Germline genetic regulation of the colorectal tumor immune microenvironment.

OBJECTIVE: To evaluate the contribution of germline genetics to regulating the briskness and diversity of T cell responses in CRC, we conducted a genome-wide association study to examine the associations between germline genetic variation and quantitative measures of T cell landscapes in 2,876 colorectal tumors from participants in the Molecular Epidemiology of Colorectal Cancer Study (MECC). METHODS: Germline DNA samples were genotyped and imputed using genome-wide arrays. Tumor DNA samples were extracted from paraffin blocks, and T cell receptor clonality and abundance were quantified by immunoSEQ (Adaptive Biotechnologies, Seattle, WA). Tumor infiltrating lymphocytes per high powered field (TILs/hpf) were scored by a gastrointestinal pathologist. Regression models were used to evaluate the associations between each variant and the three T-cell features, adjusting for sex, age, genotyping platform, and global ancestry. Three independent datasets were used for replication. RESULTS: We identified a SNP (rs4918567) near RBM20 associated with clonality at a genome-wide significant threshold of 5 × 10- 8, with a consistent direction of association in both discovery and replication datasets. Expression quantitative trait (eQTL) analyses and in silico functional annotation for these loci provided insights into potential functional roles, including a statistically significant eQTL between the T allele at rs4918567 and higher expression of ADRA2A (P = 0.012) in healthy colon mucosa. CONCLUSIONS: Our study suggests that germline genetic variation is associated with the quantity and diversity of adaptive immune responses in CRC. Further studies are warranted to replicate these findings in additional samples and to investigate functional genomic mechanisms.

Validation of Quality Assessment Measures for Inpatient Gastroenterology Consults on Oncologic Patients in Non-teaching Services at a Cancer Center: A Cross-Sectional Study.

OBJECTIVE: To develop and validate tools for measuring inpatient gastroenterology (GI) consultation quality on oncologic patients. METHODS: A total of 145 inpatient GI consults were analyzed using electronic health records in this cross-sectional study. Essential Consult Elements on oncologic-hospitalized patients (EE-COH) and Hospitalized Oncologic Patients Enhanced Quality of Consult Assessment Tool (HOPE-QCAT) were used for grading. Interrater reliability was assessed. RESULTS: Both EE-COH and HOPE-QCAT showed near-perfect interrater reliability across most measures in the validation cohort. On application of these measures for quality assessment, basic evaluation by the requesting hospitalist was partially complete in 24.8%, the request for GI consultation was inappropriate in 18.6%, while the rationale for recommended studies from the GI consultant was provided in 55.7% of cases suggesting key areas for quality improvement. CONCLUSION: We developed highly reliable quality measures for inpatient GI consults on oncology patients. The EE-COH and HOPE-QCAT tools can be utilized in future studies of inpatient GI consult quality and to form the basis for interventions to improve communication between consultants and hospitalists. Such tools could be adapted for inpatient quality assessment across other specialties and settings.

Family communication of cancer genetic test results in an ethnically diverse population: a qualitative exploration of more than 200 patients.

Previous research on family communication of cancer genetic test results has primarily focused on non-Hispanic White patients with high-risk pathogenic variants (PV). There are limited data on patient communication of moderate-risk PVs, variants of uncertain significance (VUS), and negative results. This qualitative study examined communication of positive, negative, and VUS hereditary cancer multi-gene panel (MGP) results in an ethnically and socioeconomically diverse population. As part of a multicenter, prospective cohort study of 2000 patients who underwent MGP testing at three hospitals in California, USA, free-text written survey responses to the question: "Feel free to share any thoughts or experiences with discussing genetic test results with others" were collected from participant questionnaires administered at 3 and 12-months post results disclosure. Content and thematic analyses were performed using a theory-driven analysis, Theory of Planned Behavior (TPB), on 256 responses from 214 respondents. Respondents with high perceived utility of sharing genetic test results often reported positive attitudes towards sharing test results and direct encouragement for genetic testing of others. Respondents with high self-efficacy in the sharing process were likely to report high perceived utility of sharing, whereas patients with low self-efficacy more often had VUS results and were more likely to report uncertainty about sharing. Consistent with TPB, our findings suggest that clinician reinforcement of the utility of genetic testing may increase intent for patients to communicate genetic information. Our findings suggest that clinicians should focus on strategies to improve patient understanding of VUS results.

Selection of Germline Genetic Testing Panels in Patients With Cancer: ASCO Guideline.

PURPOSE: To guide use of multigene panels for germline genetic testing for patients with cancer. METHODS: An ASCO Expert Panel convened to develop recommendations on the basis of a systematic review of guidelines, consensus statements, and studies of germline and somatic genetic testing. RESULTS: Fifty-two guidelines and consensus statements met eligibility criteria for the primary search; 14 studies were identified for Clinical Question 4. RECOMMENDATIONS: Patients should have a family history taken and recorded that includes details of cancers in first- and second-degree relatives and the patient's ethnicity. When more than one gene is relevant based on personal and/or family history, multigene panel testing should be offered. When considering what genes to include in the panel, the minimal panel should include the more strongly recommended genes from Table 1 and may include those less strongly recommended. A broader panel may be ordered when the potential benefits are clearly identified, and the potential harms from uncertain results should be mitigated. Patients who meet criteria for germline genetic testing should be offered germline testing regardless of results from tumor testing. Patients who would not normally be offered germline genetic testing based on personal and/or family history criteria but who have a pathogenic or likely pathogenic variant identified by tumor testing in a gene listed in Table 2 under the outlined circumstances should be offered germline testing.Additional information is available at www.asco.org/molecular-testing-and-biomarkers-guidelines.

Differences in Tumor-Associated T cell receptor repertoires between Early-Onset and Average-Onset colorectal cancer.

The incidence of colorectal cancer (CRC) among individuals younger than age 50 (early onset CRC; EOCRC) has substantially increased, yet the etiology and molecular mechanisms underlying this alarming rise remain unclear. We compared tumor-associated T cell repertoires between EOCRC and average-onset CRC (AOCRC) to uncover potentially unique immune microenvironment-related features by age of onset. Our discovery cohort included 242 patients who underwent surgical resection at Cleveland Clinic from 2000 to 2020. EOCRC was defined as age < 50 years at diagnosis (N = 126), and AOCRC as age ≥ 60 years (N = 116). T cell receptor (TCR) abundance and clonality were measured by immunosequencing of tumors. Logistic regression models were used to evaluate the associations between TCR repertoire features and age of onset, adjusting for sex, race, tumor location, and stage. Findings were replicated in 152 EOCRC and 1,984 AOCRC cases from the Molecular Epidemiology of Colorectal Cancer Study. EOCRC tumors had significantly higher TCR diversity compared to AOCRC tumors in the discovery cohort (Odds Ratio (OR):0.44, 95% Confidence Interval (CI):0.32-0.61, p < .0001). This association was also observed in the replication cohort (OR : 0.74, 95% CI : 0.62-0.89, p = .0013). No significant differences in TCR abundance were observed between EOCRC and AOCRC in either cohort. Higher TCR diversity, suggesting a more diverse intratumoral T cell response, is more frequently observed in EOCRC than AOCRC. Further studies are warranted to investigate the role of T cell diversity and the adaptive immune response more broadly in the etiology and outcomes of EOCRC.