Learning objectives
The great majority of cystic renal masses are found incidentally as a result of the use of ultrasonography (US),
computed tomography (CT),
and magnetic resonance (MR) imaging.
Fortunately,
most of these are simple renal cysts that can be easily diagnosed and do not require treatment.
However,
complex cystic renal masses or cyst like tumors are also discovered,
many of which are clearly malignant and need to be surgically removed,
while others may not require surgical intervention.
Therefore,
the proper characterization of these masses is essential...
Background
Benign renal cysts are common in the general population and are detected on CT in up to 50% of patients older than 50 years.
Most renal cysts represent benign renal cortical lesions and do not require any follow-up imaging. However,
as renal cysts become more complex,
it becomes increasingly difficult to make the distinction between benign and malignant lesions,
and also the probability of malignancy increases.
Approximately 10–15% of all renal cell carcinomas can appear as complex cystic lesions on imaging studies [1].
Bosniak classified...
Imaging findings OR Procedure details
One-hundred and ten lesions were Bosniak category I,
II (benign) with thin wall,
no/or thin septations,
no calcifications,
density 0-20HU,
no enhancement after intravenous administration.
[Fig 2-6]
Ten lesions were Bosniak category IIF with calcium,
or high density.
After 2 years follow up no changes were observed.
[Fig.
7-8]
In one case [Fig.
9] of an 82-years-old man,
with chronic renal failure because of kidney and ureter stones and hydronephrosis,
there was a severe skepticism if the lesion should be placed in category IIF (complicated...
Conclusion
Most renal cystic lesions are benign fulfilling Bosniak I criteria and require no further evaluation.
Bosniak IIF requires at least a two year follow up.
Lesions at Bosniak III–IV are treated as malignant and require nephrectomy.
Sometimes there is a significant difficulty in making the distinction between category IIF and III lesions,
and this is one of the drawbacks of the system.
In those cases there is a tendency to upgrade category IIF lesions to category III that need renal removal.
Therefore,
the proper evaluation...
Personal Information
L.
Metaxa1,
I.
Tsifountoudis2,
P.
Kiryttopoulos1,
F.
Metaxas2,
M.
Michaelidou2,
A.
Theodosiou1,
P.
Sountoulides1,
I.
Kalaitzoglou2;
1GH Veria/GR,
2Thessaloniki/GR
Email corresponding author :
[email protected]
References
1. Koga S,
Nishikido M,
Inuzuka NS,
et al.
An evaluation of Bosniak’s radiological classification of cystic renal masses.
BJU Int 2000;86:607–609
2. Curry N.,
Cochran S.,
Bissada N.,
Cystic Renal Masses: Accurate Bosniak Classification Requires Adequate Renal CT,
AJR2000;175:339–342
3. Bosniak MA.,
The use of the Bosniak classification system for renal cysts and cystic tumors,
J Urol.
1997 May;157(5):1852-3.
4. Harisinghani M.,
Maher M.,
Gervais D.,
McGovern F.,
Hahn P.,
KartikJhaveri,
Varghese J.,
Mueller P.,
Incidence of Malignancy in Complex Cystic Renal Masses (Bosniak...