Primary extra-uterine and extra-ovarian mullerian adenosarcoma: case report and literature review

BACKGROUND: Extra-uterine mullerian adenosarcomas have varying biological behaviours depending on the presence of endometriosis or sarcomatous overgrowth. These behaviours manifest according to the tumours’ histological characteristics and sites of origin. The best treatment and oncologic outcome have not been clarified because only a few cases of extra-uterine and extra-ovarian adenosarcoma have been described in the literature. Here, we report a case of primary peritoneal adenosarcoma with sarcomatous overgrowth and review all reported cases of adenosarcomas arising outside of the uterus and outside the ovaries to identify the best treatment options and clarify outcomes. CASE PRESENTATION: A 79-year-old woman was referred to our Department with an abdominal mass resembling a fibroid with a haemorrhage. Her gynaecological history was negative. A transvaginal and transabdominal ultrasound examination revealed a multicystic mass resembling an ovarian tumour arising from the pelvis and extending up to the abdomen. At laparotomy a peritoneal mass arising from Douglas peritoneum was resected. The uterus and adnexa appeared normal, and a supra-cervical hysterectomy with bilateral salpingo-oophorectomy was performed. No macroscopic residual disease was present. Final pathology diagnosed a malignant peripheral nerve sheath tumors with divergent differentiation. Four weeks later a new, multicystic mass was found. Due to the progressive poor condition, the patient died four months after diagnosis. Histological slides were reviewed by external expert pathologists and the final diagnosis was of extra-genital adenosarcoma with sarcomatous overgrowth. Furthermore, we also collected and analysed articles written in English regarding extra-uterine and extra-ovarian adenosarcomas published between January 1974 and October 2016. PubMed was used as a database for this search. Clinical and pathological characteristics, treatments and outcomes were assessed. CONCLUSIONS: Only 41 cases has been reported in literature. Previous endometriosis and sarcomatous overgrowth showed an inverse effect on prognosis. Endometriosis was confirmed to have a positive effect on disease free survival Complete surgical resection is the mainstay of treatment. A worldwide registry is urgently required to collect data to standardize treatment and to obtain reliable data on prognosis.