Abstract. Griesshammer M, Bangerter M, Sauer T, Wennauer R, Bergmann L, Heimpel H (University of Ulm, Germany). Aetiology and clinical significance of thrombocytosis: analysis of 732 patients with an elevated platelet count. J Intern Med 1999; 245: 295±300.Objective. To determine the aetiology and clinical significance of an elevated platelet count (thrombocytosis) in a large cohort of patients. Design. A retrospective review of the medical records was performed on all patients, who had at least one platelet count $ 500 3 10 9 L -1 . Setting.

There were characteristic modes of discordance between ZAP-70 and VH mutation status depending on the presence or absence of additional genetic high-risk features such as 11q and 17p deletion or V3-21 usage. Although the biologic background for these findings is yet to be determined, these data have biologic and clinical implications regarding ZAP-70 as a pathogenic factor and outcome predictor, respectively.

FDG PET may be more accurate for detecting nodal lymphoma than incremental CT.

The results indicate that FDG-PET has a high potential to detect bone marrow involvement in malignant lymphoma. Besides confirming lesions found at BMB, FDG-PET provided additional information, which, in eight of 78 patients (10.3%), led to an upgrade of the tumor stage.

Our data indicate that FDG-PET provides an imaging technique that appears to visualize involved lesions in most patients with HD and is useful in the management of these patients.