Carcinosarcoma of the colon: a rare cause of colovesical fistula.

Carcinosarcomas are relatively rare tumors composed of both carcinomatous and sarcomatous components. The most common sites involved by this tumor are the head and neck, respiratory tract, uterus, ovaries, and fallopian tubes. Within the gastrointestinal tract this tumor most often occurs in the esophagus, followed by the stomach. Carcinosarcomas are very aggressive tumors associated with a poor prognosis. The first case of carcinosarcoma of the colon was reported in 1986. The case reported here is the only one involving an associated colovesical fistula.

Ischemic duodenal ulcer, an unusual presentation of sickle cell disease.

Sickle cell disease is caused by molecular abnormalities in the formation of hemoglobin, leading to pain crisis from recurrent vascular occlusion by sickled hemoglobin. Impaired flow in the microvasculature can lead to ischemia, tissue infarction and ulceration. Abdominal pain, a common complaint in sickle cell disease, can be due to an uncommon etiology, ischemic duodenal ulceration. This is due to primary mucosal infarction caused by sickling, leading to poor healing of infarcted areas. Prompt endoscopic and/or urgent surgical intervention should be considered, particularly if anticoagulation is an issue, as proton pump inhibitor use is ineffective in healing this type of ulcer.