Side-effects are results of treatment that are not part of the wanted effect. In other words when a person is given chemo or radiotherapy the wanted effect is to shrink the tumour or prevent recurrence. The treatment, though, will cause other effects, which can include a lowered immune system as well as a range of physical or emotional problems. For a good book to explain these effects and how to get through them, see The Chemotherapy and Radiation Therapy Survival Guide by Judith McKay and Nancee Hirano on Amazon.com or Amazon.co.uk
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