Automated quantification of stromal tumour infiltrating lymphocytes is associated with prognosis in breast cancer

Stromal tumour infiltrating lymphocytes (sTIL) in haematoxylin and eosin (H&E) stained sections has been linked to better outcomes and better responses to neoadjuvant therapy in triple-negative and HER2-positive breast cancer (TNBC and HER2 +). However, the infiltrate includes different cell populations that have specific roles in the tumour immune microenvironment. Various studies have found high concordance between sTIL visual quantification and computational assessment, but specific data on the individual prognostic impact of plasma cells or lymphocytes within sTIL on patient prognosis is still unknown. In this study, we validated a deep-learning breast cancer sTIL scoring model (smsTIL) based on the segmentation of tumour cells, benign ductal cells, lymphocytes, plasma cells, necrosis, and 'other' cells in whole slide images (WSI). Focusing on HER2 + and TNBC patient samples, we assessed the concordance between sTIL visual scoring and the smsTIL in 130 WSI. Furthermore, we analysed 175 WSI to correlate smsTIL with clinical data and patient outcomes. We found a high correlation between sTIL values scored visually and semi-automatically (R = 0.76; P = 2.2e-16). Patients with higher smsTIL had better overall survival (OS) in TNBC (P = 0.0021). In the TNBC cohort, smsTIL was as an independent prognostic factor for OS. As part of this work, we introduce a new segmentation dataset of H&E-stained WSI.

Detection of variable genotypes in common human papillomavirus-associated invasive penile squamous cell carcinomas: a study of 177 human papillomavirus-positive cases

Human papillomavirus (HPV) is detected in 30-50% of invasive penile carcinomas, and it is frequently associated with basaloid and warty morphological features. Based on this heterogeneity and different clinical behaviors, we hypothesized a variation in their HPV genotypic composition. To test this, we evaluated 177 HPV-positive cases: basaloid (114), warty-basaloid (28), and warty (condylomatous) (35) invasive carcinomas. HPV DNA detection and genotyping was performed using the SPF-10/DEIA/LiPA25 system. Nineteen HPV genotypes were detected. High-risk HPVs predominated (96%), and low-risk HPVs were rarely present. Most common genotype was HPV16 followed by HPVs 33 and 35. According to the genotypes identified, 93% of the cases would be covered with current vaccination programs. There was a significant variation in the distribution of HPV16 and non-HPV16 genotypes according to histological subtype. HPV16 was significantly frequent in basaloid (87%) and was less frequent in warty carcinomas (61%). This molecular difference, along with their distinctive macro-microscopic and prognostic features, makes basaloid and warty carcinomas unique. The gradual decreasing frequency of HPV16 demonstrated in basaloid, warty-basaloid, and warty carcinomas suggest that the basaloid cell, present in those types in decreasing proportions, may be responsible for the differences.

Characterization and spatial distribution of the immune cell infiltrate in triple-negative breast cancer: a novel classification based on plasma cells and CD8+ T cells

Stromal tumor-infiltrating lymphocytes (sTILs) are a robust prognostic and predictive biomarker in triple-negative breast carcinoma. However, the sTIL compartment comprises different cell populations. The aim of the study is to characterize the distribution of T cells (CD3+ and CD8+), B cells, and plasma cells and explore their association with outcome in the surgical specimen of 62 patients. Furthermore, programmed death ligand 1 expression and the presence of tertiary lymphoid structures (TLSs) are explored. Patients with higher sTILs achieve better progression-free survival (PFS) (P = .0013), and tumors have more plasma cells in the infiltrate. Specifically, higher counts of T cells (both CD3+ and CD8+) have better PFS (P = .002 and P = .0086, respectively) as it is observed in tumors with higher infiltration of CD8+ T cells in the tumor core (P = .035). Higher infiltration by B cells and plasma cells shows a positive tendency toward increased PFS (P = .06 and P = .058). Programmed death ligand 1 (SP142) is positive in 56% of tumors. Tumors with at least 1 TLS (42%) show higher CD8+ T cell infiltration in the tumor core and the sTIL value doubles compared to tumors devoid of TLSs [sTIL mean: 36 ± 11% and 18 ± 5% (CI [Confidence Interval]: 95%), respectively]. Our study demonstrates that the characterization of the immune cell infiltration is as relevant as its distribution. Moreover, the importance of considering different immune cell types for classification is emphasized. Therefore, a new classification of triple-negative breast carcinoma immune infiltration with CD8+ T cell and plasma cell densities in the tumor core and infiltrative margin is proposed.

Podocytopathy in patients with monoclonal gammopathy: three patients and literature review

BACKGROUND

Renal manifestations of monoclonal gammopathies are of increasing interest among nephrologists. Typical manifestations include light chain cast nephropathy, amyloidosis or renal damage mediated by monoclonal immunoglobulin deposition. Podocytopathies in the setting of an underlying monoclonal gammopathy constitute a rare manifestation of these diseases and, although being described in the literature, remain a challenge since most data derive from case reports.

METHODS

A retrospective review of the clinical data of Hospital del Mar and Hospital Vall d'Hebron was performed to identify patients with minimal change disease (MCD) or focal and segmental glomerulosclerosis (FSGS) in the setting of neoplasms that produce monoclonal (M) protein. Additionally, a literature review on this topic was performed. This study aims to describe the clinical characteristics and outcomes of these patients.

RESULTS

Three patients were identified to have podocytopathy and monoclonal gammopathy between the years 2013 and 2020. All three were males and  >65 years of age. Two patients were diagnosed with MCD and one patient was diagnosed with FSGS. All patients underwent a kidney biopsy and light and electron microscopic studies were performed. The underlying causes of monoclonal gammopathy were multiple myeloma in two cases and Waldeström macroglobulinemia in one case. Two patients developed nephrotic syndrome during the follow-up. All patients were under active hematological treatment. One patient presented a complete remission of proteinuria whereas the other two presented a partial remission.

CONCLUSIONS

Podocytopathies may infrequently be found in patients with monoclonal gammopathies. Patients with overt glomerular proteinuria and hematological disorders with M protein should undergo a kidney biopsy for prompt diagnosis and to specify a prognosis. In addition, further study on this matter must be done to understand the pathophysiology and treat these patients appropriately.

Long-term protection of HPV test in women at risk of cervical cancer

Objective

To evaluate the 9-year incidence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and cumulative adherence to perform a next test in a cohort of women aged 40+ years with no cervical screening cytology within a window of 5 years (underscreened women), after baseline cervical cytology and HPV tests.

