Selected aspects of genetic counselling for BRCA1 mutation carriers

This work consists of six parts based on seven manuscripts dealing with some aspects of genetic counselling for BRCA1 mutation carriers. It was demonstrated that the risk of breast and ovarian cancer in first-degree relatives of BRCA1 mutation carriers depends on the type of mutation and is higher in the younger generation. It was also shown that risk of breast cancer, but not of ovarian cancer, is related to cancer type of the proband. These factors should be taken into account when assessing risk of breast and ovarian cancer in relatives of BRCA1 mutation carriers. It was observed that longer breast-feeding, physical activities delaying menarche, preventive oophorectomy, administration of tamoxifen to patients with intact genital tract, and use of contraceptives reduce the risk of breast and ovarian cancer. All these possibilities should be presented to BRCA1 mutation carriers within the framework of cancer risk reduction options. It was also observed that there may be some preference in transmission of the mutant allele to female offspring of BRCA1 founder mutation carriers. Environmental factors appear also to interfere with transmission. The male to female ratio in offspring of BRCA1 mutation carriers is the same as for the general population. As for the consequences of simplified two-stage genetic counselling, the first psychological reaction of a female to the fact that she is a carrier of the BRCA1 mutation is negative. However, understanding that the risk of cancer is high persuades the woman to embrace preventive options. 98% of BRCA1 mutation carriers disclosed during population screening initiated and promoted by the media are convinced of the value of genetic testing. Simplified two-stage genetic counselling appears to be a useful approach promoting increased turnout for BRCA1 mutation testing

Evaluation of Microfluidics-FISH method in prenatal diagnosis

Objectives: Classical cytogenetic analysis remains a gold standard in invasive prenatal diagnosis. Recently, Microfluidics¬-FISH, a novel method based on FISH, has been introduced. This integral approach allows to obtain result for common aneuploidies within the same day from a much smaller sample of the amniotic fluid. In this study we compare effectiveness of Microfluidics-FISH to classical karyotype and Rapid FISH. Material and methods: 52 samples of amniotic fluid were drawn from the pregnant women due to common indications. Cell cultures have been set up for classical cytogenetic analysis as well as amniotic cells have been loaded into the microchip of Microfluidics-FISH as well standard procedure of Rapid FISH was performed for evaluation of trisomy 21, 13, 18 chromosome and sex chromosomes numeric aberrations. Results: 9 samples out of 52 showed chromosomal aberrations in both FISH methods what was consistent with karyoty¬ping. One case of small supernumerary marker chromosome was detected only in the classical cytogenetic analysis. For the majority of cases turnaround time was shortest for Microfluidics-FISH and the average volume of sample was smallest. Microfluidics-FISH proved to be reliable and cost-effective rapid testing method of common aneuploidies. Recognizing, ho¬wever, limitations of methods based on FISH it cannot replace conventional karyotyping and be the sole method of diagnosis

Frequency of "BRCA1" and "BRCA2" causative founder variants in ovarian cancer patients in South-East Poland

Background Causative variants in BRCA1 and BRCA2 are well-established risk factors for breast and ovarian cancer. In Poland, the causative founder variants in the BRCA1 are responsible for a significant proportion of ovarian cancer cases, however, regional differences in the frequencies of various mutations may exist. The spectrum and frequency of BRCA1/2 mutations between ovarian cancer patients have not yet been studied in the region of South-East Poland. Methods We examined 158 consecutive unselected cases of ovarian cancer patients from the region of Podkarpacie. We studied 13 Polish causative founder variants in BRCA1 (c.5266dupC, c.4035delA, c.5251C > T, c.181 T > G, c.676delT, c.68_69delAG, c.3700_3704delGTAAA, c.1687C > T, c.3756_3759delGTCT) and in BRCA2 (c.658_659delGT, c.7910_7914delCCTTT, c.3847_3848delGT, c.5946delT). Results A BRCA1 causative founder variants were detected in 10 of the 158 (6.3%) ovarian cancer cases. BRCA2 causative founder variants were not observed. The c.5266dupC mutation was detected in 6 patients, c.181 T > G mutation in 3 patients and the c.676delT mutation in 1 patient. The median age of diagnosis of the 10 hereditary ovarian cancers was 55.5 years of age. Conclusions The frequency of 13 causative founder variants in Podkarpacie was lower than in other regions of Poland. Testing of three BRCA1 mutations (c.5266dupC, c.181 T > G, c.676delT) should be considered a sensitive test panel

