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RESUMEN Introducción: los injertos óseos constituyen una de las técnicas más utilizadas en la cirugía reconstructiva implantológicas, son muy utilizadas para el reemplazo del hueso perdido por traumatismos, procesos patológicos congénitos o adquiridos y atrofia, son los injertos óseos autógenos o autólogos. Objetivo: caracterizar los pacientes con rebordes atróficos que necesitaron ser rehabilitados en implantología oral como alternativa de tratamiento en la consulta de Cirugía Máxilo Facial del Hospital Universitario "Faustino Pérez" y la Clínica "III Congreso del PCC", municipio Matanzas de septiembre del 2014 a julio de 2016. Material y Método: estudio prospectivo longitudinal. El universo fue de 20 pacientes mayores de 18 años de ambos sexos, que presentaron el diagnóstico de edentulismo parcial y atrofia alveolar. Se determinó por el interrogatorio, el examen clínico y los medios diagnósticos los síntomas y signos que caracterizaron esta entidad. Resultados: los traumatismos alveolares fue la causa que predominó en la pérdida dentaria, en el sexo masculino y en las edades de 18 a 37 años. La zona de mayor afectación fue la región anterior del maxilar superior y predominó la perdida de hueso en altura y en anchura y un gran número de injertos conservaron la cresta alveolar. Conclusiones: el uso de biomateriales en el tratamiento de pacientes con atrofia alveolar junto al injerto óseo fue satisfactorio en pacientes que necesitaron una base de sostén sobre la cual se colocaron los implantes dentales osteointegrados (AU).
SUMMARY Introduction: autogenous and autologous bone grafts are the elective material for replacing bones lost by trauma, congenital or acquired pathologic processes and atrophy. Objective: to characterize patients with atrophic rims needing rehabilitation in oral grafting as an alternative treatment in the Maxilla-Facial Surgery consultation of the University Hospital "Faustino Perez" and the Clinic "III Congreso del PCC", municipality of Matanzas, from September 2014 to July 2016. Materials and Methods: longitudinal prospective study. The universe was 20 patients aged 18 years and older, males and females, who presented the diagnosis of partial lack of teeth and alveolar atrophy. The symptoms and signs characterizing this entity were stated by questioning, physical examination and diagnostic means. Results: alveolar traumas were the predominant cause of dental lost in male patients aged 18-37 years. The most affected zone was the anterior region of the upper maxilla; bone lost in height and width predominated, and a great number of grafts conserved the alveolar crest. Conclusions: the use of biomaterials in the treatment of patients with alveolar atrophy together with bone graft was satisfactory in patients who needed a base support on which to put dental grafts (AU).
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Humanos , Niño , Adolescente , Proceso Alveolar/patología , Aumento de la Cresta Alveolar , Alveolectomía , Injerto de Hueso Alveolar , Rehabilitación , Atrofia/diagnóstico , Atrofia/etiología , Atrofia/epidemiología , Cirugía Bucal , Epidemiología Descriptiva , Estudios Transversales , Estudio ObservacionalRESUMEN
INTRODUCTION: To evaluate whether the presence of prostate atrophy (P.A.) in negative prostate biopsy is associated with prostate cancer (P.C.a) grade at surgical pathology among men who are ultimately diagnosed with P.C.a and undergo radical prostatectomy (R.P.). METHODS: A retrospective analysis was performed of 136 men from the placebo arm of the Reduction by Dutasteride of P.C.a Events (R.E.D.U.C.E.) trial who had a baseline prostate biopsy negative for P.C.a, and were later diagnosed with P.C.a on biopsy and underwent radical prostatectomy over the 4-year study period. The association of baseline P.A. (present/absent) with P.C.a grade (W.H.O./I.S.U.P. grade group 1 or ≥2) at surgical pathology was evaluated with logistic regression in uni- and multivariable analyses, controlling for baseline patient characteristics. RESULTS: P.A. was observed in 74 prostate biopsies (54%). P.A. was not associated with baseline characteristics (age, body mass index, prostate-specific antigen level, prostate volume, race, family history of P.C.a, and digital rectal exam), except for chronic inflammation (p = 0.001). The presence of P.A. in baseline prostate biopsies was associated with lower risk of W.H.O./I.S.U.P. grade group ≥2 P.C.a in R.P. specimens on both univariable (O.R. = 0.39, 95% C.I. = 0.19-0.78, p = 0.008) and multivariable (O.R. = 0.43, 95% C.I. = 0.20-0.92, p = 0.029) analyses. CONCLUSIONS: Among men with a baseline prostate biopsy negative for P.C.a who were later found to have P.C.a and underwent R.P., baseline P.A. is independently associated with lower risk of W.H.O./I.S.U.P. grade group ≥2 P.C.a on surgical pathology. P.A. may be used to identify subjects at lower risk for W.H.O./I.S.U.P. ≥ 2 P.C.a and select optimal candidates for active surveillance.
