Gastric ciliated metaplasia. A study of 3406 gastrectomy specimens from dwellers of the Atlantic and the Pacific basins.

BACKGROUND: Ciliated cells in gastrectomies from patients dwelling in the Pacific and Atlantic basins have been reported previously. AIM: To compare all the results in an attempt to explain the findings. METHODS: Sections from 3406 gastrectomies were reviewed: 1966 and 1440 from the Atlantic and Pacific basins, respectively. Ciliated cells and intestinal metaplasia (IM) were recorded; IM was classified into focal or extensive IM. The total number of sections/gastrectomy was noted. RESULTS: In the Atlantic basin, 5% of specimens had ciliated metaplasia (CM); it was more frequent in intestinal carcinoma (IC; 9%) than diffuse carcinoma (DC; 3%) or miscellaneous gastric diseases (MGD; 3%). In the Pacific basin, the frequency of specimens with CM was 29%: it was more frequent in IC (43%) than in DC (16%) or MGD (10%). The difference between the frequency of CM in specimens with IC or with DC/MGD in the Atlantic and the Pacific basins was significant (p < or = 0.05). The presence of CM was influenced by age and the extent of IM in both basins, but not by sex or the number of sections investigated. CONCLUSIONS: CM-apparently an independent microscopic marker-was significantly higher in the Pacific than in the Atlantic basin. Environmental carcinogens involved in the evolution of IM and IC seem to be implicated in gastric ciliogenesis. Carcinogens that differ in nature and/or in strength in both basins might activate the latent natural genes encoding ciliated processes in gastric cells in patients subsequently developing gastric carcinoma, more notably of intestinal type.

Inter-observer variation in cytological and histological diagnoses of cervical neoplasia and its epidemiologic implication.

Inter-observer variation in cytohistological diagnosis was assessed for 1506 cervical smears and 883 histological slides from four case-control studies on cervical neoplasia. The kappa statistic among a panel of three cytopathologists was highest for diagnosis of invasive cancer (0.70 for cytology and 0.74 for histology), followed by normal/inflammatory in cytology (0.68) and CIN III in histology (0.58). There was also nearly perfect agreement between the final panel diagnoses and the original diagnoses made by local cytopathologists, except for those of CIN III. Inter-observer variation in diagnosis for CIN III was inversely associated with age, number of children (in histology) and sexual activity (in cytology). However, the odds ratios for CIN III calculated by each cytopathologist's diagnosis were not different from each other for any etiologic factor. These results indicate that the diagnoses of invasive cancer and of normal/inflammatory changes are highly reproducible and that the inter-observer variation does not have much impact on the etiologic risk estimates.

Evaluation of the cervical cancer screening programme in Mexico: a population-based case-control study.

BACKGROUND: This study presents the evaluation of the Mexico City Cervical Cancer Screening Programme (CCSP). Uterine cervical cancer (CC) is still a major public health problem in Mexico. Various actions aimed at reducing mortality from CC have been unsuccessful with an estimated 62000 deaths reported between 1980 and 1995. METHODS: The authors performed a study of cases and controls chosen on a population basis that included a sample of 233 cases of cancer in situ, and 397 cases of invasive cervical cancer obtained from eight hospitals, and a sample of 1005 controls representative of the general population. The results are presented stratified by case type, classified according to whether the cancer is invasive or not. RESULTS: The results show low impact of the cervical cancer screening programme in Mexico. Women who had a history of use of the Papanicolaou smear (PAP), who did not seek testing due to gynaecological symptoms and who had received their PAP results, had a 2.63 times lower risk of developing invasive cervical cancer (OR = 0.38; 95% CI: 0.28-0.52). CONCLUSIONS: The principal findings of this study in relation to the low impact of the screening programme in Mexico, are the low level of existing coverage and late use of health services by women at risk.

Geographic variations in the histologic characteristics of the gastric mucosa.

