Genetic predisposition in gynecologic cancers

Fertility Preservation in BRCA1/2 Germline Mutation Carriers: An Overview

BRCA1 and BRCA2 mutations are responsible for a higher incidence of breast and ovarian cancer (from 55% up to 70% vs. 12% in the general population). If their functions have been widely investigated in the onset of these malignancies, still little is known about their role in fertility impairment. Cancer patients treated with antineoplastic drugs can be susceptible to their gonadotoxicity and, in women, some of them can induce apoptotic program in premature ovarian follicles, progressive depletion of ovarian reserve and, consequently, cancer treatment-related infertility (CTRI). BRCA variants seem to be associated with early infertility, thus accelerating treatment impairment of ovaries and making women face the concrete possibility of an early pregnancy. In this regard, fertility preservation (FP) procedures should be discussed in oncofertility counseling-from the first line of prevention with risk-reducing salpingo-oophorectomy (RRSO) to the new experimental ovarian stem cells (OSCs) model as a new way to obtain in vitro-differentiated oocytes, several techniques may represent a valid option to BRCA-mutated patients. In this review, we revisit knowledge about BRCA involvement in lower fertility, pregnancy feasibility, and the fertility preservation (FP) options available.

Germline multigene panel testing of patients with endometrial cancer

Endometrial cancer (EC) is the most common gynecological malignancy in developed countries. The present study aimed to determine the frequency of germline pathogenic variants (PV) in patients with EC. In this multicenter retrospective cohort study, germline genetic testing (GGT) was performed in 527 patients with EC using a next generation sequencing panel targeting 226 genes, including 5 Lynch syndrome (LS) and 14 hereditary breast and ovarian cancer (HBOC) predisposition genes, and 207 candidate predisposition genes. Gene-level risks were calculated using 1,662 population-matched controls (PMCs). Patients were sub-categorized to fulfill GGT criteria for LS, HBOC, both or none. A total of 60 patients (11.4%) carried PV in LS (5.1%) and HBOC (6.6%) predisposition genes, including two carriers of double PV. PV in LS genes conferred a significantly higher EC risk [odds ratio (OR), 22.4; 95% CI, 7.8-64.3; P=1.8×10^-17] than the most frequently altered HBOC genes BRCA1 (OR, 3.9; 95% CI, 1.6-9.5; P=0.001), BRCA2 (OR, 7.4; 95% CI, 1.9-28.9; P=0.002) and CHEK2 (OR, 3.2; 95% CI, 1.0-9.9; P=0.04). Furthermore, >6% of patients with EC not fulfilling LS or HBOC GGT indication criteria carried a PV in a clinically relevant gene. Carriers of PV in LS genes had a significantly lower age of EC onset than non-carriers (P=0.01). Another 11.0% of patients carried PV in a candidate gene (the most frequent were FANCA and MUTYH); however, their individual frequencies did not differ from PMCs (except for aggregated frequency of loss-of-function variants in POLE/POLD1; OR, 10.44; 95% CI, 1.1-100.5; P=0.012). The present study demonstrated the importance of GGT in patients with EC. The increased risk of EC of PV carriers in HBOC genes suggests that the diagnosis of EC should be included in the HBOC GGT criteria.

Lynch Syndrome and Gynecologic Tumors: Incidence, Prophylaxis, and Management of Patients with Cancer

This review provides a comprehensive update on recent evidence regarding gynecologic tumors associated with Lynch Syndrome (LS). Endometrial cancer (EC) and ovarian cancer (OC) are the first and second most common gynecologic malignancies in developed countries, respectively, and LS is estimated to be the hereditary cause in 3% of both EC and OC. Despite the increasing evidence on LS-related tumors, few studies have analyzed the outcomes of LS-related EC and OC stratified by mutational variant. This review aims to provide a comprehensive overview of the literature and comparison between updated international guidelines, to help outline a shared pathway for the diagnosis, prevention, and management of LS. Through the widespread adoption of the immunohistochemistry-based Universal Screening, LS diagnosis and identification of mutational variants could be standardized and recognized by international guidelines as a feasible, reproducible, and cost-effective method. Furthermore, the development of a better understanding of LS and its mutational variants will support our ability to better tailor EC and OC management in terms of prophylactic surgery and systemic treatment in the light of the promising results shown by immunotherapy.

