Molecular and pathological basis of HPV-negative cervical adenocarcinoma seen in a global study.

International surveys find HPV-negativity in up to 30% of cervical adenocarcinomas. We investigated the pathological diagnosis by expert consensus with immunohistochemistry and the presence of somatic mutations in recognised tumour genes in HPV-positive and negative cervical adenocarcinomas (CADC). A sample was selected of 45 paraffin-embedded cervical blocks diagnosed locally as usual cervical adenocarcinoma from a global study. These represented different diagnoses made at previous diagnostic review and HPV status. All were suitable for analysis for somatic tumour associated gene mutations. Three pathologists examined H/E slides and immunohistochemistry for p16, progesterone receptor and p53 and classified the cases. L1 genes from high-risk HPVs and low-risk HPVs were analysed by SPF10 PCR-DEIA-LiPA25 version 1 in whole tissue sections and microdissected tumour and retested by PCR for E6/E7 genes of hrHPVs if negative. Cases were analysed for microsatellite instability and next-generation sequencing mutation analysis. From the 45 cases, 20 cases of usual CADC were confirmed of which 17 (85%) were HPV-positive in tumour cells. The other 25 cases were reclassified as endometrial, serous, clear-cell and gastric-type adenocarcinomas and all were HPV-negative in tumour cells. Careful retesting for HPV DNA and IHC leads to more accurate identification of HPV-positive usual cervical adenocarcinomas. Endometrioid endometrial adenocarcinomas, other uterine adenocarcinoma with multiple somatic mutations were important in misclassification of HPV-negative cases locally managed as cervical adenocarcinoma, as was gastric-type adenocarcinoma with germline STK11 mutation in East Asia. Few consensuses confirmed HPV-negative usual cervical adenocarcinomas showed somatic tumorigenic mutations also seen in some HPV-positive usual CADC.

p16 Positive Histologically Bland Squamous Metaplasia of the Cervix: What does It Signify?

With increasing use of p16 immunohistochemistry (IHC) in diagnosis of premalignant lesions of cervix, we occasionally encounter p16 positivity in squamous metaplasia that lacks morphologic characteristics of "atypical squamous metaplasia" or of squamous intraepithelial lesion (SIL). Our study aims to investigate if transcriptionally active human papilloma virus (HPV) can be identified in such foci and if they have any relationship with squamo-columnar junction (SCJ) cells. Twenty-two cases of cervical specimens with at least a focus of p16 positive bland squamous metaplasia, were selected. HPV E6/E7 mRNA in situ hybridization followed by IHC for CK7 (SCJ biomarker), Ki67, and HPV16 E2, were performed. Follow-up information was obtained. Four cases were excluded due to insufficient tissue. Of the final 18 cases, HPV E6/E7 mRNA in situ hybridization was positive in all. Nine cases showed positivity in >50% cells and the epithelial thickness involved was ≥lower two-thirds in 13 cases. Of the further evaluable 15 cases, CK7 was positive in 14, Ki67 was positive in 10, and HPV16 E2 was negative in all. Concomitant high-grade squamous intraepithelial lesion was identified in 10 cases. On follow-up (duration: 1 to 19 mo), 6 patients showed histologic high-grade squamous intraepithelial lesion. Our study demonstrates that p16 positivity in squamous metaplasia of cervix is associated with the presence of transcriptionally active high-risk HPV even when there are no clear morphologic features of dysplasia. Our results suggest that these lesions are early SILs or SILs that are not yet morphologically evident, most of which arise from SCJ and should be closely followed.

Gastric-type Adenocarcinoma of the Cervix: Tumor With Wide Range of Histologic Appearances.

Gastric-type endocervical adenocarcinoma (GAS) is a recently described diagnostic entity originally characterized as a tumor with (1) voluminous cytoplasm that is (2) clear or pale eosinophilic, and (3) cells showing distinct cell borders. Since the initial tumor description there has been accumulating experience that the neoplasm, in addition to classic features, may show a wide spectrum of morphologic appearances. This paper describes and illustrates cases of GAS with focal or diffuse findings that include: densely eosinophilic cytoplasm, foamy cytoplasm, goblet cells, glands with elongated, stratified nuclei, glands with small cuboidal cells, glands with flattened cells, papillary growth, single cell infiltration and infiltration with microcystic elongated and fragmented pattern. All these patterns may bring up a differential diagnosis with other cervical malignancies such as usual, intestinal, endometrioid, clear cell, serous, and mesonephric adenocarcinoma. The paper describes the patterns of immunostaining of respective lesions that may aid in the diagnostic process and summarizes the main points of the differential diagnosis. GAS is associated with somatic and germline STK11 mutations and TP53 mutations but is invariably negative for human papilloma virus when tumor only is tested. It shows variation in incidence between countries. Awareness of the spectrum of morphologic appearances in GAS is important for accurate and confident diagnosis. Correct identification of GAS is important due to its propensity for ovarian and other distant metastases, markedly worse prognosis as compared with usual endocervical adenocarcinoma, and its relative resistance to chemotherapy.

