Implementation of Universal Pan-Cancer Germline Genetic Testing in an Arab Population: The Jordanian Exploratory Cancer Genetics Study.

PURPOSE: Germline genetic testing (GGT) significantly affects cancer care. While universal testing has been studied in Western societies, less is known about adoption elsewhere. MATERIALS AND METHODS: In this study, 3,319 unselected, pan-cancer Jordanian patients diagnosed between April 2021 and September 2022 received GGT. Pathogenic germline variant (PGV) frequency among patients who were in-criteria (IC) or out-of-criteria (OOC; 2020 National Comprehensive Cancer Network criteria) and changes in clinical management in response to GGT results were evaluated. Statistical analysis was performed using two-tailed Fisher's exact test with significance level P < .05. RESULTS: The cohort was predominantly female (69.9%), with a mean age of 53.7 years at testing, and 53.1% were IC. While patients who were IC were more likely than patients who were OOC to have a PGV (15.8% v 9.6%; P < .0001), 149 (34.8%) patients with PGVs were OOC. Clinical management recommendations in response to GGT, including changes to treatment and/or follow-up, were made for 57.3% (161 of 281) of patients with high- or moderate-risk PGVs, including 26.1% (42 of 161) of patients who were OOC. CONCLUSION: Universal GGT of patients with newly diagnosed cancer was successfully implemented in Jordan and led to identification of actionable PGVs that would have been missed with guidelines-based testing.

Germline Pathogenic Variants Identified in Patients With Genitourinary Malignancies Undergoing Universal Testing: A Multisite Single-Institution Prospective Study.

PURPOSE: This study aimed to investigate the prevalence of pathogenic germline variants (PGVs) in hereditary cancer genes utilizing a universal testing approach and to determine the rate of PGVs that would have been missed based on National Comprehensive Cancer Network (NCCN) guidelines in genitourinary (GU) malignancies. MATERIALS AND METHODS: A multisite, single-institution prospective germline genetic test (GGT) was universally offered to patients with new or active diagnoses of GU malignancies (prostate, bladder, and renal) from April 2018 to March 2020 at Mayo Clinic sites. Participants were offered GGT using a next-generation sequencing panel of > 80 genes. Demographic, tumor characteristics, and genetic results were evaluated. NCCN GU cancer guidelines were used to identify whether patients had incremental findings, defined as PGV-positive patients who would not have received testing based on NCCN guidelines. RESULTS: Of 3095 individuals enrolled in the study, 601 patients had GU cancer (prostate = 358, bladder = 106, and renal = 137). The mean enrollment age was 67 years (SD 9.1), 89% were male, and 86% of patients were non-Hispanic White. PGVs were identified in 82 (14%) of all GU patients. PGV prevalence breakdown by cancer type was: 14% prostate, 14% bladder, and 13% renal cancer. Nearly one-third of identified PGVs were high penetrance, and the majority of these (67%) were clinically actionable. Incremental PGVs were identified in 28 (57%) prostate, 15 (100%) bladder, and 14 (78%) renal cancer patients. Of the 82 patients with PGV findings, 29 (35%) had at least 1 relative undergo cascade testing for the familial variant(s) identified. CONCLUSIONS: More than 1 in 8 patients with GU malignancies were found to carry a PGV, with 67% of patients with high-penetrance PGVs undergoing clinically actionable changes. The majority of these PGVs would not have been identified based on current testing criteria. These findings support universal GGT for GU malignancies and underscore its potential to enhance risk assessment and guide precision interventions in urologic oncology.

Germline cancer susceptibility in individuals with melanoma.

