A mature cystic teratoma of the omentum occurred in a 37 years old woman, who had an appendicectomy at the age of 8. This extragonadal teratoma contained a predominant mucinous glandular pattern of borderline malignancy, responsible for pseudomyxoma peritonei. Ovarian biopsies had only shown surface mucinous deposits at the time of the first laparotomy but two years later ovarian mucinous cystadenomas of borderline malignancy appeared. The patient developped intestinal obstruction, surround by mucinous retractil material and died four years and an half after initial diagnosis. This case is, to our knowledge, the first pseudomyxoma peritonei occurring from an extragonadal teratoma, the events chronology suggesting the secondary nature of the ovarians tumors.

A mature cystic teratoma of the omentum occurred in a 37 years old woman who had an appendicectomy at the age of 8. This extragonadal teratoma contained a predominant mucinous glandular pattern of borderline malignancy, responsible for pseudomyxoma peritonei. Ovarian biopsies had only shown surface mucinous deposits at the time of the first laparotomy but two years later ovarian mucinous cystadenomas of borderline malignancy appeared. The patient developed intestinal obstruction, surround by mucinous retractile material and died four years and an half after initial diagnosis. This case is, to our knowledge, the first pseudomyxoma peritonei occurring from an extragonadal teratoma, the events chronology suggesting the secondary nature of the ovarian tumors.

The diagnosis of uterine haemangiopericytoma is still a matter of debate. The existence of haemangiopericytoma must be proven on the basis of classical histology, ultrastructure histology and immunohistochemical analyses. The diagnosis, even when apparently sure, must nevertheless be proven. We described two cases emphasizing the clinical and laboratory features of uterine haemangiopericytoma. Progress in nuclear magnetic resonance imaging, ultrastructural analysis and immunohistochemistry should help in confirming the diagnosis of haemangiopericytoma. Highly vascular leiomyoma or low malignity grade leiomyosarcoma have been mistakenly identified as haemangiopericytoma.