Sebaceous lymphadenocarcinoma of salivary glands

Primary sebaceous neoplasms of the salivary glands are extremely rare occurrences; furthermore, sebaceous lymphadenocarcinoma has only been reported in three patients. We report a case of sebaceous lymphadenocarcinoma arising in a lymphadenoma of the parotid gland. The patient was a 55-year-old man who presented with a parotid mass of 3 years' duration. Histologically, the lesion consisted of a sebaceous lymphadenoma with transition to a sebaceous carcinoma. The cytologic touch-preparation at the time of frozen section showed clusters of benign sebaceous cells in a rich lymphocytic background together with tridimensional clusters of malignant epithelial cells, strongly raising the suspicion of a malignant neoplasm arising in a benign sebaceous lesion. Malignant transformation of the sebaceous lymphadenoma, although rare, should be considered in enlarging, locally invasive parotid lesions, considering that clinical behavior and prognosis will be determined by the nature of the malignant component.

E-cadherin immunohistochemical analysis of histiocytoid carcinoma of the breast

Histiocytoid carcinoma is a rare type of invasive breast carcinoma. It has been considered to be a variant of lobular carcinoma, a variant of apocrine ductal carcinoma, and an apocrine variant of lobular carcinoma and to resemble lipid-rich carcinoma. In attempts to elucidate its histogenesis, investigators have used mucin and oil red O histochemical analysis and GCDFP-15 immunostaining. E-cadherin is a relatively recent addition to the armamentarium of immunohistochemical markers used for cell differentiation and is a member of a family of transmembrane glycoproteins that has been shown to have a strong correlation with the histologic phenotypes of breast carcinoma. Most ductal carcinomas show diffuse membrane expression of E-cadherin, and lobular carcinomas are characterized by complete lack of membrane staining of E-cadherin. The object of this study was to use E-cadherin immunohistochemical analysis to help clarify the histogenesis of histiocytoid carcinoma. Fourteen cases containing the diagnosis of histiocytoid carcinoma of the breast were identified at M. D. Anderson Cancer Center (Houston, TX) from 1988 to 2001. All cases were rereviewed, histologic features were evaluated, and immunohistochemical staining with E-cadherin and GCDFP-15 was performed. Clinical information was extracted from the patients' medical records. Eleven cases met published histologic criteria for histiocytoid carcinoma. The remaining three cases were apocrine carcinoma. The pattern of tumor infiltration was solid, without secondary lumen formation in all cases of histiocytoid carcinoma. Lobular carcinoma in situ was identified in eight cases, but was absent in three. There was no E-cadherin immunohistochemical staining in eight of the 11 cases of histiocytoid carcinoma (72.7%). GCDFP-15 was immunoreactive in all 10 cases of histiocytoid carcinoma where it was performed. Follow-up data was available for nine of the 11 cases of histiocytoid carcinoma: six patients were alive with disease at 1.5 to 48 months, one patient had died of disease at 60 months, and two patients had no evidence of disease at 32 and 45 months. We conclude that histiocytoid carcinoma has an immunophenotypical profile consistent with both ductal and lobular differentiation. Moreover, the lack of consistent morphologic features, a specific clinical profile, and a distinct immunohistochemical pattern lead us to hypothesize that histiocytoid carcinoma is not a special type of breast cancer.

Hybrid carcinomas of salivary glands. Report of 4 cases and review of the literature

OBJECTIVE

To report 4 cases of hybrid carcinoma and to review the literature on these rare neoplasms of the salivary gland.

METHODS

Hematoxylin-eosin-stained, formalin-fixed, paraffin-embedded tissue sections from 3 parotid tumors and 1 palate tumor were examined.

RESULTS

The cases were classified as adenoid cystic and mucoepidermoid carcinoma, adenoid cystic and epithelial-myoepithelial carcinoma, epithelial-myoepithelial and salivary duct carcinoma, and adenoid cystic and salivary duct carcinoma. All patients were men, 28 to 71 years old; 3 patients presented with parotid mass, and 1 patient presented with palatal mass. One patient presented with facial nerve paralysis and pain. The soft palatal tumor was a slowly growing mass with maxillary sinus involvement at the time of the diagnosis. All patients were treated with surgery and radiotherapy.

CONCLUSIONS

Correct identification of 2 or more neoplastic entities will help assess the aggressiveness and metastatic potential of the tumor and influence the clinical course and treatment.