Diffusion-weighted imaging using 3.0 T MRI as a possible biomarker of renal tumors

Anticancer Res. 2015 Apr;35(4):2351-7.

Abstract

Background/aim: Diffusion-weighted imaging (DWI) allows for differentiation of benign from malignant tumors, histological tumor types and their grade. The aim of the study was to evaluate the capabilities of DWI using 3 Tesla Magnetic resonance imaging (3T MRI) in the preoperative assessment of renal tumors.

Patients and methods: This retrospective study included 143 tumors in 139 patients (130 malignant tumors and 13 benign tumors) that were examined using DWI with b values of 50, 400 and 800 s/mm(2). In all tumors, the lowest value of apparent diffusion coefficient (ADC) in the solid tissue was measured and correlated with the histological finding.

Results: A significant difference between ADCs of malignant and benign tumors was found (p<0.001). Comparison of the most common malignant and benign tumors clear-cell renal carcinoma (CCRCC) grade I and oncocytoma resulted in a difference of borderline significance with a marked overlap (p=0.046). By assessing the histological types of malignant tumors, we detected a significant difference between CCRCC and all other histological types (p=0.048 for chromophobe (CH) RCC, p=0.002 for papillary (P) RCC and p=0.002 for urothelial carcinoma (UC)). Mutual differentiation of other types of carcinomas was not feasible (p=1.0 in all cases). The differences between low-grade (grade I+II) and high-grade (grade III+IV) CCRCC was significant (p<0.001). A significant difference was found even between CCRCC grade I and others (p=0.01 for grade II, p<0.001 for grade III+IV, respectively).

Conclusion: DWI may contribute in distinguishing CCRCC from other histological types and to determinits grade. The method has certain potential for distinguishing benign from malignant tumors; however, differentiation of the most frequently represented types, CCRCC grade I and oncocytoma, remains difficult.

Keywords: Renal tumor; apparent diffusion coefficient; biomarker; diffusion weighted MRI; magnetic resonance imaging.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoma, Oxyphilic / diagnosis
  • Adenoma, Oxyphilic / diagnostic imaging*
  • Adenoma, Oxyphilic / pathology
  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / chemistry
  • Carcinoma, Renal Cell / diagnosis
  • Carcinoma, Renal Cell / diagnostic imaging*
  • Carcinoma, Renal Cell / pathology
  • Contrast Media* / chemistry
  • Diffusion Magnetic Resonance Imaging*
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted
  • Kidney Neoplasms / diagnosis
  • Kidney Neoplasms / diagnostic imaging*
  • Kidney Neoplasms / pathology
  • Male
  • Middle Aged
  • Neoplasm Staging
  • Radiography
  • Retrospective Studies

Substances

  • Biomarkers, Tumor
  • Contrast Media

Supplementary concepts

  • Oncocytoma, renal