Renal cell carcinoma- diagnosis by computed tomography

In approximately 10% of cases, renal cell carcinoma (RCC) could present as a fluid- filled cystic mass. There are three mechanisms by which RCC may become cystic: extensive cystic necrosis, intrinsic cystic growth and origin from the epithelium lining a simple renal cyst. Simple renal cysts are very common. Uncommonly these cysts are complicated by hemorrhage, infection and possibly ischemia. The goal of the radiologist in evaluating these cystic lesions is to distinguish malignant neoplastic cystic masses from non-neoplastic complicated cysts so that appropriate management can be undertaken: RCC is best treated by surgical excision while non-neoplastic complicated cysts do not require surgery. The radiologic findings in these cystic masses which must be carefully evaluated include calcification, abnormal density, septations, nodularity, wall thickening and enhancement.     

囊性肾癌15例分析

目的 提高对囊性肾癌的认识。方法 对１９８２～１９９７年收治的１５２列囊性肾癌的临床特点、影像学、病理学特征及治疗预后情况进行回顾性分析。结果 术前影像学检查提示囊肿相关肾占生病变１２例,其中伴钙化５例,单纯性囊肿３例;术中活检发现癌变２例,多房囊肿性肾癌１例。１５例均行根治性肾切除术。１３例获随访,存活时间３个月～８年,平均３．２年。结论 囊性肾癌有其独特的临床,影像及病理学特征,对不符合典型单     

肾癌误诊为肾囊肿11例

目的 提高对囊肿相关性肾癌的诊治水平。方法 回顾性分析误诊为肾囊肿的11例肾癌的临床特点、影像学、病理学特征。结果 11例患者平均误诊3.0年,其中实质性肾癌3例,囊性肾癌8例,术中活检2例。均行根治性肾切除术。结论 肾癌影像学复杂多变,重视体检发现的肾囊肿的随访,警惕漏诊肾癌。     

CA9 as a molecular marker for differential diagnosis of cystic renal tumors

ObjectiveCA9 is proven to be a powerful marker for clear cell renal cell carcinoma. The studies on CA9 have been limited to solid renal cell carcinomas (RCC). We have conducted a study of CA9 expression in renal cystic tumors. The purpose of the present study was to extend the utility of CA9 for cystic renal tumors.Materials and methodsImmunohistochemistry and enzyme-linked immunosorbent assay (ELISA) were used to detect CA9 expression in cystic renal tumors. Forty-three cystic renal tumors (22 benign and 21 malignant) were included for the immunohistochemical staining. Thirty-six patients with a cystic renal mass (20 malignant and 16 benign cystic tumors) were studied to measure CA9 level in the fluid by ELISA. Sixteen cysts (9 malignant and 7 benign cysts) were subjected both to immunohistochemistry and CA9 measurement in the fluid.ResultsUsing immunohistochemical staining, all the benign cystic renal tumors including the 18 simple cyst and 4 benign multilocular cystic nephromas did not express CA9. All 13 cystic clear cell RCC were scored as strong staining for CA9. For 8 multilocular clear cell RCC, 7 were scored as strong staining for CA9 and the other one was negative. There was a significant difference in positive percentage (P < 0.001) between the 2 groups of malignant and benign cysts. For the 16 benign cysts, the mean concentration of CA9 in the fluid of cyst was 162 ± 133 pg/ml (median: 0 pg/ml; range: 0–2140 pg/ml). For the 20 malignant renal cystic tumors, the mean concentration of CA9 in the fluid of cyst was 2043 ± 62 pg/ml (median: 2,140 pg/ml; range: 1,112–2,140 pg/ml). There was a significant difference in mean concentration of CA9 between the two groups of malignant and benign cysts (P < 0.001). The presence or absence of CA9 expression measured by immunohistochemistry and ELISA test was concordant in 14 out of 16 cases (88%).ConclusionsMalignant cystic renal tumors expressed strongly CA9 while the benign renal cysts did not express CA9. CA9 can be detected in the fluid of malignant cystic renal tumors. CA9 is a promising molecular marker to differentiate the malignant cystic renal tumors from the benign cysts.     

