This patient-friendly article is about chemotherapy drug, Paclitaxel or, Taxol a treatment for non-small cell lung cancer, head and neck cancer, melanoma, ovarian and breast cancer, which although it is effective at decreasing the size of tumours, increases the release of cancer cells into the blood stream causing more metastases.
Taxol is a colourless liquid administered by drip. It is a compound extracted from the bark and needles of the Pacific yew tree, Taxus brevifolia, and has strong ’cytotoxic’ abilities, inhibiting cell division. Put simply, it is a poison and causes cancer cells to die by self-destruction - blocking the function of the apoptosis inhibitor protein Bcl-2 (B-cell Leukaemia 2) found normally in cancer cells. It can have serious side-effects and its benefits are often over claimed.
In the USA Doctors tell patients with breast cancer that it has an effect in less than 3 per cent of cases.
Taxol is manufactured by Bristol-Myers Squibb and was approved by the FDA in 1993. Sanofi-Aventis has repeatedly advertised Docetaxel (Taxotere) as more modern and effective, although they are both taxanes with seemingly little to choose between them in terms of effectiveness.
Taxol is often given with other drugs - for example, carboplatin.
Side effects can include: a reduced white blood cell count, hair loss, numbness and or tingling in hands or feet, painful muscles and joints. Occasionally, it can slow the heart rate and may temporarily affect the liver. It is important that people taking Taxol avoid grapefruit (the fruit, the fruit juice) as it can concentrate or reduce the effectiveness of the drug.
Can Taxol cause cancer to spread?
Cancer Watch (Feb 2010) included the story 'Can cancer drugs spread breast cancer?' In it we covered a controversial paper (extract 6014) presented at the 27th Annual San Antonio Breast Cancer Symposium. German researchers from the Friedrich-Schiller University in Jena have found that the action of Taxol causes a massive increase in metastases around the body, which could appear as cancer some years after treatment had finished.
This research has been confirmed several times since that presentation. For example in 2014, a study from the Southern Illinois School of Medicine showed that Taxol promoted drug resistance and metastasis while simultaneously inhibiting tumour growth.
Put simply, Taxol is pretty good at reducing the size of tumours. However, when it breaks down the tumour, the number of cancer cells from the tumour entering the blood stream is greatly increased. The net effect is that, for a while, doctors report a great success with the tumour shrunk. However, the numbers of released cancer cells make for a much greater spread of the cancer at a later stage.
Two studies are very clear that, as a result, there is no increase in overall survival time (1, 2).
The drug is now off patent, and the truth is coming out.
A 2017 study from Ohio State Medical School showed that people treated with Paclitaxel had much higher levels of Atf3, which causes metastases, than those who took other drugs. Atf3 causes 'intravasation' which increases cancer cell spread from the tumour by increasing 'gateways' into the blood stream.
Go to: Paclitaxel, yet again, shown to spread cancer
Go to: 10 ways to improve your chemotherapy and reduce side-effects
References
- P. Rastogi et al, J Clin Oncology, 26, 778-785 (2008)
- L Gianni et all, J Clin Oncology 27, 2474-2481 (2009)
*************
Other articles that you may find interesting are:
- A diet for Chemotherapy
- Immunotherapy overview
- A to Z Guide to Complementary Therapies
Go to: Return to the CANCERactive drug list