Carcinoid in a horseshoe kidney. Morphology, immunohistochemistry, and cytogenetics

Renal carcinoids are very rare neoplasms. We were able to culture and subsequently karyotype a carcinoid located in the isthmus of a horseshoe kidney, which revealed the following chromosomal pattern: 47,XX, + 13[8]/46,XX,t(13;14)(q31;q11.2)[5]/46,XX[2]. The DNA index was 1. Our results, compared with the sparse data from the literature, suggest that carcinoid of the kidney has no cytogenetic aberrations in common with carcinoids from other anatomical sites reported. On the other hand, numerical and structural aberrations of chromosome 13 seem to play a crucial role in the development of metanephric-derived renal tumors.