Squamous cysts arising from segmental renal dysplasia.

BACKGROUND

Cystic renal dysplasia is a common developmental abnormality of fetal kidney, featuring disorganized lobar organization, undifferentiated mesenchyma, metaplastic cartilage, persisting immature collecting ducts, and cystic changes. Cystic renal dysplasia can affect the entire kidney or in a segmental fashion. Squamous cysts within the dysplastic kidney, however, are exceedingly rare; only two cases have been reported in the English literature, dating back about 25 years.

CASE REPORT

This report is, to our knowledge, the second to describe this unusual finding and may be viewed as confirmation of the entity. In the two previous cases, squamous cysts arose in a generalized cystic dysplasia background; the one we are reporting instead happened in a case of segmental cystic renal dysplasia.

CONCLUSIONS

We further proved, with fluorescent in situ hybridization (FISH), the negativity of 12p amplification in this lesion, supporting the notion that this lesion is not intrarenal teratomatous in nature.