BACKGROUND: Prior studies have estimated a small number of individuals with melanoma (2%-2.5%) have germline cancer predisposition, yet a recent twin study suggested melanoma has the highest hereditability among cancers. OBJECTIVE: To determine the incidence of hereditary melanoma and characterize the spectrum of cancer predisposition genes that may increase the risk of melanoma. METHODS: Four hundred individuals with melanoma and personal or family history of cancers underwent germline testing of >80 cancer predisposition genes. Comparative analysis of germline data was performed on 3 additional oncologic and dermatologic data sets. RESULTS: Germline pathogenic/likely pathogenic (P/LP) variants were identified in 15.3% (61) individuals with melanoma. Most variants (41, 67%) involved genes considered unrelated to melanoma (BLM, BRIP1, CHEK2, MLH1, MSH2, PMS2, RAD51C). A third (20, 33%) were in genes previously associated with familial melanoma (BAP1, BRCA2, CDKN2A, MITF, TP53). Nearly half (30, 46.9%) of P/LP variants were in homologous repair deficiency genes. Validation cohorts demonstrated P/LP rates of 10.6% from an unselected oncologic cohort, 15.8% from a selected commercial testing cohort, and 14.5% from a highly selected dermatologic study. LIMITATIONS: Cohorts with varying degrees of selection, some retrospective. CONCLUSION: Germline predisposition in individuals with melanoma is common, with clinically actionable findings diagnosed in 10.6% to 15.8%.

Cascade testing for hereditary cancer: comprehensive multigene panels identify unexpected actionable findings in relatives.

Current guidelines recommend single variant testing in relatives of patients with known pathogenic or likely pathogenic germline variants in cancer predisposition genes. This approach may preclude the use of risk-reducing strategies in family members who have pathogenic or likely pathogenic germline variants in other cancer predisposition genes. Cascade testing using multigene panels was performed in 3696 relatives of 7433 probands. Unexpected pathogenic or likely pathogenic germline variants were identified in 230 (6.2%) relatives, including 144 who were negative for the familial pathogenic or likely pathogenic variant but positive for a pathogenic or likely pathogenic variant in a different gene than the proband and 74 who tested positive for the familial pathogenic or likely pathogenic variant and had an additional pathogenic or likely pathogenic variant in a different gene than the proband. Of the relatives with unexpected pathogenic or likely pathogenic germline variants, 36.3% would have qualified for different or additional cancer screening recommendations. Limiting cascade testing to only the familial pathogenic or likely pathogenic variant would have resulted in missed, actionable findings for a subset of relatives.

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.

Rate of Pathogenic Germline Variants in Patients With Lung Cancer.

PURPOSE: Germline genetic testing (GGT) is now recommended for all patients diagnosed with ovarian or pancreatic cancer and for a large proportion of patients based solely on a diagnosis of colorectal or breast cancer. However, GGT is not yet recommended for all patients diagnosed with lung cancer (LC), primarily because of a lack of evidence that supports a significant frequency of identifying pathogenic germline variants (PGVs) in these patients. This study characterizes GGT results in a cohort of patients with LC. METHODS: We reviewed deidentified data for 7,788 patients with GGT (2015-2022). PGV frequencies were compared to a control cohort of unaffected individuals. GGT results were stratified by genomic ancestry, history of cancer, and PGV clinical actionability per current guidelines. RESULTS: Of all patients with LC, 14.9% (1,161/7,788) had PGVs. The rate was similar when restricted to patients with no cancer family history (FH) or personal history (PH) of other cancers (14.3%). PGVs were significantly enriched in BRCA2, ATM, CHEK2, BRCA1, and mismatch repair genes compared with controls. Patients of European (EUR) genomic ancestry had the highest PGV rate (18%) and variants of uncertain significance were significantly higher in patients of non-EUR genomic ancestry. Of the PGVs identified, 61.3% were in DNA damage repair (DDR) genes and 95% were clinically actionable. CONCLUSION: This retrospective study shows a LC diagnosis identifies patients with a significant likelihood of having a cancer-predisposing PGV across genomic ancestries. Enrichment of PGVs in DDR genes suggests that these PGVs may contribute to LC cancer predisposition. The frequency of PGVs among patients with LC did not differ significantly according to FH or PH of other cancers.

Clinical and Functional Analyses of an African-ancestry Gain-of-function HOXB13 Variant Implicated in Aggressive Prostate Cancer.