Large deletion causing von Hippel-Lindau disease and hereditary breast cancer syndrome

Patients with intragenic mutations of the VHL gene have a typical disease presentation. However in cases of large VHL gene deletions which involve other genes in the proximity of the VHL gene a presentation of the disease can be different. To investigate whether large VHL deletions that remove the FANCD2 gene have an effect on the disease phenotype, we studied a family with a 50 kb large deletion encompassing these two genes. Four patients in this family were affected by VHL-related lesions. However one carrier of the deletion also had bilateral ductal breast cancer at age 46 and 49. Both tumors were of ~2 cm in diameter. On one side lymph nodes were affected. One tumor was ER- and PR-negative (HER2 s unknown) and the second was ER- and PR-positive, and HER2-negative. Our study suggests that a deletion of FANCD2 gene, an important gene in the DNA repair pathway, may be associated with an increased risk of breast cancer, but further studies are needed in this regard

Charakterystyka wybranych aspektów klinicznych u kobiet, nosicielek mutacji genu BRCA1 poddanych operacjom profilaktycznym narządu płciowego leczonych uprzednio z powodu raka piersi

Aim: Evaluation of patient age and time of the prophylactic surgery, as well as incidence of genital cancers and precancerous states observed in histopathology of the postoperative material from BRCA1 gene mutation carriers previously treated for breast cancer. Material and methods: 206 carriers of one of the three most common BRCA1 gene mutations (5382insC, C61G and 4153delA) in the Polish population, who were offered the option of prophylactic salpingo-oophorectomy. The study group comprised 85 patients with the diagnosis of breast cancer before gynecological preventive surgery. The study group was further divided into two subgroups for more detailed assessment of the tested variables. The first subgroup included 67 patients with breast cancer (unilateral or bilateral synchronous). The second subgroup included 18 patients with bilateral metachronous (the second diagnosis of breast cancer was at least 12 months after the first breast cancer diagnosis). The control group consisted of 121 patients with no cancerous lesions before preventive gynecologic surgery. The patients undergoing prophylactic treatment had no prior symptoms in female sexual organ and no changes in the diagnostic tests. Results: The patients with a history of breast cancer underwent genetic testing and preventive surgery of the genital tract at a significantly later age than controls (respectively, p = 0.0003, p = 0.0006). The patients with bilateral metachronous breast cancer underwent preventive surgery significantly earlier (p = 0.03). There was a trend indicating a 2.5 times higher risk of developing ovarian cancer among BRCA1 mutation carriers who had already been diagnosed and treated for breast cancer, when compared to women without breast cancer diagnosis. The incidence of other genital cancers and precancerous states in BRCA1 gene mutation carriers with history of breast cancer was not statistically significant as compared to controls. Data on the clinical stage, morphological grade, histological type, age and type of pathology, and the type of BRCA1 gene mutation did not show a statistically significant difference between the groups. Conclusions: Each patient diagnosed with breast cancer should be strongly recommended a genetic test to reduce adverse consequences resulting from postponing the test and, if applicable, the preventive operation until later in life. Preventive surgery should be considered especially in BRCA1 gene mutation carriers previously treated for breast cancer because of the increased risk of ovarian cancer.Cel pracy: Ocena wieku i czasu wykonania operacji profilaktycznej oraz częstości