Background        The role of insulin growth factor 1 (IGF-1) in the etiology of cancer is an ongoing subject of debate. In adults, IGF-1 levels might be associated to colon cancer, thyroid cancer, multiple myeloma, breast cancer, and prostate cancer. Only few (small) studies have been performed in children, with contrary results. We aimed to describe IGF-1 standard deviation scores (SDS) in a large cohort of newly diagnosed pediatric cancer patients.

Methods               During a 2 year period, we identified pediatric patients newly diagnosed with leukemia, lymphoma, sarcoma or brain tumor (excluding those with a brain tumor in the hypothalamic-pituitary region), in the largest pediatric cancer center in Europe, the Princess Máxima Centre, the Netherlands. IGF-1 levels were measured at diagnosis (±35 days). Data were collected on tumor type, anthropometrics, administered medication (steroids or chemotherapy), general well-being, and thyroid function.

Findings               Of 289 eligible patients, in 192 (66·4 %), IGF-1 was measured at diagnosis. Mean IGF-1 SDS was -0·59 (SD 1·25). No effect was found of previous administered drugs on IGF-1 SDS. We found significant lower IGF-1 SDS in leukemia patients compared to brain tumor patients (-0·82 vs. 0·12) and sarcoma patients (-0·82 vs. -0·17). Patients with a general well-being classed as “Good” had significant higher IGF-1 SDS compared to patients whose general well-being was classed as “Medium” or “Poor”.

Interpretation     This unique cohort study demonstrates non increased IGF-1 SDS at diagnosis in pediatric cancer patients. IGF-1 SDS seem to be affected by tumor type and general well-being. Future research may focus on prospective large cohorts evaluating IGF-1 (SD) levels in the years prior to cancer diagnosis, to further analyze its contribution to the etiology of childhood cancer.