Adrenocortical Oncocytoma — A Rare Tumor of Undefined Malignant Potential: Report of a Case

Adrenocortical oncocytomas are exceptionally rare. To our knowledge, only 23 cases have been reported in the world literature, most of which were benign and nonfunctioning. We report a case of adrenocortical oncocytoma diagnosed by pathological examination of an extirpated right adrenal mass in a young woman. We discuss this case and review the literature on this unusual entity.     

Non-hormonal adrenocortical adenoma with oncocytoma-like appearances

We report a case of non-hormonal adrenocortical adenoma. The tumor was removed en block with the adrenal gland. The specimen was 5.0 X 4.5 X 3.0 cm, weighed 30 g and was solid. Histologically, this tumor had an oncocytoma-like appearance. However, as there is no concept of oncocytoma in connection with adrenocortical adenoma, this case was diagnosed as adrenocortical adenoma. A case with such histological findings has never been reported.     

Laparoscopic approach to a large adrenocortical oncocytoma: A case report and review of the literature

INTRODUCTIONAdrenocortical oncocytomas are extremely rare tumors, considered to be non-functional and of low malignant potential. Despite the great advance in laparoscopic techniques, there are extremely limited reports of laparoscopic approach of adrenocortical oncocytomas. Herein is presented a challenging case of laparoscopic approach to a large adrenocortical oncocytoma, underlining the safety and feasibility of laparoscopy in the surgical management of these extremely rare adrenal tumors.PRESENTATION OF CASEA 34 year-old male was referred for surgical evaluation after the incidental discovery of a large right adrenal mass, during ultrasound examination due to renal colic. Further imaging evaluation revealed a well circumscribed capsule around the mass was demonstrated, with no evidence of infiltration of the neoplasm to periadrenal tissues. The patient was scheduled for laparoscopic right adrenalectomy, running an uneventful postoperative period. Histopathology revealed the presence of an adrenal oncocytoma.DISCUSSIONRecent studies have demonstrated that approximately one third of adrenocortical oncocytomas are associated with hormonal hypersecretion, as well as that one fifth of them demonstrate malignant biological behavior. From this point of view, there is emerging evidence in favor of the necessity of surgical excision as the treatment of choice. In spite of the progress of laparoscopic surgery, only three cases of laparoscopic excision of these tumors have been reported up to date.CONCLUSIONLaparoscopic surgery offers a safe alternative in confronting adrenocortical neoplasms, even when the biological behavior of the tumors cannot be pre-operatively evaluated in a definite way.     

肾上腺嗜酸细胞腺瘤1例报告并文献复习

目的:探讨肾上腺嗜酸细胞腺瘤的临床及病理特点。方法:回顾性分析1例肾上腺嗜酸细胞腺瘤患者的临床资料:男,54岁,体检时B超发现左肾上腺区肿物,CT检查发现6.0cm×5.3cm肾上腺区肿物。肾素、醛固酮、儿茶酚胺实验值均正常。行肾上腺肿物切除术。结果:术中发现肿物体积较大,包膜完整光滑,与周围组织无粘连,肿物表面血管较为丰富,术中触碰肿物,血压无波动,遂完整切除肿物。术后病理检查显示肿瘤细胞嗜酸性,内部充满颗粒,诊断为肾上腺嗜酸细胞腺瘤。随访6个月无复发。结论:肾上腺嗜酸细胞腺瘤是一种具有潜在恶性的良性肿瘤,可手术切除,但术后需密切随访。     

Oncocytoma in a horseshoe kidney

Renal oncocytoma is an unusual tumor that has been identified with increasing frequency during the last decade, and more than 150 cases have been reported in the literature, including multifocal and bilateral tumors. We report a case of oncocytoma in a horseshoe kidney. Oncocytoma and tumors in horseshoe kidneys are discussed.     

Adrenocortical oncocytoma. A true nonfunctioning adrenocortical tumor

We studied three cases of adrenocortical neoplasms that were detected incidentally after radiological examination of the abdomen. These cases did not demonstrate any clinical evidence of adrenocortical abnormalities, such as virilization. Macroscopically, the tumors were light to dark tan on cut surface. Light-microscopic examination revealed compact cells with abundant lipid-sparse eosinophilic cytoplasm and occasional enlarged nuclei. In one case, ultrastructural observation demonstrated abundant mitochondria. Immunohistochemical examination of all of the adrenocortical steroidogenic enzymes showed that none of the cases had immunoreactivity. No mitotic activity and no vascular invasion was observed. The postoperative course were uneventful. The follow-up interval varied from 8 to 27 months. These three neoplasms apparently represent the first reported cases of adrenocortical oncocytoma. They can be considered true nonfunctioning adrenocortical neoplasms because steroidogenic enzymes required for corticosteroid biosynthesis were not expressed in the tumor cells.     

