In the population-based SURVCAN-3 study reported in The Lancet Oncology, Soerjomataram et al identified cancer survival rates in 32 countries in Africa, Central and South America, and Asia. They found that disparities for many cancer types reflect the standing of countries according to the Human Development Index (HDI).
Study Details
The study involved 1,400,435 cases of 15 major cancer types from 68 population-based cancer registries in 32 countries in Africa, Central and South America, and Asia. Patients were diagnosed between January 2008 and December 2012 and followed for at least 2 years. Age-standardized net survival (survival in which cancer was the only possible cause of death) was calculated, and outcomes were assessed according to country categorization on the HDI (low, medium, high, very high).
Key Findings
Net survival varied substantially among countries and regions, with estimates increasing with increasing HDI category. Across the cancer types, the highest 3-year net survival rate observed in countries in the lowest HDI category was 54.6% for prostate cancer in Côte d’Ivoire, whereas the highest rate in countries in the highest HDI categories was 96.8% for prostate cancer in Israel. Examples of net survival across regions for several of the cancer types analyzed are provided below.
- For breast cancer, 3-year net survival was > 80% in most countries. In Central and South America, estimates ranged from 80.9% in Chile to 90.5% in Costa Rica. However, estimates ranged from 61.7% in Zimbabwe to 87.9% in Kenya in Africa, and from 56.0% in Iran to 93.9% in South Korea in Asia.
- For prostate cancer, more than half of the countries had 3-year net survival close to or above 85%. However, estimates ranged from 46.0% in South Africa to 87.9% in Algeria in Africa, and from 62.1% in China to 96.8% in Israel in Asia.
- For colon cancer, 3-year net survival in Asia ranged from 37.4% in India to 76.9% in South Korea. The highest rate in Africa was in Mauritius (75.7%). Rates were similar across countries and territories in Central and South America, with the highest found in Puerto Rico (67.2%).
- Lung cancer survival was low across regions and HDI levels, with a median 3-year net survival of 18.4% among all countries. The highest estimated 3-year net survival rates by region were Algeria (39.3%) in Africa, Costa Rica (30.9%) in Central and South America, and Israel (33.0%) in Asia.
The investigators stated, “Three distinct groups with varying outcomes by country and HDI dependent on cancer type were identified: cancers with low median 3-year net survival (< 30%) and small differences by HDI category (eg, lung and stomach); cancers with intermediate median 3-year net survival (30% to 79%) and moderate difference by HDI (eg, [cervical and colorectal]), and cancers with high median 3-year net survival (≥ 80%) and large difference by HDI (eg, breast and prostate).”
They concluded, “Disparities in cancer survival across countries were linked to a country’s developmental position and the availability and efficiency of health services. These data can inform policymakers on priorities in cancer control to reduce apparent inequality in cancer outcome.”
Isabelle Soerjomataram, PhD, of the Cancer Surveillance Branch, International Agency for Research on Cancer, Lyon, France, is the corresponding author for The Lancet Oncology article.
Disclosure: The study was funded by Tata Memorial Hospital, Martin-Luther-University Halle-Wittenberg, and International Agency for Research on Cancer. For full disclosures of the study authors, visit thelancet.com.
