Supportive Care in Cancer

, Volume 15, Issue 6, pp 583–595 | Cite as

Laetrile for cancer: a systematic review of the clinical evidence

  • Stefania Milazzo
  • Stephane Lejeune
  • Edzard ErnstEmail author
Review Article



Many cancer patients treated with conventional therapies also try ‘alternative’ cancer treatments. Laetrile is one such ‘alternative’ that is claimed to be effective by many alternative therapists. Laetrile is also sometimes referred to as amygdalin, although the two are not the same.


The aim of this review is to summarize all types of clinical data related to the effectiveness or safety of laetrile interventions as a treatment of any type of cancer.

Materials and methods

All types of clinical studies containing original clinical data of laetrile interventions were included. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 1951), EMBASE (from 1980), Allied and Complementary Medicine (AMED), Scirus, CancerLit, Cumulative Index to Nursing and Allied Health (CINAHL; all from 1982), CAMbase (from 1998), the MetaRegister, the National Research Register, and our own files. For reports on the safety of laetrile, we also searched the Uppsala database. No language restrictions were imposed.


Thirty six reports met our inclusion criteria. No controlled clinical trials were found. Three articles were nonconsecutive case series, 2 were consecutive case series, 6 were best case series, and 25 were case reports. None of these publications proved the effectiveness of laetrile.


Therefore, the claim that laetrile has beneficial effects for cancer patients is not supported by sound clinical data.


Laetrile Amygdalin Cancer Systematic review 



The authors thank Katja Schmidt for her valuable support and the European Commission for having funded the CAM-Cancer project within its fifth framework program.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Stefania Milazzo
    • 1
  • Stephane Lejeune
    • 2
  • Edzard Ernst
    • 1
    Email author
  1. 1.Complementary Medicine, Peninsula Medical SchoolUniversities of Exeter and Plymouth, Institute of Health and Social CareExeterUK
  2. 2.EORTC Data CentreBrusselsBelgium

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