Longitudinal growth and final height in long-term survivors of childhood leukaemia

Abstract

Survival of children with acute lymphoblastic leukaemia (ALL) has increased considerably in recent years and data on the spontaneous growth and final height of these children are conflicting. Therefore, we analysed the longitudinal growth and final height in 52 survivors (33 females, 19 males) of childhood ALL. These children were diagnosed and treated in a single institution, all remained in first remission and were submitted to cranial irradiation with either 2400 or 1800 cGy. None of the patients received testicular or spinal irradiation. Median age at diagnosis was 4.2 (range 1.3–9.6) years in the first group (2400 cGy) and 3.9 (0.8–10.5) years in the second (1800 cGy). Standing height was measured at diagnosis, at the end of treatment (median 3.1 years after diagnosis), 6, 12, 24 months after the end of treatment, and finally at the completion of growth. In girls a significant decrease of mean height standard deviation score (SDS) during treatment and a catch up in growth after the end of therapy was followed by a second period of reduced growth. Mean final height SDS was significantly lower than the value at diagnosis in both groups of girls, but only in males treated with 2400 cGy. Mean overall loss in height SDS from diagnosis to final heigth was higher in females (−1.24) than in males (−0.40) (P=0.009). Females <-4 years of age at diagnosis showed a higher loss in final height than females >4 years. An unchanged or improved final height was evident in 8 cases, the other 44 cases showed a final height decrease between −0.1 and −2 SDS in 36 and >-2 SDS in 8, 6 of whom were females <-4 years at diagnosis and only 1 a female >4 years. Only females treated at a younger age showed a final height lower than midparental height (−5.7±1.8 cm,P<0.01), particularly those treated with 2400 cGy (−7.5±2.5 cm,P<0.05). Menarche occurred earlier than in the normal population (11.5±1.2 years) with no differences between the two radiation dosages.

Conclusion

Females, notably young girls, treated for ALL show a greater decrease in the final height than treated males. Early sexual maturation may contribute to the decrease in the final height. A better growth pattern seems to be shown by patients irradiated with the lower dosage.