[436] Age-Specific HPV, High-Risk HPV and HPV16/18 Rates and Follow-Up Histologic Diagnoses in Women with Atypical Squamous Cells of Undetermined Significance (ASC-US). A Study of 17,059 Cases from a Predominantly Low-Risk Screening Population.
Charanjeet Singh, Roberto G Gamez, Bharat Thyagarajan, Jana Holler, Evin H Gulbahce, Stefan E Pambuccian. University of Minnesota, Minneapolis
Background: ASC-US is the most frequent abnormal diagnosis made on Pap tests and the most frequent cytologic diagnosis leading to the diagnosis of clinically significant cervical precursor lesions (CIN 2/3).
The aim of this study was to review our experience with HPV reflex testing and genotyping and follow-up CIN2/3 diagnoses of women with ASC-US from a predominantly low-risk, suburban screening population
Design: All cases diagnosed as ASC-US according to the 2001 Bethesda System with a HPV test performed by PCR from 12/3/2003 to 6/30 2009 were entered into a spreadsheet together with the age of the patient, HPV type and follow-up biopsy diagnoses within 6 months. Any HPV+, high-risk HPV+ (HPV types included in the hc2 cocktail), HPV16/18+ and follow-up diagnoses of CIN2/3 were then compared.
Results:
| Age | <20 | 20-29 | 30-39 | 40-49 | 50-59 | >60 | Number of cases of ASC-US (% of total ASC-US) |
| Total ASC-US | 1182 | 5656 | 3702 | 3990 | 1784 | 745 | 17059 |
| Any HPV type (% of all ASC-US) | 720 (60.9%) | 3054 (54.0%) | 1303 (35.2%) | 798 (20.0%) | 427 (23.9%) | 196 (26.3%) | 6498 (38.1%) |
| HR-HPV (% of all ASC-US) | 377 (31.9%) | 1488 (26.3%) | 594 (16.1%) | 301 (7.5%) | 118 (6.6%) | 62 (8.3%) | 2940 (17.2%) |
| HR-HPV (% of all HPV+ASC-US) | 377 (52.4%) | 1488 (48.7%) | 594 (45.5%) | 301 (37.7%) | 118 (27.6%) | 62 (31.6%) | |
| HPV16/18 (% of all ASC-US) | 200 (16.9%) | 836 (14.8%) | 287 (7.8%) | 122 (3.1%) | 41 (2.3%) | 24 (3.2%) | 1510 (8.9%) |
| HPV 16/18 (% of all HPV+ASC-US) | 200 (27.7%) | 836 (27.3%) | 287 (22.0%) | 122 (15.2%) | 41 (9.6%) | 24 (12.24%) | |
| Biopsies (% biopsied) | 242 (20.4%) | 1391 (24.4%) | 760 (20.5%) | 564 (14.1%) | 268 (15.0%) | 93 (12.48%) | 3318 (19.45%) |
| CIN2/3 (% of all ASC-US) | 59(4.9%) | 242(4.2%) | 97(2.60%) | 44(1.1%) | 11(0.6%) | 3 (0.4%) | 456 (2.7%) |
| CIN 2/3 (% of all biopsies) | 59(24.4%) | 242(17.4%) | 97(12.8%) | 44(7.8%) | 11(4.1%) | 3 (3.2%) | |
| Risk of CIN2/3 in HPV16/18+ ASC-US | 33 (42.9%) | 129 (31.5%) | 40 (26.3%) | 13 (21.3%) | 3 (12.0%) | 1 (12.5%) | |
| Odds of CIN2/3 HPV16/18+ASC-US vs. non-16/18-HRHPV+ASC-US | 4.0 | 3.5 | 3.4 | 4.1 | 4.0 | 4.1 |