Cytoreductive surgery plus intraperitoneal hyperthermic perfusion is an effective treatment for metastasized malignant mixed mesodermal tumours (MMMT)—report of six cases

Background. Malignant mixed mesodermal tumours (MMMT) of the female genital tract are rare and heterogeneous malignancies that impart grim prognosis. These tumours are characterized by an admixture of malignant epithelial and stromal elements comprising carcinomatous and sarcomatous neoplastic cells. Thus far, almost 350 cases of MMMT have been recorded in the international medical literature. Due to its rarity, there is no agreement on the best treatment strategy in women with metastasized MMMT. Methods. Six women (mean age 59 years) with metastasized MMMT defined to the peritoneal cavity have been treated by cytoreductive surgery plus hyperthermic peritoneal perfusion plus postoperative adjuvant chemotherapy. All patients have been pre-treated by surgery for primary tumour and one by systemic chemotherapy. As cytostatics for hyperthermic peritoneal perfusion, we have used Mitomycin in a dosage of 18 mg/m2 plus Melphalan in a dosage of 25 mg/m2. As adjuvant treatment CDDP 40 mg/m2/dl, Mitomycin 7 mg/md2/dl and Ifosfamid 100 mg/kg 24 h/dl was applicated via intraaortic catheter three times with a treatment free interval of 3 weeks. Results. A complete cytoreduction without remnant tumour formations in the peritoneal cavity could be carried out in all six patients. The postoperative course was uneventful in all cases except for one where a spontaneous small bowel perforation and prolonged gall secretion had to be treated by re-operation. One patient died 4 months later by pneumonia without evidence of disease. Four patients are without evidence of disease after 2, 4, 14 and 19 months, whereas one patient developed liver metastases after 9 months still treated by systemic chemotherapy. Conclusion. Complete cytoreduction plus hyperthermic peritoneal perfusion plus adjuvant chemotherapy seems to be an effective treatment for recurrent or metastasized MMMT. Further studies have to define the value of this new treatment strategy for this rare tumour entity.