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Próstata/patología , Neoplasias de la Próstata/patología , Anciano , Atrofia/epidemiología , Biopsia , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Clasificación del Tumor , Oportunidad Relativa , Prostatectomía , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos , Factores de RiesgoRESUMEN
OBJECTIVE: There have been few studies in which the prevalence of cerebral atrophy in childhood-onset systemic lupus erythematosus (SLE) was evaluated using magnetic resonance imaging (MRI) volumetric measurements. This study was undertaken to determine the prevalence of cerebral and corpus callosum atrophy in childhood-onset SLE and to determine the possible relationships between atrophy and clinical, laboratory, and treatment features of the disease. METHODS: We included 76 patients with childhood-onset SLE (69 female and 7 male; median age 16 years) and 66 age- and sex-matched healthy controls. Neurologic manifestations were analyzed according to the American College of Rheumatology (ACR) criteria. These SLE patients were further assessed for clinical and laboratory manifestations of SLE, disease activity (using the SLE Disease Activity Index), damage (using the Systemic Lupus International Collaborating Clinics/ACR Damage Index), and current and cumulative drug exposures. Scans were performed with a Philips 3.0T MRI scanner using a standardized protocol. RESULTS: Childhood-onset SLE patients had significantly smaller cerebral and corpus callosum volumes than controls (median cerebral volume 1,067.9 cm(3) versus 1,172.7 cm(3) and median corpus callosum volume 11.6 cm(3) versus 13.7 cm(3) ; P < 0.001). The presence of structural abnormalities was observed in 42 patients (55.3%) with childhood-onset SLE. The presence of cerebral atrophy was associated with anticardiolipin antibodies (aCL) (P = 0.02), anti-double-stranded DNA (P = 0.02), and cumulative corticosteroid dose (P = 0.04). The presence of corpus callosum atrophy was associated with low complement level (P = 0.006) and acute confusional state (P = 0.01). Serum levels of S100B or high molecular weight neurofilament and the presence of anti-ribosomal P were not associated with atrophy. CONCLUSION: Structural brain abnormalities were observed in 55.3% of the patients and were associated with neuropsychiatric manifestations, aCL, and corticosteroid use. To determine permanent neurologic damage, longitudinal studies must be conducted in these patients.
