《腎臟囊性占位》

1、精選ppt腎臟囊性占位2013-11精選pptIntroductionIgnore, Follow or ExciseRadiological InterpretationCalcificationHyperdense or High signalSeptationsEnhancementMultiloculatedNodularityWall thickeningRole of BiopsyDr Bosniaks opinionBosniak Classification of Renal Cystic Disease精選ppt精選ppt Even on gross examination

2、a cystic renal cell carcinoma (left) may be indistinguishable from a complicated cyst (right) 精選pptIgnore, Follow or ExciseRenal cysts can be classified according to the Bosniak classification depending on their features. Type I cysts are simple cysts.Type II are the minimally complicated cysts. Typ

3、e I and II can be ignored. Type II F are probably benign, but need to be followed. Type III and IV both are surgical lesions. Type IV is inevitably malignant and in the type III group about 80-90% turn out to be malignant as well.In our communication with the clinicians it is important, that we expl

4、ain the significance of our findings and the meaning of the classification in terms of: Ignore (type I and II), Follow (type IIF) or Excise (type III and IV).So in this lecture we will only talk about Ignore, Follow or Excise.For those who want to see the original Bosniak classification, look at the

5、 table which is presented at the end of the lecture.精選ppt精選ppt Radiological Interpretation Although the final differentiation of cystic renal masses is based upon histologic diagnosis, there are imaging findings that tell you that a cyst is not a simple cyst and whether it is probably benign or mali

6、gnant. The following imaging features indicate that a cyst is NOT simple:- Calcification- Hyperdense / high signal- Septations- Multiple locules- Enhancement- Nodularity / wall thickening精選ppt Differentiation is based upon histologic diagnosis, but Imaging is a reliable means for differentiating ben

7、ign from malignant cystic lesions 精選pptThe table on the left summarises these imaging features together with the management consequences: Ignore, Follow or Excise.When we look at these imaging features, we have to realise, that the most worrisome portion of a cystic mass should be used in deciding a

8、ppropriate management. So when the findings are discordant either within one examination or using different radiological examinations, the lesion should be managed based upon the most aggressive imaging findings.When we look at the table on the left, we can say that we are pretty good with the first

9、 3 parameters (calcification, hyperdens and septations), because we are correct in about 95% of the cases.The other four are even more easy, because when you have any of these (enhancement, multiloculated, nodularity or wall thickening), the lesion is almost always a surgical lesion.Regarding follow

10、 up, there are no rules at the moment.One could do a follow up at 6 months and if the lesion is stable then double the follow up time.We will now discuss all these imaging features in detail.精選ppt精選pptCalcification The most important thing is a good description of the type of calcifications.We can i

11、gnore small amounts of calcification that are smooth, septal or if it is milk of calcium, which moves to the lowest point with positional changes.We have to make sure, that no enhancement (= All lesions that show enhancement and lesions with wall thickening or nodularity of the wall outside the calc

12、ifications should be excised.We can follow lesions with thick or nodular calcification without any enhancement. 精選ppt精選pptBenign calcifications: small punctate and milk of calcium.Ignore On the left we see a cystic lesion. There is a small punctate calcification that we can ignore.On the bottom of t

13、he cyst there is a layer of calcium typical for milk of calcium.This is also a benign calcification that we can ignore. 精選pptLEFT: NECT with a smooth linear calcification and nodular calcification.RIGHT: Enhanced CT shows enhancement . Excise On the left a patient with nefrolithiasis.There is also a

14、 cystic lesion with linear and nodular calcification . If there were only these linear calcifications we could ignore the lesion. In case of nodular calcification we can follow it, if there is no enhancement.In this case however we see enhancement, so this lesion has to be excised. 精選pptOn CT hyperd

15、ense means: 20 HU on a NECTOn MRI hyperintense means all that has higher signal intensity than water on a T1 weighted image. Hyperdensity or hyperintensity usually indicates hemorrhage or high protein content of the cyst.Ignore all lesion with sharp margins; lesions On US they have to be clearly cys

16、ticFollow all lesions that are totally intrarenal, because you can not appreciate the wall and follow all lesions 3 cm, because there is at the moment not much experience with these lesions. All these lesions must show no enhancement.Excise all lesions that are poorly defined or heterogenous or show

17、 enhancement. Also when ultrasound shows that the lesion is solid, the lesion should be excised. Hyperdense or High signal精選pptLEFT: NECT shows a lesion with a density of 27 HU.IgnoreRIGHT: MRI shows a intrarenal lesion that is hyperintense on T1: higher signal than water. Follow On the left we see

18、a hyperdens cystic lesion on CT and a hyperintense lesion on a T1-weighted MR.Both lesions have a sharp margin and are homogeneous, although there is some noise in the CT image.On the enhanced scans (not shown) the lesions didnt show any enhancement.We therefore can ignore the lesion on the left and

