Incidence trends and patterns of breast cancer in Sri Lanka: an analysis of the national cancer database.

BACKGROUND: A gradual decline in the incidence of breast cancer is documented in developed countries especially over last two decades, while in developing countries the incidence continues to rise. We conducted this study to examine trends in incidence of breast cancer in a developing country, Sri Lanka. METHODS: A retrospective cohort evaluation of patients with breast cancer during 2001-2010 was performed using population based data from the Sri Lanka National Cancer Registry. Trends in incidence were analysed using Joinpoint regression analysis. RESULTS: The age standardized incidence of female breast cancer in Sri Lanka appears to have increased from 17.3 per 100,000 in 2001 (95% confidence interval [95% CI] 16.5-18.2) to 24.7 per 100,000 in 2010 (95% CI 23.7-25.7); a 1.4-fold increase (p < 0.05) with an estimated annual percentage change (EAPC) of 4.4 (95% CI 3.3-5.5). Highest incidence of breast cancer was seen among women of 60 to 64-year age group which has increased from 68.1 to 100.2 per 100,000 over this period (EAPC 4.6%, 95% CI 3.9-5.2, p < 0.001 for trend). A substantially greater increase was observed among women older than 50 years (from 50.4 to 76.9 per 100,000; EAPC 5.5, 95% CI 4.1-7.0, p < 0.05) compared with women younger than 50 years (from 32.0 to 39.6 per 100,000; EAPC 2.3, 95% CI 1.1-3.5, p < 0.05). CONCLUSIONS: A gradual but a significant increase in the incidence of female breast cancer is observed in Sri Lanka. A rapid rise in the breast cancer incidence among post-menopausal women appears to be the major contributor towards this increase. Improving cancer data collection appears to have been a contributor to the observed increase. However, an inherent increase is also likely as differential rates of increase were observed by age groups. Further research is needed to identify the reasons for the observed increase which may help with future cancer control efforts in Sri Lanka.

Incidence and histological patterns of thyroid cancer in Sri Lanka 2001-2010: an analysis of national cancer registry data.

BACKGROUND: An increasing incidence of thyroid cancer is observed in many developed countries. Increasing incidence may also reflect better reporting or increased diagnostic scrutiny. We conducted this study to examine trends in thyroid cancer incidence and histological patterns in Sri Lanka. METHODS: A retrospective cohort evaluation of patients with thyroid cancer during 2001-2010 was performed using population based data published from the Sri Lanka National Cancer Registry. Trends in incidence and histological patterns were analysed by age and gender. RESULTS: The age-standardized incidence of thyroid cancer increased from 2.44 per 100,000 in 2001 (95% confidence interval [95% CI]: 2.21-2.67) to 5.16 per 100,000 in 2010 (95% CI: 4.85-5.47); a 2.1-fold increase (p < 0.05 for trend). A greater part of this increase is attributable to increase in incidence of papillary thyroid cancer, which increased from 1.64 to 3.61 per 100,000; a 2.2-fold increase (p < 0.05 for trend). Follicular cancer showed lesser, yet a significant increase from 0.56 to 0.95 per 100,000 (p < 0.05). Other varieties of thyroid cancer showed no significant increases in incidence. Trends in the increases in incidence of papillary cancer in females showed a much greater increase compared with males (from 2.45 to 5.60 per 100,000, a 2.28-fold increase in females compared with from 0.82 to 1.55; a 1.89-fold increase in males, p < 0.001). Highest incidence of papillary cancer was observed in 30-39-year age group, which has increased from 5.56 to 12.9 per 100,000; a 2.32-fold increase (p < 0.001). CONCLUSIONS: The increasing incidence of thyroid cancer in Sri Lanka is predominantly due to the increasing incidence of papillary cancers. These trends may reflect increased detection and better reporting, although an inherent increase in the incidence is the likely main contributor. Further studies including tumour stage and mortality may help answer these questions.