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Encéfalo/diagnóstico por imagen , Encéfalo/patología , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/patología , Lupus Eritematoso Sistémico/diagnóstico por imagen , Lupus Eritematoso Sistémico/patología , Imagen por Resonancia Magnética , Adolescente , Anticuerpos Anticardiolipina , Atrofia/diagnóstico por imagen , Atrofia/epidemiología , Femenino , Humanos , Lupus Eritematoso Sistémico/terapia , Masculino , Tamaño de los Órganos , PrevalenciaRESUMEN
OBJECTIVE: The effect of hypoglycemia related to treatment of type 2 diabetes mellitus (T2DM) on brain structure remains unclear. We aimed to assess whether symptomatic severe hypoglycemia is associated with brain atrophy and/or white matter abnormalities. RESEARCH DESIGN AND METHODS: We included T2DM participants with brain MRI from the Action to Control Cardiovascular Risk in Diabetes-Memory in Diabetes (ACCORD-MIND) trial. Symptomatic severe hypoglycemia was defined as blood glucose <2.8 mmol/L or symptoms resolved with treatments that required the assistance of another person or medical assistance (hypoglycemia requiring assistance [HA]). Standardized brain MRI was performed at baseline and at 40 months. Total brain volume (TBV) and abnormal white matter (AWM) volume were calculated using an automated computer algorithm. Brain MRI scans of hypoglycemic participants were also reviewed for local disease. RESULTS: Of the 503 T2DM participants (mean age, 62 years) with successful baseline and 40-month brain MRI, 28 had at least one HA episode during the 40-month follow-up. Compared with participants without HA, those with HA had marginally significant less atrophy (less decrease in TBV) from baseline to 40 months (-9.55 [95% CI -15.21, -3.90] vs. -15.38 [95% CI -16.64, -14.12], P = 0.051), and no significant increase of AWM volume (2.06 [95% CI 1.71, 2.49] vs. 1.84 [95% CI 1.76, 1.91], P = 0.247). In addition, no unexpected local signal changes or volume loss were seen on hypoglycemic participants' brain MRI scans. CONCLUSIONS: Our study suggests that hypoglycemia related to T2DM treatment may not accentuate brain pathology, specifically brain atrophy or white matter abnormalities.
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Encéfalo/patología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemia/inducido químicamente , Hipoglucemia/patología , Hipoglucemiantes/efectos adversos , Imagen por Resonancia Magnética , Adulto , Anciano , Atrofia/inducido químicamente , Atrofia/epidemiología , Atrofia/patología , Glucemia/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/patología , Femenino , Humanos , Hipoglucemia/epidemiología , Masculino , Memoria/efectos de los fármacos , Persona de Mediana Edad , Factores de RiesgoRESUMEN
Chronic inflammation and infection are major risk factors for gastric carcinogenesis in adults. As chronic gastritis is common in Mexican children, diagnosis of Helicobacter pylori and other causes of gastritis are critical for the identification of children who would benefit from closer surveillance. Antral biopsies from 82 Mexican children (mean age, 8.3 ± 4.8 years) with chronic gastritis (36 H pylori+, 46 H pylori-) were examined for gastritis activity, atrophy, intestinal metaplasia (IM), and immunohistochemical expression of gastric carcinogenesis biomarkers caudal type homeobox 2 (CDX2), ephrin type-B receptor 4 (EphB4), matrix metalloproteinase 3 (MMP3), macrophage migration inhibitory factor (MIF), p53, ß-catenin, and E-cadherin. Atrophy was diagnosed in 7 (9%) of 82, and IM, in 5 (6%) of 82 by routine histology, whereas 6 additional children (7%) (3 H pylori+) exhibited aberrant CDX2 expression without IM. Significant positive correlations were seen between EphB4, MMP3, and MIF (P<.0001). Atrophy and follicular pathology were more frequent in H pylori+ biopsies (P<.0001), whereas IM and CDX2 expression showed no significant correlation with H pylori status. Antral biopsies demonstrating atrophy, IM, and/or aberrant CDX2 expression were seen in 21.95% (18/82) of the children, potentially identifying those who would benefit from closer surveillance and preventive dietary strategies. Biomarkers CDX2, EphB4, MMP3, and MIF may be useful in the workup of pediatric gastritis.
