Riegert‐Johnson, Douglas L.

Abstract BACKGROUND Von Hippel-Lindau (VHL) disease is a hereditary cancer syndrome characterized by development of multiple neoplasms, including central nervous system (CNS) hemangioblastomas, renal cell carcinoma (RCC), pancreatic neuroendocrine tumors (pNETs), and retinal hemangioblastomas. Belzutifan, a hypoxia-inducible factor 2-alpha (HIF-2α) inhibitor, has demonstrated efficacy in treating VHL-associated tumors. This study evaluates our institutional experience with belzutifan in patients with VHL-related tumors. MATERIAL AND METHODS We conducted a retrospective cohort study across three Mayo Clinic sites, including patients aged ≥18 years with genetically confirmed VHL disease who received belzutifan between October 2021 and March 2025. Clinical/radiological data, and adverse events (AEs) were extracted from electronic health records. Tumor responses were assessed using RECIST v1.1 criteria for RCC, pNET, CNS hemangioblastoma. Retinal hemangioblastoma responses were evaluated through ophthalmologic assessments. RESULTS Forty-five patients were included (median age 44 58% female). Sixty-seven percent had RCC, 91% had CNS hemangioblastomas, 53% had pNETs, and 62% had retinal hemangioblastomas. The median duration of belzutifan therapy was 22.6 months (range 1.0-41.4 months). Among patients with RCC (n=26), overall response rate (ORR) was 19% and median time to best response (MTBR) was 7.4 months. Five patients had partial response (PR), 15 had stable disease (SD), and 1 had progressive disease (PD). For CNS hemangioblastomas (n=41), ORR was 12%, MTBR was 6.2 months. 5 patients had PR, 30 had SD, and none had PD. For pNET (n=17), ORR was 41%, MTBR was 8.2 months. One patient had CR, 6 patients had PR, 6 had SD, none had PD. For retinal hemangioblastomas (n=28), 6 (21%) showed improvement, 9 (32%) remained stable, and 3 (11%) showed progression. MTBR was 6.7 months. Treatment-related AEs occurred in 98% of patients. Common AEs included anemia (89%), fatigue (80%), hypoxia (18%), and headache (13%). Grade 3 AEs were observed in 20% of patients, including anemia (7%), hypoxia (9%), fatigue (4%), pneumonitis (2%), loss of consciousness (2%). One patient experienced a grade 4 event (status epilepticus). Anemia management involved iron supplementation (n=11), RBC transfusion (n=3), dose reduction (n=2), treatment holiday (n=8), permanent discontinuation (n=1). Hypoxia management included dose reduction (n=1), treatment holiday (n=3), discontinuation (n=1). CONCLUSION Belzutifan shows clinical activity across various VHL-associated neoplasms in real-world practice, with a manageable safety profile. The lower ORR compared to the phase III trial may reflect differences in baseline disease, including lower tumor burden in our cohort. These findings support its continued use in VHL disease, with attention to monitoring and managing treatment-related AEs.

PURPOSE Guidelines recommend germline genetic testing (GT) for patients with pancreatic ductal adenocarcinoma (PDAC). This study aims to evaluate the utilization and outcomes of multigene panel GT in patients with PDAC. METHODS This retrospective, multisite study included patients with PDAC diagnosed between May 2018 and August 2020 at Mayo Clinic Arizona, Florida, and Minnesota. Discussion, uptake, and outcomes of GT were compared before (May 1, 2018-May 1, 2019) and after (August 1, 2019-August 1, 2020) the guideline update, accounting for a transition period. RESULTS The study identified 533 patients with PDAC, with 321 (60.2%) preguideline and 212 (39.8%) postguideline. Patient characteristics did not differ between the preguideline and postguideline periods. GT was discussed in 34.3% (110 of 321) of preguideline and 39.6% (84 of 212) of postguideline patients (odds ratio [OR], 1.26 [95% CI, 0.88 to 1.80]) and subsequently performed in 80.9% (89 of 110) of preguideline and 75.0% (63 of 84) of postguideline patients (OR, 1.10 [95% CI, 0.75 to 1.61]). Of 152 tested patients, 26 (17.1%) had a pathogenic variant (PV), of whom 17 (11.2%; 17 of 152) were PDAC-associated. Over the entire study period, GT was more likely in younger patients (65 v 70 years; P < .001), those seen by a medical oncologist (82.9% v 69.0%; P < .001), and those surviving more than 12 months from diagnosis (70.4% v 43.4%; P < .001). Demographics and personal/family cancer history were comparable between patients with and without a PDAC PV. CONCLUSION GT remains underutilized despite National Comprehensive Cancer Network guideline recommendations. Given the poor prognosis of PDAC and potential implications of GT, efforts to increase utilization are needed to provide surveillance and support to both patients with PDAC and at-risk family members.