BACKGROUND: Recent reports have uncovered a HOXB13 variant (X285K) predisposing to prostate cancer in men of West African ancestry. The clinical relevance and protein function associated with this inherited variant are unknown. OBJECTIVE: To determine the clinical relevance of HOXB13 (X285K) in comparison with HOXB13 (G84E) and BRCA2 pathogenic/likely pathogenic (P/LP) variants, and to elucidate the oncogenic mechanisms of the X285K protein. DESIGN, SETTING, AND PARTICIPANTS: Real-world data were collected from 21,393 men with prostate cancer undergoing genetic testing from 2019 to 2022, and in vitro cell-line models were established for the evaluation of oncogenic functions associated with the X285K protein. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Genetic testing results were compared among patient groups according to self-reported race/ethnicity, Gleason scores, and American Joint Committee on Cancer stages using the exact test. Oncogenic functions of X285K were evaluated by RNA sequencing, chromatin immunoprecipitation sequencing, and Western blot analyses. RESULTS AND LIMITATIONS: HOXB13 (X285K) was significantly enriched in self-reported Black (1.01%) versus White (0.01%) patients. We observed a trend of more aggressive disease in the HOXB13 (X285K) and BRCA2 P/LP carriers than in the HOXB13 (G84E) carriers. Replacement of the wild-type HOXB13 protein with the X285K protein resulted in a gain of an E2F/MYC signature, validated by the elevated expression of cyclin B1 and c-Myc, without affecting the androgen response signature. Elevated expression of cyclin B1 and c-Myc was explained by enhanced binding of the X285K protein to the promoters and enhancers of these genes. The limitations of the study are the lack of complete clinical outcome data for all patients studied and the use of a single cell line in the functional analysis. CONCLUSIONS: HOXB13 (X285K) is significantly enriched in self-reported Black patients, and X285K carriers detected in the real-world clinical setting have aggressive prostate cancer features similar to the BRCA2 carriers. Functional studies revealed a unique gain-of-function oncogenic mechanism of X285K protein in regulating E2F/MYC signatures. PATIENT SUMMARY: The HOXB13 (X285K) variant is clinically and functionally linked to aggressive prostate cancer, supporting genetic testing for X285K in Black men and early disease screening of carriers of this variant.

Retrospective Cohort Study on the Limitations of Direct-to-Consumer Genetic Screening in Hereditary Breast and Ovarian Cancer.

PURPOSE: Among cancer predisposition genes, most direct-to-consumer (DTC) genetic tests evaluate three Ashkenazi Jewish (AJ) founder mutations in BRCA1/2, which represent a small proportion of pathogenic or likely pathogenic variants (PLPV) in cancer predisposing genes. In this study, we investigate PLPV in BRCA1/2 and other cancer predisposition genes that are missed by testing only AJ founder BRCA1/2 mutations. METHODS: Individuals were referred to genetic testing for personal diagnoses of breast and/or ovarian cancer (clinical cohort) or were self-referred (nonindication-based cohort). There were 348,692 participants in the clinical cohort and 7,636 participants in the nonindication-based cohort. Both cohorts were analyzed for BRCA1/2 AJ founder mutations. Full sequence analysis was done for PLPV in BRCA1/2, CDH1, PALB2, PTEN, STK11, TP53, ATM, BARD1, BRIP1, CHEK2 (truncating variants), EPCAM, MLH1, MSH2/6, NF1, PMS2, RAD51C/D, and 22 other genes. RESULTS: BRCA1/2 AJ founder mutations accounted for 10.8% and 29.7% of BRCA1/2 PLPV in the clinical and nonindication-based cohorts, respectively. AJ founder mutations accounted for 89.9% of BRCA1/2 PLPV in those of full AJ descent, but only 69.6% of those of partial AJ descent. In total, 0.5% of all individuals had a BRCA1/2 AJ founder variant, while 7.7% had PLPV in a high-risk breast/ovarian cancer gene. For non-AJ individuals, limiting evaluation to the AJ founder BRCA1/2 mutations missed >90% of mutations in actionable cancer risk genes. Secondary analysis revealed a false-positive rate of 69% for PLPV outside of non-AJ BRCA 1/2 founder mutations. CONCLUSION: DTC genetic testing misses >90% of BRCA1/2 PLPV in individuals of non-AJ ancestry and about 10% of BRCA1/2 PLPV among AJ individuals. There is a high false-positivity rate for non-AJ BRCA 1/2 PLPV with DTC genetic testing.

