Obdeijn, I.M.

Assessment of false-negative cases of breast MR imaging in women with a familial or genetic predisposition (Article)

2010-01-01T00:00:00Z

In order to assess the characteristics of malignant breast lesions those were not detected during screening by MR imaging. In the Dutch MRI screening study (MRISC), a non-randomized prospective multicenter study, women with high familial risk or a genetic predisposition for breast cancer were screened once a year by mammography and MRI and every 6 months with a clinical breast examination (CBE). The false-negative MR examinations were subject of this study and were retrospectively reviewed by two experienced radiologists. From November 1999 until March 2006, 2,157 women were eligible for study analyses. Ninety-seven malignant breast tumors were detected, including 19 DCIS (20%). In 22 patients with a malignant lesion, the MRI was assessed as BI-RADS 1 or 2. One patient was excluded because the examinations were not available for review. Forty-three percent (9/21) of the false-negative MR cases concerned pure ductal carcinoma in situ (DCIS) or DCIS with invasive foci, in eight of them no enhancement was seen at the review. In six patients the features of malignancy were missed or misinterpreted. Small lesion size (n = 3), extensive diffuse contrast enhancement of the breast parenchyma (n = 2), and a technically inadequate examination (n = 1) were other causes of the missed diagnosis. A major part of the false-negative MR diagnoses concerned non-enhancing DCIS, underlining the necessity of screening not only with MRI but also with mammography. Improvement of MRI scanning protocols may increase the detection rate of DCIS. The missed and misinterpreted cases are reflecting the learning curve of a multicenter study.

Breast tumor characteristics of BRCA1 and BRCA2 gene mutation carriers on MRI (Article)

2008-05-01T00:00:00Z

The appearance of malignant lesions in BRCA1 and BRCA2 mutation carriers (BRCA-MCs) on mammography and magnetic resonance imaging (MRI) was evaluated. Thus, 29 BRCA-MCs with breast cancer were retrospectively evaluated and the results compared with an age, tumor size and tumor type matched control group of 29 sporadic breast cancer cases. Detection rates on both modalities were evaluated. Tumors were analyzed on morphology, density (mammography), enhancement pattern and kinetics (MRI). Overall detection was significantly better with MRI than with mammography (55/58 vs 44/57, P = 0.021). On mammography, lesions in the BRCA-MC group were significantly more described as rounded (12//19 vs 3/13, P = 0.036) and with sharp margins (9/19 vs 1/13, P = 0.024). On MRI lesions in the BRCA-MC group were significantly more described as rounded (16/27 vs 7/28, P = 0.010), with sharp margins (20/27 vs 7/28, P < 0.001) and with rim enhancement (7/27 vs 1/28, P = 0.025). No significant difference was found for enhancement kinetics (P = 0.667). Malignant lesions in BRCA-MC frequently have morphological characteristics commonly seen in benign lesions, like a rounded shape or sharp margins. This applies for both mammography and MRI. However the possibility of MRI to evaluate the enhancement pattern and kinetics enables the detection of characteristics suggestive for a malignancy.

BRCA1 mutation and young age predict fast breast cancer growth in the Dutch, United Kingdom, and Canadian magnetic resonance imaging screening trials (Article)

2007-12-15T00:00:00Z

Purpose: Magnetic resonance imaging (MRI) screening enables early detection of breast cancers in women with an inherited predisposition. Interval cancers occurred in women with a BRCA1 mutation, possibly due to fast tumor growth. We investigated the effect of a BRCA1 or BRCA2 mutation and age on the growth rate of breast cancers, as this may influence the optimal screening frequency. Experimental Design: We reviewed the invasive cancers from the United Kingdom, Dutch, and Canadian MRI screening trials for women at hereditary risk, measuring tumor size at diagnosis and on preceding MRI and/or mammography. We could assess tumor volume doubling time (DT) in 100 cancers. Results: Tumor DT was estimated for 43 women with a BRCA1 mutation, 16 women with a BRCA2 mutation, and 41 women at high risk without an identified mutation. Growth rate slowed continuously with increasing age (P = 0.004). Growth was twice as fast in BRCA1 (P = 0.003) or BRCA2 (P = 0.03) patients as in high-risk patients of the same age. The mean DT for women with BRCA1/2 mutations diagnosed at ages ≤40, 41 to 50, and >50 years was 28, 68, and 81 days, respectively, and 83, 121, and 173 days, respectively, in the high-risk group. Pathologic tumor size decreased with increasing age (P = 0.001). Median size was 15 mm for patients ages ≤40 years compared with 9 mm in older patients (P = 0.003); tumors were largest in young women with BRCA1 mutations. Conclusion: Tumors grow quickly in women with BRCA1 mutations and in young women. Age and risk group should be taken into account in screening protocols.

