J Oral Maxillofac Surg 60:1494-1496, 2002 Subacute Necrotizing Sialadenitis in the Buccal Mucosa Wagner Henriques Castro, DDS, MS,* Se ´rgio Neves Drummond, DDS,† and Ricardo Santiago Gomez, DDS, PhD‡ Subacute necrotizing sialadenitis (SANS) is a recently described inflammatory disease of unknown etiology that affects oral minor salivary glands. This lesion generally presents as a localized erythematous palatal papule or nodule with a sudden onset, and it seems to be a self-limiting condition. 1-3 The microscopic evalu- ation of SANS shows a nonulcerated oral mucosa overlying minor salivary glands diffusely infiltrated by acute and chronic inflammatory cells. Atrophy and necrosis of duct and acinar cells are observed. To date, only 3 reports are found in the literature about this condition, and all of the cases reported were localized in the hard and soft palate. The purpose of the present article was to report a case of SANS in the buccal mucosa and to improve the characterization of this new condition. In addition, because the possibil- ity of a viral etiology has been raised concerning the pathogenesis of SANS, 1 immunolocalization of early and late cytomegalovirus (CMV) antigens was also investigated. Report of a Case A 30-year-old woman was referred with a painful submu- cosal nodule on the left buccal mucosa of 1 month’s dura- tion (Fig 1). The medical history was not contributory. With the differential diagnosis of benign mesenchymal or glandu- lar neoplasm, lymphoid hyperplasia, epidermoid cyst, or mucocele, an excisional biopsy was performed. The his- topathologic examination showed a nonulcerated oral mu- cosa with a submucosal diffuse infiltration of minor salivary glands by a mixed inflammatory infiltrate of lymphocytes, neutrophils, histiocytes, and some eosinophils (Fig 2). The ducts showed atrophy, mild dilatation, or necrosis, and the acinar cells showed early necrosis with involvement by polymorphonuclear neutrophils or mononuclear inflamma- tory cells (Figs 3, 4). Immunohistochemical investigation was performed for identification of CMV early and late antigens. Briefly, tissue blocks were cut into sections 3 m thick and subjected to the biotin-streptavidin labeling. For microwave antigen retrieval, the slides were subjected to microwave (700 W)/citrate buffer (pH 6.0, 10 mmol/L) pretreatment for 10 minutes (3  5 minutes) and then left to cool for 20 minutes. The primary antibodies used were anti-CMV early antigen (Clone QB1/42, 1:25 dilu- tion; Novocastra, Newcastle upon Tyne, England), and anti-CMV late antigen (Clone QB1/06, 1:25 dilution; Novocastra). Peroxidase was visualized with 3'-diamino- benzidine and counterstained with Mayer’s hematoxylin. The results did not show positive immunoreaction for ei- ther antigen. Discussion SANS was recently recognized; although only 3 reports that describe it appear in the English-language literature, it may not be a rare lesion. As was pointed out by van der Wal et al, 2 the self-limiting nature of the disease may lead to spontaneous healing of the lesion before patient evaluation occurs. All of the cases reported involved the location of the palate, and the present case was the first reported to affect the buccal mucosa. Fowler and Brannon 3 showed that patient age ranged from 15 to 45 years, with most cases occurring in the second and third decades. Men were more often affected; a predi- lection for whites was also noted. The duration of the lesions ranged from 1 day to 4 weeks, but in one case it was reportedly present for 6 years before diagnosis. Although the etiology of SANS has not been estab- lished, some clinical and microscopic features appear to favor a traumatic, an infectious, or an allergic eti- ology. Because none of the cases reported presented with an ulcerated oral mucosa, a traumatic factor Received from the Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. *Lecturer. †Resident. ‡Lecturer and Research Fellow of Conselho Nacional de Desen- volvimento Cientı ´fico e Tecnolo ´gico (CNPq). Address correspondence and reprint requests to Dr Gomez: Departmento de Patologia e Cirurgia, Faculdade de Odonto- logia, Universidade Federal de Minas Gerais, Av Antonio Carlos, 6627, Belo Horizonte MG, Brasil; e-mail: rsgomez@mail.odonto. ufmg.br © 2002 American Association of Oral and Maxillofacial Surgeons 0278-2391/02/6012-0018$35.00/0 doi:10.1053/joms.2002.36134 1494