Acute lymphoblastic leukaemia (ALL) is rare. It is estimated that 6550 new cases of ALL and 1330 associated deaths will occur in the US in 2024.[9]National Cancer Institute. Surveillance, epidemiology, and end Results (SEER) Program. Cancer stat facts: leukemia - acute lymphocytic leukemia (ALL). 2024 [internet publication].
https://seer.cancer.gov/statfacts/html/alyl.html
Median age at diagnosis is 17 years.[9]National Cancer Institute. Surveillance, epidemiology, and end Results (SEER) Program. Cancer stat facts: leukemia - acute lymphocytic leukemia (ALL). 2024 [internet publication].
https://seer.cancer.gov/statfacts/html/alyl.html
More than half of all cases (53%) occur in those aged under 20 years.[9]National Cancer Institute. Surveillance, epidemiology, and end Results (SEER) Program. Cancer stat facts: leukemia - acute lymphocytic leukemia (ALL). 2024 [internet publication].
https://seer.cancer.gov/statfacts/html/alyl.html
Peak incidence occurs at 1-4 years (78 per 1 million [2017-2021]); incidence decreases to 25 cases per 1 million by 10-14 years (2017-2021).[10]National Cancer Institute. SEER Explorer: All cancer sites combined. Recent trends in SEER age-adjusted incidence rates, 2000-2020. 2023 [internet publication].
https://seer.cancer.gov/statistics-network/explorer/application.html?site=1&data_type=1&graph_type=2&compareBy=sex&chk_sex_3=3&chk_sex_2=2&rate_type=2&race=1&age_range=1&hdn_stage=101&advopt_precision=1&advopt_show_ci=on&hdn_view=0&advopt_show_apc=on&advopt_display=2#resultsRegion0
ALL is slightly more common in males than females.[9]National Cancer Institute. Surveillance, epidemiology, and end Results (SEER) Program. Cancer stat facts: leukemia - acute lymphocytic leukemia (ALL). 2024 [internet publication].
https://seer.cancer.gov/statfacts/html/alyl.html
Incidence in the US is highest in Hispanic people (26 per 1 million [2017-2021]) and lowest in non-Hispanic black people (10 per 1 million [2017-2021]).[10]National Cancer Institute. SEER Explorer: All cancer sites combined. Recent trends in SEER age-adjusted incidence rates, 2000-2020. 2023 [internet publication].
https://seer.cancer.gov/statistics-network/explorer/application.html?site=1&data_type=1&graph_type=2&compareBy=sex&chk_sex_3=3&chk_sex_2=2&rate_type=2&race=1&age_range=1&hdn_stage=101&advopt_precision=1&advopt_show_ci=on&hdn_view=0&advopt_show_apc=on&advopt_display=2#resultsRegion0
B-ALL (arising from B lymphoid progenitors) accounts for approximately 75% of cases, with the remainder being predominantly T-ALL (arising from T lymphoid progenitors).[4]Bene MC, Castoldi G, Knapp W, et al. Proposals for the immunological classification of acute leukaemias. European Group for the Immunological Characterization of Leukemias (EGIL). Leukemia. 1995 Oct;9(10):1783-6.
http://www.ncbi.nlm.nih.gov/pubmed/7564526?tool=bestpractice.com
[5]Terwilliger T, Abdul-Hay M. Acute lymphoblastic leukemia: a comprehensive review and 2017 update. Blood Cancer J. 2017 Jun 30;7(6):e577.
https://www.nature.com/articles/bcj201753
http://www.ncbi.nlm.nih.gov/pubmed/28665419?tool=bestpractice.com
Mixed-phenotype (B-cell and T-cell) ALL may occur, but is exceptionally rare.