Multilocular cystic renal cell carcinoma: report of a case

We report a case of multilocular cystic renal cell carcinoma seen in a 54-year-old man. At the annual health check he was found to have numerous cysts of various sizes in the lower pole of the left kidney. Plain CT scan disclosed a mass in the lower pole of the left kidney. On enhanced CT scan septa were visible, suggesting a multilocular cyst. Left renal arteriography disclosed a hypervascular mass in the lower pole of the left kidney. Radical nephrectomy was performed. The gross appearance of the cut surface showed a feature of multilocular cyst. The histopathological diagnosis was clear cell carcinoma. We describe the clinical features of multilocular cystic renal cell carcinoma and discuss the differential diagnosis.     

A case of renal leiomyoma with extensive cystic degeneration

An extremely rare case of renal leiomyoma presenting as a cystic mass, involving the upper pole of the right kidney in a 59-year-old woman, complaining of right flank pain is reported. Some discussion regarding pathogenesis of leiomyoma with cystic change, diagnostic feature, malignant potential of leiomyoma and others was done. Since 1948, 19 cases including our own case of renal leiomyoma have been reported in the Japanese literature.     

Two cases of renal cell carcinoma accompanied with ossification]

We report two cases of renal cell carcinoma accompanied with ossification. Case 1: A 40-year-old male visited a physician with the complaint of epigastric pain. Examination of the stomach revealed compression of the greater curvature. Abdominal radiography and CT scan revealed a left renal mass with calcification, which was a hypovascular tumor on angiography. A transperitoneal left nephrectomy was performed. The resected kidney was 700g in weight and the tumor, which was 12 x 10 x 10 cm in size and located in the upper pole of the kidney, was enveloped with a hard capsule and was extensively necrotized. Histopathological diagnosis was renal cell carcinoma (papillary type, mixed subtype). Case 2: A 69-year-old female was occasionally pointed out to have a left renal mass in ultrasonic examination. It was accompanied with calcification in CT scan and a hypervascular tumor in angiography. A transperitoneal left nephrectomy was performed. The resected kidney was 320 g in weight and the tumor located in the lower pole of the kidney, was 6 x 6 x 6 cm in size and necrotized. Histopathological diagnosis was renal cell carcinoma (alveolar type, clear cell subtype). Microscopically in both cases, ossified tissue existed among the fibrous tissue in the necrotized lesion of the tumor, but not near the cancer cells and, it was accompanied by calcification. During the ossification process, the connective tissue proliferates after the necrosis of the tumor, and metaplasia occurred from its juvenile plastic cells to osteoblastic cells.     

Leiomyoma of the kidney: presentation of 4 new cases and the role of computerized tomography

Renal leiomyoma is a challenging diagnostic and therapeutic condition. It is clinically similar in presentation and radiographic appearance to its malignant counterpart, leiomyosarcoma. We review 30 cases of clinically diagnosed leiomyoma of the kidney from the literature, including 4 new cases with emphasis on the computerized tomography findings. Computerized tomography may locate a renal leiomyoma serendipitously in an asymptomatic patient. If the lesion is peripheral or in the parapelvic area and a plane can be seen between the tumor and kidney a capsular tumor, such as a leiomyoma of the kidney, might be considered in addition to the more common renal cell carcinoma. Renal leiomyomas have a variable radiographic pattern from that of a pure cystic to a mixed solid/cystic to an entirely solid lesion. Renal leiomyomas usually are sharply demarcated from the surroundings. Although computerized tomography cannot distinguish a renal leiomyoma from other benign or malignant renal processes the presence of invasion can virtually eliminate this benign tumor as a diagnosis. Since a preoperative diagnosis cannot be made, management involves renal exploration and radical nephrectomy in the larger lesions with a renal-sparing operation possible in selected cases. After treatment patients have a uniformly excellent prognosis.     

原发性肾脏类癌2例报告并文献复习

目的：探讨原发性肾脏类癌的临床特征及诊治方法。方法：总结2例原发性肾脏类癌患者的临床资料结合文献复习讨论。例1,女,48岁。因右腰酸痛1个月入院。B超示右肾中上极中等回声占位,边界清楚,内有血流信号。CT示右肾中上极10．0cm×7．5cm实性占位,增强后病灶均匀轻度强化。例2,男,44岁。体检发现左肾占岱40天入院。B超示左肾门处中等回声占位,边界清楚,内有血流信号。CT示左肾中极肾门处3．7cm×3．5cm实性占位,增强后病灶均匀轻度强化;其内伴-钙化点。结果：2例均行根治性肾切除术。病理检查镜下肿瘤细胞形态为多边形,嗜酸性颗粒状细胞质,边界不清,呈柱状或缎带状排列混合有实性巢状排列;细胞核呈园形大小一致,核分裂像难见。免疫组化：突触素、波形蛋白均为阳性。病理诊断为肾脏类癌伴淋巴结转移。例1术后30个月死于肝骨转移;例2术后随访26个月,未见肿瘤复发转移。结论：原发性肾脏类癌临床罕见,易发生淋巴结转移,确诊依靠病理学检查,根治性肾切除应为治疗原发性肾类癌的首选方法。     