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Gastritis/patología , Infecciones por Helicobacter/patología , Helicobacter pylori , Enfermedades Intestinales/patología , Lesiones Precancerosas/patología , Antro Pilórico/patología , Adolescente , Anciano , Anciano de 80 o más Años , Atrofia/epidemiología , Atrofia/metabolismo , Atrofia/patología , Biomarcadores/metabolismo , Niño , Preescolar , Comorbilidad , Femenino , Gastritis/epidemiología , Gastritis/metabolismo , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/metabolismo , Humanos , Lactante , Enfermedades Intestinales/epidemiología , Enfermedades Intestinales/metabolismo , Masculino , México , Persona de Mediana Edad , Vigilancia de la Población , Lesiones Precancerosas/epidemiología , Lesiones Precancerosas/metabolismo , Antro Pilórico/metabolismoRESUMEN
INTRODUCTION: Gastric adenocarcinoma of intestinal type is preceded by inflammation, which produces mucosal atrophy and intestinal metaplasia, progressing eventually to dysplasia and invasive cancer. Recently an international group, the Operative Link on Gastritis Assessment (OLGA) proponed a staging system for gastric biopsies. OBJECTIVE: To recognize the distribution of advanced stages of gastric mucosal atrophy in Mexican patients with dyspepsia according to the OLGA system. METHODS: We apply the OLGA system for cancer risk (Stages 0 to IV) to 322 gastric biopsies from consecutive patients with dyspepsia. Using the Sydney protocol, we recorded the presence of atrophy, dysplasia and the relationship with ulcer disease. We report the stage of atrophy for each region and the Helicobacter pylori infection status. RESULTS: We documented 72 (22.4%) cases with atrophy, 50 of them (69.4%) were metaplastic-type. Overall, nine biopsies (2.78%) were stage III (all of them with metaplastic-type atrophy) and there was not stage IV cases. We did not find high-grade dysplasia or intramucosal carcinoma. In 8 of subjects with stage III, we observed low-grade dysplasia. We documented gastric ulcer in 5 patients with stage II, 60% of them with associated low-grade dysplasia. Five patients with duodenal ulcer were found in stages 0 and I. CONCLUSIONS: We found low prevalence of advanced stages of mucosal gastric atrophy among patients with dyspepsia. However we recognized 9 patients with stage III according to OLGA system worthy of follow-up because the high risk for developing gastric cancer.
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Gastritis Atrófica/epidemiología , Gastritis Atrófica/patología , Adolescente , Adulto , Atrofia/epidemiología , Biopsia , Progresión de la Enfermedad , Femenino , Mucosa Gástrica/patología , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Prevalencia , Adulto JovenRESUMEN
BACKGROUND: The intestinal gastric cancer is preceded by a sequence of pathological changes whose link is mucosal atrophy. The modified Sydney system for atrophy is a parameter not reproducible among pathologists. AIM: To know the interobserver variability using the OLGA system (Operative Link on Gastritis Assessment). METHODS: We selected 116 histologic slides. Sixty cases of both types of atrophy and 56 without atrophy were included. Three general pathologists, interested in gastrointestinal biopsies independently review the slides and established a diagnosis. For statistical analyses we employed singles frequencies in order to describe the individual diagnosis and the kappa test for evaluate the concordance between 2 and 4 observers with 2 and 3 categories. RESULTS: The global concordance has a kappa index of 0.48 (IC 95% 0.4-0.57). When we compared two pathologists the kappa index varies from 0.82(IC 95% 0.73-0.91) to 0.36 (IC 95% 0.22-0.5). The consensus among three pathologists was achieved in 25 out 30 slides in the metaplastic variety and 11 out 30 for the non-metaplastic type. The concordance for the atrophy scale has a kappa index between 0.2 and 0.5. CONCLUSION: The problematic atrophic evaluation with the Sydney system justify every effort to improve the interobserver evaluation. The OLGA system seems reproducible, although laborious,it requires a careful application, but with daily practice it could be applied easier. The clinician acceptation becomes crucial.
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Gastritis Atrófica/patología , Estómago/patología , Atrofia/epidemiología , Femenino , Gastritis Atrófica/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del ObservadorRESUMEN
BACKGROUND: histopathologic identification of atrophy and metaplasia is decisive to stop the way of gastritis?carcinoma in patients with chronic gastritis. OBJECTIVE: to compare diagnostic concordance between Sidney system and the operative Link on Gastritis Assessment (OLGA) system. METHODS: 120 consecutive biopsies were analyzed by general pathologists according to the Sidney system. All of them were evaluated by a second pathologist who used OLGA System. We employed kappa index to evaluate diagnostic concordance between the classifications. RESULTS: the clinical picture includes dyspepsia (94 %), abdominal pain (50 %), gastroesophageal reflux (30 %), bleed of the upper digestive system (24 %), and presence of Helicobacter pylori (47.5 %). Four were diagnosed as atrophy by Sidney system and 26 cases with atrophy by OLGA system. The concordance between two classifications systems was too low (p = 0.05). CONCLUSIONS: the atrophy diagnosis, between systems, had low concordance. The description of metaplastic atrophy in the OLGA system represents the only one difference. The non-metaplastic atrophy is the same for both classifications. Therefore, the general pathologist should include this evaluation more consistently using OLGA system.
