Abstract P6-12-09: Uptake of genetic testing for BRCA mutations in a medically underserved population
Authors: Gaber RS , Thekkekara RJ , Gil DN , Holden CM , Aluen Metzner I , Marcus E , Ganschow PS 
Published: May 2016

Introduction:

Genetic testing for hereditary cancer syndromes is recommended in specific populations to identify individuals at increased risk for developing malignancies. The uptake of genetic testing for BRCA mutations in studies has ranged from 44%-81% but has not been well studied in medically underserved populations. In this study we identified factors that predicted uptake of genetic testing among a medically underserved population undergoing genetic counseling in the Cancer Risk Program at a safety net hospital in Chicago.

Methods:

A retrospective cohort design was used. Data were abstracted from the medical records of 150 consecutive individuals who underwent genetic counseling for BRCA mutation testing in the Cancer Risk clinic at John H Stroger Jr., Hospital of Cook County between October 2013 and July 2014. The primary outcome measure was the uptake of genetic testing among individuals in whom the test was recommended after genetic counseling. Final testing status was assessed as of April 30, 2015. Individuals referred for testing of genetic syndromes other than hereditary breast and ovarian cancers were excluded from this analysis. Data regarding personal and family history of cancer and socio-demographic determinants- age, sex, ethnicity and insurance status were collected.

Results:

Among the 150 individuals who underwent genetic counseling, the mean age was 49 years (range 19-74 years) and only 5 were men. Forty-three percent were African American, 34% were Hispanic and 11% were Caucasian. Sixty seven percent were uninsured and 30% had public insurance. Forty-one percent had a personal history of cancer (36% with breast cancer, 3% with pelvic cancer). Eighty five percent of the individuals had 2 or more relatives with cancer in the family. Genetic testing was recommended in 112 individuals (75%) after assessment and counseling by the genetic counselor. Of those recommended, 89 individuals (80%) underwent genetic testing. Among the men, 4 (80%) were recommended for testing and 3 (75%) underwent testing. Genetic testing was not recommended for 20 individuals (13%) and of the remaining 18 individuals (12%), testing of a living affected relative was recommended first. Only one of the 18 individuals returned with genetic test results from an affected family member during the study period. The only positive predictor of testing was age less than 50 years (OR 3.63; 95% CI 1.31-10.08). Having one or more siblings with cancer was a negative predictor of uptake of testing (OR 0.35; 95% CI 0.13-0.90).

Conclusions:

Uptake of genetic testing was high among our cohort of medically underserved individuals. While prior studies have shown a variable association between age and uptake of testing, younger individuals in our cohort were more likely to undergo testing. Interestingly, while most studies have shown an increased uptake of testing among individuals who have a family history of cancer, having cancer in a sibling was a barrier to testing in our cohort and warrants further study. The very low number of men counseled and tested during the study period also suggests that strategies are needed to extend genetic counseling and testing to at-risk men in medically underserved communities.

Citation Format: Gaber RS, Thekkekara RJ, Gil DN, Holden CM, Aluen Metzner I, Marcus E, Ganschow PS. Uptake of genetic testing for BRCA mutations in a medically underserved population. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-12-09.