Development of acute nonlymphocytic leukaemia (ANLL) in myelomatosis

Acute promyelocytic leukaemia complicating multiple myeloma: evidence of different cell lineages

The association of leukemia and multiple myeloma is well described usually as a complication of chemotherapy but also in the absence of chemotherapy or at diagnosis. Such leukemias are typically acute myeloid leukemia (AML), particularly myelomonocytic subtype, and cases of acute promyelocytic leuke (APL) are rarely reported. Controversy exists as to whether myeloma and AML originate from a single haematopoietic progenitor or arise from different cell lineages. We report a case of a 58 year old female who developed APL 10 months following diagnosis of nonsecretory light chain (kappa) myeloma which had been treated with local spinal irradiation and low dose oral melphalan and prednisone. Clonality had originally been demonstrated by light chain restriction (kappa) of her bone marrow plasma cells whilst immunoglobulin heavy chain and T cell receptor genes were germ line. At development of APL cytogenetics revealed t(15;17) and PML-RAR fusion gene was detected by RT-PCR. The patient was treated with all-trans retinoic acid (ATRA) and received 2 cycles of consolidation chemotherapy with Idarubicin. Following this therapy the t(15;17) and PML-RAR were both undetectable whilst the clonal population of kappa staining plasma cells persisted. This particular patient represents a rare case of APL complicating multiple myeloma with persistence of the myeloma clone but disappearance of PML-RAR alpha RNA following therapy. This case study appears to support the argument that the APL and myeloma originated from distinct cell lineages.

Relapse of aggressive myeloma after complete remission in secondary acute leukemia: coincidence or consequence?

We describe a patient with multiple myeloma who developed secondary acute myelomonocytic leukemia after long-term melphalan treatment. Following two courses of low-dose cytarabine, complete remission of the A.M.L. was achieved. Shortly thereafter an aggressive relapse of the quiescent myeloma occurred with acute renal failure and massive infiltration of bone marrow with multinucleated giant plasma cells. Although it is well known that administration of melphalan to patients with multiple myeloma increases the likelihood of A.M.L., this case demonstrates that treatment of A.M.L. in a patient with multiple myeloma may perhaps influence the course of multiple myeloma.

Cytogenetic abnormalities in acute leukemia complicating melphalan-treated multiple myeloma

The cytogenetic findings in 11 patients with multiple myeloma in whom a myelodysplastic syndrome or an acute nonlymphocytic leukemia developed are reported. All patients were treated with oral melphalan for 2-9 years in a total dose of 0.5-4.1 g. When examined during the myelodysplastic or leukemic phase, all patients had an abnormal bone marrow karyotype, hypodiploid in nine of the 11 cases. The chromosome abnormalities were clearly nonrandom and comprised a 5q deletion in three cases, monosomy 5 in four cases, deletion 7q--in two cases, and monosomy 7 in three cases. Loss of material from the long arm of chromosomes 5, 7, or both was found in eight patients. The different chromosome abnormalities were not associated with any specific morphological or clinical features.

Acute myeloblastic leukaemia associated with solitary plasmacytoma of the ilium

A 72 year old man developed acute myeloblastic leukaemia two years after he had been treated with local curative therapy and chemotherapy for a solitary plasma cytoma of the ilium.