Mixed-lineage leukemias and phenotypic shifts occurring in relapsed cases of acute T lymphoblastic lymphomas.
Specimens from 19 patients with NHL were also phenotyped at the onset of the disease; among them, 9 were studied in the relapse phase. The analysis was carried out with monoclonal antibodies directed against T and myeloid cells; at diagnosis, all cases presented an immature thymic phenotype. When analyzed at relapse, phenotypic changes were observed: intra-lineage dedifferentiations (6 cases); mixed-lineage lymphoid and myeloid (2 cases), and pure myeloid relapses (1 case). The molecular analysis of the TCR-genes configuration showed a germ-line pattern at onset and relapse in Case 9 and a modification of the rearrangement patterns during the evolution of the disease in Case 6. These data point out that the relapse is often accompanied by intra-lineage modifications resembling dedifferentiation and, more rarely by a myeloid switch. The phenotypic follow-up of these patients may be important to the implementation of chemotherapeutic protocols that are more adequate for the biological evolution of the disease.
Delia
D
D
Division of Experimental Oncology A, Istituto Nazionale Tumori, Milano, Italy.
Polli
N
N
Borrello
M G
MG
Fontanella
E
E
Biassoni
D
D
Morandi
F
F
Cattoretti
G
G
Orazi
A
A
Della Porta
G D
GD
D000911:Antibodies, Monoclonal; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000145:classification / Q000276:immunology / Q000473:pathology*; D015166:Monitoring, Immunologic; D010641:Phenotype; D011379:Prognosis; D013601:T-Lymphocytes / Q000276:immunology
D000911:Antibodies, Monoclonal