Glomus Tumor of the Oral Cavity: Report of a Rare Case and Literature Review

Brazilian Dental Journal (2019) 30(2): 185-190 http://dx.doi.org/10.1590/0103-6440201902222.indd ISSN 0103-6440 Glomus Tumor of the Oral Cavity: Report of a Rare Case and Literature Review Celeste Sánchez-Romero1 , Maria Eduarda Pérez de Oliveira2 , Jurema Freire Lisboa de Castro2, Elaine Judite de Amorim Carvalho2, Oslei Paes de Almeida1, Danyel Elias da Cruz Perez2 Glomus tumor is a benign neoplasm composed of a perivascular proliferation of glomic cells that resembles the normal glomus body. Usually, it appears as a solitary, symptomatic small blue-red nodule, located in the deep dermis or subcutis of upper or lower extremities of young to middle-aged adults. Cases affecting the oral cavity are very rare, with only 23 well-documented cases reported in the English-language literature. Herein, we present a rare case of glomus tumor of the upper lip, and review the literature of cases involving the mouth. Introduction Perivascular tumors are formed by cells derived from contractile perivascular myoid cells/myopericytes that support blood vessels, including glomus cells. According to the soft tissue tumors classification of the World Health Organization (WHO), these perivascular myoid tumors show more alignment with smooth muscle tumors rather than vascular tumors. They are generically denominated myopericytoma (MPC), with a spectrum including glomus tumor (GT), solitary myofibroma (SMF), and angioleiomyoma (ALM) (1,2). The glomus apparatus is an arteriovenous anastomosis, with thermal regulation function, located at the stratum reticularis of the dermis, mainly in the subungual region, lateral areas of digit and palm of the hands, and on the feet ventral surface (3,4). Glomus cells are small, uniform, rounded cells, with a central nucleus, and amphophilic or pale eosinophilic cytoplasm (5). GT resembles histologically the glomus body, being firstly described by Masson in 1924, possibly derived from modified smooth muscle cells of the glomus body. This tumor is commonly located in areas rich in glomus bodies, usually appearing as a small blue-red nodule, commonly associated with localized tenderness, paroxysmal pain, and sensitivity to cold or tactile stimulation. It occurs more commonly in young or middle-aged adults (6,7). In head and neck region, including the oral cavity, solitary myofibroma and angioleiomyoma are relatively common. However, GT is extremely rare in the mouth. To the best of our knowledge, there are only 23 well-documented cases of GT involving the mouth reported in the Englishlanguage literature (2,3,8-27). The aim of this report is to describe the histopathological and immunohistochemical 1Oral Pathology Section, Department of Oral Diagnosis, Piracicaba Dental School, UNICAMP - Universidade Estadual de Campinas, Piracicaba, SP, Brazil 2School of Dentistry, Oral Pathology Section, Department of Clinical and Preventive Dentistry, UFPE - Universidade Federal de Pernambuco, Recife, PE, Brazil Correspondence: Danyel Elias da Cruz Perez, 4ª Travessa Professor Artur de Sá, s/n, Cidade Universitária, 50740-521 Recife, PE, Brazil. Tel. +55-81-2126-8342. e-mail: Key Words: glomus tumor, immunohistochemistry, oral cavity, review, upper lip. features of a rare case of GT involving the upper lip, and to review the pertinent literature. Case Report A 51-year-old female patient presented with a lightly painful nodule in the upper lip with approximately 6 months of duration. Intraoral examination revealed a submucosal, smooth-surfaced, well circumscribed, and normochromic nodule, which measured approximately 10 mm of diameter. The main clinical diagnoses was pleomorphic adenoma or canalicular adenoma, but mesenchymal benign tumors as neurofibroma, neuroma and angioleiomyoma were also considered. Under local anesthesia, the lesion was excised and the surgical specimen sent for histopathological analysis. Microscopically, hematoxylin-eosin-stained sections showed an encapsulated proliferation of rounded pale eosinophilic epithelioid like cells, with prominent nuclei and inconspicuous nucleoli, which surrounded numerous convolutions of varying sized vessels in a myxoid stroma (Fig.1 A). The fibrous capsule contained numerous blood vessels and small nerve fibers. Within the tumor, some larger vessels presented prominent thickness of the wall forming a nodule of spindle cells that protruded into the lumen (Fig. 1 B). The tumors cells formed two patterns of arrangement, one loose surrounding the larger vessels, and one solid, with dense sheets of tumor cells permeated by many capillary-sized vessels (Fig. 1 C,D). The perivascular concentric layers of rounded clear-eosinophilic cells around larger vessels resembled the histological aspects of the glomus body. Cellular atypia or mitoses were not found. Immunohistochemically, the tumor cells were positive for vimentin, CD34, α-SMA, muscle actin (HHF-35), Braz Dent J 30(2) 2019 h-Caldesmon and negative for pan-cytokeratin (AE1/AE3), CD138, S-100 and desmin (Table 1). Basement membrane material around tumor cells was positive for type IV collagen in a chicken wire pattern (Figs. 2 and 3). Periodic-acid Schiff (PAS) was additionally performed, highlighting the network of basement membrane material (Fig. 3). According to the histopathological and immunohistochemical features, the final diagnosis was of GT. After 18 months of follow up, no recurrences were observed. Discussion Antibody Clone Result Pattern Pan Cytokeratin AE1/AE3 Negative NA CD138 MI15 Negative NA CD34 QBEnd-10 Focally Positive Membranous, 30% of tumor cells Vimentin Vim 3B4 Positive Cytoplasmic, 100% of tumor cells S-100 Polyclonal Negative NA α-SMA 1A4 Positive Cytoplasmic, 100% of tumor cells SpecificMuscle Actin HHF-35 Positive Cytoplasmic, 100% of tumor cells H-Caldesmon h-CD Positive Cytoplasmic, most tumor cells Desmin D33 Negative NA Type IV collagen CIV 22 Positive Pericellular, most tumor cells NA: not applicable C. Sánchez-Romero et al. GT is uncommon, representing less than 2% of all benign soft tissue tumors (5). Most GTs are solitary, small, nodular painful lesions, usually affecting superficial soft tissues of distal extremities of adults on the third to fifth decades. Despite of this, it may occur at any age and location. Only subungual lesions show predilection for women (24). The present case showed similar characteristics, except for its location, in the upper lip¸ where it is very rare. A review of the English-language literature identified only 23 cases Table 1. Immunohistochemical profile of the oral glomus tumor Figure 1. Histopathological features of glomus tumor. (A) At low power magnification, it is observed an encapsulated proliferation of round cells surrounding numerous convolutions of varying sized vessels in a myxoid stroma. The fibrous capsule contained numerous blood vessels and small nerve bundles (HE 25×). (B) Within the tumor, some larger vessels presented a pr (...truncated)