Cyst-associated renal cell carcinoma: Clinicopathologic characteristics and evaluation of prognosis in 27 cases

BACKGROUND: No consistent clinicopathologic characteristics of cyst-associated renal cell carcinoma (CRCC) have previously been determined. METHODS: In total, 768 patients with renal cell carcinoma (RCC) underwent radical or partial nephrectomy. Renal cell carcinoma was classified as CRCC in 27 of these patients (3.5%, subdivided into RCC originating in a cyst and cystic RCC), clear-cell RCC in 662 patients (86.2%), chromophobe cell renal carcinoma in 36 patients (4.7%) and papillary RCC in 43 patients (5.6%) according to the criteria of the World Health Organization. RESULTS: The pathologic stage and nuclear grade were usually lower in those with CRCC (low stage/low grade; 89%/96%) or chromophobe cell renal carcinoma (low stage/low grade; 89%/80%) than in those with clear-cell RCC (low stage/low grade; 59%/65%) or papillary RCC (low stage/low grade; 53%/69%). Of the 27 CRCC patients, only 19 (70%) could be diagnosed through preoperative imaging studies. Patients with CRCC showed a favorable prognosis (survival rate: 95% at 1 year, 89.7% at 3 years and 84.4% thereafter) and, especially among the patients with RCC originating in a cyst, no cancer-related death was observed. Comparing the survival among four types of RCC, a favorable outcome was observed in cases of CRCC or chromophobe cell renal carcinoma compared with clear-cell RCC or papillary RCC (clear vs chromophobe: P = 0.002; chromophobe vs papillary: P = 0.019; clear vs cyst-associated: P = 0.001; papillary vs cyst-associated: P = 0.00079). CONCLUSIONS: In cases of CRCC, the disease was usually detected at lower stages and grades and therefore the prognosis was better than in cases of other types of RCC. Preoperative diagnosis of this disease was very difficult, especially in cases of RCC originating in a cyst.     

Expression of matrix metalloproteinase in the fluids of renal cystic lesions

PURPOSE: Cystic lesions of the kidney are common conditions usually diagnosed by imaging. Although simple cysts are easy to diagnose, preoperative diagnosis of a complicated cystic lesion can be difficult. There is little information available on the biological activity of cystic fluid and associations with clinicopathological findings. We analyzed the expression of matrix metalloproteinase (MMP) in the fluids of benign and malignant renal cystic lesions to clarify matriolytic activities in the cyst. MATERIALS AND METHODS: Included in this study were 22 samples of cystic fluids from renal cystic lesions, including 14 benign cysts and 8 cystic renal cell carcinomas. MMP-2 and 9 was determined in fluids using gelatin zymography and enzyme-linked immunosorbent assay. RESULTS: MMP-2 expression was ubiquitously observed on zymography except for 2 benign cysts associated with acquired cystic disease of the kidney. MMP-9 was detected in 7 of 8 carcinomas but in only 2 of 14 benign cysts (p <0.01). The concentration of MMP-2 and 9 was significantly higher in cystic carcinomas than in benign cysts (p <0.01). CONCLUSIONS: Our data show that MMPs were detectable in cystic fluids in the presence of renal cystic changes. MMP-2 and 9 are more abundant in cystic carcinoma fluids than in benign cystic fluids. These observations suggest that matriolytic enzymes in renal cystic fluid reflect biological aggressiveness and in part explain the pathogenesis of renal cystic lesions.     

经皮囊内入路电切去顶术治疗单纯性肾囊肿16例报告

目的:评估经皮囊内入路电切去顶术治疗单纯性肾囊肿的疗效,以探讨低侵袭性、彻底的肾囊肿治疗方式。方法:我院于2011年4月~2013年12月采用经皮肾穿刺囊肿去顶术治疗单纯性肾囊肿患者16例。患者平均年龄59(23~78)岁;囊肿位于左肾13例,右肾3例。囊肿直径平均8.2(5.2~12.8)cm。术中在超声定位下应用经皮肾穿刺技术配合双极电切镜切除游离于肾脏外侧的囊壁,术后留置引流管2d。结果:14例患者手术顺利完成,囊肿完全消失。意外发现1例肾细胞癌,二期行肾部分切除术;1例因出血中转开放手术。平均手术时间68(15~125)min。平均随访15(1~32)个月,未见复发。结论:单纯性肾囊肿可以用经皮肾穿刺去顶术安全解决。此技术优于腹腔镜肾囊肿去顶减压术,避免了多个trocar的安置及广泛的肾周剥离,降低了手术难度。     

肾囊肿内肾癌(附四例报告)

目的 探讨肾囊肿内肾细胞癌的诊断和治疗。方法 总结６８例肾囊肿患者资料,对４例合并肾细胞癌者的资料进行分析。结果 ４例患者中术前明确诊断者２例,术中发现者２例。行肾癌根治切除术２例,行囊壁和肿物切除术２例,４例随访６～１２个月未见复发,结论 Ｂ超发现肾囊肿增长快或囊内有病变时应行ＣＴ平扫和增强扫描。怀疑肾囊肿内肾癌时应行手术探查。     

