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M L Hutchinson

Publications and source records attributed to M L Hutchinson.

At least 19 recordsLinked to original sources
PubMed2001

Human leukocyte antigen class I and II alleles and risk of cervical neoplasia: results from a population-based study in Costa Rica.

To examine human leukocyte antigen (HLA) involvement in the development of all grades of cervical neoplasia, a nested case-control study of 10,077 women in Guanacaste, Costa Rica, was conducted. Participants had invasive cervical cancer, high-grade squamous intraepithelial lesions (HSILs; n=166), or low-grade squamous intraepithelial lesions (LSILs); were positive for human papillomavirus (HPV) with no evidence of cervical neoplasia (n=320); or were HPV negative with no evidence of cervical neoplasia but with a history of high-risk sexual behavior (n=173). Compared with women who were HPV negative, women with HLA-DRB1*1301 were associated with decreased risk for cancer/HSILs (odds ratio [OR], 0.4; 95% confidence interval [CI], 0.2-0.7) and for LSILs/HPV (OR, 0.6; 95% CI, 0.3-0.9). Women with both HLA-B*07 and HLA-DQB1*0302 had an 8.2-fold increased risk for cancer/HSILs (95% CI, 1.8-37.2) and a 5.3-fold increased risk for LSILs/HPV (95% CI, 1.2-23.7). These results support the hypothesis that multiple risk alleles are needed in order to increase risk for cervical neoplasia, but a single protective allele may be sufficient for protection.

Alleles↗
PubMed2001

Atypical squamous metaplastic cells: reproducibility, outcome, and diagnostic features on ThinPrep Pap test.

BACKGROUND: Atypical squamous metaplastic (ASM) cells are associated with high-grade squamous intraepithelial lesions (HGSIL) in many cases. The reproducibility of the diagnosis and biopsy follow-up results of cases designated as ASM were studied at Women and Infants' Hospital of Rhode Island. METHODS: Of 180 patients with ASM who the authors examined from January 1, 1998 to September 30, 1998, 147 (81.7%) had subsequent biopsies. Results of the biopsies were tallied. Twenty cases were rescreened in a blinded fashion to determine intra- and interobserver agreement and to identify diagnostic features. RESULTS: Sixty-five (44.2%) cases of ASM had HGSIL on biopsy, 26 (17.7%) had low-grade squamous intraepithelial lesion, and 56 cases (38.1%) were benign. Overall individual consistency is 8 of 16 (50%), and overall agreement is 13 of 64 (20%). CONCLUSIONS: Sixty-two percent of cases designated as ASM cytologically were associated with SIL, primarily HGSIL, at biopsies. The findings underscore the importance of this subcategory of atypical squamous cells. However, poor reproducibility suggests the need for refined criteria and/or continuing education, and obtaining second opinion. Cancer (Cancer Cytopathol)

Adult↗
PubMed2001

An association of cervical inflammation with high-grade cervical neoplasia in women infected with oncogenic human papillomavirus (HPV).

Previous reports of genital conditions, such as nonspecific genital infection/sore or vaginal discharge associated with cervical cancer (L. A. Brinton et al., J. Natl. Cancer Inst. (Bethesda), 79: 23-30, 1987; C. J. Jones et al., Cancer Res., 50: 3657-3662, 1990), suggest a possible link between either genital tract inflammation or changes in bacteria flora consistent with bacterial vaginosis (BV) and cervical cancer. To test whether changes in vaginal bacterial flora or the degree of cervical inflammation are associated with women having a human papillomavirus (HPV) infection or with women infected with oncogenic HPV having high-grade cervical lesions (high-grade squamous intraepithelial lesions or cancer), we conducted a case-control study of women <50 years old enrolled in the Costa Rican natural history study of HPV and cervical neoplasia. To test whether BV and inflammation were associated with HPV DNA positivity, Analysis 1 was restricted to women with no or mild (low-grade or equivocal) cytological abnormalities, and the degree of inflammation and Nugent score (a measure of BV) were compared between women infected (n = 220) and not infected (n = 130) with HPV. To test whether BV and inflammation were associated with high-grade lesions, Analysis 2 was restricted to women infected with oncogenic HPV, and the degree of inflammation and Nugent score were compared between women with (n = 95) and without (n = 158) high-grade cervical lesions. In Analysis 1, BV and cervical inflammation were not associated with HPV infection. In Analysis 2, BV was not associated with high-grade lesions. However, we found a marginally significant positive trend of increasing cervical inflammation associated with high-grade lesions in oncogenic HPV-infected women, (P(trend) = 0.05). Overt cervicitis was associated with a 1.9-fold increase in risk of high-grade lesions (95% confidence interval, 0.90-4.1). The results of this study suggest that cervical inflammation may be associated with high-grade lesions and may be a cofactor for high-grade cervical lesions in women infected with oncogenic HPV.

