Atypical immature metaplastic-like proliferations of the cervix: diagnostic reproducibility and viral (HPV) correlates

Cervical Pre-cancers: Biopsy and Immunohistochemistry

The existence of precursor lesions for invasive cervical cancer has been recognized for more than 50 years. Our understanding of the pathobiology and behavior of cervical cancer precursors has evolved considerably over the past five decades. Furthermore, the terminology used to classify pre-invasive lesions of the cervix has frequently changed. The realization that human papillomavirus (HPV) infections constitute a morphologic continuum has prompted efforts to include them within a single classification system, specifically the squamous intraepithelial lesions (SILs) which have now been embraced by the surgical pathologists. The reduced number of specific pathological categories has made clinical decision-making more straightforward. The generic criteria for SIL have two important histological parameters: Alterations in the density of superficial epithelial cells and superficial squamous atypia. The flat condyloma or cervical intraepithelial neoplasia (CIN) I is generally associated with intermediate and high-risk HPV types as against the low-risk viruses that cause exophytic/papillary growth patterns of condylomas. The diagnosis of low-grade SIL (LSIL) (flat and exophytic condylomas) requires first excluding benign mimics of LSIL and second to confirm the characteristic cytologic atypia. For high-grade SILs (HSILs), the extent and degree of atypia generally exceed the limits of that described in flat or exophytic condylomas (LSILs). Less maturation, abnormal cell differentiation, loss of cell polarity, and increased mitotic index with abnormal mitotic figures occupying increasing thickness of the epithelium define a lesion as CIN II or CIN III. Atypical immature metaplasia associated with inflammation and atrophy is a challenge in cervical biopsy interpretation. Careful attention to the growth pattern of the epithelium, the distribution of the atypia, nuclear spacing, and the degree of anisokaryosis and the presence of enlarged hyperchromatic nuclei help in differentiating a non-neoplastic from a neoplastic process. This chapter describes in depth the diagnostic difficulties in the interpretation of cervical biopsies. It also provides useful criteria in distinguishing benign mimics from true precancerous lesions and the role of biomarkers such as the p16ink4 and Ki-67 in the differential diagnosis of precursor lesions and the reactive and metaplastic epithelium.

Thin HSIL of the Cervix: Detecting a Variant of High-grade Squamous Intraepithelial Lesions With a p16INK4a Antibody

The WHO defines thin high-grade squamous intraepithelial lesions (HSIL) as a high-grade intraepithelial lesion of the cervix that is usually ≤9 cells thick. These lesions usually develop in early metaplastic squamous epithelium without anteceding low-grade squamous intraepithelial lesions (LSIL). The prevalence of thin HSIL is not well documented. We evaluated different characteristics of thin HSIL at time of treatment. We studied 25 formalin-fixed and paraffin-embedded conization specimens processed as step-serial sections. HSIL≤9 cells thick were classified as thin HSIL. HSIL≥10 cells thick were classified as classic HSIL. Immunohistochemical p16 staining was used to confirm lesions of thin HSIL. Overall, 19 (76%) specimens contained both thin HSIL and classic HSIL, 4 (16%) contained thin HSIL only, 1 (4%) contained classic-type HSIL only, and 1 (4%) contained thin HSIL and LSIL. Thin HSILs developed in both the columnar surface epithelium and deep cervical glandular epithelium. Most thin HSILs were 5 cells thick. All HSILs (thin and classic) were located inside the transformation zone and had a median horizontal extension of 8 mm (range, 0.3 to 21 mm). Our findings suggest that thin HSILs are frequent findings, that they coexist with classic HSIL, and preferably arise in the exposed parts of the transformation zone including the glandular crypts.

A Review and Update on Papillary Immature Metaplasia of the Uterine Cervix: A Distinct Subset of Low-Grade Squamous Intraepithelial Lesion, Proposing a Possible Cell of Origin

Context.—

Papillary immature metaplasia (PIM) is a known papillary cervical lesion associated with low-risk human papillomavirus (LR-HPV).

