Does genetics impact how long patients respond to treatment for recurrent multiple myeloma?

This study evaluated whether certain genetic markers affect how long patients respond to treatment for recurrent multiple myeloma (MM). This study found that patients without these genetic markers had better outcomes compared to patients who did have them.

Multiple myeloma is a type of cancer of the bone marrow that can lead to abnormal immune cells. High-dose chemotherapy followed by a stem cell transplant (SCT) remains a key part of treatment for patients with MM. This involves collecting healthy stem cells from the patient. Then, the cells are reintroduced back into the patient.

SCT is effective for many patients with MM. However, for some patients, the cancer comes back (relapse). Previous studies have suggested that certain genetic markers associated with cancer can impact the outcome of therapy for MM. This is called cytogenetics. Whether these genetic markers affect treatment response for patients with MM remains unclear.

This study included 297 patients with recurrent MM. 50.2% of patients had genetic analysis done at the start of the study. Only 174 patients were included in the final analysis. Of these, 43 had SCT and 45 received weekly cyclophosphamide (Cytoxan). Patients were followed-up for an average of 76 months.

At follow-up, 92.0% of patients had tumor growth or spread. Fewer patients in the SCT group had tumor growth or spread compared to the cyclophosphamide group (86.5% vs. 95.3%).

Overall, patients survived for an average of 70 months. Patients who had SCT survived for an average of 12 months longer compared to the cyclophosphamide group (67 months vs. 55 months).

Patients who had SCT experienced tumor growth or spread 8 months later than patients treated with cyclophosphamide (19 months vs. 11 months).  SCT was significantly associated with a 60% lower risk of tumor growth or spread compared to cyclophosphamide.

Patients who had SCT survived for significantly longer than patients treated with cyclophosphamide (67 months vs. 55 months). SCT was significantly associated with a 36% lower mortality risk compared to cyclophosphamide.

This study found that patients without certain genetic markers had better treatment outcomes compared to patients who had these markers. The authors suggest that SCT may help improve survival for patients who have a second relapse.

This study was a retrospective study. This means that it analyzed data collected from a previous study. Therefore, these results may be impacted by the interpretation of the data by different investigators. More studies are needed to confirm these results.

Talk to your doctor if you have questions about the management of MM with certain genetic factors.