Cancers were classified to twelve groups, according to the International Classification of Childhood Cancer (ICCC) [1]. Malignant neoplasms (cancers) were defined as those belonging to all diagnostic groups (I–XII) in the ICCC classification with behaviour code 3 (primary malignant neoplasms), plus those belonging to diagnostic groups III (CNS and miscellaneous intracranial and intraspinal neoplasms) and Xa (Intracranial and intraspinal germ cell tumours) with behaviour code 0/1 (benign neoplasms and those of uncertain or unknown behaviour).

One patient might be included in incidence analyses multiple times, depending on the number of cancers with which he/she was diagnosed.

Mortality data show the most common causes of death among childhood cancer patients according to the International Classification of Diseases ICD-10 [2], namely the following diagnosis groups:

  • all malignant neoplasms (C00–C97),
  • malignant neoplasms of bone and articular cartilage (C40-C41),
  • malignant neoplasms of connective and soft tissue (C47, C49),
  • malignant neoplasms of brain, spinal cord and other parts of the central nervous system (C70–C72),
  • non-Hodgkin lymphoma (C82–C86),
  • leukaemias (C91–C95).

From the legislative point of view, a person who has reached the age of 18 is considered as an adult in the Czech Republic. Likewise, the World Health Organization (WHO) defines a child as an individual under the age of 18. In the Czech Republic, the age limit – defined arbitrarily by health insurance companies – is 19 years of age. Until the age of 19, therefore, health insurance companies reimburse all care provided by paediatric oncology departments [2]. For this reason, the entire portal deals with cancers diagnosed in patients up to the age of 19 years.


  1. Steliarova-Foucher E, Stiller C, Lacour B, Kaatsch P. International Classification of Childhood Cancer, third edition. Cancer 2005; 103(7): 1457–1467.
  2. ICD-10: International Statistical Classification of Diseases and Related Health Problems, 10th Revision. Updated on 1 January 2020.
  3. Bajčiová, V., Štěrba, J., Tomášek, J. a kol.: Nádory adolescentů a mladých dospělých. Grada Publishing a.s., Praha 2011, 400 s. ISBN 978-80-247-3554-2.