The Application Value Of Contrast-enhanced Ultrasound In The Preoperative Evaluation Of T1 Renal Cell Carcinoma

Background:Renal cell carcinoma（RCC）has become an important threat to the health and life of the Chinese people.According to statistics,among new RCC tumors in recent years,T1 stage accounts for more than 60%-80%,and the onset age has a trend of younger age.The key to the choice of surgical methods for T1 RCC is to evaluate the prognosis before surgery.Non-invasive imaging examination is very important for the evaluation of tumor stage,grade and other prognostic factors.contrast-enhanced ultrasonography（CEUS）,as an imaging examination with many advantages,has similar sensitivity and specificity to CT in the diagnosis and differential diagnosis of renal cell carcinoma.In recent years,more and more clinicians pay attention to CEUS.It has a broad prospect in preoperative evaluation of T1 RCC.Purpose:To compare the advantages of contrast-enhanced ultrasound（CEUS）with conventional ultrasound in the diagnosis of T1 RCC,and to explore the application value of CEUS in the preoperative evaluation of T1 RCC.Methods:A total of 66 patients with localized RCC of T₁N₀M₀clinical stage in our hospital from September 2017 to October 2022 were collected.The conventional ultrasound and CEUS image features of each case were retrospectively analyzed,and the qualitative and quantitative parameters were recorded.The diagnostic results of CEUS and conventional ultrasound in tumor lesions were evaluated and compared from multiple angles.The differences of each parameter between clear cell renal cell carcinoma and non-clear cell renal cell carcinoma were analyzed,and the differences of each parameter between the high pathological grade group and the low pathological grade group in clear cell renal cell carcinoma were analyzed in subgroups.All parameters were analyzed statistically.Results:（1）Comparison of conventional ultrasound and contrast-enhanced ultrasound diagnosis.The average score of lesion apparent score of CEUS mode was 2.61±0.68,which was higher than that of conventional ultrasound（1.45±0.91）.Taking the maximum diameter of the tumor in the postoperative pathological data as the reference standard,the intraclass correlation efficient（ICC）coefficient of enhanced CT,CEUS and conventional ultrasound was 0.852,0.835 and 0.806,respectively.The detection rate of tumor pseudocapsule by CEUS was 42.4%（28/66）,which was higher than 7.5%（5/66）by conventional examination.The above differences were statistically significant（P<0.05）.The sensitivity and accuracy of CEUS in detecting necrosis and cystic degeneration in the tumor were 94.1%and 83.3%,respectively,which were higher than 70.1%and 72.7%of conventional ultrasound.The sensitivity,specificity and accuracy of CEUS were 57.14%,90.38%and 83.33%,respectively,which were higher than 35.71%,84.61%and 74.24%of conventional ultrasound.（2）The image features of cc RCC group and ncc RCC group were compared.Most cc RCC patients showed hyperenhancement（40/54,74%）,while most ncc RCC patients showed hypoenhancement（9/12,75%）.The perfusion mode of cc RCC group was"fast forward"（49/54,91%）,and that of ncc RCC group was"slow forward"（7/12,58%）or"fast forward"（5/12,42%）."Fast regression"（32/54,59%）or"slow regression"（22/54,41%）was the most common regression pattern in cc RCC group,and"fast regression"（11/12,92%）was the most common pattern in ncc RCC group.The display rate of pseudocapsuce in cc RCC group was 50%（27/54）,which was higher than that in ncc RCC group（8.3%,1/12）.The△TP of cc RCC（-0.24±0.40%）was lower than that of ncc RCC（0.06±0.49%）.The△PI of cc RCC group（0.35〈0.43〉%）was higher than that of ncc RCC group（-0.06〈0.64〉%）.The above data were statistically significant（P<0.05）.There was no significant difference in the other qualitative and quantitative indicators between the two groups.（3）Grouping analysis of image features of low-grade and high-grade cc RCC showed that the display rate of pseudocapsule in low-grade CCRCC was 56%（26/46）,which was higher than that in high-grade CCRCC（12.5%,1/8）.All the patients in the high-grade group were male（8/8,100%）,and 65%（30/46）of the patients in the low-grade group were male.There were significant differences between the above two groups（P<0.05）.There was no significant difference in the other qualitative and quantitative indicators between the two groups.Conclusions:（1）In the diagnosis of T1 RCC,CEUS has advantages over conventional ultrasound in the obvious display of lesions,the accuracy of lesion size measurement,the display rate of pseudocapsule,the display of necrosis and cystic degeneration area,and the display of invasive characteristics of lesions.（2）CEUS has certain clinical value in preoperative evaluation of pathological type and grade of T1 RCC.