FIELD_E; Tumor Code 



Columns 18, 19, 20, 21, 



22, 23, 24, and 25 



For any given tumor type (indicated by units 1 through 7 of the tumor symbol), there may be several 

 or many specific tumors which must be distinguished by unique symbols in the eighth place. Symbols 

 1 through 9 and A through Z in the eighth place permit unique code symbols for 35 specific tumors. 

 In most cases, this is more than adequate provision. If more than 35 occur, however, and must be 

 assigned symbols, they can be accommodated only by the procedure as described in the division 

 immediately following. 



7. Construction of symbols for specific tumors of identical organ- tissue origins, when more 

 than 3 5 such tumors must be included in the Tumor Code 



When there are more than 3 5 specific tumors with identical organ and tissue-type origins, the 

 SEVENTH unit, coding that tissue type, may be combined (on the IBM punched card) with a zone punch 

 (which will make it a corresponding letter designation) and the sequential numbering of the EIGHTH 

 place repeated for the next thirty-five tumors of that tissue-type. In the present tumor list, this 

 occurs only once, in the case of mammary gland adenocarcinomas. After the 35th adenocarcinoma was 

 listed (Symbol S911121Z), the 12 zone punch was added to the seventh unit (Symbol 1), which converted 

 it to the corresponding letter (Symbol A) and sequential numbering and lettering was begun again in the 

 eighth place; thus, the symbol for the 36th adenocarcinoma is S91112A1. In this example, by using 

 both the 11 and 12 zone punches for combinations, it is possible to accommodate 105 mammary adeno- 

 carcinomas in the list. (It happens that Symbol 1 can not be meaningfully combined with the IBM 

 zone punch, though other numerical symbols, 2-9, can; see the following paragraphs. ) By this means, 

 information on a_ll mammary adenocarcinomas can be retrieved from a file of coded data by sorting solely 

 on the Symbol S911121, ignoring the zone punches, while information on any given mammary adeno- 

 carcinoma can be found by sorting on its specific symbol, including any zone punch designation. (In 

 this example, it should be noted that the letter designations formed by using the zone punches [letters 

 A and J, formed by combining Symbol 1 with the two zone punches in turn] can not subsequently be 

 used again as distinguishing seventh units for symbols for tumors of the type coded by the six- unit 

 symbol, S91112--. For this reason, only numerical symbols 1 through 9 are used as a seventh unit 

 [except as a continuation, as just described] in listing specific tumors of a given organ-tissue type. ) 



In the case of the seventh unit being any numerical symbol other than 1 ( and , discussed in 

 the next paragraph), that symbol can be combined with the zone punch as well as with the 11 or 12 

 zone punches so that 140 specific tumors of a given organ-tissue source are possible in the list. 

 (E. g. , combining Symbol 2 with all zone punches in turn makes possible a set of 35 tumors for each 

 of the four symbols, 2, B, K, and S, as the seventh unit. ) 



When a symbol for any particular organ-tissue type of tumor (units one through seven) has less 

 than seven units (e.g. , glandular tumors of the fundic stomach, S1A112--) and is incorporated into a 

 specific tumor symbol, Symbol is used as a unit or units between the final unit of the tumor- type 

 code designation and the eighth unit; for example, Carcinoma 303, S1A11201. (This is explained 

 again, in a slightly different way, in Division 8, below. ) Thus, in the case of any specific named 

 tumor, of a tumor type whose symbol is less than seven units, the seventh unit of the eight-unit total 

 symbol is always 0; this seventh unit symbol, 0, can be combined with eighth units in only 35 ways 

 for 35 specific tumors. This is due to the fact that numerical Symbol (= zone punch 0) can not be 

 combined on the IBM punched card with the other numerical symbols (2-9) to make corresponding 

 letter symbols, because this combination is reserved for those other numerical symbols when they 

 occur as seventh units. (Refer to the first paragraph of this division. ) However, it is suggested 

 that, in enlarging the Tumor Code, if there actually occurs a series of more than 35 specific tumors 

 with identical organ-tissue origins and with their seventh units being Symbol 0, it will be possible to 

 combine the with one of the other zone punches (written on the code sheet as * or *h to make 70 

 combinations for 70 more specific tumors. 



Even though specific tumor symbols may have Symbol as their seventh unit (or as any or all 

 of their second to seventh units), or though specific tumor symbols may have letter symbols as their 

 seventh units, neither Symbol nor any letter symbol in the seventh place can be interpreted as 

 representing that tumor type . When searching information files for all data on tumors of a given type, 

 therefore, the tumor list should be consulted for the symbol for that particular tumor type; that symbol 

 will not end in nor, if it has seven units, will its seventh unit be any symbol other than numerical, 

 1 through 9. 



36 



