions were observed in 11 patients with liver cirrhosis (32.4%). In the hemodynamic studies, we found significantly increased RHb values in the cirrhosis group as compared with the control group. On the other hand, there was no significant change in rectal mucosal oxygen saturation between the two groups. A significant increase in RHb was observed in patients with rectal mucosal lesions in the cirrhosis group. RHb in the cirrhosis group correlated with grade of Child-Pugh classification. Increased RHb decreased in parallel after portal decompression by creation of a transjugular intravenous portosystemic stent shunt. CONCLUSIONS: The rectal mucosal lesions in liver cirrhosis correlate with an increase in RHb, which correlates with portal hypertension.

Ascites↗
PubMedDate not supplied

Non-lymphoid cancer after liver transplantation.

BACKGROUND/AIMS: The increasing length of survival of organ transplant recipients necessitates careful attention to the potential neoplastic complications of life-long immunosuppression, which is required for such patients. Previous studies by Penn of patients taking triple drug therapy (Cyclosporin, Azathioprine and Prednisone) for immunosuppression, or even of those taking Imuran and Cyclophosphamide, have shown a high percentage of tumor development (3117 per 2915 patients). METHODOLOGY: Three thousand three hundred and ninety-four adult patients underwent orthotopic liver transplantation (OLTx) at the University of Pittsburgh Medical Center, Transplant Institute prior to December, 1992. Of these, 1657 were examined (48.8%). All patients with hepatic or biliary cancer as the indication for OLTx were excluded; all other indications were considered. All forms of tumor development after OLTx were considered, except for lymphoprolipherative disease and hepato-biliary tumors. The immunosuppressive regimens were reviewed and patients treated with FK 506 and Cyclosporin A (CSA), as well as those switched from CSA to FK 506, were divided into different groups. RESULTS: A total of 50 patients with tumors were identified (37 males, 13 females), ranging between 34 and 69 years of age. Of these patients, 48 are still alive. In these patients, 64 tumors, classified according to the TMN classification, were discovered: 50 in males and 14 in females. Two metastases were found following discovery of the tumor. The tumors identified were as follows: basalioma 25%, squamous 20.3%, Bowen 6.2%, warts 3.1%, melanoma 6.2%, Kaposi's sarcoma 3.1%, colonic adenocarcinoma 3.1%, colonic polyps 4.6%, rectal cancer 1.5%, breast cancer 4.6%, cervical cancer 3.1%, ovarian cancer 3.1%, laryngeal cancer 3.1%, prostate cancer 1.5%, lung cancer 3.1%, gastric cancer 3.1%, and hemangioblastoma 1.5%. CONCLUSIONS: Skin cancer is the most common type of tumor discovered after liver transplantation (The transplant does not change the occurrence in lung transplants with a positive smoking history). A lower incidence of tumors was found after liver transplantation as compared to kidney transplantation. A higher incidence of tumors was found with CSA, as opposed to FK 506 immunosuppression therapy. None of the patients in this series experienced acute graft rejection necessitating re-transplantation. Chronic graft rejection was treated either with FK 506 or with OKT3, without an increase in the incidence of tumor development.

Adult↗
PubMed1997

Familial juvenile polyposis coli with APC gene mutation.

Familial juvenile polyposis has been known to have malignant potential, but their genetic relation to familial adenomatous polyposis has not been proven yet. Two young brothers with intermittent rectal bleeding revealed multiple juvenile polyposis. Their father had a history of rectal cancer with multiple colonic polyps. Four frequent exons of APC gene mutation were tested from these patients' white blood cells by polyacrylamide gel electrophoresis and sequencing. The 21-yr-old brother had a missense mutation (GAA-->GGA) at codon 1309, whereas the 18-yr-old brother showed a missense mutation (ATA-->GTA) at codon 1304 in exon 15 of APC gene. Three of four first-degree relatives were affected with familial juvenile polyposis, familial juvenile polyposis with adenomatous change, and rectal cancer with multiple polyps. The APC gene mutation of familial juvenile polyposis in this case suggests a genetic relationship with familial adenomatous polyposis.

Adenomatous Polyposis Coli↗
PubMed1998

The expression of p120ctn protein in breast cancer is independent of alpha- and beta-catenin and E-cadherin.

Several studies have reported loss or alteration of expression of E-cadherin in breast cancer and more recently changes in levels of expression of the catenins. We used immunofluorescence to examine E-cadherin, alpha-catenin, beta-catenin, and p120ctn (formerly p120CAS) expression in 91 cases of invasive ductal carcinoma. As expected, all four proteins co-localize to the junctional regions of the cells. Although nuclear localization has been described for beta-catenin in colonic polyps, no examples were found in these breast cancer cases. We found that, although alteration is common in the catenins and E-cadherin, complete loss, as exemplified by E-cadherin in lobular carcinoma (where E-cadherin is frequently mutated), is rarely seen. In contrast, the catenin-related protein p120ctn shows an expression pattern that is significantly unrelated to the other catenins (or E-cadherin), including complete loss of expression in approximately 10% of the cases. No statistically significant correlations with traditional prognostic indicators were observed with any of these proteins. We conclude 1) that expression of E-cadherin and alpha- and beta-catenin are generally retained at the membrane although frequently reduced or altered, 2) that complete loss of p120ctn expression is seen in approximately 10% of the cases, and 3) that there is a significant correlation in the expression of E-cadherin and the catenins but no correlation between these molecules and p120ctn, suggesting an absence of coordinate regulation.

Adult↗
PubMed1998

Fecal occult blood testing: clinical value and limitations.

