白斑在 10 年内发生恶变的几率为 3%至 33%。[53]Waldron CA, Shafer WG. Leukoplakia revisited. A clinicopathologic study 3256 oral leukoplakias. Cancer. 1975;36:1386-1392.http://www.ncbi.nlm.nih.gov/pubmed/1175136?tool=bestpractice.com[54]Wright JM. Oral precancerous lesions and conditions. Semin Dermatol. 1994;13:125-131.http://www.ncbi.nlm.nih.gov/pubmed/8060824?tool=bestpractice.com[130]Sciubba JJ. Oral leukoplakia. Crit Rev Oral Biol Med. 1995;6:147-160.http://www.ncbi.nlm.nih.gov/pubmed/7548621?tool=bestpractice.com[131]Scully C, Cawson RA. Potentially malignant oral lesions. J Epidemiol Biostat. 1996;1:3-12.不同临床类型的白斑转化为癌的几率不同。此外,病变总尺寸与恶变几率有关,当病损面积超过 200 平方毫米时,其恶变的风险将会提高 5.4 倍。[123]Holmstrup P, Vedtofte P, Reibel J, et al. Long-term treatment outcome of oral premalignant lesions. Oral Oncol. 2006;42:461-474.http://www.ncbi.nlm.nih.gov/pubmed/16316774?tool=bestpractice.com疣状癌是一种进行性病变,复发率和 5 年生存率较高。[132]Sciubba JJ, Helman JI. Current management strategies for verrucous hyperkeratosis and verrucous carcinoma. Oral Maxillofac Surg Clin North Am. 2013;25:77-82.http://www.ncbi.nlm.nih.gov/pubmed/23399397?tool=bestpractice.com
尽管很多临床医生认为白斑的解剖学部位与其恶变几率有关,但是也有人不认同这一观点。此外,在选择总体治疗方案时,没必要对烟草相关性白斑和特发性白斑进行区分。[118]van der Waal I, Axell T. Oral leukoplakia: a proposal for uniform reporting. Oral Oncol. 2002;38:521-526.http://www.ncbi.nlm.nih.gov/pubmed/12167428?tool=bestpractice.com
大多数白斑,尤其是均质型白斑,
[Figure caption and citation for the preceding image starts]: 均质型白斑承蒙 James Sciubba 医生提供;准许使用 [Citation ends].恶变潜能低。发展成癌的白斑可能产生于一个癌前上皮区域,该区域由处在不同细胞遗传学变化阶段的角质形成细胞组成。[133]Feller L, Lemmer J. Oral leukoplakia as it relates to HPV infection: a review. Int J Dent. 2012;2012:540561.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3299253/http://www.ncbi.nlm.nih.gov/pubmed/22505902?tool=bestpractice.com