Toxicity of anti-cancer drugs: the imaging findings to watch out for in common cancers

Abstract A multitude of drugs are used for the treatment of various types of cancers. They consist of conventional cytotoxic agents and newer targeted agents. Both types of agents produce a variety of side effects by their effect on normal cells of the body. Regardless of whether they produce any symptoms or not, a proportion of these side effects can be visualised on imaging and their identification is crucial for guiding further management. While some of the adverse effects are mild and tolerable, many others require dose reduction and even withdrawal of the drug. A few of these manifestations may resemble tumour progression or recurrence on imaging. Therefore, appropriate knowledge regarding the imaging manifestations of the adverse effects caused by the chemotherapeutic agents used for various types of cancers is an integral part of onco-radiology practice. In this review, the common adverse effects of various anti-cancer drugs have been described based on the type of malignancy in which they occur, rather than based on the organ affected. This would allow the radiologist to look for common side effects while reading the scan of a patient with a specific cancer.