How To Treat Large Lump On Knee In A Diabetic Patient?

Hi, I have a large lump on my knee which has been there for a number of years, I have spoke to my doctor about this on numerous occasions & he informed me that it is housewives knee, i have come to bed tonight to see on my knee what looked like a small pimple, i sort of squeezed it at which point lots of white thick stuff has come out.I am a type 1 diabetic also.