Adult↗
PubMed2000

Clinical and cost implications of new technologies for cervical cancer screening: the impact of test sensitivity.

OBJECTIVE: To compare the available techniques for cervical cancer screening, including several new technologies, using actual program utilization patterns. STUDY DESIGN: Longitudinal cohort model. PATIENTS AND METHODS: The model followed a cohort of 100,000 women who underwent screening from age 20 through 65 years. The model was run with a weighted average of screening intervals to model the actual utilization of the cervical cancer screening program in the United States. RESULTS: The model demonstrated that new technologies with significantly increased test sensitivity have the potential to reduce the number of cancers by 45% to 60% depending on the screening frequency in fully compliant populations. At screening intervals of 2 years or more, these new technologies had cost-effectiveness ratios below $50,000 per life-year saved. Assuming existing utilization patterns, the model predicted there would be 13.2 cancers per year in the 100,000 women screened with the conventional Pap smear, and new technologies with increased test sensitivity could reduce the annual incidence to 9.5 cancers per 100,000 women screened. CONCLUSIONS: The model suggests that to achieve further dramatic reduction in cervical cancer mortality, significant improvements in test sensitivity, as reflected in the new screening technologies, may be the most realistic and cost-effective approach.

Adolescent↗
PubMed1999

Utility of liquid-based cytology for cervical carcinoma screening: results of a population-based study conducted in a region of Costa Rica with a high incidence of cervical carcinoma.

BACKGROUND: In a study using a split-sample design, liquid-based cytology (ThinPrep Processor, Cytyc Corporation, Boxborough, MA) was compared with the conventional Papanicolaou (Pap) smear in Guanacaste, Costa Rica. The study provides the first population-based comparison of the ThinPrep screening technology and includes "gold standard" measures of diagnostic accuracy. METHODS: The population-based study was performed among over 8000 women residing in a Costa Rican province with a high incidence of cervical carcinoma. Conventional smears were prepared and diagnosed in Costa Rica, while the residual material on the sampling device was collected into a liquid preservative and shipped to the U.S., where ThinPrep cytologic slides were prepared and diagnosed. Cytologic diagnoses based on the two techniques, categorized according to the Bethesda System, were compared with a "gold standard" final case diagnosis for each patient, also based on Bethesda terminology, that reflected an integrated interpretation of all available data, including cytology, histology, and cervicography. Results were also compared with the results of HPV DNA detection (Hybrid Capture, Digene Corporation, Silver Spring, MD). RESULTS: ASCUS was the threshold for colposcopy referral. There were significantly more women referred according to this threshold with the ThinPrep slide (12.7%) than with the conventional smear (6.7%, P<0.001). Compared with the final case diagnosis, referral by ThinPrep slides detected 92.9% of cases with high grade squamous intraepithelial lesions (HSIL) and 100% of carcinoma cases. Smears detected 77.8% of HSIL and 90.9% of carcinomas. Thus, ThinPrep cytology was significantly more sensitive in the detection of HSIL and cancer (McNemar test, P<0.001). Adjudication of cases in which the ThinPrep and smear diagnoses disagreed, using the final case diagnoses and the HPV DNA test results as reference standards, suggested that the ThinPrep method was detecting additional true SIL as opposed to false-positives. CONCLUSIONS: In a population-based study of high risk women, ThinPrep cytology demonstrated significantly increased sensitivity for detecting HSIL and carcinoma, with a concurrent significant increase in colposcopy referrals.

