Diagnostic value of strain elastography for differentiation between renal cell carcinoma and transitional cell carcinoma of kidney

PURPOSE

The objective of our study was to prospectively evaluate the diagnostic performance of strain elastography for differentiation between renal cell carcinomas (RCCs) and transitional cell carcinomas (TCCs) of kidney.

METHODS

A total of 99 consecutive patients who were referred to our hospital because of a newly diagnosed solid renal mass suspicious for malignancy on radiological screenings were evaluated with sonography, including strain elastography. Strain elastography was used to compare the stiffness of the renal masses and renal cortex. The ratio of strain in a renal mass and nearby renal cortex was defined as the strain index value. Mean strain index values for RCCs and TCCs were compared, and mean strain index values between histological subtypes of RCC were also compared.

RESULTS

Although TCCs were smaller than RCCs (p < 0.001), there were no significant differences in gender distribution and mean age of the patients, and mean probe-tumor distance between RCC and TCC. The mean strain index value ±SD for TCC (5.18 ± 1.12) was significantly higher than the value for RCC (4.04 ± 0.72; p < 0.001). Mean strain index value for papillary cell carcinomas (4.09 ± 0.45) was slightly higher than that for clear cell carcinomas (3.85 ± 0.78): however, the difference was not statistically significant (p = 0.51).

CONCLUSIONS

Strain elastography can be used as a valuable imaging technique for preoperative differentiation between RCC and TCC of kidney.

Conditional Survival and Associated Prognostic Factors in Patients with Upper Tract Urothelial Carcinoma after Radical Nephroureterectomy: A Retrospective Study at a Single Institution

Purpose

The purpose of this study is to evaluate the changes of conditional survival (CS) probabilities and to identify the prognostic parameters that significantly affect CS over time post-surgery in upper tract urothelial carcinoma (UTUC) patients.

Materials and Methods

A total of 330 patients were examined in the final analysis. Primary end point was conditional cancer-specific survival (CSS), overall survival (OS), and intravesical recurrence-free survival (IVRFS) after surgery. The Kaplan-Meier method was used for calculation of CS. Cox regression hazard ratio model was used to determine the predictors of CS.

Results

UTUC patients who had already survived 5 years after radical nephroureterectomy had a more favorable CS probability in all given survivorships compared to those with shorter survival times. Patients with unfavorable pathologic features showed a higher increment of 5-year conditional CSS and OS compared to their counterparts. For 5-year conditional CSS, several factors, including high-grade tumor, lymphovascular invasion, and tumor location showed significant association with risk elevation over time. Only age remained as a predictor of 5-year conditional OS with increased risk in all given survivorships. For 5-year IVRFS, no variables remained as significant predictive factors over time after surgery.

Conclusion

Our study provides valuable information for practical survival estimation and relevant prognostic factors for patients with UTUC after surgery.

Transitional cell and clear cell renal carcinoma: differentiation of distinct histological types with multiphase CT

BACKGROUND

Transitional cell carcinoma (TCC) may mimic renal cell carcinoma (RCC) when it develops in a similar location, therefore, differentiation with imaging techniques might be challenging. Preoperative differentiation may have a significant role indicating the type of surgical treatment (nephrectomy vs. ureteronephrectomy).

PURPOSE

To retrospectively analyze the differences in the contrast enhancement of TCC and RCC.

MATERIAL AND METHODS

Images of 20 RCC and 12 TCC (mean ages, 62.3 ± 14.1 and 67.4 ± 12.0 years, respectively) were analyzed from patients who underwent multiphase computed tomography (CT) examinations following 1.5 mL/kg non-ionic contrast agent administration. Unenhanced corticomedullary (30-45 s), nephrographic (70-90 s), and excretory (300-480 s) phases were imaged. The attenuation characteristics of RCC and TCC were compared to the attenuation of the normal renal cortex.

RESULTS

Significant differences were found in the attenuation ratios between RCC or TCC in the corticomedullary (P = 0.040) and nephrographic (P = 0.004) phases using three regions of interest (ROIs) of 10 mm(2) size. If measuring ROIs comprising the complete tumor lesion instead of three small ROIs, no significant difference was observed in the attenuation ratios between RCC in TCC in any phases.

CONCLUSION

Our study reports significant attenuation differences between RCC and TCC in the corticomedullary and nephrographic phases by multiphase CT. The findings underscore the importance of multiphase CT in the differentiation of these two different entities. Using multiple small (three) ROIs is more accurate than measuring the whole tumor attenuation.

Robot-assisted surgery for the treatment of upper urinary tract urothelial carcinoma

Robot-assisted laparoscopic surgery is increasingly used in urologic oncologic surgery. Robotic nephroureterectomy is still a relatively new technique. As upper tract urothelial carcinoma is a rare disease, intermediate- and long-term outcome data are scarce. However, robotic nephroureterectomy does seem to offer advantages to open and laparoscopic counterparts, with comparable short-term oncologic and functional outcomes. Here the authors review the robotic surgical management of upper tract urothelial carcinoma, with a review of the steps and tips on making this approach more widely adoptable.