Prognosis is generally poor for patients with pancreatic ductal adenocarcinoma. However, patients with germline BRCA1 or BRCA2 mutations (gBRCAm) may benefit from first-line platinum-based chemotherapy and maintenance therapy with the poly(adenosine diphosphate-ribose) polymerase inhibitor olaparib following at least 16 weeks of first-line platinum-based chemotherapy without disease progression. Germline breast cancer gene (BRCA) testing is therefore important to ensure that patients receive the most effective treatment. In addition, testing for other DNA damage response gene mutations beyond gBRCAm may also guide treatment decisions. However, clinical pathways for genetic testing are often suboptimal, leading to delays in treatment initiation or missed opportunities for personalized therapy. Barriers to testing include low rates of referral and uptake, delays to referral and slow result turnaround times, cost, and biopsy and assay limitations if somatic testing is performed, leading to the requirement for subsequent dedicated germline testing. Low rates of referral may result from lack of awareness among physicians of the clinical value of testing, coupled with low confidence in interpreting test results and poor availability of genetic counseling services. Among patients, barriers to uptake may include similar lack of awareness of the clinical value of testing, anxiety regarding the implications of test results, lack of insurance coverage, fear of negative insurance implications, and socioeconomic factors. Potential solutions include innovative approaches to testing pathways, including ‘mainstreaming’ of testing in which BRCA tests are routinely arranged by the treating oncologist, with the involvement of genetic counselors if a patient is found to have a gBRCAm. More recently, the utility of multigene panel analyses has also been explored. Access to genetic counseling may also be improved through initiatives such as having a genetic counseling appointment for all new patient visits and telemedicine approaches, including the use of telephone consultations or DVD-assisted counseling. Educational programs will also be beneficial, and cost effectiveness is likely to improve as the number of targeted treatments increases and when the earlier detection of tumors in family members following cascade testing is considered.

AbstractBackgroundPathogenic variants in AXIN2 have been associated with tooth agenesis, colon polyps, and colon cancer. Given the rare nature of this phenotype, we set out to collect additional genotypic and phenotypic information.MethodsData were collected via a structured questionnaire. Sequencing was performed in these patients mostly due to diagnostic purpose. A little more than half of the AXIN2 variant carriers were identified by NGS; other six were family members.ResultsHere, we report 13 individuals with a heterozygous AXIN2 pathogenic/likely pathogenic variant who have a variable expression of oligodontia‐colorectal cancer syndrome (OMIM 608615) or oligodontia‐cancer predisposition syndrome (ORPHA 300576). Three individuals from one family also had cleft palate, which might represent a new clinical feature of AXIN2 phenotype, also given the fact that AXIN2 polymorphisms have been found in association with oral clefting in population studies. AXIN2 has already been added to multigene cancer panel tests; further research should be conducted to determine whether it should be added to cleft lip/palate multigene panels.ConclusionMore clarity about oligodontia‐colorectal cancer syndrome, about the variable expression, and associated cancer risks is needed to improve clinical management and to establish guidelines for surveillance. We collected information about the surveillance that was advised, which might support clinical management of these patients.

688 Background: Guidelines recommend patients with pancreatic ductal adenocarcinoma (PDAC) undergo genetic testing for germline pathogenic variants (PV). The aim of this study was to evaluate compliance with recently updated guidelines (May 2019) and assess subsequent uptake and outcomes of genetic testing in PDAC patients. In addition, social and clinical factors associated with genetic testing were assessed. Methods: A retrospective chart review of patients diagnosed with PDAC between May 2018 and August 2020 was performed. Discussion and subsequent uptake of genetic testing was reviewed and compared between a 12-month period before (pre-guideline) and a 12-month period after (post-guideline) guidelines were updated, accounting for a three-month transition period. Univariate and multivariate logistic regression analysis was used to assess factors predictive of undergoing genetic testing. Results: In total, 534 patients with PDAC were identified; 321 (60.1%) in the pre-guideline period and 213 (39.9%) in the post-guideline period. The mean age at diagnosis was 68 years and 47% were female. Genetic testing was discussed in 34% (109/321) of pre-guideline and in 39% (84/213) of post-guideline patients ( P = .23). Of those, 82% (89/109) of patients in pre-guideline and 75% (63/84) in post-guideline groups underwent subsequent genetic testing ( P = .71). In 26 (17.1%) of 152 tested patients, a PV was identified, of which 17 (11.2%; 17/152) had a PDAC-associated PV. Age, cancer stage at diagnosis, length of survival, and having a first-degree relative with pancreatic cancer were significant predictors of genetic testing on multivariate analysis. Conclusions: Adherence to recently updated guidelines is poor and germline genetic testing in PDAC patients remains insufficient. Efforts to increase awareness of benefits of testing, which include personalized therapies for patients and cascade testing in family members for subsequent enrollment in pancreatic cancer surveillance programs, could improve future uptake.[Table: see text]