Utility of Stathmin-1 as a Novel Marker in Evaluating Anal Intraepithelial Neoplasia (AIN).

The aim of this study is to determine whether immunohistochemistry for Stathmin-1 enhances diagnostic accuracy of anal dysplasia. The study included 40 biopsies with diagnosis of benign anal transitional zone (n=10), low-grade anal intraepithelial neoplasia (AIN) (AIN1, n=10), and high-grade AIN (AIN2, n=10, AIN3, n=10). The cases were selected to represent classic features. Immunohistochemistry for Stathmin-1, p16, and Ki-67 was performed and assessed for distribution within epithelial thickness. Stathmin-1 was expressed only in the basal layer of benign anal epithelium. Similar pattern of distribution was seen in all low-grade AIN cases (100%). In total, 40% of AIN2 showed Stathmin-1 staining pattern similar to AIN1. The other 60% of cases showed staining extending into the middle third of the epithelial thickness. Of AIN3 cases, 20% showed staining confined to the lower third epithelium, 20% showed staining extending to the middle third, and 60% showed staining extending into the upper third epithelium. The pattern of stain distribution suggested that staining extending above the lower one-third of the epithelial thickness discriminates between low-grade and high-grade AIN. With this cutoff, the sensitivity for the diagnosis of high-grade AIN was 70%, specificity was 100%, positive predictive value equaled 100%, and negative predictive value equaled 77%. P16INK4a showed 100% sensitivity for AIN2 and AIN3, whereas Ki-67 had 100% sensitivity for any AIN grade. In conclusion, Stathmin-1 has excellent specificity for the diagnosis of high-grade AIN; however, Stathmin-1 alone may not be sufficiently sensitive. Use in conjunction with other sensitive markers, such as p16 or Ki-67 may be considered.

Fluorescence microscopy of H&E stained cervical biopsies to assist the diagnosis and grading of CIN.

BACKGROUND: Prevention of cervical cancer is based upon the accurate diagnosis and grading of cervical lesions identified during screening. The pathological classification of cervical intraepithelial neoplasia (CIN) is problematic, as it relies on subjective criteria and is known to have high interobserver variability and low reproducibility. These limitations can result in either over or under treatment of patients. Biomarkers to improve CIN diagnosis have not overcome all these challenges. MAIN BODY: Here we review the use of a promising optical imaging method using eosin-based fluorescence spectroscopy. This technique is able to perform fluorescent analysis of cervical biopsies directly from hematoxylin and eosin (H&E) stained tissues. Eosin is a brominated derivative of fluorescein. Fluorescence characteristics of protein-eosin complexes can demonstrate tissue changes associated with dysplasia and cancer. In this article we review the progress made towards developing eosin-based fluorescence spectroscopy. We describe the various morphologies seen among the CIN grades with this optical method and highlight the progress made to quantitate the spectral image characteristics. CONCLUSION: Eosin-based fluorescence spectroscopy can be used to directly examine H&E stained tissue slides. Relevant areas can be imaged and spectral analysis done to obtain objective data to identify and grade cervical lesions.

Presence or Absence of Significant HPVE4 Expression in High-grade Anal Intraepithelial Neoplasia With p16/Ki-67 Positivity Indicates Distinct Patterns of Neoplasia: A Study Combining Immunohistochemistry and Laser Capture Microdissection PCR.