Cervix Uteri↗
PubMed1999

Cervicography screening for cervical cancer among 8460 women in a high-risk population.

OBJECTIVE: Cervicography was evaluated as a primary screening method for cervical cancer. STUDY DESIGN: Cervigrams of 8460 women were taken on enrollment into a population-based study of cervical neoplasia. Cervicography results were compared with a referent diagnosis determined by histologic analysis and 3 cytologic tests, and with the performance of conventional cytologic evaluation. RESULTS: Cervicography identified all 11 cancers, whereas cytologic testing missed 1. Cervicography yielded sensitivities for detecting high-grade squamous intraepithelial lesions or cancer of 49.3% overall (specificity, 95.0%), 54.6% in women younger than 50 years of age, and 26.9% in women 50 years of age and older. Cytologic testing yielded sensitivities for detecting high-grade squamous intraepithelial lesions or cancer of 77.2% overall (specificity, 94. 2%), 75.5% in women younger than 50 years of age, and 84.6% in women 50 years of age and older. CONCLUSIONS: Cytologic testing performed better than cervicography for the detection of high-grade squamous intraepithelial lesions. Cervicography performed marginally better than cytologic testing for the detection of invasive cervical cancer. Cervicography is not recommended for postmenopausal women.

Adolescent↗
PubMed1999

Soluble interleukin 2 receptor levels and cervical neoplasia: results from a population-based case-control study in Costa Rica.

Progression from infection with human papillomavirus (HPV) to cervical cancer in some women is thought to involve a permissive host environment, one in which immune response is mobilized in an inappropriate manner. In a previous study (A. Hildesheim et al., Cancer Epidemiol. Biomark. Prev., 6: 807-813, 1997), increasing levels of soluble interleukin 2 receptor (sIL-2R), a known proxy for general immune activation, was found to be positively associated with increasing levels of cervical neoplasia. We attempted to confirm this finding by conducting a nested case-control study of 478 women within a 10,000-woman population-based cohort in Costa Rica. We selected for the study all of the women diagnosed (at enrollment into the cohort) with: (a) low-grade squamous intraepithelial lesions (LSIL, n = 191); (b) high-grade squamous intraepithelial lesions (HSIL, n = 130); or (c) cancer (n = 37). Controls were 120 cytologically normal, HPV-negative women selected from a random sample of the entire cohort. A questionnaire was administered to participants to elicit information on cervical cancer risk factors. All of the women received a pelvic examination during which cervical cells were collected and used for HPV DNA testing by PCR. Blood samples were also collected. Plasma obtained from the blood samples was tested for sIL-2R levels by ELISA. Results indicated that sIL-2R levels increased with age. Among controls, we observed that 44.3% of women over the age of 50 had high levels of sIL-2R (defined as >735 units/ml) compared with 15.8% of women <30 years of age (P = 0.008). When women with cervical disease (LSIL+) were compared with controls, women in the upper quartile of the sIL-2R distribution had an age-adjusted odds ratio (OR) of 2.1 [95% confidence interval (CI), 1.1-4.1]. Comparing each advancing state of neoplasia with its precursor, we found that women with LSIL had higher sIL-2R levels than controls (OR for upper quartile of sIL-2R, 2.3; 95% CI, 1.1-5.2; comparing LSIL cases with controls); women diagnosed with HSIL were similar to the LSIL group (OR for upper quartile of sIL-2R, 1.1; 95% CI, 0.5-2.4; comparing HSIL cases with LSIL cases); and those with cancer had higher sIL-2R levels than subjects with an HSIL diagnosis (OR for upper quartile of sIL-2R = 1.8; 95% CI, 0.5-7.1; comparing cancer cases with HSIL cases). These data suggest that among our study subjects, sIL-2R levels most likely rise as a response to the events of infection and cancerous invasion, but that sIL-2R levels are unlikely to be predictive of disease progression among women with LSIL.

