# Exactly how does cancer kill? (looking for scientific answeres) **URL:** \ **Category:** Factual Questions\ **Created:** [June 10, 2003, 8:26am UTC](https://boards.straightdope.com/t/exactly-how-does-cancer-kill-looking-for-scientific-answeres/180816 "2003-06-10T08:26:13Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![lite](https://avatars.discourse-cdn.com/v4/letter/l/b5ac83/32.png) [@lite](https://boards.straightdope.com/u/lite)\ **Post date:** [June 10, 2003, 8:26am UTC](https://boards.straightdope.com/t/exactly-how-does-cancer-kill-looking-for-scientific-answeres/180816/1 "2003-06-10T08:26:13Z")
As anyone that knows me is aware, I recently lost my mother to acute adult leukemia. To compound this, I lost my father to no fewer than 5 forms of cancer (though his official cause of death was heart attack which I understand is common in cancer). Neither smoked (adding that so the [Truth.com](http://Truth.com) brigade doesn’t start in) and both went from diagnosis to death in less than 6 months. Here’s my query. I understand cancer is a mutation of cells, malignant meaning it spreads and corrupts other healthy cells, but exactly what does cancer do tothe body to kill it? I have a feeling I didn’t word this right, but let’s start with this. ---
**Author:** ![Skip](https://avatars.discourse-cdn.com/v4/letter/s/ebca7d/32.png) [@Skip](https://boards.straightdope.com/u/Skip)\ **Post date:** [June 10, 2003, 9:26am UTC](https://boards.straightdope.com/t/exactly-how-does-cancer-kill-looking-for-scientific-answeres/180816/2 "2003-06-10T09:26:33Z")
I am not a doctor but my understanding is that cancerous cells basically overrun the organ where they are situated, starving it of nutrients and causing the organ to cease functioning. Cancer affecting the lungs would cause the lungs to slowly lose their ability to extract oxygen from the air causing difficulty breathing in the patient. The same would apply in other organs where cancer is present. ---
**Author:** ![curly\_chick](https://avatars.discourse-cdn.com/v4/letter/c/7ba0ec/32.png) [@curly\_chick](https://boards.straightdope.com/u/curly_chick)\ **Post date:** [June 10, 2003, 10:35am UTC](https://boards.straightdope.com/t/exactly-how-does-cancer-kill-looking-for-scientific-answeres/180816/3 "2003-06-10T10:35:00Z")
A healthy body replaces old, worn out and damaged cells as needed. If you imagine a cut on your finger, the scab forms and the new skin grows to fill the gap. On a cut, the skin regrows from the jagged edges into the centre of the cut where all the new edges meet up. Once they do meet up, they stop growing. This is called contact inhibition. Cancer cells have their contact inhibition “sensors”, if you like, switched off and so they keep on growing and physically crush the organ they are in, preventing it from doing its job properly. For cancer cells in connective tissue, such as blood or bone, this has far reaching consequences because the cancer cells have more chance to travel within the body, causing secondary cancers or metastases in organs which were not part of the original problem. ---
**Author:** ![enigmatic](https://avatars.discourse-cdn.com/v4/letter/e/898d66/32.png) [@enigmatic](https://boards.straightdope.com/u/enigmatic)\ **Post date:** [June 10, 2003, 12:25pm UTC](https://boards.straightdope.com/t/exactly-how-does-cancer-kill-looking-for-scientific-answeres/180816/4 "2003-06-10T12:25:33Z")
It depends on the type of cancer. The cancerous tissue can physically interfere with the natural functions of the body as the previous poster’s have described. In addition they can cause illness by consuming resources which are needed elsewhere in the body (a tumour can require a lot of oxygen and nutrients) and can release angiogenic factors which create the nessecary vasculature to divert blood flow. They can also retain the function of the tissue that they derived from, for example a tumour forming from glandular tissue can release an excess of hormones into the body causing a whole set of extra problems. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [June 10, 2003, 6:26pm UTC](https://boards.straightdope.com/t/exactly-how-does-cancer-kill-looking-for-scientific-answeres/180816/5 "2003-06-10T18:26:25Z")
But the sequence of events at the very end often goes like this: The runaway growth of the tumor eventually outgrows the vascularization, so the middle of the tumor does not get good enough circulation. The tumor starts to die, perhaps at the center where blood vessels have the hardest time keeping up. The dead tissue in the tumor starts to decompose, to become necrotic. Having an ever-enlarging mass of tissue more and more of which is dead and decomposing puts a tremendous strain on the body by weeping infection and toxins into the bloodstream, until one of the critical organs is so compromised by this environment that it stops. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [June 10, 2003, 6:32pm UTC](https://boards.straightdope.com/t/exactly-how-does-cancer-kill-looking-for-scientific-answeres/180816/6 "2003-06-10T18:32:53Z")
From this thread entitled, [“How does cancer kill you”](http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=166148&highlight=cancer), I quote myself: > [@](#): > > \*\*Cancer kills in many ways. Depending on the specific type, all or some of the following may apply: > > 1. Cancer, at its primary site can cause lethal problems eg. lung cancer blocking a bronchus (breathing tube) leading to pneumonia, eg. cancer of the bile ducts blocking off the liver > > 2. Cancer can spread locally and kill, eg. a lung tumor that eats it way into a blood vessel or into the heart lining > > 3. Cancer can spread far beyond its primary site and do damage there, eg. breast cancer spreading to the liver and causing liver failure, or eg. breast cancer spreading diffusely through the lungs, or eg. lung cancer spreading to the brain > > 4. Cancer weakens the body, sometimes in obvious ways such as malnutrition, and sometimes in subtler ways such as inhibiting the immune system. In either case, infections result and are much more severe than in “normal” individuals. > > 5. Cancer makes the blood clot more readily. Blood clots kill. (The association between cancer and clots is quite common but not generally appreciated, IMO, by lay people) > > (N.B. Both #4 and #5 are made worse by the immobility of advanced cancer patients) > > 1. Cancer replaces the bone marrow causing fewer white blood cells and/or platelets to be produced. Infection and/or bleeding results. > > 2. Cancer can leads to bizarre, unpredictable, and sometimes mysterious effects in the body, eg. lung cancer causing “Lou Gehrig’s Disease”, eg. kidney cancer causing high blood calcium levels, eg. myeloma (a type of bone marrow cancer) causing breakdown of the nerves in the body (neuropathy), eg. lymph cancer leading to kidney failure > > I’m sure there are even more mechanisms. \*\*