Osteonecrosis of the jaw in patients taking bisphosphonates

Bisphosphonate-associated osteonecrosis of the jaw: a review of 35 cases and an evaluation of its frequency in multiple myeloma patients

Over a period of 28 months, we observed five cases of osteonecrosis of the jaw (ONJ) in cancer patients treated with bisphosphonates (BP) at our institution. This prompted us to undertake a retrospective, multicenter study to analyse the characteristics of patients who exhibited ONJ and to define the frequency of ONJ in multiple myeloma (MM). We identified 35 cases in Gruppo Italiano Studio Linfomi centers during the period 2002 - 05. The median time from cancer diagnosis to the clinical onset of ONJ was 70 months. In these 35 cases of ONJ, 24 appeared 20 - 60 months after starting BP treatment. The time for the onset of ONJ was significantly shorter for patients treated with zoledronic acid alone than for those treated with pamidronate followed by zoledronic acid. The frequency of ONJ in the MM group during the study period was 1.9%, although the nature of the present study may have resulted in an underestimation of ONJ cases. Our analysis strongly suggested an association between the use of BP and the occurrence of ONJ, although we were unable to identify any definite risk factors with a retrospective study. The most frequently ONJ-associated clinical characteristics were chemotherapy treatment, steroid treatment, advanced age, female sex, anemia, parodonthopaties/dental procedures and thalidomide (in the case of MM patients).

[An historical case of malignant hyperparathyroidism with unusual metastatic sites]

We report a historical case of hyperparathyroidism in a young patient hospitalized for an array of osteolytic foci and incomplete fracture associated with a swollen neck, revealing a very special form of a metastatic parathyroid carcinoma with unusual multiple locations and exceptional medullary flooding. Carcinoma of the parathyroid gland produces a malignant hypersecreting tumor particularly difficult to diagnose. Treatment of this rare tumor is primarily surgical. The preoperative syndrome is unusually severe primary hyperparathyroidism. Intraoperatively, the size of the tumor and its local extension to surrounding tissue are highly suggestive. Confirmation requires pathological analysis of the operative specimens and can be further supported by the clinical course of local recurrence or metastasic spread. Specific immunohistochemical techniques have recently been shown to be contributive. The diagnosis is strengthened in the presence of associated Schantz and Castelman criteria. Foci of local extension can be identified preoperatively with ultrasound, (99m)Tc-sestamibi scintigraphy and MRI of the neck and mediastinum. The prognosis depends mainly on the possibility of achieving complete resection at the initial surgery. In some cases, very aggressive complementary postoperative radiotherapy is likely to improve locoregional control of the tumor. Chemotherapy alone or in combination with radiation has not demonstrated its effectiveness. The disease course and control can be monitored by regular assay of serum calcium and the parathormone.

[Humoral hypercalcemia revealing a malignant non hodgkin lymphoma]

INTRODUCTION

Hypercalcemia is a rare complication of non-Hodgkin lymphoma. Usually, hypercalcemia occurs late in the disease course, except for high-grade lymphoma. Most often hypercalcemia is related to excessive level of circulating PTH-rP or sometimes, 1,25(OH)2D3. Concomitant high plasmatic concentration of PTH-rP and 1,25(OH)2D3 is uncommon.

EXEGESIS

We report the case of a 82-year-old man who presented with abdominal pain and weight loss, leading to the diagnosis of diffuse large-B-cell lymphoma (high-grade lymphoma) associated with symptomatic hypercalcemia (3.21mmol/l). PTH-rP and 1,25(OH)2D3 plasmatic levels were high. Calcium concentration was normalized with glucocorticoids and sequential chemotherapy.

CONCLUSION

This case report confirms that hypercalcemia, as consequence of excessive plasmatic level of PTH-rP secreted by tumoral cells, can occur early in the course of high-grade lymphoma. Glucocorticoids and chemotherapy are the best treatment options.

Osteonecrosis of the jaw and bisphosphonates: a comparison with white phosphorus, radium, and osteopetrosis

INTRODUCTION

Recent reports of bisphosphonate-associated jaw osteonecrosis are reminiscent of earlier incidents in which a comparable syndrome was caused by occupational exposure to white phosphorus or radium. Osteonecrosis of the jaw is also caused by an inherited disease: osteopetrosis. This review analyzes the biomedical and social aspects of these four situations associated with jaw osteonecrosis.

