Signet ring carcinoma parotid gland: A case report

Department of Pathology, Maulana Azad Medical College and Lok Nayak Hospital, Bahadur Shah Zafar Marg, New Delhi, India.
Head & Neck (Impact Factor: 2.64). 11/2011; 33(11):1656-9. DOI: 10.1002/hed.21435
Source: PubMed


Signet ring adenocarcinoma is a recently characterized entity occurring in the minor salivary glands. All reported cases have occurred in minor salivary gland. Pure signet ring adenocarcinoma of a major salivary gland has not been reported in the literature.
A 38-year-old woman presented with a mass in the parotid region. Microscopy showed signet ring cells positive for mucicarmine. Immunohistochemistry showed cytokeratin and focal smooth muscle actin (SMA) positivity; an exhaustive search for primary elsewhere did not reveal any suspicious focus.
A diagnosis of low-grade signet ring adenocarcinoma of the parotid gland was made. On 6-month follow-up the patient was alive and well.
The present case highlights a rare occurrence of this tumor in the parotid gland, which until now was labeled as a tumor exclusive to minor salivary glands. Thus this entity should be kept as a differential while investigating mucinous tumors of parotid.

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