Cystic renal cell carcinoma diagnosed by cystofiberscopy

A 64-year-old man suffered from hypertensive syncope and was admitted to Branch Hospital, Faculty of Medicine, The University of Tokyo. On admission he had no symptoms; however, two renal cysts of about 5 cm in diameter were found in his left kidney. Cystofiberscopy with a thin optical fiberscope was performed in addition to puncture and cystography. Cytology revealed class I, but the wall surface of the lower cyst was uneven, fluid-filled, colloid-like and white-gray compared with that seen in the upper cyst. It was diagnosed as renal cell carcinoma (RCC) and left nephrectomy was performed (5 cm in diameter, RCC, papillary tubular, common, clear cell subtype, G2>G1, INF beta, pT2, pMx, pV0, ew(-)).     

囊性肾癌的诊治及预后(附31例报告)

目的提高囊性肾癌的诊治水平，提高对于囊性肾癌的认识。方法回顾性分析1994年6月-2004年6月收治的31例囊性肾癌患者的流行病学、病理学、临床表现、影像学特征及临床治疗资料，并与TNM分期构成与囊性肾癌组相同的21例非囊性肾癌比较预后。结果囊性肾癌无特征性的临床表现，术前影像学检查可以提供诊断线索，经病理确诊肾癌囊性变19例，多囊性肾癌9例，单纯性囊肿癌变3例。17例行根治性肾切除术，14例行单纯性肾切除术。术后21例获得随访，生存时间平均38个月。总体上与非囊性肾癌的预后尤统计学差异。站论囊性肾癌是一类在影像学和大体病理上具有囊性改变的肾癌的统称，由3种病理学类型构成，术前正确鉴别各亚型是选择手术方式和判断预后的关键。     

Multilocular cystic renal cell carcinoma: clinicopathological features and preoperative prediction using multiphase computed tomography

Study Type – Diagnostic (exploratory cohort) Level of Evidence 2b What’s known on the subject? and What does the study add? Multilocular cystic renal cell carcinoma (MCRCC), defined according to the 2004 WHO classification, has good prognosis, which is not affected adversely by large tumour size or advanced stage. Thus nephron‐sparing surgery is proposed when MCRCC is suspected by preoperative radiologic criteria. The present study confirms the low malignant potential of MCRCC. Additionally, the results of the present study provide a simple, useful criteria using a Bosniak classification and Hounsfield unit on multiphase computed tomography images to differentiate MCRCC from other cystic RCC.

OBJECTIVE

? To analyse the clinicopathological and radiological features of multilocular cystic renal cell carcinoma (MCRCC) and to determine the preoperative factors differentiating MCRCC from other cystic RCC (CRCC).

PATIENTS AND METHODS

? The medical records of 53 patients with complex cystic renal masses evaluated by multiphase computed tomography (CT), surgically removed and confirmed as sporadic RCC were reviewed. ? Of these 53 patients, 23 were classified as having MCRCC and 30 as other CRCCs, defined as RCCs with extensive cystic change or cystic necrosis. ? Another 22 patients were treated for complex cystic renal masses presumed to be RCC and diagnosed as having benign cyst.

RESULTS

? Benign cysts and MCRCCs were significantly more likely to be of Bosniak classification III than other CRCCs (77% vs 61% vs 27%, P= 0.001). ? The mean Hounsfield unit (HU) during the corticomedullary phase (CMP) was significantly higher in other CRCCs, with HU ≥38 having 83% sensitivity and 80% specificity for predicting other CRCCs. ? In a multiple regression model, Bosniak classification and mean HU during CMP were independent factors predictive of other CRCCs. ? In the 41 patients with masses >4 cm in diameter, the combination of Bosniak classification IV and HU ≥38 during CMP showed 63% sensitivity, 96% specificity, 91% positive predictive value and 80% negative predictive value, yielding 2% false‐positive and 15% false‐negative rates.

CONCLUSIONS

? The mean HU during CMP and Bosniak classification can differentiate MCRCC from other CRCCs. ? This could help in selecting an appropriate surgical method, such as nephron‐sparing surgery, for complex cystic renal masses >4 cm.     

