抑癌基因p16在家族性结肠息肉病与结肠息肉中的表达

目的　探讨p16蛋白在结肠家族性息肉病及结肠息肉中的表达和意义。方法　采用LSAB免疫组织化学染色法 ,检测 48例结肠家族性息肉病及 12例结肠息肉组织中p16蛋白的表达。结果　结肠家族性息肉病中p16蛋白阳性率 5 0 % (2 4/48)。结肠息肉组p16蛋白阳性率 91 7% (11/12 )。两组息肉p16蛋白阳性率差异有显著意义 (P <0 0 1)。结论　结肠家族性息肉病的发生可能与p16蛋白基因改变有关。     

Gynecological malignancies, brain tumors, and familial adenomatous polyposis.

The syndrome of familial adenomatous polyposis has a wide spectrum of clinical manifestations including adenomatous polyps of the colon and small bowel, adenocarcinoma of ampulla of Vater, tumors of the central nervous system, bone lesions, and various soft tissue tumors. The one common denominator is colonic polyposis. It is not known whether this phenotypic heterogeneity is due to various genotypes, or if the entire clinical spectrum is due to one genetic defect. We are reporting the association of gynecologic malignancies with familial adenomatous polyposis as an additional variant of this disease. This report is on two sisters from a family with familial polyposis coli who developed adenomatous polyposis of the colon, central nervous system tumors, and cancers of the ovary and uterus. The gynecological malignancies add another variant to this clinical syndrome.     

Juvenile nasopharyngeal angiofibroma: no evidence for inheritance or association with familial adenomatous polyposis

Juvenile nasopharyngeal angiofibromas (JNAs) are rare tumors with prominent vascularity and locally destructive growth. The pathogenesis of JNA is largely unknown. A causal association between JNA and familial adenomatous polyposis has been suggested. Twenty-one patients diagnosed with juvenile angiofibroma filled out a detailed patient questionnaire. No patients reported any relatives with nasopharyngeal angiofibroma or familial adenomatous polyposis. No significant regional clustering suggestive for founder effect could be identified. We believe that if there were a strong genetic predisposition or association with familial adenomatous polyposis, it should have been seen in this patient sample.     

Free urinary amino acid excretion in patients with familial polyposis of the colon

The free urinary amino acids excretion per 24 hr of the neutral and acidic amino acids did not reveal any diagnostic abnormality in five patients with familial polyposis of the colon with or without associated desmoid tumors and osteomas. One patient with Klinefelter's syndrome and familial polyposis had a urinary acid excretion pattern indistinguishable from his brother, who had familial polyposis and normal chromosomes. It is suggested that patients with familial polyposis deserve intensive biochemical study as this represents a prototype hereditary malignant disease.     

FAP, gastric cancer, and genetic counseling featuring children and young adults: a family study and review

Familial adenomatous polyposis is a highly complex and multifaceted colorectal cancer prone disorder which is often significantly confounded by extracolonic cancers inclusive of gastric cancer, a significant problem in the Orient. Gastric cancer in familial adenomatous polyposis is heavily influenced by fundic gland polyps which are often so voluminous as to defy effective endoscopic surveillance. This study involves more than two decades of investigation of an attenuated familial adenomatous polyposis family where gastric cancer posed an early diagnostic problem because it was obscured by multiple fundic gland polyps. Fundic gland polyps are common in familial adenomatous polyposis and attenuated familial adenomatous polyposis and, if voluminous, may interfere with effective endoscopic gastric cancer surveillance. This family is believed to be the first of its type reported with focus upon education and genetic counseling in the setting of a family information service. Cancer control in familial adenomatous polyposis may be partially resolved through use of familial colorectal cancer registries, with greater attention to family history and its interpretation, genetic counseling, and clinical translation for diagnosis and management.     