Tumor characteristics and detection method in the MRISC screening program for the early detection of hereditary breast cancer (Article)

2007-05-01T00:00:00Z

In the MRISC study, women with an inherited risk for breast cancer were screened by a 6-month clinical breast examination (CBE) and yearly MRI and mammography. We found that the MRISC screening scheme could facilitate early breast cancer diagnosis and that MRI was a more sensitive screening method than mammography, but less specific. In the current study we investigated the contribution of MRI in the early detection of breast cancer in relation to tumor characteristics. From November 1999 to October 2003, 1909 women were included and 50 breast cancers were detected, of which 45 were evaluable and included in the current study. We compared the characteristics of tumors detected by MRI-only with those of all other (non-palpable) screen-detected tumors. Further, we compared the sensitivity of mammography and MRI within subgroups according to different tumor characteristics. Twenty-two (49%) of the 45 breast cancers were detected by MRI and not visible at mammography, of which 20 (44%) were also not palpable (MRI-only detected tumors). MRI-only detected tumors were more often node-negative than other screen-detected cancers (94 vs. 59%; P = 0.02) and tended to be more often ≤1 cm (58 vs. 31%; P = 0.11). MRI was more sensitive than mammography for a wide spectrum of invasive tumor characteristics i.e., size, nodal status, histology, grade and ER status. Half of the breast cancers detected in this study were visible by MRI only and these tumors were smaller and significantly more often node-negative than other screen-detected tumors, suggesting that MRI makes an important contribution to the early detection of hereditary breast cancer.

Efficacy of MRI and mammography for breast-cancer screening in women with a familial or genetic predisposition (Article)

2004-01-01T00:00:00Z

BACKGROUND: The value of regular surveillance for breast cancer in women with a genetic or familial predisposition to breast cancer is currently unproven. We compared the efficacy of magnetic resonance imaging (MRI) with that of mammography for screening in this group of high-risk women. METHODS: Women who had a cumulative lifetime risk of breast cancer of 15 percent or more were screened every six months with a clinical breast examination and once a year by mammography and MRI, with independent readings. The characteristics of the cancers that were detected were compared with the characteristics of those in two different age-matched control groups. RESULTS: We screened 1909 eligible women, including 358 carriers of germ-line mutations. Within a median follow-up period of 2.9 years, 51 tumors (44 invasive cancers, 6 ductal carcinomas in situ, and 1 lymphoma) and 1 lobular carcinoma in situ were detected. The sensitivity of clinical breast examination, mammography, and MRI for detecting invasive breast cancer was 17.9 percent, 33.3 percent, and 79.5 percent, respectively, and the specificity was 98.1 percent, 95.0 percent, and 89.8 percent, respectively. The overall discriminating capacity of MRI was significantly better than that of mammography (P<0.05). The proportion of invasive tumors that were 10 mm or less in diameter was significantly greater in our surveillance group (43.2 percent) than in either control group (14.0 percent [P<0.001] and 12.5 percent [P=0.04], respectively). The combined incidence of positive axillary nodes and micrometastases in invasive cancers in our study was 21.4 percent, as compared with 52.4 percent (P<0.001) and 56.4 percent (P=0.001) in the two control groups. CONCLUSIONS: MRI appears to be more sensitive than mammography in detecting tumors in women with an inherited susceptibility to breast cancer.