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Gastroenterología/métodos , Estómago/patología , Adulto , Anciano , Anciano de 80 o más Años , Atrofia/epidemiología , Atrofia/microbiología , Atrofia/patología , Australia/epidemiología , Áreas de Influencia de Salud , Femenino , Gastritis/epidemiología , Gastritis/microbiología , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Estómago/microbiología , Adulto JovenRESUMEN
AIM: To validate a non-invasive method to detect gastric mucosal atrophy in a Chilean population with high prevalence of gastric cancer and a poor survival rate. METHODS: We first determined the optimal cut-off level of serum pepsinogen (PG)-1, PG-1/PG-2 ratio and 17-gastrin in 31 voluntary symptomatic patients (mean age: 66.1 years), of them 61% had histologically confirmed gastric atrophy. Then, in a population-based sample of 536 healthy individuals (209 residents in counties with higher relative risk and 327 residents in counties with lower relative risk for gastric cancer), we measured serum anti-H pylori antibodies, PG and 17-gastrin and estimated their risk of gastric cancer. RESULTS: We found that serum PG-1 < 61.5 microg/L, PG-1/PG-2 ratio < 2.2 and 17-gastrin > 13.3 pmol/L had a high specificity (91%-100%) and a fair sensitivity (56%-78%) to detect corpus-predominant atrophy. Based on low serum PG-1 and PG-1/PG-2 ratio together as diagnostic criteria, 12.5% of the asymptomatic subjects had corpus-predominant atrophy (0% of those under 25 years and 20.2% over 65 years old). The frequency of gastric atrophy was similar (12% vs 13%) but H pylori infection rate was slightly higher (77% vs 71%) in the high-risk compared to the low-risk counties. Based on their estimated gastric cancer risk, individuals were classified as: low-risk group (no H pylori infection and no atrophy; n = 115; 21.4%); moderate-risk group (H pylori infection but no atrophy; n = 354, 66.0%); and high-risk group (gastric atrophy, with or without H pylori infection; n = 67, 12.5%). The high-risk group was significantly older (mean age: 61.9+/-13.3 years), more frequently men and less educated as compared with the low-risk group. CONCLUSION: We propose to concentrate on an upper gastrointestinal endoscopy for detection of early gastric cancer in the high-risk group. This intervention model could improve the poor prognosis of gastric cancer in Chile.
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Atrofia/diagnóstico , Mucosa Gástrica/patología , Adulto , Anciano , Anciano de 80 o más Años , Atrofia/epidemiología , Chile/epidemiología , Femenino , Gastrinas/sangre , Humanos , Masculino , Persona de Mediana Edad , Pepsinógeno A/sangre , Pepsinógeno C/sangre , Valores de Referencia , Factores de Riesgo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/epidemiologíaRESUMEN
We investigated anatomic alterations and lateralization effect in the mesial temporal lobe structures (amygdala and hippocampus) in epileptic psychosis MRI volumetric measurements. Patients with epileptic psychosis and normal controls were studied. Left hippocampus values were significantly smaller for patients (P<0.001). Hippocampal ratio was significantly greater for patients (P<0.01). Group (patients x normal) was the only factor explaining the statistically significant variation of left hippocampus and hippocampal ratio (P<0.001 and P<0.05). Twenty patients had hippocampal atrophy (4 on the right side, 15 on the left side, and 1 bilateral) associated with mesial temporal sclerosis. These results confirm the existence of anatomic alterations and a left laterality effect in the mesial temporal lobe structures of patients with epileptic psychosis.