Current status of familial gastrointestinal polyposis syndromes

Because of the rarity of familial gastrointestinal cancer-predisposing syndromes, their exploration in literature is not extensive. In this review, an update of the clinicopathological and molecular criteria of gastrointestinal familial polyposis syndromes with potential malignant transformation is performed. In addition, a guide for screening and surveillance was synthesized and a distribution of gene mutations according to the specific syndromes and geographic distribution was included. The following inherited polyposes syndromes were analyzed: familial adenomatous polyposis, the hamartomatous familial polyposes (Juvenile polyposis, Peutz-Jeghers syndrome, Cowden syndrome, Bannayan-Riley-Ruvalcaba syndrome, hereditary mixed polyposis syndrome, Gorlin syndrome, Birt-Hogg-Dube syndrome, neurofibromatosis type I and multiple endocrine neoplasia syndrome 2B), Li-Fraumeni syndrome, and MUTYH-associated adenomatous polyposis. For proper medical care, subspecialization of gastroenterologists, pathologists, and genticists in the field of familial diseases should be introduced in the medical curriculum.     

Investigations on the significance of the adenoma-carcinoma sequence in the small bowel

In view of the rarity of small-bowel epithelial neoplasms as compared with the case for the large bowel, evidence for an adenoma-carcinoma sequence in the small bowel was studied based on a search for data in the medical literature for the years 1927 through 1986. Sufficiently defined data were found for comparison of 185 benign adenomas, 76 adenoma-with-carcinomas, and 1333 carcinomas in patients without familial polyposis disease and for 63, five, and 30, respectively, in patients with disease. For patients without polyposis, it was found that (1) 29.8% of all small-bowel adenomas (33.6% if those at Vater's ampulla are excluded) showed malignancy; (2) the mean and median ages were lower for benign adenoma than for adenoma-with-carcinoma and carcinoma, although the ratios by sex were the same; (3) there is a nearly identical spatial distribution of the three types of epithelial neoplasms within the small bowel; and (4) both the frequency of finding adenomatous residues existing in continuity with carcinoma and the life history of the adenoma-carcinoma sequence are similar in the small bowel as in the large. In comparing these results with those from patients with familial polyposis disease, it was particularly noted that (1) the only difference was that adenomas in familial polyposis occurred earlier and multiply, and (2) the spatial distributions of adenomas and carcinomas for both cases were closely similar. It is therefore postulated that the adenoma-carcinoma sequence is as significant in the small bowels as in the large. A hypothesis regarding the relationship of epithelial neoplasms in people with and without familial polyposis disease is suggested.     

The genetic basis of colonic adenomatous polyposis syndromes

Colorectal cancer (CRC) is one of the most common forms of cancer worldwide and familial adenomatous polyposis (FAP) accounts for approximately 1% of all CRCs. Adenomatous polyposis syndromes can be divided into; familial adenomatous polyposis (FAP) – classic FAP and attenuated familial adenomatous polyposis (AFAP), MUTYH-associated polyposis (MAP), NTHL1-associated polyposis (NAP) and polymerase proofreading-associated polyposis (PPAP). The polyposis syndromes genetics and clinical manifestation of disease varies and cases with clinical diagnosis of FAP might molecularly show a different diagnosis.This review examines different aspects of the adenomatous polyposis syndromes genetics and clinical manifestation of disease; in addition the genotype-phenotype and modifier alleles of FAP will be discussed. New technology has made it possible to diagnose some of the APC mutation negative patients into their respective syndromes. There still remain many molecularly undiagnosed adenomatous polyposis patients indicating that there remain causative genes to be discovered and with today’s technology these are expected to be identified in the near future. The knowledge about the role of modifier alleles in FAP will contribute to improved pre-symptomatic diagnosis and treatment.New novel mutations will continually be discovered in genes already associated with disease and new genes will be discovered that are associated with adenomatous polyposis. The search for modifier alleles in FAP should be made a priority.     

Turcot's syndrome: Case report and review of the classification

Summary We report a case of association of a brain tumor with multiple colorectal polyposis and offer an analysis of the relevant literature with a view to revising the classification of the syndrome in relation to familial multiple polyposis and Gardner's syndrome. Differences emerged, depending on the brain tumor type, which suggests that this association may be classified as two distinct syndromes.     

