Treatment of Primary Plasma Cell Leukaemia in Subjects Under the Age of 70
Status:
Completed
Trial end date:
2016-09-01
Target enrollment:
Participant gender:
Summary
Plasma cell leukaemia is a rare variety of multiple myeloma with a poor prognosis. Plasma
cell leukaemia is defined as: at least 2,000 circulating plasma cells per µL for a blood
leukocyte count higher than 10,000/µL or 20% of plasma cells for a leukocyte count less than
10,000/µL. Plasma cell leukaemia can be either primary, when it constitutes the first
manifestation of the disease, or secondary in the setting of relapsed/refractory multiple
myeloma. Primary plasma cell leukaemia (PPL) is a rare disease, representing only 1 to 2% of
all cases of multiple myelomas at diagnosis. As the annual incidence of multiple myeloma in
France is about 4,000 new cases, an estimated 40 to 80 new cases of PPL would be observed
each year.
Few data are currently available in the literature concerning the pathophysiology and
therapeutic management of PPL, and are derived from retrospective series based small numbers
of patients. The prognosis of PPL in response to conventional chemotherapy remains poor with
a median survival of 7 to 14 months. However, longer survivals have been obtained with
intensive therapy and haematopoietic stem cell transplantation (allogeneic or autologous
HSCT).
The investigators propose to perform a prospective study of the management of patients with
PPL under the age of 70 years, in combination with a laboratory study: 12 weeks of induction
chemotherapy by liposomal Bortezomib-Dexamethasone-Doxorubicin (PAD) alternating with
Bortezomib-Dexamethasone-Cyclophosphamide (VCD) for a total of 4 cycles. Peripheral blood
stem cell collection after mobilization by G-CSF will be performed after high-dose
Cyclophosphamide chemotherapy. Autologous HSCT conditioned by high-dose Melphalan will be
performed during the following month for all responding patients. During the 3 months after
this first autologous HSCT, allogeneic HSCT with attenuated conditioning will be proposed in
patients under the age of 66 years in complete remission with a suitable donor, and another
systematic autologous HSCT will be proposed in all other patients. For all patients not
treated by allogeneic HSCT, consolidation/maintenance therapy will be performed 3 months
after the second autologous HSCT: 4 quarterly consolidations with
Bortezomib-Lenalidomide-Dexamethasone (VRD) with maintenance by 2 months of Lenalidomide
between these cycles, for a total duration of one year.
The laboratory assessment will consist of blood and bone marrow samples systematically
obtained at diagnosis for plasma cell phenotyping by cytometry, cytogenetics, FISH, study of
the gene expression profile and SNParray. A DNA bank and plasma bank will be constituted. The
investigators also propose to study residual disease by cytometry (after the first autologous
HSCT, before and at the end of the consolidation/maintenance phase), as it increasingly
appears to have a major impact on survival in multiple myeloma.