526 THE CHEMISTRY OF TUMORS 



variety of tumor differs from the standard types of malignant tumors 

 in thac it involves the marrow of many bones simultaneously, in a very 

 diffuse manner, without usually giving evidence of a true metastasis. 

 In many respects it resembles the leukemias, pseudoleukemia, and 

 chloroma, and it is extremely uncertain as to where in the classifica- 

 tion of tumors and of the diseases of the blood-forming organs this 

 disease should be placed. Histologically, the tumors show evidence of 

 being derived from the specific cells of the marrow, either from the 

 plasma cells (Wright) or from the neutrophile myelocytes-^ or their 

 predecessors (Muir). Cases of myeloma without the proteinuria 

 have been described, and also a few instances of the presence of 

 apparently typical Bence-.Iones protein in the urine without myelomas, 

 but with bone carcinomas, leukemia or chloroma.-'' 



Properties of the "Bence=Jones Protein." — Not to go into 

 details, which are given in the hterature cited, the important facts con- 

 cerning the " Bence-Jones protein," and its appearance in the urine 

 {"myelopathic albumosuria," Bradshaw), are as follows: 



It is a protein, the exact nature of which has not been determined; 

 at first considered an albumose because of its peculiar reactions to 

 heat, its nature has since been contested, but the weight of evidence 

 seems to be in favor of the contention of Simon that it is most closely 

 related to the water-soluble globuHn of the blood. In certain cases 

 it partly precipitates spontaneously from the urine," and it may 

 crystallize in the renal tubules. ^^ Its most characteristic properties 

 are the following: 



The coagulation temperature is low, varying from 49°-60° in various cases, 

 and being considerably modified by the amount of salts and urea present in the 

 solution. Probably the protein forms a molecular compound with the salts 

 which is more stable at 100° than at lower temperatures (Hopkins and Savory). 



In many cases the coagulum is redissolved on heating, and reappears on cool- 

 ing, but this characteristic feature is not always present, and often disappears in 

 cases where at first it is present. 



A precipitate is formed by strong (25 per cent.) nitric acid, which disappears 

 on heating and reappears on cooling. Strong hydrochloric acid causes a dense 

 precipitate, which is quite typical (Bradshaw). 



No precipitate is produced by acetic acid, even in excess, and the addition of 

 acetic acid to a hot coagulated specimen causes prompt solution of the coagulum. 



UnUke albumoses, this substance does not dialyze; the salt-free solution left 

 in the dialyzing bag does not precipitate. 



A purplish-violet color is usually given with the biuret reaction, but it may 

 be more reddish in color, especially if little copper is present. 



" Forman and Warren (Jour. Cancer Res., 1917 (2), 79) found the cells to con- 

 tain granules giving the indol-phenol blue reaction and hence belonging to the 

 myeloid group. 



^'^ Glynn has described a glycoprotein resembling Morner's body, in the urine 

 during myeloma (Liverpool Med. Chir. Jour., 1914, p. 82). A crystallizable pro- 

 tein, resembling the Bence-Jones body, has been found in the urine of a woman 

 with gastric cancer without any bone involvement (Schumni and Kimmcrle, Zeit. 

 physiol. Chem., 1914 (92), 1). 



" Rosenbloom, Arch. Int. Med., 1912 (9), 255. 



" Loehlein, Cent. allg. Path., 1913 (24), 953. 



