Juxtaglomerular cell tumor: Clinical and immunohistochemical features

Molecular Characterization of Juxtaglomerular Cell Tumors: Evidence of Alterations in MAPK-RAS Pathway

Juxtaglomerular cell tumor (JGCT) is a rare neoplasm, part of the family of mesenchymal tumors of the kidney. Although the pathophysiological and clinical correlates of JGCT are well known, as these tumors are an important cause of early-onset arterial hypertension refractory to medical treatment, their molecular background is unknown, with only few small studies investigating their karyotype. Herein we describe a multi-institutional cohort of JGCTs diagnosed by experienced genitourinary pathologists, evaluating clinical presentation and outcome, morphologic diversity, and, importantly, the molecular features. Ten JGCTs were collected from 9 institutions, studied by immunohistochemistry, and submitted to whole exome sequencing. Our findings highlight the morphologic heterogeneity of JGCT, which can mimic several kidney tumor entities. Three cases showed concerning histologic features, but the patient course was unremarkable, which suggests that morphologic evaluation alone cannot reliably predict the clinical behavior. Gain-of-function variants in RAS GTPases were detected in JGCTs, with no evidence of additional recurrent genomic alterations. In conclusion, we present the largest series of JGCT characterized by whole exome sequencing, highlighting the putative role of the MAPK-RAS pathway.

Clinical features, laboratory findings and treatment of juxtaglomerular cell tumors: a systemic review

Juxtaglomerular cell tumors (JGCTs) or reninoma are rare kidney tumors leading to secondary hypertension, and the non-specific clinical manifestations bring about challenges to the diagnosis. This study is to summarize the clinical features, laboratory findings, and treatment of JGCTs. The PubMed, EMBASE database, and manual search were utilized to find all cases, and 158 reports containing 261 patients were identified. Data on patients' demographics, clinical features, diagnostic methods, and treatment options were collected and analyzed. JGCTs occurred predominantly in female patients (female to male ratio, 2.1:1). The median age of patients was 25 years (IQR:18-34 years). Hypertension (97.24%) was the cardinal manifestation. Hypokalemia was reported in 78.71% (159/202) of subjects, and normal serum potassium accounted for 20.79% (42/202). In cases with assessed plasma renin activity (PRA) levels, the median PRA was 7.89 times the upper limit of normal (IQR:3.58-14.41), and 3.82% (5/131) of cases in the normal range. Tumors were detected in 97.8% (175/179) computed tomography (CT), 94.7% (72/76) magnetic resonance imaging (MRI), and 81.5% (110/135) ultrasound, respectively. For 250/261 patients undergoing surgical procedures, 89.14% (197/221), 94.94% (150/158), and 100% (131/131) of patients were restored to normal blood pressure, PRA, and serum potassium, respectively. JGCTs are commonly associated with hypertension, hypokalemia, and hyperreninemia, whereas patients with normotension, normokalemia, and PRA should be systematically pursued after drug-elution lasting for 2 weeks. CT and MRI are more sensitive imaging diagnostic methods. The blood pressure and biochemical parameters of most patients returned to normal after surgery.

Juxtaglomerular cell tumor: report of a case with unusual presentation

Juxtaglomerular cell tumor is a benign, renin-secreting neoplasm. The tumor arises from the juxtaglomerular apparatus cells of the kidney. Because the tumor is hormonally active, patients usually suffer from hypokalemia, hyperaldosteronism, and hypertension. Herein, we describe a case of a 19-year-old Asian female with a somewhat unusual presentation.

