A Prospective Six Sigma Quality Improvement Trial to Optimize Universal Screening for Genetic Syndrome Among Patients With Young-Onset Colorectal Cancer

Clinicopathologic Profile and Treatment Outcomes of Colorectal Cancer in Young Adults: A Multicenter Study From India

PURPOSE

Colorectal cancer (CRC) in young adults is a rising concern in developing countries such as India. This study investigates clinicopathologic profiles, treatment patterns, and outcomes of CRC in young adults, focusing on adolescent and young adult (AYA) CRC in a low- and middle-income country (LMIC).

METHODS

A retrospective registry study from January 2018 to December 2020 involved 126 young adults (age 40 years and younger) with CRC. Patient demographics, clinical features, tumor characteristics, treatment modalities, and survival outcomes were analyzed after obtaining institutional ethics committees' approval.

RESULTS

Among 126 AYA patients, 62.70% had colon cancer and 37.30% had rectal cancer. Most patients (67%) were age 30-39 years, with no significant gender predisposition. Females had higher metastatic burden. Abdominal pain with obstruction features was common. Adenocarcinoma (65%) with signet ring differentiation (26%) suggested aggressive behavior. Limited access to molecular testing hindered mutation identification. Capecitabine-based chemotherapy was favored because of logistical constraints. Adjuvant therapy showed comparable recurrence-free survival in young adults and older patients. For localized colon cancer, the 2-year median progression-free survival was 74%, and for localized rectal cancer, it was 18 months. Palliative therapy resulted in a median overall survival of 33 months (95% CI, 18 to 47). Limited access to targeted agents affected treatment options, with only 27.5% of patients with metastatic disease receiving them. Chemotherapy was generally well tolerated, with hematologic side effect being most common.

CONCLUSION

This collaborative study in an LMIC offers crucial insights into CRC in AYA patients in India. Differences in disease characteristics, treatment patterns, and limited access to targeted agents highlight the need for further research and resource allocation to improve outcomes in this population.

Germline Cancer Risk Profiles of Patients With Young-Onset Colorectal Cancer: Findings From a Prospective Universal Germline Testing and Telegenetics Program

BACKGROUND

Colorectal cancer is being increasingly diagnosed in people younger than 50 years. An inheritable cancer predisposition has been reported in 22% of the young-onset cases. Assessment of germline risk is critical for personalized cancer care.

OBJECTIVE

The study aimed to implement universal germline cancer risk assessment and testing and to define the germline cancer risk profiles of patients presenting with young-onset disease.

DESIGN

This is a prospective cohort study.

SETTINGS

This study was conducted at a tertiary-referral academic medical center.

PATIENTS

This study included newly diagnosed patients presenting to surgical clinics between September 2019 and February 2021 who were treated on a standardized care pathway including the universal germline risk assessment.

INTERVENTIONS

Patients received educational material on young-onset disease, genetic testing, and insurance coverage followed by genetic counseling (either remotely by telegenetics or in person). Consenting patients were assessed on a 47-gene common hereditary cancer panel.

MAIN OUTCOME MEASURES

The primary outcome was a proportion of patients with identifiable germline cancer predisposition.

RESULTS

Among 500 patients with colorectal cancer, 185 (37%) were 50 years of age or younger (median: 44). A family history was absent for the majority of patients (123; 67%), and in 15 patients, tumors (8.1%) were deficient in DNA mismatch repair. Germline testing was completed in 130 patients (70%); the remainder were pending (7%), deceased (1%), or declined (22%). Pathogenic germline mutations were identified in 25 of 130 (19%) patients: 12 in mismatch repair genes and 13 in other genes. A variant of uncertain significance was found in 23 (18%) patients. Importantly, a pathogenic germline mutation was identified in 12% of the patients without a family history (versus 32% with; p = 0.015) and in 13% of those with proficient mismatch repair colorectal cancers (versus 71% if deficient; p < 0.001).