Efficacy of National Comprehensive Cancer Network Guidelines in Identifying Pathogenic Germline Variants Among Unselected Patients with Prostate Cancer: The PROCLAIM Trial.

BACKGROUND: Prostate cancer (PCa) patients with pathogenic/likely pathogenic germline variants (PGVs) in cancer predisposition genes may be eligible for U.S. Food and Drug Administration-approved targeted therapies, clinical trials, or enhanced screening. Studies suggest that eligible patients are missing genetics-informed care due to restrictive testing criteria. OBJECTIVE: To establish the prevalence of actionable PGVs among prospectively accrued, unselected PCa patients, stratified by their guideline eligibility. DESIGN, SETTING, AND PARTICIPANTS: Consecutive, unselected PCa patients were enrolled at 15 sites in the USA from October 2019 to August 2021, and had multigene cancer panel testing. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Correlates between the prevalence of PGVs and clinician-reported demographic and clinical characteristics were examined. RESULTS AND LIMITATIONS: Among 958 patients (median [quartiles] age at diagnosis 65 [60, 71] yr), 627 (65%) had low- or intermediate-risk disease (grade group 1, 2, or 3). A total of 77 PGVs in 17 genes were identified in 74 patients (7.7%, 95% confidence interval [CI] 6.2-9.6%). No significant difference was found in the prevalence of PGVs among patients who met the 2019 National Comprehensive Cancer Network Prostate criteria (8.8%, 43/486, 95% CI 6.6-12%) versus those who did not (6.6%, 31/472, 95% CI 4.6-9.2%; odds ratio 1.38, 95% CI 0.85-2.23), indicating that these criteria would miss 42% of patients (31/74, 95% CI 31-53%) with PGVs. The criteria were less effective at predicting PGVs in patients from under-represented populations. Most PGVs (81%, 60/74) were potentially clinically actionable. Limitations include the inability to stratify analyses based on individual ethnicity due to low numbers of non-White patients with PGVs. CONCLUSIONS: Our results indicate that almost half of PCa patients with PGVs are missed by current testing guidelines. Comprehensive germline genetic testing should be offered to all patients with PCa. PATIENT SUMMARY: One in 13 patients with prostate cancer carries an inherited variant that may be actionable for the patient's current care or prevention of future cancer, and could benefit from expanded testing criteria.

Racial disparities in cascade testing for cancer predisposition genes.

We sought to determine whether there are racial disparities in cascade testing rates and whether providing testing at no-charge impacts rates in Black and White at-risk-relatives (ARR). Probands with a pathogenic/likely pathogenic germline variant in a cancer predisposition gene were identified up to one year before and up to one year after cascade testing became no-charge in 2017. Cascade testing rates were measured as the proportion of probands who had at least one ARR obtain genetic testing through one commercial laboratory. Rates were compared between self-reported Black and White probands using logistic regression. Interaction between race and cost (pre/post policy) was tested. Significantly fewer Black probands than White probands had at least one ARR undergo cascade genetic testing (11.9% versus 21.7%, OR 0.49, 95% CI 0.39-0.61, p < 0.0001). This was seen both before (OR 0.38, 95% CI 0.24-0.61, p < 0.001) and after (OR 0.53, 95% CI 0.41-0.68, p < 0.001) the no-charge testing policy. Rates of an ARR undergoing cascade testing were low overall, and significantly lower in Black versus White probands. The magnitude of difference in cascade testing rates between Blacks and Whites did not significantly change with no-charge testing. Barriers to cascade testing in all populations should be explored in order to maximize the benefits of genetic testing for both treatment and prevention of cancer.

Fumarate Hydratase Variants and Their Association With Paraganglioma/Pheochromocytoma.

