Chemoradiation Side Effects - A Primer

For any cancer treatment(s) there seem to be endless lists of side effects. The truth is that chemo is poison and the radiation is also meant to inflict damage. Both are done to damage and/or kill tissues within the body. The intent is to target the cancer, the bad cells and diseased tissues, but currently there is no way for chemo or radiation to know the difference between bad and good. As previously noted, rapid growth or more accurately rapid cell division is the main indicator but it is not a trait limited only to cancer.

Radiation is literally easier to aim as it can be focused on the tumor site but the beams go through everything in front of and behind and to either side of the tumor as well. Our bodies are packed and the pieces parts are connected or touch each other. For the moment, we can't really isolate the parts we know are bad, we can only pick the region and zap it, hoping to get just outside the diseased area to catch all the bad and do the least harm to the good.

Chemotherapy goes through the blood stream, ie, the whole body. Chemo drugs actually get into the DNA of rapidly dividing cells to disrupt the cell division. That's pretty serious widespread action at a seriously basic level. A few drugs hit the cells while resting in between cell-division, but most hit the cells while actually dividing or while the cells are in the process of replicating genes in preparation for division.

The ultimate differences between the effects on good cells and bad, as I understand them...
1) Normal cells are usually resting and not constantly growing or dividing like cancer cells, at least in adults. Normal cells tend to aggressively divide only when replacements or repairs are needed.
2) Normal cells communicate better with each other to trigger division for replication and/or repair when other similar cells have been damaged or died. But, cancer cells have not mastered this communication, so when a cancer cell is damaged, it just dies. The other cancer cells do not recognize the need to work extra to replace it. After all, they're working overtime already just dividing for themselves.
2) Chemo is much more effective on non-resting cells, being able to sneak in the door while the DNA is actively in play for replication or division.

Side effects come from damage to normal cells. Side effects usually go away after the chemo stops and the normal cells have had time to repair and replenish their numbers. Conversely, the cancer cells are just dead, which is of course the point of it all, and what makes the side effects acceptable.

Double-Checking My Team

First, I have to say that I was very satisfied with explanations I recieved from my team members and all my questions were answered fully and confidently. Even so, I went to the internet and googled all the new terms I was learning, as much as I could find out about my type and stage of cancer, all the treatments and the drug names, and I waded through proper medical info as well as patient forums to investigate my team's plan to vanquish my particular cancer.

Fortunately, I was repeatedly assured that my team had chosen the most aggressive and currently accepted game plan. It was an overwhelming second opinion and I was content to follow the prescribed actions. I have continued throughout to reverify, just in case. It seems only wise to do so.