I would like to know a few things about cancer.
If a tumour is benign, is it safe to leave it alone?
Are moles or freckles a form of cancer?
Why is panceatic cancer so deadly?
Thanks
All cancers are dangerous, because they will spread if left alone. By definition, a benign tumor grows, but does not spread.
Benign tumors are still dangerous by reason of their growth, cutting off circulation and impeding other bodily functions.
Moles can become melanomas, which is a type of skin cancer and extremely dangerous because it spreads so readily. See a dermatrologist if you have a specific problem.
Pancreatic cancer is also bad because you can’t live without a pancreas. It controls metabolism and digestion. You can live without part or all of a single lung in contrast.
Does this help?
MD here.
Not all cancers are inherently dangerous. Some are so slow growing that it’s best to leave them alone. Many cases of prostate cancer fall into this category. However, it takes an expert to figure out which tumors should be left strictly alone.
Most benign growths can be left alone, unless they’re causing problems like compressing vital organs, etc.
Moles and freckles are not forms of cancer. But some moles and freckles can become cancerous. Just like your colon is not a form of cancer, but some colon cells can become cancerous.
Pancreatic cancer is so dangerous in part because that it generally produces no signs or symptoms until it is quite advanced and has spread to other locations in the body. In addition, most chemo and radiation therapy doesn’t seem to slow down the standard type of pancreatic cancer much at all.
You can live without a pancreas quite well, if you have insulin and digestive enzyme supplements, despite VunderBob’s statements.
There are a few kinds of cancer that are less dangerous than others. The primary example is basal cell carcinoma (BCC), the most common form of skin cancer. Unlike other kinds of skin cancer, BCC rarely metastatizes or kills, but if left untreated, it does grow and can become disfiguring.
It is thought that certain types of prostate cancer are very indolent and can be present for decades without ever causing any major problems or even (until recently) being detectable. However, you wouldn’t want to assume that you had that type, and be wrong.
How dangerous a tumour is depends very much on where a tumour is.
For example, your brain is important, and it is encased in bone, so there isn’t room for much expansion.
A brain tumour can be deadly even if it is benign, simply because if it is big enough it can squeeze the brain enough to shut down a vital area.
I had it in my head that you couldn’t live without a pancreas any more than you could a liver, and it was because they were linked in metabolic regulation.
OK, I can be wrong occasionally, and I’m big enough to admit it. 
Newsweek has a current story about cancer research. Basically, researchers are discovering that there are common genetic defects that can subdivide cancers. So you might have lung cancer of one type while someone else has lung cancer of another type. Medications can be targeted against the particular defects that are present (which is part of why, historically, one person might have responded well while another died despite the same obvious symptoms). Obviously, we’re still at early stages of identifying and targeting these things.
Anyway, the article mentions that pancreatic cancers are more likely to have numerous defects. Medications might shut down two or three defects - enough to kill a cancer with smaller numbers of defects - and yet the pancreas may have two or three others to keep the tumor growing aggressively.
I blame your wrongness on your location at the Gates of Hell. :eek:
C’mon in already!
I’ve been told bladder cancer is also so slow to grow as to be non-dangerous.
My brother in law currently is undergoing chemo for aggressive bladder cancer. Eventually, surgery and at least partial removal (and possibly full removal) of his bladder will happen.
Don’t assume any cancer is slow growing until its been evaluated.
Good analogy. Side question: why are moles & freckles more likely to turn into skin cancer than an average, run-of-the-mill normally colored patch of skin?
Wait … IS it more likely? Is that why we’re supposed to pay more attention to them than to regular skin?
Most malignant melanomas start as new growths, not from pre-existing moles. Also, they are not necessarily caused by the sun- people get them on soles of the feet and in the groin, areas that hardly ever see the sun.
A cell doesn’t become cancerous until many things have gone wrong. There are all sorts of redundant controls that keep cell growth carefully under control. If one of those controls is broken or bypassed by a mutation perhaps nothing will happen. If another control mechanism breaks, you might start to get benign growths. It takes several mutations to cause a cell to divide aggressively as a cancer.
Moles and freckles are patches of cells that have already started to grow abnormally through some sort of mutation, but not very much so they’re normally harmless. Still, they’re one or two mutations closer to becoming cancerous, so they’re much more likely to develop into a melanoma compared to a normal-looking patch of skin.
These are awesome answers by everyone.
Thanks
I wish it was. My Aunt Mary died from bladder cancer that had spread to a large part of her abdominal cavity. It took about two years from the time she was diagnosed.
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