Indian researchers recently identified several factors linked to improved survival among multiple myeloma patients who have undergone stem cell transplantation.

These factors included albumin levels at diagnosis and the achievement of a response – particularly a complete response – after transplantation.

Patients who achieved a complete response after transplantation, for example, had a median overall survival of 17 years.

The use of novel agents as initial treatment was also associated with improved overall survival.

Based on their findings, the study investigators recommend using initial therapy prior to transplantation that aims to achieve the highest response rate possible.  This approach, they argue, could increase the rate of complete responses post transplantation, thereby lengthening patient survival.

According to the study authors, future research into stem cell transplantation should focus on the timing of the transplant and the identification of patients who are at a higher risk for relapse.

High-dose chemotherapy followed by autologous stem cell transplantation (i.e., transplantation using a patient’s own stem cells) is a common treatment option for multiple myeloma patients age 65 years and under.

Prior studies have shown that patients who achieve a complete response after stem cell transplantation experience improved overall survival (see related Beacon ^[1] news).

The purpose of the current study was to confirm and identify additional factors that may predict survival outcomes in patients receiving an autologous stem cell transplant.

Study investigators retrospectively evaluated records from 170 multiple myeloma patients who had received a stem cell transplant at their cancer center between 1990 and 2010.

The median patient age was 52 years; 39 percent had received novel agents, such as thalidomide ^[2] (Thalomid), Velcade ^[3] (bortezomib), or Revlimid ^[4] (lenalidomide), as their initial therapy.

Of the 170 patients included in the analysis, 78 percent had responded to their initial treatment.

Patients received the transplant within a median of 10 months of their diagnosis.

The majority of patients received high-dose chemotherapy with 200 mg/m² of melphalan ^[5] (Alkeran) as part of their transplant. Lower dosages of melphalan (120 mg/m² to 150 mg/m²) were administered to patients with impaired kidney function.

Patients started producing blood cells a median of 11 days after the transplant.

Overall, 91 percent of patients responded to the transplant; 45 percent of patients achieved a complete response, 25 percent a very good partial response, and 21 percent a partial response. According to the study investigators, these results are similar to those of other recent studies.

The investigators found that a patient’s pre-transplant disease status, response to initial treatment, and time from diagnosis to transplant were factors that significantly affected their response to the transplant.

After a median follow-up time of 7 years, the median event-free survival was 3.4 years, and the median overall survival was 7.1 years.

The investigators found that albumin levels above 3.4 g/dL at diagnosis and the achievement of a response, in particular a complete response, after transplant were significant predictors of improved progression-free and overall survival.

Albumin is the most abundant protein in human blood plasma. A patient's albumin level is one of the factors used in the International Staging System to determine disease stage.

Patients with albumin levels greater than 3.4 g/dL, for example, had a median overall survival of  11.7 years versus 6.6 years for those with albumin levels equal to or less than 3.4 g/dL.  Patients who achieved a complete response after transplantation had a median overall survival of  17 years versus about 3.8 years for those who did not.

In addition, the use of novel agents as initial treatment was associated with improved overall and event-free survival survival.

Median event-free survival was 4.2 years among patients treated initially with novel agents.  It was 2.3 years among patients treated initially with the combination therapy known as VAD -- vincristine ^[6], doxorubicin ^[7] (Adriamycin), and dexamethasone ^[8] (Decadron). It was only 1.3 years among patients treated initially with regimens including either melphalan or cyclophosphamide ^[9] (Cytoxan).

The median overall survival has not yet been reached for patients in the study who received novel agents as initial therapy;  it was 7.1 years for patients initially treated with the VAD regimen, and 2.7 years for those initially treated with regimens including either melphalan or cyclophosphamide.

For more information, please see the study in Clinical Lymphoma, Myeloma & Leukemia ^[10] (abstract).