Rash on scalp

My husband, Steve, just finished his fourth treatment of Folfiri with Avastin. After the third treatment, red pumps developed on his scalp. They look like scabby pimples. They don't bother him. Not itchy. At chemo last Wed the nurse paged the onc. Steve's onc did not see the bumps but based on the nurses description she does not think it's chemo related. Last time he developed a rash on his back, but it seems fine so far. I tend to think it is related to the chemo just because of the timing. He has never had any other scalp issues. The appearance of it seems to bother him as his hair is falling out and it's quite noticeable. Has anyone experienced a similar problem?

Thanks

Chelsea