Methods

In Catalonia, Spain, co-testing with cytology and HPV test has been recommended in the Public Health system since 2006 for underscreened women. In 2007, 1,594 women with underscreened criteria were identified and followed through medical records form Pathological Department. 9-year cumulative incidence of histologically confirmed CIN2+ and cumulative adherence to perform a next test were estimated using Kaplan-Meier statistics.

Results

Follow-up was available for 1,009 women (63.3%) resulting in 23 women with. CIN2+ (2.3%). Of them, 4 women (17%) had both tests negative at baseline (3CIN2 and 1CIN3) with cumulative incidence of CIN2+ of 0.4% (95% CI: 0.1–1.4) at 5-years and 1.3% (95% CI: 0.4–3.7) at 9-years. During the first year, the prevalence among women with both tests positive was 27.0% (95% CI: 13.0–50.6) for CIN2+. Lost to follow-up was higher among women with both tests negative compared to those with both positive tests (38.7% vs 4.2%, p-value <0.001). 40.5% of the women HPV-/cyto- had a re-screening test during the 4 years following the baseline, increasing until 53.5% during the 6 years of follow-up.

Conclusions

HPV detection shows a high longitudinal predictive value at 9-year to identify women at risk to develop CIN2+. The data validate a safe extension of the 3-year screening intervals (current screening interval) to 5-year intervals in underscreened women that had negative HPV result at baseline. It is necessary to establish mechanisms to ensure screening participation and adequate follow-up for these women.

Complementary value of electron microscopy and immunohistochemistry in the diagnosis of non-small cell lung cancer: A potential role for electron microscopy in the era of targeted therapy

With the identification of therapeutic targets for lung adenocarcinoma, it has become mandatory to distinguish it from other entities. Some cases remain classified as non-small cell lung carcinoma, not otherwise specified (NSCLC-NOS) with immunohistochemistry. Electron microscopy (EM) can be useful, allowing the identification of glandular differentiation. The aim of this study was to determine the complementary value of immunohistochemistry and EM.Forty-eight NSCLC-NOS cases were selected (PSMAR-Biobank, Barcelona, Spain). Immunohistochemistry (TTF-1, p40) was performed. Tissue was retrieved from paraffin blocks. Results were compared to the final diagnosis, derived from combination of light microscopy, immunohistochemistry, EM, molecular studies and resection specimen.Immunohistochemistry concurred with final diagnosis in 36 cases (75%, Kappa = 0.517). EM agreed with final diagnosis in 35 (72.9%, Kappa = 0.471). Immunohistochemistry had a sensitivity = 73%, specificity = 100%, positive predictive value (PPV) = 100% and negative predictive value (NPV) = 52.4% for adenocarcinoma. All adenocarcinoma cases not solved by immunohistochemistry (n = 10) were classified by EM, and vice versa. Data from EM were identical to those of immunohistochemistry: sensitivity = 73%, specificity = 100%, PPV = 100% and NPV = 52.4%. Combining both techniques, 47 cases were coincident with final diagnosis (97.9%, Kappa = 0.943).EM can provide valuable information in subtyping NSCLC-NOS, being particularly useful when immunohistochemistry is inconclusive. EM could be considered as a complementary tool for decision-making in NSCLC-NOS.

Burden of Human Papillomavirus (HPV)-Related Cancers Attributable to HPVs 6/11/16/18/31/33/45/52 and 58

BACKGROUND

Many countries, mainly high- and upper-middle income, have implemented human papillomavirus (HPV) vaccination programs, with 47 million women receiving the full course of vaccine (three doses) in 2014. To evaluate the potential impact of HPV vaccines in the reduction of HPV-related disease, we aimed to estimate the HPV type distribution and burden of anogenital and head and neck cancers attributable to HPV types (HPVs 16/18/31/33/45/52/58/6/11) included in currently licensed HPV vaccines.

METHODS

In all, 18 247 formalin-fixed paraffin-embedded specimens were retrieved from 50 countries. HPV DNA detection and typing were performed with the SPF-10 PCR/DEIA/LiPA25 system. With the exception of cervical cancer, HPV DNA-positive samples were additionally subjected to HPV E6*I mRNA detection and/or p16INK4a immunohistochemistry. For cervical cancer, estimates were based on HPV DNA, whereas for other sites, estimates were based on HPV DNA, E6*I mRNA, and p16INK4a biomarkers.

RESULTS

The addition of HPVs 31/33/45/52/58 to HPVs 16/18/6/11 in the nonavalent HPV vaccine could prevent almost 90% of cervical cancer cases worldwide. For other sites, the nonavalent HPV vaccine could prevent 22.8% of vulvar, 24.5% of penile, 60.7% of vaginal, 79.0% of anal cancers, 21.3% of oropharyngeal, 4.0% of oral cavity, and 2.7% of laryngeal cancer cases.

CONCLUSIONS

Our estimations suggest a potential impact of the nonavalent HPV vaccine in reducing around 90% of cervical cancer cases and a global reduction of 50% of all the cases at HPV-related cancer sites.

[The Spanish Society of Cytology: Quality control program of gynecological cytology]

INTRODUCTION

In Spain, the guidelines for cervical cancer screening include a recommendation to enroll in external quality control programs. The Spanish Society of Cytology (SEC) has initiated its own quality control program of gynecological cytology (QCPGC).

AIM

To describe and discuss the results of the second round of SEĆs QCPGC.

MATERIAL AND METHOD

The cases are selected by a group of expert cytologists. The cases with an agreement of 75% of four cytopathologists were used. The cases were scanned with Aperio. The scanned cases not available were excluded. We included a total of 23 cases, 1 negative, 15 low grade lesions (4 ASCUS and 11 LSIL) and 7 high grade lesions (1 ASCH and 6 HSIL). Sixteen cases were studied with ThinPrep™ platform and in 7 cases the SurePath™ platform was used.

RESULTS

Sixteen hospitals participated. The global mean concordance was 70.6%. The mean concordance in the type of lesion was 63.1%. The concordance was 71.9% in negative diagnoses, 56.2% in ASCUS, 69.5% in LSIL and 82.8% in HSIL The discordant cases were diagnosed more frequently as negative and ASCUS. 4.4% of cases had major discordances (HSIL or ASCH versus negatives).

CONCLUSIONS

Our results are similar to those reported in the literature, with very few severe discordances.

