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Laetrile for cancer: a systematic review of the clinical evidence

Supportive Care in Cancer volume 15, pages 583–595 (2007)Cite this article

Abstract

Background

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.

Objective

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.

Results

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.

Conclusion

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

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Acknowledgement

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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Authors and Affiliations

  1. Complementary Medicine, Peninsula Medical School, Universities of Exeter and Plymouth, Institute of Health and Social Care, 25 Victoria Park Road, Exeter, EX2 4NT, UK

    Stefania Milazzo & Edzard Ernst

  2. EORTC Data Centre, Avenue E. Mounier 83, bte 11, 1200, Brussels, Belgium

    Stephane Lejeune

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  1. Stefania Milazzo
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  2. Stephane Lejeune
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Correspondence to Edzard Ernst.

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Milazzo, S., Lejeune, S. & Ernst, E. Laetrile for cancer: a systematic review of the clinical evidence. Support Care Cancer 15, 583–595 (2007). https://doi.org/10.1007/s00520-006-0168-9

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Keywords

  • Laetrile
  • Amygdalin
  • Cancer
  • Systematic review