据估算AK进展为侵袭性鳞状细胞癌(SCC)的年风险大约在0.025%至16%之间。[124]Marks R, Rennie G, Selwood TS. Malignant transformation of solar keratoses to squamous cell carcinoma. Lancet. 1988;1:795-797.http://www.ncbi.nlm.nih.gov/pubmed/2895318?tool=bestpractice.com[125]Glogau RG. The risk of progression to invasive disease. J Am Acad Dermatol. 2000;42:23-24.http://www.ncbi.nlm.nih.gov/pubmed/10607353?tool=bestpractice.com
AK患者随访10年后,经估算其恶性转化的终生风险在6.1%至10.2%之间。
尽管据报道AK在12个月内发生自然消退的概率高达25.9%,但这其中有15%将来会复发。[2]Berman B, Bienstock L, Kuritzky L, et al. Primary Care Education Consortium; Texas Academy of Family Physicians. Actinic keratoses: sequelae and treatments. Recommendations from a consensus panel. J Fam Pract. 2006;55(suppl):1-8.http://www.ncbi.nlm.nih.gov/pubmed/16672155?tool=bestpractice.com[50]Quaedvlieg PJ, Tirsi E, Thissen MR, et al. Actinic keratosis: how to differentiate the good from the bad ones? Eur J Dermatol. 2006;16:335-339.http://www.ncbi.nlm.nih.gov/pubmed/16935787?tool=bestpractice.com[126]Marks R, Foley P, Goodman G, et al. Spontaneous remission of solar keratoses: the case for conservative management. Br J Dermatol. 1986;115:649-655.http://www.ncbi.nlm.nih.gov/pubmed/3801305?tool=bestpractice.com
误诊也会影响结果。一项研究表明临床诊断为AK的皮损实际上有36%是SCC,其中14%是原位SCC。[127]Suchniak JM, Baer S, Goldberg LH. High rate of malignant transformation in hyperkeratotic actinic keratoses. J Am Acad Dermatol. 1997;37:392-394.http://www.ncbi.nlm.nih.gov/pubmed/9308551?tool=bestpractice.com另一项研究中,通过资格认证的皮肤科医生临床诊断为AK的皮损中有4%实际上是SCC,有5%被当成是隐性的早期皮肤恶性肿瘤。[128]Ehrig T, Cockerell C, Piacquadio D, et al. Actinic keratoses and the incidence of occult squamous cell carcinoma: a clinical-histopathologic correlation. Dermatol Surg. 2006;32:1261-1265.http://www.ncbi.nlm.nih.gov/pubmed/17034376?tool=bestpractice.com
另外,一项研究表明所有SCC中有40%发生于之前外观正常的皮肤,有60%是由AK发展而来。[124]Marks R, Rennie G, Selwood TS. Malignant transformation of solar keratoses to squamous cell carcinoma. Lancet. 1988;1:795-797.http://www.ncbi.nlm.nih.gov/pubmed/2895318?tool=bestpractice.com
高危人群中的结果(如免疫力低下人群)
免疫力低下的人群中新发AK的风险更高(如器官移植患者),[129]Kinlen LJ, Sheil AG, Peto J, et al. Collaborative United Kingdom-Australasian study of cancer in patients treated with immunosuppressive drugs. Br Med J. 1979;2:1461-1466.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1597175/pdf/brmedj00103-0009.pdfhttp://www.ncbi.nlm.nih.gov/pubmed/393355?tool=bestpractice.com[130]Blohme I, Larko O. Skin lesions in renal transplant patients after 10-23 years of immunosuppressive therapy. Acta Derm Venereol. 1990;70:491-494.http://www.ncbi.nlm.nih.gov/pubmed/1981421?tool=bestpractice.com且该人群中 AK 恶性转化的发生率高。[131]Walder BK, Robertson MR, Jeremy D. Skin cancer and immunosuppression. Lancet. 1971;2:1282-1283.http://www.ncbi.nlm.nih.gov/pubmed/4143536?tool=bestpractice.com[132]Hardie IR, Strong RW, Hartley LC, et al. Skin cancer in Caucasian renal allograft recipients living in a subtropical climate. Surgery. 1980;87:177-183.http://www.ncbi.nlm.nih.gov/pubmed/6986671?tool=bestpractice.com