występowania raków i stanów przedrakowych narządu płciowego stwierdzanych w badaniu histopatologicznym materiału pooperacyjnego u pacjentek nosicielek mutacji genu BRCA1 leczonych uprzednio z powodu raka piersi. Materiał i metody: Materiał stanowiło 206 pacjentek nosicielek jednej z trzech najczęstszych mutacji dla populacji polskiej (5382insC, 4153delA i C61G) genu BRCA1 (16), którym przedstawiono jako opcję – zabieg profilaktycznego usunięcie przydatków. U pacjentek wykonano operacje profilaktyczne w okresie od 15.09.1999r. do 31.12.2010r. Były to kolejne nosicielki mutacji pochodzące z województwa zachodniopomorskiego, operowane w Katedrze i Klinice Ginekologii Operacyjnej i Onkologii Ginekologicznej Dorosłych i Dziewcząt PUM w Szczecinie. Wyniki: U pacjentek poddanych zabiegowi profilaktycznemu wcześniej nie stwierdzono jakichkolwiek objawów ze strony narządu płciowego i zmian w badaniach diagnostycznych. Grupę badaną (A) stanowiło 85 pacjentek leczonych przed operacją profilaktyczną z powodu raka piersi. W celu dokładniejszej oceny badanych zmiennych grupę badaną A podzielono dodatkowo na dwie podgrupy: B i C. Do podgrupy B włączono 67 pacjentek z rakiem piersi ( jednej piersi lub obustronnym rakiem - zdiagnozowanym w tym samym czasie). Do podgrupy C włączono 18 pacjentek z obustronnym rakiem piersi zdiagnozowanym w różnym czasie, czas jaki upłynął od pierwszej diagnozy wynosił co najmniej 12 miesięcy). Grupę kontrolną (K) stanowiło 121 pacjentek, u których przed operacją profilaktyczną nie stwierdzono żadnych nowotworów złośliwych. W grupie badanych pacjentek porównywano wiek i czas od podjęcia decyzji dotyczącej zabiegu profilaktycznego do wieku pacjentek i czasu poddania się przez nie operacji. Wnioski: Każdej pacjentce, z rozpoznanym rakiem piersi należy zdecydowanie zaproponować wykonanie badanie genetycznego, aby zmniejszyć niekorzystne tendencje późniejszego zgłaszania się na badania genetyczne i w związku z tym wykonywania operacji profilaktycznej w późniejszym wieku. Wykonanie operacji profilaktycznej szczególnie należy rozważyć u pacjentek, nosicielek mutacji genu BRCA1, leczonych w przeszłości z powodu raka piersi z uwagi na wzrost ryzyka zachorowania na raka jajnika

Blood Arsenic Levels as a Marker of Breast Cancer Risk among BRCA1 Carriers

Funding Information: Funding: The study was funded by the National Centre for Research and Development Projects. INNOMED/1/16/NCBR/2014 and PBS3/B7/26/2015. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.An important group of breast cancers is those associated with inherited susceptibility. In women, several predisposing mutations in genes involved in DNA repair have been discovered. Women with a germline pathogenic variant in BRCA1 have a lifetime cancer risk of 70%. As part of a larger prospective study on heavy metals, our aim was to investigate if blood arsenic levels are associated with breast cancer risk among women with inherited BRCA1 mutations. A total of 1084 participants with pathogenic variants in BRCA1 were enrolled in this study. Subjects were followed from 2011 to 2020 (mean follow-up time: 3.75 years). During that time, 90 cancers were diagnosed, including 67 breast and 10 ovarian cancers. The group was stratified into two categories (lower and higher blood As levels), divided at the median (<0.85 µg/L and ≥0.85 µg/L) As level among all unaffected participants. Cox proportional hazards models were used to model the association between As levels and cancer incidence. A high blood As level (≥0.85 µg/L) was associated with a significantly increased risk of developing breast cancer (HR = 2.05; 95%CI: 1.18–3.56; p = 0.01) and of any cancer (HR = 1.73; 95%CI: 1.09–2.74; p = 0.02). These findings suggest a possible role of environmental arsenic in the development of cancers among women with germline pathogenic variants in BRCA1.Peer reviewe