Universal genetic testing for women with newly diagnosed breast cancer in the context of multidisciplinary team care

Uptake and patient-related outcomes of mainstreaming genetic testing: a systematic review and meta-analysis

OBJECTIVE

Mainstreaming genetic testing refers to genetic testing for cancer susceptibility genes following cancer diagnosis, which is provided by nongenetic health professionals of the cancer-treating team. Mainstreaming can be used to guide cancer treatment and secondary cancer prevention in the patient and to identify carriers in the family members of patients who test positive through cascade testing. We aimed to assess uptake and patient-reported outcomes of mainstreaming genetic testing.

DATA SOURCES

We searched PubMed and the Cochrane Library from inception to June 2024.

STUDY ELIGIBILITY CRITERIA

Our population included adult patients offered mainstreaming genetic testing (intervention). Outcomes included testing uptake, satisfaction, decisional conflict/regret, anxiety, depression, and cancer-related distress.

STUDY APPRAISAL AND SYNTHESIS METHODS

We followed a prospective protocol according to Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines (International Prospective Register of Systematic Reviews: CRD42023467312). Qualitative synthesis and random effects meta-analyses were performed. Quality assessment was performed using the Methodological Index for Non-Randomized Studies.

RESULTS

Searches yielded 5314 studies; 29 studies (n=13,219) were included, of which 14 were on ovarian cancer (n=6039), 6 on breast cancer (n=4354), 3 on prostate cancer (n=772), 1 on endometrial cancer (n=302), and 5 on multiple cancers (n=1752). There were no studies for colorectal cancer. Pooled genetic testing uptake was 91% (95% confidence interval=86-96, I2=99.6%, n=5942) across all cancers. Unselected testing uptake was 95% (95% confidence interval=92-98, I2=98.4%, n=3946), while family history/clinical criteria-based testing uptake was 80% (95% confidence interval=63-97, I2=99.0%, n=1996). Uptake for ovarian cancer cases was 93% (95% confidence interval=88-98, I2=98.6%, n=2801), for breast cancer 95% (95% confidence interval=90-99, I2=94.78%, n=981), for endometrial cancer 99% (95% confidence interval=98-100, I2=0.0%, n=304), and for prostate cancer 73% (95% confidence interval=47-99, I2=98.8%, n=772). Pooled pretest 24.24 (95% confidence interval: 23.34-24.14, I2=93.0%) and post-test 16.11 (95% confidence interval: 15.27-16.96, I2=80.3%). Decisional Conflict Scale scores were low (3 studies, n=681), decreasing from pretest to post-test (P=.03). On qualitative synthesis, pretest and post-test satisfaction scores were high (14 studies, n=3093). Decisional regret (4 studies, n=393), pretest and post-test depression scales (2 studies, n=252), and post-test distress (5 studies, n=773) were low. There was variability in reported pretest (low to high, 4 studies, n=1079) and post-test anxiety (low to moderate, 5 studies, n=1231) and pretest distress (low to moderate, 2 studies, n=594).

CONCLUSION

Mainstreaming genetic testing uptake is associated with high uptake and satisfaction and low decision conflict, regret, and post-test distress. Quality and quantity of evidence across different types of cancers vary significantly.

Short-term Patient-Reported Outcomes Following Bilateral Risk-Reducing Mastectomy for Patients at a High Risk for Breast Cancer: A Systematic Review

BACKGROUND

Bilateral risk-reducing mastectomies (RRMs) have been proven to decrease the risk of breast cancer in patients at high risk owing to family history or having pathogenic genetic mutations. However, few resources with consolidated data have detailed the patient experience following surgery. This systematic review features patient-reported outcomes for patients with no breast cancer history in the year after their bilateral RRM.

METHODS

The databases MEDLINE, Embase, and Scopus were used to identify studies. Studies were then evaluated by multiple authors, and their quality was assessed by using the Methodological Index for Non-Randomized Studies score.

RESULTS

Our search identified 1858 unique studies, of which 11 met our inclusion criteria. Only two of these studies included patients who did not receive postmastectomy reconstruction. The included studies were either retrospective cohort studies or prospective studies. General satisfaction with the outcome of RRM and the decision to undergo RRM was high across many of the studies, with low levels of regret. There was also a noticeable trend of improved psychosocial outcomes following RRM. For postoperative sexual well-being, body image, aesthetic satisfactions, and somatosensory function, there were a mix of positive and negative outcomes.

CONCLUSIONS

The patients who elected to manage their breast cancer risk with bilateral RRM (mostly with reconstruction) tend to be satisfied with their decision and the surgical outcomes. This may be related to decreased cancer-related anxiety. Postmastectomy psychosocial well-being tends to improve while physical health after surgery varies by patient.