Role of mucosal high-risk human papillomavirus types in head and neck cancers in central India

Mucosal high-risk (HR) human papillomaviruses (HPV) cause a subset of head and neck cancers (HNC). The HPV-attributable fraction of HNC varies substantially between countries. Although HNC has a very high incidence in the Indian subcontinent, information on the contribution of HPV infection is limited. Here, we evaluated the HPV-attributable fraction in HNC (N = 364) collected in a central region of India. HNC from three different anatomical subsites were included, namely, oral cavity (n = 252), oropharynx (n = 53) and hypopharynx/larynx (n = 59). In this retrospective study, HPV-driven HNC were defined by presence of both viral DNA and RNA. Overexpression of p16INK4a was also evaluated. HR-HPV DNA was detected in 13.7% of the cases; however, only 2.7% were positive for both HPV DNA and RNA. The highest percentage of HPV DNA/RNA double positivity was found in oropharynx (9.4%), followed by larynx (1.7%) and oral cavity (1.6%) (p = 0.02). More than half of HPV DNA/RNA-positive cases were p16INK4a -negative, while a considerable number of HPV RNA-negative cases were p16INK4a -positive (17.9%). HPV16 was the major type associated with HNC (60.0%), although cases positive for HPV18, 35 and 56 were also detected. Our data indicate that the proportion and types of mucosal HR-HPV associated with HNC in this central Indian region differ from those in other (developed) parts of the world. This may be explained by differences in smoking and/or sexual behaviour compared with North America and northern Europe. Moreover, we show that p16INK4a staining appeared not to be a good surrogate marker of HPV transformation in the Indian HNC cases.

Current dilemmas in the diagnosis and management of follicular thyroid tumors

Follicular carcinoma (FTC) is a relatively uncommon type of differentiated thyroid carcinoma. Guidelines have often dealt with FTC and papillary thyroid cancer as a single disease. Over the last decade, however, a better understanding of these two types of thyroid cancer indicates that they cannot be analysed together. Neither ultrasonography nor fine-needle aspiration cytology can provide a clear distinction between FTC and follicular adenoma. New molecular diagnostic techniques may be used to identify a subpopulation of follicular neoplasms with a low probability of being malignant. Diagnostic surgery-usually hemithyroidectomy- is recommended for most thyroid follicular lesions without a certain preoperative diagnosis. If FTC is diagnosed most-perhaps not all- patients will require a completion thyroidectomy. While widely invasive FTC usually does not pose diagnostic or therapeutic doubts, consensus on the diagnosis of non-invasive follicular lesions is still lacking. Prognosis of FTC is mostly dependent on local invasion and distant metastasis that, in turn, correlate with tumor size.

Self-sampling versus physician-sampling for human papillomavirus testing

We evaluated the detection of human papillomavirus (HPV) infection using two sampling methods of cervical exfoliated cells, consisting of self-sampling of vaginal cells and cervical sampling performed by the physician. Women included were 379 patients of the general population attending outpatient clinics in Northern Greece for routine cytological cervical dysplasia screening. HPV DNA detection was similar with both sampling techniques. The HPV prevalences in self-collected samples were 4.7% and 3.7% in the physician-collected samples ( P>0.05). The Kappa statistic for HPV DNA agreement between the two methods was 0.54 (95% Confidence interval = 0.33–0.75). Self-sampling of cervico-vaginal exfoliated cells could be used as an alternative option to test for HPV infection.

Role of Human Papillomavirus in Penile Carcinomas Worldwide

BACKGROUND

Invasive penile cancer is a rare disease with an approximately 22 000 cases per year. The incidence is higher in less developed countries, where penile cancer can account for up to 10% of cancers among men in some parts of Africa, South America, and Asia.

OBJECTIVE

To describe the human papillomavirus (HPV) DNA prevalence, HPV type distribution, and detection of markers of viral activity (ie, E6*I mRNA and p16(INK4a)) in a series of invasive penile cancers and penile high-grade squamous intraepithelial lesions (HGSILs) from 25 countries. A total of 85 penile HGSILs and 1010 penile invasive cancers diagnosed from 1983 to 2011 were included.

DESIGN, SETTING, AND PARTICIPANTS

After histopathologic evaluation of formalin-fixed paraffin-embedded samples, HPV DNA detection and genotyping were performed using the SPF-10/DEIA/LiPA25 system, v.1 (Laboratory Biomedical Products, Rijswijk, The Netherlands). HPV DNA-positive cases were additionally tested for oncogene E6*I mRNA and all cases for p16(INK4a) expression, a surrogate marker of oncogenic HPV activity.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

HPV DNA prevalence and type distributions were estimated.

RESULTS AND LIMITATIONS

HPV DNA was detected in 33.1% of penile cancers (95% confidence interval [CI], 30.2-36.1) and in 87.1% of HGSILs (95% CI, 78.0-93.4). The warty-basaloid histologic subtype showed the highest HPV DNA prevalence. Among cancers, statistically significant differences in prevalence were observed only by geographic region and not by period or by age at diagnosis. HPV16 was the most frequent HPV type detected in both HPV-positive cancers (68.7%) and HGSILs (79.6%). HPV6 was the second most common type in invasive cancers (3.7%). The p16(INK4a) upregulation and mRNA detection in addition to HPV DNA positivity were observed in 69.3% of HGSILs, and at least one of these HPV activity markers was detected in 85.3% of cases. In penile cancers, these figures were 22.0% and 27.1%, respectively.

CONCLUSIONS

About a third to a fourth of penile cancers were related to HPV when considering HPV DNA detection alone or adding an HPV activity marker, respectively. The observed HPV type distribution reinforces the potential benefit of current and new HPV vaccines in the reduction of HPV-related penile neoplastic lesions.

PATIENT SUMMARY

About one-third to one-quarter of penile cancers were related to human papillomavirus (HPV). The observed HPV type distribution reinforces the potential benefit of current and new HPV vaccines to prevent HPV-related penile neoplastic lesions.

Urine human papillomavirus prevalence in women with high-grade cervical lesions

OBJECTIVE

To determine the prevalence of human papillomavirus (HPV) in urine samples from women with high-grade cervical lesions. Secondary objectives are to identify the influence of socio-demographic factors and the different genotypes with urinary HPV positivity.

STUDY DESIGN

75 women with a positive biopsy for CIN2+ were included in the study from October 2010 to July 2011. A sample of urine was collected immediately before conization at the outpatient clinic. We analyzed the presence of HPV using a PCR technique.

