276 The Lymphocyte and Lymphocytic Tissue 



the reticular lymphoblasts as found in normal lymphocytopoiesis (Fig. 

 19-11). instead of resembling myeloblasts. This finding necessitates recog- 

 nition of the possibility of encountering reticular lymphoblasts in an occa- 

 sional case of lymphocytic leukemia in place of the lymphoblasts resembling 

 myeloblasts in the ordinary case of acute lymphocytic leukemia. The former 

 finding is especially true when hematopoietic RE cells are directly involved 

 in the leukemic process together with the lymphoblasts (lymphocytic leu- 

 kemic retic uloendotheliosis). 



Fig. 19-12. Lymphoblasts (left), lymphocyte (center), and prolympho- 

 cytes (right) in a lymph node imprint in lymphosarcoma, lympho- 

 blastic cell type. Leishman stain, (x 1100) 



In our experience the lymphoblasts of malignant lymphoma or lympho- 

 sarcoma of the lymphoblastic cell type (imprinted in Fig. 19-12) more closely 

 resemble reticular lymphoblasts. 



We are now in a position to appreciate the additional fact that bizarre 

 or malignant nuclear lobulation or indentation at times can be super- 

 imposed either on the leukemic lymphoblast with myeloblast-like nuclear 

 pattern or on the reticular lymphoblast whether it is leukemic or lym- 

 phomatous. Because of the foregoing, the leukemic lymphoblast presents 

 itself in the peripheral blood with bizarre nuclear indentation or without 

 it, with a myeloblast-like nuclear pattern or with one resembling a reticulum 

 cell nucleus, heavily nucieolated, moderately nucleolated, or with masked 

 nucleoli. Rather than designate cells exhibiting one or the other of these 

 unusual structural features as "lymphosarcoma" lymphoblasts, we prefer to 



