This is a description of a novel combination of chromogenic multiplex immunohistochemistry, digital
pathology, computer-aided cell detection and topographical analysis of tumor tissue to allow a detailed study
of the immune infiltrate. This is applied to a rare clinical case, where a tumor sample is available from an
infant with metastatic neuroblastoma at the point of spontaneous regression. This allowed detailed analysis
of the immune infiltrate, including spatial distribution and phenotype of lymphoid and myeloid populations,
with a distinction between heterogeneous areas within the intra- and extra- tumoral immune
microenvironments. The mechanism of spontaneous regression in congenital neuroblastoma is poorly
understood, but the data obtained suggested an immune-mediated phenomenon, characterised by an
adaptive T cell driven response with a significant delayed-type hypersensitivity (granulomatous)
component.