Total Skeletal Irradiation in Multiple Myeloma Before Second Autologous Hematopoietic Stem Cell Transplantation

Study Summary

The purpose of this study is to improve the efficacy of the HDC regimen by adding a novel, "targeted" means administering a variation of total body irradiation (TBI) radiation i.e., total skeletal irradiation (TSI) administered by helical tomotherapy (HT) before, and in addition to the current standard of HDC, at a dose of 200 mg/m2 (HDMel200). The underlying postulate of this endeavor is that TSI-HT will provide additional cytoreduction to HDMel alone, without producing additional (serious) toxicity. We will utilize a classical Phase I study design (i.e., dose escalation) in myeloma patients undergoing AHSCT2 to define a maximum tolerated dose (MTD) and dose limiting toxicity (DLT). Finally, although comparisons to other therapies are not typical (and/or feasible) for a Phase I study, we will compare, whenever possible, both the toxicity and the antimyeloma activity of the AHSCT2 to AHSCT1. This protocol will standardize, as much as possible the use of AHSCT2 both as a "tandem" and "salvage" procedure. Since sufficient AHSC (CD34+ cells) are routinely collected in adequate numbers for multiple AHSCTs, but recently used infrequently, it is important to work towards defining the optimal utilization of this resource.

Primary Outcome

MTD of high dose therapy consisting of escalating doses of Total Skeletal Irradiation administered via Helical Tomotherapy, followed by standard high dose chemotherapy of high dose Melphalan (200mg/m2) with amifostine cytoprotection before AHSCT.

Interventions

• RADIATION Total Skeletal Irradiation