R help - Mar 2012 - Extended Survival Plot Lines

I've obtained a survival plot from the following code:

    s = Surv(outcome.[,1], outcome.[,2])
    survplot= (survfit(s ~ person.list[,1]))
    plot(survplot, mark.time = FALSE)

person.list is just a list of 15 people.

When I plot this, the lines on my plot all end at different time points. Is
there a way to extend all the lines to make them end at a certain time
point? (i.e outcome.[,1] is a time to event variable and I would like the
survival lines on the plot to extend out to say 5(years) )

http://r.789695.n4.nabble.com/file/n4457737/r_graph.jpeg 

Thanks, 
M

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> ...  Is there a way to extend all the lines to make them end at a
>  certain time point? (i.e outcome.[,1] is a time to event variable and
>  I would like thesurvival lines on the plot to extend out to say
>  5(years) )
No, there is no option in the plot.survival function to do this.  No one
has ever asked for this feature before (the function was written in
about 1988), so you are breaking new ground.  It is standard practice to
end a survival curve at the last observed time point; you are not likely
to convince me to add this as an option.

You can always plot the curves yourself:
   fit <- survfit(Surv(1:5, c(1,0,1,0,0)) ~1)
   plot(fit$time, fit$surv, type='s')  
   plot(c(0, fit$time), c(1, fit$surv), type='s') #Oops, add time 0 on

The key is using type='s' for a step function.  You can now tack on an
extra time point of your choice, 6 say, with c(0, fit$time, 6) for x and
c(1, fit$surv, min(fit$surv)) for y.  For multiple curves look more
closely at help("survfit.object")

Terry Therneau