肾上腺嗜酸细胞腺瘤一例报告并文献复习

目的报道1例肾上腺嗜酸细胞腺瘤患者的临床及病理特点。方法患者,男,37岁,体检发现左肾上腺肿物15 d入院。既往否认高血压、低血钾等病史。实验室检查血钾、血儿茶酚胺、血皮质醇、立卧位肾素血管紧张素、醛固酮、尿3-甲基-4-羟基苦杏仁酸、尿17-羟皮质类固醇、17-酮皮质类固醇均正常。B超及CT检查示左肾上腺区肿物,直径约7 cm。术前诊断为左肾上腺区肿物,行后腹腔镜下左肾上腺肿物切除术。结果术中发现肿物体积较大,包膜完整光滑,与周围组织无粘连,肿物表面血管较为丰富,术中碰触肿物,血压无波动,完整切除肿物。术后病理检查示肿瘤细胞嗜酸性,内部充满颗粒,诊断为肾上腺嗜酸细胞腺瘤。随访2个月无复发。结论肾上腺嗜酸细胞腺瘤是一种具有潜在恶性的良性肿瘤,可手术切除,但需密切随访。     

Oncocytoma associated with acquired cystic disease of kidney (ACDK): a case report

A case of renal oncocytoma associated with acquired cystic disease of kidney (ACDK) in a 56-year-old man is reported. He had received hemodialysis for 15 years because of chronic renal failure. Computed tomography (CT) was performed because of distention in the upper abdomen, revealing a right renal tumor. He underwent laparoscopic right nephrectomy, and was diagnosed with renal oncocytoma. There have been reported 8 cases of renal oncocytoma in hemodialysis patients, and our case was the third one associated with ACDK in the literature.     

Renal oncocytoma associated with necrotizing glomerulonephritis

A case of renal oncocytoma associated with focal segmental necrotizing glomerulonephritis is described. The patient showed haematuria, mild proteinuria and arterial hypertension; the diagnosis was made after right nephrectomy performed because of the presence of a renal mass. A severe re-activation of the glomerulonephritis was observed 15 months after the nephrectomy and a steroid and immunosuppressive therapy was started. Our case is the first reported in which the removal of renal oncocytoma is not followed by the disappearance of renal symptoms, as currently reported in literature, suggesting that the two diseases are not always related.     

Renal Oncocytoma Associated with Necrotizing Glomerulonephritis

A case of renal oncocytoma associated with focal segmental necrotizing glomerulonephritis is described. The patient showed haematuria, mild proteinuria and arterial hypertension; the diagnosis was made after right nephrectomy performed because of the presence of a renal mass. A severe re-activation of the glomerulonephritis was observed 15 months after the nephrectomy and a steroid and immunosuppressive therapy was started. Our case is the first reported in which the removal of renal oncocytoma is not followed by the disappearance of renal symptoms, as currently reported in literature, suggesting that the two diseases are not always related.     

Retroperitoneoscopic partial adrenalectomy for large adrenocortical oncocytoma

A young woman had mild hypertension, and on evaluation, a large tumor arising from the right adrenal gland was found. The tumor was hormonally inactive. Retroperitoneoscopic partial adrenalectomy was carried out. The histopathology report described adrenocortical oncocytoma.     

False positive 18F-FDG PET scan in adrenal oncocytoma

18F-FDG whole-body positron emulsion tomography (18F-FDG PET) has become an established imaging modality for a variety of cancers. Today, 18F-FDG PET is utilized to differentiate benign from malignant non-functioning adrenal masses. In this report, a 25-year-old woman presented with a 2-month history of left flank pain. Abdominal CT revealed a left 6.5 x 4.5 cm adrenal mass with regular margins and focal calcification. To make a differential diagnosis, 18F-FDG PET was performed. Preoperative laboratory studies showed that the mass was non-functioning. A left adrenalectomy was performed through a left subcostal incision. The final pathologic evaluation revealed adrenal oncocytoma. We present the disassociation between preoperative 18F-FDG PET and pathologic findings of a benign adrenocortical oncocytoma.     

Preoperative diagnosis of renal oncocytoma and treatment possibilities

We report 2 cases of renal oncocytoma and review the literature. A number of radiological, cytological and ultrastructural differential features of oncocytoma that are known today make preoperative diagnosis of this tumour possible. Analysis of the reported cases allows to conclude that oncocytomas are of universally benign character with a very good prognosis. Metastases have not been documented. Thus we suggest that many patients with oncocytoma could be spared the operation of nephrectomy. Partial kidney resection or heminephrectomy are to be preferred with solitary oncocytomas of a moderate size.     

Oncocytoma of kidney.

Oncocytoma is a rare, benign tumor of the kidney of which only 20 cases have been reported previously in the literature. We document 2 additional cases of renal oncocytoma and review the salient gross and microscopic features which characterize this tumor.     

