2q8 Tumors o£ the Testis 



this distinction is not always clear-cut. There are transitional stages. The 

 tumor may seem to be solidly composed of fully differentiated adult cells 

 until diligent search through serial sections discloses undifferentiated pri- 

 mordial cells or scattered gioups of such cells which may be in different stages 

 of transition. The most primitive form of cell is the one by which the tumor 

 should be classified. Chorion-like cells are the most premature. Whether this 

 distinguishing cell occurs in a monocellular or in a mixed type of tumor is 

 unimportant. In either case the growth is a chorionepithelioma. The recog- 

 nition of the embryonal or mature character of a tumor with transitional 

 phases in either direction has considerable clinical value as can be demon- 

 strated by correlation of the pathologic, clinical, and biochemical facts. 



Pathology 



Ewing grouped all tumors of the testis in four ways: 



1. Adult embryoma or teratoma (benign) 



2. Embryonal teratoid or mixed tumor (malignant) 



3. Embryonal malignant tumor (embryonal carcinoma) 



4. Miscellaneous (rare) 



a. Adenoma 

 h. Fibroma 



c. Myoma 



d. Sarcoma 



e. Interstitial-cell tumor 

 /. Lymphosarcoma 



g. Adult multicystic adenocarcinoma (arising from adult cells of semi- 

 niferous tubules) 



The tumors which can be classified under groups 1 and 4 are very rare, so 

 rare indeed that, clinically, only groups 2 and 3 need be considered in the 

 present correlation of facts. Disregard of the distinction between monocellular 

 and mixed-cell tumors unites these two groups so that, except for the fore- 

 going very rare neoplasms mentioned in groups 1 and 4, there is only one 

 testicular tumor. This tumor probably arises from a totipotent cell and may 

 undergo a gieat variety of transitions, the nature of which can be inferred 

 by the microscopic picture presented at the particular phase present when 

 the tumor is examined. If the growth is allowed to develop further, however, 

 subsequent examination may disclose an entirely different picture. For ex- 

 ample, the primary growth found in the testis after castration may show a 

 pure embryonal carcinoma but the metastases examined months later may 

 disclose chorionepithelioma. 



Suspecting the importance of cellular maturity as the basis of classification 

 of testicular tumors. Dr. Jesse L. Carr, who has reviewed all our pathological 

 material, attempted such a differentiation several years ago. Careful correla- 

 tion of pathological with clinical and biochemical facts has evolved the fol- 

 lowing division, the principal distinction of which is recognition of cellular 