Progression of anal intraepithelial neoplasia (AIN) involves transition from productive to transforming human papillomavirus (HPV) infection. Grading aims to distinguish productive low-grade AIN from high-grade anal intraepithelial neoplasia (HGAIN) with risk of cancer. We describe immunohistochemical patterns in AIN adding a novel marker for initiation of the productive phase of the HPV life cycle (panHPVE4) to those for cell cycle activity (Ki-67) and transforming activity of HPVE7 gene (p16). We studied 67 anal biopsies for suspected anal neoplasia (17 normal, 15 AIN1, 20 AIN2, 15 AIN3) from 54 men who have sex with men at New York Presbyterian Hospital, USA. Two pathologists generated consensus AIN and immunogrades. Whole tissue and laser capture microdissection samples from multiple HPV-infected biopsies were tested for HPV with SPF10-PCR-DEIA-LiPA25, version 1. (Para)basal Ki-67 expression distinguished normal from AIN (≥lower-third Ki-67) with sensitivity 0.92 and specificity 1.0. Ki-67 did not distinguish grades of AIN. Null/patchy p16 versus diffuse ≥lower-third patterns discriminated HGAIN (sensitivity, 1.0; specificity, 0.84). There was marked heterogeneity in E4 expression within HGAIN. Most AIN2 (14/20) was E4 versus 0/15 AIN3 (sensitivity, 0.70; specificity 1.0). HPV was detected in 63 (94%) biopsies, with 49 (77.8%) high-risk HPV. HPV16 was the most frequent (13%). Multiple HPV genotypes were found in 15 (24%) biopsies and laser capture microdissection -polymerase chain reaction confirmed specific HPV types in E4 +/- AIN. Although Ki-67 discriminated AIN and p16 HGAIN, E4/p16 staining shows that most AIN2 is different from transformed AIN3 in showing both entry into productive HPV infection and transforming activity.

Novel Fumarate Hydratase Mutation in Siblings With Early Onset Uterine Leiomyomas and Hereditary Leiomyomatosis and Renal Cell Cancer Syndrome.

Hereditary leiomyomatosis renal cell cancer syndrome is an autosomal dominant disorder characterized by uterine and cutaneous leiomyomas and increased predisposition to renal cell carcinoma, papillary type II. The syndrome is caused by heterozygous mutations to the fumarate hydratase (FH) gene located on chromosome 1. Affected females generally present with early onset, atypical uterine leiomyomas and cutaneous findings, however, delays in diagnosis are very common in patients with isolated uterine findings. We present a case series of 2 sisters in their 20s who presented with isolated uterine leiomyomas and were found to carry a novel mutation for the fumarate hydratase gene. One patient was referred for treatment of infertility and recurrent miscarriages and the other was referred for acute symptomatic anemia due to myomas. Prompt diagnosis of hereditary leiomyomatosis renal cell cancer was made due to a high index of clinical suspicion based on early onset disease and familial clustering as well as characteristic pathologic findings on uterine leiomyoma surgical specimen. Timely diagnosis not only allowed for genetic counseling and renal cancer surveillance, but also for fertility counseling given the increased morbidity associated with uterine leiomyoma due to hereditary leiomyomatosis and renal cell cancer syndrome.

Despite Diagnostic Morphology, Many Mixed Endometrial Carcinomas Show Unexpected Immunohistochemical Staining Patterns.

Historically, endometrial carcinomas have been classified primarily according to their histology. However, the use of immunohistochemistry has become commonplace in their evaluation, particularly in diagnostically challenging cases. Our objective was to evaluate mixed endometrial carcinomas using a well-established panel of biomarkers to assess the consistency and utility of these stains in clinical diagnosis. Eighteen cases comprised of various combinations of classical serous (SC), endometrioid (EC), and clear cell (CC) morphologies were identified and subjected to a panel of immunohistochemical markers including p53, p16, Ki67, estrogen receptor, progesterone receptor, and Napsin A. Intensity and extent of staining were evaluated on 4-tiered and 5-tiered scales, respectively. The typical immunostaining pattern expected for the individual tumor components was seen in only 3 cases, while in 15 cases an unexpected pattern was observed with at least one immunomarker. By tumor type, the most common unexpected finding in EC/SC carcinoma cases was diffuse positivity for p16 and/or estrogen receptor/progesterone receptor in both components, while in SC/CC, diffuse positivity for p53 in both components was most frequently seen, and in SC/CC/EC, Napsin A negativity was most commonly observed. Despite displaying diagnostic morphology, components of many mixed endometrial carcinomas may not exhibit expected immunohistochemical features. This may be due to the fact that these carcinomas arise from a single clone with subsequent divergence, resulting in a tumor with both mixed histologic and genetic features. It is important to note that these tumors may not demonstrate the immunohistochemical prototype of their constituents and should be approached accordingly from a diagnostic perspective.

