Keywords:
Breast, MR, Screening, Neoplasia, Genetic defects
Authors:
A. Pecchi, V. Marchesi, R. Battista, B. Canossi, L. Cortesi, P. Torricelli; Modena/IT
DOI:
10.1594/ecr2013/C-2466
Purpose
Women with a strong family history of breast cancer (BC) or a predisposing gene mutation such as BRCA1 or BRCA2 have a cumulative lifetime risk of developing BC of 21-65% [1] with a substantial proportion of these cancer diagnosed before the age of 50 years.
Prophylactic mastectomy,
oophorectomy and chemoprevention with a selective oestrogen receptor modulator such as tamoxifen can reduce this risk but are associated with adverse events,
are ethically questionable,
and may be unacceptable options for some women.
Surveillance of high risk women with breast imaging is recommended as a secondary preventive measure on the assumption that early diagnosis and treatment will confer similar benefits of reduced BC mortality in this population as reported from randomised controlled trials of population screening programs using mammography (MX) in average risk women.
Although MX is a reasonably sensitive test for screening postmenopausal women,
it is less sensitive in younger women and those with a genetic predisposition to BC.
This has been attributed to increased mammographic density in premenopausal women which can obscure the radiological features of early BC and the faster growth of BC in these populations.
Further,
it has been suggested that cancer associated with BRCA mutations,
in particular BRCA1,
are more likely to have a benign appearance on MX [2].
The use of breast ultrasound (US) as a supplemental modality for BC screening has been studied in women with dense breast tissue and in those with an elevated risk for BC.
The benefits of US as a screening modality are that it does not use ionizing radiation,
is well-tolerated and is optimally amenable for percutaneous biopsy guidance.
US is able to identify small non-palpable masses while undeterred by presence of dense breast tissue,
which is an inherent limitation of MX; but the vast majorities of cancer that are seen on US are invasive cancers,
DCIS is not usually identified by sonography.
Furthermore,
US is an operator-dependent examination; standardization of the examination and having a skilled,
adequately trained sinologist are critical for performance of a whole breastUS.
Emerging evidence that MRI is more sensitive than MX and US for the detection of BC,
in particular for DCIS; and recent studies have validated the role of MRI screening in high risk populations.
Previous reports in high risk populations have shown overall sensitivity of MRI approximately double that of routine MX [5,6,7].
Unlike MX,
MRI is unaffected by breast density and does not use ionizing radiation.
The use of breast MRI for screening the general population is not practical because of its high cost,
limited availability,
and relatively low specificity and the difficulty of sampling lesions visible only on MRI; limiting its use to a very high-risk population is more appropriate.
Several single-center and multicenter studies have evaluated MRI screening in women with hereditary risk for BC.
The study aim is to evaluate pros and cons of breast magnetic resonance imaging (MRI) in a population with high risk of developing breast cancer at “Modena Cancer Centre for Hereditary Breast and Ovarium Cancer”.