Shojiroh Morinaga

Plasmacytoma of the lung associated with nodular deposits of immunoglobulin

A case of extramedullary plasmacytoma of the lung associated with nodular immunoglobulin deposits is presented. The main tumor was located in the posterior basal segment of the lower lobe of the left lung and showed intrabronchial polypoid growth. Multiple metastatic tumors were observed in regional lymph nodes and the visceral and parietal pleura. Histologically, the tumor was composed of sheets of plasma cells with mild atypia. A large amount of amorphous material resembling amyloid was observed in the tumors, and was more marked in the metastatic lesions. Immunohistochemically, the tumor cells were shown to contain monoclonal IgG-kappa immunoglobulin. The amorphous deposits were not identical to amyloid since congo red stain was negative and amyloid fibrils were not observed ultrastructurally. By Western blotting, immunoglobulin (IgG, kappa) was identified as the major component in an extract from the nodular deposits. In the preoperative serum from the patient, M-protein (IgG-kappa) was detected by immunoelectrophoresis. Bone marrow examination revealed no abnormality.

Low-grade mucinous cystadenocarcinoma in the spleen.

A 69-year-old man with an enlarged spleen, found by computed tomography scan to be multicystic, underwent a splenectomy. Pathological examination revealed a Low-grade mucinous cystadenocarcinoma that was histologically analogous to a mucinous tumor of the ovary. The serum level of tumor markers carcinoembryonic antigen (CEA)and CA19-9 were elevated preoperatively and returned to normal after the operation. In the absence of a primary tumor elsewhere, we considered this tumor to be primary in the spleen, and it was presumed that the tumor arose either from invaginated capsular mesothelium of the spleen or from heterotopic pancreatic or enteric tissue within the spleen.

Multiple thymic squamous cell carcinomas associated with mixed type thymoma.

A 49-year-old woman was admitted to the hospital because of abnormal shadows on a chest roentgenogram that suggested enlargement of bilateral hilar and mediastinal lymph nodes. Chest surgery was performed after a diagnosis of malignant thymoma that was following a left supraclavicular lymph node biopsy. The tumor consisted of several nodules, the largest of which was 6.5 cm. One nodule had invaded the pericardium and left upper lobe of the lung. Metastases to the peribronchial and mediastinal lymph nodes were present along with implantation on multiple pleural sites. Histological examination revealed that the tumor was of a mixed type with features of thymoma and squamous cell carcinoma, and that these two histological types were present in the same nodule with gradual transition between the two. Immunohistochemical surface marker studies revealed that lymphocytes in the squamous cell carcinoma were of the peripheral blood type. We conclude that squamous cell carcinoma may originate in the epithelial cells of a thymoma.

Malignant transformation of sialadenoma papilliferum of the palate: a case report.

We report a case of a 79-year-old woman with an unusual salivary gland tumor that developed at the junction between the soft and hard palates. The tumor consisted of sialadenoma papilliferum (SP) with areas of an epithelial–myoepithelial carcinoma (EMC) component and a high-grade carcinoma component. There were also transitional regions among the SP, the EMC and the high-grade carcinoma components. The high-grade carcinoma component, which was similar to invasive micropapillary carcinoma of the breast, infiltrated into the right parapharyngeal space and metastasized to the lungs and cervical vertebrae. The high-grade carcinoma cells were positively immunostained for p53 protein. SP has been considered to be a benign tumor with exceptionally good prognosis, and, to the best of our knowledge, there has never been a confirmed case of malignant SP. This is the first report of SP with a definite malignant component.

Biological, pathological and clinical features of small cell lung cancer

Small cell lung cancer, which is not uncommon, and is one of the most malignant and relatively well investigated solid tumors of adults, has been reviewed concerning its biology, pathology and clinical aspects. Although it is histologically very simple, its poorly differentiated epithelial cell characteristics are complicated by features of neuroendocrine cells, such as amine and peptide hormone production and specific enzyme activities, some of which have been found to be good monitoring markers during and after treatment. Because of the relative ease of establishing cell lines in vitro, cell characteristics have been studied in detail. This has led to subtyping of cell lines and may further lead to subtyping of histology. However, accumulation of further evidence has disclosed exceptions and unclassifiable cell lines. The same can be said about chromosomal abnormality. The reactivity of monoclonal antibodies and also oncogenes supports the prevalent concept discriminating small cell cancer from non-small cell cancer. However, concepts concerning histogenesis are still changing. Although it is one of the solid tumors most sensitive to radiation and chemotherapy, the response rate of the tumor to non-surgical treatment appears to have reached a plateau. In order to make a breakthrough in the treatment, strategies based on biological findings must be applied.

