stagec {rpart} | R Documentation |
Stage C Prostate Cancer
Description
A set of 146 patients with stage C prostate cancer, from a study exploring the prognostic value of flow cytometry.
Usage
data(stagec)
Format
A data frame with 146 observations on the following 8 variables.
pgtime
Time to progression or last follow-up (years)
pgstat
1 = progression observed, 0 = censored
age
age in years
eet
early endocrine therapy, 1 = no, 2 = yes
g2
percent of cells in G2 phase, as found by flow cytometry
grade
grade of the tumor, Farrow system
gleason
grade of the tumor, Gleason system
ploidy
the ploidy status of the tumor, from flow cytometry. Values are ‘diploid’, ‘tetraploid’, and ‘aneuploid’
Details
A tumor is called diploid (normal complement of dividing cells) if the fraction of cells in G2 phase was determined to be 13% or less. Aneuploid cells have a measurable fraction with a chromosome count that is neither 24 nor 48, for these the G2 percent is difficult or impossible to measure.
Examples
require(survival)
rpart(Surv(pgtime, pgstat) ~ ., stagec)