Tokio Takeuchi

Primary Hodgkin's disease of the bone presenting with an extradural tumor

We report a very rare case of primary Hodgkins disease of the bone in a 56-year-old male. It presented with sudden onset of paraparesis which suggested an extradural tumor. Early appropriate therapy for similar patients with Hodgkins disease can improve their prognosis.

Primary cutaneous CD5+ marginal zone B-cell lymphoma resembling the plasma cell variant of Castleman's disease. Case report.

Marginal zone B‐cell lymphoma (MZBL) is occasionally associated with prominent plasma cell differentiation. However, MZBL rarely exhibits histological features that resemble plasmacytoma arising from a localized plasma cell variant of Castlemans disease (PCCD). We here report a histologically similar case that was associated with primary cutaneous tumor. The patient was a 57‐year‐old woman with a 5‐year history of cutaneous nodules. Histologically, a prominent proliferation of plasma cells occupied the interfollicular area of the central portion of the cutaneous tumor, whereas various numbers of CD5+ centrocyte‐like (CCL) cells, which were arranged in a marginal zone distribution pattern, occupied the peripheral region of the tumor. The majority of the lymphoid follicles had atrophic or regressive germinal centers resembling hyaline‐vascular Castlemans disease. CCL cells were observed to have colonized a few of the lymphoid follicles. Immunohistochemistry revealed that these cells had a monotypic intracytoplasmic kappa chain. Without treatment, the patient was quiescent, but 2 years later, there was a transformation to the large cell type. These observations suggest that MZBL needs to be distinguished from PCCD, and that untreated cutaneous MZBL may undergo a high‐grade blastic transformation similar to other indolent lymphoproliferative disorders.

Role of blood platelet in the formation of thrombus

Abstract In the busulfan-induced thrombocytopenic rabbits, the femoral artery was completely occluded after injection with ellagic acid at the site of stenosing ligature in 5 out of 15 rabbits, while in the control rabbits with normal platelet count, a large thrombus was present around the stricture in 12 out of 17 rabbits. Occluding thrombus was produced in only 2 out of 15 rabbits which ingested more than 0.05 g of aspirin 6 hours before surgery. Rate of occluding thrombus formation on the chemically intimectomized femoral artery with diluted sulfuric acid was evidently high in the rabbits with rebound thrombocytosis after transient thrombocytopenia induced by intravenous injection with anti-platelet serum. In the case of stasis thrombus formation, both in thrombocytopenic rabbits and in aspirin-ingested rabbits, percentage of rabbits producing the thrombus was not significantly different from that of the control. From the results described above, it is suggested that both quantitatively and qualitatively normal platelets are required for the production of arterial thrombosis. On the other hand, blood platelets may not contribute to the formation of stasis thrombosis.