Objective.—

To evaluate additional clinicopathologic features and the HPV genotypes of PIM and discuss the presumptive cell of origin.

Design.—

A total of 26 PIM cases were evaluated by p16INK4a, cytokeratin (CK) 7, and CK17 immunohistochemical stainings. Human papillomavirus genotyping was performed, by using HPV DNA Chip, HPV polymerase chain reaction (PCR), and real-time PCR.

Results.—

Histologically, PIM forms either a papillary mass (n = 21 of 26, 81%) or a slightly elevated/flat plaque (n = 5, 19%). All cases contain variable amounts of mucinous epithelia within the lesions. Koilocytosis was identified in 15 of the 26 cases (58%). Sixteen cases (61%) were associated with LR-HPV (types 6, 11, or 42), but 3 cases (12%) with high-risk (HR) HPV (16, 16/18, and 33), 2 cases (8%) with mixed LR- and HR-HPV (6/16 and 11/58), while 2 cases (8%) were negative, but p16INK4a immunostaining showed nonblock positivity in all cases. Eight (31%) had high-grade squamous intraepithelial lesion (HSIL) in the adjacent mucosa, 4 (50%) of which showed direct continuity. Identical HPV subtypes were confirmed in separately microdissected cases from PIM and adjacent HSIL. Most lesions (n = 24, 92%) expressed CK17 (reserve cell marker) in a bottom-heavy pattern and CK7 (squamocolumnar junction [SCJ] marker) in a top-heavy pattern, while most cases of low-grade squamous intraepithelial lesion (LSIL) were negative for both markers.

Conclusions.—

Our results suggest that PIM is a distinct subset of LSIL showing a productive HPV infection, but PIM involves the transformation zone and is proximal to SCJ, while LSIL is mostly from ectocervix or distal to the SCJ.

p16 and Ki-67 immunostaining in atypical immature squamous metaplasia of the uterine cervix: correlation with human papillomavirus detection

CONTEXT

Atypical immature squamous metaplasia (AIM) of the cervix is a loosely defined entity characterized by immature metaplastic cells with mild cytologic atypia.

OBJECTIVE

To examine whether a combination of immunostaining for p16 and Ki-67 could be used to stratify AIM cases into 3 categories: benign, cases with nondiagnostic atypia, and high-grade squamous intraepithelial lesion (HSIL).

DESIGN

The study consisted of 37 cases of AIM, 23 cases of benign cervical mucosa (NEG), and 36 cases of HSIL. All cases were tested for high-risk human papillomaviruses using SPF 10 polymerase chain reaction and immunostained for p16 and Ki-67.

RESULTS

All cases of HSIL were positive for both p16 and Ki-67. All but 2 benign control cases were negative for both p16 and Ki-67. Seven cases of AIM (19%) displayed a pattern of immunostaining identical to HSIL, and these most likely represent a spectrum of HSIL. A total of 54% of cases of AIM were negative for both p16 and Ki-67, consistent with benign reactive atypia. Two AIM cases (5%) were negative for p16 and positive for Ki-67 in the area adjacent to an ulcer, representing regeneration. Finally, 22% of AIM cases were positive for p16 and negative for Ki-67; such cases may represent a precursor of HSIL or, alternatively, a regressing HSIL.

CONCLUSION

The combination of immunostaining for p16 and Ki-67 is helpful in limiting of the number of cases with nondiagnostic atypia of the cervix.

Prevalence of cervical neoplastic lesions and Human Papilloma Virus infection in Egypt: National Cervical Cancer Screening Project

Background

Data from Egyptian studies provide widely varying estimates on the prevalence of pre-malignant and malignant cervical abnormalities and human papilloma virus (HPVs) infection. To define the prevalence and risk factors of pre-invasive and invasive cervical cancer (cacx), a community based full-scale cross sectional, household survey including 5453 women aged between 35 and 60 years was conducted.