RESULTS

The mean age of the patients was 34.8 years (range 24 to 61). All patients had histological CIN2+, of whom 54.67% had CIN3. The prevalence of HPV in urine test was 58.82% in CIN2 population versus 78.05% in CIN3 patients (p 0.072). 31 different genotypes were found. The most frequent HPV genotype was 16-HPV, which was identified in 58% of women with positive HPV-DNA in urine samples. No demographic characteristics were significantly associated to urinary HPV prevalence.

CONCLUSION

Most of the patients with CIN2+ showed positive results for urine HPV test. The prevalence of positive urinary HPV test was higher for patients with CIN3. HPV urine detection could be considered as an acceptable option for high-risk population who skip regular screening programs.

Human beta papillomavirus DNA study in primary cutaneous squamous cell carcinomas and their corresponding metastases

The association between beta human papillomavirus (HPV) types and cutaneous squamous cell carcinomas (cSCCs) is controversial. Several studies have found such an association, especially at early stages of carcinogenesis, but the presence of beta HPV types in aggressive cSCCs has only been reported in three patients previously. We aimed to search for beta HPV DNA in primary cSCCs and their corresponding lymph node metastases in a series of patients. The presence of DNA from 25 beta HPV types was determined using a multiplex PCR protocol in 35 primary cSCCs from 35 patients and their corresponding lymph node metastases. DNA from beta HPV types was detected in 9 % of primary cSCCs and in 13 % of metastases. No primary cutaneous SCC or lymphatic metastases were found to share the same HPV DNA. These data suggest that beta HPV types do not play an etiopathogenic role in advanced stages of squamous cell carcinogenesis.

Worldwide human papillomavirus genotype attribution in over 2000 cases of intraepithelial and invasive lesions of the vulva

BACKGROUND

Human papillomavirus (HPV) contribution in vulvar intraepithelial lesions (VIN) and invasive vulvar cancer (IVC) is not clearly established. This study provides novel data on HPV markers in a large series of VIN and IVC lesions.

METHODS

Histologically confirmed VIN and IVC from 39 countries were assembled at the Catalan Institute of Oncology (ICO). HPV-DNA detection was done by polymerase chain reaction using SPF-10 broad-spectrum primers and genotyping by reverse hybridisation line probe assay (LiPA25) (version 1). IVC cases were tested for p16(INK4a) by immunohistochemistry (CINtec histology kit, ROCHE). An IVC was considered HPV driven if both HPV-DNA and p16(INK4a) overexpression were observed simultaneously. Data analyses included algorithms allocating multiple infections to calculate type-specific contribution and logistic regression models to estimate adjusted prevalence (AP) and its 95% confidence intervals (CI).

RESULTS

Of 2296 cases, 587 were VIN and 1709 IVC. HPV-DNA was detected in 86.7% and 28.6% of the cases respectively. Amongst IVC cases, 25.1% were both HPV-DNA and p16(INK4a) positive. IVC cases were largely keratinising squamous cell carcinoma (KSCC) (N=1234). Overall prevalence of HPV related IVC cases was highest in younger women for any histological subtype. SCC with warty or basaloid features (SCC_WB) (N=326) were more likely to be HPV and p16(INK4a) positive (AP=69.5%, CI=63.6-74.8) versus KSCC (AP=11.5%, CI=9.7-13.5). HPV 16 was the commonest type (72.5%) followed by HPV 33 (6.5%) and HPV 18 (4.6%). Enrichment from VIN to IVC was significantly high for HPV 45 (8.5-fold).

CONCLUSION

Combined data from HPV-DNA and p16(INK4a) testing are likely to represent a closer estimate of the real fraction of IVC induced by HPV. Our results indicate that HPV contribution in invasive vulvar cancer has probably been overestimated. HPV 16 remains the major player worldwide.

Biological evidence for a causal role of HPV16 in a small fraction of laryngeal squamous cell carcinoma

BACKGROUND

Human papillomavirus (HPV) is a causal factor in virtually all cervical and a subset of oropharyngeal squamous cell carcinoma (OP-SCC), whereas its role in laryngeal squamous cell carcinoma (L-SCC) is unclear.

METHODS

Formalin-fixed paraffin-embedded (N=154) and deep-frozen tissues (N=55) of 102 L-SCC patients were analysed for the presence of 51 mucosal HPV types. HPV DNA-positive (HPV DNA+) cases were analysed for E6*I mRNA transcripts of all high risk (HR)/probably/possibly (p)HR-HPV identified, and for HPV type 16 (HPV16) viral load. Expression of p16(INK4a), pRb, cyclin D1 and p53 was analysed by immunohistochemistry.

RESULTS

Ninety-two patients were valid in DNA analysis, of which 32 (35%) had at least one HPV DNA+ sample. Among the 29 single infections, 22 (76%) were HPV16, 2 (7%) HPV56 and 1 each (4%) HPV45, HPV53, HPV70, HPV11 and HPV42. Three cases harboured HPV16 with HPV33 (twice) or HPV45. Only 32% of HPV DNA+ findings were reproducible. Among HPV16 DNA+ L-SCC, 2 out of 23 (9%) had high viral loads, 5 out of 25 (21%) expressed E6*I mRNA and 3 out of 21 (14%) showed high p16(INK4a) and low pRb expression (all three HPV16 RNA-positive), immunohistochemical marker combination not identified in any other HPV DNA+ or HPV DNA-negative (HPV DNA-) L-SCC, respectively.

CONCLUSION

HPV type 16 has a causative role in a small subgroup of L-SCC (<5% in this German hospital series).

HPV testing by cobas HPV test in a population from Catalonia

Background

HPV testing in cervical cancer screening has been proposed as an alternative or complementary to cytology in women older than 30 years. However, adequate clinical sensitivity and specificity are crucial for a new test to be implemented. Hybrid Capture 2 (HC2) has proved good clinical performance in selecting women at risk for high-grade intraepithelial lesions with a high sensitivity and specificity. cobas HPV Test has been recently launched and its performance in different clinical settings needs to be determined.

Objectives

The aim of this study was to evaluate the cobas HPV Test for the detection of cervical HPV infection in a population of women in Catalonia (Spain) using HC2 as a reference.

Materials and Methods

Cervical liquid cytology samples from 958 women have been studied. Sensitivity was analyzed in 60 samples from patients with a high-grade intraepithelial lesion (≥CIN2) on histology and specificity was determined in 898 samples from women with no ≥CIN2. All cases had HC2 and cobas HPV Test performed. Statistical analyses of sensitivity, specificity and comparison between HC2 and cobas HPV Test by a non-inferiority test were applied.

