Ischemic Colitis in a Patient Treated with Tamoxifene and Exemestane for Breast Cancer

In November 2011 a 64 years old woman came to our emergency room, presenting clinical, blood and consistent imaging features with intestinal infarction, the symptoms having started 18 hours before.The patient did not show any emboligen disease. In her medical history: mastectomy for an early stage breast cancer, treatment with tamoxifen then exemestane, right hip replacement, endoscopical and bioptic diagnosis of ischemic colitis or inflammatory bowel disease.The patient underwent an emergent laparotomy, which revealed multiple and confined necrotic patches in her terminal ileum and colon. Because of fast and progressive hemodynamic worsening, due to onset of septic shock, only a diverting ileostomy could be performed. After defunctioning ischemic and necrotic bowel, restoring intravascular volume, giving wide spectrum antibiotics, correcting metabolic acidosis and having reached a stable hemodynamic balance, it became possible to carry out the second surgical look. Extension of ischemia could be excluded and an ileocolic resection, including the descending colon, was performed, leaving the sutured sigmoid stump in the pelvis and the ileostomy previously done. Three and a half months later bowel transit has been restored by an ileum-sigmoid anastomosis, followed by a fast recovery.Because of absence of emboligen diseases and considering the patchy necrotic lesions, the cause is likely to be a thromboembolic occlusion of medium and small arterial branches of the superior and inferior mesenteric arteries. The vasculitic etiology has been excluded by pathological findings, lack of clinical symptom and by blood immunological tests.Hence we hypothesized a thrombotic stenosis, due to the long lasting treatment with tamoxifen (3.5 years), critically deteriorated by the therapeutical switch with exemestane (8 months before), as the etiologic factors.It is well known indeed as those drugs can rise the thromboembolic risk, but it is referred only to cerebrovascular and cardiac ischemia. Until the date, there are no reports about mesenteric ischemia related to neither tamoxifen nor exemestane.