Adolescent↗
PubMed1998

Performance of a semiautomated Papanicolaou smear screening system: results of a population-based study conducted in Guanacaste, Costa Rica.

BACKGROUND: Automated cytology devices have utility in quality assurance applications, but the effectiveness of these devices in primary screening is unknown. METHODS: Enrollment smears obtained from 7323 women participating in a population-based study sponsored by the National Cancer Institute were screened manually in Costa Rica and then evaluated independently in the U.S. with the PAPNET system (Neuromedical Systems, Inc., Suffern, NY), a semiautomated, neural network-based device. Smears with abnormal PAPNET images were microscopically rescreened and then diagnosed by a U.S. cytopathologist. ThinPrep slides (Cytyc Corporation, Boxborough, MA), prepared from rinses of the cytologic sampler, and cervigrams (National Testing Laboratories, Fenton, MO) were also evaluated. Women with any abnormal cytologic diagnosis or a positive cervigram were referred for colposcopy with biopsy and definitive therapy if indicated. RESULTS: Based on the U.S. cytotechnologist's review of the PAPNET images, 1017 (13.9%) of 7323 smears were selected for manual screening, resulting in the selection of 492 (6.7%) possibly abnormal slides for referral to the U.S. pathologist. Ultimately, 312 smears (4.3% of the total) were diagnosed as containing squamous cells of undetermined significance or a more severe abnormality (> or =ASCUS), resulting, hypothetically, in the referral of 66.5% of women with a final diagnosis of a squamous intraepithelial lesion or a more severe abnormality (> or =SIL) and 86.0% of patients with > or =high grade SIL. Conventional microscopic screening performed in Costa Rica resulted in the hypothetical referral of 6.5% of patients with > or =ASCUS for colposcopy, including 69.5% of patients with > or =SIL and 79.8% of those with > or =high grade SIL. CONCLUSIONS: In this study, PAPNET-assisted cytologic screening accurately identified smears obtained from women with high grade SIL or carcinoma. Determination of the clinical cost-effectiveness of PAPNET-assisted screening in routine practice awaits future study.

Cohort Studies↗
PubMed1997

Cervical specimens collected in liquid buffer are suitable for both cytologic screening and ancillary human papillomavirus testing.

BACKGROUND: Several new techniques have been developed to improve the sensitivity of cervical carcinoma screening and reduce equivocal cytologic diagnoses referred to as atypical squamous cells of undetermined significance (ASCUS). This study evaluates the effectiveness of combining two newly introduced diagnostic techniques: preparation of thin-layer cytologic slides from ThinPrep liquid buffer and selected Hybrid Capture testing for human papillomavirus (HPV) DNA. Because HPV DNA detection has been strongly associated with the presence of a cervical carcinoma precursor ("squamous intraepithelial lesion," or SIL), HPV testing might be useful for identifying women with ASCUS who have an underlying SIL. METHODS: Two hundred specimens demonstrating diverse cervical abnormalities were selected from a prospective population-based study of 9174 women conducted in Costa Rica. The entire cohort had been screened with conventional cervical smears; ThinPrep slides made from liquid buffer, PAPNET, a computerized slide reading system; and Cervicography. Patients with any abnormal screening test were referred for colposcopy, punch biopsy, and loop excision of cases with high grade cytologic abnormalities not explained by punch biopsy. For this investigation, the results of ThinPrep cytology and HPV testing alone and in combination were compared with the final diagnoses, with an emphasis on the detection of carcinoma and high grade SIL. RESULTS: The 200 subjects studied included 7 women with a final diagnosis of carcinoma, 44 with high grade SIL, 34 with low grade SIL, 51 with a variety of equivocal diagnoses, and 64 with normal diagnoses. A ThinPrep cytologic diagnosis of SIL or carcinoma was made in 39 (76%) of the 51 women with final diagnoses of high grade SIL or carcinoma. Hybrid Capture testing detected carcinoma-associated types of HPV DNA in 100% of women with carcinoma, 75% with high grade SIL, 62% with low grade SIL, 20% with equivocal final diagnoses, and 12% of normal women. If colposcopy referral had been limited to women with a ThinPrep diagnosis of SIL or a diagnosis of ASCUS associated with the detection of carcinoma-associated HPV DNA from the same vial, 100% of women with carcinoma and 80% with high grade SIL would have been examined. To achieve this high sensitivity in the entire population of 9174 women would have required the referral of about 7% of the population. The combined screening strategy would have performed marginally better than optimized conventional screening with referral of any abnormal cytology (ASCUS and above). CONCLUSIONS: A cervical carcinoma screening technique which uses a single sample for cytopathology and HPV testing to triage equivocal diagnoses may be promising if it proves to be cost-effective.