A case of renal cell carcinoma difficult to diagnose preoperatively because of hypovascular findings

A 35-year-old man visited our out-patient clinic with the chief complaint of macroscopic hematuria. After admission to the hospital, examinations by CT scan, renal angiography, etc. revealed a hypovascular space-occupying lesion in the right kidney, but no definite diagnosis could be made; blood findings such as accentuated alpha 2-globulin and raised LDH suggested the possibility of malignancy; and right nephrectomy was performed. In view of the preoperative X-ray findings together with postoperative pathological findings, papillary renal cell carcinoma was suspected intensively. Some discussion was made on the differentiation of lesions of hypovascular to avascular tumors and the reliability of image diagnosis based on CT scan, angiography, and other methods.     

Renal oncocytoma with cystic degeneration: a case report

A 45-year-old man was referred to our department because of a right renal mass which was incidentally found at a health screening. Ultrasound sonography, computerized tomography and magnetic resonance imaging showed a hypovascular tumor 3 cm in diameter with the fluid at the upper pole of the right kidney, implicating that the tumor was renal cell carcinoma originating from a renal cyst wall, or with central necrosis. A radical nephrectomy was therefore performed. The tumor was dark-brown and contained brown fluid. The histopathological findings showed renal oncocytoma with cystic degeneration.     

Adult Wilms' tumor: a case report

We present a case report of adult Wilms' tumor and reviewed from 1981. A 22-year-old woman with chief complaints of gross hematuria and right backache was introduced to our hospital in March 1998. Abdominal computed tomography (CT) revealed a solitary irregular mass (5.0 cm) at the lower pole of right kidney with no contrast medium enhancement. Angiography showed a hypovascular character, but irregular vascularization was found in the tumor. We performed a radical nephrectomy with a preoperative diagnosis of malignant renal tumor. Finally, adult Wilms' tumor (epithelial type) was diagnosed by pathological examination. We retrospectively studied the clinical and radiological features in 16 reported cases of adult Wilms' tumor from 1981. The average age was distinctly younger than that of renal cell carcinoma. Nearly half of the cases were at an advanced clinical stage (direct invasion or metastasis to other organs) at first consultation. Radiologically, Wilms' tumor tends to be visualized as a low density mass in the precontrast CT scan (75.0%) and hypovascular tumor by selective angiography (84.6%). Although this is not a definitive character to distinguish adult Wilms' tumor from renal cell carcinoma, it may be useful information for differential diagnosis.     

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.     

Chromophobe cell renal carcinoma: report of two cases

We report two cases of chromophobe cell renal carcinoma. Case 1 was in a 62-year-old man with the chief complaint of hematospermia. Ultrasound incidentally detected a left renal mass. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a relatively homogeneous, hypovascular tumor of the left kidney. We performed radical nephrectomy after making a clinical diagnosis of possible renal carcinoma. Case 2 was in a 66-year-old woman who was admitted to our hospital after a left renal mass was incidentally found by ultrasonography during a health check. We performed laparoscopic radical nephrectomy after making a diagnosis of renal cell carcinoma by CT and MRI. Both of the tumors were shown to be chromophobe cell carcinoma by microscopic examination after H & E staining and immunohistochemistry using Hale's colloidal iron stain. Chromophobe cell carcinoma is an uncommon type of renal cell carcinoma and the number of reported cases is limited in Japan. The clinical features and management of this rare tumor are discussed.     

