Cancer Treatments?
Why Not Cancer Prevention?

Cancer treatments are what the medical community has to offer cancer patients. So far, cancer is not cured by the best medical knowhow available today; it is treated.

The goal is to give the patient the best quality of life possible for as long as possible.

Since the war on cancer began in 1971 and having spent over forty billion dollars on the war, cancer treatments still consist of surgery, radiation and chemotherapy.

Not much has changed in almost forty years except that the tools and technology of the trade have seen improvements.

There are some new developments on the horizon in both detection and treatment that may lead to actual cures someday.

Several considerations must be taken into account for all cancer treatments.

First is whether or not a target is required. Is the treatment such that it must be focused on a tumor mass as an aiming point?

Second, is it necessary that the microscopic margins of the tumor be tightly controlled? In other words, can sufficient surrounding tissue be removed without causing collateral damage?

Third, is the treatment toxic or have the potential for causing systemic damage.

Fourth, how invasive is the treatment and does it have the potential for recovery complications?

Fifth, does the treatment handle the bulk of a tumor? Does it totally remove the bulk of the tumor? Is it tumorcidal; i.e., kill or remove the entire tumor?

Sixth, is the treatment applicable for all types of cancer? In other words, does one size fit all?

Seventh, is the treatment a one-shot or will frequent and repetitive treatments be required?

In spite of all the considerations mentioned above, surgery is usually the first modality chosen in that it is the one approach that can remove the bulk of the tumor mass.

In reality, one approach is rarely used in cancer treatments. Surgery is combined with chemo or radiation; or chemo and radiation combined without surgery; or surgery and radiation without the chemo; or maybe all three combined.

The paragraphs below detail the pros and cons of each of three cancer treatments currently employed and looks at two others that are gaining ground.

Surgery

Surgery, the granddaddy of cancer treatments can, in many cases, remove the entire bulk of a tumor mass. It is tumorcidal, meaning that the tumor will not grow back if the entire mass and its feeder system is removed.

On the downside, it is the most invasive of cancer treatments, does require a well defined target is not the best approach for control of the microscopic margins of a tumor mass.

A quantum leap is being made in delicate surgery, especially cancer surgery, that will greatly reduce the invasive nature of the operation.

Photo: The patients side cart of the Da Vinci Robotic Surgical System showing the operating arms

With the introduction of the Da Vinci Robotic Surgical System, very complex surgical procedures, such as the prostatectomy, are now minimally invasive with greatly reduced recovery periods.

The system is also being used in heart valve repair, thoracic and abdominal surgery, hysterectomy and other gynecological operations.

The Da Vinci System consists of a surgeon’s console, a patient-side cart with four interactive robotic arms, a high-performance 3D high definition vision system and instruments.

The system scales, filters and translates the surgeon's hand movements into more precise micro-movements of the instruments.

We are seeing the future of surgery unfold before our eyes.

Radiation beats surgery in terms of being non-invasive and has excellent control of the margins of the tumor.

At least it is non-invasive in that cutting into the patient with a knife is not required. It is also tumorcidal in that it will kill the tumor.

The cons are that it requires a definite, well defined target; handles the bulk of a tumor poorly; has many side effects and is limited to one lifetime dose of radiation.

Once that lifetime dose is reached, that site can never be radiated again or tissue necrosis (death) will likely occur.

Radiation energy was measured in rads but now uses the "Gray" as a unit of measure. The ratio between rads and Grays is 100 to one; 5000 rads = 50 Grays which happens to be a typical radiation dosage to a given area.

Handbook of Radiation Oncology: Basic Principles and Clinical Protocols

The definitive book on radiation cancer treatments is found in the"Handbook of Radiation Oncology" from Jones & Bartlett Publishing Company. It can be ordered from Amazon via the link above.

The object is radiation is not to fry the tumor but to injure the DNA to the point that the cell loses its reproductive capability.

Cell death is defined as a loss of ability to replicate. Great care must be taken with low dosage radiation since it can cause a mutation without killing the cell and initiate carcinogenesis; the very thing we are trying to stop.

Photo: Linear accelerator typical of those used in cancer treatment

The linear accelerator is widely used today in radiation cancer treatments. It uses higher radiation but is more focused by making use of a tangential beam that moves in an arc around the patient.