A 19-year-old Asian female presented with upper extremity weakness, numbness, and tingling. On physical examination, the only notable finding was hypertension. Extensive workup revealed elevated aldosterone level and plasma renin activity. CT scan of the abdomen revealed a 2.2 cm mass in the lower pole of the left kidney. The mass was resected by partial nephrectomy. On microscopic evaluation, the tumor had glomoid appearance with sheets of uniform, round to polygonal cells with clear to eosinophilic cytoplasm. Immunohistochemical stains showed the tumor cells to be positive for CD117, CD34 and CD10 and negative for ER, PR, CK7, PAX-8, pan-cytokeratin, EMA, S100, Melan-A, HMB45, SMA and CAIX. Diagnosis of Juxtaglomerular cell tumor was rendered. This case highlights the importance of a regular physical exam and a high index of suspicion in patients presenting with unusual complaints.

Juxtaglomerular cell tumour of the kidney: a rare cause of resistant hypertension

SUMMARY

Juxtaglomerular cell tumour (JGCT) is an unusually encountered clinical entity. A 33-year-old man with severe long-standing hypertension and hypokalaemia is described. The patient also suffered from polyuria, polydipsia, nocturia and severe headaches. On admission, laboratory investigation revealed hypokalaemia, kaliuresis, high aldosterone and renin levels, and the abdomen CT identified a mass of 4 cm at the right kidney. Kidney function was normal. Following nephrectomy, the histological investigation revealed the presence of a JGCT. Immunostaining was positive for CD34 as well as for smooth muscle actin and vimentin. Following surgery, a marked control of his hypertension with calcium channel blockers and normalization of the serum potassium, renin or aldosterone levels were reached. According to our findings, JGCT could be included in the differential diagnosis of secondary hypertension as it consists of a curable cause. The association of JGCT with hypertension and hypokalaemia focusing on the clinical presentation, diagnostic evaluation and management is herein discussed and a brief review of the existing literature is provided.

LEARNING POINTS

Juxtaglomerular cell tumours (JGCT), despite their rarity, should be included in the differential diagnosis of secondary hypertension as they consist of a curable cause of hypertension. JGCT could be presented with resistant hypertension along with hypokalaemia, kaliuresis and metabolic alkalosis. Early recognition and management can help to prevent cardiovascular complications. Imaging (enhanced CT scans) may be considered as the primary diagnostic tool for the detection of renal or JGCT. For the confirmation of the diagnosis, a histopathologic examination is needed.

Spindle Cell Hemangioma and Atypically Localized Juxtaglomerular Cell Tumor in a Patient with Hereditary BRIP1 Mutation: A Case Report

Spindle cell hemangioma is a benign vascular tumor typically occurring in the dermis or subcutis of distal extremities as red-brown lesions that can grow in both size and number over time. They can be very painful and potentially disabling. A family history of cancer or previous history may be relevant and must be taken into consideration. Juxtaglomerular cell tumor (reninoma) is an extremely rare cause of secondary hypertension diagnosed mostly among adolescents and young adults. Excessive renin secretion results in secondary hyperaldosteronism. Subsequent hypokalemia and metabolic alkalosis, together with high blood pressure, are clues for clinical diagnosis. Histological examination of the excised tumor leads to a definitive diagnosis. Reninoma is found in subcapsular localization, in most cases as a solitary mass, in imaging studies of kidneys. Exceptionally, it can be located in another part of a kidney. Both spindle cell hemangioma and reninoma are extremely rare tumors in children and adolescents. Herein, the authors present a case report of a patient with hereditary BRCA1 interacting protein C-terminal helicase 1 (BRIP1) mutation, spindle cell hemangioma, and secondary hypertension caused by atypically localized reninoma.

The Small Size and Superficial Location Suggest That Laparoscopic Partial Nephrectomy Is the First Choice for the Treatment of Juxtaglomerular Cell Tumors

BACKGROUND

Juxtaglomerular cell tumor (JGCT) is a very rare disease, and surgical resection is the only possible way to cure this tumor. Open nephrectomy and partial nephrectomy have been reported to manage JGCTs with excellent results in the previous reviews. Laparoscopic surgery has been popularized in recent years, while critical issues associated with laparoscopic surgical management have been seldom reported. We summarized the JGCTs in our center to discover the optimal surgical management and its anatomic foundation.