OBJECTIVE: To clarify the link between germline variants in fumarate hydratase (FH), hereditary leiomyomatosis and renal cell cancer (HLRCC), and paraganglioma (PGL) and pheochromocytoma (PCC) we utilize a well-annotated hereditary cancer testing database. METHODS: Records of 120,061 patients receiving germline testing were obtained. FH variants were classified into 4 categories: autosomal dominant (AD) HLRCC variants, autosomal recessive (AR) fumarase deficiency (FMRD), variants, previously reported as PGL/PCC FH variants, and variants of unknown significance (VUS) not previously associated with PGL/PCC (NPP-VUS). Rates of PGL/PCC were compared with those with negative genetic testing. RESULTS: About 1.3% of individuals carried FH variants which were more common among individuals with PGL/PCC compared to those without (3.1% vs 1.3%, P < .0001). PGL/PCC rates were higher among individuals with PGL/PCC FH variants compared to those with negative genetic testing (22.2% vs 0.9%, P < .0001). Neither AD HLRCC variants (0.3% vs 0.9%, P = .35) nor AR FMRD variants (1.4% vs 0.9%, P = .19) carried an increased prevalence of PGL/PCC. An increased prevalence of PGL/PCC was detected in those with NPP-VUS (2.0% vs 0.9%, P = .0023). CONCLUSIONS: Certain FH variants confer an increased risk of PGL/PCC, but not necessarily HLRCC. While universal screening for PGL/PCC among all individuals with FH variants does not appear warranted, it should be considered in select high-risk PGL/PCC FH variants.

Prevalence and clinical implications of germline mutations among Jordanian patients with ovarian cancer. The Jordanian exploratory cancer genetics (Jo-ECAG) ovarian study.

BACKGROUND: Ovarian cancer is one of the most common gynecological malignancies. Due to the absence of effective screening methods, ovarian cancer is usually diagnosed at late stages. Patients with pathogenic and likely-pathogenic germline variants (PGVs) in BRCA1 or BRCA2 harbor elevated risk of developing both ovarian and breast cancers. Identifying PGVs may help in both cancer prevention and active disease treatment. Worldwide prevalence of PGVs varies and the matter is poorly addressed among Arab patients. METHODS: Patients with epithelial ovarian, fallopian tube or primary peritoneal cancers were offered the universal 20 or 84-multi-gene panel testing as per standard guidelines. Cascade family screening was also offered to all first and second-degree relatives of PGV positive patients. Genetic testing was done at a referral lab using a next generation sequencing (NGS)-based platform. RESULTS: During the study period, 152 patients, median age (range): 50 (18-79) years old, were tested. The majority (n = 100, 65.8%) had high-grade serous carcinoma, and 106 patients (69.7%) had metastatic disease at presentation. In total, 38 (25.0%) had PGVs, while 47 (30.9%) others had variants of uncertain significance (VUS). PGVs were mostly in BRCA1 (n = 21, 13.8%) and in BRCA2 (n = 12, 7.9%), while 6 (3.9%) others had PGVs in non-BRCA1/2 genes. PGV rates were significantly higher among 15 patients with a positive family history of ovarian cancer (60.0%, p = .022) and among 52 patients with a positive family history of breast cancer (40.4%, p = .017). CONCLUSIONS: PGVs are common among Jordanian women with ovarian cancer, and mostly occur in BRCA1/2. Given its clinical impact on disease prevention and precision therapy, universal testing should be routinely offered.

Ashkenazi Jewish and Other White APC I1307K Carriers Are at Higher Risk for Multiple Cancers.

