PART II
Chapter 3
Modern Technologies in Radiotherapy (Cont'd)
3. Improvement of radiotherapy by
using radioprotectors
Radioprotection is another important approach
in radiotherapy. Basically, a therapeutic agent, radioprotector, is
administered to a patient before the patient is treated by radiotherapy. In
other words, radioprotectors protect normal tissues against radiation-induced
side effects. Ideally, radioprotectors produce or stimulate certain biological
reactions/products which then counteract the adverse effects caused by
radiation.
Unfortunately, there has not been any
significantly improved radioprotector since the discovery and approval of a
popular broad-spectrum radioprotective drug, amifostine (Fig. 2.3), by the FDA.
Interestingly, amifostine was originally approved to reduce the cumulative renal toxicity associated
with repeated administration of cisplatin in patients with advanced ovarian
cancer and non-small cell lung cancer. However, while nephroprotection was
observed, amifostine also formed chelation with cisplatin and reduced its
anticancer activity. Therefore, its indication for chemoprotection in
cisplatin treatment in non-small cell lung cancer was withdrawn in 2005.
Fig. 2.3. Structure of amifostine (WR2721) and its
metabolite
More details about amifostine and
other radioprotectors are described in Part III.
© Jiajiu Shaw, 2021
Disclaimer: This blog is written solely for informational purposes. It does not constitute the practice of any medical, nursing or other medical professional health care advice, diagnosis, or treatment. All contents posted are extracted from the book, "SIDE EFFECTS OF CHEMOTHERAPY AND RADIOTHERAPY", prepared by Dr. Jiajiu Shaw, Dr. Frederick Valeriote, and Dr. Ben Chen.