Morphological variation of immunoreactive cells positive to cholecystokinin 33 (10–20) and gastrin 34 (1–15) in human duodenum

SummaryHuman duodenal endocrine cells reactive with antibodies to cholecystokinin (CCK) 33 (10–20) and/or gastrin 34 (1–15) were studied by a combination of immunohistochemical and electron-microscopic methods. By immunohistochemistry, three types of endocrine cells were distinguished in human duodenal mucosa, i.e., those only positive for only CCK, those positive for both CCK and gastrin and those only positive for only gastrin. Ultrastructurally, the first cell type is characterized by many secretory granules with an eccentric dense core (mean diameter; 271+-74 nm). The second cell type, which was less frequent than the other two, has ultrastructural features that resemble type-I cells. The last cell type was composed of two types of cells containing small secretory granules identical to those of IG cells (mean diameter; 171+-31 nm) or large secretory granules indistinguishable from those of I cells (mean diameter; 286+-50 nm).

Malignant pleural mesothelioma producing human chorionic gonadotropin. Report of two cases.

Two cases of malignant pleural tumor producing human chorionic gonadotropin, one confirmed at surgery and autopsy and the other by biopsy, are reported. Both of the patients had bilateral gynecomastia with high levels of serum human chorionic gonadotropin. The first patient underwent panpleuropneumonectomy because of diffuse malignant pleural tumor, but died five months later due to recurrent disease. The histological diagnosis was diffuse, malignant, monophasic mesothelioma of the epithelial type. Immunostaining for a-, p-human chorionic gonadotropin and human placental lactogen was positive in syncytiotrophoblast- like cells. The second patient had diffuse pleural tumor with massive effusion. A pleural biopsy specimen showed diffuse proliferation of epithelioid large cells. Immunostaining for a, @-human chorionic gonadotropin and human placental lactogen was positive in mono- and multinucleated bizarre giant cells mimicking trophoblasts. A diagnosis of malignant mesothelioma with trophoblastic differentiation seemed most likely in both cases in view of the clinical and pathological findings. In both cases, results of mucin histochemistry and various immunohistochemical stains for antigens or with antibodies were consistent with diagnosis of mesothelioma except in a few cells in the choriocarcinomatous portion. This may be the first report describing human chorionic gonadotropin-producing malignant mesotheliomas of the pleura.

CILIATED-CELL ADENOCARCINOMA OF THE PANCREAS

An autopsy case of ciliated‐cell adenocarcinoma of the pancreas was reported. A 65‐year‐old man, who had undergone subutotal gastrectomy because of advanced gastric carcinoma 6 years previously, died of obstructive jaundice. The autopsy revealed a primary tumor in the head of the pancreas and multiple metastatic foci in the liver, lungs, and regional lymph nodes. Histologically, the pancreatic tumor was moderately differentiated papillary adenocarcinoma with well developed cilia. The metastatic tumor also showed similar histology. Histologic and ultrastructural features of the tumor were described in detail and the cytogenesis of ciliated‐cell adenocarcinoma was briefly discussed.

High Concentrations of Enolase, α- and γ-Subunits, in the Aqueous Humor in Cases of Retinoblastoma

Because retinoblastomas contain a large amount of the γ-subunit of enolase or neuron-specific enolase, we studied the aqueous humor levels of the γ-subunit and α-subunit in 12 cases of retinoblastoma. Enzyme immunoassay demonstrated that both the γ-subunit and the α-subunit were greatly increased in all 12 (minimum levels, 87.8 ng/ml and 354 ng/ml, respectively). Thus, aqueous enolase levels, especially that of the γ-subunit, are useful in the diagnosis of retinoblastoma and may be useful as monitoring markers in retinoblastoma involving the central nervous system.

Hamartoma of the parotid gland: A case report with immunohistochemical and electron microscopic study

A case of a solid parotid tumour in a 16-year-old boy is presented. Histologically, the tumour demonstrated some peculiar findings. An acinar pattern was predominant although every component seen in the normal salivary gland was present, namely, serous and mucous gland acini, ducts, myoepithelial cells, adipose and lymphoid tissue. Large eosinophilic granules were abundant in the large acinar cell cytoplasm. Immunohistochemically, the tumour demonstrated the proteins which are present in the normal parotid gland, for example, amylase, lactoferrin and lysozyme. Electron microscopic features were quite similar to those of normal parotid tissue except for accumulation of a large number of cytoplasmic granules in the acinar cells. There has been no previous report of a tumour with the same features as seen in this case. Our pathological diagnosis is hamartoma, although the possibility of hyperplasia or neoplasia can not be excluded.