Kazunari Sakurai

Primary hepatic carcinoid tumor

A case of primary carcinoid tumor arising in the liver of a 69 year old woman with no endocrine symptoms is reported. Histopathologically, the tumor was diagnosed initially as a hepatocellular carcinoma in the biopsy specimen, and was shown subsequently to be a carcinoid tumor, demonstrating diffuse positive staining with Grimelius method. Mucin stained with periodic acid‐Schiff (PAS), alcian‐blue, and mucicar‐mine, and was shown partially in the glandular structures. Immunohistochemically, most of the tumor cells stained positively for chromogranin‐A, epithelial membrane antigen (EMA) and neuron specific enolase (NSE). Ultrastructural examination revealed electron‐dense core granules, measuring 40‐120 nm in diameter in some of the tumor cells. Intensive and careful searches pre‐ and post‐operatively revealed no other primary source of tumor other than the liver. The patient was reported well with no symptoms 31/2 years after the operation.

Increased expression of c‐erbB‐3 protein and proliferating cell nuclear antigen during development of verrucous carcinoma of the oral mucosa

The roles of c‐erbB‐3 gene and protein in the pathogenesis, progression, and outcome of oral carcinoma remain unknown. To determine whether c‐erbB‐3 expression could serve as an indicator of progression from premalignant to malignant transformation and of prognoses in patients with oral carcinoma, the authors examined the relation between the expression of c‐erbB‐3 protein and cell proliferation activity during the development of oral verrucous carcinoma (VC).

Testicular seminoma with human chorionic gonadotropin production

Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG‐positive seminoma) is regarded as more malignant than marker‐negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β‐hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β‐hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β‐hCG level correlated only to the metastatic status. Immunohistochemical expression of β‐hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.

Prognostic significance of cyclooxygenase-2 and DNA topoisomerase IIα expression in oral carcinoma

Despite recent advances in the diagnosis and treatment of oral carcinoma, outcomes remain disappointing. The identification of new prognostic factors is necessary to improve survival. To determine the prognostic significance of cyclooxygenase (COX)‐2 and DNA topoisomerase (DNA‐Topo) IIα expression in patients with oral carcinoma, we immunohistochemically examined these enzymes and studied their relation to overall 5‐year survival.

Increased expression of cyclooxygenase‐2 in human salivary gland tumors

We examined the immunohistochemical localization of cyclooxygenase (COX)‐2 in human salivary gland tumors. Thirty salivary gland adenomas (SGA), 40 salivary gland carcinomas (SGC) and 15 normal salivary glands (NSG) were studied. NSG showed restricted COX‐2 staining only in the epithelial cells of salivary ducts. In contrast, COX‐2 protein was detected in 27 cases of SGA (90%), except for three myoepitheliomas, and in all cases of SGC (100%) at various intensities and in various fashions. Thirteen SGA (43%) and 36 SGC (90%) cases showed strong COX‐2 staining predominantly in tumor cells containing ductal components, as did serous and mucous acinic components of acinic cell carcinomas, mucoepidermoid carcinomas and mucinous carcinomas. These findings may suggest that COX‐2 in salivary gland tumors is expressed in tumor cells derived from pluripotential ductal epithelium that can histologically develop into either serous or mucinous acinar cells.

CONTRIBUTION OF CELL PROLIFERATIVE ACTIVITY TO MALIGNANCY POTENTIAL IN TESTICULAR SEMINOMA

Testicular anaplastic seminoma, which has a high mitotic activtiy, is regarded aa more malignant than typical seminoma, although its prognosis is still unclear. To determine whether seminoma with relativety greater malignancy potential can be ldentified based on the cell proliferative activity, the mitotic rate (MR; mitotic count per high‐power field), mitotic Index (MI; mitotic count per 1000 cells), Ki‐67 labeling Index (K1–67 LI; the percentage of positive cells) and prolifereting cell nuclear antigen LI (PCNA LI; the percentage of positive cells) were histologically examined In 44 patients. The MI, Kl‐67 LI and PCNA LI In patients with metastatlc disease were signmeantly higher than those in patients without metastatic disease, and the MI In patients with fatal disease was signmcantly higher than those in patients cured of the disease. However, these distributions of the MI, K1–67 LI and PCNA LI values overiapped for both pairs of groups. There were no significant differences in the YR. These results suggest that the cell proliferatbe activity makes a small contribution to the malignancy potential in testicular seminoma, with the activity being not necessarily indicative of metastasis and prognosis.