Nonparotid parapharyngeal oncocytoma: A case report and literature review

Oncocytoma is a rare, benign salivary neoplasm composed of mitochondria‐rich cells called oncocytes. Although oncocytoma usually occurs in the parotid glands, it has much less commonly been reported to occur in minor salivary gland tissues. Although there have been a few reported cases of oncocytomas being found in the parapharyngeal space, most if not all cases seem to be extensions of deep lobe parotid tumors. We present a case of a 73‐year‐old man with a previous history of prostate cancer that had the incidental finding of an ¹⁸F‐fluorodeoxyglucose (FDG) image of a highly avid parapharyngeal space lesion noted on a follow‐up positron emission tomography–computed tomography (PET/CT) scan. Excision of the mass, through a transcervical approach, demonstrated it to be an isolated oncocytoma of the parapharyngeal space, noncontiguous with the parotid gland. Based on our literature search, this may be the first such reported case. A brief review of the available literature examining the known body of knowledge regarding these neoplasms is presented. © 2009 Wiley Periodicals, Inc. Head Neck, 2010     

Unilateral renal oncocytoma: A case report

A case of unilateral renal oncocytoma is reported. Diagnosis, clinical features and management of the tumour are discussed in the light of international literature.The value of angionephrography in the diagnosis of the tumour and in the preoperative planning of surgical therapy is emphasized.     

Bilateral renal oncocytoma: report of 2 cases and literature review

We report on 2 patients with bilateral renal oncocytoma treated in the last 5 years. One patient underwent bilateral partial nephrectomy for a solitary tumor in each kidney. Both tumors were confirmed to be renal oncocytomas by light and electron microscopic examination. After 4 years this patient had no evidence of local recurrence or distal metastasis. The second patient presented with bilateral multiple renal oncocytomas. Transabdominal bilateral renal exploration revealed 2 tumors in the right kidney and 3 tumors in the left kidney. Right radical nephrectomy and enucleation of the left renal tumors were performed. Examination by light and electron microscopy confirmed that all tumors from both kidneys were oncocytomas. Only 8 cases of bilateral renal oncocytoma have been reported in the literature, including our 2 cases. In 6 of these 8 cases the tumors were multicentric, which may be a characteristic of bilateral renal oncocytoma. Recognizing the coexistence of multicentricity and bilaterality is important because more conservative treatment is required. However, a favorable prognosis may still be anticipated.     

Renal oncocytoma in Taiwan

BACKGROUND: Renal oncocytoma has been repeatedly reported in Western countries, but only a few cases have been reported in Eastern countries. This study aims to review the clinical course of renal oncocytoma in an Eastern country such as Taiwan. MATERIALS AND METHODS: Sixteen cases of renal oncocytoma seen between 1987 and 2002 at Chang Gung Memorial Hospital, Taipei, Taiwan, were studied. RESULTS: Preoperatively, all patients were diagnosed to have renal cell carcinoma, following various radiologic studies. Perioperatively, frozen sections of three patients indicated renal oncocytoma in two and renal cell carcinoma in one. Renal oncocytoma has marked similarities to renal cell carcinoma, according to various radiologic, cytologic, and pathological investigations, so an accurate diagnosis is difficult to achieve, either preoperatively or perioperatively. Therefore, rather than being treated with partial nephrectomy, all patients were treated aggressively with unilateral radical nephrectomy. Postoperatively, all 16 patients were followed up, from 12 to 189 months, with a mean of 58.7 months. Notably, all patients survived with no evidence of tumor recurrence. CONCLUSIONS: The experience in Taiwan is generally that renal oncocytoma behaves benignly, as reported in other areas. The excellent prognosis associated with this tumor appears to indicate that partial nephrectomy may suffice for removing the tumor, while sparing other unaffected renal parenchyma.     

Neoplasm to neoplasm metastasis. A renal oncocytoma with metastatic bronchogenic carcinoma

An unusual case of metastasis of neoplasm to a benign neoplasm is reported. The initial malignancy, a small-cell bronchogenic carcinoma, was found to have metastasis to a renal oncocytoma. A review of the literature indicates, according to our knowledge, no similar case.     

Renal Oncocytoma in Taiwan

Background. Renal oncocytoma has been repeatedly reported in Western countries, but only a few cases have been reported in Eastern countries. This study aims to review the clinical course of renal oncocytoma in an Eastern country such as Taiwan. Materials and Methods. Sixteen cases of renal oncocytoma seen between 1987 and 2002 at Chang Gung Memorial Hospital, Taipei, Taiwan, were studied. Results. Preoperatively, all patients were diagnosed to have renal cell carcinoma, following various radiologic studies. Perioperatively, frozen sections of three patients indicated renal oncocytoma in two and renal cell carcinoma in one. Renal oncocytoma has marked similarities to renal cell carcinoma, according to various radiologic, cytologic, and pathological investigations, so an accurate diagnosis is difficult to achieve, either preoperatively or perioperatively. Therefore, rather than being treated with partial nephrectomy, all patients were treated aggressively with unilateral radical nephrectomy. Postoperatively, all 16 patients were followed up, from 12 to 189 months, with a mean of 58.7 months. Notably, all patients survived with no evidence of tumor recurrence. Conclusions. The experience in Taiwan is generally that renal oncocytoma behaves benignly, as reported in other areas. The excellent prognosis associated with this tumor appears to indicate that partial nephrectomy may suffice for removing the tumor, while sparing other unaffected renal parenchyma.