p16/Ki-67 dual staining in cervico-vaginal cytology: Correlation with histology, Human Papillomavirus detection and genotyping in women undergoing colposcopy
ABSTRACT To evaluate the CINtec PLUS assay (mtm laboratories), a new immunocytochemical method for the simultaneous detection of p16(INK4a) and Ki-67, in liquid-based cervico-vaginal cytology, investigating the association of the dual staining with HPV infection and genotyping as well as cytological and histological abnormalities.
140 women with a cervico-vaginal sample obtained immediately before the colposcopy were enrolled. This cytological sample was used for HPV testing with the Linear Array HPV Genotyping Test, the dual staining with the CINtec PLUS kit and the morphology assessment.
Cytology results were 38 NILM, 16 ASC-US, 32L-SIL, 54H-SIL or worse. 113 patients also had a colposcopy-guided biopsy, classified as 14 negative, 35 CIN1, 24 CIN2, 37 CIN3, 3 invasive SCC. A strong association between p16/Ki-67 and HR-HPV infection was found (COR=6.86, 95% CI: 1.84-31.14). Importantly, the association between p16/Ki-67 positivity and HPV16 and/or 18 infection was 2-fold stronger compared to that with the infection by other HR-HPV types (COR=9.92, 95% CI: 2.39-47.77 vs COR=4.20, 95% CI: 0.99-20.87). In addition, p16/Ki-67 positivity rate significantly increased with the severity of the cytological and histological abnormalities (p<0.05 in both cases). p16/Ki-67 positivity resulted strongly associated with a CIN2+ diagnosis (COR=10.86 95% CI: 4.16-29.12).
This preliminary study evidenced that p16/Ki-67 immunostaining might have a relevant clinical role, since the dual staining was significantly associated with HR-HPV infection, particularly with HPV 16 and 18, and the increasing grade of the cervical lesions, the positivity for this biomarker being strongly related to the presence of a CIN2+ lesion.
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ABSTRACT: Ki-67 expression is an important tool for distinguishing between malignant and benign tumors. It usually shows the nuclear staining. However, the cell membrane staining of MIB-1, which is one of the clones of Ki-67, in the hyalinizing trabecular adenoma of the thyroid gland and other tumors had also been reported. In our practice, we found that the 7B11 antibody could be immunoreactived with the adipose tissues inside or around tumors in the membrane. Thus, in this study, we determined if Ki-67 expression would be useful in recognizing the lipoblasts and adipocytes. The five clones of the Ki-67 antibody, namely, 7B11, K-2, SP5, MIB-1, and SP6 were selected. The adipocytes showed strong 7B11 staining in the cell membrane. The brown fat cells were strongly immunoreactive with 7B11 in the arachnoid layer of the cytoplasm. The adipocytes and brown fat cells showed positive, albeit weaker K-2 staining in the cell membrane and cytoplasm, respectively, compared to 7B11. The adipose tissues and brown fat cells were non-reactive to clones SP5, MIB-1, and SP6. All adipocytes in the lipomas, angiolipomas, uterine lipoleiomyomas, and angioleiomyolipomas showed diffusedly positive 7B11 and K-2 staining in the cell membrane, with stronger immunoreactivity to 7B11 compared with K-2. All hibernomas showed diffusedly cytoplasmic arachnoid staining of 7B11, but only focal to K-2. The lipoblasts in adipocytic tumors also showed positive 7B11 and K-2 staining; however, nearly all of the vacuolated lipoblasts showed strong 7B11 staining, only focal vacuolated lipoblasts in the adipocytic tumors were immunoreactive to K-2 positivity. All other components of the adipocytic tumors were non-reactive to 7B11, K-2, SP5, MIB-1, and SP6 in the cell membrane and cytoplasm. Our results showed that the 7B11 could well help to identify the lipoblasts, which would be useful to diagnose the malignant adipocytic tumors.International journal of clinical and experimental pathology 01/2014; 7(12):8899-904. · 1.78 Impact Factor
