BACKGROUND: Patients with untreated B-cell chronic lymphocytic leukemia have a high rate of complete remission when given the halogenated nucleoside analogue fludarabine. However, patients in whom the disease has proved refractory to primary treatment have a reduced life expectancy and a dismal outcome. METHODS: We treated four consecutive patients who had unsatisfactory responses to second-line or subsequent treatment with fludarabine with another halogenated nucleoside analogue, 2-chlorodeoxyadenosine. RESULTS: One patient with progressing lymphocytosis, anemia, and thrombocytopenia despite 10 courses of fludarabine entered a complete remission when treated with 2-chlorodeoxyadenosine. Two patients who had less-than-partial remissions after six courses of fludarabine had good partial remissions when treated with 2-chlorodeoxyadenosine. One patient with Coombs-positive hemolytic anemia who had no response to three courses of fludarabine had a partial remission, with resolution of hypogammaglobulinemia, when treated with 2-chlorodeoxyadenosine. CONCLUSIONS: There was no evidence of cross-resistance between fludarabine and 2-chlorodeoxyadenosine despite their similar structures. 2-Chlorodeoxyadenosine may induce a complete remission in chronic lymphocytic leukemia that is highly resistant to chemotherapy, and it deserves wider clinical evaluation in patients with this condition.
BACKGROUND:Patients with untreated B-cell chronic lymphocytic leukemia have a high rate of complete remission when given the halogenated nucleoside analogue fludarabine. However, patients in whom the disease has proved refractory to primary treatment have a reduced life expectancy and a dismal outcome. METHODS: We treated four consecutive patients who had unsatisfactory responses to second-line or subsequent treatment with fludarabine with another halogenated nucleoside analogue, 2-chlorodeoxyadenosine. RESULTS: One patient with progressing lymphocytosis, anemia, and thrombocytopenia despite 10 courses of fludarabine entered a complete remission when treated with 2-chlorodeoxyadenosine. Two patients who had less-than-partial remissions after six courses of fludarabine had good partial remissions when treated with 2-chlorodeoxyadenosine. One patient with Coombs-positive hemolytic anemia who had no response to three courses of fludarabine had a partial remission, with resolution of hypogammaglobulinemia, when treated with 2-chlorodeoxyadenosine. CONCLUSIONS: There was no evidence of cross-resistance between fludarabine and 2-chlorodeoxyadenosine despite their similar structures. 2-Chlorodeoxyadenosine may induce a complete remission in chronic lymphocytic leukemia that is highly resistant to chemotherapy, and it deserves wider clinical evaluation in patients with this condition.
Authors: G R Weiss; J G Kuhn; J Rizzo; L S Smith; G I Rodriguez; J R Eckardt; H A Burris; S Fields; K VanDenBerg; D D von Hoff Journal: Cancer Chemother Pharmacol Date: 1995 Impact factor: 3.333