Cystic renal cell carcinoma,suspected because of lack of regression of renal cysts after renal transplantation in a dialysis patient with acquired renal cystic disease

A 34-year-old man who had been on dialysis for about 6 years, and had acquired renal cystic disease, received a renal transplantation. However, in spite of the success of the transplantation, one area without cyst regression was observed in the original kidney. Therefore, carcinoma was suspected and nephrectomy was performed. Histology revealed cystic renal cell carcinoma (RCC). No case of cystic RCC occurring in a dialysis patient has previously been reported. Cystic RCC should be suspected in a cystic mass in the original kidney which does not regress after successful renal transplantation. Received: August 23, 2002 / Accepted: November 25, 2002 Acknowledgments We thank Dr. Shigehiko Sato, Department of Internal Medicine, Tonami General Hospital, who referred this patient to us. Correspondence to:I. Ishikawa     

Cystadenocarcinoma of the kidney: a profile of 13 cases

Cystadenocarcinoma is an uncommon variant of renal cell carcinoma that is cystic in appearance. Our experience with 13 of these tumors is presented. The biological behavior was similar to renal cell carcinoma in general, although a greater proportion presented as stage I lesions. Computerized tomography and cyst aspiration may be helpful to differentiate these tumors from simple cysts.     

囊性肾癌诊治体会

目的 提高囊性肾癌的诊治水平. 方法 回顾分析10例囊性肾癌患者术前影像学特点、病理特征和治疗方法.男7例,女3例.年龄38～74岁,平均56岁.患侧腰酸3例,体检偶然发现7例,有肾囊肿病史者2例.囊腔直径3.5～8.2 cm.术前B超检查诊断为肾癌6例,CT诊断为肾癌7例.8例术中行冰冻病理:肾细胞癌6例,未发现恶性倾向2例.10例均行根治性肾切除术. 结果 术后病理诊断:肾透明细胞癌9例,颗粒细胞癌1例.病理学分型:肾癌囊性坏死6例,多房囊性肾癌2例,肾囊肿恶变型2例.8例随访6个月～5年,6例无瘤存活,2例分别于术后13、20个月死于肿瘤转移. 结论 重视囊性肾癌独特的影像学特点、病理学特征,术中行冰冻病理检查,是提高囊性肾癌诊治水平的关键.     

Laparoscopic evaluation of indeterminate renal cysts: long-term follow-up

PURPOSE: We present our long-term follow-up of patients who have undergone laparoscopic evaluation for their indeterminate renal cysts, specifically reporting those patients who were found to have cystic renal-cell carcinoma (RCC) and assessing the safety and efficacy of the procedure. PATIENTS AND METHODS: Fifty-seven patients with indeterminate renal cysts (28 Bosniak category II and 29 Bosniak category III) underwent laparoscopic evaluation between July 1993 and July 2000. A transperitoneal laparoscopic localization and aspiration of the cyst, cytologic analysis, and biopsy of the cyst wall and base were performed. A total of 11 patients were found to have cystic RCC. Patients with malignancy have been followed for a mean of 40 months (range 6-70 months), and five patients had 5 years or more of follow-up. RESULTS: Eleven patients (19% of the total) were found to have cystic RCC. Three of these patients had Bosniak category II cysts, and eight had category III cysts. All tumors were low grade (I or II), and the stages were T1-2, Nx-0, M0. There has been no evidence of laparoscopic port site or renal fossa tumor recurrence, local recurrence, or metastatic disease to date in these patients. There is no cancer-specific mortality. CONCLUSIONS: Long-term follow-up indicates that laparoscopic evaluation of indeterminate renal cysts is not associated with an increased risk of port site or retroperitoneal or peritoneal recurrence of RCC. It may save a patient from undergoing open surgery and should be considered as a diagnostic option for patients with indeterminate renal cysts.     

Native Renal Cysts and Dialysis Duration Are Risk Factors for Renal Cell Carcinoma in Renal Transplant Recipients

Urinary tract cancers are the third most common cancers in renal transplant recipients (RTX). This study examined the impact of dialysis duration and native renal cyst(s) (NRC) on renal cell carcinoma (RCC) occurrence among 1036 RTX followed‐up from 1995 to July 2007. Abdominal ultrasonography was planned within 1‐month of transplant, then every 5 years, or 2 years if renal cysts developed. Based on presence and time of development of NRC, RTX were grouped into those with no (No‐NRC), new (New‐NRC), preexisting (Pre‐NRC) and time‐indeterminate NRC (TI‐NRC). Ten asymptomatic RTX were diagnosed with RCC at a median of 5.8 years posttransplant and had 5‐year graft and patient survivals of 90% and 100%, respectively, following appropriate therapy. RCC occurred only in Pre‐NRC and TI‐NRC who had significantly longer dialysis duration than No‐ or New‐NRC (6.7 ± 3.9 and 3.3 ± 3.2 vs. 2.7 ± 3.1 and 2.6 ± 2.4 years, respectively). These results suggest that NRC and increased dialysis duration are risk factors for RCC posttransplant. Since early treatment of RCC gives excellent outcomes, regular ultrasonography performed within a month of transplantation, then every 5 years for those without cysts and every 2 years for those with cysts for early detection of RCC is recommended.     

