Introduction

Sex cord stromal tumors (SCSTs) represent a heterogeneous group of rare gonadal tumors that represent approximately 10% of all gonadal tumors during childhood.1 SCSTs develop from the non-germ cell component of the gonads. Physiologically, these cells support germ cell maturation in their microenvironment. Furthermore, they may produce sex hormones, and so may the corresponding tumors. The rarity and heterogeneity of SCSTs, and the difficulty in the correct histopathologic classification leave a significant uncertainty with regard to the optimal clinical. Of note, some subtypes are associated with constitutional genetic aberrations (e.g. DICER1 mutations) and thus, they may be part of an underlying cancer predisposition and require specific follow-up.2–4
This paper presents the internationally harmonized recommendations for the diagnosis and treatment of children and adolescents with SCSTs, established by the EXPeRT within the EU-funded project called PARTN-ER - Paediatric Rare Tumours Network - European Registry. The methodology of the process – development under the auspices of the European Reference Network for Paediatric Cancer (ERN PaedCan) - has been already described (Orbach et al, PBC 2021)