Bevacizumab-induced small bowel perforation in a patient with breast cancer without intraabdominal metastases.

A 53-years-old woman presented with sudden abdominal pain. One year before, she was diagnosed an inflammatory ductal carcinoma of the left breast (T3N0M0) and received 6 cycles of epirubicin and cyclophosphamide followed by 9 cycles of paclitaxel. A radical left mastectomy with lymphadenectomy was performed. On histopathology, the invasive ductal carcinoma was poorly differentiated, histological grade III without lymphovascular emboli, expressing E-cadherin, with negative hormone receptors status and no HER-2 overexpression. The final staging after chemotherapy was pT3N1M0, necessitating an adjuvant radiotherapy. Four months postoperatively, a CT-scan revealed liver and lung metastases and chemotherapy combining gemcitabine, oxaliplatin and bevacizumab was started for 13 days when she suddenly developed severe abdominal pain. A CT-scan showed a pneumoperitoneum. She had a median laparotomy confirming the diagnosis of peritonitis by digestive perforation without ovarian, uterine, lymphatic, or peritoneal carcinomatosis. Assessment of the totality of the gastrointestinal tract showed two distinct punched out perforations of the small bowel, without macroscopic signs of tumor or metastases: one on the jejunum at 50 cm from the Treitz and the second at 10 cm of the end of the ileum. Small bowel resection with jejunojejunostomy and a lateral ileostomy were performed. Regarding the macroscopical pathological findings, the mucosa showed an ulceration measuring of 1 cm without tumor. On microscopy we found a tranparietal neoplastic infiltration. Vessels were morphologically normal with tumoral cells' morphology and architecture identical to the primary breast carcinoma. Chemotherapy was not reintroduced after surgery and the patient died on the 57th postoperative day.