Forum Moderators: Robert Charlton & goodroi
ALL is an acronym for Acute Lymphoblastic Leukemia; the most common Leukemia in children.
As you are doing a site search with just one word (which is complicated by being a stopword) that happens to be an acronym, the options are there to help people search more effectively.
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Of course, your site: stipulation means that if you drilldown on your query you may not find anything; apart from an urge to donate to a worthy charity.