Hello,
This blue patch can be due to venous lake or oral melanotic macule. Venous lake is a dark blue compressible papule caused by dilation of venules and lips are very commonly affected. Treatment is by cryosurgery, electrosurgery, sclerotherapy, excision and laser treatment. Please discuss these options with a cosmetologist in detail.
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.
http://i1225.photobucket.com/albums/ee390/4geeez/IMAG0082.jpg