Laetrile treatment for cancer

Area of Science:

• Oncology
• Pharmacology
• Toxicology

Background:

• Laetrile, a semi-synthetic compound related to amygdalin, is promoted for cancer treatment.
• Amygdalin is a cyanogenic glycoside found in apricot kernels and other Prunus species.
• Despite promotion, there is no evidence supporting the efficacy of laetrile or amygdalin for cancer treatment.

Purpose of the Study:

• To evaluate the purported anti-cancer effects of laetrile and amygdalin.
• To assess the potential adverse effects associated with laetrile and amygdalin use.

Main Methods:

• Comprehensive literature search across multiple databases (CENTRAL, MEDLINE, EMBASE, etc.) and registers.
• Inclusion criteria focused on randomized controlled trials (RCTs) and quasi-RCTs.
• Two reviewers screened and assessed studies for eligibility, with no restrictions on time or language.

Main Results:

• Over 200 references were initially identified.
• 63 studies were evaluated in the original review, with an additional 6 in the update.
• Crucially, no studies met the inclusion criteria for evaluating laetrile or amygdalin in cancer treatment.

Conclusions:

• Current clinical data do not support claims of laetrile or amygdalin benefiting cancer patients.
• Significant risks of serious adverse effects, particularly cyanide poisoning, exist with laetrile and amygdalin, especially via oral administration.
• The risk-benefit assessment for laetrile and amygdalin as cancer treatments is unequivocally negative.