FIELD E; Tumor Code 



Columns 18, 19, 20, 21, 



22, 23, 24, and 25 



Each Field E symbol for a specific tumor is the result of a tumor coding procedure described by 

 the diagram of the previous page and the following paragraphs, just as a total code line of chemical- 

 biological data is the result of a coding procedure using all coding fields. (See also the second para- 

 graph of the section on Organization, in the General Discussion of Field E. ) Any tumor not previously 

 coded by the CBCC is coded by the procedure described below and is added to the tumor list in the 

 Code. Therefore, when coding chemical-biological data involving that tumor, its symbol is quickly 

 available, not only sparing coders from repeatedly having to code the tumor (i. e. , prepare the code 

 symbol), but assuring uniformity when coding chemical-biological information on that specific tumor. 



2. Part I of the tumor symbol (first unit, Column 18): identification of the symbol as a tumor 

 symbol 



Of the eight places in the tumor symbol (for the eight columns of Field E), the first is used 

 merely to distinguish all tumor symbols from any other entry in Field E (i. e. , from symbols for test 

 organisms and for non-infective diseases). Thus, by retrieving from a file of coded data all Field E 

 entries with this first unit (Symbol S) which is common to all tumor symbols, all information on tumors, 

 but only on tumors, can be obtained. Since tumors are coded in the same field in which organisms as 

 well as pathologies are coded when appropriate, this first identifying part is essential. However, it 

 might be pointed out that, were tumors to be given a separate coding field (impractical as far as CBCC 

 coding facilities are concerned) or if only tumor data were coded, Part I would be unnecessary. 



As the diagram indicates, the remaining four parts of the Tumor symbol describe and identify 

 the tumor. 



3. Part II of the tumor symbol (2nd and 3rd units, Columns 19 and 20): gross anatomical tumor 

 origin (organ or system ) 



This independent, two-unit part of the symbol signifies the organ or organ system from which 

 the tumor originated and it is referable to a separate code scheme for these organs or organ systems. 

 Unlike the anatomy part of symbols of the CBCC Pathology Code, these anatomical symbols included 

 in the Tumor Code symbol are not to be found in the code list of anatomical items for Fields H- 1 and 

 H-2, but only in the special list included in the Code accompanying the list of tumors. This special 

 anatomy code consists of a first unit, indicating the system of which the organ is a part, and a 

 second unit, which is merely a sequential number assigned to each organ of that system. 



For the most part, organs (and tissues) of one chordate animal group are homologous to the 

 organs (and tissues) of any other chordate group so that the same symbols are applicable to all 

 Chordata. Organs and tissues of invertebrates (insects, e. g. ) are scarcely homologous to chordate 

 organs and tissues, but these may be inserted in the list as specific invertebrate organ or invertebrate 

 tissue items under the appropriate organ or tissue system of the list. Since so few invertebrate tumors 

 may be expected to be chemically treated, experimentally, it is consequently expected that all such 

 symbols needed (for invertebrate organ and tissue tumor origins) can be adequately accommodated by 

 available symbol combinations. 



Thus, complete tumor symbols do not have any specific unit which indicates from which animal 

 or animal taxonomic group the tumor originated. However, since tumors are seldom if ever transplanted 

 to an animal of a phylum or class different from that of the tumor's origin, the phylum or class of the 

 animal from which the tumor arose will be indicated in Field J (the tumor host). Rare exceptions to 

 this occur in tissue culture studies (e. g. , a mouse tumor explanted to a chick embryo), in which case 

 the animal in which the tumor originated is merely recorded in the written portion of Field E. See also 

 the General Discussion of Field E, Division 1 of the special section on Specific Directions and 

 Explanations for Tumors. 



If the CBCC Code were adopted for recording data from tumor tests especially or exclusively, 

 a new field might be established for recording the specific organism in which the tumor originated, if 

 different from the host coded in Field J. For example, such a field would be desirable if data were 

 being recorded from tests dealing solely with attempts to establish tumors of one species or genus in 

 another species or genus. Since the CBCC Code is designed exclusively for testing chemicals (as 

 carcinogens or carcinostats, e. g. ), there is little anticipated need for identifying the organism in 



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