Bone Metastasis - New Information

Bone Metastasis - New Information on Bone Cancer of Contents of paper

Bone Metastasis - New Information on Bone Cancer

Bones are among the more common and likely places for cancer cells to begin their growth cycle, so it is relevant to research bones and cancer. In this paper some new information that has come available through science research will be reviewed; some of this information gives hope for those with bone cancer and other cancers.

First, it is fair to ask, what is metastasis? The Merriam-Webster online dictionary (www.m-w.com) defines "metastasis" as "change of position, state, or form"; also metastasis is "...the spread of a disease-producing agency (as cancer cells) from the initial or primary site of disease to another part of the body; also: the process by which such spreading occurs."

What then is bone metastasis? It is bone cancer, according to the American Cancer Society (www.cancer.org),and metastatic cancer is a kind of cancer that has spread from the part of the body where it had its origin (that is called its "primary site") to different parts of the body. The way the cancer gets from its primary site to the rest of the body is that cells "break away" from the tumor and go through the bloodstream (or "lymphatic channels") to elsewhere in the body. While en route to the rest of the body in the bloodstream, cancerous cells can, and do, wind up just about anywhere, the American Cancer Society (ACS) reports. It should be noted though that "fewer than 1 in 10,000 cancer cells survive circulation to create a new tumor" (www.oralcancerfoundation.org).

The very act of that spreading is called metastasis, and ACS goes on to say that even though the cancer has spread to a new location like the lungs, for example, if it started in the breast, it is still breast cancer. Meanwhile, the most common cause of pain in people with cancer is bone metastasis, which can "also cause bones to break," and can cause "high calcium levels in the blood," as calcium is released from damaged bones. And while it is common for cancers that started in bones to move to other areas of the body, cancers that began elsewhere are known to commonly spread to bones; "breast, prostate, lung, kidney and thyroid cancers are most likely to spread to bones," and the part of the skeleton most often affected by bone metastasis is the spine.

The spine (vertebrae) in fact, is the site of bone metastasis in 74% of the cases of bone cancer involvement, according to a research article (Barrick 2006) published by the journal Supportive Care. Other places in the body where bone metastasis occurs is in the pelvic bones (70 of the cases), the ribs (65% of the cases), the upper extremities (48% of the cases) and in the sternum (in 43% of the cases of bone metastasis).

The Supportive Care article was reporting on a symposium in Boston, Massachusetts, during which Dr. Richard Loyd explained that "worldwide, over four million individuals will experience bone metastasis," which is the third most common place for metastasis to be located. It is perfectly normal for bones to be going through both "destruction" and "formation" - which is called the "normal remodeling cycle of bone." However, the "vicious cycle of bone destruction common with metastatic disease" actually originates when tumor cells secrete "excessive amounts of paraneoplastic hormones." Those hormones then activate "osteoclasts" which destroy bones, but in reaction to the osteoclasts, the bone produces certain proteins (like interleukin-6), which, unfortunately, "further enhance tumor growth," and the cycle is complete.