Epithelial-myoepithelial carcinoma of the parotid gland originating from pleomorphic adenoma

Abstract Introduction/Objective Myoepithelial carcinoma is identified by nearly exclusive myoepithelial differentiation and evidence of malignancy. It may arise de novo or in preexisting benign tumors including pleomorphic adenoma and benign myoepithelioma. It occurs most commonly in the parotid gland followed by submandibular glands, minor salivary glands, and occasionally in the sublingual gland. Nasopharyngeal origin has been rarely reported. Methods/Case Report An afebrile 19-year-old female presented to the emergency department with persistent facial pressure, otalgia (right side greater than left side), rhinorrhea, and several episodes of epistaxis. One month before, she has been treated with Amoxicillin for three days with no relief, where Augmentin started for her for five days. About four days prior presentation, she was placed on Prednisone and Cefdinir. Over the next several days, she began having throat pain with difficulty swallowing. Routine blood work revealed a leukocytosis of 14.2 with normal differentiation. CT of the neck showed a large soft tissue mass centered at the right nasopharynx. Flexible nasal endoscopy performed bilaterally to reveal the nasopharynx is entirely obstructed with a lobulated mass filling the nasopharynx. On the right side, it extends into the posterior nasal passage filling the sphenoethmoid recess and the posterior floor of the nasal passage. Outpatient biopsy from nasopharynx mass is also performed. Results (if a Case Study enter NA) Mass biopsy reveals a mucinous and chondromyxoid background with mixed epithelial and myoepithelial differentiation. The is squamous metaplasia of myoepithelial cells and prominent mitotic activity and apoptotic activity. Immunohistochemistry was positive for CK5/6, calponin, BCL2, SMA, BerEp4, Sox10, and a proliferative index up to 40%. Based on this information Myoepithelial Carcinoma ex-pleomorphic adenoma of the nasopharynx is the diagnosis. Conclusion Carcinoma ex pleomorphic adenoma is usually a high-grade malignancy. It occurs most commonly in the parotid gland, followed by submandibular glands, minor salivary glands, and occasionally in the sublingual gland. Our case is one of the few cases of myoepithelial carcinoma arising in nasopharyngeal pleomorphic adenoma.

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Ki-67 Index in Salivary Gland Neoplasms

International Journal of Phonosurgery & Laryngology ◽

10.5005/jp-journals-10023-1110 ◽

2016 ◽

Vol 6 (1) ◽

pp. 1-7

Author(s):

Suma Kaza ◽

T Jaya Mastan Rao ◽

Anupama Mikkilineni ◽

G Venkata Ratnam ◽

D Ranga Rao

Keyword(s):

Salivary Gland ◽

Pleomorphic Adenoma ◽

Mucoepidermoid Carcinoma ◽

Salivary Gland Neoplasms ◽

Carcinoma Ex Pleomorphic Adenoma ◽

Myoepithelial Carcinoma ◽

Cell Adenoma ◽

Ki 67 ◽

Adenoid Cystic ◽

Epithelial Myoepithelial Carcinoma

Abstract Assessment of proliferation is a means of predicting local recurrence and metastatic potential of malignancies. A mitotic count is not an ideal marker for proliferation in certain situations, such as salivary gland neoplasms. Ki-67 expression as a proliferation marker has been investigated in many human tumors. In the present study, Mitotic index (MI) and Ki-67 index were studied in pleomorphic adenoma, basal cell adenoma, mucoepidermoid carcinoma, adenoid cystic carcinoma epithelial myoepithelial carcinoma, carcinoma ex Pleomorphic adenoma and adenocarcinoma of salivary glands. The results were compared. The MI was similar in benign neoplasms, mucoepidermoid carcinoma and epithelial myoepithelial carcinoma, whereas it was high in carcinoma ex pleomorphic adenoma, adenocarcinoma and adenoid cystic carcinoma. The Ki-67 index was different in basal cell adenoma and pleomorphic adenoma. It was helpful in differentiating high grade and low grade mucoepidermoid carcinoma. It highlighted the malignant behavior of epithelial myoepithelial carcinoma. It was concluded that Ki-67 in benign neoplasms is 5% or less and in malignant ones more than 23% with a few exceptions. In mucoepidermoid carcinoma and epithelial myoepithelial carcinoma, Ki-67 index was found to be a better indicator for aggressiveness. These findings will be presented in this paper, with review of literature. How to cite this article Kaza S, Rao TJM, Mikkilineni A, Ratnam GV, Rao DR. Ki-67 Index in Salivary Gland Neoplasms. Int J Phonosurg Laryngol 2016;6(1):1-7.

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