FINAL HEIGHT AFTER TREATMENT FOR CHILDHOOD ACUTE LYMPHOBLASTIC-LEUKEMIA - COMPARISON OF NO CRANIAL IRRADIATION WITH 1800 AND 2400 CENTIGRAYS OF CRANIAL IRRADIATION

We analyzed growth and final heights in 127 patients (68 female patien ts) treated for childhood acute lymphoblastic leukemia. Central nervou s system prophylaxis included either no cranial radiation therapy (CRT ) (n = 38), irradiation with 1800 centigrays (cGy) (n = 36), or irradi ation with 2400 cGy (n = 53). None of the patients received spinal irr adiation. Mean (+/- SEM) age at diagnosis was 6.4 +/- 0.25 years, mean height standard deviation score (SDS) at diagnosis was 0.28 +/- 0.12, and mean age at final height was 18.26 +/- 0.19 years.The change in he ight SDS between diagnosis and achievement of final height was signifi cant for all treatment groups: -0.49 +/- 0.14, no CRT; -0.65 +/- 0.15, 1800 cGy; and -1.38 +/- 0.16, 2400 cGy. Irradiated patients had a gre ater loss in height SDS compared with the nonirradiated patients (p <0 .01), and those treated with 2400 cGy CRT had a greater decrease in fi nal height SDS than the patients treated with 1800 cGy (p <0.01). Both younger age and female sex were significantly associated with a great er decrease in height SDS in the patients treated with CRT; girls less -than-or-equal-to 4 years of age at diagnosis had a mean loss in heigh t SDS that was more than twice that observed for others treated with t he same dose of CRT. Thus, although modern regimens for acute lymphobl astic leukemia (no CRT or 1800 cGy CRT) appear overall to have only a modest impact on final height, patients, especially girls, treated wit h 1800 cGy CRT of a young age remain at risk for clinically significan t growth failure.