title: Mortality and survival patterns of childhood lymphomas: geographic and age-specific patterns in Southern-Eastern European and SEER/US registration data.
abstract: Childhood (0-14 years) lymphomas, nowadays, present a highly curable malignancy compared with other types of cancer. We used readily available cancer registration data to assess mortality and survival disparities among children residing in Southern-Eastern European (SEE) countries and those in the United States. Average age-standardized mortality rates and time trends of Hodgkin (HL) and non-Hodgkin (NHL; including Burkitt [BL]) lymphomas in 14 SEE cancer registries (1990-2014) and the Surveillance, Epidemiology, and End Results Program (SEER, United States; 1990-2012) were calculated. Survival patterns in a total of 8918 cases distinguishing also BL were assessed through Kaplan-Meier curves and multivariate Cox regression models. Variable, rather decreasing, mortality trends were noted among SEE. Rates were overall higher than that in SEER (1.02/106), which presented a sizeable (-4.8%, P = .0001) annual change. Additionally, remarkable survival improvements were manifested in SEER (10 years: 96%, 86%, and 90% for HL, NHL, and BL, respectively), whereas diverse, still lower, rates were noted in SEE. Non-HL was associated with a poorer outcome and an amphi-directional age-specific pattern; specifically, prognosis was inferior in children younger than 5 years than in those who are 10 to 14 years old from SEE (hazard ratio 1.58, 95% confidence interval 1.28-1.96) and superior in children who are 5 to 9 years old from SEER/United States (hazard ratio 0.63, 95% confidence interval 0.46-0.88) than in those who are 10 to 14 years old. In conclusion, higher SEE lymphoma mortality rates than those in SEER, but overall decreasing trends, were found. Despite significant survival gains among developed countries, there are still substantial geographic, disease subtype-specific, and age-specific outcome disparities pointing to persisting gaps in the implementation of new treatment modalities and indicating further research needs.
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, University of Athens, Athens, Greece.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Karalexi
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, University of Athens, Athens, Greece.
authors.forename: Marios K
authors.initials: MK
authors.lastname: Georgakis
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, University of Athens, Athens, Greece.
authors.forename: Nick
authors.initials: N
authors.lastname: Dessypris
authors.affiliation: National Cancer Registry of Ukraine, National Institute of Cancer, Kiev, Ukraine.
authors.forename: Anton
authors.initials: A
authors.lastname: Ryzhov
authors.affiliation: Childhood Cancer Sub-registry of Belarus, Belarusian Research Center for Pediatric Oncology, Hematology and Immunology, Minsk, Belarus.
authors.forename: Anna
authors.initials: A
authors.lastname: Zborovskaya
authors.affiliation: Bulgarian National Cancer Registry, National Oncology Hospital, Sofia, Bulgaria.
authors.forename: Nadya
authors.initials: N
authors.lastname: Dimitrova
authors.affiliation: Institute of Public Health of Serbia, Belgrade, Serbia.
authors.forename: Snezana
authors.initials: S
authors.lastname: Zivkovic
authors.affiliation: Izmir Cancer Registry, Izmir Hub, Izmir & Hacettepe University Institute of Public Health, Izmir, Turkey.
authors.forename: Sultan
authors.initials: S
authors.lastname: Eser
authors.affiliation: North Region Cancer Registry of Portugal (RORENO), Portuguese Oncology Institute of Porto, Porto, Portugal.
authors.forename: Luis
authors.initials: L
authors.lastname: Antunes
authors.affiliation: Croatian National Cancer Registry, Croatian National Institute of Public Health, Zagreb, Croatia.
authors.forename: Mario
authors.initials: M
authors.lastname: Sekerija
authors.affiliation: Cancer Registry of Republic of Slovenia, Institute of Oncology, Ljubljana, Slovenia.
authors.forename: Tina
authors.initials: T
authors.lastname: Zagar
authors.affiliation: Central Region Cancer Registry of Portugal (ROR-Centro), Portuguese Oncology Institute of Coimbra, Coimbra, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Bastos
authors.affiliation: Cyprus Cancer Registry-Health Monitoring Unit, Ministry of Health, Nicosia, Cyprus.
authors.forename: Anna
authors.initials: A
authors.lastname: Demetriou
authors.affiliation: Department of Health Information and Research, Malta National Cancer Registry, Pieta, Malta.
authors.forename: Domenic
authors.initials: D
authors.lastname: Agius
authors.affiliation: Regional Cancer Registry of Iasi, National Institute of Public Health, Iasi, Romania.
authors.forename: Margareta
authors.initials: M
authors.lastname: Florea
authors.affiliation: Regional Cancer Registry of Cluj, Oncological Institute "Ion Chiricuta", Cluj-Napoca, Romania.
authors.forename: Daniela
authors.initials: D
authors.lastname: Coza
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, University of Athens, Athens, Greece.
authors.forename: Evdoxia
authors.initials: E
authors.lastname: Bouka
authors.affiliation: Oncology Department, "Mitera" Children's Hospital, Athens, Greece.
authors.forename: Helen
authors.initials: H
authors.lastname: Dana
authors.affiliation: Second Department of Pediatrics, Aristotelian University of Thessaloniki, AHEPA General Hospital, Thessaloniki, Greece.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Hatzipantelis
authors.affiliation: Department of Pediatric Hematology and Oncology, Hippokration Hospital, Thessaloniki, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Kourti
authors.affiliation: Haematology-Oncology Unit, First Department of Pediatrics, Athens University Medical School, "Aghia Sophia" Children's Hospital, Athens, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Moschovi
authors.affiliation: Department of Pediatric Haematology-Oncology, "Aghia Sophia" Children's Hospital, Athens, Greece.
authors.forename: Sophia
authors.initials: S
authors.lastname: Polychronopoulou
authors.affiliation: Department of Pediatric Hematology-Oncology, University of Crete, University Hospital of Heraklion, Heraklion, Greece.
authors.forename: Eftichia
authors.initials: E
authors.lastname: Stiakaki
authors.affiliation: Department of Pediatric Hematology-Oncology, "Pan. & Agl. Kyriakou" Children's Hospital, Athens, Greece.
authors.forename: Apostolos
authors.initials: A
authors.lastname: Pourtsidis
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, University of Athens, Athens, Greece.
authors.forename: Eleni Th
authors.initials: ET
authors.lastname: Petridou
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053208:Kaplan-Meier Estimate; D008223:Lymphoma / Q000453:epidemiology / Q000401:mortality*; D008297:Male; D011159:Population Surveillance; D016016:Proportional Hazards Models; D012042:Registries; D018426:SEER Program; D014481:United States / Q000453:epidemiology
keywords: SEER; Southern-Eastern Europe; cancer registration; childhood lymphoma; mortality; survival