Clinical, histological and receptor profiles of invasive breast cancer and ductal carcinoma in situ in females with germline pathogenic variants in PTEN and implications for germline testing

PTEN hamartoma tumour syndrome (PHTS) is an autosomal dominant hereditary cancer syndrome, caused mostly by germline pathogenic variants in PTEN. Female carriers have an up to 80% lifetime risk of breast cancer. Pathological features of breast cancer in PHTS have seldom been reported. In a collaboration between all histopathology laboratories in our state and our statewide familial cancer service, we tracked the breast biopsies of 12 females with known PTEN pathogenic or likely pathogenic (P/LP) variants (January 1990 to January 2018). Two further cases were added by a Victorian cancer genetics unit. Breast cancer, inclusive of invasive cancer or ductal carcinoma in situ (DCIS), was diagnosed in 12 of 14 cases (85.7%). One case had a family history of PHTS, and six had a family history of breast cancer. The mean age at first breast cancer diagnosis was 41.6 years (range 27-63). Six cases developed more than one breast cancer. Five (42%) developed contralateral breast cancer. Ten of the 12 invasive cancers were of no special type, and two were reported as lobular carcinomas. None were grade 1. When reported, all cancers were hormone-receptor positive and HER2 negative. All were associated with DCIS. The DCIS spanned all grades. The two cases without breast cancer still required surgery for exuberant benign changes, including papillomas, fibroadenomatoid change, florid ductal epithelial hyperplasia, adenosis ​and stromal fibrosis. We note that the morphology and receptor profiles of breast cancer in individuals with P/LP PTEN variants are not distinctive. Contrary to prevalent beliefs, these cancers do not conform to the contemporary definition of apocrine breast carcinoma. Greater familiarity of healthcare professionals with the overall clinical and pathological findings in PHTS and the validated Cleveland Clinic PTEN calculator (http://www.lerner.ccf.org/gmi/ccscore) would improve the recognition of female PHTS individuals with breast cancer. Earlier identification of their cancer predisposition syndrome would benefit these patients and their families who are at high risk of a range of cancers.

Reduced Breast and Ovarian Cancer Through Targeted Genetic Testing: Estimates Using the NEEMO Microsimulation Model

Background: The effectiveness and cost-effectiveness of genetic testing for hereditary breast and ovarian cancer largely rely on the identification and clinical management of individuals with a pathogenic variant prior to developing cancer. Simulation modelling is commonly utilised to evaluate genetic testing strategies due to its ability to synthesise collections of data and extrapolate over long time periods and large populations. Existing genetic testing simulation models use simplifying assumptions for predictive genetic testing and risk management uptake, which could impact the reliability of their estimates. Our objective was to develop a microsimulation model that accurately reflects current genetic testing and subsequent care in Australia, directly incorporating the dynamic nature of predictive genetic testing within families and adherence to cancer risk management recommendations. Methods: The populatioN gEnEtic testing MOdel (NEEMO) is a population-level microsimulation that incorporates a detailed simulation of individuals linked within five-generation family units. The genetic component includes heritable high- and moderate-risk monogenic gene variants, as well as polygenic risk. Interventions include clinical genetic services, breast screening, and risk-reducing surgery. Model validation is described, and then to illustrate a practical application, NEEMO was used to compare clinical outcomes for four genetic testing scenarios in patients newly diagnosed with breast cancer (BC) and their relatives: (1) no genetic testing, (2) current practice, (3) optimised referral for genetic testing, and (4) genetic testing for all BC. Results: NEEMO accurately estimated genetic testing utilisation according to current practice and associated cancer incidence, pathology, and survival. Predictive testing uptake in first- and second-degree relatives was consistent with known prospective genetic testing data. Optimised genetic referral and expanded testing prevented up to 9.3% of BC and 4.1% of ovarian cancers in relatives of patients with BC. Expanding genetic testing eligibility to all BC patients did not lead to improvement in life-years saved in at-risk relatives compared to optimised referral of patients eligible for testing under current criteria. Conclusions: NEEMO is an adaptable and validated microsimulation model for evaluating genetic testing strategies. It captures the real-world uptake of clinical and predictive genetic testing and recommended cancer risk management, which are important considerations when considering real-world clinical and cost-effectiveness.