Results

Sensitivity of HC2 and cobas HPV Test for detecting ≥CIN2 proved identical (98.3%) while specificity was 85.3% and 86.2% respectively. The non-inferiority test demonstrated that cobas HPV Test surpassed 90% sensitivity and 98% specificity of HC2.

Conclusion

The cobas HPV Test results fulfilled sensitivity and specificity requirements for HPV based cervical cancer screening and for the triage of minor cytological abnormalities, allowing its introduction in clinical settings.

A humanized mouse model of HPV-associated pathology driven by E7 expression

Human papillomavirus (HPV) is the causative agent of human cervical cancer and has been associated with oropharyngeal squamous cell carcinoma development. Although prophylactic vaccines have been developed, there is a need to develop new targeted therapies for individuals affected with malignant infected lesions in these locations, which must be tested in appropriate models. Cutaneous beta HPV types appear to be involved in skin carcinogenesis. Virus oncogenicity is partly achieved by inactivation of retinoblastoma protein family members by the viral E7 gene. Here we show that the E7 protein of cutaneous beta HPV5 binds pRb and promotes its degradation. In addition, we described an in vivo model of HPV-associated disease in which artificial human skin prepared using primary keratinocytes engineered to express the E7 protein is engrafted onto nude mice. Expression of E7 in the transplants was stably maintained for up to 6 months, inducing the appearance of lesions that, in the case of HPV16 E7, histologically resembled human anogenital lesions caused by oncogenic HPVs. Moreover, it was confirmed through biomarker expression analysis via immunodetection and/or quantitative PCR from mRNA and miRNA that the 16E7-modified engrafted skin shares molecular features with human HPV-associated pretumoral and tumoral lesions. Finally, our findings indicate a decrease of the in vitro capacity of HPV5 E7 to reduce pRb levels in vivo, possibly explaining the phenotypical differences when compared with 16E7-grafts. Our model seems to be a valuable platform for basic research into HPV oncogenesis and preclinical testing of HPV-associated antitumor therapies.

PCR study of a series of ASCUS cases HPV-positive by HCII

Most guidelines currently recommend the testing of human papillomavirus (HPV) in ASCUS cases. The most used method for this purpose is Hybrid Capture II (HCII), but PCR techniques with GP5+/6+ primers can be also applied. Furthermore, the HCII high-risk probe test for detection of HPV shows cross-reactivity with low-risk HPV. Although this cross-reactivity has been studied in screening populations, it has received little attention in ASCUS cases. To compare the performance of the HCII high-risk probe test and PCR for the detection of HPV in ASCUS cases. We randomly selected 83 ASCUS cases that were positive for high-risk HPV by HCII and applied the PCR test using MYO9-11 and GP5+/6+ primers to samples from these cases. Our results show cross-reactivity with low-risk HPV in 25.3% (21/83) of the HCII+ PCR+ cases. Regarding the follow-up our results emphasize the importance of HPV typing, especially for HPV 16 infection. We propose the use of PCR techniques using GP5+/6+ consensus primers for the screening of HPV in ASCUS.

Human papillomavirus prevalence and type-specific relative contribution in invasive cervical cancer specimens from Italy

BACKGROUND

Cervical cancer represents an important global public health problem. It is the 2nd most common cancer among women worldwide. Human papillomavirus (HPV) infection is now well-established as a necessary cause of invasive cervical cancer (ICC) development. Only a few studies on HPV prevalence and type-specific distribution in ICC have been conducted in Italy.

AIM

To describe the prevalence of HPV and the HPV type-specific distribution in ICC cases identified in Rome, Italy.

METHODS

140 paraffin embedded tissue blocks of primary ICC diagnosed between 2001 and 2006 were identified at the Regina Elena Cancer Institute in Rome (Italy). HPV was detected through amplification of HPV DNA using SPF-10 HPV broad-spectrum primers followed by DEIA and then genotyping by LiPA25 (version 1).

RESULTS

134 cases were considered suitable for HPV DNA detection after histological evaluation; and overall, 90.3% (121/134) HPV prevalence was detected. 111 cases had a single HPV type, 4 cases had an uncharacterized type (HPVX) and 6 cases had multiple HPV infections. The five most common single HPV types among positive cases were: HPV16 (71/121; 58.7%), HPV18 (12/121; 9.9%), HPV31, HPV45 and HPV58 (5/121; 4.1% each). 2 (1.5%) of the single infections and 2 (1.5%) of the multiple infections contained low risk types. Statistically significant differences in the relative contribution of HPV18 were found when comparing squamous cell carcinomas with adenocarcinomas.

CONCLUSIONS

HPV16 and HPV18 accounted for almost 70% of all the HPV positive ICC cases. The study provides baseline information for further evaluation on the impact of recently introduced HPV vaccines in Italy.

High prevalence of human papillomavirus infection in the female population of Guatemala

The potential introduction of the newly licensed HPV-vaccines at affordable prices could play a central role in preventing cervical cancer in middle and low-income countries, where most of the cases occur. In spite of this, basic epidemiological data about HPV and HPV-related lesions are still scarce. To determine the prevalence of cervical abnormalities, HPV prevalence, genotype distribution and related risk factors, we carried out a cross-sectional study in a population from Guatemala that included 297 women from the general population (GP women) and 297 sex workers (SW). All participating women were interviewed and underwent a complete gynecological examination that included collection of cervical cells for cytological diagnosis, HPV DNA detection and typing by PCR methods. Cervical HPV DNA prevalence among GP women and from SW was 38.1% (95% CI: 32.5-43.8) and 67.3% (95% CI: 61.7-72.6), respectively. The prevalence of abnormal cytology among GP women was 7.7% (ASCUS = 1.4%, LSIL = 4.7%, ASC-H = 0.3% and HSIL = 1.4%) and among SW was 21.6% (ASCUS = 7.5%, LSIL = 10.6%, ASC-H = 1.4% and HSIL = 2.1%). The most prevalent HPV types among women with normal cytology were HPVs 51 (n = 30), 66 (n = 25) and 16 (n = 25), and among women with HSIL or ASC-H (n = 14) HPVs 58 (n = 5) and 16 (n = 5). Determinants associated with HPV DNA detection were having had an occasional partner during the last 6 months and smoking habit among GP women, and being a minor among SW. HPV and abnormal cytology prevalence is high among women in Guatemala. The introduction of a HPV vaccination program would prevent an important fraction of HPV-related disease burden.

