Faculty Bibliography

Allogeneic Haematopoietic Stem Cell Transplant (allo-HSCT) remains the only curative approach for Myelofibrosis (MF). Scarce information exists in the literature on the outcome and, indeed, management of those MF patients who relapse following transplant. We hereby report on the management and outcome of 202 patients who relapsed post allo-HSCT for MF.

The introduction of novel agents in the management of multiple myeloma and related plasma cell dyscrasias has changed our treatment approaches and subsequently the outcome of patients. Due to current advances, the European Myeloma Network updated the diagnostic and therapeutic recommendations for patients with Waldenström's macroglobulinemia (WM), AL-amyloidosis, monoclonal immunoglobulin deposition disease (MIDD), POEMS syndrome, and primary plasma cell leukemia. For patients with WM, the combination of rituximab with chemotherapy remains the treatment cornerstone, while the Bruton-tyrosine kinase inhibitor ibrutinib has been introduced and approved for relapsed/refractory disease. The management of light chain amyloidosis depends on the presence and severity of heart disfunction. If present, intensification with an autologous stem cell transplantation (ASCT) is not recommended. Further aggregation of misfolded light chains could be prevented by doxycycline or monoclonal antibodies targeting amyloid deposits. Initial treatment generally consists of melphalan/dexamethasone or bortezomib-based regimens. For relapsing patients, one can consider proteasome inhibitors, immunomodulatory agents, melphalan or daratumumab. Because intact or light-chain immunoglobulins are also the culprits for MIDD, the small monoclonal plasma cells' clones should be treated and generally respond well to bortezomib-based treatment. POEMS syndrome is a well-defined clinical entity that can present as solitary bone lesions or disseminated disease. Radiation therapy is used for patients with localized disease and result in long-lasting response. Systemic treatment should be proposed to patients with disseminated disease, but regimens that can worsen a pre-existing polyneuropathy should be avoided. PPCL is located at the other end of the spectrum of plasma cell disorders and is associated with an aggressive disease course and poor prognosis. It requires an imminent, multi-phase and novel agents-based therapy, including induction, ASCT, consolidation and maintenance, with short treatment-free intervals. Patients not eligible for transplant procedures require personalized, intensive therapeutic approach. Allogeneic stem cell transplantation can be used in selected patients.

Assessment of minimal residual disease (MRD) is being routinely used to assess response in patients with acute myeloid leukaemia (AML). While it is well established that pre-transplant positive MRD studies predict for relapse in patients transplanted either from matched sibling donors or matched unrelated donors, it is currently unknown whether MRD has comparable prognostic value in haploidentical stem cell transplantation (haplo-SCT). To this end we performed a retrospective analysis using the Acute Leukaemia Working Party/European Society of Blood and Marrow Transplantation multicentre registry. All adult AML patients with known MRD status at transplant who underwent a first T-cell replete haplo-SCT while in remission between 2006 and 2016 were included. Two hundred and sixty-five MRD-negative and 128 MRD-positive patients were assessed. In multivariate analysis, MRD-negative patients experienced lower relapse incidence and better leukaemia-free survival (LFS) compared to MRD-positive patients. Subset analysis for MRD-positive patients revealed that patients with donors positive for cytomegalovirus experienced decreased relapse rates as well as increased survival. A 6-month landmark analysis suggests that the clinical benefit of pre-transplant MRD negativity in terms of relapse, overall survival and LFS is realized at this time point. Pre-transplant MRD status is potentially a pivotal prognosticator of outcome in AML patients undergoing T-cell replete haplo-SCT.