Association between birth weight and risk of nonneurological childhood cancers: a systematic review and meta-analysis

Objectives This systematic review aims to synthesize the available literature to determine the association between birthweight and the risk of nonneurological childhood cancers. Methods We conducted a systematic search of PubMed, Web of Science, and Scopus databases up to May 2023 to identify observational studies. Heterogeneity between studies was evaluated using the I 2 statistics. Publication bias was assessed using Begg and Egger tests. We calculated the odds ratio (OR) or risk ratio (RR) with a 95% confidence interval (CI) using a random-effects model. Results Of 11 034 studies retrieved from the search, 56 studies (including 10 568 091 participants) were eligible. The ORs (95% CI) of low (<2500 g) versus normal birthweight (2500–4000 g) and childhood cancers were as follows: leukemia, 0.92 (0.77–1.11); acute lymphoblastic leukemia, 0.82 (0.72–0.94); acute myeloid leukemia, 0.98 (0.77–1.24); lymphoma, 0.99 (0.47–2.10); Hodgkin, 0.79 (0.61–1.03); non-Hodgkin, 0.85 (0.60–1.20); neuroblastoma, 1.34 (1.14–1.58); retinoblastoma, 0.95 (0.68–1.32); rhabdomyosarcoma, 0.86 (0.61–1.20); embryonal, 0.97 (0.66–1.43); alveolar, 1.92 (0.43–8.51); and Wilms tumor, 1.01 (0.83–1.24). The ORs (95% CI) of high (>4000 g) versus normal birthweight and childhood cancers were as follows: leukemia, 1.30 (1.18–1.42); acute lymphoblastic leukemia, 1.27 (1.16–1.39); acute myeloid leukemia, 1.13 (0.98–1.30); lymphoma, 1.69 (0.72–3.94); Hodgkin, 1.22 (1.02–1.46); non-Hodgkin, 1.22 (0.80–1.86); neuroblastoma, 1.20 (1.02–1.41); retinoblastoma, 1.17 (0.93–1.48); rhabdomyosarcoma, 1.07 (0.90–1.27); embryonal, 1.22 (1.00–1.49); alveolar, 1.02 (0.46–2.27); and Wilms tumor, 1.49 (1.34–1.67). Conclusion This meta-analysis identified high birth weight as a potential risk factor for some childhood cancers, while low birth weight might be protective against a few.