How Competent is Computed Tomography in Characterization and Grading of Renal Malignancies: Our Experience

Year 2018, Volume: 71 Issue: 3, 187 - 193, 31.12.2018

Zehra Akkaya Ayşegül Gürsoy Çoruh , Elif Peker , Kayhan Çetin Atasoy Derya Gökmen , Cemil Yağcı

https://izlik.org/JA67NT36LA

Abstract

Objectives: Accurate diagnosis of renal tumors is critical for obtaining the best treatment and longest possible survival. The purpose of this study is to evaluate computed tomography (CT) parameters of renal masses in order to assess benign and malignant nature as well as accurate grading.

Materials and Methods: Fifty three cases with multiphasic abdominal CTs between 2006 and 2011 were included. Precontrast, corticomedullary, nephrographic postcontrast phase images were retrospectively examined for lesion characteristics, enhancement degrees with regard to the normal renal parenchyma and abdominal aorta, blinded to the surgical results. To compare independent groups for categorical variables chi-square, for metric variables Mann-Whitney U tests were used. Receiver operating characteristics curve analysis was performed to group renal tumor subtypes and when applicable the cut-off values were determined, “Youden” index was calculated. p<0.05 was considered as statistically significant.

Results: Forty six of 53 lesions were malignant, 32 (57.1%) of them clear cell renal cell carcinomas (CCRCC), 5 (9.4%) papillary and 1 (1.9% chromophobe cell RCC. Cystic changes, calcifications and larger size were more pronounced in CCRCC (p< 0.05). The mean sizes of Fuhrman grade I and grade 4 tumors were 31.2±10.9 mm and 63.8±29.8 mm respectively. Fuhrman grades were significantly correlated with the lesion size at diagnosis (p<0.05). To discriminate CCRCC from other masses and CCRCC from other RCC subtypes, 44.5 HU cut-off as the early wash-in showed 81.3%-76.2 % and 81.3%-87.5% sensitivity and specificity, respectively. To discriminate CCRCC among other subtypes the threshold levels calculated from early wash-in, tumor/aorta, tumor/renal parenchyma densities at corticomedullary and nephrographic phases showed equal sensitivity and specificity (83.5% and 75% respectively).

Conclusion: Large size at diagnosis, cystic changes and calcifications were useful parameters to discriminate CCRCC from other tumors and other RCC subtypes. A cut- off value of 44.5 HU for early wash-in could discriminate CCRCC with high sensitivity and specificity. Size and cystic changes showed significant correlation with RCC subtypes and Fuhrman grades.

Keywords

Kidney , Renal Cell Carcinoma , Multiphasic Computed Tomography , Clear Cell Variant

Ethical Statement

Ethics Committee Approval: Retrospective study. Informed Consent: Retrospective study. Peer-review: Externally and internally peer-reviewed. Authorship Contributions Concept: Z.A., C.Y., Design: Z.A., C.Y., Data Collection or Processing: Z.A., C.Y., Analysis or Interpretation: Z.A., D.G., Literature Search: Z.A., E.P., A.G.Ç., Writing: Z.A. Conflict of Interest: No conflict of interest was declared by the authors. Financial Disclosure: The authors declared that this study received no financial support.

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Böbrek Malignitelerini Karakterizasyon ve Derecelemede Bilgisayarlı Tomografi Ne Kadar Yetkin: Bizim Deneyimimiz

https://izlik.org/JA67NT36LA

Abstract

Giriş: Uygun tedavi ve mümkün olan en uzun sağkalım için böbrek tümörlerinde doğru tanı kritik önem taşır. Bu çalışmanın amacı böbrek kitlelerinde benign-malign ayrımı ve doğru dereceleme için bilgisayarlı tomografi (BT) parametrelerinin ayrıntılı incelenmesidir.

Gereç ve Yöntem: Çalışmaya 2006-2011 yılları arasında ünitemizde multifazik BT incelemesi gerçekleştirilmiş 53 hasta dahil edilmiştir. Prekontrast, kortikomedüller ve nefrografik faz görüntülerinde kitle, normal parankim ve abdominal aorta kontrastlanma dereceleri ile lezyonların görüntüleme bulguları, retrospektif ve cerrahi sonuçlara kör olarak değerlendirilmiştir. İstatistiksel analizde bağımsız gruplarda kategorik değişkenler için kikare, ölçülebilir değişkenler için Mann-Whitney U testi, kullanılmış, renal tümör tiplerini ayırmada alıcı işletim karakteristiği eğirisi analizleri gerçekleştirilmiştir, uygun parametrelerde eşik değer belirlemede “Youden” indeksi hesaplanmıştır. p<0,05 istatistiksel olarak anlamlı kabul edilmiştir.

Bulgular: Elli üç lezyondan 46 tanesi malign olup bunların 32’si (%57,1) berrak hücreli renal karsinom (BHRK), 5’i (%9,4) papiller ve 1 tanesi (%1,9) kromofob hücreli renal karsinomdu. İntralezyoner kistik değişiklikler, kalsifikasyonlar ve büyük boyut BHRK’de daha fazlaydı (p<0,05). Furhman derece 1 tümörlerde ortama boyut 31,2±10,9 mm iken, derece 4 tümörlerde 63,8±29,8 mm olarak saptandı. Tanı anındaki kitle boyutları ile Fuhrman dereceleri arasında anlamlı ilişki gözlendi (p<0,05). Erken wash-in eşik değeri olarak 44,5 HÜ alındığında BHRK’leri diğer renal kitlelerden ve diğer renal karsinom alt tiplerinden ayırmada duyarlılık ve özgüllük değerleri sırasıyla %81,3-%76,2 ile %81,3-%87,5 olarak bulundu. Tüm renal karsinomlar arasında BHRK’lerin ayrımı için bakılan parametrelerden elde edilen eşik değerlerine göre erken wash-in, kortikomedüller ve nefrografik fazlarda tümör/ aorta ve tümör/ normal renal parankim dansite oranları eş duyarlılık ve özgüllükte bulundu (sırasıyla; %83,5 ve %75).

Sonuç: Tanıda büyük boyut, kistik değişiklikler ve kalsifikasyon BHRK’leri diğer renal kitelerden ve diğer renal karsinom alt tiplerinden ayırmada kullanışlı parametreler olarak bulundu. Ayrıca erken wash-in eşik değeri olarak 44,5 HÜ alındığında BHRK’ların yüksek duyarlılık ve özgüllükle doğru tespit edilebileceği saptandı. Büyük boyut ve intralezyoner kistik değişiklikler, BHRK alt tipi ve yüksek Fuhrman derecesi ile korele bulundu.

Keywords

Böbrek , Renal Hücreli Karsinom , Mulifazik Bilgisayarlı Tomografi , Berrak Hücreli Variant

Ethical Statement

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