Place of birth and risk of gallbladder cancer in India.

CONTEXT: Within India, the incidence of gallbladder cancer (GBC) is characterized by marked geographical variation; however, the reasons for these differences are unclear. AIMS: To evaluate the role of place of birth, length of residence, and effect of migration from high‑ to low‑risk region on GBC development. SETTINGS AND DESIGN: Population‑based cancer registries (PBCRs); case–control study. SUBJECTS AND METHODS: Data of PBCRs were used to demonstrate geographical variation in GBC incidence rates. A case–control study data examined the role of birth place, residence length, and effect of migration in etiology of GBC. STATISTICAL ANALYSIS: Rate ratios for different PBCRs were estimated using Chennai Cancer Registry as the reference population. Odds ratios (ORs) for developing GBC in a high‑risk region compared to a low‑risk region and associated 95% confidence interval (CI) were estimated through unconditional logistic regression models using case–control study. RESULTS: GBC shows marked variation in incidence with risk highest in Northeast regions and lowest in South India. OR of 4.82 (95% CI: 3.87–5.99) was observed for developing GBC for individuals born in a high‑risk region compared to those born in a low‑risk region after adjusting for confounders. A dose–response relationship with increased risk with increased length of residence in a high‑risk region was observed (OR lifetime 5.58 [95% CI: 4.42–7.05]; Ptrend ≤ 0.001). The risk persisted even if study participant migrated from high‑ to low‑risk region (OR = 1.36; 95% CI: 1.02–1.82). CONCLUSIONS: The present study signifies the importance of place of birth, length of stay, and effect of migration from high‑ to low‑risk region in the development of GBC. The data indicate role of environmental and genetic factors in etiology of disease.

Rural urban differences in breast cancer in India .

Context: Breast cancer incidence rates are high in developed countries and much lower in less developed countries including India. Aims: The aim of the following study is to compare breast cancer incidence rates in rural, urban and metro regions of India and to estimate risk of developing breast cancer associated with residence in a rural area. Settings and Design: Descriptive and analytical study design. Materials and Methods: We extracted age adjusted incidence rate from 26 population-based cancer registries and data from hospital-based case-control study to estimate rate and risk ratio for developing breast cancer in an urban region compared with a rural residence. Statistical Analysis: The rate ratios and 95% confidence interval (CI) for developing breast cancer in the urban and metro region compared with rural registry of Barshi were estimated. The odds ratio (OR) and 95% CI for developing breast cancer in women residing in a rural region was estimated by fitting unconditional logistic regression using hospital-based case-control study data. Average annual percentage change in most recent 15 years (1996-2010) for Barshi (rural), Aurangabad (urban), and Mumbai (metro) cancer registry was obtained by fitting a log-linear model using joint point regression. Results: Living first 20 years of life in a rural area reduces the risk of breast cancer (OR = 0.65, 95% CI: 0.56-0.76). Conclusions: The current study demonstrates that lifestyle operative in a rural area is protective against risk of developing breast cancer.

Early detection of cervical cancer with visual inspection methods: a summary of completed and on-going studies in India

La India es un país de alto riesgo de cáncer cervical, donde se presentan cerca de la cuarta parte de los casos del total mundial (126 000 casos incidentes y 71 000 muertes durante 2000). La tasa de incidencia estandarizada por edad se encuentra en el rango de 16 a 55 por 100 000 mujeres en diferentes regiones con tasas particularmente altas en áreas rurales. El control del cáncer cervical por detección temprana y tratamiento es una prioridad del Programa Nacional de Control de Cáncer y, desafortunadamente, no hay programas organizados de tamizaje citológico en este país. La infraestructura técnica y financiera para organizar tamizaje en este tipo de cáncer, ha promovido la inspección visual como una potencial alternativa de la citología cervical en la India. Se investigan cuatro tipos de opciones de detección visual de neoplasia cervical: a) inspección a ojo desnudo sin la aplicación de ácido acético, opción ampliamente conocida como downstaging; b) inspección de ojo desnudo después de la aplicación de ácido acético de 3 a 5 por ciento (VIA); c) VIA usando un dispositivo de aumento (VIAM); d) inspección visual después de la aplicación de yodo-lugol (VILI). Se ha mostrado que el Downstaging ha sido pobremente sensible y específico para detectar neoplasia cervical y no es considerado ampliamente como una prueba de tamizaje conveniente para cáncer cervical. VIA, VIAM y VILI son frecuentemente investigados en estudios de corte transversal multicéntricos (sin verificación de sesgo), en los que se evalúan simultáneamente la citología y las pruebas del VPH; los resultados de esas investigaciones estarán disponibles próximamente. Estos estudios proveerán información valiosa sobre el desarrollo de pruebas comparativas para detectar lesiones de alto grado precursoras de neoplasia cervical, y cáncer invasor. Los resultados de los análisis de los datos de dos estudios previos indicaron una sensibilidad aproximada de 93.4 por ciento y una especificidad de 85.1 por ciento para VIA en la detección de CIN 2-3 o lesiones invasoras, comparadas con las de citología con 72.1 por ciento y 91.6 por ciento de sensibilidad y especificidad, respectivamente. La eficacia de VIA para la reducción de la incidencia y la mortalidad de cáncer cervical y su costo-efectividad están siendo actualmente investigadas en dos ensayos de intervención aleatorizados controlados en población de la India. Uno de esos estudios es un ensayo con cuatro brazos que establece la eficacia...