Histologic sections of 205 gastrectomy specimens, which were obtained for benign and malignant diseases, were reviewed. All patients were Mexican nationals. The following histologic features were recorded: intestinal metaplasia, intramucosal cysts, ciliated gastric cells, and different types of pyloric cells ("ordinary"; with granular cytoplasm; with small cytoplasmic vacuoles; with large cytoplasmic vacuoles; or with homogeneous "glassy" cytoplasm). The percentage of specimens showing intestinal metaplasia was similar in those containing gastric ulcers (42.7%) or adenocarcinomas (50.0%). Intestinal metaplasia was decreased in men 59 years of age or older and in women 69 years of age or older. Diffuse-type adenocarcinoma accounted for 90% of the gastric tumors. Only 3 of the 205 specimens (1.9%) contained intramucosal cysts, and only 1 (0.4%) showed ciliated cells. Pyloric cells with granular cytoplasm were observed in 21.2% of the specimens, and pyloric cells with small cytoplasmic vacuoles were seen in 1.9%. Pyloric cells with large vacuoles or "glassy" cytoplasm were not found in any case. These results indicate differences in the proportions of several histopathologic findings in the gastric mucosa, between Mexicans and other ethnic groups that have been investigated in previous surveys. The authors' findings support the hypothesis that different environmental factors, acting in disparate geographic regions, may account for dissimilarities in the histologic appearance of "normal gastric mucosa."

Quality control study on negative gynecological cytology in Mexico.

An external evaluation of the quality of diagnosis of gynecological cytology specimens (Papanicolaou or "Pap" tests) in the Cytopathological Laboratory at the Mexico General Hospital was performed, with evaluation of 6,011 Pap tests randomly selected from 31,378 Pap studies previously reported as negative during 1988-1989. These tests were part of the early detection program for cervical cancer run by the Ministry of Health of Mexico City. A quality index for specimens was constructed based on the presence of endocervical cells, mucus, and squamous metaplastic cells. The index of false negatives for the diagnosis of cervical neoplasm in this sample which correspond to diagnostic error by the examiner was 0.18% (11). The constructed quality index revealed that 64.1% of specimens were low quality. The correlation between diagnostic error and low quality was .87. Results indicate that laboratories participating in early detection programs for cervical cancer in developing countries need to implement (1) external evaluation programs for Pap diagnosis; (2) permanent training programs in registration; and (3) monitoring procedures for collection, fixation, and transportation of cytologic materials.

[Diagnostic concordance in gynecologic cytology]. / Concordancia diagnóstica en citología ginecológica.

OBJECTIVE: To evaluate the diagnostic agreement in Papanicolaou of pathologists and cytotechnologists using kappa values for concordancy. METHODS: The diagnostic variation was estimated in 20 gynecological cytology (Pap) specimens by 30 pathologists and 7 cytotechnologists attending the XXXVII Congress of the Mexican Association of Pathologists in 1994. RESULTS: The best concordancy versus an expert was in tumoral diathesis (pathologists' kappa = 0.36; cytotechnologists' kappa = 0.35) and kollocytos (pathologists' kappa = 0.55; cytotechnologists' kappa = 0.36). The least concordancy was observed in anisonucleosis (pathologists' kappa = 0.11; cytotechnologists' kappa = 0.02), nuclear hyperchromasia (pathologists' and cytotechnologists' kappa = 0.11) and dyskeratosis (pathologists' kappa = 0.11; cytotechnologists' kappa = 0.16). The kappa values for cervical neoplasia showed poor agreement, and in invasive cervical cancer it was 0.30. CONCLUSIONS: There was a low concordancy of Pap diagnosis in the study. It is convenient to try to improve the concordancy of cytologic diagnosis in Mexico. One strategy could be the use of a uniform diagnostic criteria and the adoption of a single nomenclature.

Diagnostic reproducibility of Pap testing in two regions of Mexico: the need for quality control mechanisms.

To assess the reproducibility of diagnostic results obtained by examining Pap smears for cervical neoplasia, a study was conducted using a single group of 20 Pap smears, 3 negative and 17 from patients with varying degrees of neoplasia. These smears were examined by 14 volunteer readers (13 cytotechnologists and 1 cytopathologist) from the Mexican states of Oaxaca and Veracruz, and also by a highly experienced cytopathologist certified by the Mexican Board of Pathological Anatomy whose work provided a reference standard. Individual variability, as assessed by the Kappa coefficient of concordance, showed considerable difference in the diagnostic results obtained by different readers-the degree of agreement depending on the type of cervical lesion involved and the number of specimens from patients with that type of lesion. There was little diagnostic agreement when the specimens were assessed for particular classes of cervical neoplasia-mild, moderate, or severe neoplasia, carcinoma in situ, or invasive cervical cancer. (The greatest concordance was found in diagnosing specimens from subjects with invasive cervical cancer.) However, when the diagnosis was assessed continuously, using Kappa weighted in accordance with the five possible diagnoses of cervical neoplasia, the apparent reproducibility of the diagnoses improved greatly, Kappa coefficients for the 14 readers ranging from 0.31 to 0.72. In general, these data support the view that there is a need in Mexico and other parts of the Americas to establish quality control mechanisms monitoring cytologic diagnosis of cervical neoplasia, to standardize diagnostic nomenclature using a system such as the Bethesda System, to institute periodic certification, and to provide continuing training. As this suggests, it is necessary not only to evaluate but also to bring about organizational changes in order to expeditiously prevent or correct the problems that currently constrain achievement of efficient and effective cytologic diagnosis.

