[Tubulo-papillary tumors of the kidney. Clinical, histologic and cytogenetic aspects. 15 new cases].

Between 1987 and 1992, we operated on 15 patients with tubulopapillary tumours (TPT) of the kidney, corresponding to 10% of all renal cancers operated during this 5-year period, which brings the total number of published cases to 418. TPT differ from non-tubulopapillary tumours in several ways. The medical imaging findings may differ when the tumour is not necrotic (20 to 30% of cases). The histology differs not only in terms of the tumour architecture, but also by the frequent association (9/15 cases) with other ipsilateral or contralateral renal anomalies: 2 bilateral tumours, 3 tumours associated with multiple cysts and 4 multifocal tumours. These characteristics, combined with the finding of 12 familial cases suggest a genetic origin for TPT, especially as the genetic abnormalities detected (tri-or tetrasomy 17) differ from the anomalies usually detected in non-tubulopapillary tumours (anomalies of 3p and 5q). This study is the first to report familial cases of TPT. The prognosis of these tumours, generally better than that of non-tubulopapillary tumours, suggests the possibility of conservative surgery when the diagnosis can be established preoperative or at operation.