Hereditary Gynecologic Cancer Syndromes - A Narrative Review

Hereditary cancer syndromes are defined as syndromes, where the genetics of cancer are the result of low penetrant polymorphisms or of a single gene disorder inherited in a mendelian fashion. During the last decade, compelling evidence has accumulated that approximately 5-10% of all cancers could be attributed to hereditary cancer syndromes. A tremendous progress has been made over the last decade in the evaluation and management of these syndromes. However, hereditary syndromes associated with gynecologic malignancies still present significant challenge for oncogynecologists. Oncogynecologists tend to pay more attention to staging, histological type and treatment options of gynecological cancers than thinking of inherited cancers and taking a detailed family history. Moreover, physicians should also be familiar with screening strategies in patients with inherited gynecological cancers. Lynch syndrome and hereditary breast-ovarian cancer syndrome are the most common and widely discussed syndromes in medical literature. The aim of the present review article is to delineate and emphasize the majority of hereditary gynecological cancer syndromes, even these, which are rarely reported in oncogynecology. The following inherited cancers are briefly discussed: Lynch syndrome; "site-specific" ovarian cancer and hereditary breast-ovarian cancer syndrome; Cowden syndrome; Li-Fraumeni syndrome; Peutz-Jeghers syndrome; ataxia-telangiectasia; DICER1- syndrome; gonadal dysgenesis; tuberous sclerosis; multiple endocrine neoplasia type I, II; hereditary small cell carcinoma of the ovary, hypercalcemic type and hereditary undifferentiated uterine sarcoma; hereditary diffuse gastric cancer and MUTYH-associated polyposis. Epidemiology, pathogenesis, diagnosis, pathology and screening of these syndromes are discussed. General treatment recommendations are beyond the scope of this review.

Inherited rare and common variants in PTCH1 and PTCH2 contributing to the predisposition to reproductive cancers

PTCH1 and PTCH2 are associated with nevoid basal cell carcinoma syndrome and basal cell carcinoma. We determined the prevalence of their common and rare variants in 877 patients with various reproductive cancers and 296 healthy subjects. Using targeted next-generation sequencing, we found significantly statistical associations of the minor alleles at seven common variants of PTCH1 and PTCH2 with a decreased risk of reproductive cancers (P = 9.69 × 10^-12). Among these variants, two haplotype blocks in high linkage disequilibrium were consisted of rs2277184, rs2066829 and rs2236405 sites at PTCH1 and rs3795720, rs11573590 and rs11211040 sites at PTCH2. Single marker and haplotype-based analysis consistently revealed a decreased risk of reproductive cancers especially breast and prostate cancers in the subjects carrying the minor alleles, and on the contrary, an increased risk for major alleles. Healthy control subjects showed a higher rate of rare variants than that of cancer patients (P = 0.017). Notably, two frameshift variants (p.Ser391* and p.Cys101Alafs*48) of PTCH2 with deleterious effects were found in only four cancer patients. Higher frequencies of variants of PTCH genes might have a protective role against the development of reproductive cancers, whereas rare deleterious variants of PTCH2 might predispose a carrier to reproductive cancers.

Surgical treatment and fertility perservation in endometrial cancer

Background

Endometrial cancer (EC) represents a high health burden in Slovenia and worldwide. The incidence is increasing due to lifestyle and behavioural risk factors such as obesity, smoking, oestrogen exposure and aging of the population. In many cases, endometrial cancer is diagnosed at an early stage due to obvious signs and symptoms. The standard treatment is surgery with or without adjuvant therapy, depending on the stage of the disease and the risk of recurrence. However, treatment modalities have changed in the last decades, considerably in the extent of lymphadenectomy.

