Virus del Papiloma Humano (HPV) y lesiones displásticas del cuello uterinoestudio epidemiológico tras tratamiento quirúrgico

Abstract

The aim of this study was to evaluate the progression, histopathological characteristics and the genotype-specific prevalence of Human Papilloma Virus (HPV) in women that underwent cervical conisation (LEEP) at the Gynaecologist Service of Leon University Hospital, Spain, between 1/1/1999 and 31/12/2009. The study population comprised 315 women that met the inclusion criteria, high-grade squamous intraepithelial lesion (HSIL) diagnosis and/or discrepancies between cytology and biopsy results. Data from clinical records of mentioned patients was statistically analysed, including: age, previous gynaecological history, smoking habits, methods of contraception, immunity state, number of previous vaginal smears, genotype of HPV, cytology, biopsy and colposcopy results. In addition, evaluation of cone biopsy: diagnosis, location and size of the lesions and follow-up with cytology and/or ADN test as well as special circumstances such as pregnancy and multicentric lesions of the lower genital tract were also assessed. Patients ranged in age from 30 to 77 years with a mean of 36,8 years. Most women were between 31 and 40 years (40,3 %), followed by 41-50 (27,0 %) and 20-30 years (26,9%). The vast majority of cases were treated with cervical conisation after HSIL diagnosis. Positive diagnosis was made by cytology and/or biopsy in 79.4% cases. No significant association was found among cone-biopsy and pregnancy, abortions, smoking habits, contraception measures or immune system state. Sixty percent of cases presented with a positive HPV-DNA test, of which 34,6% showed multiple type infections. Infection by AR genotype was demonstrated in 98,4% cases, of which 34.6% evidenced multiple type infections. The most frequently encountered genotypes of HPV in our study population were; 16 (61,1 %), 31 (9 %), 58 (4,8 %) 33 (4,3%) y 18 (3,2%). The colposcopy technique was able to identify major changes at the cervix in 32,4% cases (34,4 % HSIL and 50,0 % epidermoid carcinoma) and malignant changes in 2,9% cases (2,4 % HSIL and 16,7 % epidermoid carcinoma). Moreover, colposcopy was also useful detecting positive surgical margins in 20 % cases, in which endocervical margin was most commonly affected. X: SUMMARY 360 Follow up post-conisation revealed an abnormal cytology in 3,5 % cases, positive HPV-DNA test in 7,3 % cases and both abnormal tests in 3,8 %. No significant association between margins and positive HPV-DNA test was found. Recurrence of disease was detected in 10.6% cases (32/301), of which surgical margins were commonly affected (59,4%), particularly endocervical margin (18,8 %). In 31, 3% cases of recurrence, abnormal cytology and/or HPV-DNA test was observed at 6 and/or 12-month postconisation, with only 9.4 % cases positive for HPV-DNA test. Fifty-six percent of patients underwent posterior-reconisation and hysterectomy and 21,9 % hysterectomy. HSIL diagnosis was confirmed in all the patients that sustained reconisation or hysterectomy. However positive diagnosis was not achieved in patients that were treated with both surgical techniques, as the lesion had been surgically excised in its totality during the reconisation process. Multicentric lesions of the lower genital tract was found in one case out of the 315 examined. In this case a VAIN diagnosis of the vaginal vault 3 years postconisation was confirmed. Although diathermia handle conisation has a good success rate for the treatment of preneoplastic cervical lesion, there is a percentage of cases that will present recurrence regardless of the surgical margins achieved by the cone biopsy. In order to avoid this risk the patients will follow and standardised protocol, including cytology and/or HPV-DNA test. The results of these tests will determine the subsequent complementary treatment and/or specific follow-up. Although the sensitivity and specificity of both tests are elevated, a long term follow up is necessary due to the increased risk of these patients compared to the general population. Furthermore, this long term follow up will also aid to detect persistent infections or reinfections by different viral genotypes. It is important to perform prevalence studies of HPV genotypes in different areas of the country to understand the mechanisms of infection, oncogenesis and vaccination effectiveness against HPV in female population. Our study revealed that genotype 16, 31, 18, 58 and 33 were the most common in our study population, in contrast to other studies conducted in Spain.