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Application of technetium-99m-labeled human serum albumin scan to assist surgical treatment of protein-losing enteropathy in Cronkhite-Canada syndrome: report of a case.

Cronkhite-Canada syndrome is a rare form of nonhereditary gastrointestinal polyposis associated with ectodermal change and protein-losing enteropathy. Here we report a 63-year-old male presenting with diffuse gastrointestinal polyposis, onychodystrophy, cutaneous pigmentation, alopecia, diarrhea, hypoalbuminemia and lower leg edema. Technetium-99m-labeled human serum albumin scan confirmed the patient to have protein-losing enteropathy, which originated from the transverse and descending colon. Subtotal colectomy was performed. Albumin level and ectodermal change were gradually improved during three years of outpatient clinic follow-up. Based on our finding, Technetium-99m-labeled human serum albumin scintigraphy is helpful to localize the protein-losing origins and surgery is an effective treatment for Cronkhite-Canada syndrome with protein-losing enteropathy.

Colectomy↗

Genetics of colorectal cancer.

Colorectal cancer (CRC) is the second leading cause of cancer-related mortality in the United States. As such, it assumes a significant role in both health policy decision-making and scientific research. CRC has been a model for investigating the molecular genetics of cancer development and progression; this is in part due to the easily detectable, sequential transition of cells from normal colonic epithelium to adenoma and then to adenocarcinoma. In addition, familial syndromes that predispose to CRC, such as familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer (HNPCC), have significantly contributed to our understanding of the genetic mechanisms underlying CRC formation. It is now well recognized that hereditary CRC syndromes are due to germline mutations of genes that function as tumor suppressors or, less frequently, oncogenes. Accumulation of subsequent mutations in other genes with related functions results in the stepwise progression to carcinoma. It is important to note that somatic changes in similar genes are involved in the formation of sporadic CRC. The identification of these important CRC-related genes may help facilitate the early diagnosis, prevention, and treatment of CRC. This article reviews the various familial CRC syndromes along with their genetic etiology, as well as discusses the principle of genetic testing for these conditions.

Colorectal Neoplasms↗

MUTYH-associated polyposis--from defect in base excision repair to clinical genetic testing.

Established predisposition genes account for only a small proportion of familial colorectal cancer. Recently, it has been shown that germline mutations in MUTYH predispose to MUTYH-associated polyposis (MAP), an autosomal recessive disorder characterised by multiple colorectal adenomas and carcinomas. MUTYH functions as a base excision repair DNA glycosylase that excises adenines misincorporated opposite 8-oxo-7,8-dihydro-2'-deoxyguanosine, one of the most stable products of oxidative DNA damage. It is the failure to correct this mispair that is thought to give rise to the characteristic signature of G:C-->T:A mutations found in MAP-associated tumours. Here, we review the germline mutation spectrum at the MUTYH locus (comprising 30 truncating and 55 missense/inframe insertion/deletion variants) and the molecular mechanism and biochemical defect(s) underlying this disorder. We also discuss the application of molecular genetic analysis of MUTYH in clinical practice.

Adenoma↗

Forced expression of the tumor suppressor adenomatosis polyposis coli protein induces disordered cell migration in the intestinal epithelium.

Mutations of the human adenomatosis polyposis coli (APC) gene are associated with the development of familial as well as sporadic intestinal neoplasia. To examine the in vivo function of APC, 129/Sv embryonic stem (ES) cells were transfected with DNA encoding the wild-type human protein under the control of a promoter that is active in all four of the small intestine's principal epithelial lineages during their migration-associated differentiation. ES-APC cells were then introduced into C57BL/6-ROSA26 blastocysts. Analyses of adult B6-ROSA26<-->129/Sv-APC chimeric mice revealed that forced expression of APC results in markedly disordered cell migration. When compared with the effects of forced expression of E-cadherin, the data suggest that APC-catenin and E-cadherin-catenin complexes have opposing effects on intestinal epithelial cell movement/adhesiveness; augmentation of E-cadherin-beta-catenin complexes produces a highly ordered, "adhesive" migration, whereas augmentation of APC-beta-catenin complexes produces a disordered, nonadhesive migratory phenotype. We propose that APC mutations may promote tumorigenesis by increasing the relative activity of cadherin-catenin complexes, resulting in enhanced adhesiveness and functional anchorage of initiated cells within the intestinal crypt. Our studies also indicate that chimeric mice generated from B6-ROSA26 blastocysts and genetically manipulated ES cells should be useful for auditing gene function in the gastrointestinal tract and in other tissues.

