Granular cell tumor (Abrikossoff's tumor) of the labium majus: a case report

Granular Cell Tumor (GCT) is an uncommon, benign tumor of neural origin resembling Schwann cells. It is more common in females and blacks. Head and neck regions are the most sites involved by the tumor, but it can occur in any part of the body. Vulva, ovary and cervix in females and scrotum in males can present GCT. The importance of this tumor is potential malignant transformation in rarity. Total excision is the choice treatment for GCT because of probability of recurrences. In this article, we described a case of granular cell tumor of the labium majus in a 21-year old lady, from southwest of Iran. Subsequent investigations confirmed positive results for S100 protein and neuron specific enolase, but Periodic Acid Schiff (PAS) staining was negative. Our findings confirmed neural origin for GCT. Introduction Granular Cell Tumors (GCTs), neoplastic skin and soft tissue lesions [1], were initially described by Weber in 1854 [1,2]. They were also described by Abrikissof in 1926 [3]. They are uncommon, benign tumors of neural origin resembling Schwann cells [4], which occur in less than 0.1% of surgical specimens [1]. The Schwann cell origin of GCT was reported in the 1960’s [2]. Till 1999, approximately 400 cases of GCTs had been reported in the literature, that vulvar involvement had accounted for 7-16% of this [4]. There is a female predominance [5,6]. The average age of presentation is 40-50 years, but the tumors may arise in children [5]. The most common sites involved are the head and neck regions, although GCTs have been found in all areas of the body. GCTs of the female genital region have been documented to occur on the vulva, the ovary, and the cervix [1]. GCTs generally have the following gross characteristics: small size (<5 cm), firm texture, whitish color, lack of encapsulation, and submucosal or subcutaneous location [1]. Herein, we described a case of granular cell tumor of the labium majus in a 21-year old lady. Case presentation The patient was a 21-year-old lady, single, from southwest of Iran, referred to us with complaint of presence of a mass on the vulva. She described that it developed 2 years ago as a small-sized lesion, evolved to a large mass during 1 month after the initial appearance. After this significant growth, it has not had any noticeable change in the size. She also complained of a little pain and pruritus in its surface. The patient did not have any history of trauma and infection in involved region prior to appearance of the lesion. She did not describe a history of such lesion in her family. On physical examination, there was a firm, grayish yellow-colored tumoral lesion, 3×2×2 cm in diameter, in left labium majus with welldefined boarder (Figure 1). It was not tender in palpation. Other clinical findings were normal, and we did not find any similar lesion in other region. A deep sample of this, 3×4×6 mm in diameter, was biopsied with differential diagnoses of adnexal tumors, fibroma and calcified epidermal cyst. Her routine laboratory tests were in normal limit. The pathological findings revealed involvement of dermis with a neoplastic tissue composed of cords and nests of tumoral cells with abundant granular eosinophilic cytoplasm and small round central nucleus, suggestive for the diagnosis of granular cell tumor (Figures 2 and 3). Subsequent investigations confirmed positive results for S100 protein and neuron Correspondence to: Dr. Farzaneh Alamshahi, Emam Khomeini Hospital, 61335, Ahvaz, Iran P.O. Box: 61335 – 4156, Fax: +986113381110; E-mail: dr.alamshahi@yahoo.com