26S 



The Lymphocyte and Lymphocytic Tissue 



mononuclear reticulum cell depicted at the bottom of Figure 19-5. These 

 background, malignant mononuclear cells bear a striking resemblance to 

 the reticulum cells of reticulum cell sarcoma depicted in Figure 19-4. They 

 are large in size and may present beginning lobulation of their nucleus. 

 Their chromatin is arranged in small angular pieces but with distinct, inter- 

 vening, colorless parachromatin spaces. The nucleoli, unlike their large, 

 acidophilic counterparts in sectioned material, are small, round or irregular, 





Fig. 19-6. Imprint from supraclavicular lymph node showing 

 metastatic tumor cells from E wing's tumor in clavicle. Note resem- 

 blance to reticulum cells. Leishman stain, (x 1100) 



and deeply basophilic. The cytoplasm is irregularly basophilic and moder- 

 ately abundant. Binucleation of such cells leads to formation of the so- 

 called mirror-image reticulum cells. Lobulation of the nuclei of these malig- 

 nant reticulum cells in Hodgkin's disease increases until the nucleus is 

 giant, bizarre, and polymorphous (center of Fig. 19-5). It is to be noted 

 that the fine reticular chromatin network with its chromatin-parachromatin 

 distinction is retained in the fully developed Reed-Sternberg cell. In im- 

 prints it will often be seen that each nuclear lobe is spotted with from six 

 to eight small, basophilic nucleoli instead of the one or two large acido- 

 philic nucleoli observed in histologic sections. However, even in imprints 

 the nucleoli may reach diameters up to 7 p. but they retain their deeply 

 basophilic staining properties. 40 The cytoplasm is abundant and consists of 

 flaky or granular basophilic material against a colorless background. 



