Paediatric gastrointestinal neoplasia

Paediatric gastrointestinal tumours and tumour-like lesions are uncommon, even within paediatric surgical pathology practice, with malignant tumours extremely rare in this age group. Furthermore, when present, such malignancies are likely to be non-Hodgkin B-cell lymphoma or stromal tumours rather than carcinoma, in contrast to adult practice. The most frequent gastrointestinal tumour-like lesions in childhood are mucosal polyps, which may be adenomatous, juvenile or hamartomatous in nature, and their presence, especially when multiple, may indicate underlying predisposition syndromes, which may also have manifestations in other organ systems. Whilst children may be affected with underlying conditions which increase the risk of carcinoma development, such as adenomatous polyposis or inflammatory bowel disease, malignant transformation rarely occurs during childhood. Primary gastrointestinal tumours, other than Burkitt-type lymphoma affecting the small intestine and caecum, are most likely to be appendiceal neuroendocrine tumours (carcinoid) and gastrointestinal stromal tumours, although a range of other lesions may rarely present with primary gastrointestinal involvement including vascular malformations and haemangioma, ganglioneuroma and inflammatory myofibroblastic tumours. In the setting of any apparently primary gastrointestinal tumour in childhood, the possible association with underlying systemic predisposition syndromes should be considered.