more on osteonecrosis of the jaw (ONJ) and bisphosphanates

[Lani]

1: Swiss Med Wkly. 2006 Aug 5;136(31-32):504-9. Links
Clinical experiences with bisphopsphonate induced osteochemonecrosis of the jaws.

Dannemann C,
Zwahlen R,
Gratz K.
Department of Cranio-Maxillofacial Surgery, University Hospital of Zuirch, Zurich, Switzerland. christine.dannemann@usz.ch.
QUESTION: Bisphosphonates are frequently used drugs in the adjuvant therapy of bone metastases and tumour-induced hypercalcaemia, but also for osteoporosis or Pagets disease. Several publications within the last three years considered osteonecrosis of the jaws to be connected with bisphosphonate therapy. Until today possible treatment strategies contain antibiotics, hyperbaric therapy and operative treatment. The tendency of healing however seems to be extremely poor. All clinicians should be aware of this new kind of side effect of bisphosphonate therapy. METHODS: 14 patients with this new kind of osteonecrosis were admitted to the department of Cranio-Maxillofacial Surgery of the University Hospital of Zurich. 8 men and 6 women all received bisphosphonates for cancer therapy. A complete analysis of patients' data was performed. RESULTS: Of 14 patients in 7 the underlying disease disease was multiple myeloma. In one patient it was prostate cancer and in all female patients it was breast cancer. All of them had prior dental treatment and showed inflammatory signs and bacterial colonisation with localisation in the upper or lower jaw or in both. CONCLUSION: The infectious part of the bisphosphonate-induced osteonecrosis (ONJ) is considered to be more important than thought before. We presume that antimicrobial treatment is of utmost importance in the treatment of this kind of osteonecrosis. Patients with current or previous bisphosphonate therapy should be treated multidisciplinary to assure ideal prevention and treatment.
PMID: 16947089 [PubMed - in process]

[heblaj01]

The Swiss study posted by Lani seems to confirm previous medical/dental observations that:

1. osteonecrosis of the jaw (ONJ) while rare is a serious side effect
of bisphosphonates (bone damage & infections). See note below.
2. ONJ is much more common among those having dental procedures
3. ONJ is more frequent among multiple myolema patients perhaps due to the
fact that this cancer on its own causes bone damage or because of
adverse interaction between specific anticancer drugs & bisphosphonates .
4. ONJ occurs more frequently in patients who are administered Zometa after
Pamidronate which applies also to the higher frequency of other minor
side effects.


http://patient.cancerconsultants.com/myeloma_cancer_news.aspx?id=36348
Study Describes Osteonecrosis of the Jaw in Patients with Multiple Myeloma

http://www.us.zometa.com/info/cancer_bones/myeloma.jsp (http://www.us.zometa.com/info/cancer_bones/myeloma.jsp)
What You Should Know about Multiple Myeloma.
Myeloma Cells Can Cause Bone Damage

http://www.ada.org/prof/resources/topics/osteonecrosis.asp (http://www.ada.org/prof/resources/topics/osteonecrosis.asp)
American Dental Association
Osteonecrosis of the Jaw


Note:
Most papers dealing with frequency of ONJ due to Zometa call for a 1 to 2% rate of occurence. However a more recent report indicates a 10% rate (& 4% for Pamidronate) & "The mean time for osteonecrosis was 18 months following Zometa and 6 years following Aredia. They also reported that 81% of the patients with osteonecrosis had dental problems compared to 33% in those without osteonecrosis" :
http://professional.cancerconsultants.com/oncology_main_news.aspx?id=37833 (http://professional.cancerconsultants.com/oncology_main_news.aspx?id=37833)

Prevention and Management of Bisphosphonate Toxicities Reviewed


However, in the balance with this adverse effect are the potential benefits of Zometa in slowing disease in metastatic bone cancer from breast:
http://professional.cancerconsultants.com/news.aspx?id=37172
Zometa® Reduces Cancer Progression Over Clondronate®

Considering the fact that studies in Finland found Clodronate is also helpfull in preventing visceral metastases , the superiority of Zometa may be even more valuable