Is this a bit odd/strange?

There's a guy at my high school who has cancer and has been having chemotherapy so had to retake the year but now he's well enough to come to school but wears a hat to cover his head. But strangely, I find him really attractive, but only since I found out he had cancer. I don't even know him personally so I feel pretty shallow. I even asked myself 'would you fancy him if he didn't have cancer?' and I realized the answer is no. Is this particularly unusual or has anyone else had a similar experience?