A Case of Leiomyosarcoma of Vaginal Vault in a Post-hysterectomy Patient

INTRODUCTION

Leiomyosarcoma usually arises de novo from uterine smooth muscle, although it may rarely arise from a preexisting leiomyoma.¹ They are usually accompanied by pain, sensation of pressure, and abnormal uterine bleeding (AUB). Rapid enlargement of fibroid or rapidly increasing pain may be a symptom too. Few patients may have features of metastatic disease too. Clinically, it is impossible to differentiate leiomyosarcoma from large fibroid. Uterine curettage is diagnostic in 10–20% of cases only.² In many cases, it is only diagnosed after surgery.

CASE DESCRIPTION

The patient aged 62 years came to the outpatient department (OPD) with a complaint of pain in abdomen for the last 3 months. She is P2L2, post-menopausal for the last 12 years. She had a history of total abdominal hysterectomy (TAH) + bilateral salpingo-oophorectomy (BSO) 10 years back due to AUB. However, detailed OT note or biopsy report was not available. Before coming to our institute, she consulted outside for this pain in abdomen, and clinical examination revealed a pelvic mass approximately 8 × 6 cm above the vaginal vault. It was solid variegated, smooth, and well defined.

She had an fine needle aspiration cytology (FNAC) of the mass outside and the report suggested spindle cell carcinoma.

On admission, we did contrast-enhanced computed tomography (CECT) imaging and it showed a solid well-defined mass seemingly attached to vault. CECT did not suggest any metastatic deposit anywhere and we planned for laparotomy and proceed.

Intraoperatively an approximately 8 × 8 cm² sized solid mass was seen arising from vaginal vault (Fig. 1). Uterus and bilateral ovaries were absent and all other intra-abdominal organs were normal. The mass was removed and the patient was discharged postoperatively on day 5.

Subsequent holoprosencephaly (HPE) report came out to be leiomyosarcoma with areas of patchy necrosis (Fig. 2). Mitotic count was 4/10 microscope high-power field (HPF) (Fig. 3). immunohistochemistry (IHC) profiling showed a high uptake of smooth muscle antigen (SMA) (Fig. 4). The patient is planned for follow-up.

Fig. 2: Areas of necrosis and hemorrhage

Fig. 3: One tripolar (atypical) mitotic figure

Fig. 4: SMA-positive IHC for leiomyosarcoma

DISCUSSION AND CONCLUSION

Leiomyosarcoma is a malignant smooth muscle cell tumor and is a rare form of malignancy with poor prognosis.³ It accounts for 2–5% of all malignancies. Leiomyosarcoma is the most common type of sarcomas accounting for 25–36% of uterine sarcomas.⁴ It is most commonly seen in involuntary muscles, uterus, stomach, intestine, retroperitoneum, walls of blood vessels, and skin. Leiomyosarcoma has a primary site of origin anywhere in body where there is blood supply. Regarding prognosis, good prognostic tumors were <10 cm diameter, <20 mitoses/10 HPF, negative for Ki-67, and positive or negative with Bcl-2 staining.⁵ GeDDiS trial concluded that doxorubicin should be the primary chemo of choice for advanced soft tissue sarcoma. Still the role of adjuvant chemotherapy is contentious and evidence suggests minimal or no impact on survival. The overall 5-year survival rate is around 75% in stage 1.⁶ In this case, her previous TAH BSO OT note and HPE report were absent. Due to that factor, it can be assumed that the mass has originated from the smooth muscle of vaginal vault. Overall, there are very few cases reported where leiomyosarcoma has originated from vaginal vault without any history of previous uterine leiomyosarcoma.

REFERENCES

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