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Encéfalo/anomalías , Encéfalo/patología , Epilepsia/psicología , Lateralidad Funcional/fisiología , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/etiología , Adulto , Amígdala del Cerebelo/anomalías , Amígdala del Cerebelo/patología , Atrofia/epidemiología , Atrofia/patología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Epilepsia/diagnóstico , Epilepsia/epidemiología , Femenino , Hipocampo/anomalías , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Variaciones Dependientes del Observador , Trastornos Psicóticos/epidemiología , Reproducibilidad de los Resultados , Esclerosis/epidemiología , Esclerosis/patología , Índice de Severidad de la Enfermedad , Lóbulo Temporal/anomalías , Lóbulo Temporal/patologíaRESUMEN
The aim of this study was to evaluate the frequency and intensity of cerebral atrophy using CT scanning and the possible relation to corticosteroid therapy or disease in systemic lupus erythematosus (SLE) and to analyse the relationships between cerebral atrophy and activity disease and neuropsychiatric manifestations in lupus patients. We studied 107 consecutive SLE patients (American Rheumatology Association 1982 criteria) who were taking steroid drugs at the time and not selected for any particular manifestation (group 1). A complete clinical, neurological and laboratory evaluation was performed. The American College of Rheumatology's classification for neuropsychiatric manifestations and SLE disease activity index for activity were employed. Group 2 comprised 39 non-SLE patients with oral chronic steroid use (1 mg/k/day for more than 3 consecutive months); 50 normal individuals were the controls (group 3). There were no demographic differences between the groups. Brain CT was performed in all individuals and the frequency and the intensity (minimal, moderate and severe) of atrophy analysed, through well-defined measures and indices, by two neuroradiologists. Cerebral atrophy was significantly more frequent in groups 1 and 2 than in group 3, but with no significant difference between groups 1 and 2. The severity of cerebral atrophy was significantly higher in SLE patients (p<0.05), independent of steroid dose or duration of disease. In both groups no patient presented severe atrophy. Lupus patients with and without cerebral atrophy presented neuropsychiatric manifestations and activity disease in a similar proportion. The more frequent neuropsychiatric manifestation in lupus patients with cerebral atrophy was seizures (p<0.05). Chronic glucocorticoid therapy was responsible for cerebral atrophy, with a comparable incidence in both lupus and non-lupus patients compared to age and gender-matched normal subjects untreated with glucocorticoids. The disease activity was not related to cerebral atrophy in group 1 and seizures were the neurologic manifestation related to cerebral atrophy. The severity of the cerebral atrophy was independent of steroid dose, or duration of treatment. Moreover, the disease itself contributes to the severity of this process, but not to the development of cerebral atrophy.
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Corticoesteroides/efectos adversos , Encefalopatías/inducido químicamente , Encefalopatías/epidemiología , Encéfalo/patología , Lupus Eritematoso Sistémico/tratamiento farmacológico , Corticoesteroides/uso terapéutico , Adulto , Distribución por Edad , Análisis de Varianza , Atrofia/inducido químicamente , Atrofia/diagnóstico por imagen , Atrofia/epidemiología , Encéfalo/diagnóstico por imagen , Encéfalo/efectos de los fármacos , Encefalopatías/diagnóstico por imagen , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Modelos Lineales , Lupus Eritematoso Sistémico/diagnóstico , Masculino , Persona de Mediana Edad , Prevalencia , Probabilidad , Medición de Riesgo , Índice de Severidad de la Enfermedad , Distribución por Sexo , Tomografía Computarizada por Rayos XRESUMEN
The premalignant process in the gastric mucosa was studied by gastroscopic surveys of Colombian populations, and the prevalence of superficial gastritis, chronic atrophic gastritis, and intestinal metaplasia was calculated for population samples having a very high gastric cancer risk (Nariño), very low risk (Cartagena), and intermediate risk (Cali). The prevalence of individuals with normal mucosa in successive age groups was used to estimate "depletion" curves, which were taken as indicators of the dynamics of the premalignant process in each community. Differences corresponding to the geographic variation in stomach cancer risk were found: In the high-risk areas of Nariño, around 75% of the population developed some type of gastritis by 45 years of age, whereas in the low- and intermediate-risk population of Cartagena and Cali, the proportion of such lesions did not exceed 50% at age 45 or thereafter. The effect of environmental factors in early life seemed to be important in determining the prevalence of lesions in each population.