Purpose: To evaluate the changes of bone marrow lesions on pelvic and spinal MR in patients with multiple myeloma after high-dose chemotherapy and autologous peripheral blood stem cell transplant.
Patients and methods: Pelvic and spinal MR examinations were obtained at presentation (myeloma diagnosis) and 1 year after transplant in 20 patients that were part of a group of 39 patients enrolled in a prospective study. The type of marrow replacement (classified in stages with stage 0: normal; stage 1: salt and pepper; stage 2: focal infiltration; stage 3: diffuse infiltration), the number and size of marrow lesions and the number of vertebral compression fractures were recorded. We have compared the findings prior to and following transplant, with correlation to the response to treatment and the use of biphosphonates.
Results: The type of marrow replacement was improved following transplant in 65% of patients (not statistically significant). The number and size of nodules > 20 mm showed significant reduction (p = 0.0224 and p = 0.0237 respectively). Lesions on MR improved in 50% of patients with good response and 75% of patients with poor response to treatment. Patients receiving biphosphonates showed more vertebral compression fractures.
Conclusion: The evolution of marrow replacing lesions on MR is discordant compared to the biological and clinical response to treatment. Pelvic and spinal MR evaluation at the time of diagnosis does not appear to be a good predictive factor of response to treatment. Biphosphonates do not appear to prevent new vertebral compression fractures. Pelvic and spinal MR provides interesting data in the follow-up of patients with myeloma following autologous transplant, especially in the local evolution of marrow replacing lesions, but our results do not justify its use in routine clinical practice.