AbstractAdvances have dated the genetic testing initially offered to evaluate for hereditary breast and ovarian cancer risks. Previous research has demonstrated that many patients have not updated testing. This study reviewed the incidence of additional analysis after an uninformative BRCA1/2 result and offered updated testing with limited barriers to those who had not completed. After viewing an educational video and providing informed consent, eligible patients were mailed a saliva collection kit to complete an 84‐gene hereditary cancer panel at no personal cost. A total of 704 patients had completed BRCA1/2 only testing between 2001 and 2020. Fifteen percent (N = 102) of the 671 patients with an uninformative BRCA1/2 result had already completed expanded testing. Most, 74 of 102 (73%), had been rereferred to medical genetics during a clinical visit related to cancer care. Those who had already completed additional testing were more likely to have a personal history of cancer (92% vs. 79%, p = 0.002) and live locally (p = 0.032). Invitation to complete updated testing through this study was sent to 372 people, and 116 (31%) consented to participate. For 142 of the 256 who did not proceed with testing through the study, proof of receipt of research information was available. In total, 22 pathogenic variants were reported in 21 of the 226 patients with updated testing from before and including our study: ATM (4), CHEK2 (4), LZTR1 (1), MUTYH (3), NBN (1), NF1 (1), NTHL1 (1), PALB2 (4), PMS2 (1), RAD50 (1), and SPINK1 (1). Many potential barriers of retesting were eliminated by removing personal costs or travel requirements. Still, only about 30% of patients agreed to participate, and a significant portion elected not to proceed. Future research could focus on the discovery of other factors that dissuade patients and what measures may better inform them on potential benefits.

INTRODUCTION: To report the prevalence and outcomes of unselected pancreatic cancer (PC) patients with pathogenic/likely pathogenic germline variants (PGVs) detected using a universal testing approach. METHODS: We undertook a prospective, multisite study of germline sequencing using a >80 gene next-generation sequencing platform among 250 patients with PC (not selected for age or family history of cancer) between April 1, 2018, and March 31, 2020. Demographic, tumor characteristics, and clinical outcomes were compared between PGV carriers and noncarriers. RESULTS: Of 250 patients, the mean age was 65 years (SD 8.7), 56% was male, 83.6% was White, and 65.6% had advanced disease (stages III and IV). PGVs were found in 15.2% (N = 38) of patients, and 2 patients had more than 1 PGV. Variants of uncertain significance were found in 44.4% (N = 111). Family history of cancer (odds ratio: 2.36, 95% confidence interval: 1.14–5.19, P = 0.025) was associated with a higher risk of PGV. In a median follow-up of 16.5 months, the median overall survival was 16.8 months in PGV carriers compared with 16.5 months in noncarriers (hazard ratio: 0.51, 95% confidence interval: 0.25–1.01, P = 0.05). Higher levels of carbohydrate antigen 19-9 and advanced disease stages (III and IV) were associated with worse outcomes in both groups. Overall, 68% of PGV carriers had mutations in homologous recombination repair genes, including BRCA1 , BRCA2 , PALB2 , ATM , CHEK2 , NBN , and RAD51C . DISCUSSION: Universal multigene panel testing in PC reveals that 1 in 6 patients are carriers of PGV. Multigene germline testing should be used to aid in treatment selection, prognostication, and familial cancer counseling.

