Annabelle Farnsworth

Accuracy of reading liquid based cytology slides using the ThinPrep Imager compared with conventional cytology: prospective study

Objective To compare the accuracy of liquid based cytology using the computerised ThinPrep Imager with that of manually read conventional cytology. Design Prospective study. Setting Pathology laboratory in Sydney, Australia. Participants 55 164 split sample pairs (liquid based sample collected after conventional sample from one collection) from consecutive samples of women choosing both types of cytology and whose specimens were examined between August 2004 and June 2005. Main outcome measures Primary outcome was accuracy of slides for detecting squamous lesions. Secondary outcomes were rate of unsatisfactory slides, distribution of squamous cytological classifications, and accuracy of detecting glandular lesions. Results Fewer unsatisfactory slides were found for imager read cytology than for conventional cytology (1.8% v 3.1%; P<0.001). More slides were classified as abnormal by imager read cytology (7.4% v 6.0% overall and 2.8% v 2.2% for cervical intraepithelial neoplasia of grade 1 or higher). Among 550 patients in whom imager read cytology was cervical intraepithelial neoplasia grade 1 or higher and conventional cytology was less severe than grade 1, 133 of 380 biopsy samples taken were high grade histology. Among 294 patients in whom imager read cytology was less severe than cervical intraepithelial neoplasia grade 1 and conventional cytology was grade 1 or higher, 62 of 210 biopsy samples taken were high grade histology. Imager read cytology therefore detected 71 more cases of high grade histology than did conventional cytology, resulting from 170 more biopsies. Similar results were found when one pathologist reread the slides, masked to cytology results. Conclusion The ThinPrep Imager detects 1.29 more cases of histological high grade squamous disease per 1000 women screened than conventional cytology, with cervical intraepithelial neoplasia grade 1 as the threshold for referral to colposcopy. More imager read slides than conventional slides were satisfactory for examination and more contained low grade cytological abnormalities.

Renal biopsy morphology in renal transplantation. A comparative study of the light-microscopic appearances of biopsies from patients treated with cyclosporin A or azathioprine prednisone and antilymphocyte globulin.

Nephrotoxicity is a major side effect of cyclosporin A (CSA) when used in renal transplantation, and the distinction between nephrotoxicity and rejection is important in patient management. One hundred twenty-five renal biopsies were examined from 56 patients entered into a controlled clinical trial aimed at comparing the efficacy of CSA therapy alone to a combination of prednisone, azathioprine, and antilymphocyte globulin (AZA). In order to define the histopathology of rejection and nephrotoxicity, all the biopsies were evaluated in a semiquantitative manner by an observer unaware of the clinical state of the patient.Comparison of the morphological appearances of 32 biopsies from patients on CSA, and 22 biopsies from AZA-treated patients performed during clinically apparent rejection episodes showed that the histological patterns of rejection were the same in both treatment groups.Comparison of the morphological features of 34 biopsies from patients receiving CSA and 13 from patients receiving AZA, performed during prolonged periods of post-transplant renal failure, who eventually recovered on continuation of original therapy, showed that there were no morphological features specific to the CSA-treated group.Five patients on CSA had oliguria which was prolonged by CSA nephrotoxicity. Thirteen biopsies from all five patients showed a diffuse interstitial fibrosis that was peculiar to this group of patients.

Human papillomavirus messenger RNA expression in adenocarcinoma in situ of the uterine cervix

Over recent years, the association between human papillomavirus (HPV) and squamous cell carcinoma of the cervix and its precursors has been well established, largely as a result of advances in the techniques of molecular biology. A similar association between HPV and invasive adenocarcinoma of the cervix has also been recently demonstrated; however, little work has been published on the relationship between the precursor lesion, adenocarcinoma in situ (ACIS), and HPV. We have therefore undertaken an in situ hybridization study of 22 cases of known cervical ACIS using probes for HPV messenger RNA expression. Seventeen of these had residual ACIS in the blocks studied, 15 of which (88.6%) expressed HPV messenger RNA. Five cases were positive for HPV 16 and 10 cases for HPV 18. Early invasive adenocarcinoma was present with ACIS in three cases and one case had early invasion plus cervical intraepithelial neoplasia (CIN III). These invasive lesions showed a similar type and degree of HPV expression as the in situ component. One section had only residual CIN III, which was positive for HPV type 18. Four cases had only minor glandular atypias (less than ACIS) in the studied sections, and all four of these were negative for HPV expression. None of the normal endocervical epithelia in any of the sections were positive by this technique. In summary, the finding of HPV messenger RNA expression in nearly 90% of cervical ACIS supports a possible role for these viruses in the pathogenesis of glandular neoplasms of the uterine cervix.

