Recurrent childhood lymphocytic leukemia following cessation of therapy.Treatment and response

Abstract

A unique population of patients--children who developed recurrent acute lymphocytic leukemia (ALL) following cessation of initial prolonged therapy--was studied. During a 2-year period, 17 such children were admitted to a planned combination chemotherapy program. Complete bone-marrow remissions were achieved in 16 patients, and the median duration of second hematologic remissions was 216 days. These responses were significantly better than those obtained in seven patients who relapsed during the administration of continuation chemotherapy. Although the rate and duration of induced remissions were notably high, 9 of the 17 patients who relapsed off therapy have again developed recurrent leukemia. This result, together with the moderate toxicity encountered during treatment, indicates that more therapy is needed. The equal proportion of bone marrow and meningeal relapses was interpreted to mean that a secon course of preventive central nervous system therapy early in remission may be especially useful.

Favorable response to maintenance therapy of second or subsequent remissions in childhood acute lymphocytic leukemia

“…'* Specific CNS treatment was not administered in either of the above series. Rivera et al presented evidence that CNS relapse is a frequent 22 Rivera et a1. 20 Lane et al l3 finding in children in second marrow remission and that IT chemotherapy could delay or prevent CNS leukemia from occurring.20 For the 16 children in our series who received DJ-MTX-BOMB and IT therapy, the CR length appeared greatly improved; their median remission time was over 21 weeks longer than that of those children not receiving IT drugs (45.5 vs. 24 weeks).…”

Cancer chemotherapy: new strategies for success.

“…However, if chemotherapy was stopped after induction of this so-called complete remission, the disease usually recurred, which indicated the persistence of undetectable tumor cells that multiplied to bring about the relapse. In contrast, continuation of chemotherapy for extended periods beyond those needed to induce remission resulted in long-term, disease-free intervals and, ultimately, in some cases, to unmaintained remissions and apparent cures (5,6). Thus, it appeared that chemotherapy could be used to treat cancer cells that were not clinically obvious and were beyond detection by available diagnostic tests.…”

“…The rationale for this approach can be found in the postinduction, remission maintenance treatment of ALL, in which the survival and cure rates are clearly improved by continuing therapy beyond the point when all recognizable disease is eliminated (5,6). The need for such an approach is clearly demonstrated by the high recurrence rate of distant metastasis in patients undergoing surgery with curative intent for breast cancer, melanoma, or osteogenic sarcoma (I 1, 12).…”

Relapse in childhood acute lymphoblastic leukemia after elective cessation of initial treatment: Failure of subsequent treatment with cyclophosphamide, cytosine arabinoside, vincristine and prednisone (COAP)

“…The planned duration of therapy was 24 months. Rivera and co-workers have demonstrated the necessity and utility of CNS reprophylaxis [8]. We administered such therapy during the second course of lowdose COAP.…”