The Value Of Color Doppler Ultrasound In The Diagnosis And Staging Of Renal Cell Carcinoma Compared With CT And Pathologic Results

As a common malignant of kidney cancer, primary renal cell carcinoma(RCC) has a high incidence, nearly 2% to 3% of all malignant human tumors, and about 80% to 90% of kidney cancer. It usually occurs at the age of over 40, and males is about three times more than women. Early diagnosis and accurate staging is directly related to prognosis and the choice of clinical treatment because of that symptoms of RCC occurs late and high mortality of RCC.By observing the success rate of surgery and the specific survival rate of the patients with renal cell carcinoma, Robson stages was formulated in accordance with the relation between the scope of the primary tumor and the signs of human anatomy. According to Robson stages:The tumor is confined to the kidney membrane at stageⅠ; Fat around the kidney or the ipsilateral adrenal gland has been violated, But the tumor is confined to Gerota'S fascia at stageⅡ; Renal vein, inferior vena cava (IVC), or the local lymph node has been violated at stageⅢ; The surrounding organs (except the adrenal gland) has been infiltrated by the tumor or distant metastasis at stageⅣ. The relation between Robson stage of RCC and prognosis has been confirmed. Someone reported that the 5-year survival rate is about 70% at stageⅠ, and only 10% at stageⅣ.With high resolution on spatial density, CT examination is sensitive and accurate in the diagnosis of renal tumors, and can describe the lesion size﹑tissue density﹑mass of the shape﹑borders﹑strengthen characteristics﹑ violation of perirenal fat and renal vein, but CT examination is expensive and radiation damage. With the update of color Doppler ultrasound equipment and the improvement of checking technology, Ultrasound has obvious advantages in the early detection and diagnosis of kidney cancer. There are more and more cases detected by ultrasound general examination, the detection rate of asymptomatic renal tumors has increased from 10%–15% to 50% or more. renal cell carcinoma of which diameter is more than 1cm can be found by ultrasound. Color Doppler ultrasound can show the location﹑size﹑shape﹑internal echo﹑internal structure and the blood supply of the lesion clearly, can also determine the extent of the tumor﹑local invasion and distant metastasis, and it is low-cost﹑easy operation﹑no radiation damage﹑short-term repetitive inspection.as the most commonly used examination method of renal cell carcinoma, ultrasound also has high accuracy in staging of RCC. Simple application of 2D is able to accord with the pathological staging in majority of RCC, but it is difficult to show small vein tumor thrombus or newly formed low echo tumor thrombus. CDFI can make accurate staging on stageⅡ﹑Ⅲof RCC by observing blood signal changes caused by tumor thrombus. Besides, tumor invasion sites can often found tumor-related blood flow signal, so CDFI play an important role on determine the Infiltration to the surrounding tissue of RCC. By observing the echoes of perirenal adipose capsule or the organization connected with the mass like liver﹑spleen﹑musculi psoas major and other organs or tissue related with the RCC, to determine whether there are violations of tumor tissue. Therefore, there are great significance of color Doppler ultrasound for the differential between the RCC periods.This study was designed to improve the level of color Doppler ultrasound in diagnosis and staging of RCC, in order to guide clinical treatment to choose the right plan and to assess the prognosis of patients. We selected 120 cases of RCC patients under the color Doppler ultrasound﹑CT examination preoperatively, all cases were proved by pathologic examination. By analyzing the general sonogram features contained the location﹑size﹑border﹑internal echo﹑blood flow signals of renal cell carcinoma, assorting all the cases according to the internal echo and blood flow signal, we obtained the qualitative diagnosis rate of color Doppler ultrasound on RCC. The study showed that there were 58.3% low-echo and equal echo of RCC﹑23.3% high-echo of RCC and 18.3% mixed echo of RCC. Ultrasound can diagnose the vast majority of low-echo RCC(56/58)﹑equal echo(10/12)﹑high-echo(20/28)﹑mixed echo(18/22), the respective diagnosis rate was 96.9%﹑83.3%﹑71.4%﹑81.8%. The blood flow signals of RCC can be divided into four types by Color Doppler ultrasound: the hold-ball type﹑star-point type﹑rich in blood type and less blood type, the respective diagnosis rate was 100%﹑77.8%﹑100%﹑47.4%. All cases were staged by ultrasound and CT examination according to Robson stages, then compared the results with the pathological. We found that both ultrasound and CT examination had a high coincidence rate on the diagnosis and staging of RCC. There was no significant difference in between ultrasound and CT examination (p>0.05). The staging coincidence rate of ultrasound was 82.5%, a little more than CT(79.2%). Without taking into account tumor stage, we analysed the information of violations of various anatomical structures which obtained by browsing the surgical records﹑other checks and pathological description. We found that color Doppler ultrasound is superior to CT at the aspect of showing renal capsule﹑renal fascia﹑psoas major muscle﹑tumor thrombus in renal vein or inferior vena cava. Combined ultrasound with CT could improve the the level of the diagnosis and stage of RCC.Come to the conclusions:(1)Both ultrasound and CT examination have a high coincidence rate on the diagnosis and staging of RCC, no statistically significant difference, coincidence rate of diagnosis is respectively 86.7%,91.7%, coincidence rate of staging is respectively82.5%,79.2%.(2)Ultrasound is superior to CT at the aspect of showing renal capsule﹑renal fascia﹑psoas major muscle﹑tumor thrombus in renal vein or inferior vena cava, on the contrary, CT is sensitive than ultrasound in showing perirenal lymph and distant organs contain gas or bone ,such as lung﹑brain or bone.(3)Ultrasound and CT may be better to determine preoperative staging of renal cell carcinoma, contributing to a more accurate assessment of surgical resectability for renal cell carcinoma. There is a great significance in guiding clinical surgical options and prognosis of patient.(4)Combined ultrasound with CT, could improve the the level of the diagnosis and stage of RCC.