Magnetresonanz-Mammographie zur Diagnostik von Fruh- und Spatrezidiven nach organerhaltender Brustkrebstherapie

Background: To examine the value of MR-mammography in the assessment of early and late recurrence after breast conserving therapy. Methods: 67 patients treated conservatively for breast cancer were subjected to 84 MR-mammographies between 1 month and 14 years after end of therapy using a 1,5 T MR unit and a double breast coil. In all patients a dynamic examination after the injection of contrast medium was performed with a 2 D-FLASH sequence. Signal intensity measurements were obtained in focal enhancing lesions, the irradiated and the non-irradiated breast parenchyma. Results: 7 local recurrences, 1 chest wall recurrence, and 2 contralateral carcinomas were detected and histologically proven. All 10 lesions showed an increase of signal intensity > 75% one minute after injection of contrast medium. In all 27 patients investigated in the first year after end of radiation therapy an intensified enhancement of the irradiated parenchyma was observed, but only in 2 patients the measurements showed an increase > 75% one minute after injection of contrast medium. When examined three months later all posttherapeutic changes showed a marked reduction of enhancement. Conclusion: Already in the first year after end of therapy magnetic resonance imaging can improve diagnostic accuracy in the assessment of breast cancer recurrence and helps to reduce the number of unnecessary biopsies. More than 12 months following end of therapy, no problems arose in distinguishing tumor recurrence from therapy induced changes.