Exophthalmos secondary to zygomatic adenocarcinoma in a dog

An 8-year-old Labrador Retriever developed unilateral exophthalmos over a 1-year period. Contrast radiography, surgical exploration, and histologic examination revealed the cause to be an adenocarcinoma arising from the zygomatic salivary gland or duct.

Solitary intraductal papilloma of the minor salivary glands

A case of solitary intraductal papilloma of a minor salivary gland is presented. The lesion was diagnosed clinically as a mucocele and has not recurred in 6 months of observation. This case is compared, on the basis of clinical data and histomorphologic findings, to three other known cases. Discussion is made of the role this lesion might play in the etiology of ductal obstruction, and the histologic findings of the intraductal papilloma of minor salivary glands and the solitary intraductal papilloma of the breast are compared.

[An interesting case]

A rare observation on a 57-year-old female patient serves to emphasize that striking findings may also occur in the orofacial region. In the present case, the patient was afflicted with a tubular cystadenoma of the oral mucosa, extending from 22 to 24. In this connection, the authors briefly deal with the epidemiology, clinic and morphology of these tumours.

Synchronous malignant mucoepidermoid tumor of the parotid gland and Warthin's tumor in adjacent lymph node

A case of a malignant mucoepidermoid tumor (poorly differentiated) occurring simultaneously with a homolateral Warthin's tumor is presented. The simultaneous occurrence of two salivary gland tumors of different types is extremely rare. Only five cases have been reported in the literature. The occurrence of a malignant mucoepidermoid tumor and a Warthin's tumor in the same patient has not been previously reported.

Myoepithelioma of minor salivary gland origin. Light and electron microscopical study

A gingival tumor that invaded the anterior maxilla was removed from a 14-year-old boy and studied by light and electron microscopy. The tumor was composed exclusively of myoepithelial cells and appeared to be malignant. By light microscopy, the tumor appeared to be a poorly differentiated epithelial neoplasm of undetermined origin; however, electron microscopical examination showed myoepithelial differentiation, indicative of a salivary gland origin. To our knowledge, the present case represents the only confirmed myoepithelioma that shows features indicative of malignant potential. Myoepitheliomas may be related to mixed tumors of salivary glands.

Metastatic malignancy in the submandibular gland

Metastatic disease in the major salivary glands has been observed and reported in the literature. Often the site of origin of the primary tumor is the skin or mucosal lining of the head and neck structures, and the primary tumors most commonly are melanomas or squamous-cell carcinomas. The most frequently involved salivary gland is the parotid. The submandibular and sublingual glands are rarely involved by mestastatic disease. Secondary lesions arising from distant primary tumors may occasionally involve the parotid gland, but they are extremely rare in the other major salivary glands. The second reported case of metastatic carcinoma in the submandibular gland is presented here. Our case and the previously reported case are similar in that both primary tumors originated in the breast. The clinical and morphologic features are reviewed.

Malignancy and the benign lymphoepithelial lesion

The benign lymphoepithelial lesion of salivary glands is now considered the histological hallmark of a variety of clinical and pathological disorders affecting salivary tissues. Malignancy arising in the lesion is uncommon, but may take origin in either the epithelial or lymphoreticular components. Lymphomas and pseudolymphomas associated with salivary gland lymphoepithelial lesions have been predominately extra-salivary and strongly correlated with Sjögren's syndrome. Epithelial malignancy has not been associated with autoimmunity and with few exceptions has been of the anaplastic type. This report presents two patients with intra-salivary lymphomas arising in a benign lymphoepithelial lesion of salivary glands and a patient with anaplastic carcinoma arising in the epithelial islands of the lesion. The fourth patient manifested pseudolymphomatous lymphoreticular hyperplasia in lung and submandibular gland and illustrates the possible multiple organ involvement that may occur in patients with benign lymphoepithelial lesion, even without clinical evidence of concommitant autoimmune disorders.

Benign lymphoepithelial lesions of the salivary glands

The benign lymphoepithelial lesion of the salivary glands has been labeled with multiple, confusing terms. We recommend the abandonment of the vague term of Mikulicz disease. The histopathologic findings of lymphoid infiltration, intraductal proliferation, epimyoepithelial islands, and acinar atrophy are presented. The relationship between this lesion and autoimmune diseases, including Sjögren syndrome, is noted. Difficulty of histopathologic differentiation between this lesion and malignant lymphoma can occur. The association of the benign lymphoepithelial lesion with the simultaneous presence or future development of lymphoma is discussed.

Carcinoma and cirrhosis of the liver in A X C male rats with one kidney ingesting 0.025% N-2-fluorenyldiacetamide

The role of the kidneys in hepatic carcinogenesis was studies in inbred A X C strain male rats ingesting 0.025% N-2-fluorenyldiacetamide. The experimental groups consisted of male rats with both kidney intact and male rats that had the left kidney removed. The incidence of hepatic carcinomas and the number of rats with large carcinomas, multiple carcinomas, poorly differentiated and undifferentiated carcinomas, and metastases was greater in rats with a left nephrectomy. The incidence of cirrhosis was the same in animals in both groups; however, cirrhosis was more severe in degree in the rats with the left kidney removed. Some animals in the latter group also developed carcinosarcomas of the salivary glands. The animals with one kidney apparently were not able to excrete the active metabolites of N-2-fluorenyldiacetamide as readily as the animals with both kidneys intact. The metabolites were then returned to the liver and salivary gland.

Histological changes in the submandibular glands of rats after intraductal injection of chemical carcinogens

Carcinogens injected into the excretory canal of submandibular gland of Donryu rats revealed the following histologic changes in salivary glands. 20-Methylcholanthrene induced squamous cell metaplasia, fibrosis in the early stages, and "benign lymphoepithelial lesion"-like pattern after 3 months. Dense hyalinization occurred after 4-5 months with so-called "mixed tumor"-like pattern. In the later stages epidermoid carcinoma and fibrosarcoma were observed. 9, 10-Dimethylbenzanthracene caused degenerative change, metaplasia, fibrosis and cell infiltration, and later carcinoma and sarcoma appeared at a high rate. 4-Nitroquinoline-N-oxide led to dense hyalinization and so-called "mixed tumor"-like pattern was observed in many specimens. N-nitroso-N-methyl urethane and N-methyl-N-nitroso-N'-nitroguanidine revealed metaplastic changes, fibrosis and lymphoid infiltration. Scarlet red induced remarkable infiltration and aggregation of lymphoid cells, showing benign "lymphoepithelial lesion"-like pattern.

Leukocyte mediated cytotoxicity of chemically induced rat salivary gland neoplasms

Chemically induced tumors of the rat submaxillary glands were tested for the presence of tumor antigens by in vitro leukocyte mediated cytotoxicity assays. Since it has been reported that the saliva of humans with oral cancer contains markedly elevated levels of secretory antibody, the rats' saliva specimens were also tested for blocking and/or potentiating "antibody" activity. The results indicate that saliva from tumor-bearing animals potentiated tumor cell killing if either the tumor cells or leukocytes were pretreated. The effect was much more marked when tumor cells were pretreated. Furthermore, the addition of saliva to tumor cells imparted an immunologic cross reactivity which was not present with untreated tumor cells. Control saliva occasionally produced a similar effect, but not as consistently or with the potency of saliva from tumor-bearing animals. Heat inactivation did not abrogate this potentiation. It is inferred that this may indicate a new system of immunologic surveillance, i.e. arming or potentiation of leukocytes by soluble tumor antigens in glandular secretions.