Saturday, February 25, 2012

Cancer Part I

     This blog is not a general review of cancers, but rather simple facts about all cancers in general. I was motivated to write this blog as a result of my volunteer work with Gilda's Club of Northern New Jersey. It really is true that only a person who has cancer can really understand and relate to another person who has or had cancer. There still are a lot of untrue beliefs floating around, and this blog is an attempt to correct some of them.

     First, the only trustworthy site is WWW.NATIONAL CANCER INSTITUTE.GOV.  This is the only totally unbiased reference available on the internet. It lists all the cancers by organ, and then breaks the organ cancer down into subtypes (e.g. nodal non-Hodgkins lymphoma). It lists the standard treatment, secondary treatments, etc. and also refers to a site where you can find a list of clinical trials. Any website published by a hospital or any other institution is biased by institutional philosophy----e.g. the  chairman of the Urology Dept. at John Hopkins published a book about the virtues of using surgery to treat prostate cancer, so if they have a patients' website, you might see some bias. But the NCI has no such axe to grind.

     Second, all doctors want to heal their patients. There are really NO SECRETS in medicine. In these days of Oprah, etc., if a doctor had a new cure for cancer, he/she would scream it from the rooftops, get on Oprah and Jay Leno, be on talk shows, etc. We all want to cure all our patients, and we are constantly seeking new treatments via journal article, conferences, etc. (And The National Enquirer is not now and never will be a refereed medical journal.)

     Each major hospital has a weekly conference open to all its oncologists and other interested physicians. In a large city, there are monthly cancer conferences to which all hospitals send a doctor-delegate. Finally there are quarterly divisional meetings as well as annual conferences on cancer to which all doctors are invited. We also have publications by the Mayo Clinic, etc., which are distributed to all interested doctors. So again, there are no secrets about treating cancer. If a doctor had a new method, he/she would publicize it so as to become famous as well as rich.

     The only people who really can  judge a physician's brains and abilities are the residents who work with him/her especially if they have operated with the surgeon in question. No one else, including your next door neighbor, your best friend, and your aunt Sally know anything about the doctor in question. When I was a medical resident at Columbia , I asked all the surgical residents who the best general surgeons, breast surgeons, vascular surgeons, gynecologists, oncologists, chest surgeons, heart surgeons, orthopedic surgeons, neuro surgeons, urological surgeons, etc. were, and I referred my patients only to those surgeons. In fact, I convinced my older partner to switch away from the surgeon to whom he usually referred his patients.

     The most certain method of treating/eliminating cancer is to surgically remove the mass before it has metastacized. This means taking out the tumor en bloc, with a good margin (i.e. non-cancerous tissue)  around it. The surgeon will generally also remove or sample nearby lymph notes to look for local spread. This is why it is so difficult to treat brain, pancreatic, or ovarian cancer. Note: I said difficult, not impossible. As a rule, it is difficult to get a good margin around a brain tumor because the tumor has spread its tentacles (like a "crab"  aka "cancer" in stellar constellations) into vital tissues that control memory or the contraction of muscles.And unlike most organs, neither the ovary nor the pancreas is surrounded by a protective sheath, as is the colon, or the liver, so these two cancers spread locally very easily, although as a rule they are detected while they are still contained within the abdominal cavity.

     Surgery is often followed by radiation therapy and/or chemotherapy. The idea is to get any few cells that have escaped (micro-metastases) beyond the organ before the surgery. Of course with any cancer based in the bone marrow such as the leukemias, the lymphomas and the myelomas, surgery is usually of no use. All these treatments rest on the same principles: cancer cells have a higher metabolic rate and multiply faster than nearby normal cells in the same organ. We have known for almost 100 years that cancer cells have a higher metabolic rate; this was determined by showing that they utilize oxygen at a higher rate that normal cells. This is also the basis for the PET scan, which replaces oxygen-16 with radioactive oxygen-17 in a sugar molecule, and determining which cells absorb and use this sugar the fastest.

     All radiation and chemotherapy modes (with a few exceptions, such as we have with l-asparaginase in one type of leukemia, or the use of monoclomal antibodies to kill other cancers) can kill all cells, and our  hope is that the more rapidly dividing cancer cells will be killed faster than normal tissue. This is why treatment schedules are carefully monitored as to dosage (mg/kg), time, and frequency. You want the normal tissue to be able to recover between treatments.

     I have barely scratched the surface of this topic, and have deliberately omitted discussion of the role of your immune system in controlling or killing cancer and cancer cells, because then the blog would have been much too long.


   

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