The results of a recent study suggest that although the chromosomal abnormalities t(4;14) and del(17p) are associated with poor prognoses in newly diagnosed multiple myeloma patients, Velcade-dexamethasone therapy improved survival among patients with t(4;14) compared to treatment with vincristine, doxorubicin, and dexamethasone.

However, patients with the t(4;14) abnormality did not respond as well to Velcade and dexamethasone as patients without the abnormality.  Patients with del(17p) did not show the same improvements when treated with Velcade-dexamethasone.

The presence of chromosomal abnormalities in the plasma cells of multiple myeloma patients is associated with poor outcomes. Some novel drugs, such as Velcade (bortezomib), have been shown to overcome the poor prognosis associated with certain abnormalities, such as t(4;14), a translocation of a chromosomal region from chromosome 4 to chromosome 14, and del(17p), a deletion in a region of chromosome 17. However, these findings are based on a small number of patients.

To shed more light on the issue, French researchers investigated a large group of newly diagnosed multiple myeloma patients under the age of 65 years who received four cycles of Velcade and dexamethasone (Decadron) as their initial treatment, followed by high-dose melphalan (Alkeran) and stem cell transplantation.

Of the 507 patients included in the study, 106 were positive for the t(4;14) abnormality and 54 were positive for del(17p).

The researchers found that at a median follow-up of two years, more patients with t(4;14) (41 percent) relapsed than patients without this chromosomal abnormality (36 percent). In addition, patients without the chromosomal abnormality had a significantly higher 4-year overall survival rate than patients with the t(4;14) abnormality.

The researchers found similar results for patients with the chromosomal abnormality del(17p). The median event-free survival time was 14 months for patients with del(17p), compared to 36 months for patients without the chromosomal abnormality. The 4-year overall survival rate was 50 percent for patients with del(17p), compared to 79 percent for patients without del(17p).

In follow-up analyses, the researchers compared the results of their study with another set of 512 patients who received four cycles of vincristine, doxorubicin (Adriamycin), and dexamethasone (VAD) as initial therapy. Of this group, 98 were positive for t(4;14) and 119 were positive for del(17p).

They found that in comparison to VAD, Velcade-dexamethasone significantly improved outcomes for patients with t(4;14). Patients with this chromosomal abnormality who received Velcade-dexamethasone as initial therapy had a median event-free survival of 28 months and a 4-year overall survival rate of 63 percent, compared to 16 months and 32 percent for patients who were treated with VAD.

The researchers did not observe any difference between the two treatments with regard to outcomes for patients with del(17p).

The researchers concluded that based on their findings, Velcade-dexamethasone may become the standard of care as initial treatment for patients with the t(4;14) abnormality.

They added that a standard of care for patients with del(17p) has yet to be determined.

For more information about this study, please refer to the Journal of Clinical Oncology (abstract).