Cervical Adenocarcinoma: Diagnosis of Human Papillomavirus-Positive and Human Papillomavirus-Negative Tumors.

CONTEXT: - Cervical adenocarcinomas span a diverse group of tumors with several distinct histologic tumor types, which include endocervical, endometrioid, intestinal, villoglandular, gastric, signet ring, serous, clear cell, and mesonephric. Diagnosis of cervical adenocarcinoma, especially early diagnosis, poses a significant challenge. OBJECTIVE: - To review the pathogenesis, diagnostic criteria, immunohistochemical markers, and differential diagnosis of various subtypes of human papillomavirus (HPV)-positive and HPV-negative cervical adenocarcinomas. The paper presents a concise summary of the issues that may be particularly difficult in histopathologic diagnosis, such as differentiating neoplastic lesions from benign mimics, determining the tumor type, differentiating early invasive lesions from adenocarcinoma in situ, measuring the depth of invasion, and, finally, differentiating primary cervical adenocarcinoma from uterine endometrioid adenocarcinoma and tumors metastatic from other primary sites. DATA SOURCES: - The study employed a PubMed search of recently published reports. CONCLUSIONS: - Early detection of HPV-positive tumor types may be aided with the expansion of HPV testing; however, early diagnosis of HPV-negative cervical adenocarcinomas will continue to pose a challenge and may require the development of additional molecular testing techniques.

Prostate-specific Membrane Antigen (PSMA) Expression in the Neovasculature of Gynecologic Malignancies: Implications for PSMA-targeted Therapy.

The goal of the study was to examine expression of prostate-specific membrane antigen (PSMA) in neovasculature of gynecologic cancers, as PSMA-targeted therapy has showed a promise in treatment of advanced carcinomas. The study included cervical carcinoma (n=28), vulvar carcinoma (n=20), endometrial carcinoma (n=23), primary ovarian carcinoma (n=21), metastatic ovarian carcinoma (n=25), and normal cervix (n=12) as negative control. All cases were immunostained using anti-CD31 antibody to delineate capillary endothelial cells. In parallel, all cases were immunostained using anti-PSMA antibody. The PSMA staining was assessed in tumor capillaries and in normal tissues and scored as a percentage of CD31 staining. PSMA expression was found in the tumor neovasculature, and no significant expression was identified in vasculature of normal tissues. The extent of PSMA staining in tumor capillaries varied from high expression in ovarian and endometrial cancers, to medium expression in cervical squamous cell carcinomas, and low expression in cervical adenocarcinomas and vulvar cancers. All (100%) cases of primary ovarian carcinoma, ovarian carcinoma metastases, and primary endometrial carcinoma showed PSMA expression in tumor vasculature, which was diffuse in majority of cases. The expression of PSMA in ovarian cancer metastases was similar among different metastatic foci of the same tumor. Fifteen percent of cervical squamous cell carcinoma, 50% of cervical adenocarcinoma, and 75% of vulvar carcinomas showed no capillary expression of PSMA. In conclusion, PSMA is highly and specifically expressed in the neovasculature of ovarian, endometrial, and cervical squamous carcinoma, rendering it a potential therapeutic vascular target.

The metabolic/pH sensor soluble adenylyl cyclase is a tumor suppressor protein.

cAMP signaling pathways can both stimulate and inhibit the development of cancer; however, the sources of cAMP important for tumorigenesis remain poorly understood. Soluble adenylyl cyclase (sAC) is a non-canonical, evolutionarily conserved, nutrient- and pH-sensing source of cAMP. sAC has been implicated in the metastatic potential of certain cancers, and it is differentially localized in human cancers as compared to benign tissues. We now show that sAC expression is reduced in many human cancers. Loss of sAC increases cellular transformation in vitro and malignant progression in vivo. These data identify the metabolic/pH sensor soluble adenylyl cyclase as a previously unappreciated tumor suppressor protein.

HPV Involvement in Head and Neck Cancers: Comprehensive Assessment of Biomarkers in 3680 Patients.

