For larger flat warts, surgery may be necessary to remove the lesions. A famous surgical option would be that of laser. Although laser surgery is expensive, it has proven to be effective. The warts are physically burned off with the laser treatment. Another alternative treatment would be cauterization. In this procedure, the affected tissue is destroyed with a hot instrument.
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 dermatologist. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.