19、 we have to follow the lesion on the right, because it is totally intrarenal. 精選pptSeptations Ignore thin septations ( Follow all septations that are only slightly greater than hairline. They still have to show no enhancement.Excise all septations that are thick, irregular or nodular and all septati

20、ons that show enhancement. 精選pptLEFT: thin, smooth septation.IgnoreRIGHT: thick enhancing septation . Excise On the left we see 2 casesThere is a cystic lesion with a thin smooth non enhancing septation that we can ignore.The other case is a thick enhancing septation that has to be excised. 精選pptCys

21、tic lesion with thick septation and a nodule . Excise The ultrasound image on the left shows a thick septation.There is also a nodule in the wall of the cyst.So we have two reasons to excise this cystic lesion. 精選pptEnhancement Enhancement is our best predictable sign of malignancy.So we have to exc

22、ise all lesions, that clearly show enhancement.The only exception is infection. 精選pptSignificant enhancement: Unenhanced CT: 44 HU (left)Enhanced scan: 61 HU (right) . Excise Enhancement is defined as follows: Increase in Hounsfield Units of the mass after contrast injection: 10-15 HU = indeterminat

23、e 15 HU = vascularityOn MR: 15% = enhancement = surgical精選pptEnhanced CT shows enhancement of a thick wall and a central area.excise The case on the left doesnt shows much on the NECT.However when we give contrast we can appreciate a thick wall and we see enhancement both of the wall and of a centra

24、l area in the medial part of the cystic lesion.We should never see this in an benign cyst, so this is a surgical lesion. 精選pptMultiloculated Masses with three or more septa are not called multiseptated but multiloculated.All multiloculated lesions should be excised, unless there is clear evidence of

25、 infection. 精選pptMultiloculated cystic mass on US and on CT. Excise In the adult, the two most common multiloculated masses are MLCN (multilocular cystic nephroma) which is usually benign, but sometimes malignant and MLRCC (multilocular renal cell carcinoma) which is always malignant. On imaging the

26、re is no way that we can separate these two and therefore, all multiloculated masses are surgical (unless infection). 精選pptMultilocular renal cell carcinoma (left) and a multilocular cystic nephroma (right) Even the pathologist can not separate the usually benign multilocular cystic nephroma from th

27、e malignant multilocular renal cell carcinoma on gross specimen .The differentiation is based on the histology of the epithelial cells lining these locules.So all multilocular renal masses have to be excised. 精選pptNodularity Ignore: noneFollow: only very small nonenhancing nodules, and follow carefu

28、llyExcise: all other nodular lesions 精選pptVery small non enhancing nodules.Follow The case on the left shows very small nodules on a CECT and a T2WI.From all the other images we could tell that they were not enhancing.So we can probably follow this lesion.If they start to grow or show any enhancemen

29、t, then we have to excise the lesion. 精選pptCystic lesion with a big enhancing nodule . Excise On the left an easy case.There is a big nodule with enhancement, so this lesion has to be excised.Even if there was no enhancement, the lesion still had to be excised. 精選pptT2WI shows a multiloculated cysti

30、c mass with multiple nodules . Excise The case on the left is a T2WI with Fatsat.We see multiple nodules so this mass has to be excised.It doesnt matter whether or not these nodules enhance. 精選pptWall thickening All lesions with a thickened wall, with or without enhancement, should be excised, unles

31、s there is clear evidence of infection. In these latter cases the lesions should be followed. 精選pptTwo cysic lesions with a regular thick wall . Excise On the left we see two renal lesions that are cystic.The lesion on the far left clearly shows a thickened wall. This is easy to appreciate because p

32、art of the lesion is extrarenal.The cystic lesion next to it is totally intrarenal, which makes it harder to appreciate, but there is wall tickening.So both lesions have to be excised, whether there is enhancement of the wall or not.The only exception would be if there were evident signs of infectio

33、n. 精選pptCystic lesion with a thick irregular enhancing wall . Excise The cystic lesion on the left is clearly a surgical lesion.It has a thick irregular wall, it is exophytic and shows enhancement. 精選pptRole of Biopsy In the literature there are different opinions concerning the role of biopsy in re

34、nal cystic lesions.Here we provide Dr Bosniaks opinion.A different opinion is given by Dr Lang in the artice on CT-guided biopsy of indeterminate renal cystic masses (Bosniak 3 and 2F): accuracy and impact on clinical management (see references) 精選ppt Dr Bosniaks opinion Biopsy plays a limited role.

35、 Only in case of clinical suspicion that the mass is inflammatory (pyuria, etc.) or there is radiological evidence suggesting inflammation (such as perinephric fat stranding), puncture is acceptable. When the outcome is infection, the lesion can be treated and followed. Although considered rare, needle track spread of tumor is an underestimated risk.A core biopsy of the wall of a cystic lesion (benign or malignant) can cause it to rupture and spill its contents into the surrounding tissues. A negative biops