Methods

The study period was between February 2000 and December 2002. Initially, conventional Papanicolaou (Pap) smears were evaluated using the Bethesda system (TBS), followed by colposcopic guided biopsy (CGB) for all epithelial abnormalities (EA). In a third step, HPV was tested on all EA by in-situ hybridization (ISH) using first the broad spectrum HPV probe recognizing HPVs 6, 11, 16, 18, 30, 31, 35, 45, 51 and 52 followed by subtyping with probes 6/11, 16/18 and 31/33. Lastly, unequivocal cases were immunostained for herpes simplex type-2 (HSV-2), cytomegalovirus (CMV), and human immunodeficiency virus (HIV).

Results

EA representing 7.8% (424/5453), were categorized into atypical squamous cell of undetermined significance (ASCUS) (34.4%), atypical glandular cell of undetermined significance (AGCUS) (15.3%), combined ASCUS and AGCUS (3.1%), low grade squamous intraepithelial lesions (SIL) (41.0%), high grade SIL (5.2%) and invasive lesions (1%). CGB of EA (n = 281) showed non neoplastic lesions (12.8%), atypical squamous metaplasia (ASM) (19.2%), cervical intraepithelial neoplasia I (CIN) (44.4%), CIN II (4.4%), CINIII (2.8%), endocervical lesions (5.2%), combined squamous and endocervical lesions (10.0%), invasive squamous cell carcinoma (SCC) (0.02%) and extranodal marginal zone B cell lymphoma (MZBCL) (0.02%). The overall predictive value of cytology was 87% while the predictive value for high grade lesions was 80%. On histological basis, HPVs were present in 94.3% of squamous lesions while it was difficult to be identified in endocervical ones. ISH revealed positivity for pan HPV in 65.9% of the studied biopsies (n = 217), with incorporation of the viral genome HPV 6/11, 16/18 and 31/33 in 11.1%, 33.3% and 17.1% respectively. Multiple HPVs infections were identified in 0.02%.

Conclusion

Pre-invasive high grade lesions and invasive cervical carcinoma represent 0.5% and 0.04% respectively in Egyptian women. HPV mostly 16/18 as a risk factor (p < 0.001), was frequently associated with mixed infections (p < 0.001) and bilharzial infestation (p < 0.001).

Clonality Analysis and Human Papillomavirus Infection in Squamous Metaplasia and Atypical Immature Metaplasia of Uterine Cervix

Atypical immature squamous metaplasia (ISM) of the uterine cervix often has histological features that overlap with the histological characteristics of high-grade cervical intraepithelial neoplasia. To identify the cellular basis and clinical significance of atypical immature metaplasia (AIM), 10 cases of AIM were analyzed for the clonal status, and the presence of human papillomavirus (HPV) infection. The physical status of HPV was also evaluated in HPV type 16 (HPV-16)-positive cases. Squamous metaplasias with no nuclear atypia (29 mature squamous metaplasias [SMs]) and a single case of ISM were analyzed as a control. Nine AIMs, 20 SMs, and a single case of ISM were informative for clonal analysis. Monoclonal composition of the lesion was demonstrated in 8 (89%) of 9 AIMs, but only in 2 (10%) of 21 cases of SM without atypia (AIM vs SM + ISM, 8/9 vs 2/21; P < 0.0001). High-risk HPV was detected in 6 (60%) of 10 AIMs, all were HPV-16, but only in 3 (13%) of 24 SMs with no atypia (2/23 SM and 1/1 ISM). The frequency of high-risk HPV infection was also significant between AIMs and SM with no atypia (6/10 vs 3/24; P < 0.001). Among the cases, which were informative for clonal analysis, all 5 AIMs positive for high-risk HPV were monoclonal in composition. Physical status of HPV was examined in HPV-16-positive cases. Human papillomavirus type 16 was present as a mixture of episomal form and integrated form in 4 of 6 AIMs. These observations imply that unlike SMs with no atypia, which arises as a result of reactive or inflammatory process, lesions with the histological characteristics of AIM may be indeed true precursors of cervical carcinoma.

