Avascular Necrosis of Bone after Therapy for Multiple Myeloma: A Study of 561 Consecutive Patients.

Purpose: To assess the prevalence, time of onset, risk factors, and outcome of avascular necrosis (AVN) of bone in patients with multiple myeloma undergoing antineoplastic therapy.

Patients And Methods: We reviewed the medical records of 561 myeloma patients (553 evaluable) enrolled in a treatment protocol consisting of dexamethasone-containing induction chemotherapy, autologous stem cell transplantation (ASCT), consolidation chemotherapy and maintenance with alfa-interferon. Patients were randomized at enrollment to receive thalidomide (269 pts) or no thalidomide (284 pts) throughout the study period.

Results: At a median follow-up of 33 months (range, 5–114 months), AVN of the femoral head (s) developed in 49 of 553 patients (9%). Median time to onset of AVN was 12 months (range, 2–41 months). Three risk factors for AVN were identified by multivariate analysis: cumulative dexamethasone dose (p=0.0006; O.R. 1.028; 95% C.I. 1.012–1.044 per 40 mg dexamethasone), male gender (p=0.009; O.R. 0.390; 95% C.I. 0.192–0.790) and younger age (p=0.0122; 95% O.R. 0.961, C.I. 0.934–0991/year). AVN-related pain and limited range of motion of the affected joint were present in only 9 and 4 patients, respectively. Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) failed to detect abnormal uptake in the AVN-affected bones. Thalidomide-treated patients had a prevalence of AVN similar to that of the control group (8 % vs.10%, respectively; p=0.58).

Conclusion: AVN is a rare and usually asymptomatic complication in myeloma patients undergoing antineoplastic treatment with dexamethasone-containing regimens and ASCT. Cumulative dexamethasone dose, male gender and younger age, but not thalidomide, increase the risk of AVN. FDG-PET does not contribute to the diagnosis of this complication