New treatment available to help when cancer has spread to the bones

When cancers spread to the bone, painful and debilitating complications often occur including severe pain, bone fracture and damage to the spine and even compression of the spinal cord.  Since last September, a new Novartis Oncology drug, Zometa is available to mitigate these problems.

Endocrine drugs are the standard treatment for patients with advanced prostate cancer.  Drugs such as Zoladex work to inhibit the action of testosterone, which otherwise would stimulate the growth of the cancer.  Radiotherapy can be useful for pain relief. So too can chemotherapy, pain killers and on occasion orthopaedic intervention.  But now there is Zometa as an addition to the armoury.

How does Zometa work?

Bone is alive.  Cells die and break down and new cells are laid down in the bone to replace them.  Once cancerous cells are present in bone, they cause abnormal dissolving or wearing away of the bone. In so far as new bone is formed, it is dense and poor quality and laid down not where cells have been removed but somewhere else, thereby deforming the bone structure.  These two actions of bone erosion and abnormal bone creation in the wrong place are the root cause of the nasty complications which occur in patients with cancer which has spread to the bones.

Zometa operates by binding to bone surfaces and working directly against the cells that cause bone breakdown.  It is important to understand that Zometa, as far as is known, is not treating the underlying cancer.  It is treating the bone to strengthen it and prevent complications.

How is Zometa given to the patient?

It is given via an intravenous drip for fifteen minutes or so every three weeks.  At least half the patients report an immediate reduction in pain so their quality of life rises from the first injection.  Receiving it is typically accompanied by the prescription of vitamin D and Calcium to maintain or increase bone density.

What can Zometa achieve?

Zometa has been shown to reduce the risk of bone complications by some 40% over a two year period.  It is licensed for prescribing in the UK but has not been assessed by the National Institute for Clinical Excellence (NICE) nor is it on their agenda until after 2005.  It costs some £120 per month.

The problems in getting Zometa prescribed include the fact that to some urologists it is not yet well known.  Cost may also be a problem.  There is also the practical problem that outpatient intravenous facilities are within oncology rather than urology departments.

Professor Robert Coleman of the Cancer Research Centre, Weston Park Hospital Sheffield is an authority on Zometa.  He suggests that patients on long term endocrine treatment should have their bone density monitored (since the treatment itself causes slow bone loss).  This too can cause an interdepartmental problem in hospitals because the x-ray machines which measure bone density are typically within rheumatology departments.

Details of the trials of Zometa can be found in the Journal of the National Cancer Institute Vol 94, no 19, October 2002.