Redefining early cervical neoplasia: recent progress

The classification of cervical precancers has evolved over the past 40 years as knowledge concerning the pathogenesis of these human papillomavirus-related lesions has expanded. This commentary reviews the current classification scheme in light of (1) the historical classification systems and (2) the ability of the target epithelium, that is the transformation zone to exhibit varied morphology depending on the cell type that is infected with human papillomavirus. The evolution in our understanding of preinvasive glandular neoplasia is also summarized, with particular attention to so-called superficial (or early) adenocarcinoma in situ. In addition, practical issues in the diagnosis and management of squamous epithelial lesions, particularly the recognition of nonconventional variants and the application of biomarkers, are discussed.

Clinical significance of cytologic diagnosis of atypical squamous cells, cannot exclude high grade, in perimenopausal and postmenopausal women

We used cytohistologic correlation to determine the clinical significance of atypical squamous cells, cannot exclude high grade (ASC-H) in perimenopausal and postmenopausal women. A computer search identified 250 Papanicolaou smears from women older than 45 years with a diagnosis of ASC- H. Cases were considered perimenopausal (45 to < 55 years; 150 cases) and postmenopausal ((3)55 years; 100 cases). No follow-up data were available for 33 cases, which were excluded. The remaining 217 cases (perimenopausal, 127; postmenopausal, 90) had surgical or cytologic follow-up. Results of follow-up colposcopic biopsy were available for 176 (81.1%) and cytology for 41 (18.9%) women. Follow-up results were as follows: perimenopausal women, negative, 50 (39.4%); mild dysplasia (low-grade squamous intraepithelial lesion [LSIL]), 46 (36.2%); high-grade dysplasia (high-grade SIL [HSIL]); 28 (22.0%); and ASC of undetermined significance (ASC-US), 3 (2.4%); postmenopausal women, negative, 52 (58%); LSIL, 31 (34%); HSIL, 5 (6%); and ASC-US, 2 (2%). The diagnosis of ASC-H in postmenopausal women usually is associated with LSIL or a negative diagnosis on follow-up, suggesting a less aggressive surveillance and treatment regimen is needed for postmenopausal women with ASC-H.

p16iNK4a as a complementary marker of high-grade intraepithelial lesions of the uterine cervix. I: Experience with squamous lesions in 189 consecutive cervical biopsies

AIM

To test the usefulness of p16(INK4a) immunostaining for improving the diagnostic accuracy of cervical punch biopsies referred to a routine laboratory setting during the investigation of women with abnormal Papanicolaou smears.

METHODS

A total of 188 consecutive and unselected colposcopically directed cervical biopsies and a single contemporaneous cervical polyp were accessioned prospectively over a 3-month period, step-serially sectioned and examined by H&E and immunostained for p16(INK4a). The clinical context, results of concurrent Papanicolaou smears/ThinPrep slides and Digene hybrid capture tests for high-risk human papillomavirus (HPV) subtypes, as well as follow-up cervical smears/ThinPrep, biopsies and loop excisions of transformation zones or cone biopsies were all correlated with the morphological and immunohistochemical findings.

RESULTS

Seventy-seven biopsies (40.7%) displayed a high-grade squamous intraepithelial lesion (HGSIL; cervical intraepithelial neoplasia [CIN] 2-3), 27 (14.3%) showed a low grade squamous intraepithelial lesion (HPV +/- CIN1) and 85 (45%) showed a range of non-dysplastic (inflammatory or reactive) changes. Diffuse strong parabasal immunostaining for p16(INK4a), suggestive of integrated high-risk HPV DNA into the host genome, was observed in 81 biopsies (42.9%, including the cervical polyp) and correlated (>90%) with HGSIL in the H&E sections. Only one case revealed irreconcilable discordance between the histological features and this strong parabasal immunostaining pattern. Focal and weaker midzonal or superficial p16(INK4a) immunostaining, suggestive of episomal HPV infection, was noted in 19 biopsies (10%) and these biopsies exhibited a range of histological changes but predominantly low grade squamous intraepithelial lesion (LGSIL). No staining of the squamous epithelium was seen in 89 biopsies (47.1%). Again, only one case revealed irreconcilable discordance between the histological features and this negative immunostaining pattern. On review of all cases where discordant results were noted between the H&E appearances and expected p16(INK4a) immunostaining, we found 26 cases (13.7%) in which this discordance prompted justifiable modification of the original diagnosis.