Barriers to early detection of cervical-uterine cancer in Mexico.

In Mexico, a woman dies of cervical-uterine cancer every 2 hours, indicating a low impact by the national program for early detection of this cancer, principally because of problems related to quality and coverage. Through a qualitative study, we identified the principal barriers to use of the detection program from the point of view of actual and potential program users. Four focus groups were organized in standard conditions in Mexico City (urban, developed) and in the southern state of Oaxaca (rural, economically disadvantaged area). Participants were either women with at least one previous Papanicolaou (Pap) test or women who had never had the test. Barriers to Pap test use included (1) lack of knowledge about cervical-uterine cancer etiology, (2) not knowing that the Pap test exists, (3) the conception that cancer is an inevitably fatal disease, (4) problems in doctor/medical institution-patient relationships, (5) giving priority to unmet needs related to extreme poverty, (6) opposition by the male sexual partner, (7) rejection of the pelvic examination, (8) long waits for sample collection and receiving results, and (9) perceived high costs for care. To increase coverage of the early detection program for cervical-uterine cancer in Mexico, the needs, perceptions, and beliefs of women and their partners must be taken into account when developing policy and planning, given the role these factors play in the decision-making process that leads to their participation or nonparticipation in this program.

Mexico City physicians' awareness about cervical cancer prevention: implications for cancer screening.

BACKGROUND: In spite of an early cancer detection program (CCSP), Mexico has a mortality rate for cervical cancer of 16.5 per 100,000 women. METHOD: A cross-sectional study of 330 physicians at the Mexico City General Hospital evaluated their knowledge of the CCSP, etiology, diagnostic alternatives, and treatment guidelines. Variance analysis was the statistical procedure used. Replies to a questionnaire about cervical cancer prevention awareness were scored on a scale from 1 to 9. RESULTS: According to the awareness scale, the global average classification was 4.4, with 50% of the physicians scoring 4 or less. There was no difference in the CCSP knowledge scores of gynecologists (mean 4.92, 95% CI 4.2-5.3), oncologists (mean 4.85, 95% CI 4.3-5.5), pathologists (mean 5.23, 95% CI 4.9-5.6), and those in other specialties (mean 4.29, 95% CI 4.2-5.0), p > 0.05. Many respondents attributed CCSP's lack of effectiveness to public apathy (68.12%). CONCLUSIONS: The effectiveness of the CCSP can be improved by educating health professionals if this education is combined with elimination of obstacles to its use. More information is needed to justify revising how doctors are educated in terms of not only quality of the training but also the contents of pre- and postgraduate training programs.

Factors associated with Mexican women's familiarity with the purpose of the Pap test.

Use of health services is usually associated with a variety of factors, including the socioeconomic characteristics of the users, their familiarity with the usefulness of the services provided, and the acceptability and accessibility of those services. To study the factors associated with women's familiarity with the Pap test, a population-based study was carried out in Mexico City and two rural areas in the state of Oaxaca by means of household interviews. The sample consisted of 4208 women 15 to 49 years of age. Univariate, bivariate, and multivariate analyses were done using unconditional logistic regression; the independent variables were access to social security health services, age, education, housing quality, and place of residence (urban or rural); the dependent variable was the interview subject's familiarity with the purpose of the Pap test. The results were expressed as odds ratios with 95% confidence intervals. It was found that 41.5% of the women surveyed did not know the purpose of the Pap test, and that within this latter group, 97% had never had one. Factors found to be associated with not knowing the test's purpose were lack of access to the social security health services (OR = 1.9; 95% CI: 1.5-2.3); illiteracy (OR = 36.1; 95% CI: 17.9-72.7); and low socioeconomic level (OR = 2.9; 95% CI: 2.3-3.7). Also, rural dwellers had less familiarity with the Pap test than urban dwellers (OR = 0.5; 95% CI: 0.4-0.7). These results highlight the need to develop strategies for making the benefits of the Pap test known, bearing in mind the socioeconomic and cultural diversity of the populations involved.