Diabetic. Lost Weight With Yellow Skin. Tumor On Liver. Help?

Hi my dad has gone very yellow, infact he s the colour of a cigaret but and he s lost about 2 stone within 5 weeks, he has only just told me, he s olso a diabetic, he has said he s waiting on a scan and it should just be down to a tumour on the liver which can be drained easily or he s gual bladdor which can easily be removed, dose this sound right to you? Or could it be something else, I m so scared it could be cancer! He is olso a recovered alcoholic but has been dry for about 4 years now