Essential Thrombocythemia With Transition Into Acute Leukemia

Abstract

A 57-year-old black man with sustained platelet count of 2 million/mm3 and evidence of intermittent gastrointestinal bleeding was diagnosed as having essential thrombocythemia. Studies of bone marrow morphology, platelet aggregation, and other variables were confirmatory of the disease. The patient was treated briefly with low doses of Myleran for less than three weeks. He was then lost to follow-up study. Approximately 16 months later he reappeared complaining of recurrent nose bleeds. He was found to be pancytopenic and diagnosis of acute leukemia was made on the basis of bone marrow aspiration.

Malignant squamous cell carcinoma arising in a lumbar dermoid cyst

“…Many cases of insidious malignant transformation of chronic myeloproliferative disorders have been described [9,10,11], but we found no evidence for this in our case. The serum SCC was high when first tested.…”

Megakaryoblastic Transformation of Primary Thrombocythemia

“…The role of chemotherapy in the genesis of leukemia could be dis cussed in 11 patients, who were previously treated by alkylating agents (4 patients) [2,7,10], radioactive phosphorus (6 cases) [4][5][6][7]11] or total body irradia tion (1 case) [3]. Three patients were treated by busulfan [8,11]. Only 1 patient presented a 'spontaneous' transformation of PT [9].…”

“…In some rare patients, the leukemic cells had monoblastic or myelomonocytic differentiation (3 cases) [2,10,11] while a myeloblastic transformation was identified in 9 other patients [3,4,[6][7][8][9]11]. How ever, in 2 of these latter patients a megakaryoblastic differentiation was demonstrated in a minority of peripheral blood cells which reacted with a mono clonal antibody specific for megakaryocyte-platelet glycoproteins Ilb-IIIa [11], In our patient, the mega karyoblastic origin of blood and bone marrow blast cells was demonstrated by the PPO reaction.…”

Essential Thrombocythemia Terminating in Acute Leukemia with Minimal Myeloid Differentiation -A Brief Review of Recent Literature

“…Besides Ph', the numerical and structural abnormalities of chromosome 21, such as a dele tion of the long arm of chromosome 21 (21 q~), are reported to be a marker for the development of acute transforma tion in ET [16], Second, cytotoxic agents and 32P possess mutagenic potentials, and may be a cause of acute leuke mia in transformed ET [7]. Although there are 5 reported patients without treatment other than our present case during the chronic phase of their disease [9,10,21,22], 4 of them were actually given either myelosupprcssive drugs or radioactive agents for a short time as our patient (table 2). Finally, bone marrow cells from patients with ET arc known to form few granulocyte-macrophage colony-form ing units (CFU-GM) or granulocyte colony-forming units (CFU-G) in culture.…”