Spindle Cell Rhabdomyosacoma of Uterus: A Case Study
A 76-year-old woman, gravida 3, para 2, presented with intermittent lower abdominal pain of increasing severity. The patient reported a 10 kg weight loss with associated anorexia and constipation for approximately six months. Physical examination revealed abdominal tenderness and a fixed lower abdominal mass at roughly six months in gestational size. Abdominal and pelvic ultrasonography showed a multilobulated solid and cystic mass in the pelvic cavity. A computerized tomography scan of the abdomen and pelvis demonstrated a 16×10×8 cm lobulating-contoured and heterogeneously-enhanced mass occupying the lower abdomen and pelvic cavity. Neither the uterus nor both ovaries were identified (). Serum levels of tumor markers, with normal values in parentheses, were as follows: cancer antigen 125, 101.2 U/mL (<35 U/mL); cancer antigen 19-9, 4.8 U/mL (<30 U/mL). An exploratory laparotomy was performed given the high-suspicion for an ovarian tumor. Intraoperatively, a yellowish, hard, friable, 20×15×7 cm mass had replaced the right lateral uterine wall and had adhered to the colon, rectum, and appendix. The right ovary was not recognized, but the left ovary and both fallopian tubes appeared normal. Tumor debulking and subtotal hysterectomy with bilateral salpingo-oophorectomy were performed. The tumor grossly occupied the entire right myometrium and was bulging into the endometrial cavity. The cut surface of the tumor had a variegated appearance, including components of greyish soft, whitish fish-flesh, and yellowish myxoid with small cystic changes (). Wide areas of hemorrhagic necrosis were also noted. Microscopic findings exhibited highly cellular and necrotic tumor consisting of bundles or fascicles of spindle cells in a myxoid stroma (). Rare rhabdomyoblasts containing eccentric nuclei and deeply eosinophilic cytoplasm were observed (). Pleomorphic tumor cells were mixed with spindle cells in small areas. Mitotic figures were frequently counted with more than 100 mitotic figures per 10 high power fields. Right ovarian tissue was identified in the fibrous tumor capsule without direct invasion of tumor cells. Immunohistochemical staining showed diffuse positivity of tumor cells with myoglobin (), myo-D1, desmin, and vimentin. No stains for smooth muscle actin, pan-cytokeratin, epithelial membrane antigen, or estrogen receptor were postive. The patient refused further treatment and died of disease three months after diagnosis.