Genetic testing by cancer site: colon (polyposis syndromes)

ABSTRACT: Hereditary colonic polyposis conditions are all characterized by high rates of cancer, but they have diverse phenotypes, genetic heterogeneity, and assorted inheritance patterns. The most well known of these conditions include familial adenomatous polyposis, attenuated familial adenomatous polyposis, MUTYH (MutY human homolog)-associated polyposis, Peutz-Jeghers syndrome, juvenile polyposis syndrome, and Cowden syndrome. Early recognition of these conditions is not only vital for management in affected individuals, but also for prevention and early detection in at-risk relatives. Reviewed here are the genetic testing strategies for colonic polyposis, as well as an overview of characteristic features and management considerations for these syndromes.     

Giant desmoid tumor of the abdominal wall associated with familial adenomatous polyposis

In this paper a case of vast desmoid tumor of the abdominal wall associated with familial adenomatous polyposis is reported. Desmoid tumors represent a particular type of fibrous neoplasms with a higher prevalence in females. They are extremely rare in the sporadic form, while they are found in about 10% of patients affected by familial adenomatous polyposis. Despite their benign histology and the absence of metastatic potential, they can be considered as fibrosarcomas with a low level of malignancy because of their locally invasive nature. The treatment of choice is surgical excision, as wide as possible, aimed at preventing recurrences, which are frequent in this tumor type. The usefulness of complementary therapies such as radiotherapy, hormone or chemotherapy, is not entirely clear.     

Heterogeneity in the response of familial polyposis epithelial cells and adenomas to increasing levels of calcium in vitro

A biomarker of increased risk for colon cancer is abnormally high proliferation of colonic epithelial cells. The authors developed an in vitro assay that measures the ability of human colonic epithelial cells that are in progressive stages of abnormal development to respond to direct application of calcium as the chloride in tissue culture medium. Incorporation of 3H-thymidine and autoradiography in situ was employed to measure the number of proliferating cells cultured at 0.1 mM CaCl2, the optimum level for growth, and 2.2 to 5 mM, both levels achievable in the colonic lumen. Abnormal cell proliferation was reduced in biopsies from 13 of 14 patients without familial polyposis but at increased risk for colon cancer because of previous colonic neoplasms or familial association; in cells from three of four asymptomatic individuals in familial polyposis families at risk for that disease; and in cells of three of ten patients symptomatic with familial polyposis. Growth of tubular adenoma cells from two of seven familial polyposis patients was also inhibited by calcium. Growth inhibition was not observed in more advanced colon tumors including eight adenomas, either villotubular or villous, and five carcinomas. These findings indicate heterogeneity within the familial polyposis phenotype for the normal cellular response to growth inhibition by calcium, and a further loss of response to calcium as these cells progress toward malignancy.     

12-O-Tetradecanoylphorbol-13-acetate stimulation of DNA synthesis in cultured preneoplastic familial polyposis colonic epithelial cells but not in normal colonic epithelial cells

We have developed a method for the routine primary culture of human colonic epithelial cells. Cultured cells exhibited characteristic epithelial structures, including a brush border and junctional complexes. Flask-like goblet cells containing mucus were also seen within the epithelial monolayer. [3H]Thymidine labeling indices were used to distinguish between cultured cells from familial polyposis patients, other patients at high risk to develop colon cancer, and low-risk control subjects. 12-O-Tetradecanoylphorbol-13-acetate (TPA) at 10 ng/ml enhanced DNA synthesis an average of 8-fold when assayed by labeling index in colonic epithelial cells from five of six familial polyposis patients. No such stimulation by TPA was seen in cells from 13 high-risk patients without familial polyposis or in cells from five low-risk subjects. Hundreds of benign polyps can be found in the colons of familial polyposis patients. One such benign tubular adenoma exhibited the same enhancement of DNA synthesis by TPA as normal-appearing epithelial cells from a biopsy adjacent to that polyp. Mitogenic response to TPA had been seen earlier in cells from each of four tubular adenomas (Friedman, E. Cancer Res., 41: 4588-4599, 1981). Both familial polyposis epithelial cells and adenoma cells are considered preneoplastic, but they are not identical because their patterns of actin cytoskeletal organization differ. These results imply that familial polyposis epithelial cells are precursors of tubular adenoma cells, and their transition to the more advanced preneoplastic cells of this benign tumor is influenced by endogeneous tumor promoters.     