BACKGROUND: We conducted a large international study to estimate fractions of head and neck cancers (HNCs) attributable to human papillomavirus (HPV-AFs) using six HPV-related biomarkers of viral detection, transcription, and cellular transformation. METHODS: Formalin-fixed, paraffin-embedded cancer tissues of the oral cavity (OC), pharynx, and larynx were collected from pathology archives in 29 countries. All samples were subject to histopathological evaluation, DNA quality control, and HPV-DNA detection. Samples containing HPV-DNA were further subject to HPV E6*I mRNA detection and to p16(INK4a), pRb, p53, and Cyclin D1 immunohistochemistry. Final estimates of HPV-AFs were based on HPV-DNA, HPV E6*I mRNA, and/or p16(INK4a) results. RESULTS: A total of 3680 samples yielded valid results: 1374 pharyngeal, 1264 OC, and 1042 laryngeal cancers. HPV-AF estimates based on positivity for HPV-DNA, and for either HPV E6*I mRNA or p16(INK4a), were 22.4%, 4.4%, and 3.5% for cancers of the oropharynx, OC, and larynx, respectively, and 18.5%, 3.0%, and 1.5% when requiring simultaneous positivity for all three markers. HPV16 was largely the most common type. Estimates of HPV-AF in the oropharynx were highest in South America, Central and Eastern Europe, and Northern Europe, and lowest in Southern Europe. Women showed higher HPV-AFs than men for cancers of the oropharynx in Europe and for the larynx in Central-South America. CONCLUSIONS: HPV contribution to HNCs is substantial but highly heterogeneous by cancer site, region, and sex. This study, the largest exploring HPV attribution in HNCs, confirms the important role of HPVs in oropharyngeal cancer and drastically downplays the previously reported involvement of HPVs in the other HNCs.

Detection of in situ and invasive endocervical adenocarcinoma on ThinPrep Pap Test: Morphologic analysis of false negative cases.

BACKGROUND: The goal of this study was to calculate the sensitivity and false negative (FN) rate of ThinPrep Pap Test (TPPT) and carefully analyze missed cases for educational purposes. MATERIALS AND METHODS: Patients with histologically proven adenocarcinoma in-situ (AIS) or invasive endocervical adenocarcinoma (EAC) over a 17-year-period (1998-2015) were identified. The TPPT immediately preceding the histological diagnosis of AIS/ECA was designated as index Pap (IP). Paps up to 122 months before histologic diagnosis of AIS/ECA were considered for this study. All available negative and unsatisfactory TPPT were re-reviewed. RESULTS: There were 78 patients with histologically-proven AIS (56) or ECA (22) with 184 TPPTs, and 95 of these TPPTs were abnormal. Of the abnormal cases, 55.7% TPPTs were diagnosed as endocervical cell abnormality (atypical endocervical cells/AIS/ECA). Notably, 44.2% of abnormal TPPTs were diagnosed as squamous cell abnormality (atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesion/high grade squamous intraepithelial lesion). Including the diagnoses of squamous cell abnormality, the sensitivity of index TPPT for histologically-confirmed AIS/ECA was 88%. Eighty-eight of 184 TPPT, including 10 IP, were negative = 87, or unsatisfactory = 1. Forty-two of these slides were available for re-review. Upon review, 21 TPPT (50%) were confirmed negative and 21 TPPT (50%) were reclassified as abnormal = 20, or unsatisfactory = 1. Of the FN cases, the main difficulty in correct diagnosis was the presence of few diagnostic cell clusters which had less feathering, and consisted of smaller, rounder cells in small and tighter clusters, with nuclear overlap. In particular, nuclear overlap in three-dimensional groups precluded the accurate diagnosis. Rare FN cases showed squamous cell abnormality on re-review, and rare cases showed obscuring blood or inflammation. CONCLUSION: A significant proportion of AIS/EAC is discovered after Pap showing squamous cell abnormality. FN cases were most commonly related to nuclear overlap in tight three-dimensional clusters.

High grade endometrial stromal sarcoma on thinprep.

