His feet are turning blue?

Hi
We got news last week that although hubby has a new growth, it hasn't done anything since the last scan a month ago so he will stay on temodar for another 2 months before the next scan. Hubby was diagnosed with GBM in March 09. Over the weekend, he has been complaining that his feet and legs are swollen. Today they appear blueish. He is on Temodar for chemo and dilantin and tegretol for seizures. Could this be due to blood clots? Anyone else experience this? We have been in and out of hospital so often recently that he has refused to even see the GP. I am not sure if I should persist and get him an appointment anyway?