Yoshiro Ebihara

LYMPHOMATOID GRANULOMATOSIS (LIEBOW)

An autopsy case with pulmonay lesions analogous to Liebows lymphomatoid granulomatosis (LYG) and some other unusual pictures were reported. A 29‐year‐old male who had been diagnosed and treated as Sjögrens syndrome for eleven years because of intermittent swelling of the parotids with diffuse lymphoid cell infiltration and positive serum RA‐test, showed several circumscribed densities on the chest X‐ray examination which were deemed to be of interlobar pleurisy. On autopsy, the nodular lesions in the lung were composed of angiocentric‐angiodestructive lymphoid cell proliferation analogous to LYG. In addition, the present case was characterized by focal glomerulonephritis and splenic trabeculitis which are quite unusual associations in LYG. The relationships of the present case to other similar diseases such as Wegeners granulomatosis, Sjögrens syndrome, primary lymphoma of the lung, etc. were discussed.

Histological and Electron Microscopic Study of Human Cases

Four autopsy cases of mesothelioma were studied histologically and electron microscopically. One of them showed a pure epithelial type of the peritoneal origin, characterised by a tremendous production of hyaluronic acid. The other three tumors originated from the pleura revealed a histology of biphasic type mesothelioma, which showed an admixed tubular and fibrous pattern and consisted of small‐sized cells with slight atypia. However, in some places of these tumors they showed considerable atypical features appearing like an anaplastic or squamoid carcinoma and/or spindle cell sarcoma. Hyaluronic acid was histologically demonstrated in the cytoplasmic vacuoles as well as in the luminal space surrounded by the tumor cells. Electron microscopically, varied numbers of microvilli and desmosome‐like attachments were found on the surface of the tumor cells. Mitochondria were small and round. Well‐developed rERs tended to encircle mitochondria and to dilate forming cisternae. Various amounts of microfilaments were found in the cytoplasm. The tumor cells which were rich in the latter two components, dilated rERs and microfilaments, resembled fibroblasts. Some tumor cells had phagosomes including dense and fine granules similar to ferritin, suggesting their phagocytotic activity. The hyaline matrix, common to the biphasic type tumor which was largely composed of dense collagenous tissues, was demonstrated to contain hyaluronic acid by histochemistry, and it was suggested that some secretory substances of the tumor cell may participate in composing the hyaline matrix to some extent. ACTA PATHOL. JPN. 34: 1411–1424, 1984.

GIANT CELL PNEUMONIA IN LETTERER‐SIWE DISEASE

An 8‐month‐old girl suffered from Letterer‐Siwe disease since one week after birth. During the chemotherapy, giant cell pneumonia caused by measles virus infection developed and led rapidly to her death. Histopathologically, alveolar spaces were lined by multi‐nucleated giant cells with intranuclear and intracytoplasmic eosinophilic inclusion bodies. Electronmicroscopical examination of the lung revealed intranuclear inclusion bodies full of rod‐shaped structures characteristic to paramyxoviruses, and irregular electron‐dense materials compatible with nucleocapsid protein antigens in the cytoplasm. Additionally these giant cells were observed in the salivary glands, thyroid gland, thymus and lymph nodes. The measles virus antigen was detected immunohistochemically in these giant cells in the lungs and other organs. The specific antibody of measles virus is helpful to study the pathogenesis of giant cell pneumonia.