What can we learn from geographical comparisons of childhood cancer survival?

Global surveillance of trends in cancer survival 2000-14 (CONCORD-3): analysis of individual records for 37 513 025 patients diagnosed with one of 18 cancers from 322 population-based registries in 71 countries

BACKGROUND

In 2015, the second cycle of the CONCORD programme established global surveillance of cancer survival as a metric of the effectiveness of health systems and to inform global policy on cancer control. CONCORD-3 updates the worldwide surveillance of cancer survival to 2014.

METHODS

CONCORD-3 includes individual records for 37·5 million patients diagnosed with cancer during the 15-year period 2000-14. Data were provided by 322 population-based cancer registries in 71 countries and territories, 47 of which provided data with 100% population coverage. The study includes 18 cancers or groups of cancers: oesophagus, stomach, colon, rectum, liver, pancreas, lung, breast (women), cervix, ovary, prostate, and melanoma of the skin in adults, and brain tumours, leukaemias, and lymphomas in both adults and children. Standardised quality control procedures were applied; errors were rectified by the registry concerned. We estimated 5-year net survival. Estimates were age-standardised with the International Cancer Survival Standard weights.

FINDINGS

For most cancers, 5-year net survival remains among the highest in the world in the USA and Canada, in Australia and New Zealand, and in Finland, Iceland, Norway, and Sweden. For many cancers, Denmark is closing the survival gap with the other Nordic countries. Survival trends are generally increasing, even for some of the more lethal cancers: in some countries, survival has increased by up to 5% for cancers of the liver, pancreas, and lung. For women diagnosed during 2010-14, 5-year survival for breast cancer is now 89·5% in Australia and 90·2% in the USA, but international differences remain very wide, with levels as low as 66·1% in India. For gastrointestinal cancers, the highest levels of 5-year survival are seen in southeast Asia: in South Korea for cancers of the stomach (68·9%), colon (71·8%), and rectum (71·1%); in Japan for oesophageal cancer (36·0%); and in Taiwan for liver cancer (27·9%). By contrast, in the same world region, survival is generally lower than elsewhere for melanoma of the skin (59·9% in South Korea, 52·1% in Taiwan, and 49·6% in China), and for both lymphoid malignancies (52·5%, 50·5%, and 38·3%) and myeloid malignancies (45·9%, 33·4%, and 24·8%). For children diagnosed during 2010-14, 5-year survival for acute lymphoblastic leukaemia ranged from 49·8% in Ecuador to 95·2% in Finland. 5-year survival from brain tumours in children is higher than for adults but the global range is very wide (from 28·9% in Brazil to nearly 80% in Sweden and Denmark).

INTERPRETATION

The CONCORD programme enables timely comparisons of the overall effectiveness of health systems in providing care for 18 cancers that collectively represent 75% of all cancers diagnosed worldwide every year. It contributes to the evidence base for global policy on cancer control. Since 2017, the Organisation for Economic Co-operation and Development has used findings from the CONCORD programme as the official benchmark of cancer survival, among their indicators of the quality of health care in 48 countries worldwide. Governments must recognise population-based cancer registries as key policy tools that can be used to evaluate both the impact of cancer prevention strategies and the effectiveness of health systems for all patients diagnosed with cancer.

FUNDING

American Cancer Society; Centers for Disease Control and Prevention; Swiss Re; Swiss Cancer Research foundation; Swiss Cancer League; Institut National du Cancer; La Ligue Contre le Cancer; Rossy Family Foundation; US National Cancer Institute; and the Susan G Komen Foundation.

Is there a socioeconomic variation in survival from renal tumours in children and young people resident in northern England (1968-2012)?

BACKGROUND

Despite strong evidence of a social gradient in cancer survival among UK adults, studies in children and young people remain inconclusive and have not included renal tumours. This study investigated the relationship between socioeconomic status and survival from renal tumours among children and young people.

PROCEDURE

Kaplan-Meier estimation and Cox regression were used to analyse survival for all 209 renal tumours in children and young people (0-24 years) diagnosed 1968-2012 and registered by a specialist population-based registry. Sociodemographic and clinicopathologic variables, including paternal occupation at birth, were also analysed.

RESULTS

No significant disparity in overall renal tumour and Wilms tumour (WT) survival was observed according to paternal social class [p=0.988 and 0.808, respectively]. The strongest predictor of survival was stage, with late stage (III-IV) disease having a 4-fold higher risk of death compared to early stage (I-II) disease [p<0.001]. Similarly, high mortality-risk was seen for late stage WT in children aged 0-14 years (Hazard Ratio=6.37; 95% CI=2.60-15.59).

CONCLUSIONS

This study did not detect a significant social gradient in renal tumour survival. The identification of tumour stage as a strong predictor of survival irrespective of age, necessitates the development of appropriate public health interventions that target early diagnosis and treatment.

