ABSTRACT
Women who carry the BRCA mutation are at high lifetime risk of breast cancer, but there is no consensus regarding an effective and safe chemoprevention strategy. A large body of evidence suggests that 3,3-diindolylmethane (DIM), a dimer of indole-3-carbinol found in cruciferous vegetables, can potentially prevent carcinogenesis and tumor development. The primary aim of this prospective single-arm study was to investigate the effect of DIM supplementation on breast density, a recognized predictive factor of breast cancer risk. Participants were 23 healthy female BRCA carriers (median age 47 years; 78% postmenopausal) who were treated with oral DIM 100 mg × 1/day for 1 year. The amount of fibroglandular tissue (FGT) and background parenchymal enhancement (BPE) on magnetic resonance imaging (MRI) performed before and after the intervention was scored by two independent expert radiologists using the Breast Imaging and Reporting Data System. The results showed a decrease in the average score for FGT amount from 2.8 ± 0.8 at the onset to 2.65 ± 0.84 after 1 year (P = 0.031), with no significant change in BPE (P = 0.429). A group of DIM-untreated age- and menopausal-status-matched women from the BRCA clinic did not show a significant change in FGT amount (P = 0.33) or BPE (P = 0.814) in a parallel year. Mean estradiol level decreased from 159 to 102 pmol/l (P = 0.01), and mean testosterone level decreased from 0.42 to 0.31 pmol/l (P = 0.007). Side effects were grade 1. In conclusion, 1 year's supplementation with DIM 100 mg × 1/day in BRCA carriers was associated with a significant decline in FGT amount on MRI. Larger randomized studies are warranted to corroborate these findings.
Subject(s)
Anticarcinogenic Agents/administration & dosage , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Breast Density/drug effects , Breast Neoplasms/genetics , Breast Neoplasms/prevention & control , Carcinogenesis/drug effects , Indoles/administration & dosage , Adult , Aged , Anticarcinogenic Agents/pharmacology , Female , Heterozygote , Humans , Indoles/pharmacology , Middle AgedABSTRACT
BACKGROUND: Women who carry the BRCA gene mutation have an up to 80% chance of developing cancer, primarily of breast and ovarian origin. Confirmation of carrier status is described by many women as an overwhelming, life-changing event. Healthy individuals harboring a BRCA mutation constitute a high risk population with unique needs, often overlooked by health authorities. As such, we felt the need to create a specialized service dedicated specifically to this high risk population. The clinic staff comprises an experienced multidisciplinary team of health professionals who can support the medical and emotional needs of this population. Since its inception in 2001 the clinic has served 318 women. The mean age of patients is 46 years. With a median follow-up of 46 months, 21 women have developed malignancies, including 17 breast cancers, 1 ovarian cancer and 3 additional cancers. All but one of the patients above the age of 40 underwent bilateral salpingo-oophorectomy (BSO). The median and mean ages at BSO were 46.5 and 48 years, respectively (range 33-68). However, only 28.3% underwent bilateral preventive mastectomy. A multidisciplinary clinic for BRCA mutation carriers provides a "home" for this unique population with unmet needs. The high rate of BSO in women before natural menopause indicates that both the medical community and this population are aware of international guidelines supporting this procedure. We believe that a dedicated clinic, with a multidisciplinary team, is likely to contribute to the health, quality of life and survival of BRCA carriers.
