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Biomedical subjects

L C Peterson

Publications and source records attributed to L C Peterson.

6 recordsLinked to original sources
PubMed1992

Frequent clonal abnormalities of chromosome band 13q14 in B-cell chronic lymphocytic leukemia: multiple clones, subclones, and nonclonal alterations in 82 midwestern patients.

We performed cytogenetic analyses of peripheral blood lymphocytes from 82 Midwestern B-cell chronic lymphocytic leukemia (B-CLL) patients. The cells were cultured with mitogens for 3-4 days. At least 15 metaphase cells were analyzed in 79 (96%) cases. Fifty (63%) of the 79 patients had clonal chromosomal alterations. Structural modifications of the long arm of chromosome 13 at or near band 13q14 were the most frequent abnormalities, identified in 23 (46%) of the patients with clonal abnormalities. In several patients, the abnormality involving band 13q14 was the sole chromosomal alteration. There was a high incidence of complex karyotypes. Nine patients had multiple subclones that appeared to result from clonal evolution; seven patients had cytogenetically unrelated clones; three patients had both subclones and cytogenetically unrelated clones. Nonclonal abnormalities were also prominent. Our study confirms the high incidence of clonal abnormalities involving chromosome arm 13q and documents the clustering of abnormalities at band 13q14 in B-CLL. The evidence for clonal evolution and the presence of multiple unrelated clones in these patients suggest that B-CLL may not be a karyotypically stable disease.

Aged↗
PubMed1977

The Philadelphia chromosome (Ph1) in adults presenting with acute leukaemia: a comparison of Ph1+ and Ph1-patients.

To evaluate the frequency and clinical significance of the Philadelphia chromosome (Ph1) in adult acute leukaemia, bone marrow chromosomes were studied in 15 adults with acute lymphocytic leukaemia (ALL) and 55 with acute nonlymphocytic leukaemia (ANLL). Morphology, clinical findings, therapeutic response and survival were compared in patients with and without the Ph1. The Ph1 was found in six newly diagnosed adults presenting with ALL. Adults with Ph1+ ALL differed from those with Ph1-ALL in being older, in having more frequent lymphadenopathy and splenomegaly and in demonstrating higher initial leucocyte counts and more peripheral blasts. Complete remissions were obtained in all nine adults with Ph1-All but in only three of six with Ph1+ ALL. Adults with Ph1-ALL survived significantly longer. Four adults with ANALL were Ph1+. They did not respond to treatment and survived significantly shorter periods than adults with Ph1-ANLL. No clinical or morphologic features indicated which patients with acute leukaemia would have the Ph1. Since the presence of the Ph1 in acute leukaemia has therapeutic and prognostic significance, marrow chromosome studies should be performed in adults presenting with acute leukaemia, especially ALL.

Adolescent↗
PubMed1976

Blast crisis as an initial or terminal manifestation of chronic myeloid leukemia. A study of 28 patients.

The clinical and morphologic features of nine patients who initially presented with blastic leukemia and the Philadelphia chromosome were studied. Corresponding features were evaluated at the time of diagnosis of blast crisis in 19 patients who had a previous history of chronic myeloid leukemia (CML). Although many of the presenting symptoms and signs were similar, infections, lymphadenopathy, tissue infiltration and central nervous system involvement were more common in patients who presented with blastic leukemia. Marked leukocytosis, basophilia and marrow hypercellularity were present in both groups. Although patients in both groups had morphologic patterns that resembled acute leukemia, cytology suggestive of acute lymphocytic leukemia was more frequent in patients who initially presented with blastic leukemia. Megakaryocyte, platelet and erythroid abnormalities were more frequent in patients with a prior history of CML. Although there were clinical and morphologic features in the patients who presented with blastic leukemia which suggested the diagnosis of CML in blast crisis, chromosome studies were necessary to identify some of these patients. In both groups of patients multiple therapeutic regimens were used. Complete remissions were obtained in two patients; both presented with blastic leukemia, had "lymphoblastic" morphology and were treated with chemotherapeutic agents generally used for the treatment of acute lymphocytic leukemia. It appears that morphology of the blast crisis may be important in choosing the treatment regimen.

Adult↗
PubMed1975

Morphology of chronic lymphocytic leukemia and its relationship to survival.

The morphology of lymphocytes in blood and bone marrow from patients with chronic lymphocytic leukemia was studied; blood lymphocyte morphology was related to survival. Three primary morphologic groups emerged. Group 1 was characterized by small to medium-sized lymphocytes with narrow rims of cytoplasm and coarsely clumped nuclear chromatin. In group II the predominant lymphocytes were large with abundant cytoplasm. Group III was characterized by a heterogeneous population of lymphocytes with characteristics of both groups I and II. Clinical features of the patients were studied, and B and T typing of the lymphocytes was done. The median survival in group I was 26+ months; in group II 46+ months; and in group III 50+ months. Our data are at variance with previous reports and suggest that survival in patients with large lymphocytes is longer than in those with small lymphocytes.

Aged↗