Case Reports Submandibular Malignant Myoepithelioma Ollivier Laccourreye, MD, Laurent Laccourreye, MD, Luca Muscatello, MD, Jean-Pierre Charial, MD, Frangoise Carnot, MD, and Daniel Brasnu, MD (Editorial Comment: The authors clearly report an unusual salivary gland malignancy. The conse- quences of initial misdiagnosis are clearly shown.) In 1943, Sheldon1 was the first investigator to report malignant myoepithelioma of the major salivary gland. Only 15 cases of malig- nant myoepithelioma of the major salivary gland have been reported in the medical litera- ture.1-8 According to past reports, malignant myoepithelioma of the major salivary gland always arose within the parotid gland.le8 The present report documents the first case of submandibular malignant myoepithelioma. The differential diagnosis, treatment, and prog- nosis of this tumor are discussed together with a review of the literature. CASE REPORT A as-year-old man was referred at our clinic with a 4 X s-cm tumor located by the right submandibu- lar region. His medical history indicated tumor enucleation and submandibular resection for pleo- morphic adenoma performed at another institution 25 and 8 months earlier, respectively. Physical examination noted a right marginal mandibular nerve paresis. The remainder of the findings on head and neck examination were within normal limits. Computed tomography scans of the neck were also within normal limits. Treatment included resection of the tumor, adjacent muscles (mylohy- From the Department of Otorhinolaryngology-Head and Neck Surgery, the Department of Pathology, Univer- sity Paris V, LaQnnec Hospital, Paris; and the Depart- ment of Otorhinolaryngology-Head and Neck Surgery, University of Angers, France. Address reprint requests to Ollivier Laccourreye, MD, Department of Otorhinolaryngology-Head and Neck Sur- gery, Laennec Hospital, Assit%cepublique des Hopitaux de Paris, Universitv Paris V. 42 rue de Sevres. 75007. Paris, France. _ Copyright 0 1997 by W.B. Saunders Company 0196-0709/97/l 805-0007$500/O oid and platysma), and cutaneous scar. Pathological analysis suggested recurrent benign pleomorphic adenoma. Local recurrence invading the mandible associated with ipsilateral jugulocarotid nodal me- tastasis occured 2 months later. Surgical resection and ipsilateral modified neck dissection was then performed. Pathological analysis evoked again a recurrent pleomorphic adenoma. Skin (scalp) and brain metastasis occurred 1 month later. Skin bi- opsy showed scattered tumoral nodules with a histological pattern identical to the previous re- ports. However, higher cellularity and numerous mitoses were observed. Death occured 1 month latter. Permission for autopsy was denied by rela- tives. Following the fatal outcome, this case was re- viewed by a panel of pathologists from the Euro- pean Organization of Research on Treatment of Cancer (EORTC) specializing in salivary gland tu- mors (Figs l-3). The initial submandibular tumor was a well-delimited nodule. Histological review of the initial enucleated tumor and recurrent tumors noted a pleomorphic proliferation of spindle, plasm- cytoid, and sometimes clear cells with solid or loose pattern in a myxoid matrix (Fig 1). Nuclear pleomorphism and mitoses were scarce, except in the skin metastasis where more than 10 mitoses by 10 high-power fields were noted. No ductal struc- tures were found except in the initial submandibu- lar tumor in one area. Focal chondroid stroma was present in one nodal metastasis (Fig 2). Ultrastruc- tural analysis with electron microscopy was not performed. Immunostaining results showed faint and focal positivity for cytokeratin (KLl), strong and diffuse reactivity for S-100 protein (Fig 3), and vimentin. Results of immunohistochemical stain- ing for smooth-muscle-specific actin were nega- tive. On the basis of the clinical data together with the histological and immunohistochemical analy- sis, the review panelists considered the initial tumor as well as the recurrences to be misdiagnosed malignant myoepithelioma. DISCUSSION Myoepithelial cells are ectodermally de- rived contractile cellseg Such cells share the American Journal of Otolaryngology, Vol 18, No 5 (September-October), 1997: pp 331-334 331