The Retrospective Analysis of Pediatric Acute Leukemia Cases between 1980–2003: Hacettepe Experience.

Leukemia constitutes 25–30% of all pediatric malignancy cases. The epidemiologic and demographic characteristics of this group of patients are important not only for determination of the prognostic factors, but also the risk factors. In this study, 683 patients under 16 years of age who were diagnosed with acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML) between January 1980-July 2003 in Hacettepe University, Pediatric Hematolgy Division are analyzed retrospectively. Besides the epidemiologic characteristics including age, sex, geographic distiribution; the type of disease, clinical presentation, physical examination and laboratory findings on admission and the survival and prognosis relationships are also evaluated in order to determine the disease properties of our country. ALL patients have recieved St. Jude Total XI until 1997, and after 1997 they are treated by St. Jude Total XIII protocol. AML patients have been treated by AML 1995 and AML 1998 protocols. The study group includes 548 (80.2%) ALL and 135 (19.8%) AML cases. Two thirds of the all acute leukemia cases are males in both ALL and AML cases. The median age at diagnosis is 62 months for ALL and 108 months for AML patients. ALL is more common among 1–5 year old group; AML is more common among adolescent age group. The incidence of hematologic malignancies increases suddenly in 1997 and 1998 and then showes a decline later. The hematologic malignancy cases who have been admitted to our clinic is most commonly living in the northern and southeastern parts of Turkey. 50% of ALL and AML patients presents with the complaints of fever and pallor. Bone pain is significantly more common in ALL patients. Median time between onset of syptoms and diagnosis is 30 days for both ALL and AML patients. Lymphadenopathy is present in almost half of ALL and AML patients at diagnosis. Hepatomegaly (72.4% vs 50.4%) and splenomegaly (53.8% vs 36.3%) are more commonly observed in ALL then AML patients (p<0.001). The central nervous system (CNS) involvement is present in 5.8% of ALL and 5.9% of AML patients. There is no statisticaly significant difference between ALL and AML patients in terms of bone, mediastinial and CNS involvements. The most common cytogenetical abnormality in ALL patients is hypodiploidy. 25.4% of ALL and 43.7% of AML patients have relapsed subsequently. The most common type of relaps is seen in bone marrow in both ALL and AML cases, however CNS relaps is seen more commonly among ALL patients (31% vs 4%). Fatality rates of ALL and AML are 20.1% and 56.3%, respectively. The fatality rate of AML is significantly higher than ALL. The CNS involvement at diagnosis and sex have no influnce on the fatality rates; on the other hand the presence of relaps for ALL and AML groups and L3 subtype, being less then 1 year old at diagnosis for ALL cases have a negative effect on fatality rates. Also the fatality rates of ALL patients who have been diagnosed before 1997 and recieved St. Jude Total XI protocol has higher fatality rates then who have been diagnosed after 1997 and recieved St. Jude Total XIII (23.3% vs 14.1%). The collection of the cancer data throughout the country is crucial for the determination of the distribution and risk factors of our country. The best way of cancer data collection is development of cancer recording systems and analyzing these data for the determination of distribution and risk factors of patients with hematologic malignancies.