Rare blood neoplasm masking as a concerning soft tissue tumour: blastic plasmacytoid dendritic cell neoplasm

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive malignancy with fewer than 100 paediatric cases reported. This report details a boy who presented in young childhood with a skin lesion on his left buttock that clinically resembled a sarcomatous lesion. Histopathological work-up including flow cytometry, immunophenotyping and phenotypic correlation were consistent with the diagnosis of BPDCN. The diagnosis of BPDCN radically altered this patient's treatment pathway. The case highlights the importance of multidisciplinary team evaluation in soft tissue masses and careful consideration of alternative diagnoses. For this child, the diagnosis of BPDCN prevented an extensive local resection.