It needs to be checked...either by your DDS or family MD.
Hello,
It can be a hyperkeratotic papule which can be due to actinic cheilitis, leukoplakia or some benign or malignant growth on the lips. Leukoplakia is a white lesion that can't be removed simply by rubbing the mucosal surface. It may occur in response to chronic irritation from dentures or from tobacco use or pipe smoking, or it may represent dysplasia.
I agree with your doctor because examination is required to confirm the diagnosis.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.