Carcinoma↗
PubMed1996

Cell surplus on sampling devices after routine cervical cytologic smears. A study of residual cell populations.

OBJECTIVE: To demonstrate whether considerable valuable cellular material remains on the sampling device after a conventional cervical cytologic smear and to investigate whether evidence of cervical disease may be present on the sampling device but missed because it is not represented on the first slide. STUDY DESIGN: Routine cervical cytologic smear material was taken from 60 women who were attending the colposcopy or gynecologic oncology clinic at New England Medical Center. At the time of the colposcopic examination, a cervical scrape was made using a Cytobrush followed by a Cervex brush. After the smear was made from each device, the sampling devices were also used to make four additional slides. Both the Cytobrush and Cervex brush were applied to each slide. RESULTS: Cytologically, all five slides were satisfactory for screening in the 60 cases. In all diagnostic cases but one, disease was well represented across all five slides. CONCLUSION: Cellular material collected in a cervical scrape is sufficient to prepare at least five satisfactory smears. The one case where an abnormality was detected only on the third slide suggests the possibility of nonrandom subsampling and of discarding the majority of the cellular material from the patient.

Cervix Uteri↗
PubMed1995

Combined malignancy associated change and contextual analysis for computerized classification of cervical cell monolayers.

Previous efforts to automate cervical cell analysis have focused on algorithms that use measurements of high resolution images of individual cells for 'rare event' detection of abnormal cells, sometimes in combination with cluster analysis of low resolution images. A new methodology was developed in which intermediate cell markers (indicating malignancy associated change) and contextual analysis of slide architecture were performed on the same digital images at 0.33 mu pixel resolution. A total of one hundred and forty-six cases that were either negative or at least high grade squamous intraepithelial lesions (HGSIL) were prepared as monolayers, and about 20 fields per slide were analyzed. Features most important for intermediate cell marker analysis were those that measured the variation in nuclear texture measurements across the slide as well as densitometric features. The most discriminatory contextual features were those that measured the variation of the arrangement of cells within a cluster across the slide. Linear discriminants were calculated using the most important features from both types of analysis; they provided smear classification accuracies of 71-86%.

Carcinoma↗
PubMed1994

Computerized contextual analysis in diagnosis.

Cervical cytology specimens prepared as monolayers were analyzed with a combination of high-resolution single-cell image analysis and lower-resolution contextual image analysis. For the latter, quantitative features of cluster architecture, object distribution and background were used to mimic the pathologists global assessment of a specimen. Contextual analysis correctly classified 81% of the cases for diagnosis, about on a par with the companion single-cell cytometric analysis. Contextual and single cell analysis complemented each other, yielding greater accuracy when the two methods were combined. Additional applications of contextual analysis are discussed.

