Use of family history in a screening clinic for familial ovarian cancer

The association of low penetrance genetic risk modifiers with colorectal cancer in lynch syndrome patients: a systematic review and meta-analysis

Lynch syndrome (LS) is a highly penetrant inherited cancer predisposition syndrome accounting for approximately 1000 cases of colorectal cancer (CRC) in the UK annually. LS is characterised by autosomal dominant inheritance and germline mutations in DNA mismatch repair genes. The penetrance is highly variable and the reasons for this have not been fully elucidated. This study investigates whether low penetrance genetic risk factors may result in phenotype modification in LS patients. To conduct a systematic literature review and meta-analysis to assess the association between low penetrance genetic risk modifiers and CRC in LS patients. A systematic review was conducted of the PubMed and HuGENet databases. Eligibility of studies was determined by pre-defined criteria. Included studies were analysed via the per-allele model and assessed by pooled odds ratios and establishing 95% confidence intervals. Study heterogeneity was assessed via Cochrane's Q statistic and I2 values. Publication bias was evaluated with funnel plots. Subgroup analysis was conducted on gender. Statistical software used was the Metafor package for the R programme version 3.1.3. Sixty-four polymorphisms were identified and sufficient data was available for analysis of ten polymorphisms, with between 279 and 1768 CRC cases per polymorphism. None demonstrated association with CRC risk in LS patients. However in sub-group analysis the polymorphism rs16892766 (8q23.3) was significant in males (OR 1.53, 95% CI 1.12-2.10). The variable phenotype presentation of the disease still remains largely unexplained, and further investigation is warranted. Other factors may also be influencing the high variability of the disease, such as environmental factors, copy number variants and epigenetic alterations. Investigation into these areas is needed as well as larger and more definitive studies of the polymorphisms analysed in this study.

Cancer screening in a high risk population: a clinical trial

The purpose of this paper is to report the results of screening high risk women for ovarian cancer using endovaginal ultrasound (EVUS), color flow Doppler and cancer antigen (CA) 125. A total of 252 women were recruited with a family history of ovarian cancer in at least 1 first-degree relative. All women underwent a pelvic examination and EVUS twice during the first year and annually thereafter. Of 210 premenopausal women in the study, 14 underwent surgery. Of these, 2 were based on the endovaginal ultrasound (US) results and proved to be false-positive. There were 48 postmenopausal women who underwent 9 operations. Of these, 2 were stimulated by finding a thickened stripe on EVUS, and proved to be endometrial carcinomas. There were 2 ovarian cancers, both advanced, 1 colon cancer and 1 renal cell cancer. Of the women, 6 had a history of breast cancer and 11 more developed it during the study. This high-risk population has a very high prevalence of breast cancer, and mammography must be a part of ovarian cancer screening programs.

A systematic review and meta-analysis of family history and risk of ovarian cancer

OBJECTIVE

To estimate the relative risk and lifetime risk of ovarian cancer in women with various categories of family history.

DESIGN

A meta-analysis of all published case-control and cohort studies.

METHODS

Pooled relative risk estimates were calculated for the case control studies, using the Mantel-Haenzel method. These estimates were combined with the relative risks from the cohort studies. The pooled estimates of relative risk were used to estimate lifetime risks of ovarian cancer from age 15 up to age 75, for various categories of family history.

MAIN OUTCOME MEASURES

Relative risks and lifetime risks of developing ovarian cancer were calculated for the categories of women with 1. an affected first degree relative; 2. an affected mother; 3. an affected sister; and 4. women with more than one affected relative.

RESULTS

The relative risk to first degree relatives is 3.1 (95% CI 2.6-3.7). There is some evidence that this relative risk declines with age. The relative risk to mothers of cases 1.1 (95% CI 0.8-1.6) was lower than the relative risks to sisters: 3.8 (95% CI 2.9-5.1), and daughters: 6.0 (95% CI 3.0-11.9); the explanation of this difference is unclear.

CONCLUSIONS

Women with a family history of ovarian cancer have a substantially higher risk of developing ovarian cancer compared with women without such a history. However the risk is small for most categories of family history, except for the small number of individuals who have more than one affected relative.

