Giant renal oncocytoma: a case report and review of the literature

A Giant Oncocytoma in an Elderly Female Patient: A Case Report

Renal oncocytomas are rare, benign tumors that can be difficult to distinguish from malignant renal cell carcinomas. This case report presents an 84-year-old woman with a sizeable renal oncocytoma and discusses this rare entity's diagnostic challenges and management.

Giant asymptomatic left renal oncocytoma in a 40-year-old man: a case report

Renal oncocytoma is a benign tumor that arises from epithelial cells of the distal renal tubules. It is naturally presented with a small-sized mass, and giant oncocytoma is uncommon. Renal oncocytoma is frequently asymptomatic and challenging to distinguish preoperatively from renal cell carcinoma (RCC). We present a 40-year-old man who presented with intermittent abdominal pain in the last two years. Abdominal computed tomography (CT) scan showed a large, heterogenous left renal mass measured 15 x 16 x 19.5 cm and associated with central calcifications suspected of RCC. The patient underwent a left radical nephrectomy without complication. The histopathological study revealed typical oncocytoma features. There was no detected recurrence or distant metastasis on six months follow-up. In conclusion, it is challenging to distinguish renal oncocytoma from RCC via preoperative radiology images, especially when a giant mass is present. The only histopathology examination of the removed specimen can provide a definitive diagnosis.

High-Resolution Ultrasonography of Renal Oncocytoma Presenting with Symptomatic Hematuria and Urinary Bladder Clot Retention-A Rare Occurrence

Renal oncocytomas are asymptomatic, benign tumors often encountered incidentally on various imaging modalities. Renal oncocytomas comprise 5–7% of primary renal neoplasms and are derived from cells of the distal renal tubule. We present a case report of renal oncocytoma in a 22-year-old male having right-sided flank pain and symptomatic gross hematuria with a giant urinary bladder clot retention. The tumor was excised, and the patient underwent laparoscopic partial nephrectomy. Typical features of renal oncocytoma were observed upon histopathological examination of the resected specimen. The patient was catheterized, and bladder irrigation with clot retraction was performed.

Symptomatic giant renal oncocytoma with an incidental papillary adenoma

Renal oncocytomas are benign, slow-growing tumours accounting for 3-7% of all solid renal neoplasms. These tumours tend to be small, unilateral and asymptomatic and are often discovered incidentally on imaging. Large oncocytomas are rare and can be difficult to distinguish from renal cell carcinoma based off clinical findings or imaging characteristics alone. Papillary adenomas are also benign renal neoplasms but arising from the renal tubular epithelium and almost always located within the cortex. We present a case of a 63-year-old Caucasian male with a large symptomatic renal oncocytoma with an incidental concurrent papillary adenoma.

Oncocytoma: A Differential Consideration for an Incidentally Detected FDG-Avid Renal Mass on PET/CT

Renal oncocytoma is a benign renal neoplasm that is often discovered incidentally and closely mimics renal cell carcinoma on common imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI). Due to the inability to reliably distinguish between these benign and malignant lesions with imaging, both are typically treated as if they are malignant. Hypermetabolic activity of renal oncocytomas is not frequently encountered because positron emission tomography (PET) is not a standard modality for imaging primary renal tumors. We present a case of a 65 year-old female with a history of thyroid cancer who had an incidentally discovered hypermetabolic renal mass on surveillance PET-CT imaging. Due to the concern for a primary renal malignancy or metastatic disease, the mass was resected and proven to be an oncocytoma on pathologic review.

Differentiation of oncocytoma from chromophobe renal cell carcinoma (RCC): can novel molecular biomarkers help solve an old problem?

Standard treatment of renal neoplasms remains surgical resection, and nephrectomy for localised renal cell carcinoma (RCC) still has the best chance of cure with excellent long-term results. For smaller renal masses, especially stage T1a tumours less than 4 cm, nephron-sparing surgery is often employed. However, small incidentally detected renal masses pose an important diagnostic dilemma as a proportion of them may be benign and could be managed conservatively. Renal oncocytoma is one such lesion that may pose little risk to a patient if managed with routine surveillance rather than surgery. Additionally, lower-risk RCC, such as small chromophobe RCC, may be managed in a similar way, although with more caution than the renal oncocytomas (RO). The ability to differentiate ROs from chromophobe RCCs, and from other RCCs with a greater chance of metastasis, would guide the physician and patient towards the most appropriate management, whether nephron-sparing surgical resection or conservative surveillance. Consistent accurate diagnosis of ROs is likely to remain elusive until modern molecular biomarkers are identified and applied routinely. This review focuses on the differentiation of renal oncocytomas and chromophobe RCCs. It summarises the history, epidemiology and clinical presentation of the renal neoplasms, explains the diagnostic dilemma, and describes the value, or not, of current molecular markers that are in development to assist in diagnosis of the renal neoplasms.

[Renal oncocytoma in pregnancy--an unusual presentation of secondary hypertension]

INTRODUCTION

Renal oncocytoma accounts for 5-7% of primary renal neoplasms. It is usually, diagnosed in asymptomatic patients and is characterized by a benign behavior without invasion of adjacent tissues or metastasis. Diagnosis during pregnancy is uncommon and to date there have been only a few cases reported in the literature.

CASE REPORT

The authors present the case of a 32-year-old nulliparous woman with uncontrolled hypertension diagnosed at seven weeks gestation. She was referred to our institution at 24 weeks with superimposed pre-eclampsia complicated by acute pulmonary edema and hemodynamic instability requiring mechanical ventilatory support, fetal growth restriction and stillbirth. Etiological study of the hypertensive disorder performed in the postpartum period was consistent with renal oncocytoma.

CONCLUSION

The clinical behavior of renal oncocytoma remains poorly characterized during pregnancy and may lead to an adverse maternal and fetal outcome despite its theoretically benign behavior. It is essential to exclude a possible secondary cause of hypertension in cases that are difficult to control.