RESULTS

Clinical evidence is contradictory but suggests aminobisphosphonates cause rare cases of jaw necrosis. In addition to jaw problems, generalized skeletal defects characterize osteopetrosis and exposure to phosphorus or radium and there is evidence of decreased bone resorption in these conditions and with bisphosphonate therapy.

CONCLUSION

Bisphosphonate-induced jaw necrosis appears to be an on-target toxicity as the same mechanism, inhibition bone resorption, probably underlies both the therapeutic and adverse effects. Since bisphosphonates are retained for long periods by bone the theoretical potential for skeletal toxicity is increased by using higher doses of potent aminobisphosphonates administered less frequently.

Bisphosphonate-related osteonecrosis of the jaws: an update on clinical, pathological and management aspects

Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is mainly observed in patients with multiple myeloma and bone metastasis from solid tumors receiving iv bisphosphonate therapy. The reported incidence of BRONJ is significantly higher with the iv preparations zoledronic acid and pamidronate while the risk appears to be minimal for patients receiving oral bisphosphonates. Currently available published incidence data for BRONJ are based on retrospective studies and estimates of cumulative incidence range from 0.8 to 12%. The mandible is more commonly affected than the maxilla (2:1 ratio), and 60-70% of cases are preceded by a dental surgical procedure. The signs and symptoms that may occur before the appearance of clinical evident osteonecrosis include changes in the health of periodontal tissues, non-healing mucosal ulcers, loose teeth and unexplained soft-tissue infection. Although the definitive role of bisphosphonates remains to be elucidated, the inhibition of physiologic bone remodeling and angiogenesis by these potent drugs impairs the regenerative capacity of the bone causing the development of BRONJ. Tooth extraction as a precipitating event is a common observation. The significant benefits that bisphosphonates offer to patients clearly surpass the risk of potential side effects; however, any patient for whom prolonged bisphosphonate therapy is indicated, should be provided with preventive dental care in order to minimize the risk of developing this severe condition. This article provides an update review of current knowledge about clinical, pathological and management aspects of BRONJ.

Osteonecrosis of the jaw related to the use of bisphosphonates

PURPOSE OF REVIEW

Osteonecrosis of the jaw associated with the use of potent nitrogen containing bisphosphonates is a new and challenging clinical entity with a high impact on quality of life. This review attempts to consolidate the rapidly expanding literature into practical guidelines and provides expert consensus for areas of uncertainty.

RECENT FINDINGS

Diagnostic criteria and a staging system for osteonecrosis of the jaw have been proposed, and histomorphologic analysis has confirmed osteonecrosis of the jaw as a proper disease, distinctively different from osteoradionecrosis. Various guidelines for the management of osteonecrosis of the jaw have been suggested and further retrospective research has provided new insights into its epidemiology.

SUMMARY

Osteonecrosis of the jaw is a distinct entity of uncertain origin that is increasingly being observed in patients treated with potent aminobisphosphonates, although the etiology is probably multifactorial. Recent data confirm the predisposition of multiple myeloma patients to develop osteonecrosis of the jaw. Although various treatment strategies have been reported, conservative management remains the mainstay of therapy.

Pathophysiology and natural history of avascular necrosis of bone

Avascular necrosis of bone (AVN) occurs as two main variants, local and systemic. Local AVN is usually caused by trauma or microtrauma; examples include primary osteonecrosis of the medial condyle, vertebral osteonecrosis, necrosis after meniscectomy, and osteonecrosis of the mandible or small bones. Systemic AVN manifests as epiphyseal necrosis or bone infarction, which is often multifocal. Little is known about the factors that trigger AVN. One possible mechanism is intraluminal obliteration of blood vessels by microscopic fat emboli, sickle cells, nitrogen bubbles (caisson disease), or focal clotting due to procoagulant abnormalities. Extraluminal obliteration may result from elevated marrow pressure or increased marrow fat. Cytotoxicity and genetic factors may be involved also. Many factors are probably capable of inducing AVN, and combinations of factors may be required, although the final mechanism is always critical ischemia. The natural history of AVN is better understood than the early triggering factors. AVN becomes detectable 1-6 months after exposure to an easily identifiable risk factor such as high-dose glucocorticoid therapy or femoral neck fracture. Later on, AVN is uncommon even when the patient remains exposed to the risk factor. The turning point in the natural history of AVN is subchondral plate fracture, which leads to collapse of the necrotic segment of the epiphysis, usually within the first 2 years. The risk of collapse depends chiefly on the initial size and location of the necrotic segment, which can be determined accurately by magnetic resonance imaging (MRI). This natural history has obvious clinical implications.