Family history: a comprehensive genetic risk assessment method for the chronic conditions of adulthood

Targeting individuals with increased risk for common, chronic disease can improve the efficiency and efficacy of preventive efforts by improving the predictability of screening tests and participant compliance. Individuals with the greatest risk for these disorders are those with a genetic susceptibility. The purpose of this study was to determine the feasibility of using a single, comprehensive family history as a method for stratifying risk for many preventable, common genetic disorders. Family histories obtained in a prenatal diagnostic clinic were reviewed regarding cardiovascular diseases, diabetes and several cancers; 42.5% of individuals reported a family history for at least one of the disorders under study. Familial coronary artery disease was most commonly reported (29% of participants), followed by noninsulin-dependent diabetes (14%). Qualitative characterization of disease susceptibility was also accomplished using family history data. For example, occurrence of different cancers within pedigrees was suggestive of familial cancer syndromes, and clustering of noninsulin-dependent diabetes and cardiovascular disease suggested an insulin resistance syndrome. Depending on the specific disease, 5 to 15% of at-risk individuals had a moderately increased risk (2 to 5 times the population risk), and approximately 1 to 10% had a high risk (absolute risks approaching 50%). Family history reports of common, chronic disease are prevalent among the population at large, and collection and interpretation of comprehensive family history data is a feasible, initial method for risk stratification for many preventable, chronic conditions. These findings may have important implications for disease prevention and management.

Family history in ovarian cancer referral population

In order to determine the incidence of familial and hereditary ovarian cancer in a referral patient population, we conducted a retrospective study of 44 patients from a consecutive set of 62 patients treated for ovarian carcinoma at the Gynecologic Oncology Clinic at the Richland Memorial Hospital Center for Cancer Treatment and Research between January 1, 1993 and December 31, 1993. In our study of the referred patients, only two (4.55%) reported a history of at least one first-degree relative also being affected with ovarian cancer. However, 13 patients (29.55%) reported a family history consistent with one of the hereditary ovarian cancer syndromes. In addition to having a suggestive family history, these 13 families demonstrated several cardinal features of hereditary cancer syndromes including early onset, bilaterality, multiple primary tumors, and transmission. Race was the only significantly different demographic factor between the hereditary and sporadic ovarian cancer groups. All 13 patients who appeared to have a hereditary form of cancer were Caucasian.

Screening for early familial ovarian cancer with transvaginal ultrasonography and colour blood flow imaging

OBJECTIVE

To assess the value of transvaginal ultrasonography with colour blood flow imaging in detecting early ovarian cancer in women with a family history of the disease.

DESIGN

Study of self referred symptomless women with a close relative who had developed the disease. Each woman was screened to detect persistent lesions and defined changes in ovarian volume. Morphological score and pulsatility index were recorded.

SETTING

Ovarian screening clinic.

SUBJECTS

1601 self referred women.

INTERVENTIONS

Women with a positive screening result were recommended to have further investigations.

MAIN OUTCOME MEASURES

Findings at surgery and histology of abnormal ovaries. Morphological score > or = 5 and pulsatility index < 1.0 at last scan.

RESULTS

Women were aged 17 to 79 (mean 47) years; 959 (60%) were premenopausal, 469 (29%) were naturally postmenopausal, and 173 (11%) had had a hysterectomy. 157 women had a pedigree suggestive of the site specific ovarian cancer syndrome and 288 of multiple site cancers. 61 women had a positive screening result (3.8%, 95% confidence interval 2.9 to 4.9%), six of whom had primary ovarian cancer detected at surgery (five stage Ia, one stage III). Use of a high morphological score or a low pulsatility index increased the odds of finding ovarian cancer from 1:9 to about 2:5 (1:1 in the highest risk groups). Five interval cancers were reported (three ovarian and two peritoneal). Eight of the 11 cancers developed in women with pedigrees suggestive of inherited cancer.

CONCLUSIONS

Transvaginal ultrasonography with colour flow imaging can effectively detect early ovarian cancer in women with a family history of the disease. The screening interval should be less than two years.

Correlation in ages at death from familial ovarian cancer among sisters

The analysis of pedigrees taken from 97 of 1466 women attending a screening clinic for early familial ovarian cancer showed that there was a strong correlation in the ages at death from the disease among sisters (r = 0.68, confidence limits 0.51-0.82, P < 0.001), but not between mothers and daughters. This information can be used to help counsel women who are considering the appropriate time for more intensive screening or prophylactic oophorectomy.