Cryotherapy for oral precancers and cancers.

Previous studies have used cryotherapy for the treatment of oral precancers including oral leukoplakia (OL) and oral verrucous hyperplasia (OVH) as well as oral cancers including oral verrucous carcinoma (OVC) and oral squamous cell carcinoma (OSCC). Cryotherapy is a method that locally destroys lesional tissues by freezing in situ. It can be carried out by either an "open" or a "closed" system. Lesional tissues are destroyed mainly through disruption of cell membrane, cellular dehydration, enzyme and protein damage, cell swelling and rupture, thermal shock injury to cells, damage to vasculature, and immune-mediated cytotoxicity. Cryotherapy is used frequently for the treatment of OL lesions with promising results. It can also be used to treat OVH and OVC lesions. Because OVH and OVC lesions are usually fungating and bulky, a combination therapy of shave excision and cryotherapy is needed to achieve a complete regression of the lesion. OSCCs have also been treated by cryotherapy. However, cryotherapy is not the main-stream treatment modality for OSCCs. Cryotherapy seems suitable for treatment of thin or relatively thick plaque-typed lesions such as OL lesions. By careful selection of patients, cryotherapy is a simple, safe, easy, conservative, and acceptable treatment modality for certain benign oral lesions and oral precancers.