High grade endometrial stromal sarcoma (HGESS) is an uncommon malignancy recently re-defined in the new WHO classification of endometrial stromal tumors. In this article, we discuss the differential diagnoses of metastatic HGESS in a fine needle aspiration (FNA) of a lymph node and compare the cytomorphology of HGESS in ThinPrep [(TP), Hologic Inc., Boxborough, MA] to conventional smears (CS). The patient had a history of stage I HGESS, status-post supracervical hysterectomy without regional lymph node metastases. Her post-operative course was complicated by pelvic fluid collections and enlarging para-aortic lymph nodes. Diff-Quik (DQ)-stained and Papanicolaou (Pap)-stained smears from a para-aortic lymph node FNA demonstrated a cellular specimen with monomorphic population of plump to oval cells with scant, wispy cytoplasm in aggregates and as single cells. The nuclei showed fine chromatin and small inconspicuous nucleoli. Compared to the CS, HGESS cells in the TP showed similar cytological features, with the exception that the nuclei were slightly smaller, hyperchromatic, and the chromatin pattern was attenuated. In the absence of prior clinical history, the cytomorphology of metastatic HGESS in a lymph node can be difficult to differentiate from a lymphoma, a variety of metastatic spindle cell tumors or metastatic carcinoma. Immunohistochemical analysis and comparison with the primary tumor can be useful in proving the nature of the malignant cells. The cytomorphology of HGESS on TP correlated well in both single cells and aggregates when compared to CS. The differences noted were decreased nuclear size, nuclear hyperchromasia, and slightly attenuated nuclear detail on TP.

Diagnostic imaging of cervical intraepithelial neoplasia based on hematoxylin and eosin fluorescence.

BACKGROUND: Pathological classification of cervical intraepithelial neoplasia (CIN) is problematic as it relies on subjective criteria. We developed an imaging method that uses spectroscopy to assess the fluorescent intensity of cervical biopsies derived directly from hematoxylin and eosin (H&E) stained tissues. METHODS: Archived H&E slides were identified containing normal cervical tissue, CIN I, and CIN III cases, from a Community Hospital and an Academic Medical Center. Cases were obtained by consensus review of at least 2 senior pathologists. Images from H&E slides were captured first with bright field illumination and then with fluorescent illumination. We used a Zeiss Axio Observer Z1 microscope and an AxioVision 4.6.3-AP1 camera at excitation wavelength of 450-490 nm with emission captured at 515-565 nm. The 32-bit grayscale fluorescence images were used for image analysis. RESULTS: We reviewed 108 slides: 46 normal, 33 CIN I and 29 CIN III. Fluorescent intensity increased progressively in normal epithelial tissue as cells matured and advanced from the basal to superficial regions of the epithelium. In CIN I cases this change was less prominent as compared to normal. In high grade CIN lesions, there was a slight or no increase in fluorescent intensity. All groups examined were statistically different. CONCLUSION: Presently, there are no markers to help in classification of CIN I-III lesions. Our imaging method may complement standard H&E pathological review and provide objective criteria to support the CIN diagnosis.

Human papillomavirus prevalence and type-distribution in cervical glandular neoplasias: Results from a European multinational epidemiological study.

Cervical glandular neoplasias (CGN) present a challenge for cervical cancer prevention due to their complex histopathology and difficulties in detecting preinvasive stages with current screening practices. Reports of human papillomavirus (HPV) prevalence and type-distribution in CGN vary, providing uncertain evidence to support prophylactic vaccination and HPV screening. This study [108288/108290] assessed HPV prevalence and type-distribution in women diagnosed with cervical adenocarcinoma in situ (AIS, N = 49), adenosquamous carcinoma (ASC, N = 104), and various adenocarcinoma subtypes (ADC, N = 461) from 17 European countries, using centralised pathology review and sensitive HPV testing. The highest HPV-positivity rates were observed in AIS (93.9%), ASC (85.6%), and usual-type ADC (90.4%), with much lower rates in rarer ADC subtypes (clear-cell: 27.6%; serous: 30.4%; endometrioid: 12.9%; gastric-type: 0%). The most common HPV types were restricted to HPV16/18/45, accounting for 98.3% of all HPV-positive ADC. There were variations in HPV prevalence and ADC type-distribution by country. Age at diagnosis differed by ADC subtype, with usual-type diagnosed in younger women (median: 43 years) compared to rarer subtypes (medians between 57 and 66 years). Moreover, HPV-positive ADC cases were younger than HPV-negative ADC. The six years difference in median age for women with AIS compared to those with usual-type ADC suggests that cytological screening for AIS may be suboptimal. Since the great majority of CGN are HPV16/18/45-positive, the incorporation of prophylactic vaccination and HPV testing in cervical cancer screening are important prevention strategies. Our results suggest that special attention should be given to certain rarer ADC subtypes as most appear to be unrelated to HPV.

Immunohistochemistry and in situ hybridization for the diagnosis and classification of squamous lesions of the anogenital region.

