How to perform a specific Coxph analysis using a continuous variable?

Question

[David52]

Hello - I am new to survival analysis and would like to perform category specific Coxph analysis on a continuous gene expression data. For instance, I have OS data and I would like to see if patients overexpressing T cells in specific tumor cell subtypes (Subtype 2) have better chances of survival than compared to all other subtypes (e.g. Subtype 1, Subtype 3, and Subtype 4).

Here is what my sample code in R looks like:

library(survival) # Load survival curve package
library(survminer)

fit <- coxph(Surv(OS,OS_event) ~ Subtype + T_cells, data = Final_Dataset)
summary(fit)
ggforest(fit, data=Final_Dataset)

I would greatly appreciate any help in this case!

[Kevin Blighe]

Hello, sorry, without showing a sample of your data, there's not much on which we can comment. What is T_cells, specifically? It seems that you may in fact want an interaction between Subtype and T_cells