A computer figures out exactly where to shoot, thus sparing surrounding tissue.

Chemo is well suited for handling the micro metastases that may have spread to other locales and no specific target is required; it is systemic.

The "Chemotherapy Drug Manaul" shown below provides a complete, easy-to-use catalogue of over 100 drugs and commonly used drug regimens—both on-and off-label—for the treatment of all the major cancers. Click on the link to Amazon.com for more information on this valuable book.

Physicians' Cancer Chemotherapy Drug Manual: 2009

Being systemic is the downside of chemo; it is systematically toxic and once the treatment is started; it must be followed to completion.

If chemo is stopped before the full course of treatment has been completed, it will almost always fail and the cancer will come roaring back with more resistant cells.

Additionally, chemo handles the bulk of a tumor poorly. Chemo is given intravenously and a major downside is that it is Unlikely to do the job with just one drug.

It usually takes multiple drugs with different toxicity which, hopefully, will provide a synergistic effect while keeping the patient from getting too sick. It is also hard to measure responses with chemo.

In suspected metastasized cancers, adjuvant chemotherapy is used. This means that it is given to a patient that is thought to have metastasized but not proven.

It is used where conditions are such that it would be too dangerous to wait.

The discovery of angiogenesis goes back to 1960 when Dr. Judah Folkman, the father of angiogenesis, noticed that tumors implanted in organs all stopped growing at the exact same size. Eleven years later in 1971 he published his theory that tumors needed a blood supply to grow and that they used some type of signaling to recruit new blood vessels.

As is typical in medicine, new ideas are first dismissed, even ridiculed and Folkman was no exception. It took another ten years before anyone started taking his findings seriously.

Angiogenesis is a physiological process involving the growth of new blood vessels from pre-existing vessels. It is a normal process in growth and development, as well as in wound healing. However, this is also a fundamental step in the transition of tumors from a dormant state to a malignant state.

Tumors induce angiogenesis by secreting various growth factors which can induce capillary growth into the tumor to supply its required nutrients and allowing the tumor to start growing.

Cancerous cells stop producing the anti-VEGF enzyme PKG. Normal cells produce an enzyme, PKG that limits a hormone, beta-catenin, which kick starts angiogenesis. Cancerous cells have learned to stop producing PKG so that there is nothing to block the formation of new blood vessels to the tumor.

Angiogenesis is a necessary and required step for a small harmless cluster of cells about the size of a pin head, to transition to a large tumor. Angiogenesis is also required for the spread of a tumor, or metastasis.

Single cancer cells can break away from an established solid tumor, enter the blood vessel, and be carried to a distant site, where they can implant and begin the growth of a secondary tumor.

Natural and synthetic angiogenesis inhibitors, also called antiangiogenic agents, are being studied in the hope that these chemicals will prevent or slow down the growth of cancer by blocking the formation of new blood vessels.

Bevacizumab (Avastin) was the first angiogenesis inhibitor approved by the FDA. It was proven to delay tumor growth and is being used with other drugs to treat colorectal cancer, some breast cancers and non-small cell lung cancers that have metastasized. The FDA has also approved other drugs with antiangiogenic activity as cancer therapies for multiple myeloma, mantle cell lymphoma, gastrointestinal tumors, and kidney cancer.

Anti-angiogenesis therapy is non-toxic and uses the same Rx for almost all tumors plus no specific target is required. Its downside is that it is currently very expensive and tumor static, meaning it doesn't destroy the primary tumor.

The last of the cancer treatments we will mention is Molecular Rx.

Molecular targeted therapies are a type of cancer treatment that works more directly on cancer cells than do standard chemo treatments.

This approach targets cancer cells very specifically and target only the parts of cells that encourage the abnormal growth of tumors or the blood vessels that encourage tumors to grow. As a result, the damage to normal cells is minimized, thus lowering the severity of side effects.

Molecular Rx or molecular targeted cancer treatments are highly specific, generally non-toxic with no target required. So far they are not universally applicable.

Our cancer coverage will wrap up with where our focus should have been all along, cancer prevention.

Included here for you convenience is a search box for Abe Books. To examine the wide scope of books on Cancer Treatments, just type it in the box and hit "Search". See what happens.

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