免疫抑制发生1年后皮肤肿瘤的累积发生率可升至7%,11年后可达到45%,20年后可达到79%。[133]Bouwes Bavinck JN, Hardie DR, et al. The risk of skin cancer in renal transplant recipients in Queensland, Australia. A follow-up study. Transplantation. 1996;61:715-721.http://www.ncbi.nlm.nih.gov/pubmed/8607173?tool=bestpractice.com
患有遗传性黑素缺乏的患者(如白化病)和DNA不稳定的患者(如着色性干皮病)更容易在早期发生AK,其中大于20岁的白化病患者中AK发生率可达到91%,着色性干皮病患者中可达到19%。
治疗效果
治疗方法通常都会导致短暂的不良反应,但同时有效率也会较高。[47]de Berker D, McGregor JM, Hughes BR; British Association of Dermatologists
Therapy Guidelines and Audit Subcommittee. Guidelines for the management of actinic keratoses. Br J Dermatol. 2007;156:222-230.http://www.bad.org.uk/library-media%5Cdocuments%5CActinic_keratoses_guidelines_2007.pdfhttp://www.ncbi.nlm.nih.gov/pubmed/17223860?tool=bestpractice.com
已经发现适当使用广谱防晒霜做好防护能够减少AK数目并且预防新皮损的产生。[43]Thompson SC, Jolley D, Marks R. Reduction of solar keratoses by regular sunscreen use. N Engl J Med. 1993;329:1147-1151.http://www.ncbi.nlm.nih.gov/pubmed/8377777?tool=bestpractice.com
多数治疗方法都能达到90%以上的治愈率,[134]Dinehart SM. The treatment of actinic keratoses. J Am Acad Dermatol. 2000;42:25-28.http://www.ncbi.nlm.nih.gov/pubmed/10607354?tool=bestpractice.com据报道冷冻手术能够达到99%的清除率。[135]Lubritz RR, Smolewski SA. Cryosurgery cure rate of actinic keratoses. J Am Acad Dermatol. 1982;7:631-632.http://www.ncbi.nlm.nih.gov/pubmed/7142470?tool=bestpractice.com
据报道皮损完全缓解、美容效果达到好至良好的比例占到94%至97%。[136]Thai KE, Fergin P, Freeman M, et al A prospective study of the use of cryosurgery for the treatment of actinic keratoses. Int J Dermatol. 2004;43:687-692.http://www.ncbi.nlm.nih.gov/pubmed/15357755?tool=bestpractice.com[137]Zouboulis CC, Rohrs H. Cryosurgical treatment of actinic keratoses and evidence-based review. Hautarzt. 2005;56:353-358.http://www.ncbi.nlm.nih.gov/pubmed/15580450?tool=bestpractice.com冷冻时间大于20秒的皮损可达到83%的完全缓解(或治愈)率。
刮除术单独应用或联合电干燥法应用均可达到较高的治愈率以及良好的美容效果。[134]Dinehart SM. The treatment of actinic keratoses. J Am Acad Dermatol. 2000;42:25-28.http://www.ncbi.nlm.nih.gov/pubmed/10607354?tool=bestpractice.com
浅表剥脱术总的有效率约在75%左右,复发率在25%至35%之间。[138]Stockfleth E, Kerl H; Guideline Subcommittee of the European Dermatology Forum. Guidelines for the management of actinic keratoses. Eur J Dermatol. 2006;16:599-606.http://www.ncbi.nlm.nih.gov/pubmed/17229598?tool=bestpractice.com