METHODS

In this retrospective study, we enrolled a total of 14 JGCT patients. All patients received surgeries and were followed up for up to 11 years. We mainly summarized the size and location of tumors, imaging features, and surgical strategies. A descriptive statistical analysis was performed.

RESULTS

The JGCTs in this study had a median size of 1.35 cm and all located superficially, mainly in the cortical or subcortical area of the kidney. All 14 patients had hypertension, ten had hypokalemia, and seven had elevated plasma renin activity. Pathologically, JGCT cells were polygonal or spindle shape, with positive CD34 and vimentin immunostaining. All patients received partial nephrectomy; nine were laparoscopic, and five were open. Laparoscopic partial nephrectomy (LPN) was performed in seven out of eight patients over the last nine years. Postoperative blood pressure, serum potassium, and plasma renin activity were normal in all patients. No recurrence occurred within a median follow-up of 60 months.

CONCLUSION

The small size and superficial location are the characteristic anatomic features of JGCT; they suggest that LPN is the preferred surgical strategy. Laparoscopic ultrasound is helpful for the intraoperative detection of small JGCTs. Longer follow-up is required to examine the biological behavior of JGCTs and the effect of LPN.

Case report: a nonfunctioning juxtaglomerular cell tumor mimicking renal cell carcinoma

INTRODUCTION

Based on existing literature, the juxtaglomerular cell tumor (JGCT) is a rare renal tumor, typically present with hypertension and hypokalemia. Nonfunctioning JGCT, without hypertension or hypokalemia, is extremely rare.

PATIENT CONCERNS

Herein, we report a case of nonfunctioning JGCT mimicking renal cell carcinoma. The 29-year-old woman with an unremarkable past medical history presented with a left renal tumor without hypertension or hypokalemia.

DIAGNOSIS

Both CT and 18F-FDG-PET/CT suggested a malignancy, possibly renal cell carcinoma.

INTERVENTIONS

The tumor was then removed completely via robotic assistant laparoscopic partial nephrectomy; and pathology result was JGCT. Since the patient had no hypertension or hypokalemia, a nonfunctional JGCT was diagnosed.

OUTCOMES

The patient recovered uneventfully, and was in good health in 6-months' follow-up period.

CONCLUSION

Preoperative identification of JGCT is very difficult due to the lack of specific clinical manifestations. This case teaches us that for young patients with renal tumors whose CT enhancement is not obvious at the early phase, JGCT should be considered as a differential diagnosis. Radical nephrectomy should be avoided for JGCT in consideration of its relatively good prognosis.

Juxtaglomerular cell tumor: Clinicopathologic evaluation in a large series emphasizing its broad histologic spectrum

The juxtaglomerular cell tumor (JCT) is a rare renal tumor. We re-evaluated the clinicopathologic features of 21 JCTs to summarize their variable morphologies. Immunohistochemical, fluorescent in situ hybridization and periodic acid-Schiff stains were routinely performed, and four JCT cases were detected via transmission electron microscopy. The 21 JCTs involved five males and 16 females, ranging in age from 19 years to 69 years (mean, 36.9 years; median, 34 years). The tumors were composed of large, small, or spindle cells with a round, oval or polygonal shape, arranged in various growth patterns. Both necrosis (1/21) and mitosis (2/21, with 1/50HFP, 8/50HFP) was rarely appreciated. All cases were immunoreactive for renin and CD34 (21/21), and few were positive for α-SMA (13/21;11/21, focally; 2/21, diffusely,), CD117 (9/21, focally) and synaptophysin (3/21, focally). Ultrastructurally, all four cases exhibited secretory granules in varying sizes in the cytoplasm, two of which exhibited cellular junctions. Almost all cases (20/21) had a favorable prognosis, but one succumbed due to bone and hepatic metastases, which corresponds to malignant JCT. Our study demonstrates that JCTs may have atypical clinical presentations and variable histologic appearances. A familiarity with these features may contribute to a correct diagnosis.