Causes of death in patients with familial polyposis coli (FPC)

Autopsy reports from patients with familial polyposis coli were obtained from the Roswell Park Memorial Institute Registry as well as clinical data on patients with familial polyposis coli with regard to their causes of death. Although the latter group did not undergo autopsy they were the subject of a close follow-up. From this data it is clear that diagnosis at an early age may not diminish the chances of the patient with familial polyposis to develop cancer. Removal of the colonic mucosa does not provide absolute assurance that patients with this condition will be cured, as these patients remain at considerable risk for developing other benign and malignant lesions of the gastrointestinal tract and perhaps also of other organs. Close follow-up of FPC patients who have had surgery for colorectal polyps or cancer is necessary. Other proliferative abnormalities of FPC patients include an abnormal fibroblastic response, tendency to develop adhesions, and the propensity for developing desmoids. Desmoids may follow a slow but unrelenting course with a lethal outcome. Autopsy findings support the view that there should be no distinction between familial polyposis coli and Gardner's syndrome.     

The prognostic and clinicopathological roles of microsatellite instability,PD-L1 expression and tumor-infiltrating leukocytes in familial adenomatous polyposis

BackgroundMicrosatellite instability, programmed death-ligand 1 and tumor-infiltrating leukocytes are prognostic biomarkers in colorectal cancer but unknown toward familial adenomatous polyposis.AimTo investigate the prognostic and clinicopathological roles of microsatellite instability, programmed death-ligand 1 and tumor-infiltrating leukocytes in familial adenomatous polyposis.MethodsClinical data and paraffin embedded tissues from 45 familial adenomatous polyposis patients were collected. Microsatellite instability was detected by immunohistochemistry and polymerase chain reaction. Programmed death-ligand 1 was detected by immunohistochemistry. Tumor-infiltrating leukocytes comprising CD8⁺ T cells, M1 and M2 tumor associated macrophages, CD56^bright and CD56^dim natural killer cells were analyzed using multiple fluorescence immunohistochemistry.ResultsMicrosatellite instability high was noted in 6 samples but not associated with overall survival or progression-free survival. Programmed death-ligand 1 is negative on tumor cells but positive on tumor-infiltrating leukocytes, and positive programmed death-ligand 1 expression on tumor-infiltrating leucocytes is associated with overall survival. Low CD56^bright natural killer cell infiltration was associated with longer progression-free survival and was an independent prognostic factor in FAP.ConclusionFor familial adenomatous polyposis, microsatellite instability high can be found but has no correlation with prognosis; programmed death-ligand 1 on tumor-infiltrating leukocytes is related with overall survival; CD56^bright natural killer cell is an independent prognostic factor associating with longer progression-free survival.     

Total gastrectomy with isoperistaltic jejunal interposition flap for symptomatic management of gastric polyposis from familial adenomatous polyposis

Patients with familial adenomatous polyposis (FAP) oftentimes have extracolonic polyps. The patient discussed in this case report had innumerable gastric polyps which were significantly affecting his ability to tolerate oral intake and his overall nutrition. Medical management was not sufficiently controlling his symptoms; therefore we proceeded with surgical intervention. We discuss the use of a total gastrectomy with an Isoperistaltic jejunal interposition flap for the symptomatic management of gastric polyposis. We describe the technique used and benefits to this specific procedure when it comes to long term outcome, complications, and monitoring.     

