[Primary carcinoid tumor and horseshoe kidney: potential association]

The authors present the ninth case of primary carcinoid tumour arising in a horseshoe kidney. The diagnosis and treatment were delayed due to the benign cystic appearance of the initial lesion. This exceptional association must be kept in mind, as horseshoe kidney is associated with an increased risk of malignant tumours, especially for carcinoid tumours. The minimally aggressive nature of these tumours generally allows limited surgical resection.