PELLER* presented evidence in 1936 that the patient who had an epithelioma was less apt to develop a visceral cancer than the person with a normal skin. He based this conclusion on a study of the mortality statistics of England and Wales from 1921 to 1923. This so-called immunity persisted despite cure of the primary neoplasm. If this observation were true, it would suggest that epitheliomas could be produced by radiant, chemical, or mechanical means as a protection against malignant tumors with a poor prognosis. Peller went so far as to advocate this procedure, and Lancet published the suggestion. Being dissatisfied with the lukewarm reception to his idea, Peller has published a book claiming that cancer morbidity and mortality could be decreased by 90% by provoking early in life an epithelioma. One possible fallacy in this idea is to be found in Peller's concept that only 20% of