Discriminant Analysis↗
PubMed1994

Homogeneous sampling accounts for the increased diagnostic accuracy using the ThinPrep Processor.

Recent clinical trials indicated that the ThinPrep method of sample preparation has greater diagnostic sensitivity than the conventional direct Papanicolaou smear. The authors hypothesized that nonhomogeneous cell sampling during transfer from the sampling device to the microscope slide was a contributing factor to the reduced accuracy of the conventional direct Pap smears in these trials. To test this hypothesis, four direct smear methods were compared with the newly developed, fluid-based, filter-transfer method. Counts of epithelial cells on conventional smears showed that only a fraction of the available epithelial cells on the sampling devices (medians, 6.5% to 62.5%) was actually deposited on the slides. In all 27 cases studied with the ThinPrep method, equivalent diagnostic material was obtained on each of the replicate slides prepared per specimen. This identifies a new source of error, preparation error, in conventional smears.

Cell Biology↗
PubMed1992

Measurement of subvisual changes in cervical squamous metaplastic cells for detecting abnormality.

Quantitative measures of visually normal squamous metaplastic cells exfoliated from the uterine cervix were obtained to test the hypothesis that these cells, like intermediate squamous and endocervical columnar cells, show subvisual evidence of atypia in cases of bonafide squamous intraepithelial neoplasia. The cells identified as squamous metaplastic were obtained from 14 abnormal (dysplastic) and 9 diagnostically negative cases. Although the cell populations so grouped showed no statistically significant differences in overall cell size, nuclear area or nuclear/cytoplasmic ratios, there were significant differences in nuclear and cytoplasmic densitometric features and in nuclear texture features. A combination of three features (nuclear density, texture and cytoplasmic density) permitted 76% of the cells to be categorized correctly as originating in normal versus abnormal slides. It is concluded that selected quantitative features of exfoliated metaplastic cell populations may contribute to improved diagnostic accuracy in automated screening for cervical abnormalities.

Cell Nucleus↗
PubMed1991

Contextual analysis and intermediate cell markers enhance high-resolution cell image analysis for automated cervical smear diagnosis.

Until now, efforts to automate cervical smear diagnosis have focused on analyzing features of individual cells. In a complex specimen such as that obtained from a cervical scrape, diagnostically significant cells may not be adequately represented or may elude detection by the automated technology. An approach is needed that extracts additional quantitative information from cervical smears beyond what the cell-by-cell approach can provide. A new methodology, contextual analysis, was developed to extract global quantitative information about cells, cell clusters, and background debris. This pilot study was designed to compare the efficacy of contextual analysis with high-resolution, single cell analysis and the analysis of intermediate cell markers. Thirty-four samples prepared as monolayers and stained with the Feulgen-Thionin/Congo Red stain were measured. Contextual analysis alone was able to classify 91% of the smears correctly; single cell analysis classified 94% of the cells correctly; and the intermediate cell analysis correctly identified the smear diagnosis for 84% of the cells. When all three analysis methods were combined into a simple smear level classifier, the overall smear classification accuracy was improved over those obtained using the three methodologies alone.

Biomarkers↗
PubMed1991

The efficacy of an automated preparation device for cervical cytology.

A new automated method for collecting and preparing cells for cytologic screening (termed the ThinPrep process) was tested. Four hundred forty-nine specimens prepared by ThinPrep and conventional methods were evaluated. This study compared specimen adequacy and detection of disease with the two methods. For the ThinPrep method, exfoliated cells were collected in suspension, gently dispersed, collected on a polycarbonate filter, and transferred to a glass slide. The ThinPrep method reduced the number of smears that lacked endocervical columnar cells by 24%. Significant improvement with the ThinPrep, versus the conventional method, also was found for detection of low-grade cervical intraepithelial lesions. Thus, the ThinPrep method improved specimen quality and reliability of cytologic detection of cervical neoplasia.

Automation↗