CHEMISTRY OF BEXKIX TUMORS 513 



Chemistry of the Mucoids of Ovarian Cysts. — Pseudormuin lias tlie following 

 ■elfiucntaiy compositiuii : C, 4!).75; II, (i.ilS; X, 10.2S; S, 1.25; 0, 31.74 per cent. 

 ( Hammarsten) . In eoimnon with the true mucins it yields a sugar-like reducing 

 body, which has been investigated by numerous chemists (Miiller, Panzer, 

 Zangerle, Ix^vthes, Neubcrg, and ileymann^s). Panzer considers that this re- 

 ducing substance is in the form of a sulphuric-acid compound, similar to, but not 

 identical with, chondroitin-sulphuric acid. Hammarsten, however, did not find 

 this substance constantly present. Leathes determined for the carbohydrate group 

 the composition C,;lL:,NOi„, named it ''paramucosin," and considers it a reduced 

 <^houdrosin (which is the carbohydrate group of chondroitin-sulphuric acid). 

 Neuberg and lleymann established, however, that tlie reducing body must come 

 from chitosainin (CjHi-iNO.-,) , and do not consider paranuicosin a constant con- 

 stituent of ovarian mucoids. The amount of reducing substance varies greatly 

 in the mucoids found in different cysts; in some the mucoid yields but about 

 3 to 5 per cent., in others as much as 30 or 35 per cent., of reducing substance. 



Psendomucin dissolves readily in weak alkalies, and differs from true mucin 

 in that it is not precipitated by acetic acid, and from the simple proteins in that 

 its solutions are not coagulated by boiling. With water a slimy, stringy semi- 

 solution is formed, resembling in appearance the material found in ovarian cysts. 

 Leathes distinguishes two forms of ovarian mucoids: (3ne, paramucin, occurs as 

 a firm, jellj'-like substance, which is converted by peptic digestion into the easily 

 soluble pseudomucin. Ovarian "coUoid" probably consists of a thickened pseudo- 

 mucin. often mixed with other proteins. Pfannenstiel 32 considers the "colloid" 

 material as representing a modified pseudomucin, strongly alkaline and relatively 

 insoluble, which he calls "pseudo-mucin /3." He also describes a very soluble 

 mucoid found only in certain ovarian cysts, naming it "pseudo-mucin 7." 



The reasons why these variations in the pseiidomucins exist is not 

 understood ; they cannot be explained as due to variations in the cell 

 type in the cyst wall, althoug-h pseudomucin is probably the result of 

 true secretion. The smallest cavities of ovarian cystadenomas con- 

 tain nearly pure pseudomucin, which presents a clear, glassy struc- 

 ture ; the larger the cysts become, and the more turbid and thinner 

 the fluid is, the more simple are the proteins it contains. True mucin 

 is never present in ovarian cysts. Pseudomucin occurs only in the 

 glandular proliferating cystomas and the papillary proliferating 

 cystadenomas, in the former appearing constantly and abundantly, in 

 the latter not constantly and never abundantly (Pfannenstiel) . Paral- 

 humin (Scherer) is a mixture of pseudomucin with variable amounts of 

 simple proteins. Metalhumin (Scherer) is the same body that is called 

 pseudomucin by Hammarsten. Paramucin (Mitjukoff) ^^ is a mucoid 

 differing from mucin and pseudomucin in reducing Fehling's solution 

 directly, without having the carbohydrate group first split off by 

 boiling with an acid. Hj^drolysis of paranuicin by Pregl ^'' showed an 

 absence of glycocoll, but traces of diamino-acids, and the presence of 

 leucine, alanine, proline, aspartic and glutamic acids, tryptophane 

 and tyrosine. 



Substances similar to pseudomucin have been occasionally found in 



cancerous ascitic fluid and in cystic fibromyoraas (Sollmann) ; and 



they are abundant as constituents of the contents of the peritoneum 



33Hofmeister's Beitr., 1902 (2), 201 (literature). 

 35 Arch. f. Gynaek.. 1805 (40), 278. 

 seZeit. physiol. Chem., 1908 (58), 229. 



33 



