Could Bisphonates save women from Breast Cancer chemotherapy?
Bisphonates are drugs that strengthen your bones. These bone drugs, as they are often called, are used to treat osteoporosis patients and people with multiple myeloma, a cancer of the white cells that weakens bone tissue. Now, research is showing that their use may well prevent recurrence in cancers like breast cancer. And if that turns out to be the case, bisphonates could be a new cancer treatment and even replace the need for certain breast cancer chemotherapy drugs.
Oestrogen-driven Breast Cancer
Women with oestrogen positive breast cancer typically receive several general chemotherapy drugs and surgery to remove the lump. Then they may well be given 5 years of Tamoxifen treatment, followed by three years of an Aromatase inhibitor like Arimidex.
The initial drugs aim to check the cancer’s growth prior to surgery. The Tamoxifen aims to block receptor sites on healthy cell walls, from attack by dangerous oestrogens like oestradiol, and then the Aromatase Inhibitors aim to cut production of oestrogen in the body. All these drugs are covered more fully in our A to Z guide to cancer drugs, click here.
Oestrogen is also involved in the density of the bone tissue, and women on Aromatase Inhibitors can suffer osteoporosis.
A couple of months ago, regular readers of icon’s Cancer Watch research centre will have noticed some research where women who were treated with bisphonates (an injection every 6 months) actually had an improved rate of survival from breast cancer - by about a third.
Bisphonates may block some breast cancer spread
When oestrogen-driven breast cancers (and indeed, many cancers) spread, cells are fired off from the tumour and they often go to the bone or bone marrow. Here they cause a weakening, which in turn causes growth factors to be produced. And these growth factors are used by the cancer to aid its own growth. Bisphonates seem capable of blocking all this.
There have actually been several research studies done on this issue and the effectiveness of this strategy seems dose-dependent. (In other words, it may be that it only works above certain levels). However, if the findings can be confirmed, it looks like women with oestrogen-driven breast cancer may need less chemotherapy drugs and bisphonates could, instead, prove their best friend.
Other cancers too!
Of course, it is not just breast cancer patients that may benefit. Many cancers are now known to be driven by the female sex-hormone oestrogen, and not just female cancers. Research has shown that some colon cancers, lung cancers and even prostate and testicular cancers can be oestrogen driven. Blocking the production of the stimulating hormone in the bone may be an important step in treatment programmes, rather that using general chemotherapy that merely attacks all rapidly dividing cells, whether they be cancer cells, intestinal cells, hair or nail cells.
In 2010 there will be the results of a trial involving 3000 women with breast cancer using a stronger Bisphonate, Zometa. Other bisphonates include the drugs Clondronate (Bonefos), Ibandronic acid (Bondranat), Pamidronate and Zoledronic acid.
We will keep you posted.