3q26 (hTERC) gain studied by fluorescence in situ hybridization as a persistence-progression indicator in low-grade squamous intraepithelial lesion cases

Gains of 3q26 chromosome region, where the human telomerase RNA gene (hTERC) is located, have been previously documented in cervical carcinomas and preneoplastic lesions. The aim of our study was to define the value of 3q26 gains related to persistence-progression in cervical specimens with cytologic diagnosis for low-grade squamous intraepithelial lesions, using liquid-based cytology (ThinPrep; Hologic, Marlborough, MA) and fluorescence in situ hybridization. For these purposes, 55 patients were included in the study: 25 cases with a negative cytologic diagnosis for squamous intraepithelial lesion or malignancy (20 premenopausal and 5 postmenopausal women, used as control negative cases) and 30 low-grade squamous intraepithelial lesion cases. The follow-up was performed using cytology at 6, 12, and 24 months after the low-grade squamous intraepithelial lesion diagnosis. When the cytology result showed a high-grade lesion, colposcopy and biopsy were performed. Fluorescence in situ hybridization technique with a 3q26 2-color commercial probe was performed to determine the number of hTERC copies. There were no differences between premenopausal and postmenopausal normal cases. Low-grade squamous intraepithelial lesion cases with regression in the follow-up at 6, 12, and 24 months showed a percentage of cells with 3q26 gains similar to the control cases and lower than low-grade squamous intraepithelial lesion cases with persistence or progression (P < .05). Fluorescence in situ hybridization results were similar in preserved and frozen samples. However, in frozen samples, the number of cells suitable to be evaluated by fluorescence in situ hybridization was lower than in preserved (nonfrozen) cases. In conclusion, the determination by fluorescence in situ hybridization of 3q26 gains in low-grade squamous intraepithelial lesion cases could be useful to predict the persistence-progression of such cervical lesions using both preserved and frozen cervical material.

[Assessment of HPV detection assays for use in cervical cancer screening programs]

OBJECTIVE

Detection of high-risk human papillomavirus types (HPV) infection is an important tool in the screening of cervical cancer and triage of cytological abnormalities. The different techniques for detection of this cancer need to be contrasted and validated for use in population screening.

MATERIAL AND METHODS

Cervical cell samples were collected from 166 women attending a dermatology clinic in Oviedo (Spain). We evaluated the performance of three different assays for VPH detection. The methods utilized were 1) In-house PCR-EIA using LI consensus primers MY09/ MY11, 2) A PCR-reverse line blot hybridization (PCR-LBH) that uses LI consensus PGMY primers. 3) Hybrid Capture 2. All assays were performed blinded. The kappa statistic was used to test for global agreement between assay pairs.

RESULTS

HPV DNA was detected in 24,7%, 25,3% and 29,5% of the women, respective to the assay. The overall agreement between the in-house PCR, PCR-LBH and HC2 was (73.5%) with all kappa values between assay pairs exceeding 0.56 (p<0.001).

CONCLUSION

The three HPV assays were equally accurate in estimating high-risk HPV prevalence and HPV-related lesions. The method for HPV detection must be decided depending on the goals of the search (screening, follow-up or molecular studies).

Human papillomavirus testing for primary screening in women at low risk of developing cervical cancer. The Greek experience

OBJECTIVE

To compare the performance of human papillomavirus (HPV) DNA detection against routine Papanicolaou smear for the detection of low- and high-grade cervical intraepithelial neoplasia in a low-risk population.

MATERIALS AND METHODS

A cross-sectional study was performed involving 1296 women attending six outpatient clinics in Northern Greece (Thessaloniki, Thermi, Mihaniona, Corfu, Veria, and Serres). Women underwent a gynecological examination, including collection of exfoliated cervical cells for Papanicolaou cytology and HPV DNA detection. Cytology was processed according the conventional routine manner, and HPV DNA was determined using the polymerase chain reaction technique. In positive cases of either method, a complete colposcopic evaluation was performed with directed biopsies. Tests (HPV DNA, cytology, and colposcopy) performance characteristics were determined using the histopathologic diagnosis as the reference standard.

RESULTS

HPV DNA testing showed a significantly better sensitivity than the Papanicolaou smear in detecting cervical intraepithelial neoplasia (75% versus 50% for high-grade lesions and 81.2% versus 50% for lesions of any grade, respectively). Specificity, and positive and negative predictive values did not significantly differ. Even after dividing women in younger or older than 30 years, the sensitivity of the HPV DNA test was greater than cytology (100% and 70% versus 50% for cytology in both groups, respectively), with a 6.3% loss in specificity when performed in women younger than 30 years.

CONCLUSION

HPV testing could be useful in screening women at low risk for cervical cancer, either as an adjunct tool to augment existing cytology programs or as a unique test of its own.

Cervical human papillomavirus infection in women attending gynaecological outpatient clinics in northern Greece

Human papillomavirus (HPV) is the necessary cause for the development of invasive cervical cancer. Identification of HPV determinants may contribute to the targeting of high-risk groups for cervical cancer. The study was aimed at estimating HPV prevalence and its determinants among 1296 women attending six gynaecological outpatient clinics in northern Greece. Information was available through personal interview and the study of cervical exfoliated cells. HPV DNA was detected by reverse line-blot polymerase chain reaction using the L1 primers PGMY09/11. The overall HPV prevalence was 2.5%. After controlling for potential confounders, the two independent risk factors associated with an increased prevalence were young age and parity. The prevalence odds ratio (POR) for those younger than 27 years against those older than 42 years was 5.31 (95% confidence interval (CI)=1.53-18.44) and the POR for nulliparous women compared with women with two or more children was 4.15 (95% CI=1.35-12.76). HPV was present in 10 of 12 women with low-grade cervical intraepithelial lesions (CIN) (83.3%) and in 3 of 4 with high-grade CIN (75%). The prevalence of genital HPV infections in the study population was among the lowest ever reported internationally.

Apoptosis in ductal carcinoma in situ of the breast

Programmed cell death (apoptosis) may play a role in tumor development and progression. The importance of apoptosis dysregulations in ductal carcinoma in situ (DCIS) and its relationships with p53 mutations and expression of bcl-2 has received little attention in the literature. In a series of 58 DCIS patients, we evaluated the number of apoptotic cells by the TUNEL technique in subgroups of DCIS and correlated it with immunohistochemical expression of hormone receptors, c-erbB-2, p53, bcl-2, and Ki-67 (MIB-1) and DNA content measured by image cytometry. High apoptotic index (greater than 3%) was related to high tumor grade, negative hormone receptors, c-erbB-2 overexpression, aneuploidy and lack of bcl-2 immunohistochemical stain. Apoptosis was not related to p53 or proliferative index. The findings are similar to those found in infiltrating breast cancer.