Establishment of a clinical cancer genetics program for breast cancer in a resource-limited country; challenges and opportunities

Breast cancer is the most common cancer among women worldwide, and its incidence rate is still increasing, especially among younger women. Nationally, it constitutes one-fifth of all cancer cases and almost 40% of all female cancers. With a median age of 51 years, breast cancer is diagnosed at least a decade earlier, and at more advanced stages compared to Western societies. Hereditary cancers account for 10% or more of all cancer burden worldwide. With expanded indications, increased number of genes tested, and significant decline in cost of testing, such proportion will probably increase. Individuals with pathogenic variants of BRCA1 and BRCA2 are at higher risk of breast, ovarian, pancreatic and many other cancers. Over the past two decades, several highly penetrant cancer-susceptibility genes were identified across almost all tumor sites, thus increasing the need for comprehensive cancer genetic programs that address the testing process, counselling patients and at-risk family members, and then deal with all testing results and its consequences. In addition to its important role in preventing more cancers in index patients themselves and among their close relatives, identification of pathogenic or likely pathogenic variants, mostly in BRCA1 or BRCA2, may inform therapeutic decisions in common cancers including breast, ovarian, prostate and pancreatic cancers. In this manuscript, we describe the experience of a comprehensive cancer center, in a resource-limited country in establishing a comprehensive clinical cancer genetics program that can serve as an example for others who share similar demographic and financial restrains.

Screening guidelines for individuals at increased risk for prostate cancer

Individuals at increased risk for prostate cancer (PCa) are inconsistently defined in national and international guidelines. The National Comprehensive Cancer Network (NCCN) defines people at increased risk for PCa to include those with a concerning family history, West African/Caribbean/African-American individuals, and those who have germline mutations in known PCa-related genes. Recommendations for screening are also inconsistently defined in national and international guidelines. The NCCN and American Urological Association recommend that individuals at increased risk for PCa be screened with prostate-specific antigen and digital rectal exam starting at age 40. Defining increased risk groups and defining lifetime risk is an ongoing academic process that can be facilitated through patient registries of these cohorts at academic centers.

Genetic Counseling, Testing, and Family Communication Into Survivorship After Diagnosis of Breast Cancer

PURPOSE

To examine receipt of genetic testing and communication with relatives about results into survivorship after diagnosis of breast cancer.

METHODS

Women age 20-79 years diagnosed with early-stage breast cancer in 2014-2015 and reported to the Georgia and Los Angeles County SEER registries were surveyed approximately 7 months and 6 years after diagnosis (n = 1,412). We asked about genetic counseling, testing, and communication with relatives about results. We categorized women into indications for testing on the basis of clinical guidelines at the time of diagnosis and at the time of the follow-up survey (FUPs).

RESULTS

A total of 47.4% had indications for genetic testing at any time: 28.0% at baseline and an additional 19.4% at the time of the FUPs (only); 71.9% (95% CI, 67.4 to 76.4) of those with a baseline indication reported genetic testing versus 53.3% (95% CI, 47.3 to 59.2) with an indication at FUPs only and 35.0% (95% CI, 31.6 to 38.4) with no indication (P < .001). There were no significant racial or ethnic differences in receipt of testing, controlling for age and clinical indications (P = .239); results for genetic counseling were similar. Only 3.4% of survivors had direct-to-consumer genetic testing (DTCt) for cancer. Testers who reported a pathogenic variant (n = 62) were much more likely to have talked to most or all their first-degree adult relatives about genetic testing than those with a variant of unknown significance (n = 49) or a negative finding (n = 419): 62.7% versus 38.8% and 38.0%, respectively (P < .001).

CONCLUSION

Many women with indications for genetic counseling and testing into survivorship do not receive it. But those tested reach out to family members on the basis of the clinical relevance of their results. Very few patients obtained DTCt, which suggests that these tests do not substitute for clinical testing in breast cancer survivors.

Management and Clinical Outcomes of Breast Cancer in Women Diagnosed with Hereditary Cancer Syndromes in a Clinic-Based Sample from Colombia

This study aimed to investigate prognosis and survival differences in 82 breast cancer patients with germline pathogenic/likely pathogenic variants (PVs) treated and followed at the Breast Unit of the Instituto Nacional de Cancerología, Colombia (INC-C) between 2018 and 2021. Median age at diagnosis was 46 years, with 62.2% presenting locally advanced tumors, 47.6% histological grade 3, and 35.4% with triple-negative breast cancer (TNBC) subtype. Most carriers, 74.4% (61/82), had PVs in known breast cancer susceptibility genes (i.e., "associated gene carriers" group, considered inherited breast cancer cases): BRCA2 (30), BRCA1 (14), BARD1 (4), RAD51D (3), TP53 (2), PALB2 (2), ATM (2), CHEK2 (1), RAD51C (1), NF1 (1), and PTEN (1). BRCA1-2 represented 53.7%, and homologous recombination DNA damage repair (HR-DDR) genes associated with breast cancer risk accounted for 15.9%. Patients with PVs in non-breast-cancer risk genes were combined in a different category (21/82; 25.6%) (i.e., "non-associated gene carriers" group, considered other breast cancer cases). Median follow-up was 38.1 months, and 24% experienced recurrence, with 90% being distant. The 5-year Disease-Free Survival (DFS) for inherited breast cancer cases was 66.5%, and for other breast cancer cases it was 88.2%. In particular, for carriers of PVs in the BRCA2 gene, it was 37.6%. The 5-year Overall Survival (OS) rates ranged from 68.8% for those with PVs in BRCA2 to 100% for those with PVs in other HR-DDR genes. Further studies are crucial for understanding tumor behavior and therapy response differences among Colombian breast cancer patients with germline PVs.

