The acinic cell carcinoma (ACC) is very rare in the nasal cavity. A 57-year-old woman suffered from nasal obstruction, postnasal dripping, and hyposmia for 2 months.
Rhinoscopic examination revealed a huge polypoid mass in the right inferior and anterior nasal fossa of the nasal cavity and the mass was resected.
The tumor showed the classic acinar and trabecular features of ACC on light microscopic examination. The finely granular cytoplasmic granules stained with periodic acid-schiff (PAS) and diastase digested-PAS, but not with alcian blue at pH 2.5 and mucicarmine. On ultrastructural examination, tumor cells contained numerous secretory granules diagnostic of ACC.
We experienced a case of well-differentiated acinic cell carcinoma of the parotid gland in a 65 year-old woman, which was correctly diagnosed preoperatively by fine needle aspiration(FNA) cytology. FNA cytology smears showed clusters or sheets of monomorphic acinic cells having reticulated or finely vacuolated basophilic or acidophilic cytoplasm. The cellular population was homogeneous or slightly polymorphic, having centrally located, round nuclei with finely reticular chromatin and incon- spicuous nucleoli. Herein we report this case with its histologic features and review of literatures.
Acinic cell carcinoma is a slow-growing solid neoplasm of salivary gland. Although their cytological and histological finding is bland-looking, their biological behavior is unpredictable. We experienced two cases of acinic cell carcinoma of the salivary gland diagnosed by fine needle aspiration biopsy and confirmed by tissue examination. They showed different clinical courses. We compared their cytologic and histologic findings. The first case was a right preauricular mass in a 58 year-old female of 3 years duration. The cytologic smear revealed sheets or small clusters of monotonous cells mimicking normal serous acinar cells with little cellular pleomorphism. She underwent superficial parotid lobectomy. The tumor was a well demarcated 1.5cm sized nodular mass without infiltration into surrounding parenchyme. The second case was a left submandibular mass in a 23 year-old male of 4 years duration. The smear showed more severe pleomorphism of the tumor cells than those of previous case. Excisional biopsy was done. The excised tumor was 5.5*3.5*3cm sized multilobulated solid mass with invasion into surrounding parenchyme. The tumor recurred after 20months, thus total excision of the mass and modified radical neck dissection was carried out. From the above findings, cytologic atypism, infiltrative growth pattern and type of initial therapy may be correlated with biologic behavior.
Acinic cell carcinoma(ACC) is the third common malignancy in major salivary gland. Fine needle aspiration cytology is a useful tool for the diagnosis of salivary gland lesions.
However, some low grade malignancies, such as ACC and mucoepidermoid carcinoma show relatively high false negative rate, mainly due to deceptively benign cytomorphologic appearance. We experienced a papillary-cystic variant of ACC, having different cytopathologic features compared with those of classic ACC. Our case showed monolayered sheets and papillary clusters without any acinic structures or naked nuclei of the tumor cells. Foamy proteinaceous material was seen in the background. The tumor cells had a large amount of granular cytoplasm and eccentric nuclei. Many vacuolated or clear cells were also noted.