CONCLUSIONS

Thus, within a routine diagnostic laboratory, p16(INK4a) immunostaining appears to be a very useful adjunctive test in the examination of colposcopically directed cervical biopsies, in the diagnostic cascade of women investigated for abnormal Papanicolaou smears. It is possible, as further data accumulate concerning the importance of integration of high-risk HPV DNA into the host cell genome and the reliability with which this can be identified by p16(INK4a) immunostaining, that this will become the diagnostic 'lesion of interest', replacing the subjective histological grading of cervical dysplasia, in the management of such patients; i.e., the discriminatory watershed between continued surveillance and active intervention.

Eosinophilic dysplasia of the cervix: a newly recognized variant of cervical squamous intraepithelial neoplasia

A proportion of cervical squamous intraepithelial lesions encountered in surgical pathology practice contain both metaplastic features and some degree of atypia [so-called eosinophilic dysplasia (ED)] that defy classification according to established criteria. To elucidate the nature of these lesions, we compared 44 cases of ED to 20 classic high-grade squamous intraepithelial lesions (HSILs) and 10 squamous metaplasias using a panel of biomarkers and human papillomavirus (HPV) testing. EDs were defined as 1) lack of normal maturation; 2) relatively abundant eosinophilic cytoplasm and distinct cell borders compared with conventional HSIL; 3) mildly to moderately increased nuclear to cytoplasmic ratio; and 4) focal dysplastic nuclei showing nuclear enlargement, hyperchromasia, variable nuclear membrane irregularities, and appreciable nucleoli. Expression of p16 (p16), MIB-1 (Ki-67) labeling index, and HPV DNA detection and typing were performed on each case. The majority of EDs showed more than three atypical cells in an entire lesion but lack of apparent features of HSIL. It was common to find neighboring cervical squamous metaplasia and/or conventional SILs (either HSIL or low-grade squamous intraepithelial lesion [LSIL]). Among the 44 cases, 18 (45%) ED lesions were found to be associated with HSIL, 15 (34%) with LSIL or condylomatous lesions, and 13 (30%) EDs were seen without any SILs in the entire specimens. Area of benign squamous metaplasia was found in all ED cases. High levels of p16 and MIB-1 expression were seen in 41 (93%) of 44 ED cases with degrees of immunoreactivity closely resembling those seen with HSIL. Of 16 EDs tested, 13 (81%) were positive for HPV DNAs. Among 10 HPV-positive cases subtyped, 9 (90%) cases contained intermediate- and/or high-risk HPVs and 1 case contained a novel HPV. In the follow-up of pure ED cases, the majority showed presence of dysplastic lesions of either HSIL or LSIL on either loop electric excision procedures or Papanicolaou test samples after a 6- to 10-week period. Therefore, ED represents an unrecognized and potentially clinically significant subgroup of cervical intraepithelial lesions. Based on the unique histologic appearance of ED, its association in some cases with HSIL, the overall immunohistochemical findings, frequent association of ED with intermediate- and/or high-risk HPV infection, and limited follow-up data, we believe that ED represents a variant of HSIL (CIN 2). Since ED possesses histologic features of both dysplasia and metaplasia, we speculate that it may arise from metaplastic cervical squamous epithelium that has subsequently become infected with intermediate- or high-risk HPV.