A report of two cases of multilocular cystic renal cell carcinoma: review of 51 cases reported and the results of a prognostic survey]

We report 2 cases of multilocular cystic renal cell carcinoma. One was in a 33-year-old male, presenting with ultrasonic abnormality of the left kidney at an annual employee health care examination. Computerized tomography (CT) demonstrated a 5 cm of multilocular cystic mass adjacent to the lower pole of the left kidney. Another was in a 44-year-old male, presenting with microscopic hematuria at an annual employee health care examination. CT of the abdomen revealed a 6.5 cm of multilocular cystic mass on the upper pole of the right kidney. Both were diagnosed as renal cell carcinoma by the angiography and underwent radical nephrectomy. Gross specimens showed typical multilocular cystic appearance and histopathology showed clear cell carcinoma infiltrating septa and replacing epithelium of the cyst walls. Both patients are alive without evidence of disease at, 21 months and 14 months after operation, respectively. Including our cases, 51 multilocular cystic renal cell carcinoma and multilocular cystic nephroma associated with renal cell carcinoma have been reported. From the review of the literatures and the answer of the questionnaires inquiring about the outcome of the patient to Japanese reporters, the outcome of 38 patients was ascertained. The 10-year survival rates and non-recurrence rate after operation calculated by the Kaphan-Meier formula were 97.3% and 90.3%, respectively. Because of the good prognosis of reported cases, we concluded that we should choose kidney-sparing surgery for the operation of multilocular cystic renal cell carcinoma.     

后肾腺瘤的CT影像特征（附1例报告并文献复习）

目的提高对后肾腺瘤的影像诊断水平。方法回顾性分析1例后肾腺瘤患者的临床资料,术前CT检查诊断为左肾嫌色细胞癌,行腹腔镜下左肾部分切除术,术后病理确诊为后肾腺瘤。结果 CT提示左肾下极实性肿物,平扫期肿物边界不清,内部密度不均,稍低于邻近肾实质密度,伴有坏死灶和点状钙化,增强扫描肿块呈不均匀轻度强化,双期增强扫描呈渐进性强化,强化程度始终明显低于邻近正常肾实质。术后病理确诊为后肾腺瘤。术后患者恢复良好,随访8个月,未见肿瘤复发。结论后肾腺瘤是罕见的肾上皮源性肿瘤,其CT影像表现有一定特异性,但与其他乏血供肾肿瘤难以鉴别,特别是肾嫌色细胞癌和乳头状肾细胞癌。术前的准确诊断对选择合适的临床治疗策略十分重要,可行术前或术中的病理检查鉴别。     

Simultaneous occurrence of renal cell and transitional cell carcinoma in the same kidney and ureter. A case report

An unusual case of 2 concurrent primary renal tumors within the same kidney is reported. A 70-year-old woman presented with gross hematuria when she was in the hospital for cerebral infarction. Excretory urography revealed a marked expansion of the right kidney with no renal function. CT scan showed a mass arising from the right kidney, the hydronephrotic right renal pelvis, and a mass in the lower right ureter. Selective renal angiogram showed marked neovascularity of the mass. There was an encasement of the intrarenal artery to the lower pole. Angiographic findings were highly suggestive of a renal cell carcinoma with a second neoplasm in the renal pelvis. Subsequently, the patient underwent right radical nephroureterectomy and partial cystectomy. Section of the removed specimen revealed a 4.0 X 3.8 cm solid tumor confined to the kidney in the upper pole and a transitional cell carcinoma arising from the renal pelvis. In addition, transitional cell carcinoma was present in the distal ureter.     

Diagnosis and treatment of renal angiomyolipoma

We have hitherto reported 6 cases of renal angiomyolipoma. Recently, we encountered two more such cases. Case 1 is a 34-year-old woman with fever as the chief complaint. DIP revealed a tumor mass in the right upper pelvic pole. This mass showed a strong echo level on ECHO and adipose tissue of low density on CT scan. Therefore, the patient was diagnosed as having renal angiomyolipoma. Since liposarcoma was not ruled out by the examination of frozen sections during operation, nephrectomy was performed. Case 2 is a 40-year-old woman. Diagnosed as having bilateral renal angiomyolipoma, she underwent right nephrectomy 14 years ago. Two years ago, she had heavy hematuria, and had embolization of the left renal artery. She has had no bleeding since the embolization. We are of the view that ECHO and CT can are very useful for diagnosis of renal angiomyolipoma, and embolization for heavy hematuria, a complication, should be performed first of all.     

A case of ruptured renal artery aneurysm treated effectively by endovascular embolization

Previously, renal arterial aneurysms were thought to be extremely uncommon. However, these lesions are now being detected more frequently as incidental findings on computed tomography (CT) and magnetic resonance imaging (MRI). The incidence of ruptured renal artery aneurysms is very low. A 58-year-old man presented to a physician complaining of left flank pain and was diagnosed as having a left kidney stone. Abdominal CT scan demonstrated a mass in the left renal pelvis. The mass measured 40mm in diameter and showed calcification. The patient was referred to our hospital 5 days after the first attack. Left renal mass was diagnosed as renal aneurysm based on clinical signs and perirenal findings on CT. Emergent endvascular embolization was performed. The postoperative course was uneventful. Hypertension improved after embolization.     

