e19647 Background: otally implanted venous access systems (portacath) are increasingly used in cancer patients in order to make the application of chemotherapy for patients more comfortable and safer. Nevertheless these portacaths are associated with short– and long-term complications. These vary between different types of malignancies. Complication rates in breast cancer patients have not yet been analyzed broadly. Methods: We performed a retrospective analysis at the universitiy hospital Frankfurt, Germany. Records from 405 breast cancer patients who had received an ECG- guided portacath insertion from years 2003 to 2009 were reviewed to evaluate risk factors for port associated complications. Two different insertion techniques were used: surgical cut down to the cephalic vein or if not possible direct puncture of the subclavian vein. The device was placed on the fascia pectoralis after ECG-guided positioning of the catheter tip. All patients were followed through December 2009 or until death, catheter failure, or catheter removal upon completion of chemotherapy. Beside clinical tumor parameters disease specific events have been evaluated. Results: Of 405 breast cancer patients 9 were excluded because of incorrect portacath insertions. Among the remaining 396 patients the most frequent complication was thrombosis (9.8%). Surgical complications were infrequent with catheter leakage (0.8%) and pneumothorax (0.5%). We found no significant correlations between the rate of thrombosis and several different clinical variables (primary vs. metastatic disease, tumor size, lymph node status, and histological grading). Moreover no differences were found regarding to the two applied insertion techniques or the chest side in which the portacath was placed. Interestingly, the rates of thrombosis were lower in patients older than 50 years (7.1% vs. 14.0%; p=0.037). Conclusions: The thrombotic complication rate in breast cancer patients is rare. We found younger age as the only patient-related risk factor for the development of port-related thrombosis. No significant financial relationships to disclose.