Characterization and Management of Juxtaglomerular Cell Tumor: Analysis of 9 Cases and Literature Review

Aims:

Juxtaglomerular cell tumor is a rare kidney tumor. This study aimed to report the clinic features of juxtaglomerular cell tumor and our treatment experience.

Methods:

The medical records of 9 juxtaglomerular cell tumor patients treated in our hospital from 1997 to 2017 were retrospectively reviewed. Clinical characteristics, immunohistochemical findings, treatments and outcomes were collected.

Results:

The mean age of 9 patients was 24±8.1 years (range: 18-37). All cases had symptoms of hypertension, hyperaldosteronism, high plasma renin, high plasma angiotensin II. Four cases had hypokalemia. The renal masses were found by enhanced contrast tomography in all patients. One case received ultrasound-guided ablation and was clinically diagnosed with juxtaglomerular cell tumor. Among the remaining 8 cases, 2 cases received nephrectomy while 6 underwent partial nephrectomy. The 8 cases were pathologically diagnosed with juxtaglomerular cell tumor. Immunohistochemical findings showed that juxtaglomerular cell tumor was positive for vimentin, CD34, and actin but negative for chromogranin A. After treatment, all the patients had normal levels of blood pressure, serum renin activity, potassium, and aldosterone. No patients had tumor progress or metastasis within a median follow-up period of 94 (range: 33-241) months.

Conclusion:

Hypertension combined with hyperaldosteronism and hypokalemia secondary to high plasma renin activity are the typical symptoms of juxtaglomerular cell tumor. Partial nephrectomy is an optimal treatment for juxtaglomerular cell tumor.

Juxtaglomerular Cell Tumor With Atypical Pathological Features: Report of a Case and Review of Literature

Juxtaglomerular cell tumor (JGCT) is a rare renal tumor with a predominantly benign clinical course. It affects young adults, who often present with hypertension, hypokalemia, and hyperaldosteronism. The tumor cells are round to spindle-shaped with occasional mild to moderate atypia, but mitotic figures are usually absent. Surgical resection is the treatment of choice. Typically, the blood pressure and renin levels normalize after removal of the tumor. Rare cases of metastatic and recurrent JGCT have been reported including cases with vascular invasion. These cases typically occur in older adults and present with larger tumor size (9-15 cm). We report a case of JGCT, 5.5 cm in greatest dimension, with atypical pathological features including invasion of the renal vein, lymphovascular invasion, and significant pleomorphism with rhabdoid morphology, along with a brief review of the literature.

Case Report of Atypical Juxtaglomerular Cell Tumor

Juxtaglomerular cell tumor (JGCT) is a rare renal tumor, producing renin and behaving almost in a benign fashion. So far, only three cases have been reported as malignant. We report a rare case with atypical JGCT. A 74-year-old male was referred to our hospital due to hypertension, proteinuria, and hematuria. Abdominal CT revealed a mass measured in 9.7×7.0 cm in the lower portion of the right kidney. Right kidney was removed laparoscopically. Grossly, white to tan tumor with massive hemorrhage and necrosis occupied the lower portion of the right kidney. Microscopically, tumor grew in a solid fashion. Tumor cells were polygonal to ovoid cells with round nuclei and clear to eosinophilic cytoplasm. Mitosis was found in 5 per 10 HPF. Immunohistochemically, tumor cells were stained by vimentin and CD34. Some tumor cells were also positive for renin. Electron micrograph showed near rhomboid crystalline structure in the tumor cells. Because of massive necrosis and mitotic figures, diagnosis of atypical (potentially malignant) JGCT was rendered. Gene mutations for IDH1, PIK3CA, K-ras, N-ras, Braf, and EGFR were not found by MBP-QP system.