Human papillomavirus genotypes in rural Mozambique

We studied the genotype distribution of cervical human papillomavirus (HPV) infections in an age-stratified sample of 262 women in Mozambique using the PGMYO9-PGMY11 primer system in a reverse line-blot strip-based assay with high sensitivity in type-specific amplification. Despite the low precision of the estimates, we found that HPV-16 was not the dominant type. Instead, HPV 35 was the most commonly identified genotype among HPV-positive women (16/96 [17%]) and women with cervical neoplasia (7/23 [30%]). Certain genotypes might have been under-detected in previous studies, and type-specific HPV distributions might vary across populations. Therefore, the estimated proportion of cervical neoplasia that could be prevented by an HPV-16-based vaccine could be lower than expected.

Apoptosis in ductal carcinoma in situ of the breast

Programmed cell death (apoptosis) may play a role in tumor development and progression. The importance of apoptosis dysregulations in ductal carcinoma in situ (DCIS) and its relationships with p53 mutations and expression of bcl-2 has received little attention in the literature. In a series of 58 DCIS patients, we evaluated the number of apoptotic cells by the TUNEL technique in subgroups of DCIS and correlated it with immunohistochemical expression of hormone receptors, c-erbB-2, p53, bcl-2, and Ki-67 (MIB-1) and DNA content measured by image cytometry. High apoptotic index (greater than 3%) was related to high tumor grade, negative hormone receptors, c-erbB-2 overexpression, aneuploidy and lack of bcl-2 immunohistochemical stain. Apoptosis was not related to p53 or proliferative index. The findings are similar to those found in infiltrating breast cancer.

[Human papillomavirus and human immunodeficiency virus infections as risk factors for cervix cancer in women prisoners]

BACKGROUND

The identification of high risk groups for genital human papillomavirus (HPV) infection may contribute to cervical cancer prevention. The study was designed to estimate the prevalence of HPV infection and the related risk of cervical cancer among imprisoned women.

PATIENTS AND METHODS

157 women were visited at the Medical Office of a prison in Barcelona, Spain. Women underwent a structured interview, determination of HIV serostatus and detection of HPV cervical infection by means of PCR.

RESULTS

The prevalence of HPV infection was 46%. Prostitution was reported by 38.2% and intravenous drug use by 64.3%. HIV infection was detected in 56.1%. Cervical cytology revealed 19 women with ASCUS and 28 with squamous intraepithelial lesions (SIL) (all grades). HPV infection was associated with an increased risk of intravenous drug use for more than 10 years (prevalence odds ratio [POR] = 2.9) and seropositivity to HIV (POR = 4.7). The increase in risk for SIL related to HIV was explained by the presence of HPV. HIV positive women with low CD4 counts may increase the risk for SIL independently of HPV.

CONCLUSION

HIV positive women are at high risk for HPV infection and as a consequence, for developing SIL. HIV positive women should be closely monitored for cervical cancer.

Circulating HER2 extracellular domain and resistance to chemotherapy in advanced breast cancer

To test the hypothesis of an association between HER2 and chemotherapy resistance, we performed a prospective assessment of the predictive value of the circulating HER2 extracellular domain (ECD) in patients with advanced breast carcinoma in the setting of a multicenter Phase II trial using paclitaxel and doxorubicin. Serum samples were collected from 58 patients with metastatic breast carcinoma before first-line chemotherapy for advanced disease, and the levels of circulating HER2 ECD were measured using an enzyme immunoassay. Immunohistochemistry with anti-HER2 monoclonal antibody CB11 was used to assess the overexpression of HER2 in the primary tumors. When 450 fmol/ml was used as a cutoff, 24 cases (41%) had elevated HER2 ECD levels. Elevated levels of circulating HER2 ECD were associated with the expression of HER2 in the primary tumor tissue and with the metastatic tumor burden (evaluated with the marker CA 15-3; P = 0.032 and P = 0.002, respectively) but not with variables such as menopausal status, stage at diagnosis, previous adjuvant therapy, or the number of metastatic sites. The levels of circulating HER2 ECD correlated inversely with the response to treatment. The probability of obtaining a complete response to chemotherapy was significantly lower (P = 0.021) in patients with elevated HER2 ECD levels (0%; 95% confidence interval, 0-13%) compared with patients with nonelevated HER2 (26%; 95% confidence interval, 12-45%). In addition, the duration of clinical response was significantly shorter in patients with elevated HER2 ECD, compared with the cases with nonelevated HER2 (7.5 versus 11 months; P = 0.035). In conclusion, elevated levels of circulating HER2 ECD in patients with metastatic breast cancer correlate with reduced efficacy of a paclitaxel-doxorubicin chemotherapy combination. We suggest that the poor response rate associated with HER2 expression in advanced breast cancer may not be reversed by aggressive chemotherapy alone.

Bcl-2 with loss of apoptosis allows accumulation of genetic alterations: a pathway to metastatic progression in human breast cancer

We have examined whether the extended life span of cells induced by Bcl-2 in T(1) ductal breast carcinomas might favor the acquisition and accumulation of genetic alterations that induce lymph node metastases. We analyzed the expression of c-Myc, c-erbB-2 and epidermal growth factor receptor by immuno-histochemistry in a group of 142 T(1) (<2 cm) ductal breast carcinomas embedded in paraffin, previously studied for p53 mutation and Bcl-2 over-expression. We also measured the apoptotic status and estimated the excess risk (pOR) for lymph node metastasis according to the number of accumulated oncogene alterations and Bcl-2 and p53 expression. The linear relationship between number of oncogene alterations and presence of lymph node metastasis was statistically significant in Bcl-2-positive tumors (trend test, p = 0.03), p53-mutated tumors (trend test, p = 0.08) and tumors with loss of apoptosis (trend test, p = 0.08). Very large associations (pOR > 12) between the number of oncogene alterations and lymph node metastasis were observed among Bcl-2-positive tumors that showed increased loss of apoptosis (trend test, p = 0.03). Furthermore, in p53-negative tumors, a strong linear association was found between the number of oncogene alterations and risk of lymph node metastasis among Bcl-2-positive tumors (trend test, p = 0.03). In human T(1) ductal breast carcinoma, over-expression of Bcl-2 along with loss of apoptosis might render breast cancer cells susceptible to the acquisition of additional genetic lesions related to disease progression among p53-negative tumors. Thus, in breast cancer, there are at least 2 pathways to progression: Bcl-2- and p53-dependent mechanisms.

