Introduction
Ovarian cancer causes more deaths per year than any other cancer of the female reproductive system. Carcinosarcoma of the ovary is a rare, highly aggressive neoplasm characterized by the presence of both carcinomatous and sarcomatous components. It is also called as malignant mixed mesodermal tumors [MMMTs], malignant mixed mullerian tumors or sarcomatoid carcinomas. It accounts for <1% of all ovarian tumours. Even after evolution of chemotherapy with introduction of platinum agents, the survival still seems to be poor and hence data regarding an optimal regimen and its impact on patient’s survival remains inconclusive. 1, 2
Case Report
A 62 year old female came with history of bleeding per vagina and fullness over abdomen since 20 days. On complete examination she was poorly built and nourished with a palpable mass in the lower abdomen. CECT showed a right ovarian solid cystic necrotic mass occupying the whole of pelvis. She underwent a total abdominal hysterectomy with partial omentectomy. The left adnexa showed an irregularly enlarged ovarian mass measuring 13x7x5cm. Cut surface was solid and cystic with areas of haemorrhage and necrosis. Serous fluid was drained out.
Histological examination showed a high grade biphasic neoplastic lesion composed of an admixture of epithelial and mesenchymal elements. Epithelial element showed high grade undifferentiated tumor cells arranged in sheets, trabeculae and cords exhibiting moderate pleomorphism, ill-defined cytoplasmic borders, vesicular nuclei with finely dispersed chromatin. Focally glandular differentiation was made out. 5-6mitoses/HPF seen. Mesenchymal component in the form of atypical sarcomatous spindle shaped cells along with heterologous differentiation towards cartilage was made out. Cartilage showed high cellularity and cytological atypia. Multinucleate giant cells were seen. Areas of necrosis and haemorrhage present. No vascular invasion noted.
Figure 2
Epithelial component showing undifferentiated cell in sheets and trabecular (Hand E & 40x).
Figure 3
Mesenchymal component showing atypical spindle cells with areas of cartilaginous differentiation (Hand E, 40x).
Figure 4
Heterologous cartilaginous differentiation showingatypia; Multinucleate giant cell (arrow) (Hand E, 40X).
Figure 5
Cell block preparation showing atypical malignant cells in clusters andtrabeculae. (H & E, 40x).
Cell block study for Ascitic fluid was positive for malignancy although omentum sent for HP examination did not show any macroscopic or microscopic deposits.
So the final diagnosis of FIGO stage III- Carcinosarcoma of ovary with heterologous element was made. Patient did not receive any chemotherapy despite being advised yet the patient was keeping well 10 months post-surgery.
Discussion
Carcinosarcomas are tumours usually arising from the uterus. Their occurrence in the ovary is a rarity. 3 The pathogenesis of carcinosarcomas remains under debate but immunologic studies and molecular studies have suggested that three main theories: 1) The collision theory- where the two tumour types collide and exist as two independent tumours. 2) The combination theory- where the two components arise from a common stem cell precursor. 3) The conversion theory- where the sarcomatous element arises from the carcinomatous element during the tumour evolution. 4 It usually presents in elderly postmenopausal women. Symptoms include pelvic/ abdominal pain, early satiety, bloating, abdominal distension and other GI complaints.
Patients' performance status at presentation is usually worse. They present in the advanced disease stage and these patients have a grim prognosis with median survival rate of 17-27 months. After reviewing the prognostic factors patients with heterologous components said to have worse prognosis. But this no longer holds good. Also, other histologic features like mitotic index, grade of the tumour are no longer associated with the ability to predict metastasis. However, some studies have shown that the tumour's epithelial elements may have predictive outcome.5 Usually FIGO stage I and II have good prognosis while stage III and IV have worse prognosis owing to the suboptimal debulking of the tumor during surgery. 6 So the residual disease following surgery is an important prognostic factor which can be analysed by follow-up CA-125 levels. IHC can be used to identify the biphasic population but the studies on overexpression of p53 and Ki67 index as prognostic indicators has not yet shown statistically significant results. 7, 8
Conclusion
Owing to its poor prognosis, early diagnosis whenever possible, optimal debulking of the tumor during surgery and follow up of the patient for residual disease becomes important. Despite the aggressive treatment of surgery and chemotherapy it carries a significantly increased risk of death. The risk, rarity, prognosis of this tumor emphasises the need for collaborative, prospective studies targeted to better understand the molecular changes and the need to design better treatment regimens to improve patient’s survival.
