A new study published in JAMA Oncology has found that of all patients who have had cancer spread to their bones and started treatment, 2,8% have developed osteonecrosis within their jaw, also known as ONJ. This onset of osteonecrosis begins within 3 years of starting their cancer-fighting therapy.
This study was conducted by researchers at SWOG Cancer Research Network, which is funded by the NIH.
Practically any type of cancer can eventually spread to the bone. The treatment when this happens is Zoledronic Acid, which works to protect the bone.
Unfortunately, this therapy is associated with risk for developing ONJ.
ONJ causes bone within the jaw to be exposed. The wound doesn’t heal properly and leads to inflammation in the mouth. Patients experience pain, difficulty speaking, and issues eating.
ONJ can drastically impact the quality of life of cancer patients.
Approximately 280,000 adults in the United States have cancer in the bone, and we can assume that most are treated with Zoledronic Acid. According to the results displayed below, that would indicate that around 7,800 will develop ONJ within three years.
S0702 is the first study and the largest to determine the prevalence and risk factors of ONJ for cancer patients. It included 3,571 patients from 172 clinical trial sites. Of these, 3,491 were included in the final results.
All individuals in this study had cancer which had metastasized to the bone, and all were being treated with Zoledronic Acid (prescribed within the first 30 days of the study).
The majority of patients had the following kinds of cancer-
- Breast cancer
- Multiple Myeloma
- Lung Cancer
All of the patients in this trial had outcomes reported every 6 months. This data included dental, medical, and outcomes reported by the patient themselves. All of the patients were followed for a total of 3 years.
There were some individuals who were diagnosed with ONJ during the trial, and these individuals had dental exams every 3 months.
- 90 ONJ cases were documented
- Cumulative incidence of ONJ was 2.8%
- Highest ONJ rates at 3 years were in multiple myeloma patients
- Lowest ONJ rates at 3 years were in breast cancer patients
- Highest risk of ONJ was associated with poor dental health (dentures, past oral surgery, missing teeth, etc)
- ONJ was associated with smoking
- ONJ was associated with doses of Zoledronic Acid which were given in small intervals (5 weeks or less)
- ONJ was associated with a severely decreased quality of life due to pain and other oral symptoms
These findings are important because they provide insight into how we may decrease the incidence of ONJ. For instance, less frequent doses of Zoledronic Acid may minimize risk.
You can read more about this study here.