Risk-reducing surgery in hereditary gynecological cancer: Clinical applications in Lynch syndrome and hereditary breast and ovarian cancer

Targeted sequencing for hereditary breast and ovarian cancer in BRCA1/2-negative families reveals complex genetic architecture and phenocopies

Approximately 20% of breast cancer cases are attributed to increased family risk, yet variation in BRCA1/2 can only explain 20%-25% of cases. Historically, only single gene or single variant testing were common in at-risk family members, and further sequencing studies were rarely offered after negative results. In this study, we applied an efficient and inexpensive targeted sequencing approach to provide molecular diagnoses in 245 human samples representing 134 BRCA mutation-negative (BRCAX) hereditary breast and ovarian cancer (HBOC) families recruited from 1973 to 2019 by Dr. Henry Lynch. Sequencing identified 391 variants, which were functionally annotated and ranked based on their predicted clinical impact. Known pathogenic CHEK2 breast cancer variants were identified in five BRCAX families in this study. While BRCAX was an inclusion criterion for this study, we still identified a pathogenic BRCA2 variant (p.Met192ValfsTer13) in one family. A portion of BRCAX families could be explained by other hereditary cancer syndromes that increase HBOC risk: Li-Fraumeni syndrome (gene: TP53) and Lynch syndrome (gene: MSH6). Interestingly, many families carried additional variants of undetermined significance (VOUSs) that may further modify phenotypes of syndromic family members. Ten families carried more than one potential VOUS, suggesting the presence of complex multi-variant families. Overall, nine BRCAX HBOC families in our study may be explained by known likely pathogenic/pathogenic variants, and six families carried potential VOUSs, which require further functional testing. To address this, we developed a functional assay where we successfully re-classified one family's PMS2 VOUS as benign.

Risk-Reducing Breast and Gynecological Surgery for BRCA Mutation Carriers: A Narrative Review

This narrative review aims to clarify the role of breast and gynecological risk-reduction surgery in BRCA mutation carriers. We examine the indications, contraindications, complications, technical aspects, timing, economic impact, ethical issues, and prognostic benefits of the most common prophylactic surgical options from the perspectives of a breast surgeon and a gynecologist. A comprehensive literature review was conducted using the PubMed/Medline, Scopus, and EMBASE databases. The databases were explored from their inceptions to August 2022. Three independent reviewers screened the items and selected those most relevant to this review's scope. BRCA1/2 mutation carriers are significantly more likely to develop breast, ovarian, and serous endometrial cancer. Because of the Angelina effect, there has been a significant increase in bilateral risk-reducing mastectomy (BRRM) since 2013. BRRM and risk-reducing salpingo-oophorectomy (RRSO) significantly reduce the risk of developing breast and ovarian cancer. RRSO has significant side effects, including an impact on fertility and early menopause (i.e., vasomotor symptoms, cardiovascular disease, osteoporosis, cognitive impairment, and sexual dysfunction). Hormonal therapy can help with these symptoms. Because of the lower risk of developing breast cancer in the residual mammary gland tissue after BRRM, estrogen-only treatments have an advantage over an estrogen/progesterone combined treatment. Risk-reducing hysterectomy allows for estrogen-only treatments and lowers the risk of endometrial cancer. Although prophylactic surgery reduces the cancer risk, it has disadvantages associated with early menopause. A multidisciplinary team must carefully inform the woman who chooses this path of the broad spectrum of implications, from cancer risk reduction to hormonal therapies.

Cost-effectiveness Analysis of Genotype-Specific Surveillance and Preventive Strategies for Gynecologic Cancers Among Women With Lynch Syndrome

IMPORTANCE

With the expansion of multigene testing for cancer susceptibility, Lynch syndrome (LS) has become more readily identified among women. The condition is caused by germline pathogenic variants in DNA mismatch repair genes (ie, MLH1, MSH2, MSH6, and PMS2) and is associated with high but variable risks of endometrial and ovarian cancers based on genotype. However, current guidelines on preventive strategies are not specific to genotypes.

OBJECTIVE

To assess the cost-effectiveness of genotype-specific surveillance and preventive strategies for LS-associated gynecologic cancers, including a novel, risk-reducing surgical approach associated with decreased early surgically induced menopause.

DESIGN, SETTING, AND PARTICIPANTS

This economic evaluation developed a cohort-level Markov simulation model of the natural history of LS-associated gynecologic cancer for each gene, among women from ages 25 to 75 years or until death from a health care perspective. Age was varied at hysterectomy and bilateral salpingo-oophorectomy (hyst-BSO) and at surveillance initiation, and a 2-stage surgical approach (ie, hysterectomy and salpingectomy at age 40 years and delayed oophorectomy at age 50 years [hyst-BS]) was included. Extensive 1-way and probabilistic sensitivity analyses were performed.

INTERVENTIONS

Hyst-BSO at ages 35 years, 40 years, or 50 years with or without annual surveillance beginning at age 30 years or 35 years or hyst-BS at age 40 years with oophorectomy delayed until age 50 years.

MAIN OUTCOMES AND MEASURES

Incremental cost-effectiveness ratio (ICER) between management strategies within an efficiency frontier.

RESULTS

For women with MLH1 and MSH6 variants, the optimal strategy was the 2-stage approach, with respective ICERs of $33 269 and $20 008 compared with hyst-BSO at age 40 years. Despite being cost-effective, the 2-stage approach was associated with increased cancer incidence and mortality compared with hyst-BSO at age 40 years for individuals with MLH1 variants (incidence: 7.76% vs 3.84%; mortality: 5.74% vs 2.55%) and those with MSH6 variants (incidence: 7.24% vs 4.52%; mortality: 5.22% vs 2.97%). Hyst-BSO at age 40 years was optimal for individuals with MSH2 variants, with an ICER of $5180 compared with hyst-BSO at age 35 years, and was associated with 4.42% cancer incidence and 2.97% cancer mortality. For individuals with PMS2 variants, hyst-BSO at age 50 years was optimal and all other strategies were dominated; hyst-BSO at age 50 years was associated with an estimated cancer incidence of 0.68% and cancer mortality of 0.29%.

CONCLUSIONS AND RELEVANCE

These findings suggest that gene-specific preventive strategies for gynecologic cancers in LS may be warranted and support hyst-BSO at age 40 years for individuals with MSH2 variants. For individuals with MLH1 and MSH6 variants, these findings suggest that a novel 2-stage surgical approach with delayed oophorectomy may be an alternative to hyst-BSO at age 40 years to avoid early menopause, and for individuals with PMS2 variants, the findings suggest that hyst-BSO may be delayed until age 50 years.

Current Approaches to Fertility Preservation

The 5 principal reasons a patient may consider fertility preservation are: treatment for cancer that may affect fertility, treatment for nonmalignant medical conditions that may affect fertility, planned indications, planned gender-affirming hormone therapy or surgery, or in the setting of genetic conditions that may increase the risks of premature ovarian insufficiency or early menopause. This paper will focus on describing who may consider preserving their fertility, how to provide the best clinical evaluation of those seeking fertility preservation, and current and future fertility preservation techniques. Last, we will highlight a need to continue to expand access to fertility preservation technologies.