The histology and nature of mixed tumours
Rowe, Robert Morison
The paper is based upon two cases which came under observation about the same time, whilst I was acting as House Surgeon to the Cumberland Infirmary, Carlisle.The cases occurred in two different situations in different individuals, the first cases connected with the kidney occurring in a woman of 55, the other connected with the coccyx in a foetus of 6 months.When one compares the constitution of the Coccygeal Tumour, as exemplified in the series of drawings, with the description of Teratoid Tumours and Teratomata, one is in doubt as to the class to which it may justly be assigned.The absence of higher differentiation of the tissues - for there are no organs or skin appen- dages present - inclines one to assign it to the class of Teratoids.On the other hand, one finds in the tumour a tissue which is ordinarily derivable only from the cephalic end of the body, viz: pigmented epithelium closely resembling Retinal Pigmented Epithelium (drawing No. 4).Were one able to say definitely that Retinal tissues are present, one must describe the tumour as a Teratoma, seeing that no Coccygeal Teratoid could contain a tissue proper to the cephalic end of the trunk.At the same time one must remember that the specimen was obtained from a foetus at the 6th. month of intra-uterine life so early that one is not justi- fied in assuming that the tumour had already attained its full development and its tissues their final stage of differentiation.In view of the theory of the common mode of origin of both Teratoid and Teratoma discussed above, one prefers to leave the question open, inclining, however, to the opinion that the tumour is in all probability a Coccygeal Teratoma.