PROTOZOA AND THE CANCER PROBLEM 211 



been held responsible by one or more investigators, but in no case 

 have the claims been made good. Not only protozoa, but yeasts and 

 bacteria, and still other forms of living things, have been drawn into 

 the vortex of a discussion over the parasite theory when that discussion 

 was more spirited than it is today. Many of the structures thus inter- 

 preted as organisms are characterized by surrounding shells or cap- 

 sules which some investigators have interpreted as parts of an invading 

 organism (Fig. 85 2, 3). Cell invasions, however, are common in cancer 

 tissue, leukocytes, or even cancer cells themselves, invading other cells 

 and there degenerating or causing degeneration, while the capsules are 

 only condensations of the invaded protoplasm. This is the view 

 adopted by Sjobring ('02), Sawtschenko ('95), RufPer and Walker 

 ('93), and many others, while numerous observers have described the 

 successive changes in the degeneration of the contained leukocytes 

 and interpreted the various "organisms" that had been described as 

 merely one form or other of such degenerating cells (Fig. 85). One 

 type of these inclusions, on account of its minute size, characteristic 

 structure, and occurrence, was designated the "X-body" by Behla 

 ('03), and was regarded as different from other cell inclusions which 

 were due to degeneration. This "body" occurs under many different 

 forms and has been variously interpreted (Fig. 85, 12, 14, 15, 18). 

 It is known in literature as the "Plimmer body," as the "bird's-eye 

 inclusion," as the astrosphere or centrosphere of Borrel ('01), as the 

 "cancer parasite" of Bosc ('98), the "plasmodiophora-like bodies" of 

 Gaylord, as "Histosporidium carcinomatosum" of Feinberg ('03), as 

 the "intracellular secretions" of Nosske ('02) and Greenough ('01), 

 as "chytridia;" of Behla ('03), as the "yeast cells" of San Fehce ('98) 

 and others. Pianese ('96), Sawtschenko ('95), Soudakewitsch ('92), 

 Ruffer ('92), and others observed similar bodies inside the nuclei of 

 cancer cells, and interpreted both these and the cytoplasmic forms as 

 colloidal degenerations of the chromatin and cytoplasm, Sawtschenko 

 regarding them as masses of food material for the real parasite. 

 Calkins ('05) described stages leading to the conclusion that all of 

 such bodies are derived from the degenerating nucleoli of the cancer 

 cells, these nucleoli first becoming clathrate, irregular in outline, and 

 surrounded by local thickenings of chromatin or cytoplasm. Other 

 forms, however, might better be interpreted as blood platelets or 

 portions of leukocytes having the power to move from cell to cell 

 (Fig. 85, 13, 17), but in no case is there evidence to regard them as 

 specific organisms. 



While these cell inclusions in human cancer cannot be interpreted 

 as organisms, it does not follow that real organisms are not present. 

 Later stages of the disease are particularly suitable for secondary 

 infection, and exposed surface lesions form a suitable medium for the 

 growth of bacteria, yeasts, or protozoa, while in one case of epithe- 



