  We discuss the sharp interface limit of a diffuse interface model for a
coupled Cahn-Hilliard--Darcy system that models tumor growth when a certain
parameter $\varepsilon>0$, related to the interface thickness, tends to zero.
In particular, we prove that weak solutions to the related initial boundary
value problem tend to varifold solutions of a corresponding sharp interface
model when $\varepsilon$ goes to zero.

Analysis of PDEs