Von Hippel—Lindau病肾癌的临床特征分析

目的 探讨Von Hippel-Lindau（VHL）病肾癌的临床特点。方法回顾分析28例VHL病肾癌患者的临床资料。就初诊年龄、肿瘤部位、同时或异时癌、肿瘤的组织病理等与散发性肾癌进行比较。结果VHL肾癌初诊年龄44．6岁，双肾癌15例、多灶性肾癌16例、伴双侧多发肾囊肿20例。共切除87个实性肿瘤。术后病理：透明细胞癌86个，Fuhrman分级Ⅰ级73个、Ⅱ级12个、Ⅲ级1个；钙化结节1个。TNM分期ⅠA期、ⅠB期、Ⅱ期、Ⅲ期分别为8例、7例、8例和1例。与散发性肾癌组相比，VHL病肾癌组患者发病年龄早（P〈0．05），双肾多灶性肾癌及伴双侧多发肾囊肿比例高（P〈O．001），高级别肿瘤比例低（P〈O．05）。结论VHL病肾癌不同于散发性肾癌，有其独特的临床病理特征，这对该病诊断治疗具有一定指导价值。     

Bilateral multilocular cystic renal cell carcinoma]

A case of bilateral renal cell carcinoma with multilocular cysts is described. A 42-year-old female was admitted to our hospital for the purpose of further examination or right renal cystic mass discovered incidentally by ultrasonography. After she was examined by CT-scan and angiography, right nephrectomy was performed under the diagnosis of right renal cancer. Histological diagnosis was multilocular cystic renal cell carcinoma. One year later a small cystic legion was found in the left kidney. Under the diagnosis of left renal cancer, left partial nephrectomy was performed. Histological diagnosis was multilocular cystic renal cell carcinoma same as the right kidney. Multilocular renal cyst is classified into several classes by its style of development. This case of bilateral renal cell carcinoma which grew to be multilocular cysts is the first case in Japan as far as we can search.     

Evaluation of complicated renal cyst: a comparison of CT and MR imaging]

We report 12 cases of renal cystic lesions that could not be diagnosed preoperatively. Sonography, computed tomography (CT), magnetic resonance (MR) imaging, and angiography were performed in all cases. Angiography was not helpful in evaluating cystic lesions, because all cystic lesions were hypovascular or avascular within the cystic mass. CT was useful in depicting the fine structural abnormalities, and especially bolus-contrast CT study was useful in the differentiation of cystic renal cell carcinoma from simple renal cyst. However, there were 5 false positive cases. MR imaging is superior to CT in distinguishing a hemorrhagic cyst or multiloculated cystic mass. In conclusion, CT is currently the primary imaging modality for evaluating complicated renal cysts, and surgical exploration is warranted for the undiagnosed cystic lesion by CT. However, MR imaging also has an important role in detecting the benign complicated cyst. Therefore if complicated cyst is thought to be benign by MR imaging, parenchyma-sparing surgery should be considered preoperatively.     

Surgical exploration for renal cyst: two-case report]

A 59-year-old male was admitted to our clinic for further examination of the calcified renal cyst discovered incidentally on medical workup elsewhere. CT showed a left renal cyst associated with calcification. Ultrasound-guided puncture of the renal cyst was not successful because of thickness of the cystic wall. Renal angiography showed hypervascularity of the cystic wall. Association of renal cell carcinoma could not be ruled out, therefore the exploration was performed. Histological examination revealed benign renal cyst with calcification. A 27-year-old male presented with the chief complaint of left flank pain. Following examinations by US, CT and MRI, a renal cyst associated with renal cell carcinoma was highly suspected. Subsequent exploration revealed cluster of cysts with a yellowish lesion a few mm in diameter. Frozen section revealed no malignancy, and cystic fluid was not hemorrhagic. Therefore as many cystic walls as possible were removed without nephrectomy. Histological examination of the permanent specimen revealed renal cell carcinoma. Renal cyst associated with renal cell carcinoma was regarded as rare clinical entity, but such cases are reported in increasing number in recent years. We report such cases and review the pertinent literature in this paper.