LIMITATIONS

The study is limited by its implementation at a single tertiary academic institution.

CONCLUSIONS

One in 5 patients with young-onset disease harbored germline cancer predisposition. This detection rate, coupled with a high level of interest and acceptance from patients and feasibility of implementation, supports universal germline cancer risk assessment in this patient population. See Video Abstract at http://links.lww.com/DCR/B925 .

PERFILES DE RIESGO DE CNCER DE LNEA GERMINAL DE PACIENTES CON CNCER COLORRECTAL DE INICIO JOVEN HALLAZGOS DE UN PROGRAMA UNIVERSAL PROSPECTIVO DE PRUEBAS DE LNEA GERMINAL Y TELEGENTICA

ANTECEDENTES:El cáncer colorrectal se diagnostica cada vez más en personas menores de 50 años. Se ha informado una predisposición hereditaria al cáncer en el 22 % de los casos de aparición temprana. La evaluación del riesgo de la línea germinal es fundamental para la atención personalizada del cáncer.OBJETIVO:Implementar la evaluación y las pruebas universales de riesgo de cáncer de línea germinal, y definir los perfiles de riesgo de cáncer de línea germinal de los pacientes que presentan una enfermedad de aparición temprana.DISEÑO:Un estudio de cohorte prospectivo.AJUSTE:Un centro médico académico de referencia terciaria.PACIENTES:Los pacientes recién diagnosticados que se presentaron en clínicas quirúrgicas entre Septiembre de 2019 y Febrero de 2021 fueron tratados en una vía de atención estandarizada que incluye una evaluación de riesgo de línea germinal universal.INTERVENCIÓN:Los pacientes recibieron material educativo sobre enfermedades de aparición temprana, pruebas genéticas y cobertura de seguro, seguido de asesoramiento genético (ya sea a distancia por telegenética o en persona). Los pacientes que dieron su consentimiento fueron evaluados en un panel de cánceres hereditarios comunes de 47 genes.MEDIDA DE RESULTADO PRINCIPAL:Proporción de pacientes con predisposición identificable al cáncer de línea germinal.RESULTADOS:Entre 500 pacientes con cáncer colorrectal, 185 (37%) tenían 50 años o menos (mediana: 44). No había antecedentes familiares en la mayoría (123, 67%) y 15 tumores (8,1%) eran deficientes en la reparación del desajuste de ácido desoxirribonucleico. La prueba de línea germinal se completó en 130 pacientes (70%); el resto estaban pendientes (7%), fallecidos (1%) o declinados (22%). Se identificaron mutaciones patogénicas de la línea germinal en 25 (de 130, 19%) pacientes: 12 en genes de reparación de errores de emparejamiento y 13 en otros genes. Se encontró una variante de significado incierto en 23 (18%) pacientes. Es importante señalar que se identificó una mutación germinal patogénica en el 12% de los pacientes sin antecedentes familiares (frente al 32% con; p = 0,015) y en el 13% de aquellos con cánceres colorrectales competentes en la reparación de errores de emparejamiento (frente al 71% si eran deficientes; p < 0,001).LIMITACIÓN:Implementado en una sola institución académica terciaria.CONCLUSIÓN:Uno de cada cinco pacientes con enfermedad de inicio joven albergaba predisposición al cáncer de línea germinal. Esta tasa de detección, junto con un alto nivel de interés y aceptación por parte de los pacientes y la viabilidad de la implementación, respaldan la evaluación universal del riesgo de cáncer de línea germinal en esta población de pacientes. Consulte el Video Resumen en http://links.lww.com/DCR/B925 . (Traducción-Dr. Yesenia Rojas-Khalil ).

Interventions to improve delivery of cancer genetics services in the United States: A scoping review

PURPOSE

Interventions that decrease barriers and improve clinical processes can increase patient access to guideline-recommended cancer genetics services. We sought to identify and describe interventions to improve patient receipt of guideline-recommended cancer genetics services in the United States.