Adenomatous Polyposis Coli Protein↗

Prospective comparison of laparoscopic left hemicolectomy for colon cancer with laparoscopic left hemicolectomy for benign colorectal disease.

BACKGROUND: Short-term outcome and anorectal function results after laparoscopic hemicolectomy for colon cancer were compared with results after laparoscopic hemicolectomy for benign diseases. METHODS: A total of 108 patients who underwent laparoscopic left colectomy (60 for colon cancer, 48 for diverticulitis or polyposis) were enrolled in the study. Left hemicolectomy in patients affected by cancer was performed by high ligation of the inferior mesenteric artery. A questionnaire concerning anorectal function was mailed to patients 6 months after surgery. RESULTS: Complications were more frequent in the cancer group than in the benign disease group: overall morbidity rate (29.6% versus 8.7%; P = 0.009), diarrhea during the first 6 postoperative months (58.7% versus 34.1%; P = 0.022), and anorectal function problems (fecal incontinence and/or the inability to discriminate between gas and stool, and/or urgency, and/or tenesmus) (65.2% versus 31.7%; P = 0.002). DISCUSSION: The level of ligation of the lower mesenteric artery and damage at the lower mesenteric ganglion could explain the poorer anorectal function outcome in the colon cancer group.

Aged↗

Cronkhite-Canada syndrome containing colon cancer and serrated adenoma lesions.

We describe a case of Cronkhite-Canada syndrome associated with sigmoid colon cancer, and provide a literature review. A 77-year-old man was diagnosed with sigmoid colon cancer after presenting with hypoproteinemia, nail atrophy, loss of scalp hair, hyperpigmentation, and gastrointestinal polyposis. The findings were consistent with Cronkhite-Canada syndrome. The colon polyps were histologically serrated adenomas, whose crypts showed a saw-toothed growth pattern with dysplasia, or tubular adenoma. Cronkhite-Canada syndrome associated with colon cancer has been reported in 31 cases. The availability of histologic material permitted reexamination of 25 of these cases. Serrated adenoma of the polypoid lesions was retrospectively found in 10 (40%) of the 25 cases. By comparison, the incidence of serrated adenomas has been estimated to occur in about 1% of all general polyps. Taken together, it is suggested that Cronkhite-Canada syndrome associated with colorectal cancer frequently has polyps containing serrated adenoma lesions. In the case described here, microsatellite instability and overexpression of the p53 protein were found in the cancer lesion and serrated adenoma lesions, and none of the lesions showed a loss of heterozygosity of various genes or K-RAS mutations. Thus, genetic alterations between the serrated adenoma and the colorectal cancer was correlated in this case. These findings suggested the possibility of a serrated adenoma-carcinoma sequence in this case of Cronkhite-Canada syndrome.

Adenoma↗

BRAF mutation is associated with DNA methylation in serrated polyps and cancers of the colorectum.

BACKGROUND AND AIMS: Mutations in BRAF have been linked with colorectal cancers (CRC) showing high level microsatellite instability (MSI-H). However, the distribution of BRAF mutations in MSI-H cancers remains to be clarified with respect to precursor lesions and the CpG island methylator phenotype (CIMP). METHODS: Forty three hyperplastic polyps (HP), nine mixed polyps (MP), five serrated adenomas (SA), 28 conventional adenomas (AD), 18 hereditary non-polyposis colorectal cancers (HNPCC), and 127 sporadic CRC (46 MSI-H and 81 non-MSI-H) were collected from patients undergoing colectomy for either CRC or hyperplastic polyposis. Twenty five of 57 serrated lesions were derived from four patients with hyperplastic polyposis. HP were further subdivided according to recently documented morphological criteria into 27 classical HP and 16 variant lesions described as "sessile serrated adenoma" (SSA). All tumours were screened for BRAF activating mutations. RESULTS: The BRAF mutation was more frequent in SSA (75%) and MP (89%) than in classical HP (19%), SA (20%), and AD (0%) (p<0.0001), and also in sporadic MSI-H cancers (76%) compared with HNPCC (0%) and sporadic non-MSI-H cancers (9%) (p<0.0001). The BRAF mutation was identified more often in CIMP-high serrated polyps (72%) and CIMP-high CRC (77%) than in CIMP-low (30%) and CIMP-negative (13%) polyps (p = 0.002) as well as CIMP-low (18%) and CIMP-negative (0%) CRC (p<0.0001). CONCLUSIONS: The BRAF mutation was frequently seen in SSA and in sporadic MSI-H CRC, both of which were associated with DNA methylation. Sporadic MSI-H cancers may originate in SSA and not adenomas, and BRAF mutation and DNA methylation are early events in this "serrated" pathway.

