Case report of undifferentiated endometrial sarcoma in association with osteoclast-like giant cells

Abstract

We describe the clinical, gross and microscopic features of undifferentiated uterine stromal sarcoma associated with osteoclast-like giant cells. A case of low-grade endometrial stromal sarcoma is already described in association with osteoclast-like giant cells; however, the current case differs in that the tumor was a high grade and did not show any evidence of smooth muscle or epithelioid differentiation and was shown to be strongly positive for CD10 and focally for WT-1 and Inhibin supporting an endometrial stromal origin. The associated osteoclast-like giant cells were abundant, evenly distributed within the tumor and showed strong positivity for CD68. Interestingly, rare (less than 2%) giant cells also showed weak cytoplasmic positivity for b-hCG. The tumor infiltrated deep into the myometrium and had marked lymphovascular invasion. Although the regional lymph nodes and peritoneal washings were negative, the lesion showed a highly aggressive clinical course. Despite treatment, the tumor disseminated within the abdominal cavity and lungs and ultimately led to the patient's demise within 9 months of the diagnosis.

Figure 1

(a) MRI (T1 weighted, after Gadolinium injection): Enlarged uterus with central hypodense area. (b) ThinPrep Pap smear showing numerous spindle cells with marked anysocytosis, anisonucleosis and chromatin condensation. The background shows granular tumor diathesis and blood (Pap, 400x). (c) ThinPrep Pap smear: Multinucleated giant cells in association with single spindle and more epithelioid appearing malignant cells (PAP, 400x). (d) Hysterectomy gross specimen showing anterior and posterior endometrial cavities occupied with tumor with central hemorrhagic area. (e) Histologic sections showing high-grade sarcoma with osteoclast-like giant cells, numerous mitotic figures and individual cell apoptosis (H&E, 200x). (f) High power view of histological sections showing undifferentiated endometrial sarcoma with marked cellular pleomorphism and atypical mitoses (H&E, 400x).