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ABSTRACT: This study compared the performance of p16/Ki67 dual-staining and human papillomavirus (HPV) testing in women referred to colposcopy and sought to determine the usefulness of a morphological evaluation of the double-stained cells. This prospective study included 1123 women (mean age, 35.8 ± 10.9 years) referred to colposcopy from October 2009 to November 2012 due to positive HPV testing or abnormal cytology results (atypical squamous cells of unknown significance, or worse abnormalities). Liquid-based cytology specimens (PreservCyt, Hologic) were used for HPV detection (Hybrid Capture 2 [HC2]; Qiagen) and p16/Ki67 dual-staining (CINtec Plus; Roche-mtm Laboratories). All women underwent histological study. After completion of the study, 18 patients were classified as having cervical cancer (CC), 378 had a high-grade squamous intraepithelial lesion (HSIL), 304 had a low-grade squamous intraepithelial lesion, and 423 were negative. The sensitivity and specificity of p16/Ki67 dual-staining for HSIL/CC were 90.9% (95% confidence interval [CI] = 87.9-93.9) and 72.1 (95% CI = 68.7-75.4), respectively. For HC2, the figures were, respectively, 96.0% (95% CI = 93.9-98.0) and 41.4 (95% CI = 37.7-45.0). The values were high both in women < 30 and ≥ 30 years old (86.9% and 63.3% versus 92.3% and 77.8%, respectively). The addition of a morphological evaluation of the dual-stain-positive cells with establishment of HSIL features as the threshold for a positive reaction increased the specificity (93.5%) but decreased the sensitivity (84.1%). Use of the molecular markers p16 and Ki67 has higher specificity than HC2 tests for HSIL or CC, which may support p16/Ki67 dual-staining use in the triage of patients referred for abnormal screening results. Morphological evaluation of p16/Ki67-positive cells may have some benefits in women younger than 30 years or with low-grade squamous intraepithelial lesion.Cancer Cytopathology 03/2014; 122(3):227-35. DOI:10.1002/cncy.21366 · 4.43 Impact Factor
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ABSTRACT: p16(INK4a) immunohistochemistry has revealed a high rate of positivity in cervical intraepithelial neoplasia grade 2 (CIN2) and more severe conditions (CIN2+). The Lower Anogenital Squamous Terminology Standardization project proposed p16(INK4a) immunohistochemistry as an ancillary test for CIN. Immunocytochemistry involving dual staining for p16(INK4a) and Ki-67 in the triage of atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions (LSIL) is reported to be useful in the identification of CIN2+. However, it is unclear whether p16(INK4a)/Ki-67 immunocytochemistry is of practical relevance for the triage of ASCUS and LSIL in the Japanese screening system. From 427 women fulfilling the eligibility criteria, 188 ASCUS and 239 LSIL specimens were analyzed. The accuracy of p16(INK4a)/Ki-67 immunocytochemistry and genotyping of high-risk human papillomaviruses (HPVs) in detecting CIN2+ were compared. p16(INK4a)/Ki-67 immunocytochemistry was positive in 33.5 % (63/188) of ASCUS, and 36.8 % (88/239) of LSIL specimens. The sensitivity and specificity of p16(INK4a)/Ki-67 immunocytochemistry was 87.3 % (95 % confidence interval 78.0-93.8 %) and 76.4 % (71.6-80.8 %), respectively. The positive and negative predictive values were 45.7 % (37.6-54.0 %) and 96.4 % (93.4-98.3 %), respectively; positive and negative likelihood ratios were 3.71 and 0.17, respectively. Using the McNemar test, p16(INK4a)/Ki-67 immunocytochemistry showed equivalent sensitivity but higher specificity than the HPV genotyping test CONCLUSIONS: Compared with high-risk HPV genotyping, p16(INK4a)/Ki-67 immunocytochemistry was a more accurate triage test for identifying CIN2+ in ASCUS and LSIL specimens.International Journal of Clinical Oncology 04/2014; 20(1). DOI:10.1007/s10147-014-0688-0 · 2.17 Impact Factor