I’ve been wondering for a long time and finally decided to come out and ask…
How does radiation cause tumors and yet they use it in cancer treatment to treat tumors?
Thanks!
Radiation can damage cells. If you concentrate it on a tumor it can kill off tumor cells. If a normal cell is irradiated but not killed, there is a (slight) chance that it can be damaged is such a way as to become cancerous. If enough cells are irradiated in this way chances are that sooner or later one or more will become cancerous.
Radiation kills cells. This is very useful in treating localized, rapidly growing tumors, as cells which grow fast are even more sensitive to radiation than slower-growing cells (such as are found most places in normal tissue, blood being the big exception).
Radiation also injures cells. These injured cells may eventually die off, heal up on their own, or less frequently be altered enough to somewhere down the line turn cancerous.
So it’s a trade-off. Try to kill a known cancer now at the small but real risk of causing a new cancer years or decades later.
QtM, MD
Less appreciated may be that chemotherapy can also lead to cancers down the road. Similar to radiation, chemotherapy kills (rapidly dividing) cells but it also damages the DNA of other cells. Sometimes, such damage leads to cancer.
This is especially the case with chemotherapy that includes so-called “alkylating agents”.