Acinic cell carcinoma of the salivary glands: A literature review

Abstract

Acinic cell carcinoma (ACC) is a low-grade malignant salivary neoplasm that constitutes approximately 17% of primary salivary gland malignancies. In the head and neck region, the parotid gland is the predominant site of origin and women are usually more frequently diagnosed than men. Previous radiation exposure and familial predisposition are some of the risk factors for ACC. A slowly enlarging mass lesion in the tail of the parotid gland is the most frequent presentation. The diagnosis is usually confirmed with a fine needle aspiration biopsy, and surgical excision is the main treatment of this malignant neoplasm. Other treatment modalities such as radiotherapy may be indicated in some cases. ACC has a significant tendency to recur, to produce metastases (cervical lymph nodes and lungs), and may have an aggressive evolution. Therefore, long-term follow-up is mandatory after treatment.

Current Thinking on Malignant Salivary Gland Neoplasms

“…It accounts for approximately 5% to 17% of all salivary gland tumors and 10% to 17% of all malignant salivary gland tumors [28,[36][37][38]. The parotid gland is composed almost exclusively of serous type acini, and it is the most common site of AcCC (80% to 90% of cases); other reported sites are the palate (up to 15%), submandibular gland (4%), and sublingual gland (1%).…”

Synchronous bilateral acinic cell carcinoma of the parotid: When a tumor reveals another one

“…Likewise, there is no specific MRI signal distinguishing it from a benign tumor on conventional sequences [4]. On the other hand, as in the present case, dynamic perfusion sequences associated to diffusion-weighted sequences are able to suggest malignancy [8].…”

“…Two cases of a familial form were described, with a cytogenetic hypothesis based on findings of chromosomal mutations (in regions 4p, 5q, 6p, 17p [3,4] or 6q, Y-chromosome deletion [5]) probably involving tumor suppression genes. This malignant tumor is usually low-grade and slow-growth, and was long considered benign [6]; it is usually revealed by a parotid swelling, which may be painful or sensitive (in 10 to 50% of cases [2,4]), or associated with facial palsy (in 3 to 7% of cases [4,7]). There are more aggressive dedifferentiated forms [6] and prognosis is dependent on histologic type, which in turn correlates with risk of metastasis [7].…”

“…Diagnosis is based on anatomopathologic examination of the parotidectomy specimen, as acinic cell carcinoma is cytologically similar to benign forms, causing frequent false negative on fine-needle aspiration, which seemingly finds a normal parotid or a benign tumor [4]. Likewise, there is no specific MRI signal distinguishing it from a benign tumor on conventional sequences [4].…”

Acinic Cell Carcinoma of Nasal Cavity: A Rare Site for Salivary Gland Tumour

“…(9) Contradictory to the previous concept that IHC has limited role in the diagnosis of acinic cell carcinoma. (6) studies by Chenevert et al (5) has showed that DOG1 staining can be utilized to support the diagnosis of acinic cell carcinoma. In a study of 14 cases of salivary gland acinic cell carcinoma by Ihab Shafek Atta et al, all ACCs (100%) revealed positivity with DOG1 staining and the authors concluded that DOG1 has a higher efficacy in the diagnosis of ACC than α-amylase.…”