Medical cost of curing childhood acute lymphoblastic leukaemia.

Between 1970 and 1979 acute lymphoblastic leukaemia was diagnosed in 378 children at this hospital. The outcome for the 181 survivors was examined six or more years after diagnosis to assess morbidity in an unselected group of long term survivors. One hundred and thirty seven of the survivors were in first remission and probably cured (group I). Forty four (group II) had had one or more relapses, some of whom, who had isolated extramedullary relapses, also have a good chance of cure. In group I 136 patients had prophylactic cranial or craniospinal irradiation, while patients in group II, in addition to having that treatment, received local testicular (17) or craniospinal radiation (seven) for testicular or central nervous system relapse. Eight had additional prophylactic cranial radiotherapy after bone marrow relapse, and six had total body irradiation before bone marrow transplantation. The incidence of clinically important growth and endocrine morbidity was 20% in group I and 68% in group II. The morbidity in patients in group I was mainly attributable to early pubertal maturation. In group II 30 patients had growth failure, of whom 19 had gonadal failure from testicular or total body irradiation, 14 had growth hormone deficiency after doses of cranial irradiation of over 2400 cGy, and 10 had spinal growth impairment after craniospinal irradiation. Two also had early pubertal maturation. Five out of six patients who received total body irradiation had multiple endocrine deficiency. Neuropsychological sequelae of treatment were seen in 40 (42%) of 96 schoolchildren in group I and in 12 (38%) of 32 schoolchildren in group II. Postinfective sequelae of treatment were found in patients in both groups. These results show that the survivors who were in their first remission had a 42% residual morbidity related to treatment compared with an 82% morbidity in the survivors of one or more relapses who had multiple treatments.