Henry A. Azar

Diffuse large cell lymphomas (reticulum cell sarcomas, histiocytic lymphomas). Correlation of morphologic features with functional markers

Electron microscopic findings in 15 cases of diffuse large cell lymphoma were correlated with other morphologic features, surface immunotype and cytoplasmic immunoglobulin content. Immunologically, the cases were: B cell, 8; null, 4; T cell, 2; and H cell (true histiocytic), 1. Ultrastructurally, all B cell and three null lymphomas were characterized by an abundance of polyribosomes and segments of rough endoplasmic reticulum. Concentric rough endoplasmic reticulum was observed in 4 cases of B cell lymphoma containing cytoplasmic immunoglobulin and in a null lymphoma. In 1 case of B cell lymphoma, the diastase‐sensitive, periodic‐acid‐Schiff‐positive cytoplasm showed evidence of widely dispersed monoparticuiate glycogen granules. The two T cell lymphomas contained hyperlobulated or single round nuclei, and abundant smooth to rough endoplasmic reticulum. One null lymphoma appeared to share the ultrastructural features of T cell convoluted nuclei and the cytoplasmic organelles of myeloid precursor cells. The H cell lymphoma had features of monocytic‐macrophagic differentiation. The large cell lymphomas, a morphologically and functionally heterogeneous group, were represented predominantly in this series by neoplasms with follicular center cells or early plasma cells.

Nuclear and Cytoplasmic Inclusions in Disseminated Human Cytomegalovirus Infection

A case of disseminated human cytomegalovirus infection is described in a full-term female who expired 3 1/2 h after birth. Cytomegalic inclusions, both intranuclear and intracytoplasmic, were observed mainly in the kidneys, liver, lungs, and anterior pituitary but were not seen in the bone marrow and spleen. Whereas the nuclear inclusions consisted of an amorphous filamentous meshwork with a variable number of pleomorphic capsids, the cytoplasmic inclusions were composed of membrane-bound aggregates of mature virions with dense cores and multilayered envelopes. The complex envelopment process of cytomegalovirus appears to involve successive coats derived from the nuclear membrane and from the endoplasmic reticulum or cytoplasmic vesicles.

Plasma levels of a squamous cell carcinoma-associated antigen in athymic nude mice bearing human squamous cell carcinoma xenografts of oral origin: With preliminary clinical data

A human squamous cell carcinoma (SCO) of oral origin was transplanted into athymic mice that were then divided into six groups. The mice were killed at 1 to 6 weeks after tumor transplantation; the sixth group was killed 1 week after excision of SCC grafts. Plasma samples were obtained from each mouse at the time of death for the determination of SCC‐associated antigen (SCCAA), a cytoskeletal protein fraction of about 48,000 daltons originally derived from SCC of the uterine cervix. The plasma SCCAA level rose gradually and proportionately to the growth of SCC xenografts from a baseline of 0.66 ng/ml [standard error (SE) + 0.12] to the preoperative peak of 8.44 ng/ml (SE + 1.86) at 5 weeks, to fall precipitously to the postoperative level of 1.05 ng/ml (SE + 0.27) at 6 weeks. No rise in plasma SCCAA level was observed in mice bearing a human malignant melanoma, and only modest rises were observed in mice bearing human adenocarcinomas and oat cell carcinoma. In this experimental model rising plasma SCCAA levels were found to be dependable indicators of SCC tumor growth. These observations and preliminary data on SCCAA levels in patients with or without SCC of the head and neck lend support to the clinical usefulness of serial plasma SCCAA determinations in monitoring patients with SCC of the oral cavity.