Case Report
Giant Perineal Leiomyoma Incidentally Manifested at a Recent Episiotomy Site: Case Report Luiz Gustavo Oliveira Brito, MD*, Luciana Falc~ao Motoki, MD, Pedro Sergio Magnani, MD, Maurıcio Mesquita Sabino-de-Freitas, MD, PhD, Gla ucia Aparecida Magnani Landell, MD, and Silvana Maria Quintana, MD, PhD From the Division of Urogynecology, Gynecological and Pelvic Reconstructive Surgery (Drs. Oliveira Brito, Falc~ao Motoki, Magnani, Sabino-de-Freitas, and Magnani Landell), and the Division of Maternal-Fetal Medicine (Dr. Quintana), Department of Gynecology and Obstetrics, Faculty of Medicine of Ribeir~ ao Preto, S~ ao Paulo University, S~ao Paulo, Brazil.
ABSTRACT Benign leiomyomas are common soft tumors, arising especially in the female genital tract; unlike uterine leiomyomas, they rarely occur in perineal regions. They can develop wherever smooth muscle is present. Herein is reported the case of a large perineal leiomyoma in a 36-year-old woman who noted a palpable mass close to the rectum 1 year after she had delivered vaginally, in the same region of as a mediolateral episiotomy. Complete surgical excision was performed. Histopathologic findings were compatible with benign leiomyoma. At postoperative follow-up, no signs of anal dysfunction were noted. There was no pathologic correlation between formation of the leiomyoma and the episiotomy despite a possible association between the presence of fibrosis and development of leiomyomas, which was found during a literature review. Microarray analysis will be necessary to elucidate this hypothesis. Journal of Minimally Invasive Gynecology (2011) 18, 267–269 Ó 2011 AAGL. All rights reserved. Keywords:
Episiotomy; Perineal leiomyoma
Perineal leiomyomas are extremely rare monoclonal mesenchymal tumors, with an incidence of 3.8% of all benign soft tissue tumors [1]. Usually, they have a slow proliferative behavior, with absence of nuclear atypia. However, larger lesions can masquerade as other superficial perineal tumors such as epidermoid cysts, Bartholin gland abscesses, and perineal abscesses. Malignant conditions can also occur in this region, especially if tumor growth is rapid. There are some hypotheses that support the association between myoma development and the production of collagen and extracellular matrix by fibroblasts. In microarray specimens of uterine leiomyoma, activation of genes was involved in the formation of extracellular matrix, collagens, proteoglycans, and elastin that integrate the connective tissue between cells. Herein is The authors have no commercial, proprietary, or financial interest in the products or companies described in this article. Corresponding author: Luiz Gustavo Oliveira Brito, MD, Hospital das Clınicas da FMRP-USP, Ave Bandeirantes 3900, 8th Floor, Monte Alegre, Ribeir~ao Preto, S~ao Paulo, Brazil 14049-900. E-mail:
[email protected] Submitted September 28, 2010. Accepted for publication December 16, 2010. Available at www.sciencedirect.com and www.jmig.org 1553-4650/$ - see front matter Ó 2011 AAGL. All rights reserved. doi:10.1016/j.jmig.2010.12.010
reported the case of a palpable large perineal mass in the episiotomy region after a vaginal delivery, along with possible pathophysiologic correlations.
Case Report A 36-year-old woman (gravida 6, para 4, abortus 2) was referred to our service because of perineal tenderness and local pain since she had undergone a right-sided mediolateral episiotomy 1 year previously. She also noted a palpable soft mass in the same region. Vaginal birth occurred without problems. The patient had no history of drainage of perineal abscesses at that time. No urinary, intestinal, or gynecologic symptoms were reported. At physical examination, palpation revealed a cystic mass that extended from the right labia majora to the posterior gluteal region (Fig. 1). Vaginal examination revealed a mobile mass in the right vaginal wall that extended to the right pouch of Douglas; rectal inspection demonstrated no invasion. Transperineal ultrasonography demonstrated an anechoic, rounded, multiseptated, vascularized mass measuring 15 ! 6.5 ! 7.5 cm (volume, 352 cm3), with retrotumoral shadowing and well-defined precise limits, located in the right
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Fig. 1. At physical examination, palpation revealed a cystic mass that extended from the right labia majora to the posterior gluteal region.
perineal region without compromising the rectum, 1.5 cm from its serosa. The right-sided Bartholin gland was not defined. At surgery, a lobulated, well-demarcated, benign mass was noted, without invasion of surrounding tissues (Fig. 2). Frozen-section assessment revealed a benign mesenchymal tumor. The right Bartholin gland was also removed, with no mitotic abnormalities. Histopathologic analysis revealed a benign stromal fusocellular neoplasm surrounded by fibrotic areas, with absence of necrosis, nuclear pleomorphism, or mitotic images. Immunohistochemistry demonstrated strong positivity for smooth muscle actin and desmin (Fig. 3A and B); CD117, CD34, and S100 were negative for this tumor, confirming its origin as a perineal leiomyoma. The patient was discharged without any other treatment. Immediate and late postoperative follow-up demonstrated no recurrence of the mass. Discussion Perineal and superficial leiomyomas have been reported [2] mimicking Bartholin glands [3] and perineal hernias
Fig. 2. At surgery, a lobulated, well-demarcated, benign mass was noted, without invasion of surrounding tissues.
Fig. 3. Immunohistochemistry demonstrated strong positivity for smooth muscle actin (A) and desmin (B).
[4]. Usually, transperineal or transvaginal ultrasonography, pelvic computed tomography, and pelvic magnetic resonance imaging are used for differential diagnosis of such tumors. However, the Bartholin gland could not be identified because of the large size of the perineal mass, which led to the clinical suspicion that at surgery a complex Bartholin gland abscess would be observed. No pathologic changes were observed in this structure; moreover, cystic adenoid adenocarcinoma is seldom observed in the Bartholin gland [5]. A positive aspect of the surgery was the well defined margin between the perineal mass and the rectum, which was correlated with normal postoperative defecation during follow-up. A case report from Koc et al [3] described restoration of normal local anatomy after resection of a large perineal leiomyoma. No description of this soft benign tumor in an episiotomy incision was found in an extensive PubMed review of the literature using several descriptors including episiotomy, tumors, fibrosis, perineal leiomyoma, and vaginal leiomyoma. Scar endometriomas [6], granulomas, neuromas, and carcinomas were extensively described in episiotomy
Oliveira Brito et al.
Giant Perineal Leiomyoma at an Episiotomy Site
incisions, and probably this association is incidental because it could not be explained at histopathologic analysis. Despite the lack of etiopathology to justify its origin, some molecular researchers using microarray analysis of leiomyomas have suggested a model of myoma development based on an abnormal response to tissue repair, resulting in disordered healing and formation of an altered extracellular matrix [7]. These studies discussed the role of extracellular matrix, transforming growth factor beta, and collagen structure in myoma formation, linking myomas to keloids. Dermatopontin, a collagen-binding protein, was consistently reduced in uterine leiomyomas [8], and the use of collagen inhibitors such as tranilast experimentally arrested the proliferation of uterine leiomyoma cells at the G0/G1 phase [9]. Another uncommon behavior was observed in this benign tumor; rapid growth is not an ordinary characteristic of this group of leiomyomas. There is a group of mitotically active leiomyomas that have a natural benign course, with some cytologic atypia (smooth muscle tumors of uncertain malignant potential) [10]. However, no mitotic figures and no metastatic leiomyomas were observed in this patient. The hypothesis of a gastrointestinal stromal tumor was also investigated.
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