Hemophagocytic syndrome associated with retinoic acid syndrome in acute promyelocytic leukemia

Transplantation in rare lymphoproliferative and histiocytic disorders

BACKGROUND

Some uncommon lymphoproliferative and histiocytic disorders may present with an aggressive course and require hematopoietic stem cell transplantation (HSCT) as part of the therapeutic approach.

METHODS

Published research on the use of HSCT for the treatment of these disorders was reviewed and summarized.

RESULTS

Allogeneic HSCT may be indicated in patients with blastic plasmacytoid dendritic cell neoplasia, familial or secondary recurrent hemophagocytic lymphohistiocytosis, and resistant Langerhans cell histiocytosis. Autologous HSCT may be considered in patients with Castleman disease resistant to treatment. No role has been established for the use of HSCT for dendritic cell sarcoma.

CONCLUSIONS

HSCT has an evolving role in the treatment of select aggressive lymphoproliferative and histiocytic disorders.

ATRA Induced Reactive Hemophagocytosis: a Case Report

All trans-retinoic acid (ATRA) is a targeted therapy, used in Acute Promyelcytic leukemia (APL) and causes the abnormal promyelocytes to differentiate in to mature leucocytes, however their clearance in vivo is not known. ATRA has been found to be associated with hemophagocytosis, but sometimes one may find phagocytosis of differentiated cells by histiocytes without the overt manifestations of hemophagocytic syndrome. We report a case of APL showing differentiated cells being phagocytosed by marrow histiocytes while patient was getting ATRA therapy.

Hemophagocytic lymphohistiocytosis with MUNC13-4 gene mutation or reduced natural killer cell function prior to onset of childhood leukemia

Hemophagocytic lymphohistiocytosis (HLH) is a rare histiocytic reactive process due to mutations in the perforin, MUNC13-4 or syntaxin 11 genes, or secondary to malignancy, infection or autoimmune disorder. HLH as a preceding diagnosis to leukemia is rare. We report two cases with progression to acute leukemia, one heterozygous for MUNC13-4 and the other with reduced natural killer (NK) cell function and perforin expression. These defects may predispose to a secondary HLH-like presentation of pre-clinical leukemia or confer increased susceptibility to malignancy. HLH patients with genetic mutations or NK cell function abnormalities need monitoring for future malignancy even if the HLH resolves.

Therapy-related pure erythroid leukemia with hepatic infiltration and hemophagocytic syndrome

Pure erythroid leukemia (PEL) is an extremely rare disorder characterized by neoplastic proliferation of immature erythroblasts. A 66-year-old man, who had received chemoradiotherapy for hypopharyngeal cancer, was admitted because of pancytopenia. Bone marrow was infiltrated with 81% proerythroblasts positive for CD71 and CD235a. An increased number of macrophages with active hemophagocytosis was also present. Chromosome analysis showed hypodiploid complex abnormalities. The patient died of progressive disease despite induction chemotherapy. Erythroblastic infiltration into the liver and hemophagocytosis in the spleen were found at autopsy. Therapy-related PEL with hemophagocytic syndrome and hepatic infiltration of PEL has never been reported.

Retinoic acid syndrome: a review

The retinoic acid syndrome (RAS) is an unpredictable but frequent complication which may develop after administration of all-trans retinoic acid (ATRA) most commonly in patients with acute promyelocytic leukaemia (APL). In this review, we describe the incidence, predictive factors, clinical course, outcome and treatment of RAS in patients with APL treated with ATRA. The incidence of RAS in patients receiving ATRA is about 14-16%, with an associated mortality of about 2%. Initial high white blood cell (WBC) count, rapidly increasing WBC count and/or the presence of the CD 13 expression on leukaemic cells may help in identifying patients likely to develop RAS. Concurrent chemotherapy will probably decrease the risk of developing RAS but often exacerbates bleeding, leading to leucocytosis, thrombocytopenia, disseminated intravascular coagulation and fibrinolysis. Prophylactic steroids are not recommended but prompt administration of steroids at the first sign of unexplained dyspnea, fever, weight gain or pulmonary infiltrate, is critical. Liposomal ATRA is being investigated to induce haematological cure in APL without chemotherapy and to reduce the incidence of RAS but further validation of its usefulness is necessary.

Hemophagocytic syndrome preceding acute myeloid leukemia with der t [7:17][q12; q11], monosomy, 17 and 5p-

Hemophagocytic syndrome (HS) is a severe and acute proliferative process of histiocytes, often associated with infection or malignancy. No consistent clonal abnormality has been reported in HS. We report a case of a child presented with HS, who progressed later to acute myeloid leukemia (AML)-M4, associated with a clonal evolution, from normal to a complex karyotype consisting of t [7:17] and deletions in chromosomes 7, 17, and 5. This is the second report of involvement of 7q rearrangement in a child with HS that has progressed to AML. Additional studies are required to establish the association reported here, between HS with progression to AML and chromosome rearrangements that involve chromosome 7q.