Evaluation of MIB-1-positive cell clusters as a diagnostic marker for cervical intraepithelial neoplasia

The objects of the study were to evaluate MIB-1-positive cell clusters (MIB-C) for distinguishing normal, reactive, and cervical intraepithelial neoplasia (CIN) biopsies and to determine possible pitfalls. Seventy-seven consecutive cervical specimens routinely diagnosed (Dx_orig) as CIN 1 or 2, or no-CIN, were revised independently by two expert gynecopathologists. MIB-1 staining and oncogenic human papillomavirus (HPV) assessment (by polymerase chain reaction) were performed. Independent diagnoses (plus oncogenic HPV status, in case of disagreement between the experts) were used to obtain a final diagnosis (Dx_final) and compared with MIB-C. Four of the 27 (15%) Dx_final = normal were HPV positive. Agreement between the gynecopathologists was 72 of 77 (94%). There were 30 (39%) discrepancies between Dx_orig and Dx_final (23 = 30% downgrades and 7 = 9% upgrades). All 23 downgrades were HPV negative and all seven upgrades were HPV positive. Overall agreement between Dx_orig and MIB-C was 73%, and with Dx_final 99%. Sensitivity, specificity, and positive and negative predictive values of MIB-C were very high without false negatives. Tangential cutting of MIB-1-positive parabasal cells and inflammatory cells can erroneously be overdiagnosed as a MIB-C. One single false positive of the 48 non-CIN cases (an immature squamous metaplasia) showed a special, easily recognizable MIB-1 pattern, different from CIN because the MIB-1 staining in the nuclei is not diffuse (as in CIN) but clumped. Moreover, positive nuclei are somewhat less densely packed than in CIN. When tangentially cut parabasal cells and inflammatory cells are carefully excluded, MIB-C is a strong diagnostic adjunct in distinguishing CIN from normal or benign cervical squamoepithelial lesions.

[Metaplasia and high grade CIN. Diagnostic difficulties]

Squamous metaplasia of cervix represents the physiologic process of transformation of eversed glandular tissue at external orifice by a malpighian tissue. Primarily undifferentiated and immature, the epithelium progressively becomes differentiated and takes glycogen. In a high grade CIN the normal squamous epithelium is replaced by an undifferentiated tissue comporting basal cells with nuclear atypias. When cellular abnormalities are not marked, differential diagnosis exists with immature metaplasia. Cytology with suspicion of squamous intraepithelial lesion is sometimes followed by a diagnosis of high grade CIN on biopsy, but conisation reveals a metaplasia.

Relationship between the presence of oncogenic HPV DNA assessed by polymerase chain reaction and Ki-67 immunoquantitative features in cervical intraepithelial neoplasia