MAGENTA: a Multinational patient survey assessing the Awareness, perceptions and unmet needs in GENetic Testing and counselling among patients with breAst cancer

Objective

Genetic testing and counselling are critical in assessing breast cancer risk and tailoring treatment strategies. However, several barriers hinder patients from opting for genetic testing/counselling, leading to fewer than one-third of patients undergoing testing and even fewer being offered counselling. A granular understanding of these barriers is essential in overcoming them.

Methods

A multinational survey developed by patient authors was conducted in 9 countries, to identify the specific local/regional barriers. The survey question pathway was individualized, based on responses to prior questions. Percentage responses to a response option were calculated based on the total number of respondents to that question. Chi-square tests were used to assess the significance of the results, if applicable.

Results

The final analysis set (FAS) included 1,176 respondents, with a subset of this responding to all questions. In the FAS, 63% of respondents had undergone testing. Among those who got tested, 70% were offered testing. Among untested respondents, only 40% were offered the test but eventually did not get tested. In the tested population, 44% received counselling, which was significantly higher than 7% (p<0.00001) in the untested group. Among those reporting on awareness, 71% reported awareness level between 'very low' and 'moderate' prior to cancer diagnosis. Most respondents (71%) agreed that all breast cancer patients should undergo testing before treatment initiation. However, Asian patients were less likely to endorse this view compared to respondents from other regions (25% vs ≥50%; p<0.00001). A higher proportion of tested respondents were 'very willing' to get their family members tested (44%) versus untested respondents (11%), with relatively higher willingness among Australian (77%) and Russian respondents (56%), the regional variation being statistically significant (p<0.00001).

Conclusions

Critical gaps remain in the access, awareness and perceived value of genetic testing and counselling, with regional variance or difference between the tested and untested groups. Most patients are not offered counselling, which may be associated with the low uptake of testing. Strategic action is needed to drive policy-shaping and improve access to testing and counselling, including raising patient awareness and improving patient experience for better treatment outcomes.

BRCA testing and management of BRCA-mutated early-stage breast cancer: a comprehensive statement by expert group from GCC region

BReast CAncer (BRCA)1 and BRCA2 gene pathogenic variants account for most hereditary breast cancers (BC). Identification of BRCA mutations can significantly influence both prognosis and treatment outcomes. Furthermore, it enables the identification of individuals who are at heightened risk of developing BC due to inherited genetic mutations. Many developing countries rely on western guidelines for BRCA testing and BC management; however, there exist wide disparities in the prevalence of risk factors, availability of medical resources, and practice patterns. Guidelines tailored to specific regions can help mitigate healthcare variations, promote consistency in treatment, and aid healthcare providers in identifying effective therapies for improving patient outcomes. Hence, oncologists from the Gulf Cooperation Council (GCC) congregated virtually in March 2023 and reviewed existing data on the epidemiology of BC, BRCA mutations, practices and challenges associated with BRCA testing and management of BRCA mutated early-stage BC in the GCC region. They also provided insights on the real-world diagnostic and treatment practices and challenges in the GCC region in the BRCA-mutated early-stage BC domain and suggested some variations to international guidelines to aid their uptake in this region.

Economic evaluation of germline genetic testing for breast cancer in low- and middle-income countries: a systematic review

BACKGROUND

Breast cancer (BC) is the most common cancer affecting women globally. Genetic testing serves as a prevention and treatment strategy for managing BC. This study aims to systematically review economic evaluations and the quality of selected studies involving genetic screening strategies for BC in low and middle-income countries (LMICs).

METHODS

A search was performed to identify related articles that were published up to April 2023 on PubMed, Embase, CINAHL, Web of Science, and the Centre for Reviews and Dissemination. Only English-language LMIC studies were included. Synthesis of studies characteristics, methodological and data input variations, incremental cost-effectiveness ratios (ICERs), and reporting quality (Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 checklist) were performed.

