While sinonasal intestinal type adenocarcinoma (ITAC) is defined by an intestinal phenotype, non-intestinal type adenocarcinoma (non-ITAC) is traditionally viewed as a diagnosis of exclusion, despite previous implication of a seromucinous phenotype and similarity to sinonasal seromucinous hamartomas (SSH). We performed a comparison of clinicopathologic and immunophenotypic features of ITAC, non-ITAC and SSH using traditional discriminatory markers and new markers of seromucinous differentiation. Twenty-three non-ITAC, 17 ITAC, and 5 SSH were retrieved (1987-2014). As expected, ITAC occurred predominantly in the nasal cavity in elderly patients (mean age 65 years) with a striking male predilection (15:2). Regardless of grade/subtype, all ITAC were invariably CK20 and CDX2 positive, and many (11/15) showed some CK7 positivity. Non-ITAC occurred in younger individuals (mean age 51 years) with a slight female predilection (male to female ratio: 10:13) and showed diverse morphologic patterns and grades, some with morphologic similarity to SSH. SSH occurred in younger individuals (mean age 33 years). Non-ITAC and SSH were invariably CK7 positive and CK20 negative, however, 4/22 non-ITAC and 2/5 SSH showed squamoid morular metaplasia that aberrantly expressed CDX2 and co-expressed nuclear β-catenin. Markers of seromucinous differentiation (S100, DOG1, and SOX10) were essentially absent in ITAC, but present to varying degrees in the majority of non-ITAC and all SSH. Thus, the term 'seromucinous adenocarcinoma' is the more appropriate designation for non-ITAC. Squamoid morules in non-ITAC and SSH may be an immunophenotypic pitfall given the aberrant CDX2 expression.

Kimura disease is a rare, benign, chronic inflammatory swelling of the subcutaneous tissue, lymph nodes, and glandular tissue. Characteristic features of the disease include, but not limited to, painless subcutaneous head and neck swelling, blood and tissue eosinophilia, and markedly elevated immunoglobulin E (IgE) levels. Herein, we report a rare case of Kimura disease manifesting as synchronous bilateral parotid swelling of 12 years duration in a 33-year-old Middle-Eastern man. To our knowledge only few cases have been reported in the literature involving bilateral parotid glands, and this is the first case to be reported in the Middle East.

Sclerosing paragangliomas are rare tumors, and only 1 case involving a primary thyroid mass has been reported in the literature. Although the sclerosing variant has features suggestive of malignancy, the true incidence of malignancy is unknown, given the rarity of its presentation. However, given the overall benign nature of paragangliomas, the sclerosing variant is also likely benign, despite its malignant features on ultrasound and histopathologic examination.

No abstract

Signet ring cell (mucin producing) adenocarcinoma is a rare low grade salivary gland malignancy. While currently designated as an adenocarcinoma, myoepithelial differentiation has been implied in previously reported cases. We herein perform a survey of our cases of signet ring cell adenocarcinoma and review the literature in order to refine categorization of this rare tumor. Five cases were retrieved. One was reclassified as a mammary analogue secretory carcinoma, leaving four that fulfilled the criteria for signet ring cell adenocarcinoma: the presence of prominent signet ring or vacuolated cells arranged in islands, interconnecting strands, cords or sheets in a myxoid or hyaline stroma, or pools of mucin. An extensive panel of histochemical and immunohistochemical stains and fluorescence in situ hybridization (FISH) (modeled after common phenotypes and molecular alterations seen in signet ring and myoepithelial tumors at other sites) was performed. The male-to-female ratio was 3:1. The mean age was 56 years (range 18-81). Sites involved included buccal mucosa (2), soft palate (1) and deep parotid (1). Perineural and angiolymphatic invasion were present in three and two cases respectively. One patient was lost to follow up and the remainder were alive and without disease at time of last follow up (mean 38 months). All cases showed mucicarmine positive vacuolated/signet ring cells embedded in a myxoid stroma. Three cases showed at least focal p63 staining and two cases showed positivity for calponin. Membranous E-cadherin was retained in all cases. FISH was negative for ETV6, EWSR1, and ALK1 rearrangements in all four cases. Based on the current series and the previously reported cases, it is evident that signet ring adenocarcinomas have a dual secretory and myoepithelial phenotype and thus as a whole more appropriately designated as 'secretory myoepithelial carcinoma.' They behave in a fairly indolent fashion and do not share the major molecular alterations seen in other signet ring and myoepithelial tumor types.

Castleman disease is an extremely rare benign lymphoproliferative disorder of unknown etiology. It affects the lymphatic chain in anybody region, although the commonest site is the mediastinum. The head and neck region is the second most common site; however, the salivary glands are rarely affected. We report a case of a 29-year-old Asian lady who presented with a 2-year history of an enlarging left parotid mass. Histopathology of the excisional biopsy confirmed the diagnosis of Castleman disease.

No abstract

Ectopic salivary tissue is commonly found in intraparotid and periparotid lymph nodes. Warthin tumor is the most common tumor arising in ectopic salivary gland tissue and in intraparotid lymph nodes. Although rare, neoplastic transformation of the ectopic salivary tissues is conceivable and other types of salivary gland neoplasms arising in intraparotid lymph nodes have been reported. Herein we report a rare case of a 32-year-old Kuwaiti male who presented with a mass in the right parotid gland. A preoperative fine needle aspiration suggested Warthin tumor. The patient underwent a superficial parotidectomy. The specimen showed a mass within the parotid parenchyma abutting the deep margin. Hematoxylin and Eosin stained sections of the lesion showed solid islands and cysts composed of epidermoid cells, mucus cells, and intermixed smaller “intermediate” cells within an intraparotid lymph node. The tumor was seen infiltrating the parotid parenchyma at the deep margin. Metastasis from distant sites was ruled out clinically, and the diagnosis rendered was MEC, low-grade, arising from ectopic salivary tissue in an intraparotid lymph node. Such cases are extremely rare and the presence of malignancies within lymph nodes may pose a diagnostic pitfall, which can affect patient management.