METHODS

We performed a comprehensive search in Ovid MEDLINE and Embase, Scopus, and Web of Science from January 1, 2000 to February 12, 2020. Eligible articles reported interventions to improve the identification, referral, genetic counseling (GC), and genetic testing (GT) of patients in the United States. We independently screened titles and abstracts and reviewed full-text articles. Data were synthesized by grouping articles by clinical process.

RESULTS

Of 44 included articles, 17 targeted identification of eligible patients, 14 targeted referral, 15 targeted GC, and 16 targeted GT. Patient identification interventions included universal tumor testing and screening of medical/family history. Referral interventions included medical record system adaptations, standardizing processes, and provider notifications. GC interventions included supplemental patient education, integrated GC within oncology clinics, appointment coordination, and alternative service delivery models. One article directly targeted the GT process by implementing provider-coordinated testing.

CONCLUSION

This scoping review identified and described interventions to improve US patients' access to and receipt of guideline-recommended cancer genetics services.

Patient navigation for hereditary colorectal cancer: Design of a randomized controlled trial to determine the effectiveness of pathways to genetic counseling

BACKGROUND

Diagnosis of Lynch and other hereditary colorectal cancer (CRC) syndromes through germline genetic testing has important implications for treatment and risk-management, yet guideline-recommended genetic counseling referral and attendance is suboptimal.

METHODS

Our team developed an adapted patient navigation program-Pathways to Genetic Counseling-to address multilevel barriers to genetic counseling referral and receipt. This paper describes the methods of a randomized controlled trial (RCT) testing Pathways to Genetic Counseling's effectiveness at increasing genetic counseling attendance in the University of Washington Medicine health system. We will identify CRC patients eligible for genetic counseling (diagnosed before age 50 or at any age with evidence of inherited mismatch repair deficiency) through a combination of structured electronic health record queries and manual chart review. Patients will be randomized 1:1 prior to consent and receive either care as usual (no contact) or be invited to participate in patient navigation. We will use chart review to compare rates of genetic counseling referral and attendance within six months of randomization, regardless of patients' engagement with navigation. We plan to identify and randomize 161 eligible CRC patients over a nine-month period beginning in late 2021.

DISCUSSION

Our pragmatic RCT design will provide real-world data on the potential for patient navigation to address longstanding care gaps in preventive genomic medicine. If effective, we hope to pilot Pathways to Genetic Counseling in additional settings with a long-term goal of improving appropriate diagnosis of hereditary CRC syndromes and subsequent cascade screening of eligible family members.

Worldwide variation in lynch syndrome screening: case for universal screening in low colorectal cancer prevalence areas

To perform a systematic assessment of universal Lynch syndrome (LS) screening yield in colorectal cancer (CRC) patients around the world. Universal screening for LS is recommended in all CRC patients. However, the variation in yield of LS screening in the setting of significant global variation in CRC prevalence is unknown. A systematic review of articles in the MEDLINE database was performed to identify studies performing universal screening for LS. All cases with microsatellite instability (MSI-H) or missing one or more proteins on immunohistochemistry (IHC) were considered screening positive. The overall pooled yield of universal LS screening in 97 study arms from 89 identified studies was 11.9% (5649/47545) and the overall pooled percentage of confirmed LS patients was 1.8% (682/37220). LS screening positivity varied significantly based on geographic region (Kruskal Wallis test, p < 0.001) and reported 5-year CRC prevalence in the country (Fisher's exact, p < 0.001). Significant inverse correlation was found between LS screening positivity and 5-year CRC prevalence (Pearson correlation, r =  - 0.56, p < 0.001). The overall yield of LS screening was 15.00% (382/2553) and rate of confirmed LS was 7.7% (113/1475) in LS screening done in patients ≤ 50 years (16 studies). There is significant geographic variation in LS screening positivity with higher yield in countries with lower prevalence of CRC. Our results highlight the importance of universal LS screening in younger patients and low CRC prevalence countries.

