Chapped Lips Can Be Considered As A Side Effect Of Chemotherapy?

I am a cancer patient being treated for rectal cancer. Last summer I went thru radiation concurrent with chemotherapy, both of which ended somewhere between the end of August and the middle of September. In October my rectum was removed and I was fitted with a colostomy. Since about mid-January I have gone back on chemo, three days per week, every other week, with my last treatment coming mid-April. My problem is that recently I have been suffering from what feels like chapped lips on the INSIDE of my lips. I have to say my oral hygiene hasn t been up to par due to my simply feeling crappy from the chemo. So, does the problem inside my lips sound like a result of the chemotherapy or could it be some sort of a periodontal disease caused by my intermittent brushing? — John in Sacramento