Benign mesenchymoma of the cheekReport of a case and review of the literature

Benign mesenchymoma is a soft tissue neoplasm that contains 2 or more differentiated mesenchymal components in addition to fibrous tissue. A rare case of benign mesenchymoma of the cheek in a 6-year-old boy is presented. The literature pertaining to mesenchymoma in the head and neck region is reviewed and discussed.

Endovascular papillary angioendothelioma (Dabska tumor) in an elderly woman

A patient with endovascular papillary angioendothelioma with a low grade of malignancy showing papillary proliferation of endothellold cells Is presented. The patient, an 83‐year‐old woman, underwent resection of a tumor of the neck. At operation a 9×7 cm cystic tumor containing yellow transparent liquid with clots was found In the subcutaneous tissue. Histological studies showed endotheliold cells with spindle‐shaped nuclei proliferated in layers around the fibrovascular cores, which showed the characteristic appearance of papillary proliferation. These cells were Immunohlstochemlcally positive for CD31, CD34 and factor VIII‐related antigen. Based on these observations, the tumor was considered to be an endovascular papillary angioendothelioma (Dabska tumor). Dabska tumor Is a vascular tumor with a low grade of malignancy and usually occurs in infants and young children. About 13 cases of Dabska tumor have been reported. The occurrence of a Dabska tumor In an aged patient is considered to be rare.

Primary squamous cell carcinoma of accessory parotid gland duct epithelium: Report of a case

A rare case of primary squamous cell carcinoma surrounding Stensens duct in a 75-year-old man is presented. The tumor was a relatively well-defined, hard, subcutaneous mass, measuring 18 x 14 x 9 mm and situated in the right cheek. Microscopic examination of an excisional biopsy specimen revealed tumor cells showing squamous differentiation, a papillary growth pattern, and ductal structures with comedo necrosis. Immunohistochemical studies showed positive reactivity for KL-1 (cytokeratin, monoclonal), epithelial membrane antigen, and carcinoembryonic antigen in some tumor cells. The origin of the tumor was thought to be the accessory parotid gland duct epithelium.

Immunohistochemical analysis of the nm23 gene products in testicular seminoma.

The nm23 gem, has been ldenwied as a metastasis suppressor gene. To clam the role of nm23 as a metastasis sup pressor gene In testicular seminoma, the expression of the nm23‐Hl and ‐H2 proteins (human nucleoside‐dlphosphate kinase‐A and ‐B) was Immunohistochemically examined in 43 patients. Thirty‐six (84%) and 21 (49%) of the 43 primary tumors were posithre for the nm23‐H1 and ‐H2 proteins, respecthrely. There was no significant difference in either nmH1 or ‐H2 expression between the 24 primary non‐invashre tumors and the 19 primary invasive tumors, or between the 31 primary tumors without metastasis and the 12 primary tumors with metastasls. In all, and 5 of 6 meta‐static tumors, the expression of nm23H1 and ‐H2 proteins was obsenred, respectively, and the expression was not decreased in the metestetlc tumors, compared to the primary tumors. In conclusion, the lmmunohistochemlcal expression of both the nm23‐Hl and ‐H2 gene products is not associated with the metastatic status or the invasive status of testicular seminoma, and it Is unlikely to be a useful non‐metastatic Indicator for testicular seminoma. Further studies are needed to elucidate the biological role of nm23.