Identification of the cellular subpopulations infiltrating rejecting cadaver renal allografts: Preponderance of the T4 subset of T cells

In the rejection response against renal allografts, the relative importance of helper/inducer T cells mediating a delayed-type hypersensitivity response and of T cells with direct cytotoxicity has not been defined. These subpopulations were identified with commercially available monoclonal antibodies and an indirect immunoperoxidase technique in 31 renal biopsies from patients undergoing acute rejection episodes and in 9 rejected nephrectomy specimens. T lymphocytes were the predominant cell population in all biopsies and in 8 of 9 nephrectomies. The T4 helper/inducer subset was equal to, or greater than, the T8 cytotoxic/suppressor subset in 28 of the 31 biopsies and in the 8 nephrectomy specimens that had histological evidence of cellular rejection. T4 lymphocytes were found predominantly in large areas of cellular infiltrate. T8 lymphocytes had a more diffuse interstitial distribution and were a minority of the cells in the large areas of cellular infiltration. These results show that helper/inducer T lymphocytes are often more frequent than cytotoxic/suppressor cells in acute renal allograft rejection in humans and they suggest that helper/inducer T cells may play an important role in the mediation of graft destruction.

The Study of the Prevention of Anal Cancer (SPANC): design and methods of a three-year prospective cohort study

BackgroundThe incidence of human papillomavirus (HPV)-associated anal cancer is increasing in men who have sex with men (MSM). Screening for the presumed cancer precursor, high-grade anal squamous intraepithelial lesions (HSIL) in a manner analogous to cervical cancer screening has been proposed. Uncertainty remains regarding anal HPV natural history and the role of anal cytology and high-resolution anoscopy (HRA) as screening tests. Well-designed cohort studies are required to address these issues.Methods/designThe SPANC study is a prospective study of the epidemiology of low-risk and high-risk anal HPV infection and related cytological and histological abnormalities in HIV-negative and HIV-positive homosexual men aged 35 years and over. The study aims to recruit 600 men from community-based settings in Sydney, Australia. There are six study visits over three years. At the first five visits men undergo a digital ano-rectal examination (DARE), an anal “Papanicolaou” (Pap) test for HPV detection, genotyping and anal cytology, followed by HRA and directed biopsy of any visible abnormalities. The men also complete a behavioural questionnaire before each visit. Questions include a detailed history of sexual behaviour, of anal symptoms, possible anal cancer risk factors and validated quality of life and psychosocial questions. Questionnaires are also completed 2 weeks and 3 months following the provision of test results and include questions on participant experience during the procedure and post-procedure symptoms, including pain and bleeding in addition to quality of life/ psychosocial outcomes.DiscussionRecruitment for the study began in September 2010 and will conclude in mid-2015, with follow up continuing to 2018. Thus far, over 350 men have been recruited from a variety of community-based settings and are broadly representative of the target screening population. The SPANC study is one of only a small number of cohort studies globally to perform HPV, cytology and HRA screening on all participants over multiple time points. The study results will contribute to understanding of the natural history of anal HPV and inform the possible development of guidelines for implementing anal cancer screening programs in this population.

The Reliability of a Cytological Prediction of Cervical Adenocarcinoma In Situ

EDITORIAL COMMENT: The entity of cervical adenocarcinoma in situ will be new to many readers. This careful large study established that cytological prediction of adenocarcinoma in situ of the cervix is a very meaningful finding, with a false positive rate of only 2% i.e. 1 of 47 patients having adequate investigation; the other 46 patients having in situ (28) or invasive (18) carcinomas. The authors have justified their conclusion that a cytological report of adenocarcinoma in situ of the cervix merits further investigation by cone biopsy. The appropriate management of very early or minimal microinvasive adenocarcinoma discovered at conization performed following a cytological prediction of adenocarcinoma in situ remains controversial, until such time as long term follow‐up of a series of such patients is reported.