Distinguishing anogenital squamous intraepithelial lesions from benign conditions and mimics may be problematic. Immunohistochemistry for surrogate markers of HPV infection, such as Ki-67, p16, and ProEx™ C, may aid the diagnosis in equivocal cases. The main diagnostic pitfall in the diagnosis of LSIL is the occurrence of "pseudokoilocytes" in benign squamous mucosa, which may lead to overdiagnosis. When interpreted correctly, Ki-67 is a sensitive and specific marker for dysplasia in mature squamous epithelium and is therefore useful for confirmation of LSIL and condyloma. A Ki-67 positive result is defined as the presence of a cluster of at least two strongly stained epithelial nuclei in the upper two-thirds of the epithelial thickness. With such a definition, there is almost complete concordance between consensus diagnosis of LSIL/condyloma confirmed by detection of HPV DNA and positive Ki-67. A related proliferation marker, ProEx™ C, has similar staining patterns and utility for the diagnosis of low grade dysplasia. The differential diagnosis of HSIL includes atypical immature squamous metaplasia and atrophy. A marker with high sensitivity and specificity for the detection of HSIL in cervical, vulvar, and anal mucosa is p16. A 2-tier scoring system is used to evaluate p16 staining. No staining or a discontinuous, patchy nuclear and cytoplasmic staining pattern is considered as a negative result. A positive result is defined as diffuse and strong staining of cells of the basal and parabasal layers of the squamous epithelium, with or without staining of superficial cell layers. New markers that are undergoing evaluation for their clinical utility include stathmin-1, phosphorylated S6, and SOX2. Confirmation of the diagnosis of dysplasia by HPV detection in tissue sections using HPV capsid protein immunohistochemistry, HPV DNA or HPV RNA in situ hybridization offers lower sensitivity as compared to immunohistochemistry for surrogate markers and therefore has more limited utility in this context.

Human papillomavirus DNA prevalence and type distribution in anal carcinomas worldwide.

Knowledge about human papillomaviruses (HPV) types involved in anal cancers in some world regions is scanty. Here, we describe the HPV DNA prevalence and type distribution in a series of invasive anal cancers and anal intraepithelial neoplasias (AIN) grades 2/3 from 24 countries. We analyzed 43 AIN 2/3 cases and 496 anal cancers diagnosed from 1986 to 2011. After histopathological evaluation of formalin-fixed paraffin-embedded samples, HPV DNA detection and genotyping was performed using SPF-10/DEIA/LiPA25 system (version 1). A subset of 116 cancers was further tested for p16(INK4a) expression, a cellular surrogate marker for HPV-associated transformation. Prevalence ratios were estimated using multivariate Poisson regression with robust variance in the anal cancer data set. HPV DNA was detected in 88.3% of anal cancers (95% confidence interval [CI]: 85.1-91.0%) and in 95.3% of AIN 2/3 (95% CI: 84.2-99.4%). Among cancers, the highest prevalence was observed in warty-basaloid subtype of squamous cell carcinomas, in younger patients and in North American geographical region. There were no statistically significant differences in prevalence by gender. HPV16 was the most frequent HPV type detected in both cancers (80.7%) and AIN 2/3 lesions (75.4%). HPV18 was the second most common type in invasive cancers (3.6%). p16(INK4a) overexpression was found in 95% of HPV DNA-positive anal cancers. In view of the results of HPV DNA and high proportion of p16(INK4a) overexpression, infection by HPV is most likely to be a necessary cause for anal cancers in both men and women. The large contribution of HPV16 reinforces the potential impact of HPV vaccines in the prevention of these lesions.

Diagnosis of HPV-negative, gastric-type adenocarcinoma of the endocervix.

Gastric-type adenocarcinoma of the cervix (GAS) is a novel, recently described subtype of endocervical adenocarcinoma. The clinical importance of accurate diagnosis of GAS stems from the observation that it confers worse prognosis than the usual-type endocervical adenocarcinoma. There are two unique characteristics of GAS: the tumor cells contain voluminous amounts of gastric-type mucins, and the tumor pathogenesis is not related to infection with high-risk human papillomavirus types. The histopathologic diagnosis of GAS is difficult; however, it may be confirmed by demonstration of intra-cytoplasmic gastric-type mucins using immunohistochemical staining with monoclonal antibody HIK1083. A protocol for HIK1083 immunostaining is described.