Acinic cell carcinoma of the parapharyngeal space: case report

Acinic cell carcinoma of the head and neck: radiologic-pathologic correlation

OBJECTIVE

To describe and correlate the imaging and pathologic findings of acinic cell carcinoma (ACC) in the head and neck.

METHODS

We reviewed the radiologic findings of 12 patients with pathologically proven ACC in the head and neck. They were 6 males and 6 females (ages: 5-75 years, mean 36 years) who undergoing computed tomography (CT, n=9) and CT with magnetic resonance (MR) imaging (n=3).

RESULTS

The lesions in the superficial lobe of the parotid gland were solid (n=7), cystic (n=1), and cystic mass with mural nodule (n=1) on CT. A parapharyngeal lesion was cystic mass with mural nodule, and a submandibular and a palate tumor were cystic lesions on CT. All solid masses in the parotid gland (n=7) included focal low-attenuating portions on CT, which were microcyst, hemorrhage, or necrosis on pathologic examination. We could not find intratumoral calcifications or metastatic lymphadenopathy on imaging and histologic studies in all 12 cases. Internal hemorrhage on the MR images was seen in a parapharyngeal and a parotid lesion.

CONCLUSION

Although ACC appears to have nonspecific imaging findings, familiarity with some imaging features can be helpful for differential diagnosis of head and neck tumors.

Acinic cell carcinoma with follicular pattern of the soft palate

Acinic cell carcinoma (ACC) is an uncommon low-grade malignancy of the salivary glands. Most cases occur in the major salivary gland, but a few cases affecting the minor salivary gland have also been described. Although various growth patterns have been reported in the literature, a few cases have been diagnosed as ACC with follicular pattern. We present a rare case of ACC with follicular pattern of the soft palate in a 60-year-old man. The occurrence of ACC in this area is extremely rare, and its striking thyroid-like appearance may cause confusion in the differential diagnosis.

?Parapharyngeal space? tumors: A cytopathological study of 24 cases on fine-needle aspiration

The parapharyngeal space (PPS) is a well-defined anatomic zone of loose connective tissue lying deep to the tonsil and lateral to the pharynx. Neoplasms arising within the PPS are rare. We retrospectively reviewed 24 PPS fine-needle aspirations (FNAs) performed at The Johns Hopkins Hospital over the past 16 years (1987-2002). Patients presented with neck pain, dysphagia, and/or intraoral swelling of varying duration. Radiographic imaging disclosed PPS masses, varying in size from 2.5 to 8 cm. The most common clinicoradiographic suspicion was a nerve sheath tumor. Six cases had FNA performed using a 23-gauge needle via a transoral approach in the outpatient suite whereas the remainder were aspirated via a 22-gauge Franseen needle under CT guidance. Six of 24 cases (25%) were nondiagnostic due to lack of adequate cellular material. Of the 18 cases considered diagnostic, there were nine (50%) pleomorphic adenomas (PAs); three (17%) squamous-cell carcinomas (SCC); and one each of oncocytoma, adenocarcinoma, not otherwise specified (NOS), adenoid cystic carcinoma, lipoma, neurofibroma, and non-Hodgkin lymphoma, together comprising the remaining 33%. Four of the six cases deemed nondiagnostic (consisting predominantly of blood) on subsequent tissue follow-up revealed paraganglioma (two cases), SCC (one case), and schwannoma (one case). PPS is an uncommon target of an FNA procedure. PPS masses represent a heterogeneous group of neoplasms of which PA appears most common, representing 50% of our diagnostic cases. The rate of nondiagnostic FNA samples is moderately high due to excessive bleeding encountered in this location and other technical problems relating to adequately targeting the lesion in close vicinity of major neck vessels.