The aims of this study were firstly to determine which Ki-67 immunoquantitative parameters correlate with the presence of oncogenic human papillomavirus (HPV) in cervical intraepithelial neoplasia (CIN) lesions; and secondly to compare prospectively the routinely assessed CIN grades with the Ki-67 quantitative pathological CIN grade, the expert revised grade, and the presence of oncogenic HPV DNA. HPV polymerase chain reaction (PCR) and Ki-67 immunoquantitation were performed on 90 consecutive biopsies (16 CIN 1, 35 CIN 2, and 39 CIN 3). CIN grade was assessed routinely by six different pathologists. The presence of the lesion was confirmed in a histological section following the material used for PCR and Ki-67 analysis. In a second prospective routine test set analysis, 66 more CIN lesions (14 CIN 1, 15 CIN 2, and 37 CIN 3) were routinely graded (also by six different pathologists, routine CIN grade=CIN(ROUT)), studied for oncogenic HPV DNA, and graded by quantitative Ki-67 features (quantitative pathological CIN grade=CIN(QP)). These latter cases were blindly revised by one of the authors (reference CIN grade=CIN(REF)). Eight of the nine Ki-67 immunoquantitative features showed a significant difference between the oncogenic HPV-positive and -negative cases. The best single discriminator was the 90th percentile of the stratification index (SI90). All 61 cases with Ki-67 SI90>0.60 were HPV-positive (68% of the total group studied). Of the 29 cases with SI90< or =0.60, 16 were negative and 13 positive for oncogenic HPV and none of the Ki-67 features (either single or combined) could distinguish them. Using stepwise multivariate analysis, the best discriminating combination of features was SI90 and the percentage of Ki-67-positive nuclei in the deep third layer of the epithelium (PERC DL). The combination of SI90 and the percentage of Ki-67-positive nuclei per 100 microm basal membrane was nearly as strong as that of SI90 and PERC DL. With these two features, 86% of the cases were correctly classified. The subjective estimate of SI90 (>0.60 or < or =0.60) by two independent observers was not accurate and not reproducible. In the prospective routine test set analysis of 66 cases, the 37 CIN(ROUT)=3 all had CIN(QP) and CIN(REF)=3 and all these cases were oncogenic HPV-positive. Eight of the 14 original CIN(ROUT)=1 grades were oncogenic HPV (=HPV)-positive and five of these eight were upgraded by CIN(QP) to CIN 2 and CIN 3. These upgrades were in agreement with the blind reference revisions. The six HPV-negative CIN(ROUT)=1 cases were CIN 1 both by CIN(QP) and by CIN(REF). Thirteen of the 15 original CIN(ROUT)=2 grades were HPV-positive and seven of these were CIN(QP)=3. All six HPV-positive CIN(ROUT)=2 cases that were CIN(QP)=2 were also CIN(REF)=2 at blind revision. In conclusion, this study has shown firstly, that in CIN lesions, Ki-67 immunoquantitative features and the presence of oncogenic HPV are highly correlated, and also within one subjective CIN grade; secondly, that subjective impressions of SI90 are not as accurate or reproducible as quantitative image analysis results; and thirdly, that the routine application of QP CIN-grading gives results that are in very good agreement with CIN grades assessed by an expert. Thus, routine QP-grading may be used to correct the subjective grade assessed by non-expert pathologists.

Ki-67, cyclin E, and p16INK4 are complimentary surrogate biomarkers for human papilloma virus-related cervical neoplasia

Prior studies of Ki-67, cyclin E, and p16 expression have suggested that these biomarkers may be preferentially expressed in cervical neoplasia. This study examined and compared the distribution of staining for these three antigens in 1) normal and reactive epithelial changes, 2) diagnostically challenging cases (atypical metaplasia and atypical atrophy), 3) squamous intraepithelial lesions (SIL), and 4) high-and low-risk human papilloma virus (HPV) type-specific SIL. One hundred four epithelial foci from 99 biopsies were studied, including low-grade squamous intraepithelial lesions (LSIL; 24), high-grade squamous intraepithelial lesions (HSIL; 36), mature or immature (metaplastic) squamous epithelium (29), and atrophic or metaplastic epithelium with atypia (15). Cases were scored positive for Ki-67 expression if expression extended above the basal one third of the epithelium, for cyclin E if moderate to strong staining was present, and for p16 if moderate to strong diffuse or focal staining was present. HPV status was scored by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of extracted DNA. Immunohistochemical findings were correlated with histologic and viral data. Overall, a histologic diagnosis of SIL correlated strongly with all of the biomarkers used (p <0.001). Positive scores for Ki-67, cyclin E, and p16 were seen in 68.4%, 96.7%, and 100% of LSILs and 94.7%, 91.6%, and 100% of HSILs, respectively. Positive predictive values of these three biomarkers for HPV were 82.4%, 89.5%, and 91.4%, respectively. The positive predictive value for HPV of either cyclin E or p16 was 88.7%. Strong diffuse staining for p16 was significantly associated with high-risk HPV-associated lesions. Normal or reactive epithelial changes scored positive for the three biomarkers in 7.7%, 8.0%, and 12%, respectively. Limitations in specificity included minimal or no suprabasal staining for Ki-67 in immature condylomas and occasional suprabasal staining of reactive epithelial changes (10%), diffuse weak nuclear cyclin E staining in some normal or metaplastic epithelia, and diffuse weak basal p16 staining and occasional stronger focal positivity in normal epithelia. Ki-67, cyclin E, and p16 are complementary surrogate biomarkers for HPV-related preinvasive squamous cervical disease. (Because cyclin E and p16 are most sensitive for LSIL and HSIL [including high-risk HPV], respectively, use of these biomarkers in combination for resolving diagnostic problems, with an appreciation of potential background staining, is recommended.)