Genetic testing for young-onset colorectal cancer: case report and evidence-based clinical guidelines

BACKGROUND: Young-onset colorectal cancer is clinicopathologically different from older-onset colorectal cancer and tends to occur in patients with hereditary germline conditions such as Lynch syndrome and familial adenomatous polyposis. CASE REPORT.: We describe the case of a 44-year-old man with a paternal history of colon polyps, a personal 2-year history of hematochezia, and a diagnosis of rectal cancer. Further clinical evaluation of the patient at our institution determined the cancer to be stage IIIA. The patient underwent genetic counseling and testing, which indicated he was negative for the most common familial cancer syndromes. After treatment with neoadjuvant chemoradiotherapy, surgery, and adjuvant chemotherapy, the patient has done well. We review the hereditary cancer syndromes and genetic tests to consider for patients with early-onset colorectal cancer. CONCLUSIONS: This case underscores the importance of following cancer-screening guidelines.     

The clinical approach to a patient with multiple polyps

There are many factors to consider in managing patients with multiple polyps. Familial adenomatous polyposis, attenuated familial adenomatous polyposis, MUTYH-associated polyposis, and the hamartomatous and hyperplastic polyposis syndromes should be considered in the differential diagnosis. Family history helps determine which genetic tests to offer in confirming a diagnosis. A genetic diagnosis allows relatives to undergo predictive testing and helps to streamline surgical and screening recommendations for patients and their relatives. Knowledge about etiology, natural history, and genetics of the polyposis syndromes has guided clinical management recommendations for these patients. Nevertheless, it is important to recognize that most patients with multiple adenomatous or hyperplastic polyps do not have a known genetic condition.     

Chemoprevention of carcinogenesis in familial tumors

Among familial cancers, chemoprevention has been studied for familial adenomatous polyposis, hereditary nonpolyposis colorectal cancers, and familial breast cancers. This report reviews the studies on chemoprevention in familial adenomatous polyposis. A large number of clinical trials have been performed using sulindac, a non-steroidal anti-inflammatory drug (NSAID). Sulindac reduces the size and number of large-bowel polyps. However, as yet, it cannot be used for this indication in the clinical setting, because of the frequent occurrence of serious gastrointestinal side effects, and there are a number of patients in whom aggressive tumors developed despite a reduction in the size of polyps. Studies of cyclooxygenase-2 (COX-2) selective inhibitors, with minimal side effects on the digestive tract, are showing promising results. In addition to NSAIDs, clinical trials have been performed using vitamins and dietary components. These show minimal side effects, but their efficacy is still insufficient for clinical use, and further studies are anticipated.     

Frequency and phenotypic spectrum of germline mutations in POLE and seven other polymerase genes in 266 patients with colorectal adenomas and carcinomas

In a number of families with colorectal adenomatous polyposis or suspected Lynch syndrome/HNPCC, no germline alteration in the APC, MUTYH, or mismatch repair (MMR) genes are found. Missense mutations in the polymerase genes POLE and POLD1 have recently been identified as rare cause of multiple colorectal adenomas and carcinomas, a condition termed polymerase proofreading‐associated polyposis (PPAP). The aim of the present study was to evaluate the clinical relevance and phenotypic spectrum of polymerase germline mutations. Therefore, targeted sequencing of the polymerase genes POLD1, POLD2, POLD3, POLD4, POLE, POLE2, POLE3 and POLE4 was performed in 266 unrelated patients with polyposis or fulfilled Amsterdam criteria. The POLE mutation c.1270C>G;p.Leu424Val was detected in four unrelated patients. The mutation was present in 1.5% (4/266) of all patients, 4% (3/77) of all familial cases and 7% (2/30) of familial polyposis cases. The colorectal phenotype in 14 affected individuals ranged from typical adenomatous polyposis to a HNPCC phenotype, with high intrafamilial variability. Multiple colorectal carcinomas and duodenal adenomas were common, and one case of duodenal carcinoma was reported. Additionally, various extraintestinal lesions were evident. Nine further putative pathogenic variants were identified. The most promising was c.1306C>T;p.Pro436Ser in POLE. In conclusion, a PPAP was identified in a substantial number of polyposis and familial colorectal cancer patients. Screening for polymerase proofreading mutations should therefore be considered, particularly in unexplained familial cases. The present study broadens the phenotypic spectrum of PPAP to duodenal adenomas and carcinomas, and identified novel, potentially pathogenic variants in four polymerase genes.