1977 Volume 4 Issue 4 Pages 13-27
A latent factor, which will be called as “prognostic factor”, is extracted from nine explanatory variables observed mainly at the time of surgery from categorical principal component analysis, and it is shown that the factor has the appropriate meaning of prognosis measured on the postsurgical survival periods. Zero value on the prognostic factor is reflected to about five years on the postsurgical survival periods, and it is shown that positive values (or negative values) on the factor mean elongation more than (or shortening less than) about five years on the postsurgical survival periods. Further, this fact is confirmed by categorical canonical discriminant analysis of the same data. The effect of adjuvant chemotherapy is detected in the interaction with the serosal invasion, and elongation of about 34 months on the survival periods is obtained as the significant difference between the treated group with chemotherapy and the control group, at s1 category in serosal invasion.