How can Cusick risk of osteonecrosis of the jaw be managed in cancer patients receiving intravenous bisphosphonates?

Managing Osteonecrosis of the Jaw Risk in Cancer Patients on IV Bisphosphonates

All cancer patients should undergo comprehensive dental evaluation with completion of necessary invasive dental procedures before initiating IV bisphosphonate therapy whenever feasible, as this eliminates ONJ risk entirely. 1

Pre-Treatment Prevention Protocol

Mandatory Dental Assessment

• Complete hard and soft tissue dental evaluation with radiographic examination before starting IV bisphosphonates 1
• Treat all active oral infections and eliminate high-risk dental sites prior to bisphosphonate initiation 2
• Perform any pending tooth extractions, periodontal procedures, or other invasive dental work before treatment begins 1, 3
• Allow adequate time for complete osseous healing after dental procedures before initiating bisphosphonates 1

Laboratory Monitoring Requirements

• Measure serum calcium before starting treatment 1
• Assess renal function (serum creatinine) prior to each IV bisphosphonate dose 1, 3
• Monitor serum calcium and creatinine throughout the treatment period 1
• Correct vitamin D deficiency before initiating therapy to prevent hypocalcemia 2, 4

Supplementation Protocol

• Prescribe calcium 1200-1500 mg daily and vitamin D 400-800 IU daily unless contraindicated 1
• Ensure adequate calcium (800-1000 mg/day) and vitamin D (800 IU/day) intake throughout treatment 2

Risk Stratification

Magnitude of ONJ Risk

• IV bisphosphonates for cancer carry 6.7-11% ONJ incidence in multiple myeloma patients, dramatically higher than the <1 per 100,000 person-years seen with oral bisphosphonates for osteoporosis 2, 5
• Breast cancer patients on IV bisphosphonates have 1.2% ONJ incidence, while multiple myeloma patients have 2.4% incidence 6
• Risk increases with cumulative dose, frequency, and duration of bisphosphonate administration 1, 6

Primary Risk Factors

• Dental extractions during bisphosphonate therapy represent the single most consistent risk factor, with at least 60% of ONJ cases occurring after dentoalveolar surgery 2, 5, 7
• Tooth extraction during zoledronic acid treatment increases ONJ risk 53-fold in breast cancer patients and 10-fold in multiple myeloma patients 6, 8
• Use of poorly fitting dentures increases ONJ risk 5-fold 8
• Concurrent chemotherapy or corticosteroid use amplifies risk 1, 3
• Poor oral hygiene with periodontal disease and dental abscess 1

During Treatment Management

Patient Education and Monitoring

• Inform patients of ONJ risk, particularly with tooth extractions and invasive dental procedures 1
• Instruct patients to inform their dental practitioner of bisphosphonate treatment 1
• Maintain excellent oral hygiene with dental check-ups every 6 months once therapy has commenced 2
• Avoid elective invasive dental procedures during active bisphosphonate therapy whenever possible 2, 3

When Dental Procedures Are Necessary During Treatment

The evidence regarding bisphosphonate discontinuation before dental surgery remains controversial and equivocal 1, 2:

Two competing perspectives exist:

• Some experts hypothesize stopping bisphosphonates 2 months prior to oral surgery may allow better bone healing, with resumption delayed until adequate healing occurs 1, 2
• The alternative view holds that short breaks have no protective effect since bone effects of bisphosphonates persist for years after stopping 1, 2

Given this equipoise, the evidence-based surgical protocol when extraction is unavoidable includes:

• Administer prophylactic antibiotics perioperatively 2, 9
• Use atraumatic extraction technique with primary closure 2
• Defer resumption of bisphosphonates until the dentist confirms complete mucosal healing 2, 4
• Schedule follow-up every 6-8 weeks until complete healing 2

Critical Caveat for Cancer Patients

For patients with active cancer and bone metastases, interrupting IV bisphosphonate therapy poses tangible risks of pathologic fractures and spinal cord compression 2. The decision to interrupt therapy must weigh ONJ risk against skeletal-related event risk and should involve consultation with the treating oncologist 2, 9.

Management of Established ONJ

Referral and Treatment Approach

• Refer patients with suspected ONJ to a dental practitioner or oral surgeon with expertise in treating this condition 1, 2
• Consult guidelines from the International Task Force on Osteonecrosis of the Jaw, American Association of Oral and Maxillofacial Surgeons, and American Dental Association 1

Conservative Management Strategy

• A conservative, nonsurgical approach is strongly recommended over aggressive surgical measures 9, 7
• Systemic antibiotics for infection management 10, 9, 7
• Antiseptic oral rinses 10, 9, 7
• Pain control 10, 9, 7
• Limited conservative débridement of necrotic bone only 10, 9, 7
• Consider withdrawal of bisphosphonates 7

Prognosis

• ONJ is an uncommon but long-lasting disorder 6
• Lesions resolved in 23% of patients with conservative therapy in one series 6
• Dental surgery may exacerbate the condition in patients with established ONJ 3

Common Pitfalls to Avoid

• Do not confuse the low ONJ risk in osteoporosis patients (<1 per 100,000 person-years) with the dramatically higher 6.7-11% risk in cancer patients receiving monthly high-dose IV bisphosphonates 2, 5
• Do not perform dental extractions without antibiotic prophylaxis, as infection is a key risk factor 2
• Do not delay dental evaluation until after bisphosphonates have been started—early referral by oncologists for dental assessment is essential 8
• Do not assume young patients (age ≤40 years) on ovarian suppression have truly postmenopausal estrogen levels when considering adjuvant bisphosphonates 1