Early Relapse May Be Linked To Shorter Survival In Elderly Myeloma Patients
According to a recent Greek study, elderly myeloma patients who relapse early after receiving therapy with novel agents have a significantly shorter overall survival time compared to patients who remain in remission longer. In addition, results showed that a poorer quality of response to treatment with novel agents is associated with early relapse in these patients.“This study confirms other data that a [better quality of] response argues for a good outcome in patients with myeloma,” said Dr. Edward Libby from the University of New Mexico Cancer Center in Albuquerque who was not involved in the study.
However, Dr. Libby added that because the patients in the study were treated with different regimens, it is difficult to conclude why some patients did better and others did worse.
Based on their findings, the study authors recommended that elderly patients who experience an early relapse participate in clinical trials or receive additional treatment to try to improve their prognosis. They also encouraged efforts to identify patients who are at a higher risk for early relapse and to customize different treatment strategies for these patients.
Since their introduction, novel agents such as Revlimid (lenalidomide), thalidomide (Thalomid), and Velcade (bortezomib) have significantly improved treatment outcomes for elderly multiple myeloma patients compared to traditional chemotherapy.
Previous studies have shown that elderly myeloma patients treated with melphalan (Alkeran)-prednisone therapy, known as MP, along with either thalidomide or Velcade have a better quality of response compared to patients who receive MP without novel agents. All of these patients also have longer progression-free survival times, and some of them have longer overall survival times.
Another recent study has shown that the achievement of a complete response is a predictor of longer progression-free and overall survival in elderly myeloma patients who receive treatment with novel agents.
Improved treatment results with novel agents, however, have not always resulted in longer overall survival times in elderly patients.
For instance, results of a previous study indicate that thalidomide-interferon maintenance therapy following MP increases progression-free survival but not overall survival in elderly patients. Moreover, because thalidomide-interferon maintenance caused more side effects than interferon alone, the study authors stated that there was only a “limited benefit” for elderly patients to use thalidomide along with interferon as maintenance (see related Beacon news).
In order to shed light on whether quality of response is associated with progression-free survival and overall survival times in elderly patients treated with novel agents, Greek researchers analyzed medical data from 135 elderly myeloma patients treated at a medical institution in Athens.
All patients included in the study were over 65 years old. The majority of patients (84 percent) had advanced disease. All patients were ineligible for stem cell transplantation and received novel agent-based therapies. Fifty-five percent of patients received thalidomide-based regimens, 37 percent received Revlimid-based regimens, and 12 percent received Velcade-based regimens.
The researchers found that 28 percent of patients achieved a complete response, 23 percent achieved a very good partial response, and 30 percent achieved a partial response.
The researchers found that patients who achieved a complete response after initial therapy had a longer median progression-free survival time compared to patients who achieved a very good partial response or a partial response (31 months vs. 20 months and 23 months, respectively). The same was true for overall survival (62 months vs. 53 months and 38 months).
Furthermore, the authors found that poorer quality of response increased the likelihood of early relapse, which in turn decreased overall survival time.
Whereas 21 percent and 39 percent of patients who achieved a very good partial response and a partial response, respectively, relapsed early (defined as a relapse within 12 months of completing initial treatment), three percent of patients who achieved a complete response had an early relapse.
Patients who relapsed early also had a significantly shorter overall survival time than patients who did not relapse early (15.4 months vs. 53 months).
By statistical analysis of these results, the authors determined that patients who relapsed early had over a seven-fold increase in the risk of death.
“[These findings] may argue that using our best therapies upfront to achieve a complete response is the right thing to do,” said Dr. Libby. “In many circumstances, combining new therapies early [during treatment] gives the best response.”
Thirty-nine percent of patients received a second line of therapy after they relapsed or their disease progressed.
The study authors noted, however, that secondary therapies did not improve treatment outcomes for patients who relapsed early.
“The fact that [the patients] in this study had a poor performance status overall may have affected their response and their ability to tolerate subsequent therapy,” suggested Dr. Libby.
As a follow-up to the study, Dr. Libby recommended larger studies to investigate effective therapies for elderly myeloma patients.
“Most patients with myeloma are older patients, but most studies to date have been on younger patients,” he explained. “I think, overall, we need many more [larger] studies that focus on the elderly.”