Lying about cancer ?

After always having a sore throat and having to go to the doctors one day my boyfriend told me he got diagnosed with throat cancer.

I was in shock of course and he seemed really devastated. When it has come to appointments he always has his family come with him and not me because they apparently don’t want him to tell anyone...not even me.

I have never seen a official doctors letter about his diagnoses. But after a history of lying I wanted to know if he was lying. Whenever I say “is your cancer real...” he would get defensive and go “only a sick person would lie about such a thing” which is correct. I don’t mean to be doubtful or insensitive but I just want to know the truth...nor did I want to invade his privacy but I called his dad asking about his cancer and he sounded so confused “what cancer” “I didn’t know???” “When did he tell you this??” ..So when I called my boyfriend telling him I know he doesn’t have it, he flipped it on me and said “your so weird, why would you call him. He denied it because he told me not to tell anyone” I didn’t even bother arguing back....one day he told me the hospital called him in for a blood test. when he came home, he didn’t have a plaster...he said they didn’t give him one..?? Wait huh?? I’m nosey but I really want to know the TRUTHHHHHH. the only evidence I have is word of mouth. Only his mouth at that. It’s only because of a lying past I’m not really convinced. but wait I forgot to mention. On the 27th of dec 2017 he told me he starts treatment on the 11th of January 2018. Funny enough...he did not attend this appointment. I said “why didn’t you go?” He said “I had probation, don’t you think probation is abit more important?” I said “...no” as I’m sure your probation officer has your medical notes and would be able to reschedule???? It’s just not adding up. 2+2=4 but he’s making me seem like I’m paranoid and getting 103. Does anyone else think he is lying ...???