Yupa Sumitsawan

Cancer survival in Africa, Asia, and Central America: a population-based study

BACKGROUND Population-based cancer survival data, a key indicator for monitoring progress against cancer, are not widely available from countries in Africa, Asia, and Central America. The aim of this study is to describe and discuss cancer survival in these regions. METHODS Survival analysis was done for 341 658 patients diagnosed with various cancers from 1990 to 2001 and followed up to 2003, from 25 population-based cancer registries in 12 countries in sub-Saharan Africa (The Gambia, Uganda), Central America (Costa Rica), and Asia (China, India, Pakistan, Philippines, Saudi Arabia, Singapore, South Korea, Thailand, Turkey). 5-year age-standardised relative survival (ASRS) and observed survival by clinical extent of disease were determined. FINDINGS For cancers in which prognosis depends on stage at diagnosis, survival was highest in China, South Korea, Singapore, and Turkey and lowest in Uganda and The Gambia. 5-year ASRS ranged from 76-82% for breast cancer, 63-79% for cervical cancer, 71-78% for bladder cancer, and 44-60% for large-bowel cancers in China, Singapore, South Korea, and Turkey. Survival did not exceed 22% for any cancer site in The Gambia; in Uganda, survival did not exceed 13% for any cancer site except breast (46%). Variations in survival correlated with early detection initiatives and level of development of health services. INTERPRETATION The wide variation in cancer survival between regions emphasises the need for urgent investments in improving awareness, population-based cancer registration, early detection programmes, health-services infrastructure, and human resources. FUNDING Association for International Cancer Research (AICR; St Andrews, UK), Association pour la Recherche sur le Cancer (ARC, Villejuif, France), and the Bill & Melinda Gates Foundation (Seattle, USA).

Visual Functions in Locally Advanced Nasopharyngeal Carcinoma Patients after External Beam Radiation

Purpose: To evaluate the effects of radiation to the anterior visual pathway in locally advanced nasopharyngeal carcinoma (NPC) patients after low energy photon external beam radiation. Design: A cross-sectional, observational case series. Methods: Fifty- one patients treated with the same radiotherapy were assessed in visual acuity (VA), color vision, visual field (VF), and contrast sensitivity. The patients with post radiation interval of ≤ 3 years were defined as group 1, of > 3 years as group 2, and healthy volunteers as control group 3. The visual functions were analyzed between the three groups. Results: One patient in group 1 developed radiation-induced optic neuropathy (RION) with decreased VA, color vision defect, decreased contrast sensitivity, and VF defect. No RION was detected in group 2. There was no statistical significance in color vision defect (P = 0.303) or mean contrast sensitivity (P = 0.235) between the three groups. There was statistical significance in mean contrast sensitivity value (P = 0.044) between the irradiated and non-irradiated group. Conclusions: This study reported the acceptable incidence of RION in 1.96% of locally advanced NPC patients after external beam radiotherapy. Significant decrease in contrast sensitivity was the subclinical anterior visual pathway abnormality, observed among the irradiated group. Monitoring subjective and objective visual changes is helpful for irradiated patients in detecting and assessing treatment for minimizing long term devastating results on the visual conditions.