Atypical cysts and carcinomas of the kidneys in the phacomatoses. A quantitative dna study using static and flow cytometry

Abstract

Reported are the pathologic features of atypical cysts and/or renal cell carcinomas found in the kidneys of four patients having either tuberous sclerosis or Hippel-Lindau disease. In addition, cellular DNA contents of the cells lining the atypical cysts and comprising the carcinomas were quantitated using both static and flow cytometric techniques. These studies showed that cysts lined by atypical epithelial cells are frequently present in renal parenchyma adjacent to the renal carcinomas, and that the cytologic features of atypical cells lining the cysts were essentially the same as the cytologic features found in the adjacent well-differentiated, renal cell carcinomas. DNA quantitative studies revealed that both the renal cell carcinomas and the atypical cyst lining cells had the same DNA indices and were essentially DNA euploid. In this patient group these findings are consistent with the hypothesis that the atypical cyst lining cells evolve into the renal cell carcinomas; however, they do not prove this proposed but likely sequence.

Renal lesions in von Hippel–Lindau disease: immunohistochemical expression of nephron differentiation molecules, adhesion molecules and apoptosis proteins

“…Malignancy was found in 96% of the solid lesions and 11% of the cystic lesions, in agreement with previous studies 5 , 8 , 17 . Our observations confirm previous findings concerning the frequency of multifocal and often bilateral renal involvement and the wide range of renal lesions in von Hippel–Lindau patients, which consist of simple clear cell cysts, atypical clear cell cysts, cystic and solid clear cell carcinoma, and fibrous nodules 5 , 8 , 17 , 18 . Benign and atypical cystic clear cell lesions are found only in patients with von Hippel–Lindau disease 19 .…”

“…The presence of lesions representing all stages of this proposed model of tumour progression in the same kidney of a given patient, as found in our study and others, 5 , 8 , 17 , 18 has been said to support this hypothesis. Quantitative studies of DNA in von Hippel–Lindau patients showing a similar DNA content in atypical cysts and renal cell carcinomas were also reported 18 . However, some arguments have been developed against this model.…”

Management of renal cell carcinoma in von Hippel–Lindau disease

“…Extensive tumour formation may occur when inadequate control and treatment is given, as in patient 10. But our general finding of a relatively low number of renal lesions confirms the low frequency reported in other studies [7,13,15,34]. In addition, mild manifestation of renal involvement in VHL is also illustrated by the absence of RCC during long-term follow-up in patient II-13 ( Fig.…”

Huge renal angiomyolipomas in tuberous sclerosis complex

“…10 The absence of a fat component or presence of calcification raises the suspicion of a malignant tumour like RCC, which occurs in 1-2% of TSC. 20 However, there are other less common fatcontaining renal tumours, like Wilms tumor, 21 oncocytomas, 22 lipomas and liposaracomas, which may rarely cause confusion. 23 Although AML is regarded as a benign tumour, a malignant variant of AML, epithelioid angiomyolipoma, has been reported.…”

“…A CT scan is particularly useful in detecting haemorrhage 10 . The absence of a fat component or presence of calcification raises the suspicion of a malignant tumour like RCC, which occurs in 1–2% of TSC 20 . However, there are other less common fat‐containing renal tumours, like Wilms tumor, 21 oncocytomas, 22 lipomas and liposaracomas, which may rarely cause confusion 23 …”