Uncommon Location of Lipoma: Extraluminally Vagina

Abstract

Background: Lipomas are defined as a soft mass of well-differentiated adipose cells among mesenchymal tumors. Considering the localization of lipomas, these masses are commonly seen in subcutaneous tissue. The female reproductive tract is a rare site for development of lipomas and clinical findings appear depending on the size and localization. The connection of the mass with the vagina lumen causes different clinical findings. Intraluminal tumors protrude and arise from the vulva, while extraluminal tumors lead to perineal swelling. This case describes clinical, ultrasonographic, histological examination, and surgical management of extraluminal vaginal lipoma.

Case: The present study reports a case of extraluminal vaginal lipoma in a 10-year-old Pitbull crossbred presented with anamnesis of a protruded tissue from the vulvar lips and dysuria following 6-month swelling in the perineum. Clinical examination revealed that the swelling was obvious and localized mostly on the lower left side of the perineum and the vaginal mucosa was protruded from the vulvar lips due to a mass. By vaginal palpation, the mass was not associated with the vaginal mucosa. The mass was located in the perivaginal region and transvaginal ultrasonography revealed a hypoechogenic mass. Based on clinical and ultrasonographic findings, surgery was recommended. The mass was adherent to the serosa of the vagina and it did not enclose the vaginal mucosa. Excision of mass was performed with careful blunt dissection avoiding any urethral disruption and periurethral tissues. After the mass was determined to be extraluminal, there was no need for excision of the vaginal tissue with the mass during operation. Using histopathological examination the mass was identified as a lipoma composed of adipocytes. In addition, ovariohysterectomy was not recommended following the diagnosis of vaginal lipoma.

Discussion: Lipomas uncommonly can be localized in unpredicted rare areas such as vagina and vulva in older bitches. Although the majority of reported benign tumors in dogs recommend the surgery, medical treatment including the steroid injections is the other option to limit the lipomas. Considering the vaginal tumors, the surgical approach is also planned as laparotomy since leiomyomas are more common than lipomas. This approach partially results from the adherence of tumors to vaginal tissue. In addition, the location of the mass together without the adjacent tissue damage depending on whether it is intraluminal or extraluminal would make complete tissue removal. In previous reports, while symptoms such as perineal hernia of the lipoma were emphasized, the connection of the lipoma with the vaginal lumen was not evaluated as a significant factor determining the surgical approach. The mass was not connected to the vaginal mucosa and it was determined as extraluminal lipoma in the present study. Mass excision was performed by blunt dissection, avoiding urethral disruption and periurethral tissues. Unlike the most common approach in leiomyomas, this report did not require a total vaginectomy to remove the mass from the vagina. The ovariohysterectomy was not needed to be performed in the present study as in intraluminal vaginal tumors. It was believed that adhesions of lipoma with vaginal lumen is a determining factor in the combination of surgical techniques such as episiotomy and/or ovariohysterectomy. Lipomas should be considered among the tumors in the vaginal region of dogs brought with the complaint of swelling in perineum and protrusion of vaginal tissue.