Purpose: APC I1307K has a higher prevalence among Ashkenazi Jews (AJ), and a two-fold increased risk for colorectal cancer (CRC) compared to non-Jewish populations. We assessed CRC and extracolonic malignancies among I1307K carriers from AJ and non-AJ whites (NAW). Methods: We compared the rate of I1307K in cancer patients who underwent germline genetic testing via a multi-gene panel with healthy subjects retrieved from the gnomAD database. Cases undergoing testing were not selected and testing was undertaken through a commercial laboratory. Results: Overall, 586/7624 (7.6%) AJ with cancer carried I1307K compared to 342/4918 (6.9%) in the AJ control group (p = NS). In the NAW, 318/141,673 (0.2%) cancer patients and 73/58,918 (0.1%) controls carried the variant [OR = 1.8, (95% CI 1.41−2.35), p < 0.001]. I1307K in NAW was associated with an increased risk of CRC [OR = 1.95, (95% CI 1.39−2.73), p < 0.01], melanoma [OR = 2.54, (95% CI 1.57−3.98)], breast [females, OR = 1.73, (95% CI 1.18−2.65), p < 0.01], and prostate cancer [males, OR = 2.42, (95% CI 1.45−3.94), p < 0.01]. Among AJ, the variant increased the risk for CRC [OR = 1.67, (95% CI 1.36−2.05), p < 0.001] and renal cancer [OR = 1.64, (95% CI 1.04−2.47)]. AJ men had a higher risk for any cancer [OR = 1.32, (95% CI 1.05−1.66), p < 0.05] and melanoma [OR = 2.04, (95% CI 1.24−3.22); p < 0.05]. Conclusions: This is the most extensive study to date conducted on I1307K carriers, although it is amenable to selection bias. NAW carrying I1307K had a higher risk of any cancer and several specific cancer types, whereas AJ carrying the variant had a risk for only a few select cancers. Our data add to the research base on I1307 carriers concerning future risk management.

Multigene Panel Testing Yields High Rates of Clinically Actionable Variants Among Patients With Colorectal Cancer.

PURPOSE: Whether germline multigene panel testing (MGPT) should be performed in all individuals with colorectal cancer (CRC) remains uncertain. Therefore, we aimed to determine the yield and potential clinical impact of MGPT across a large, diverse CRC cohort. METHODS: This was a retrospective cohort study of adults with CRC who underwent MGPT of > 10 genes at a commercial laboratory between March 2015 and May 2021. All data were prospectively collected through a single commercial laboratory and retrospectively analyzed. RESULTS: A total of 34,244 individuals with a history of CRC underwent germline MPGT and were included in the analysis. This cohort was predominantly female (60.7%), White (70.6%), and age 50 years or older (68.9%), with 35.5% also reporting a noncolorectal malignancy. At least one pathogenic/likely pathogenic germline variant (PGV) was found in 4,864 (14.2%), with 3,111 (9.1%) having a PGV associated with increased CRC/polyposis risk and 1,048 (3.1%) having an otherwise clinically actionable PGV. Larger gene panels were not clearly associated with higher yield of clinically actionable PGVs. PGVs were more prevalent in individuals of Ashkenazi Jewish descent (P < .001) and Hispanic ethnicity (P < .001). Across all ages, panel sizes, and races/ethnicities, the rate of clinically actionable PGVs on MGPT was 7.9% or greater. A variant of uncertain significance was identified in 13,094 individuals (38.2%). Identification of a variant of uncertain significance associated with panel size (P < .001) and was lower in individuals of Ashkenazi Jewish descent (P < .001), but higher in Black, Asian, and Hispanic individuals (P < .001). CONCLUSION: To our knowledge, this is the largest study to date examining MGPT in CRC, demonstrating high rates of clinically actionable variants detected across all age groups, panel sizes, and racial/ethnic groups. This work supports consideration of broadening germline genetic testing criteria for individuals with CRC.

Comparison of Germline Genetic Testing Before and After a Medical Policy Covering Universal Testing Among Patients With Colorectal Cancer.