Colorectal Cancer in the Adolescent and Young Adult Population

Colorectal cancer in the young adult population is of increasing incidence and concern. Genetic predisposition and heritable syndromes contribute to this trend, but perhaps more concerning is the majority of new diagnoses that involve no traceable genetic risk factors. Prevention and early recognition, with a high suspicion in the symptomatic young adult, are critical in attenuating recent trends. Clinical management requires coordinated multidisciplinary care from diagnosis to surveillance in order to ensure appropriate management. This review provides a summary of key aspects related to colorectal cancer in adolescents and young adults, including epidemiology, biology, genetics, clinical management, and prevention.

Molecular testing for Lynch syndrome in people with colorectal cancer: systematic reviews and economic evaluation

BACKGROUND

Inherited mutations in deoxyribonucleic acid (DNA) mismatch repair (MMR) genes lead to an increased risk of colorectal cancer (CRC), gynaecological cancers and other cancers, known as Lynch syndrome (LS). Risk-reducing interventions can be offered to individuals with known LS-causing mutations. The mutations can be identified by comprehensive testing of the MMR genes, but this would be prohibitively expensive in the general population. Tumour-based tests - microsatellite instability (MSI) and MMR immunohistochemistry (IHC) - are used in CRC patients to identify individuals at high risk of LS for genetic testing. MLH1 (MutL homologue 1) promoter methylation and BRAF V600E testing can be conducted on tumour material to rule out certain sporadic cancers.

OBJECTIVES

To investigate whether testing for LS in CRC patients using MSI or IHC (with or without MLH1 promoter methylation testing and BRAF V600E testing) is clinically effective (in terms of identifying Lynch syndrome and improving outcomes for patients) and represents a cost-effective use of NHS resources.

REVIEW METHODS

Systematic reviews were conducted of the published literature on diagnostic test accuracy studies of MSI and/or IHC testing for LS, end-to-end studies of screening for LS in CRC patients and economic evaluations of screening for LS in CRC patients. A model-based economic evaluation was conducted to extrapolate long-term outcomes from the results of the diagnostic test accuracy review. The model was extended from a model previously developed by the authors.

RESULTS

Ten studies were identified that evaluated the diagnostic test accuracy of MSI and/or IHC testing for identifying LS in CRC patients. For MSI testing, sensitivity ranged from 66.7% to 100.0% and specificity ranged from 61.1% to 92.5%. For IHC, sensitivity ranged from 80.8% to 100.0% and specificity ranged from 80.5% to 91.9%. When tumours showing low levels of MSI were treated as a positive result, the sensitivity of MSI testing increased but specificity fell. No end-to-end studies of screening for LS in CRC patients were identified. Nine economic evaluations of screening for LS in CRC were identified. None of the included studies fully matched the decision problem and hence a new economic evaluation was required. The base-case results in the economic evaluation suggest that screening for LS in CRC patients using IHC, BRAF V600E and MLH1 promoter methylation testing would be cost-effective at a threshold of £20,000 per quality-adjusted life-year (QALY). The incremental cost-effectiveness ratio for this strategy was £11,008 per QALY compared with no screening. Screening without tumour tests is not predicted to be cost-effective.

LIMITATIONS

Most of the diagnostic test accuracy studies identified were rated as having a risk of bias or were conducted in unrepresentative samples. There was no direct evidence that screening improves long-term outcomes. No probabilistic sensitivity analysis was conducted.