Conclusions

The gold standard of treatment for is surgery, which may be the only treatment modality in the early stages of low-grade tumours. In recent years, a minimally invasive approach with sentinel node biopsy (SNB) has been proposed. A conservative approach with hormonal treatment is used if fertility preservation is desired. If EC is in advance stage, high-risk histology, or high grade, radiotherapy, chemotherapy, or a combination of both is recommended.

Hereditary ovarian tumour syndromes: current update on genetics and imaging

Hereditary ovarian tumour syndromes are a diverse group of hereditary syndromes characterised by the development of specific histotypes of ovarian neoplasms. While BRCA syndromes are exclusively associated with high-grade serous carcinomas, patients with Lynch syndrome show a preponderance of endometrioid subtype of ovarian and endometrial carcinomas. Distinct non-epithelial phenotypes, such as sex cord stromal tumours with annular tubules, Sertoli-Leydig cell tumours, and small cell carcinoma of the hypercalcaemic type occur in patients with Peutz-Jeghers, DICER1, and rhabdoid tumour predisposition syndromes, respectively. Gorlin-Goltz syndrome is characterised by the development of bilateral, multiple ovarian fibromas in 14-24% of patients. Ovarian steroid cell tumours and broad ligament papillary cystadenomas are characteristically found in women with von Hippel-Lindau syndrome. Recent studies have allowed the characterisation of tumour genetics and associated oncological pathways that contribute to tumourigenesis. Implications of the diagnosis of these syndromes on screening, management, and prognosis are discussed.

An Analysis of Clinical, Surgical, Pathological and Molecular Characteristics of Endometrial Cancer According to Mismatch Repair Status. A Multidisciplinary Approach

Since 2016, our hospital has applied tumor testing with immunohistochemistry (IHC) in endometrial cancer in order to detect mutations of mismatch repair genes (MMR). All cases with MMR deficiency proteins expression are sent for genetic testing, except those with MLH1 protein deficiency, in which case genetic testing is performed if negative for promoter hypermethylation. The primary aim of this study was to investigate the ability of our algorithm to identify Lynch syndrome (LS). The Secondary aims were to investigate the relationship between MMR status and clinicopathological features and prognosis of primary endometrial cancer (EC). From January 2016 to December 2018, 239 patients with EC were retrospectively analyzed and subdivided according to MMR status. Patients were divided in three groups: MMR proficient, LS and Lynch-like cancer (LLC). LS was characterized by a lower age and BMI, more use of contraceptive and less use of hormonal replacement therapy, nulliparity and a trend versus a better prognosis. LLC appeared more related to MMR proficient than LS and exhibited a more aggressive behavior. Our multidisciplinary approach permitted a correct diagnosis of germline mutation in patients with newly diagnosis EC and it confirmed clinicopathologic and prognostic characteristics of LS.

Inherited cancer syndromes in 220 Italian ovarian cancer patients

BACKGROUND

A subsets of ovarian carcinomas (OCs) are related to inherited conditions including Hereditary Breast and Ovarian Cancers (HBOC) and Lynch Syndrome (LS). The identification of inherited conditions using genetic testing might be a strategic model for cancer prevention that include benefits for the ovarian cancer patients and for their family members.

METHODS

We describe a retrospective Italian experience for the identification of inherited conditions in 232 patients affected by OCs using both somatic and germline analyses.

RESULTS

Immunohistochemical and microsatellite analyses performed on OCs identified 20 out of 101 MMR defective cancers and 15 of these were from patients carriers of the MMR germline pathogenetic variants. BRCA1 and BRCA2 testing offered to 198 OC patients revealed 67 (34%) pathogenetic variant carriers of BRCA1/2 genes. Interestingly LS patients revealed a mean age of OC onset of 45.4 years, which was significantly lower than the mean age of OCs onset of HBOC patients.

CONCLUSIONS

Somatic and germline analyses offered to OC patients has proved to be an efficient strategy for the identification of inherited conditions involving OC also in absence of suggestive family histories. The identification of LS and HBOC syndromes through OC patients is an effective tool for OC prevention.

