Canterbury DHB

Peripheral Blood Stem Cell Harvesting and Mobilisation Protocols

General Comments

Peripheral blood stem cells are usually obtained after mobilisation with cytokines alone or in combination with chemotherapy.

Factors adversely affecting stem cell reserve include:

• Extensive prior chemotherapy, including the number of cycles, duration of chemotherapy, the stem/progenitor cell toxicities of particular medications such as carmustine and fludarabine and the effects of certain diseases/therapies eg AML. It is also known that short intervals between repeated chemotherapy courses, usually facilitated by growth factors, severely impairs progenitor stem cell mobilisation.
• Previous irradiation to marrow stem cell containing compartments e.g., pelvis, spinal column.
• Other surrogate markers of impaired mobilisation potential include delayed haemopoietic recovery following previous cycles especially for platelets.
• Extensive tumour involvement of the marrow.
• Unknown factors where normal donors mobilise poorly after G-CSF administration.
• Age: > 55 years has been identified as a risk factor for poor mobilisation in normal donors.

In practice often a trial of stem cell harvesting is required and the timing of harvesting is dictated by the kinetics of WBC and CD34⁺ counts, the yields from previous harvests, and target CD34 numbers required.

Peripheral Blood Stem Cell Mobilisation Protocols

The following protocol is generally used for PBSC harvest. The choice of protocol will be made by the consultant supervising the transplant procedure.

• Cyclophosphamide/G-CSF PBSC mobilisation.

Note: G-CSF may be substituted with Pegylated G-CSF 6 mg single dose on day 3.

PBSC harvest can also be done during recovery after some chemotherapy schedules and these include:

• ICE - followed by G-CSF for PBSC mobilisation.
• IVE - followed by G-CSF for PBSC mobilisation.

Note: G-CSF is normally given after ICE and IVE in a dose of 5 mcg/kg. If stem cells are to be harvested a higher dose of G-CSF is given (10 mcg/kg).

Note: These 2 schedules can be combined with Rituximab if clinically appropriate.

Other novel agents such as Perixafor (AMD3100) may be considered in exceptional circumstances. However the cost of this agent generally precludes its use.

For current trials, see the Clinical Trials page on the Intranet.

Topic Code: 9010