4118 Background: Germline variations in cancer susceptibility genes have important implications on treatment and family counseling in pancreatic cancer (PC). We report the prevalence and clinical outcomes of unselected PC patients with pathogenic germline variants (PGV) detected using a universal testing approach. Methods: We undertook a prospective multi-site study of germline sequencing using an >80 gene next-generation sequencing platform among 250 PC patients (not selected for age or family cancer history) between April 1, 2018 and March 31, 2020. Demographic, tumor characteristics and clinical outcomes were compared between PGV carriers and non-carriers. Results: Of 250 patients, the mean age was 65 years (SD 8.7), 56% were male, 83.6% were white and 65.6% had advanced disease (Stage III and IV). PGV were found in 15.2% (N=38) of patients, two patients had more than one PGV. Variants of uncertain significance were found in 44.4% (N=111). Family history of cancer (OR 2.36, 95% CI: 1.14-5.19, p=0.025) was associated with a higher risk of PGV. In a median follow up of 16.5 months, median overall survival was 16.8 months in PGV carriers compared with 16.5 months in non-carriers (HR 0.51, 95 %CI, 0.25-1.01, p=0.05). Higher levels of CA 19-9 and advanced stages (III and IV) were associated with worse outcomes in both groups. Overall, 68% of PGV carriers had mutations in homologous recombination repair (HRR) genes, including BRCA1, BRCA2, PALB2, ATM, CHEK2, NBN, RAD51C. In 65% of HRR gene carrier’s systemic therapy with platinum was used. Conclusions: Universal multi-gene panel testing in pancreatic cancer reveals that 1 in 6 patients are carriers of PGV and is associated with improved survival. Multi-gene germline testing should be used to aid in treatment selection, prognostication, and familial cancer counseling. Distribution of the 40 PGV by penetrance status.[Table: see text]

Abstract Background: Hereditary factors play a key role in the risk of developing breast cancers. Identification of a germline predisposition can have important implications for treatment decisions, risk-reducing interventions, cancer screening, and testing for family members. Aim: To determine the prevalence of pathogenic or likely pathogenic germline mutations (P/LP) using a “universal” testing approach and uptake of no-cost cascade family testing in patients with breast cancer. Methods: We undertook a prospective multi-site study of germline genetic alterations among breast cancer patients receiving care at Mayo Clinic cancer centers in Rochester, MN; Eau Claire, WI; Jacksonville, FL and Phoenix, AZ between April 1, 2018 and March 31, 2020. Patients with a new or active breast cancer diagnosis (all stages) irrespective of cancer family history were tested with a &gt;80-gene next generation sequencing panel.Results: Of 390 patients, the median age was 58 years (SD 12.3), 1% were male, 85% were white and 28% had advanced (stage 3-4) disease. P/LP were found in 12.1% (n=47) of patients, including 29 in moderate and high penetrance cancer susceptibility genes. 13 (3.3%) patients had mutations in BRCA1 or 2, while 33 (8.4%) had mutations in BRCAness (ATM, BAP1, BARD1, BLM, BRCA1, BRCA2, BRIP1, CHEK2, NBN, PALB2, RAD50, RAD51C, RAD51D, WRN) associated genes. Of the P/LP findings the most frequent aberrations were in BRCA2 (13.5%), BRCA1 (11.5%), CHEK2 (11.5%), MUTYH (11.5%), and WRN (9.6%). Variants of uncertain significance were found in 209 (53.6%) including 26 (6.6%) with concurrent P/LP and VUS. 37 (9.4%) patients had mutations associated with published management recommendations, precision therapies and/or clinical trial eligibility. 10 (2.6%) patients had P/LP that would not have met current screening guidelines, including 4 with moderate or high penetrance mutations. Patients with younger age of diagnosis were less likely than patients with older age of diagnosis to have a P/LP mutation (OR= 0.47, 95%CI: 0.25-0.90 p = 0.020). Only 10 (21%) patients with P/LP had family members undergo familial site- specific testing at no cost.Conclusions: In this prospective multi-center study of unselected breast cancer patients, universal multi-gene panel testing found that 1 in 8 patients harbor P/LP germline variants. Current guidelines were able to identify the majority of patients with P/LP mutations. Familial site specific testing is greatly under-utilized even when cost is not a barrier. Multigene panels impact cancer patient care by identifying precision medicine treatment interventions, and guiding long-term medical management and preventive surveillance. Citation Format: Brenda Ernst, Natalie Ertz-Archambault, Deborah J Rhodes, Donald W Northfelt, Myra Wick, Douglas L Riegert-Johnson, Scott Okuno, Katie Kunze, Michael Golafshar, Cindy M Azevedo, PLS Uson Junior, ED Esplin, Robert Nussbaum, Margaret Klint, Sarah Mantia, Megan Hager, Keith Stewart, Niloy Jewel Samadder. Universal genetic testing in breast cancer patients: A multi-center prospective study [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD10-05.