Special Report on Laetrile: The NCI Laetrile Review. Results of the National Cancer Institute's Retrospective Laetrile Analysis

The National Cancer Institute's retrospective review, undertaken in response to public pressure, solicited case records showing objective benefit from laetrile by mailing requests to 385,000 physicians and 70,000 other health professionals and by contacting pro-laetrile groups directly. Despite an estimated 70,000 Americans having used laetrile by that point, only 93 cases were submitted; 26 were excluded for insufficient documentation. A panel of 12 oncologists, blinded to which treatment each abstracted record described, evaluated 160 courses of treatment (68 laetrile, 68 conventional chemotherapy, 24 no-treatment) drawn from the remaining and comparison records. The panel judged only six laetrile courses to have produced a response (two complete, four partial). The report's abstract concludes the results allow no definite conclusions supporting laetrile's anti-cancer activity. PMID 683212 confirmed via PubMed/NCBI eutils esummary and Crossref DOI resolution; abstract wording per EXA-indexed abstract text, not independently re-fetched from a directly loaded PubMed page (PubMed's page presented a cookie-consent interstitial to automated fetch during this research session).