The impact of hysterectomy on subsequent colonoscopy in women with Lynch Syndrome.

BACKGROUND AND AIMS: Women with Lynch Syndrome (LS) have a high risk of colorectal and endometrial cancer. They are recommended regular colonoscopies, and some choose prophylactic hysterectomy. The aim of this study was to determine the impact of hysterectomy on subsequent colonoscopy in these women. MATERIALS AND METHODS: A total of 219 LS women >30 years of age registered in the clinical registry at Section for Hereditary Cancer, Oslo University Hospital, were included. Data included hysterectomy status, other abdominal surgeries, and time of surgery. For colonoscopies, data were collected on cecal intubation rate, challenges, and level of pain. Observations in women with and without hysterectomy, and pre- and post-hysterectomy were compared. RESULTS: Cecal intubation rate was lower in women with hysterectomy than in those without (119/126 = 94.4% vs 88/88 = 100%, p = 0.025). Multivariate regression analysis showed an increased risk of challenging colonoscopies (OR,3.58; CI: 1.52-8.43; p = 0.003), and indicated a higher risk of painful colonoscopy (OR, 3.00; 95%CI: 0.99-17.44, p = 0.052), in women with hysterectomy compared with no hysterectomy. Comparing colonoscopy before and after hysterectomy, we also found higher rates of reported challenging colonoscopies post-hysterectomy (6/69 = 8.7% vs 23/69 = 33.3%, p < 0.001). CONCLUSIONS: Women with hysterectomy had a lower cecal intubation rate and a higher number of reported challenging colonoscopy than women with no hysterectomy. However, completion rate in the hysterectomy group was still as high as 94.4%. Thus, LS women who consider hysterectomy should not be advised against it.

APC mosaicism in a young woman with desmoid type fibromatosis and familial adenomatous polyposis.

Familial adenomatous polyposis (FAP) is usually caused by germline mutations in the adenomatous polyposis coli (APC) gene. The classic form is characterized by hundreds to thousands of adenomas in the colorectum and early onset colorectal cancer (CRC) if left untreated. FAP is also associated with multiple extra-colonic manifestations such as gastroduodenal polyps, osteomas, epidermoid cysts, fibromas and desmoids. Most desmoid tumours in FAP patients occur intra-abdominally. Approximately 15-20% of the APC mutations are de novo mutations. Somatic mosaicism has been reported in some sporadic cases of polyposis but is probably an underestimated cause of the disease. This case report presents the detection of a mosaic APC mutation in a 26-year-old woman who as a child had been diagnosed with desmoid type fibromatosis. FAP was suggested when she presented with extensive extra abdominal fibromatosis. Our findings indicate that APC mutations may be suspected in patients presenting with a desmoid regardless of its location. If there is clinical evidence that the patient has FAP, adenomas and colonic mucosa in addition to leukocyte DNA should be included in the screening, preferably using methods that are more sensitive than Sanger sequencing.

Survival in women with MMR mutations and ovarian cancer: a multicentre study in Lynch syndrome kindreds.

BACKGROUND: Women with a germline mutation in one of the MMR genes MLH1, MSH2 or MSH6 reportedly have 4-12% lifetime risk of ovarian cancer, but there is limited knowledge on survival. Prophylactic bilateral salpingo-oophorectomy (PBSO) has been suggested for preventing this condition. AIM: The purpose of this retrospective multicentre study was to describe survival in carriers of pathogenic mutations in one of the MMR genes, and who had contracted ovarian cancer. METHODS: Women who had ovarian cancer, and who tested positive for or were obligate carriers of an MMR mutation, were included from 11 European centres for hereditary cancer. Most women had not attended for gynaecological screening. Crude and disease specific survival was calculated by the Kaplan-Meier algorithm. RESULTS: Among the 144 women included, 81.5% had FIGO stage 1 or 2 at diagnosis. 10 year ovarian cancer specific survival independent of staging was 80.6%, compared to less than 40% that is reported both in population based series and in BRCA mutation carriers. Disease specific 30 year survival for ovarian cancer was 71.5%, and for all hereditary non-polyposis colon cancer (HNPCC)/Lynch syndrome related cancers including ovarian cancer it was 47.3%. CONCLUSIONS: In the series examined, infiltrating ovarian cancer in Lynch syndrome had a better prognosis than infiltrating ovarian cancer in BRCA1/2 mutation carriers or in the general population. Lifetime risk of ovarian cancer of about 10% and a risk of dying of ovarian cancer of 20% gave a lifetime risk of dying of ovarian cancer of about 2% in female MMR mutation carriers.

Germ-line mutations in mismatch repair genes associated with prostate cancer.

Genetic predisposition to prostate cancer includes multiple common variants with a low penetrance (single nucleotide polymorphisms) and rare variants with higher penetrance. The mismatch repair (MMR) genes MLH1, MSH2, MSH6, and PMS2 are associated with Lynch syndrome where colon and endometrial cancers are the predominant phenotypes. The purpose of our study was to investigate whether germ-line mutations in these genes may be associated with prostate cancer. One hundred and six male carriers or obligate carriers of MMR mutations were identified. Nine had contracted prostate cancer. Immunohistochemical analysis was done on tumor tissue from eight of the nine tumors. Observed incidence, cumulative risk at 60 and 70 years of age, age of onset, and Gleason score were compared with expected as assessed from population-based series. Absence of gene product from the mutated MMR gene was found in seven of eight tumors. Expected number of prostate cancers was 1.52 compared with 9 observed (P < 0.01). Mean age of onset of prostate cancer was 60.4 years compared with 66.6 expected (P = 0.006); the number of men with a Gleason score between 8 and 10 was significantly higher than expected (P < 0.00001). Kaplan-Meier analysis suggested that cumulative risk by 70 years in MMR mutation carriers may be 30% (SE, 0.088) compared with 8.0% in the general population. This is similar to the high risk associated with BRCA2 mutations. To our knowledge, this study is the first to indicate that the MMR genes may be among the rare genetic variants that confer a high risk of prostate cancer when mutated.