Editor’s note: The Jewish Link welcomes medical oncologist Dr. Alfred Neugut to our pages, where he will share his thoughts and knowledge about cancer.
Cancer has become a major part of our environment; almost a cultural touchstone. It is omnipresent in the lay press; most of us know someone who has it or has died from it; many of us are fearful of it; and yet accurate knowledge about what it is, how to deal with it when it arises in our lives and how to prevent it are truly hard to come by.
I have spent more than four decades as a lab researcher, oncologist, cancer epidemiologist and prevention researcher immersed in cancer and hope that I can impart some of my own thoughts (I emphasize that these will be my own thoughts—not necessarily shared by others) on this dreaded group of diseases. I would caution that this information is just that, informational, and should not be used directly for clinical purposes—readers should always have the opportunity to discuss their cancer-related questions and concerns with a trusted health care provider.
Perhaps the best place to start a discussion on cancer is to ask what exactly is cancer, or as I might phrase it, what defines malignancy? Most cells in the body have the capacity to evolve over time into malignancy, which may manifest itself as a malignant tumor. The characteristic that defines a malignant cell is the loss of growth control or regulation. Thus, cancer cells have lost their growth inhibition. When you cut yourself, the skin cells on the two sides of the cut start to reproduce and proliferate in order to fill in the gap and heal the wound. Over a few days, they will gradually grow towards each other until the two sides of the cut touch each other and seal the wound. At that point, the cells in the skin will stop proliferating—somehow they understand that there is no further need for growth and reproduction. This is normal, or benign, cell growth. However, a malignant cell does not recognize that there is no further need for reproduction and will continue to proliferate; indeed, the malignant or cancer cell will proliferate infinitely and overgrow its limits.
If you put normal cells in a Petri dish, they will grow until they have covered the surface of the Petri dish and created a single layer or monolayer of cells—they will then stop growing. That is normal cellular behavior. If you add a carcinogen or cancer-causing chemical to the dish, you may transform one or more of the cells into a malignant cell. That cell will then continue to grow and reproduce, forming a heaped up mass in the dish.
Frequently, cancer cells also grow more rapidly than their normal counterparts. This is also a common feature of cancer cells, but not necessary—it is the loss of growth inhibition that is the defining property. Many other properties may also occur in cancer cells. But it is the unrestricted growth that is the main thing. In conjunction with this, if a malignancy occurs in someone, it also has the potential to be fatal over time, even if it may appear to be a slow-growing and indolent tumor. That goes along with the loss of growth inhibition. So when there are malignant cells, they keep on growing unless stopped in some way, and they are potentially fatal—again, unless removed or inhibited in some way. The common treatments we are familiar with—surgery, radiation therapy, chemotherapy, hormonal therapy—are all intended to intervene in that process.
Cancers as a group are the second leading cause of mortality in the US at this time, after heart disease. Almost 50% of men can expect to get cancer at some point in their lives while almost 40% of women will (we can discuss in a future article the reasons for this discrepancy).
Nonetheless, while I have been generalizing about cancer, the intelligent reader will appreciate that there are dozens of types of cancer and possibly hundreds of subtypes of cancer—breast, colorectal, prostate, myeloma, Hodgkin lymphoma, pancreatic, etc.—and that each has its own story in terms of etiology, epidemiology, natural history, management and prognosis, even though they do all share the definition of malignancy with which I started out our discussion.
Certainly at least one major strategy in cancer treatment has been a major effort to interfere with cancer proliferation, a major part of the underpinnings of classical chemotherapy. In some cases, this has met with stunning success, but in other cases less so. Again, this requires a more detailed discussion than this brief introduction can permit and I will save it for a future article.
In the meantime, I look forward to joining the pages of The Jewish Link and hope that I can offer some insights in a clear and readable way.
Alfred I. Neugut, MD, PhD, is a medical oncologist and cancer epidemiologist at Columbia University Irving Medical Center/New York Presbyterian and Mailman School of Public Health in New York.
This article is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis or treatment, and does not constitute medical or other professional advice. Always seek the advice of your qualified health provider with any questions you may have regarding a medical condition or treatment.