Adenoma↗

A case of Cronkhite-Canada syndrome with vestibular disturbances.

A 66-year-old Japanese man with Cronkhite-Canada syndrome (CCS) presented with complaints of long-lasting dysequilibrium. On neuro-otological examination, he showed gaze-evoked nystagmus at the rightward and leftward gaze, and saccadic pursuit. On the caloric test, he showed no response in either side, and on the head-impulse test he showed bilateral loss of vestibule-ocular reflexes around the yaw axis, while he had bilateral normal responses on the vestibular-evoked myogenic potential testing. Neuro-otological findings suggested that he had lesions in the peripheral vestibular system as well as the central nervous system. Neurological disorders such as sensory neuropathy have been reported in patients with CCS. This patient's balance problems could be due to CCS itself.

Aged↗

Upper intestinal surveillance in familial adenomatous polyposis.

Our understanding of the natural history of upper gastrointestinal (GI) involvement in familial adenomatous polyposis (FAP) is still evolving, although we know that the main cause of death after colectomy in FAP is upper GI malignancy, affecting 5% of patients. The aim of duodenal surveillance is to target high risk individuals and identify cancers early. We have screened 200 patients prospectively and have observed that duodenal polyposis progresses slowly, but there are some young people who have severe disease who merit close observation. We pay particular attention to endoscopic technique and histological detail, and use a duodenal staging system. Patients are offered randomisation to studies of chemopreventive agents, and those with advanced disease are considered for surgery. Successful management is inhibited by our deficient knowledge of the natural history of upper gastrointestinal polyposis, and by our inability to identify high risk individuals with histological markers rather than because of any technological deficiencies in endoscopic equipment.

Adenomatous Polyposis Coli↗

Localization of a susceptibility locus for Peutz-Jeghers syndrome to 19p using comparative genomic hybridization and targeted linkage analysis.

Many human cancer susceptibility genes have been successfully mapped by genetic linkage studies. One that has so far eluded researchers is that for Peutz-Jeghers (P-J) syndrome, a condition characterized by intestinal hamartomatous polyposis and melanin spots of the lips, buccal mucosa and digits. A dramatically elevated risk of malignancy has also been documented. Gastrointestinal tumours as well as cancers of the breast, ovary, testis and uterine cervix appear to be overrepresented in families with this syndrome. The nature of hamartomatous polyps is equivicol. Hamartomas are usually considered histologically benign, but in the case of Peutz-Jeghers patients, there are reports of adenomatous and malignant changes in the polyps, and the possibility of a hamartoma-carcinoma sequence has been discussed. A search for a putative tumour suppressor locus was made using comparative genomic hybridization (CGH) of Peutz-Jeghers polyps, combined with loss of heterozygosity (LOH) study. Genetic linkage analysis in 12 families using markers from a deletion site demonstrated the presence of a high-penetrance locus in distal 19p with a multipoint lod score of 7.00 at marker D19S886 without evidence of genetic heterogeneity. The study demonstrates the power of CGH combined with LOH analysis in identifying putative tumour suppressor loci, and provides molecular evidence of malignant potential in hamartomas.

Adenocarcinoma↗

Treatment of facial lentigines in Peutz-Jeghers syndrome with an intense pulsed light source.

BACKGROUND: Peutz-Jeghers syndrome is a hereditary condition characterized by distinctive mucocutaneous lentigines and intestinal hamartomatous polyposis. The cutaneous lesions may be cosmetically disfiguring and frequently present a therapeutic challenge. OBJECTIVE: To determine if intense pulsed light (IPL) is effective in treating facial lentigines in Peutz-Jeghers syndrome. METHODS: The IPL, utilizing a 590 nm cutoff filter, was used to treat facial lentigines in a 10-year-old girl with Peutz-Jeghers syndrome. RESULTS: A series of 12 treatment sessions, each to different facial regions, resulted in complete clearance of lentigines in the treated areas. Most of the lentigines resolved after a single treatment, with a few areas requiring a second treatment. CONCLUSION: In this case, treatment with IPL resulted in dramatic improvement of cosmetically disfiguring lentigines. To our knowledge, this is the first report of using IPL in Peutz-Jeghers syndrome.

Child↗