Primary cutaneous lymphoblastic lymphoma in children: series of eight cases with review of the literature.

AIM: Primary cutaneous lymphoblastic lymphoma is a rare but well recognised tumour predominantly of childhood. In this study we examine eight cases of cutaneous lymphoblastic lymphoma in children, which is the largest series to date of tumours confined to the skin with or without local lymph nodes (stage I or II) but without systemic disease at diagnosis. METHODS: The clinical history and histology from the eight cases were reviewed together with a panel of immunohistochemical stains to confirm lineage and diagnosis. RESULTS: Seven of the eight cases were confirmed as B-lymphoblastic lymphoma (B-LBL) of the skin, with the eighth case representing a CD4+/CD56+ plasmacytoid dendritic cell tumour. The cases were all stage I or II, and all patients received systemic chemotherapy after full staging investigations to exclude systemic disease at diagnosis. All patients remained in complete remission at the time of last follow-up of between 3 and 9 years from diagnosis. CONCLUSIONS: Lymphoblastic lymphoma may present primarily in the skin without systemic manifestation, with the majority of such cases representing B-LBL. A rare case of childhood CD4+/CD56+ plasmacytoid dendritic cell tumour with similar blastic morphology is also described. Full staging investigations are mandatory at diagnosis to exclude systemic disease. Cases confined to stage I or II at diagnosis carry an excellent prognosis with appropriate systemic chemotherapeutic treatment.