A randomized clinical comparative study of cryotherapy plus photodynamic therapy vs. cryotherapy in the treatment of multiple condylomata acuminata

BACKGROUND: Cryotherapy cannot destroy subclinical human papillomavirus-infected cells of condylomata acuminata (CA). The topical application of aminolevulinic acid (ALA) results in a shallow penetration depth in CA lesions (1). OBJECTIVES: To compare the efficacy and safety of cryotherapy plus ALA-photodynamic therapy (PDT) with cryotherapy in the treatment of multiple CA. METHODS: Eighty patients with multiple CA received cryotherapy plus ALA-PDT (n=40) or cryotherapy plus placebo-PDT (n=40). After cryotherapy, a 20% ALA or a placebo solution was applied to the CA area 3 h before illumination with red light (635 nm, 100 mW/cm(2) , 100 J/cm2). The treatment was repeated 7 days after the first treatment if the lesions were not completely resolved. The complete response rate, recurrence rate and adverse effects in the two groups were analyzed. RESULTS: After two treatments, the complete response rates in the combined group (cryotherapy plus ALA-PDT) and cryotherapy group were 32.4% (36/111) and 32.6% (43/132) in the anal area (P>0.05), 100% (32/32) and 54.5% (18/33) in the urethral meatus (P<0.05), and 94.2% (129/137) and 50.5% (56/111) in the external genitals (P<0.05), respectively. The recurrence rates in the combined group and cryotherapy group were 24.3% (27/111) and 31.1% (41/132) in the anal area (P>0.05), 9.4% (3/32) and 39.4% (13/33) in the urethral meatus (P<0.05), and 3.6% (5/137) and 31.5% (35/111) in the external genitals (P<0.05), respectively. The adverse effects in each group included mild to moderate pain, edema, erosion and hypopigmentation, without any infection, ulcers, scarring or urethral malformations. CONCLUSION: Cryotherapy plus ALA-PDT is a more effective regimen for the treatment of multiple CA compared with cryotherapy alone.