Renal leiomyoma: Case report and literature review

Renal leiomyomas are rare benign tumours of the kidney originating from muscle cells. They are usually found by an autopsy, whether the patient is asymptomatic or has symptoms (i.e., abdominal/flank pain, hematuria, palpable mass). Today the widespread use of ultrasonography and computed tomography has increased the detection of clinically asymptomatic renal leiomyomas. The differential diagnosis between leiomyomas and other malignant lesions (above all renal cell carcinoma or leiomyosarcoma) is still possible by histological examination. Radiological examinations are not sufficient for the differential diagnosis. Renal leiomyomas have no aggressive behaviour and they usually do not metastasize. The prognosis, after surgery, is excellent without recurrence. We report a case of leiomyoma in a 31-year-old man who presented hematuria and flank pain. We also review the literature and provide a summary of clinical, radiological and histological features of renal leiomyomas.     

Two cases of retroperitoneal functioning paraganglioma

We report two cases of retroperitoneal functioning paraganglioma. Case 1: A 52-year-old male patient was admitted to our hospital for further examination of pulsating abdominal pain with chest pain and headache. Overfist-size smooth-surfaced hard mass was palpated at the right upper abdominal quadrant. Catecholamine levels in serum and urine showed marked elevation. Computed tomographic (CT) scan, magnetic resonance imaging (MRI) and angiography revealed a large tumor between the right kidney and aorta. He underwent surgical removal of the tumor and histological examination revealed paraganglioma. His chief complaints disappeared postoperatively. Case 2: A 68-year-old female patient was admitted to our hospital for control of diabetes. An abnormal mass was shown ultrasonically at the left renal region by routine screening examination. A marked increase of noradrenaline in serum and urine was observed. Abdominal CT scan, MRI and angiography revealed a retroperitoneal tumor which was located adjoining to the lower pole of the left kidney. The tumor was removed transabdominally. Histopathological studies showed paraganglioma. After the operation her blood sugar and noradrenaline levels decreased to the normal range.     

A case report of extensively calcified renal cell carcinoma

A 73-year-old woman visited another hospital with complaints of occasional episodes of gross hematuria. A computed tomographic (CT) scan revealed extensive calcification in the left kidney, and she was referred to our hospital for further examinations. The physical examination was unremarkable other than mild back pain on her left side. Blood chemistry was normal. The CT scan revealed a mildly enhanced tumor of 6 cm in diameter accompanied by extensive calcification in the left kidney. Angiography revealed a hypovascular tumor in the left kidney. A left radical nephrectomy was carried out. Gross appearance of the specimen showed extensive calcification from the renal pelvic to the parenchyma of the lower pole of the left kidney. The histopathological diagnosis was renal cell carcinoma, alveolar type, mixed subtype, pT2pN0pM0.     

Two cases of renal oncocytoma

Two cases of renal oncocytoma are reported. These patients were a 67-year-old man and a 74-year-old man who had incidentally been indicated to have a right renal mass lesion by echography in other hospitals. In both cases, enhanced computed tomographic scan showed a low density renal mass. In selective renal angiogram of the two cases, a spoke-wheel configuration of vessels could be seen in one case, but there was no evidence of renal mass in another. Total nephrectomy was performed in each case. Two masses were pathologically diagnosed as oncocytoma, constructed of large eosinophilic cells with granular cytoplasm and small regular nuclei. These two patients have been well for more than 2 years after the surgery. These are the 25th and 26th cases of renal oncocytoma reported in Japan before December, 1988.     

Lymphangioma of the kidney

Lymphangiomas are rare benign tumors that are congenital malformations of the lymphatic system. Most cases present in children as a soft, cystic mass in the neck and the axilla. Primary renal lymphangioma is exceedingly rare, with only 35 cases reported so far. We report a case of primary lymphangioma arising from the kidney. A 59-year-old man was referred for evaluation of a right renal mass found in an abdominal ultrasonography during a health checkup. Abdominal ultrasonography and computed tomography (CT) revealed a 3.2 x 2.9 cm multiloculated cystic mass in the upper pole of the right kidney. We could not deny malignant disease such as cystic renal cell carcinoma with any diagnostic modalities. The patient was brought to surgery. During the surgical procedure, the tumor was suspected to be lymphangioma of the kidney as a result of a frozen- section histopathological evaluation. Therefore enucleation of the tumor was performed. Pathological evaluation of the specimen revealed lymphangioma arising from the kidney. The patient is free of disease after a 3-month follow-up period.