Ayşegül Gürsoy ÇORUH, Elif PEKER, Orhan Avcı

Bosniak Tip 3 ve Tip 4 Kistlerin Multifazik Bilgisayarlı Tomografi İle Kantitatif Değerlendirilmesi

Amaç: Bu çalışmada multifazik bilgisayarlı tomografide (BT) ortalama dansite-net kontrastlanma değerlerinin ve net kontrastlanma yüzdelerinin Bosniak tip 3 ve 4 kistlerin ayırımındaki tanısal değerinin değerlendirilmesi amaçlanmıştır. Gereç ve Yöntem: Hastanemizin Görüntü Arşivleme ve İletişim Sisteminde (PACS) “Bosniak kist” anahtar kelimesi kullanılarak hasta popülasyonunu belirlemek için arama yapıldı. Çalışmaya multifazik BT incelemesi bulunan Bosniak tip 3 ve 4 renal kiste sahip yirmi dokuz hasta dahil edildi. Kontrastsız, kortikomedüller ve nefrogram fazlarında ortalama dansite değerleri ölçüldü. Bu lezyonların net kontrastlanma değerleri ve net kontrastlanma yüzdeleri hesaplandı. Kist duvarı/septada kalsifikasyon varlığı, renal ven trombozu veya lenfadenopati varlığı ve bu kompleks kistik lezyonların ortalama çapı değerlendirildi. Bulgular: Bosniak tip 4 kistler, kortikomedüller ve nefrogram fazlarında Bosniak tip 3 kistlere göre anlamlı derecede daha yüksek ortalama kontrastlanma değerine sahipti (sırasıyla; 167,2±53,6 HU, 99,8±43 HU; p=0,001, p=0,023). Bosniak tip 3-4 lezyonları ayırmada net kontrastlanma değerleri ve yüzdesi açısından anlamlı farklılık saptandı (sırasıyla; p=0,003, p=0,015). ROC eğri analizinde Bosniak tip 4 kistlerin ayrımında kortikomedüller fazda >131 HU kontrastlanma değeri için %82 duyarlılık %83 özgüllük oranları hesaplandı. Bu eşik değer için eğri altında kalan alan 0,848±0,081 (%95 güven aralığı: 0,68-1) olarak bulundu. Sonuç: Bosniak tip 4 kistler, tip 3 kistlere göre daha fazla net kontrastlanma değeri ve net kontrastlanma yüzdesine sahiptirler. Kortikomedüller fazda >131 HU değeri, Bosniak tip 4 kistlerinin tanımlanmasında belirleyici değer olacaktır.

The Quantitative Evaluation of Bosniak Category 3 and 4 Cysts on Multiphasic Computer Tomography

Objectives: The aim of this study is to evaluate the diagnostic value of mean and net enhancement attenuation values, net enhancement percentage in discrimination of Bosniak category 3 and 4 lesions on multiphasic computer tomography (CT). Materials and Methods: A search was performed through the PACS system using the key word “Bosniak cyst” to identify candidates for the study population. Twenty nine patients with Bosniak category 3 and 4 enrolled the study. Enhancement values were measured on precontrast, corticomedullary and nephogram phases. Net enhancement attenuation value and net enhancement percentage were calculated. The presence of calcification on cyst wall/septa, renal vein thrombosis or lymphadenopathy and mean diameter of these complex cystic lesions were utilized. Results: Bosniak category 4 cysts had a significantly higher mean attenuation value compared with that of Bosniak category 3 cysts on corticomedullary and nephogram phases (167.2±53.6 HU, 99.8±43 HU; p=0.001, p=0.023; respectively). Significant differences were observed between two pathologies with regard to net enhancement value and net enhancement percentage (p=0.003, p=0,015; respectively). By the use of ROC curve analysis, the cut off value of 131 HU for the mean attenuation value of Bosniak category 4 cyst on corticomedullary phase had the appropriate combination of sensitivity of 82% and specificity of 83% with the area under the cure being 0.848±0.081 (95% confidence interval: 0.68-1). Conclusion: Bosniak category 4 cysts had larger net enhancement value and enhancement percentage. A value of >131 HU on corticomedullary phase can be a predictor value for Bosniak category 4 cysts.

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Mousessian PN, Yamauchi FI, Mussi TC, et al. Malignancy Rate, Histologic Grade, and Progression of Bosniak Category III and IV Complex Renal Cystic Lesions. AJR Am J Roentgenol. 2017;209:1285-1290.
Harisinghani MG, Maher MM, Gervais DA, et al. Incidence of malignancy in complex cystic renal masses (Bosniak category III): should imaging-guided biopsy precede surgery? AJR Am J Roentgenol. 2003;180:755-758.
Bosniak MA. The current radiological approach to renal cysts. Radiology. 1986;158:1-10
Israel GM, Bosniak MA. An update of the Bosniak renal cyst classification system. Urology. 2005;66:484-488.
Sevcenco S, Spick C, Helbich TH, et al. Malignancy rates and diagnostic performance of the Bosniak classification for the diagnosis of cystic renal lesions in computed tomography - a systematic review and meta-analysis. Eur Radiol. 2017;27:2239-2247
Bosniak MA. The use of the Bosniak classification system for renal cysts and cystic tumors. J Urol. 1997;157:1852-1853.
Kim DY, Kim JK, Min GE, et al. Malignant renal cysts: diagnostic performance and strong predictors at MDCT. Acta Radiol. 2010;51:590-598.
Webster WS, Thompson RH, Cheville JC, et al. Surgical resection provides excellent outcomes for patients with cystic clear cell renal cell carcinoma. Urology. 2007;70:900-904.
Smith AD, Allen BC, Sanyal R, et al. Outcomes and complications related to the management of Bosniak cystic renal lesions. AJR Am J Roentgenol. 2015;204:550-556.
Park HS, Lee K, Moon KC. Determination of the cutoff value of the proportion of cystic change for prognostic stratification of clear cell renal cell carcinoma. J Urol. 2011;186:423-429.
Whelan TF. Guidelines on the management of renal cyst disease. Can Urol Assoc J. 2010;4:98-99.
Song C, Min GE, Song K, et al. Differential diagnosis of complex cystic renal mass using multiphase computerized tomography. J Urol. 2009;181:2446- 2450.
Xie P, Yang Z, Yuan Z. Lipid-poor renal angiomyolipoma: Differentiation from clear cell renal cell carcinoma using wash-in and washout characteristics on contrast-enhanced computed tomography. Oncoll Lett. 2016;11:2327- 2331.