Women's preferences for cancer risk management strategies in Lynch syndrome

OBJECTIVE

We assessed preferences for cancer risk management strategies for Lynch syndrome (LS) in LS-affected women.

METHODS

Women with LS aged ≥25 years evaluated 9 cancer risk management strategies using a visual analog scale (VAS) and modified standard gamble (SG). For the VAS, women ranked each strategy ranging from 0 (least preferred) to 100 (most preferred). VAS scores were calculated by dividing the corresponding number by 100. Scores closer to 1.0 reflected more favorable strategies. For the SG, participants were asked to specify their expected threshold of lifetime risk of endometrial or colorectal cancer, ranging from 0 to 100%, at which they would consider undertaking each strategy. Strategies included chemoprevention, cancer screening, and preventive surgery. Cancer worry and perceived cancer risk measures were collected on a subset of participants.

RESULTS

Sixty-one women completed preference assessments. By VAS, annual combined screening was the most preferred, followed by annual screenings and chemoprevention with oral contraceptives. By SG, women were the most willing to endorse oral contraceptives and biannual screening strategies at the lowest threshold of lifetime risk followed by annual screening strategies. Surgical interventions were the least preferred strategies using both VAS and SG. Women with a family history of gynecologic or colorectal cancer were less likely to consider prevention or screening options compared to women without a family history. Cancer worry was higher among women with a positive family history of LS cancer.

CONCLUSION

Understanding women's preferences may facilitate optimal use and adherence to cancer risk management strategies.

Recommendations and Choices for BRCA Mutation Carriers at Risk for Ovarian Cancer: A Complicated Decision

Current ovarian cancer screening guidelines in high-risk women vary according to different organizations. Risk reducing surgery remains the gold standard for definitive treatment in BRCA mutation carriers, but research advancements have created more short-term options for patients to consider. The decisions involved in how a woman manages her BRCA mutation status can cause a great deal of stress and worry due to the imperfect therapy options. The goal of this review was to critically analyze the screening recommendations and alternative options for high-risk ovarian cancer patients and evaluate how these discrepancies and choices affect a woman’s management decisions.

Population pharmacokinetics of ABT-767 in BRCA1 or BRCA2 mutation carriers with advanced solid tumors or in subjects with high grade serous ovarian, primary peritoneal or fallopian tube cancer

PURPOSE

The objective of the manuscript is to describe the development of a population pharmacokinetic model for ABT-767, a potent and orally bioavailable inhibitor of poly (ADP-ribose) polymerase enzyme, and to evaluate the potential influence of patient demographics and baseline covariates on the pharmacokinetics of ABT-767.

METHODS

A total of 1809 plasma ABT-767 concentrations from 90 subjects were used for population pharmacokinetic modeling. Covariates screened for influence on pharmacokinetic parameters were body weight, lean body weight, body surface area, albumin, creatinine clearance, serum creatinine, liver function tests, and age. The effect of food on absorption and bioavailability were also evaluated. Model validation was performed using bootstrap analysis and visual predictive check.

RESULTS

A two-compartment model with firstorder absorption adequately described the pharmacokinetics of ABT-767. The population estimates of apparent clearance from central compartment (CL/F), volume of central compartment (V _c/F), and absorption rate constant (k _a) were 7.34 L/h, 25.8 L, 1.45 h^-1, respectively. The estimates of interindividual variabilities (%CV) in CL/F, V _c/F, and k _a were 40.4, 40.5, and 53.8%, respectively. The k _a was influenced by food. Albumin on CL/F was a statistically significant covariate; however, it explained only 8% of the variability in the pharmacokinetics of ABT-767.

CONCLUSIONS

Albumin on CL/F was the only statistically significant baseline covariate affecting ABT-767 pharmacokinetics, but it only explained a fraction of the pharmacokinetic variability. Dosage adjustments based on body size, age, or mild renal impairment are not needed for ABT-767. The developed model will be used to evaluate ABT-767 exposure-response analyses and to perform simulations for different dose and dosing regimens.