The contribution of dynamic contrast enhanced mri in the diagnosis of breast cancer

Background: Breast MRI has evolved as a promising complimentary sensitive tool for detection and local staging of breast cancer. In this study our goal was to determine the role of MRI in the preoperative assessment of breast cancer in conjunct with the traditional imaging modalities. Patients and methods: This prospective study was performed during the period from November 2012 to December 2013 at the Medical City Teaching Center. A selected sample of 50 female patients aged from 30-74years with a mean age of 51 year having clinical suspicion of breast cancers; were subjected to mammographic and ultrasonic classification in the breast clinic of the Oncology Hospital, confirmed by FNAC and referred to the MRI unit of Baghdad Teaching Hospital where DCE-MRI were done, utilizing a special breast coil and bilateral axial high resolution 3D scan. Histopathological confirmation was obtained from 32 patients of the study sample. Results: MRI interpretations in our study depend upon the enhancement pattern but basically on the temporal resolution and kinetic analysis, and patients were classified according to the Breast Imaging Reporting and Data System (BIRADS classification) as BIRADS IV and V with one patient that had a BIRADS VI. Breast MRI provides a more precise evaluation of the size of breast lesions than that obtained by US. It also determines the extent of primary cancer and chest wall invasion as well as local recurrence of a previous lesion more precisely than other imaging modalities. It has the ability to detect multifocal and bilateral lesions that did not be picked up by mammography and ultrasound. Five histopathological types were found in our study. Invasive ductal carcinoma found to be the most common accounting about 65 % of cases. MRI diagnostic yield in correlation with histopathological detection of breast cancer had a sensitivity of 93.75%. It has shown to increase the sensitivity of traditional modalities up to 100 % instead of combined sensitivity by mammography and ultrasound that did not exceed 84%. The sensitivity, specificity, accuracy and positive predictive value of breast MRI based on cytological diagnosis proved to be: 95%, 66% and 86% and 97% respectively. MRI assessment of axillary lymphadenopathy wasn’t specific in our study with 61 % false positive cases regarding the kinetic analysis curves. However; morphology, signal intensity and pattern of enhancement may be suggestive about the nature of LAP. Hormonal effect on temporal resolution and the pattern of enhancement of normal breast tissue was found to display false positive type 3 malignant curves in two of our patients whom scan were performed during or shortly after their menstrual cycle. Conclusion: This study has revealed that DCE-MRI is the most sensitive modality in detecting breast cancer and has an important role in the preoperative assessment and work - up that can lead to better outcome as it enables the detection of cancers that are occult in other conventional imaging modalities. Most importantly; it's more sensitive in detecting multifocal and bilateral breast cancer and more accurate than US for assessing the size and extent of primary breast cancer presenting as a mass. It has a useful role in detecting local recurrence in addition. Recommendations: Because of the world wide promising role of breast MRI; we recommend an establishment of a specialized unit with a well-qualified and expect staff as this will allow proper selection of high risk group population that improves early detection of breast cancer and hence better prognosis Further studies with larger samples are recommended with more detailed evaluation of each of MRI indication to determine the effect of its utilization in planning management and improving the outcome. To increase specificity; proper selection of high risk patients and proper timing for premenopausal patients to perform their breast MRI between day 7and 14 of their menstrual cycles as this period has a relative reduced hormonal effect on the pattern of enhancement and temporal resolution i.e. the least false-positive enhancement.