Occult blood in the stool can be detected by chemical (guaiac), heme-porphyrin, or immunological methods. Each has advantages and disadvantages, with the guaiac slide test Hemoccult II (SmithKline Diagnostics) remaining the most widely used. Various technical factors affect its clinical performance, most notably whether the slides are rehydrated before processing; hydration increases test sensitivity for colorectal cancer but markedly decreases specificity, resulting in a large number of false-positive reactions that require invasive and expensive colonic workup. Newer immunological tests generally have high sensitivity, but poor specificity remains an important problem. In clinical screening situations, unhydrated Hemoccult has about 50% sensitivity for colorectal cancers and about 98% specificity. Only 5% to 10% of positive reactions prove due to cancer, however, so the large majority of reactive tests are false positives; this is an important weakness of occult blood screening. Slide hydration detects more tumors, but the predictive value of a positive test for cancer drops to only about 2%, which greatly diminishes the appeal of hydration. Sensitivity of occult blood tests for benign colonic polyps is poor, and most polyps found during workup of a positive reaction are actually detected by chance because of high prevalence in the general population. Controlled clinical trials have now documented that periodic occult blood screening produces a relatively small but significant mortality benefit from colorectal cancer--about 15% to 18% for biennial testing with unhydrated Hemoccult. Aggressive annual screening with hydrated Hemoccult may lower mortality by more than 30% but at a very high cost because of poor specificity and very low predictive value. Regular occult blood testing beginning at age 50 has been endorsed by many professional organizations because of the documented mortality benefit, but poor compliance, high costs, and ethical uncertainties seriously temper its justification. Whether to implement widespread occult blood screening remains a difficult societal decision.

Colorectal Neoplasms↗
PubMed1998

Stimulation of apoptosis by sulindac and piroxicam.

1.Sulindac, cis-5-fluoro-2-methyl-1-(p-methylsulphinylbenzylidene)indene-3-ace tic acid, inhibits growth of colon polyps and cancers. This effect has been attributed to inhibition of prostaglandin synthesis but more recent observations indicate that, in vitro, cells that do not have cyclo-oxygenase nor RNA for synthesis of such enzymes are affected by sulindac. Therefore the presumptive effect is probably not correct.2.It has also been found that sulindac stimulates apoptosis. It is herein postulated that in tumour cells such effects may be due to interaction of the anionic form of the drug with protons in the intermembrane space of mitochondria to disrupt the potential across the inner mitochondrial membrane and thereby initiate apoptosis. Normal cells are not affected.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1998

[Leiomyosarcoma of the prostate: report of two cases].

We herein present two cases prostatic leiomyosarcoma. The first case was in a 45-year-old man who presented at our department with the chief complaints of pain on voiding and pollakisuria on November 13, 1996. Ultrasonography and computed tomographic (CT) scan revealed a prostatic tumor. A histological examination of biopsy specimens revealed leiomyosarcoma of the prostate. Total prostatectomy and partial cystectomy were performed. No adjuvant therapy was performed. He is still alive without disease 12 months after operation. The second case was in a 63-year-old man who was admitted to our hospital for treatment of a lung tumor and colon polyp on February 28, 1997. CT scans showed a large prostatic tumor and multiple tumors in the lung, liver and bilateral kidneys. He was referred to our department for evaluation of the prostatic tumor. A transrectal needle biopsy of the prostate for histological diagnosis revealed leiomyosarcoma. No treatment was performed and he died 3 months later. In addition, 57 cases of prostatic leiomyosarcoma collected from the Japanese literature are also reviewed.

Cystectomy↗
PubMed1982

Transitional polyps of the colon.

Fourteen polps with the gross appearance of small hyperplastic (metaplastic) polyps, not exceeding five mm in diameter, were removed from the rectum and the sigmoid colon of patients during colonscopy, and from surgical specimens. At light microscopy they were seen to be composed of apparently normal mucosa. In most cases some hyperplastic (metaplastic) and adenomatous polyps were also present. HID-AB stain revealed the polyps to be composed of "transitional" mucosa containing almost exclusively sialomucins, in contrast to normal mucosa, in which sulphomucins predominate. It is suggested that these "transitional" polyps may represent a reservoir of hyperplastic (metaplastic) and adenomatous polps, the different fate depending on different environmental situations.

Colonic Neoplasms↗
PubMed1994

Fibrovascular polyp of the sigmoid colon.

A case of a fibrovascular polyp of the sigmoid colon is reported. The patient tested positively for fecal occult blood on a mass survey for colorectal cancer, and underwent colonoscopic examination which revealed a pedunculated submucosal tumor in the sigmoid colon. The tumor, about 10 mm in diameter, had a short thin stalk and was removed endoscopically; the histological diagnosis was fibrovascular polyp. This extremely rare polyp is discussed, and particular attention is focused on the unusual endoscopic features and on the appropriate management.

Aged↗
PubMed2002

Colonic cancer and polyps.

Colorectal cancer (CRC) is one of the best studied cancers. It is easily accessible and develops slowly over several years from premalignant lesions (adenomatous polyps) to invasive cancers. The key molecular events in this sequence have been characterized. Different screening strategies have proven to be effective in lowering both the mortality and the incidence of CRC. Nevertheless, CRC is still the second leading cause of cancer-related deaths for both men and women in the USA and other Western countries. An estimated 130 000 new cases and more than 50 000 deaths have been diagnosed in the USA in 2000. Surgical resection remains the only curative treatment, and the likelihood of cure is greater when the disease is detected at an early stage. Hereditary non-polyposis colorectal cancer (HNPCC) and the different polyposis syndromes such as familial adenomatous polyposis (FAP) or Peutz-Jeghers disease are rare causes of CRC but have been a major focus of research in past years, helping with the understanding of the molecular events in carcinogenesis. This review summarizes our current knowledge of the pathogenesis and management of colorectal polyps and polyposis syndromes as well as sporadic CRC.

Adenomatous Polyposis Coli↗