Significance of a diagnosis of atypical squamous cells of undetermined significance for Papanicolaou smears in perimenopausal and postmenopausal women

BACKGROUND

The current study was conducted to determine the significance of a diagnosis of atypical squamous cells of undetermined significance (ASCUS) in perimenopausal and postmenopausal women.

METHODS

The reports for all Papanicolaou (Pap) smears viewed in the study institution's cytology laboratory over a 6-month period were reviewed. Women were divided into premenopausal (age < or = 45 years), perimenopausal (ages 46-54 years), and postmenopausal (age > or = 55 years) categories. Slide review and 2-year follow-up were obtained for selected cases diagnosed as ASCUS. ASCUS cases among the perimenopausal women were compared with an age-matched control group.

RESULTS

The total number of abnormal Pap smears in the premenopausal, perimenopausal, and postmenopausal categories were 770 (6.8%), 104 (4.3%), and 67 (2.9%), with 482, 83, and 41 diagnoses of ASCUS, respectively. The ratio of ASCUS to squamous intraepithelial lesions (SIL) was 2.2 overall and 1.9, 7.5, and 4.1, respectively, for each group (P < 0.001). The positive predictive value for a diagnosis of SIL on subsequent Pap smears or biopsies was 22%, 12.2%, and 29.7%, respectively. Slide review showed that the premenopausal ASCUS cases appeared to have a higher percentage of nuclear-cytoplasmic ratio increase and nuclear membrane irregularities compared with the other categories (P = 0.03 and P = 0.02, respectively) and the perimenopausal group was found to have more ASCUS in metaplastic cells (P = 0.03). In perimenopausal women, slides diagnosed as ASCUS demonstrated more air-drying artifact than the control group (P = 0.004) but had less obvious atrophy (P = 0.01).

CONCLUSIONS

Despite a decreased abnormality rate with increasing age, the results of the current study show that the perimenopausal and postmenopausal groups appear to have elevated ASCUS-to-SIL ratios. ASCUS appears to have a particularly low positive predictive value for SIL in perimenopausal women, and therefore most likely is overcalled in this age group. This may be attributable in part to air-drying artifact and subtle atrophic changes.

Contemporary theories of cervical carcinogenesis: the virus, the host, and the stem cell

Cervical cancer is a complex disease that, by its association with human papillomavirus (HPV), has elicited research in a broad range of areas pertaining to its basic diagnostic and clinical aspects. The complexity of this association lies not only in the fundamental relationship between virus and cancer but also in its translation to pathologic diagnosis and clinical management. Offshoots from the relationship of virus to pathology include studies targeting the link between papillomavirus infection and cervical epithelial abnormalities, the molecular epidemiology of papillomavirus infection, and the potential use of HPV testing as either a screening technique or a tool for managing women who have Pap smear abnormalities. A second variable that is critical to the pathogenesis of cervical neoplasia is the cervical transformation zone. The wide range of invasive and noninvasive lesion phenotypes associated with HPV infection in this region indicate that not only the virus but also specific host target epithelial cells in the transformation zone play an important part in the development of cervical neoplasia. Further understanding of this relationship between the virus and the host epithelium will hinge on determining the subtypes of epithelial cells in the transformation zone and their phenotypic response to infection. New technologies, such as expression arrays, promise to clarify, if not resolve, the complexity of molecular interactions leading to the multiplicity of tumor phenotypes associated with HPV infection of the uterine cervix.