Background: During the last decade, increasing efforts have focused on HPV detection in self-obtained samples, to increase the overall proportion of patients participating in cervical cancer screening procedures.
Objectives: A clinical evaluation study of an optimized protocol for PCR detection of high-risk human papillomavirus (HPV) types in urine compared with cervical samples in consecutive women referred to the colposcopy clinic with abnormal cervical cytology.
Study design: Paired urine and cervical specimens were collected from 100 consecutive women referred to the colposcopy clinic with abnormal cervical cytology and normal urine parameters. In-house and a commercial PCR method for the detection of HPV types 16 and 18, and a commercial multiplex PCR for HPV types 6, 11, 16, 18, and 33 were performed. All HPV cervix-positive/urine-negative paired urine samples were spiked with serial dilutions of cell lines infected with HPV 16 or 18 to test the sensitivity of HPV detection in these urine samples.
Results: In all but two cases HPV type 16 was detected. In cancer cases, the urine/cervix HPV detection sensitivity was 88.8%; in cases with high-grade lesions it was 76.5%; and in cases with low-grade lesions it was 45.5%. In all concordant cases the same HPV type was detected in both samples. The urine/cervix HPV detection sensitivity was higher when urine samples contained two or more epithelial cells per field in urine microscopy. HPV detection in 9 cervix-positive but urine-negative urine samples spiked with serial dilutions of HPV-positive cell lines showed that in these cases urine PCR inhibitors did not affect PCR amplification.
Conclusions: A higher urine/cervix HPV detection sensitivity in cancer and high-grade lesions suggests that urine testing could be used to detect HPV mainly when these lesions are present.