Evaluation of the efficacy and safety of 5-aminolevulinic acid-mediated photodynamic therapy in women with high-risk HPV persistent infection after cervical conization

Abstract

Objective: To evaluate the efficacy and safety of photodynamic therapy (PDT) in women with high-risk human papillomavirus (hr-HPV) persistent infection after cervical conization, including loop electrosurgical excision procedure (LEEP) and cold knife conization (CKC).

Materials and methods: The clinicopathological and follow-up data of 76 women with hr-HPV persistent infection after cervical conization (54 cases with LEEP and 22 cases with CKC) were collected. All the women in this group met these criteria: postoperative pathological diagnosis of LEEP/CKC showed high grade squamous intraepithelial lesions (HSIL) with negative incisal margin, hr-HPV persistent infection after LEEP/CKC ≥ 1 year, colposcopy and histopathology showed no intraepithelial lesions before PDT, and 5-aminolaevulinic acid (5-ALA) as photosensitizer treating for 6 times with an interval of 7-10 days. The above patients were followed up 6 months and 12 months after PDT, and the follow-up contents included Roche Cobas HPV classification test, cytology, colposcopy, and pathological examinations. HPV negative conversion rate is an index to evaluate the efficacy of PDT. In addition, we also assessed the safety of PDT.

Results: Six months after PDT, the overall HPV clearance rate was 59.21% (45/76). The HPV negative conversion rates in patients ≤ 50 years old group and > 50 years old group were 68.52% (37/54) and 36.36% (8/22), respectively (P=0.009). But there was no significant difference in HPV clearance rate between the HPV16/18 infection group and other hr-HPV infection group (P=0.3326). 12 months after PDT, 1 case underwent hysterectomy because of progression to HSIL, and 7 cases lost follow-up. The overall HPV clearance rate was 88.24% (60/68). The negative conversion rates of HPV16/18 and other hr-HPV infection groups were 76.00% (19/25) and 95.35% (41/43), respectively (P=0.0458). However, the HPV negative conversion rate was not correlated with the patient's age (P=0.2383). The adverse reactions after PDT were mild, mainly manifested as increased vaginal secretions or burning/tingling.

Conclusions: Photodynamic therapy could be an effective treatment for patients with hr-HPV persistent infection after cervical conization and it could promote the negative conversion of hr-HPV and prevent the recurrence progression of cervical intraepithelial neoplasia (CIN) after LEEP/CKC.

Keywords: Adverse pregnancy outcome; LEEP/CKC; Persistent HPV infection; Photodynamic therapy.