Findings and Challenges in Replacing Traditional Uterine Cervical Cancer Diagnosis with Molecular Tools in Private Gynecological Practice in Mexico.

We have been encouraging practicing gynecologists to adopt molecular diagnostics tests, PCR, and cancer biomarkers, as alternatives enabled by these platforms, to traditional Papanicolaou and colposcopy tests, respectively. An aliquot of liquid-based cytology was used for the molecular test [high-risk HPV types, (HR HPV)], another for the PAP test, and one more for p16/Ki67 dual-stain cytology. A total of 4499 laboratory samples were evaluated, and we found that 25.1% of low-grade samples and 47.9% of high-grade samples after PAP testing had a negative HR HPV-PCR result. In those cases, reported as Pap-negative, 22.1% had a positive HR HPV-PCR result. Dual staining with p16/Ki67 biomarkers in samples was positive for HR HPV, and 31.7% were also positive for these markers. Out of the PCR results that were positive for any of these HR HPV subtypes, n 68.3%, we did not find evidence for the presence of cancerous cells, highlighting the importance of performing dual staining with p16/Ki67 after PCR to avoid unnecessary colposcopies. The encountered challenges are a deep-rooted social reluctance in Mexico to abandon traditional Pap smears and the opinion of many specialists. Therefore, we still believe that colposcopy continues to be a preferred procedure over the dual-staining protocol.

A positive HPV test with positive p16/Ki-67 double staining in self-sampled vaginal material is an accurate tool to detect women at risk for cervical cancer.

BACKGROUND: The development of efficient strategies for managing high-risk human papillomavirus (HR-HPV)-positive women is a major challenge when human papillomavirus-based primary screening is being performed. The objectives of this study were to evaluate the comparative effectiveness of HR-HPV testing based on self-collection (SC) and HR-HPV testing based on collection by a health professional (HP) and to assess the potential usefulness of HR-HPV testing combined with testing with the biomarkers p16/Ki-67, α-mannosidase, and superoxide dismutase 2 (SOD2). METHODS: This was a cross-sectional study of 232 women admitted for colposcopy because of an abnormal Papanicolaou smear. The collected material underwent liquid-based cytology, HR-HPV detection, and immunocytochemical testing (p16/Ki-67, α-mannosidase, and SOD2). The gold standard was the histopathological result; the positive reference was CIN2+. RESULTS: The overall accuracy of HR-HPV testing was 76.6%; the results for the SC group (78.1%) and the HP group (75.2%) were similar. The positive predictive values (HP, 76.5%; SC, 80.0%), the negative predictive values (HP, 66.7%; SC, 64.3%), the positive likelihood values (HP, 1.35; SC, 1.36), and the negative likelihood values (HP, 0.21; SC, 0.19) were also similar. p16/Ki-67 showed higher sensitivity than the other 2 biomarkers: 78.1% versus 45.8% for α-mannosidase and 44.5% for SOD2. The specificities of the biomarkers were equivalent: 71.4% for p16/Ki-67, 77.8% for α-mannosidase, and 71.2% for SOD2. In the HP group, accuracy also leaned more heavily toward the final score (using α-mannosidase and SOD2) without statistical significance (80.8% vs 77.9%). The contrast with the SC group yielded the same level of accuracy. CONCLUSIONS: SC, when associated with testing with biomarkers, is as accurate as collection by HPs in the detection of women at risk for cervical cancer.

Association of p16 and Ki-67 with Risk of Recurrence in Previously Treated Cervical High-Grade Squamous Intraepithelial Lesions.

OBJECTIVE: Our main objective was to assess the association between the markers p16 and Ki-67 and recurrence of disease in patients previously treated for cervical high-grade squamous intraepithelial lesion (HSIL). DESIGN: This is a case-control study at the National Cancer Institute conducted between 2005 and 2015. Of the patients with a pathologically confirmed diagnosis of HSIL, 107 cases were selected. They were divided into 2 groups: 28 cases with recurrence after treatment and a control group of 79 patients without recurrence. We identified clinical, pathological, and treatment variables. METHODS: Two experienced pathologists performed immunohistochemical analysis of biomarkers; they agreed on their interpretation, and we calculated the odds ratios (ORs) associated with recurrence. For group comparisons, we used the Wilcoxon signed-rank, χ2, or Fisher's exact test, depending on the type of variable. We conducted logistic regression models to estimate ORs and determine the factors associated with recurrence. The recurrence-free period was defined as the time frame between conization and either recurrence of disease or the last date the patient was seen. We used Kaplan-Meier plots to visualize survival curves and log-rank tests to compare the curves. We established a p value <0.05 as statistically significant. RESULTS: After pathologists performed immunohistochemical analysis, they achieved an agreement level of 83.7% for p16 and 60% for Ki-67. We did not find an association between recurrence and either p16 expression (p = 0.69) or the percentage of Ki-67 expression (p = 0.71). The recurrence-free period analysis did not reveal a difference in p16 expression (p = 0.57) nor in the percentage of Ki-67 expression in the 3-tiered scale (p = 0.56). LIMITATIONS: Our main limitation was a reduced sample size. CONCLUSION: We found no association between p16 and Ki-67 positivity and the risk of recurrence in previously treated HSIL.

Adjunctive testing by cytology, p16/Ki-67 dual-stained cytology or HPV16/18 E6 oncoprotein for the management of HPV16/18 screen-positive women.

High-risk human papillomavirus type 16/18 (HPV16/18) genotyping is unable to accurately discriminate nonprogressive infections from those that will progress to cervical cancer. Our study aimed to assesses if additional testing either with liquid-based cytology (LBC) or the putative progression markers p16/Ki-67 and HPV16/18 E6 oncoprotein (E6) can improve the efficiency of HPV16/18 genotyping for triaging high-risk HPV (hrHPV)-positive women through better cancer risk stratification. Women attending colposcopy after positive HPV16/18 genotyping results within the Forwarding Research for Improved Detection and Access for Cervical Cancer Screening and Triage (FRIDA) hrHPV-based screening study in Tlaxcala, Mexico, underwent further testing with LBC, p16/Ki-67 dual-stained (DS) cytology and E6. We calculated measures of test performance for detecting histologically confirmed cervical intraepithelial neoplasia grade 2 or higher (CIN2+) and grade 3 or higher (CIN3+). A number of 475 (64.3%) of 739 HPV16/18-positive women had complete results for all tests. Triage positivity rates were 14.1%, 18.5% and 24.4%, for LBC, E6 and DS, respectively. Compared with LBC, DS had higher sensitivity (24.4% vs 60.0%) although lower specificity (87.0% vs 79.3%) for CIN3+ (P < .001), whereas E6 had a sensitivity of 37.8% and a specificity of 83.5%. No invasive cancer was missed by DS or E6, but 75% were in normal cytology. DS test was associated with nearly 75% reduction of colposcopy referrals compared with the direct referral of all HPV16/18-positive women, giving the least number of colposcopies (n = 4.3) per CIN3+ detected. We show that adjunctive testing of HPV16/18-positive women with DS may greatly reduce unnecessary colposcopy referrals within HPV-based screening employing HPV16/18 genotyping while retaining acceptable sensitivity for CIN2+ and CIN3+.