Diagnosis of mammary disorders calls for the exercise of considerable skill and experience. Often, only biopsy can decide the issue. Nevertheless, we believe that every effort should be made to evaluate the lesion prior to operation. A correct diagnosis, if it does nothing more, will at least enable the surgeon to plan his operation correctly. Here roentgenology has made a definite contribution.4 But what can be said of those cases in which clinical studies suggest carcinoma of the breast and no mass can be discovered? It is evident that more than plain clinical acumen is required, and it is in these cases that an x-ray examination by finding, localizing, and diagnosing the tumor can be of the greatest assistance.
In the last four years we have examined over 1000 cases of breast disorders, of which 175 were carcinomas. Among them were five in which the carcinoma, although suspected, could