Importance: In 2020, some health insurance plans updated their medical policy to cover germline genetic testing for all patients diagnosed with colorectal cancer (CRC). Guidelines for universal tumor screening via microsatellite instability and/or immunohistochemistry (MSI/IHC) for mismatch repair protein expression for patients with CRC have been in place since 2009. Objectives: To examine whether uptake of MSI/IHC screening and germline genetic testing in patients with CRC has improved under these policies and to identify actionable findings and management implications for patients referred for germline genetic testing. Design, Setting, and Participants: The multicenter, retrospective cohort study comprised 2 analyses of patients 18 years or older who were diagnosed with CRC between January 1, 2017, and December 31, 2020. The first analysis used an insurance claims data set to examine use of MSI/IHC screening and germline genetic testing for patients diagnosed with CRC between 2017 and 2020 and treated with systemic therapy. The second comprised patients with CRC who had germline genetic testing performed in 2020 that was billed under a universal testing policy. Main Outcomes and Measures: Patient demographic characteristics, clinical information, and use of MSI/IHC screening and germline genetic testing were analyzed. Results: For 9066 patients with newly diagnosed CRC (mean [SD] age, 64.2 [12.7] years; 4964 [54.8%] male), administrative claims data indicated that MSI/IHC was performed in 6645 eligible patients (73.3%) during the study period, with 2288 (25.2%) not receiving MSI/IHC despite being eligible for coverage. Analysis of a second cohort of 55 595 patients with CRC diagnosed in 2020 and covered by insurance found that only 1675 (3.0%) received germline genetic testing. In a subset of patients for whom germline genetic testing results were available, 1 in 6 patients had pathogenic or likely pathogenic variants, with most of these patients having variants with established clinical actionability. Conclusions and Relevance: This nationwide cohort study found suboptimal rates of MSI/IHC screening and germline genetic testing uptake, resulting in clinically actionable genetic data being unavailable to patients diagnosed with CRC, despite universal eligibility. Effective strategies are required to address barriers to implementation of evidence-based universal testing policies that support precision treatment and optimal care management for patients with CRC.

68Ga-DOTATATE Avid Metastatic Vertebral Renal Cell Carcinoma in the Setting of von Hippel-Lindau Syndrome.

Although rare, a metastatic renal cell carcinoma could present with 68Ga-DOTATATE avidity. A 66-year-old man with von Hippel-Lindau syndrome (VHL) presented with 68Ga-DOTATATE uptake in the pancreatic head, splenic hilar region, and multiple osseous sites, including the right lateral portion of the T9 vertebrae. Biopsy of the T9 lesion confirmed metastatic renal cell carcinoma. Various VHL-associated cancers may display 68Ga-DOTATATE avidity, which can change and guide clinical decisions for the patient.

Cancer risks associated with heterozygous ATM loss of function and missense pathogenic variants based on multigene panel analysis.

PURPOSE: Cancer risks conferred by germline, heterozygous, ATM pathogenic/likely pathogenic variants (PSVs) are yet to be consistently determined. The current study assessed these risks by analysis of a large dataset of ATM heterozygote loss of function (LOF) and missense PSV carriers tested with a multigene panel (MGP). METHODS: De-identified data of all individuals who underwent ATM sequencing as part of MGP between October 2015 and February 2020 were reviewed. In cancer cases, rates for the six most prevalent variants and for all LOF and missense PSV combined were compared with rates of the same PSV in ethnically matched, healthy population controls. Statistical analysis included Chi-square tests and odds ratios calculations. RESULTS: For female breast cancer cases, LOF )1794/219,269) and missense (301/219,269) ATM PSVs were seen at higher rates compared to gnomAD non-cancer controls (n = 157/56,001 and n = 27/61,208; p < 0.00001, respectively). Notably, the rate of the c.103C > T variant was higher in controls than in breast cancer cases [p = 0.001; OR 0.31 (95% CI 0.1-0.6)]. For all cancer cases combined, compared with non-cancer population controls, LOF (n = 143) and missense (n = 15) PSVs reported in both datasets were significantly more prevalent in cancer cases [ORLOF 1.7 (95% 1.5-1.9) ORmissense 3.0 (95% CI 2.3-4); p = 0.0001]. CONCLUSION: Both LOF and missense heterozygous ATM PSVs are more frequently detected in cases of several cancer types (breast, ovarian, prostate, lung, pancreatic) compared with healthy population controls. However, not all ATM PSVs confer an increased cancer risk (e.g., breast).