BRIEF REPORTS Spontaneous Infarction of Pleomorphic Adenoma: Report of a Case Simulating Malignancy on Fine-Needle Cytology Sample Franco Fulciniti, M.D., Ph.D., 1 * Nunzia Simona Losito, M.D., 1 Gerardo Botti, M.D., 1 Marco Manola, M.D., 2 and Franco Ionna, M.D. 2 Ischemic or hemorrhagic infarction has been described as an uncommon but possible complication of fine-needle cytology sampling in numerous organs, more frequently the thyroid, the salivary glands, the breast, the lymph node, and the kidney. In these situations, infarction appears to be directly related to the vascular disturbances caused by needle sampling, though fine this latter might be. One case of a spontaneous infarction of a parotid pleomorphic adenoma in a 46-year-old lady is here described in which the cytopathologic findings, which were related to ischemic infarction, preceded fine-needle cytology sampling and mimicked malignancy. The cytopathologic picture showed a quizzical mixture of ne- crosis and inflammation coupled to hyperplastic changes of the acinar cells, oncocytic metaplasia, and atypical squamous meta- plasia of extreme degree simulating high-grade epidermoid- or mucoepidermoid carcinoma. Due to the cytologically suggestive changes, a nerve-sparing radical parotidectomy was performed. The differential diagnostic problems encountered in this case are discussed together to the possible medical–legal implications originating from such striking atypias as to closely simulate malignancy. Diagn. Cytopathol. 2010;38:430–434. ' 2009 Wiley-Liss, Inc. Key Words: salivary gland pathology; spontaneous infarction of pleomorphic adenoma; ischemic changes following fine- needle sampling; head and neck pathology Vascular disturbances following Fine-needle cytology (FNC) sampling, with or without aspiration, have been described in numerous organs mainly in the thyroid, 1–6 where their relative frequency deserved an histo- and cytopathologic codification, 2,3 the salivary glands, 7–12 the breast, 13–16 lymph nodes, 17,18 and the kidney. 19 Due to the widespread diffusion of FNC of the thyroid and to the rich vascularity of this gland, vascular disturbances fol- lowing FNC have first been described and elegantly codi- fied by LiVolsi and Merino 4 and by Kini in this organ. 5 Briefly, partial or total infarction of thyroid neoplasms following FNC may impede or endanger the histopatho- logical diagnosis in surgical samples because of their fol- lowing massive fibrosis, coagulative necrosis, or to the re- sidual presence of only a small rim of viable tumor tissue at the periphery of a malignant neoplasm. This small rim of tissue may be more easily overlooked by the histopa- thologist, especially if he is unaware of the cytopathologic diagnosis. 1–3,5 Moreover, even when a true infarct is lack- ing, myofibroblastic proliferation may ensue FNC as a post-traumatic response. These lesions are very cellular and, although entirely benign, may cause differential diag- nostic problems with other lesions containing spindle cells, like medullary or anaplastic carcinoma. 4 In the sali- vary glands, partial or total infarction may be caused by FNC sampling 7,9 or may be a spontaneous event and may concern benign tumors or malignancies. 8,11 In Warthin’s tumor, post-FNC infarction may lead to sudden increase in volume of the affected gland, coupled to pain or ten- derness. 7 In analogy to what described in the thyroid, in- farction of malignant tumors may impede the histopatho- logical diagnosis. 10 Moreover, infarcted organs may be prone to secondary infection. To our knowledge only two cases of spontaneous in- farction of pleomorphic adenoma have been previously 1 S.S.D. di Citopatologia, A.F. di Anatomia Patologica, Istituto Nazio- nale Tumori ‘‘Fondazione G. Pascale,’’ Naples, Italy 2 S.C. di Chirurgia Maxillo-Facciale-O.R.L, Istituto Nazionale Tumori ‘‘Fondazione G. Pascale,’’ Naples, Italy *Correspondence to: Franco Fulciniti, M.D., Ph.D., S.S.D. di Citopato- logia, A.F. di Anatomia Patologica, Istituto Nazionale Tumori ‘‘Fonda- zione G. Pascale,’’ Via M. Semmola, Naples 80131, Italy. E-mail: franco.fulciniti@gmail.com Received 4 August 2009; Accepted 28 August 2009 DOI 10.1002/dc.21229 Published online 5 November 2009 in Wiley InterScience (www. interscience.wiley.com). 430 Diagnostic Cytopathology, Vol 38, No 6 ' 2009 WILEY-LISS, INC.