Lymphoblastic transformation of Ph1-positive chronic myeloid leukaemia: therapeutic implications and relevance to haemopoietic stem cell theory

Busulphan versus combination chemotherapy for initial treatment of chronic granulocytic leukaemia

In a pilot study, 21 consecutive and previously untreated adults with chronic granulocytic leukaemia received either busulphan (group 1: n = 11) or a combination of the epipodophyllotoxin VP16-213 with cytosine arabinoside and doxorubicin (group 2: n = 10). Using a standardised protocol, objective response, defined as a granulocyte count consistently less than 10 X 10(9)/1 with no clinical evidence of the disease, was achieved in 45 and 40% of the patients, respectively, and median survivals were 89 and 107 weeks (p greater than 0.05). Although there was no difference in morbidity, the study was discontinued because the combination chemotherapy was more complex to administer, was associated with greater patient inconvenience, and offered no advantage over single-agent therapy in managing the stable phase of chronic granulocytic leukaemia.

Chronic granulocytic leukemia: correlation of blastic transformation type with karyotypic evolution

Over a 3-year period, 26 patients with Philadelphia chromosome-positive chronic granulocytic leukemia were studied cytogenetically in both the chronic and blastic transformation phases of the disease; a further three patients were studied only after blastic transformation. Sixteen were considered to have adequate evidence of the type of transformation and form the basis of the report, where chromosome changes have been correlated with the morphological type of blastic transformation. Seven patients developed a myeloblastic transformation, seven a lymphoblastic transformation, and two an erythroblastic transformation. All patients in the myeloid group acquired one or more of the nonrandom changes associated with CGL blastic transformation, viz. +8,i(17q), +19, +22q-. Patients in the lymphoblastic group acquired structural abnormalities, apparently random in nature and usually in a small percentage of cells. The two patients with erythroblastic transformation developed markedly hyperdiploid cells (greater than 50 chromosomes) with both numerical and structural abnormalities. Patients in the lymphoblastic group appeared to have a slightly better prognosis than the myeloid group, whilst the patients with erythroblastic transformation had a very poor prognosis.

2. Lymphocyte surface marker studies in lymphoma and leukemia

In the past decade, studies of the markers expressed on the surface of malignant lymphocytes from patients with lymphoma and leukemia have greatly expanded our knowledge and understanding of these disorders. In addition, the results obtained have allowed individual cases to be categorized to prognostic groups, thus influencing the choice of therapy. These studies should now be considered routine in the evaluation of patients with lymphoid leukemias and lymphomas.