CONCLUSIONS

Systematic review evidence suggests that MSI- and IHC-based testing can be used to identify LS in CRC patients, although there was heterogeneity in the methods used in the studies identified and the results of the studies. There was no high-quality empirical evidence that screening improves long-term outcomes and so an evidence linkage approach using modelling was necessary. Key determinants of whether or not screening is cost-effective are the accuracy of tumour-based tests, CRC risk without surveillance, the number of relatives identified for cascade testing, colonoscopic surveillance effectiveness and the acceptance of genetic testing. Future work should investigate screening for more causes of hereditary CRC and screening for LS in endometrial cancer patients.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016033879.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

The current value of determining the mismatch repair status of colorectal cancer: A rationale for routine testing. Crit Rev Oncol Hematol. 2017;116:38-57. [PMID: 28693799 DOI: 10.1016/j.critrevonc.2017.05.006]

Colorectal Cancer (CRC) is the third most prevalent cancer in men and women. Up to 15% of CRCs display microsatellite instability (MSI). MSI is reflective of a deficient mismatch repair (MMR) system and is most commonly caused by hypermethylation of the MLH1 promoter. However, it may also be due to autosomal dominant constitutional mutations in DNA MMR, termed Lynch Syndrome. MSI may be diagnosed via polymerase chain reaction (PCR) or alternatively, immunohistochemistry (IHC) can identify MMR deficiency (dMMR). Many institutions now advocate universal tumor screening of CRC via either PCR for MSI or IHC for dMMR to guide Lynch Syndrome testing. The association of sporadic MSI with methylation of the MLH1 promoter and an activating BRAF mutation may offer further exclusion criteria for genetic testing. Aside from screening for Lynch syndrome, MMR testing is important because of its prognostic and therapeutic implications. Several studies have shown MSI CRCs exhibit different clinicopathological features and prognosis compared to microsatellite-stable (MSS) CRCs. For example, response to conventional chemotherapy has been reported to be less in MSI tumours. More recently, MSI tumours have been shown to be responsive to immune-checkpoint inhibition providing a novel therapeutic strategy. This provides a rationale for routine testing for MSI or dMMR in CRC.

DNA Mismatch Repair Deficiency in Rectal Cancer: Benchmarking Its Impact on Prognosis, Neoadjuvant Response Prediction, and Clinical Cancer Genetics

PURPOSE

DNA mismatch repair deficiency (dMMR) hallmarks consensus molecular subtype 1 of colorectal cancer. It is being routinely tested, but little is known about dMMR rectal cancers. The efficacy of novel treatment strategies cannot be established without benchmarking the outcomes of dMMR rectal cancer with current therapy. We aimed to delineate the impact of dMMR on prognosis, the predicted response to fluoropyrimidine-based neoadjuvant therapy, and implications of germline alterations in the MMR genes in rectal cancer.

METHODS

Between 1992 and 2012, 62 patients with dMMR rectal cancers underwent multimodality therapy. Oncologic treatment and outcomes as well as clinical genetics work-up were examined. Overall and rectal cancer-specific survival were calculated by the Kaplan-Meier method.

RESULTS

The median age at diagnosis was 41 years. MMR deficiency was most commonly due to alterations in MSH2 (53%) or MSH6 (23%). After a median follow-up of 6.8 years, the 5-year rectal cancer-specific survival was 100% for stage I and II, 85.1% for stage III, and 60.0% for stage IV disease. Fluoropyrimidine-based neoadjuvant chemoradiation was associated with a complete pathologic response rate of 27.6%. The extent of surgical resection was influenced by synchronous colonic disease at presentation, tumor height, clinical stage, and pelvic radiation. An informed decision for a limited resection focusing on proctectomy did not compromise overall survival. Five of the 11 (45.5%) deaths during follow-up were due to extracolorectal malignancies.

CONCLUSION

dMMR rectal cancer had excellent prognosis and pathologic response with current multimodality therapy including an individualized surgical treatment plan. Identification of a dMMR rectal cancer should trigger germline testing, followed by lifelong surveillance for both colorectal and extracolorectal malignancies. We herein provide genotype-specific outcome benchmarks for comparison with novel interventions.