Background: Previous population-based incidences of childhood cancer in Thailand were achieved by
extrapolating from data limited to a small number of cancer registries, not from the whole country. In addition,
survival of childhood cancer patients is often described in specialized hospitals and/or institutions, but not in
the general population. Methods: All children aged 0–15 years who were newly diagnosed as having cancer
were registered from 18 treatment centers during 2003-5 and classified into 12 diagnostic groups according to
the International Classification of Childhood Cancer. Incidences were calculated by a standard method and
survival was investigated using the ThaiPOG (Thai Pediatric Oncology Group) population-based registration
data. Overall survival was calculated by the Kaplan Meier method. Results: In the study period (2003-5) 2,792
newly diagnosed cases of childhood cancer were registered, with mean and median ages of 6.5 (SD=0.13) and 5.0
(0-14) years, respectively. The age-peak was between 1 and 4 years and the age-standardized rate (ASR) was 74.9
per million. Leukemia was the most common cancer (N=1421, ASR 38.1) followed by lymphoma (N=266, ASR
6.4) and neoplasms of the central nervous system (CNS, N=246, ASR 6.3). The follow-up duration totaled 101,250
months. The death rate was 1.11 per 100 person-months (95%CI: 1.02 -1.20). The 5-year overall survival was
54.9% (95%CI: 53.0%-56.9%) for all cancers. The respective, 5-year overall survival for (1) acute lymphoblastic
leukemia (ALL), (2) acute non-lymphoblastic leukemia (ANLL), (3) lymphoma, (4) retinoblastoma, (5) renal
tumors, (6) liver tumors, (7) germ cell tumors, (8) CNS tumors, (9) neuroblastoma, (10) soft tissue tumors and
(11) bone tumors were (1) 64.5%, (2) 35.1%, (3) 59.5%, (4) 73.1%, (5) 70.4%, (6) 44.5%, (7) 70.6%, (8) 41.7%,
(9) 33.6%, (10) 50.1%, and (11) 33.7%. Conclusions: The incidence of childhood cancer is lower than in western
countries. Respective overall survival for ALL, lymphoma, renal tumors, liver tumors, retinoblastoma, soft tissue
tumors is lower than those reported in developed countries while for CNS tumors, neuroblastoma and germ cell
tumors the figures are comparable.