The burden of rare cancers in the United States

There are limited published data on the burden of rare cancers in the United States. By using data from the North American Association of Central Cancer Registries and the Surveillance, Epidemiology, and End Results program, the authors provide information on incidence rates, stage at diagnosis, and survival for more than 100 rare cancers (defined as an incidence of fewer than 6 cases per 100,000 individuals per year) in the United States. Overall, approximately 20% of patients with cancer in the United States are diagnosed with a rare cancer. Rare cancers make up a larger proportion of cancers diagnosed in Hispanic (24%) and Asian/Pacific Islander (22%) patients compared with non-Hispanic blacks (20%) and non-Hispanic whites (19%). More than two-thirds (71%) of cancers occurring in children and adolescents are rare cancers compared with less than 20% of cancers diagnosed in patients aged 65 years and older. Among solid tumors, 59% of rare cancers are diagnosed at regional or distant stages compared with 45% of common cancers. In part because of this stage distribution, 5-year relative survival is poorer for patients with a rare cancer compared with those diagnosed with a common cancer among both males (55% vs 75%) and females (60% vs 74%). However, 5-year relative survival is substantially higher for children and adolescents diagnosed with a rare cancer (82%) than for adults (46% for ages 65-79 years). Continued efforts are needed to develop interventions for prevention, early detection, and treatment to reduce the burden of rare cancers. Such discoveries can often advance knowledge for all cancers. CA Cancer J Clin 2017. © 2017 American Cancer Society. CA Cancer J Clin 2017;67:261-272. © 2017 American Cancer Society.

Cure rates of childhood acute lymphoblastic leukemia in Lithuania and the benefit of joining international treatment protocol

BACKGROUND

Childhood acute lymphoblastic leukemia (ALL) represents the largest group of pediatric malignancies with long-term survival rates of more than 80% achieved in developed countries. Epidemiological data and survival rates of childhood ALL in Lithuania were lacking. Therefore, the aim of this study was to analyze the population-based long-term treatment results of childhood ALL in Lithuania during 1992-2012.

MATERIALS AND METHODS

Data of all 459 children with T-lineage and B-cell precursor ALL treated in Lithuania from 1992 to 2012 were collected and analyzed. Results were compared among four time-periods: 1992-1996 (N=132), 1997-2002 (N=136), 2003-2008 (N=109) and 2009-2012 (N=82).

RESULTS

The incidence of childhood ALL in Lithuania was 3.2-3.6 cases per 100000 children per year during the study period. Five-year probability of event-free survival increased from 50%± 4% in 1992-1996 to 71%± 4% in 2003-2008 (P<0.001). Five-year cumulative incidence of relapses reduced from 27%± 4.5% in 1992-1996 to 14%± 3.6% in 2003-2008 (P=0.042). After introduction of high-dose methotrexate of 5 g/m(2), cumulative incidence of CNS-involving relapses reduced from 17%± 3.9% in 1992-1996 to 1%± 1.0% in 2003-2008 (P<0.001). Trend for further improvement in survival was seen in 2009-2012 when Lithuania joined international the Nordic Society of Pediatric Hematology and Oncology (NOPHO) ALL-2008 treatment protocol.

CONCLUSIONS

Cure rates of childhood ALL in Lithuania are improving steadily and are now approaching those reported by the largest international study groups. The reasons for such a positive effect are both better financial support for treatment of children with cancer in Lithuania and international collaboration with joining international treatment protocol for childhood ALL.

Survival from childhood cancer in northern England, 1968-2005

Background:

Cancer is the second most common cause of death in children in the developed world. The study investigated patterns and trends in survival from childhood cancer in patients from northern England diagnosed 1968–2005.

Methods:

Five-year survival was analysed using Kaplan–Meier estimation for four successive time periods. Cox regression analysis was used to explore associations with age and demographic factors.

Results:

The study included 2958 cases (1659 males and 1299 females). Five-year survival for all cancers improved significantly from 39% in 1968–1977 to 79% in 1998–2005 (P<0.001). Five-year survival for leukaemia increased from 24% to 81% (P<0.001), lymphoma from 46% to 87% (P<0.001), central nervous system tumours from 43% to 73% (P<0.001), bone tumours from 21% to 75% (P<0.001), soft tissue sarcoma from 30% to 58% (P<0.001) and germ cell tumours from 59% to 97% (P<0.001). Survival was worse for cases of acute lymphoblastic leukaemia (P<0.001) and astrocytoma (P<0.001) aged 10–14 years compared with 0–4-year olds.

Conclusion:

There were marked improvements in survival over a 38-year time span. Future work should examine factors that could influence further improvement in survival such as diagnosis delays.