A randomized crossover trial of PAPNET for primary cervical screening

OBJECTIVE To develop and demonstrate efficient methods to estimate the relative true positive and false positive rates of two cervical screening tests (conventional cytology and PAPNET). METHODS We designed the study to meet stringent methodologic criteria for comparison of two tests while simultaneously minimizing the numbers requiring reference standard verification. We used a cytology reference standard and also assessed histology when available. For the primary analysis, slides with discordant results around the test threshold (CIN 1) were reviewed by a panel of two cytopathologists, blind to previous results, to establish the reference standard result (reference standard threshold for abnormality CIN2). Where histology was available, a secondary analysis was conducted with the reference standard based on the highest grade lesion (either cytology or histology). RESULTS Among 21,747 Pap smears, 372 were discordant around the test threshold, requiring verification. In the primary analysis PAPNET detected four more true positives than conventional reading; difference in sensitivity 1.29% (95%CI -5.79 to 8.36%, P=.40). There were two extra false positives using PAPNET; difference in the false positive rate 0.0097% (95%CI -0.122 to 0.142%, P=.47). The results of the combined cytology and histology analysis were similar; difference in true positive rate 0.29% (95%CI -6.76 to 7.34%, P=.50) and difference in false positive rate 0.024% (95%CI -0.098 to 0.15%, P=.39). CONCLUSION This is an efficient and valid study design where the objective is to examine the comparative accuracy of two tests. The design provides an efficient means of estimating the difference between true positive and false positive detection by the two tests, which often is sufficient information for policy decisions.

The performance of anal cytology as a screening test for anal HSILs in homosexual men

Studies regarding the performance of anal cytology in which both the screening test (cytology) and the diagnostic test (high‐resolution anoscopy [HRA]) are performed in all members of a screening population are rare. The authors evaluated the performance of liquid‐based anal cytology in a cohort of homosexual men in Sydney, New South Wales, Australia.

Human Papillomavirus 16–Specific T-Cell Responses and Spontaneous Regression of Anal High-Grade Squamous Intraepithelial Lesions

BACKGROUND Most anal cancers are attributable to persistent human papillomavirus type 16 (HPV-16) infection. The anal cancer precursor, high-grade squamous intraepithelial lesion (HSIL), frequently regresses spontaneously. We hypothesized that T-cell responses are associated with HSIL regression. METHODS In men who have sex with men undergoing anal cytology and high-resolution anoscopy, we measured responses to HPV-16 oncogenic proteins E6 and E7, using the CD25/CD134 assay for CD4(+) antigen-specific T cells and intracellular cytokine staining for CD4(+) and CD8(+) antigen-specific T cells. RESULTS Of 134 participants (mean [SD] age, 51 [9.3] years; 31 [23.1%] infected with human immunodeficiency virus), 51 (38.1%) had HSIL. E6- and E7-specific CD4(+) T-cell responses were detected in 80 (59.7%) and 40 (29.9%) of the participants, respectively, and E6- and E7-specific CD8(+) T-cell responses were each detected in 25 (18.7%). HSIL was significantly associated with E7-specific CD8(+) T-cell responses (odds ratio, 4.09 [95% confidence interval, 1.55-10.77], P = .004), but not with any CD4(+) T-cell response (P ≥ .09). Twenty-six participants had HSIL a mean of 1 year before measurement of T-cell responses, and 6 (23%) of them were regressors. Five regressors (83%) had E6-specific CD4(+) T-cell responses vs 7 of 20 (35%) nonregressors (Pexact = .065). CONCLUSIONS Systemic HPV-16 E6- and E7-specific T-cell responses were common in men who have sex with men. E6-specific CD4(+) T-cell responses may be associated with recent HSIL regression. CLINICAL TRIALS REGISTRATION NCT02007421.

High reproducibility of histological diagnosis of human papillomavirus-related intraepithelial lesions of the anal canal

Summary In a natural history study of anal human papillomavirus (HPV) infection and HPV-related lesions, we examined the reproducibility of histological high-grade squamous intraepithelial lesion (HSIL). Three expert anogenital pathologists share the reporting of histological specimens from the Study of the Prevention of Anal Cancer (SPANC), utilising Lower Anogenital Squamous Terminology (LAST) criteria. In total, 194 previously reported biopsies were randomly chosen within diagnostic strata [50 HSIL–anal intraepithelial neoplasia (AIN) 3; 45 HSIL–AIN 2; 49 ‘flat’ low-grade squamous intraepithelial lesion (LSIL); 50 ‘exophytic’ LSIL; and 50 negative for squamous intraepithelial lesion] and reviewed by each of these three pathologists. Consensus was defined as agreement between at least two review diagnoses, using a binary classification of HSIL and non-HSIL, or if consensus was not obtained in this way, it was achieved through a multiheader microscope session by the three pathologists. We found very high agreement between original and consensus diagnoses (Kappa = 0.886) and between each pathologists review and consensus (Kappas = 0.926, 0.917 and 0.905). Intra-observer agreement for the three pathologists was 0.705, 1.000 and 0.854. This high level of diagnostic reproducibility indicates that the findings of SPANC should be robust and provide reliable information about HPV-related anal canal disease.