Breast MRI of pure ductal carcinoma in situ: sensitivity of diagnosis and influence of lesion characteristics.

OBJECTIVES: The purpose of the study was to evaluate the sensitivity of breast MRI in the detection of pure DCIS and to analyze the influence of lesion type and nuclear grade. METHODS: 58 consecutive patients with pathologically proven pure DCIS and preoperatively performed breast MRI were retrospectively reviewed and analyzed. Sensitivities in the detection of DCIS were calculated for MRI and mammography (Mx). Influence of MRI lesion type and nuclear grading on DCIS diagnosis was evaluated. RESULTS: MRI detected pure DCIS with a sensitivity of 79.3%. The sensitivity of Mx was lower (69%), but the difference was not statistically significant (p=0.345). 46.2% of the DCIS presented as enhancing mass and 53.8% as non-mass-like enhancement (NMLE). None of the masses but 21.4% (n=6) of the NMLE were underestimated as probably benign (BI-RADS 3). MRI measured lesion sizes showed a moderate correlation (r=0.74) with histopathologically measured lesion sizes. MRI detection rate of DCIS decreased significantly (p=0.0458) with increasing nuclear grade. Calculated sensitivities were 100% for low-grade DCIS, 84.6% for intermediate-grade DCIS, and 66.7% for high-grade DCIS. CONCLUSIONS: In this study MRI could detect pure DCIS more sensitively than Mx. Despite of missing statistically significance preoperative MRI seems to be helpful in patients with DCIS who are eligible for breast conservation. This applies in particular to patients with non-high-grade DCIS because those were significantly more often positive on MRI and significantly more often negative on Mx. Misinterpretation occurs especially in cases of NMLE and high-grade DCIS and therefore a correlation with Mx is also recommended.

Dynamic magnetic resonance imaging for assessment of minimally invasive pelvic floor reconstruction with polypropylene implant.

INTRODUCTION: The purpose of the study was to assess the usefulness of dynamic MRI in patients with pelvic organ prolapse after pelvic floor repair with polypropylene mesh. MATERIALS AND METHODS: Fifteen consecutive patients (mean age 66.5 years) who were scheduled for either anterior (n=9) or posterior (n=6) pelvic floor repair were prospectively evaluated by clinical assessment and dynamic MRI 1 day before and 3 months after surgery. MRI diagnoses and MRI measurements of relevant anatomical points at rest and on straining were analysed before and after surgery. RESULTS: At follow-up assessment 93.3% of all patients were clinically cured. Dynamic MRI showed newly developed (n=6) or increased (n=6) pelvic organ prolapse in 80% (n=12) of all patients 3 months after pelvic floor repair. Most of them (n=11; 91.7%) affected the untreated pelvic floor compartment. On straining anatomical points of reference in the anterior pelvic floor compartment were significantly (p<0.05) elevated after anterior repair and rectal bulging was significantly (p=0.036) reduced after posterior pelvic floor repair. CONCLUSIONS: In this study dynamic MRI could verify the effective support of anterior and posterior pelvic floor structures by anterior and posterior polypropylene implant respectively. But dynamic MRI demonstrates if one compartment of the pelvic floor is repaired another compartment frequently (73.3%) develops dysfunction. These results did not correspond to clinical symptoms on short-term follow-up (3 months). Studies with long-term follow-up are necessary to prove if dynamic MRI can reliably identify clinically significant pelvic organ prolapse after pelvic floor repair before the onset of symptoms.