The effect of radio- and chemotherapy on auxological parameters was investigated in 30 children treated for acute lymphatic leukemia (ALL) or non-Hodgkins lymphoma (NHL). Growth velocity was decreased during the first year of treatment. Catch-up growth was insufficient during the following years. Thus, the whole group experienced a loss of height of 0.49 +/- 1.1 SD at 6.8 +/- 2.6 years after diagnosis. Height and growth velocity were not different between children who received 18 or 24 Gy cranial irradiation; however, growth velocity was significantly lower in children who were treated for more than 2 years or who had the more intensive chemotherapeutic protocol. Evaluation of the growth hormone (GH) response to pharmacological stimulation revealed reduced GH peaks in 47% of the patients, but there was no correlation of GH peak with growth or treatment parameters. In conclusion, the impairment of growth in children after treatment for ALL or NHL might be related to the intensity and duration of chemotherapy.