[Detection of human papillomavirus DNA by PCR in high-risk women. Validation of a protocol]

OBJECTIVE

To validate a protocol for HPV DNA detection using PCR (polymerase chain reaction).

METHOD

HPV was investigated in cervical exfoliative specimens from 93 women at high risk for HPV infection Blind comparisons of HPV DNA detection using two PCR protocols were carried out in our laboratory and a widely accepted reference laboratory.

RESULTS

HPV DNA prevalence varied according to the different protocols. A good agreement with the reference protocol was reached when a reduction of the cellular amount for DNA extraction was carried out. The prevalence of HPV DNA in this population was 50.5%. All cases with dysplasia were HPV DNA positive. The HPV type distribution was as follows: 29.8% HPV 16, 17% HPV 33, 12.7% HPV 11/6, 12.7%, HPV 18, 23.4% HPV 31, 3.6% HPV 39 y 4.3% HPV 51. An underestimation of the prevalence of HPV 51 was detected by our procedure in relation to the reference laboratory.

CONCLUSIONS

HPV DNA detection by PCR may increase with simple protocol modifications. Regular validation studies are important to reach good sensitivity levels.

Ductal carcinoma in situ of the breast: correlation between histologic classifications and biologic markers

The expression of hormone receptors (estrogen and progesterone), c-erb-B2 (neu), p53, and Ki-67) was studied by immunohistochemical analysis in a series of 94 carcinomas in situ of the breast. The tumors were classified in two (high grade vs. low grade) and three (high grade vs. intermediate grade vs. low grade) categories. High-grade carcinomas were well defined by biologic markers showing statistically significant differences for all of the parameters tested. No clear biologic distinction, however, between low-grade and intermediate-grade cancers could be obtained. Negative progesterone receptors and a high proliferative index are the best discriminant parameters for the final assignment of doubtful cases.

Apoptosis loss and bcl-2 expression: key determinants of lymph node metastases in T1 breast cancer

The Bcl-2 proto-oncogene extends cell survival but does not confer any proliferative advantage to cells that express it. Thus, the loss of apoptosis may have a role in progression allowing the acquisition of additional mutations. To determine whether apoptosis loss at diagnosis is associated with the metastatic advantage of ductal breast carcinomas and to examine the relationship between Bcl-2 expression, p53, and tumor cell death status, we examined tumor samples from 116 patients diagnosed with T1 (2 cm or less) breast cancer with (n = 49) or without (n = 67) lymph node metastases. Apoptosis loss in histological sections was considered when <1% of tumor nuclei were stained with terminal deoxynucleotidyl transferase labeled with biotin. We studied the expression of Bcl-2 and p53 by immunohistochemistry and in 37 p53 mutations by single-strand conformational polymorphism analysis and cycle sequencing. Multivariate logistic regression modeling was used to estimate prevalence odds ratios (pORs) for apoptosis loss and presence of lymph node metastases. Patients with marked apoptosis loss in their tumor cells were about 5 times more likely to present lymph node metastases than those with no apoptosis loss in their tumor cells (adjusted pOR, 4.7; 95% confidence interval, 1.4-15.6; trend test, P = 0.008). Bcl-2 expression was strongly associated with both apoptosis loss (pOR, 6.9; trend test, P < 0.0001) and presence of lymph node metastases (pOR, 5.7; trend test, P = 0.002). These associations were more evident in histological grade I and II tumors than in poorly differentiated histological grade III tumors and in p53-negative tumors than in p53-positive tumors. This study demonstrates for the first time that the lymphatic progression of T1 human breast cancer is strongly related to apoptosis loss.

Bcl-2 expression is associated with lymph node metastasis in human ductal breast carcinoma

The Bcl-2 proto-oncogene product blocks apoptosis. We retrospectively studied Bcl-2 expression in 124 primary tumors from patients diagnosed with T1 (2 cm or less) breast carcinoma with (T1N1) or without (T1N0) lymph-node metastasis. Bcl-2 protein was detected by immunohistochemistry on paraffin-embedded tissue sections. Multivariate logistic regression modeling was used to estimate prevalence odds ratios for lymph-node metastasis. Bcl-2 was widely expressed among T1 tumors showing a strong positive relationship with estrogen (ER)- and progesterone (PR)-receptor-positive tumors. However, a significant inverse correlation was seen between Bcl-2 expression and histological grade, Bcl-2 being absent in the majority of T1 undifferentiated tumors (grade-III carcinomas). Furthermore, Bcl-2 was more frequently expressed in T1N1 cases (72.2%) than in T1N0 specimens (45.7%). The odds for lymph-node metastasis in the Bcl-2-positive group was 3.6 times larger than that in the Bcl-2-negative group. The co-expression of PR significantly modified the effect of Bcl-2 on the odds for lymph-node metastasis, suggesting the existence of a synergistic interaction between the 2 parameters. We studied the percentage of dead cells in primary tumors by in situ DNA fragmentation (FDNA), and found an inverse correlation between Bcl-2 expression and FDNA. This supported the hypothesis that Bcl-2 extends cell survival. In conclusion, our study provides evidence that Bcl-2 expression is involved in breast-cancer progression, at least in a subset of well-differentiated and PR-positive tumors.

In vitro bromodeoxyuridine labeling of malignant neoplasms. A comparative study with flow cytometry cell-cycle analysis

Proliferative fraction has been defined as an independent prognostic marker for some malignant neoplasms. An estimate of the proliferative fraction can be obtained by cell-cycle analysis of flow cytometric DNA measurements. However, overlapping DNA distributions of aneuploid neoplasms are difficult to analyze, even with sophisticated computer programs, and results are not always reproducible. Bromodeoxyuridine (BrdUrd) labeling followed by immunohistochemical detection has been proposed as an alternative, simple, and accurate method for identifying and counting DNA synthesizing cells. In vitro BrdUrd labeling was performed on 87 tumors, including 35 lung cancers, 25 breast carcinomas, and 27 tumors of other origin. Results were compared with flow cytometric S-phase estimates in 46 cases. Mean BrdUrd labeling of lung tumors was 8.5% +/- 5.2%, compared with a mean flow cytometric S-phase fraction of 20% +/- 18.4%. Mean BrdUrd labeling of breast carcinomas was 6.8% +/- 3.8%, compared with a mean flow cytometric S-phase fraction of 12.5% +/- 9.9%. In both tumor types, BrdUrd labeling correlated well with histologic grade. Correlation between BrdUrd labeling and flow cytometric S-phase estimates were generally poor, particularly with aneuploid tumors.