RESULTS

This review found five pertinent studies, mainly focusing on economic evaluations of germline genetic testing in upper-middle-income countries (Upper MICs) like Malaysia, China, and Brazil. Only one study covered multiple countries with varying incomes, including lower-middle-income nations (Lower MICs) like India. The ICERs values in various screening scenarios for early-stage BC, HER2 negative BC patients, and healthy women with clinical or family history criteria were ranging from USD 2214/QALY to USD 36,342/QALY. Multigene testing for all breast cancer patients with cascade testing was at USD 7729/QALY compared to BRCA alone. Most studies adhered to the CHEERS 2022 criteria, signifying high methodological quality.

CONCLUSIONS

Germline testing could be considered as cost-effective compared to no testing in Upper MICs (e.g., Malaysia, China, Brazil) but not in Lower MICs (e.g., India) based on the willingness-to-pay (WTP) threshold set by each respective study. Limitations prevent a definite conclusion about cost-effectiveness across LMICs. More high-quality studies are crucial for informed decision-making and improved healthcare practices in these regions.

Universal Germline-Genetic Testing for Breast Cancer: Implementation in a Rural Practice and Impact on Shared Decision-Making

BACKGROUND

Whereas the National Comprehensive Cancer Network (NCCN) criteria restrict germline-genetic testing (GGT) to a subset of breast cancer (BC) patients, the American Society of Breast Surgeons recommends universal GGT. Although the yield of pathogenic germline variants (PGV) in unselected BC patients has been studied, the practicality and utility of incorporating universal GGT into routine cancer care in community and rural settings is understudied. This study reports real-world implementation of universal GGT for patients with breast cancer and genetics-informed, treatment decision-making in a rural, community practice with limited resources.

METHODS

From 2019 to 2022, all patients with breast cancer at a small, rural hospital were offered GGT, using a genetics-extender model. Statistical analyses included Fisher's exact test, t-tests, and calculation of odds ratios. Significance was set at p < 0.05.

RESULTS

Of 210 patients with breast cancer who were offered GGT, 192 (91.4%) underwent testing with 104 (54.2%) in-criteria (IC) and 88 (45.8%) out-of-criteria (OOC) with NCCN guidelines. Pathogenic germline variants were identified in 25 patients (13.0%), with PGV frequencies of 15 of 104 (14.4%) in IC and ten of 88 (11.4%) in OOC patients (p = 0.495). GGT informed treatment for 129 of 185 (69.7%) patients.

CONCLUSIONS

Universal GGT was successfully implemented in a rural, community practice with > 90% uptake. Treatment was enhanced or de-escalated in those with and without clinically actionable PGVs, respectively. Universal GGT for patients with breast cancer is feasible within rural populations, enabling optimization of clinical care to patients' genetic profile, and may reduce unnecessary healthcare, resource utilization.

Management of breast cancer patients with BRCA gene mutations in Jordan: perspectives and challenges

BACKGROUND

This paper explores and discusses local challenges oncologists face for diagnosing and managing breast cancer patients with BRCA gene mutations in Jordan.

METHODS

A task force involving key opinion leaders, experts in the management of breast cancer, and stakeholders in healthcare systems where genetic testing is available in Jordan discussed current evidence and local real-life practice. The task force then formulated recommendations to achieve better patient outcomes and satisfaction based on evidence-based medicine and their clinical experience in BRCA-mutated breast cancer management.

RESULTS AND CONCLUSION

Eligibility of patients for genetic testing, physician acceptance and willingness to integrate genetic testing into routine practice is encouraging but remains restricted by testing availability and financial coverage. Until more data is available, genetic testing should be targeted for breast cancer patients based on tumor subtypes, as well as family and personal history of cancer, as per international guidelines. Whenever possible, genetic testing should aim to detect all actionable genes through a multigene panel including BRCA1/2. Major challenges faced in clinical practice in Jordan include fear of genetic discrimination and social stigmatization, as well as hesitancy toward risk-reducing surgery. Pre-testing counseling is therefore critical to promote acceptance of genetic testing. Since geneticists are in short supply in Jordan, genetic counseling can be offered through a specially trained genetic counselor or through a hybrid system that includes oncologist-based counselling. In addition to cancer prevention, germline genetic testing may assist in the selection of specific anti-cancer therapy, such as PARP inhibitors, in patients with BRCA1/2 mutation. Nationwide initiatives are also needed to ensure access to PARP inhibition therapy and provide financial coverage for genetic screening, mastectomies and reconstructive surgery across Jordan.