Key points are not available for this paper at this time.
From the Department of Pathology, Memorial Hospital for Cancer and Allied Diseases, New York, New York 10021 *Present Address: Department of Pathology, New Jersey College of Medicine and Dentistry, Newark, N. J. **Present Address: Head, Epidemiologic Pathology Unit, National Cancer Institute–NIH, Bethesda, Maryland 20014.
Huvos et al. (1971) studied this question.