Giant Nonfunctioning Carcinoma of the Adrenal Cortex Mimicking Renal Cell Carcinoma: A Diagnostic Dilemma
Azhar A. Khan, Iqbal S. Shergill, Rizwan Hamid, and Sandeep S. Gujral
Adrenocortical carcinoma is a rare, highly malignant neoplasm that originates in the adrenal cortex and is difficult to differentiate from renal cell carcinoma, especially if it is gigantic and nonfunctional. We report the case of a 40-year-old man with an incidental mass in the right upper abdomen. Magnetic resonance imaging revealed that the mass originated from the right kidney and was highly suggestive of renal cell carcinoma. However, histologic examination after radical nephrectomy confirmed the mass to be an adrenocortical carcinoma compressing the kidney. We discuss the obscurity and implications of such a diagnosis. UROLOGY 70: 178.e1-178.e2, 2007. @ 2007 Elsevier Inc.
A drenocortical carcinoma is a rare malignant growth, affecting only 1 or 2 persons per 1 mil- lion population, which originates in the cortex of the adrenal gland.1 They are generally found at an advanced stage and are usually associated with poor prog- nosis, especially when they are nonfunctioning. We herein describe the case of a giant adrenocortical carci- noma that was diagnosed as renal cell carcinoma (RCC) preoperatively and review the literature to describe the difficulties in reaching a preoperative diagnosis in such cases.
CASE REPORT
A 40-year-old man was incidentally found to have a large mass in the right upper abdomen. Magnetic resonance imaging (MRI) revealed the mass as originating from the right kidney (Fig. 1). It was highly suggestive of renal cell carcinoma (RCC). The case was further discussed in a multidisciplinary team meeting comprising urologists, ra- diologists, and oncologists. Initial diagnosis made by the radiologist was maintained. There was no associated lymphadenopathy or distant metastases. The patient un- derwent a right radical nephrectomy, which showed a 30 × 25 × 25-cm mass (Fig. 2). Peroperatively it seemed to originate from the kidney, and no distinction could be made with the adrenal gland. However, histologic exam- ination confirmed the mass to be an adrenocortical car- cinoma compressing the kidney, which had undergone complete atrophy.
The patient made a smooth postoperative recovery. He was reviewed in light of histopathologic diagnosis. He did not show any clinical signs of adrenocortical disease. His
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urinary and biochemical profile related to the adrenal gland was within the normal range. He remains asymp- tomatic 16 months after operation.
COMMENT
Adrenocortical carcinomas are rare cancers occurring in the endocrine tissue of the adrenals. Approximately 80% of adrenal tumors are functional.2 Functional tumors are more common in children and young women, whereas nonfunctional tumors occur more frequently in older patients.3 It is uncertain whether nonfunctional tumors are truly so or whether the metabolites are so low that they neither cause physiologic change nor can be picked
From the Bristol Urological Institute, Bristol; and Harold Wood Hospital, Essex, United Kingdom
Address for correspondence: Azhar Khan, Bristol Urological Institute, Southmead Hospital, Bristol, United Kingdom. E-mail: docazhar@gmail.com
Submitted: October 12, 2006; accepted (with revisions): March 12, 2007
up by the available assays. Computerized tomography (CT) or MRI is used for diagnostic purposes. In small (3 to 6-cm) lesions fine-needle biopsy can be performed. If the aspirate is diagnostic then up to 95% of adrenal lesions can be accurately diagnosed.4
Fimmano et al.5 reported a similar case of a large nonfunctioning adrenal carcinoma with a 24 × 18-cm mass. Their patient had a preoperative fine-needle biopsy suggestive of RCC without any clinical signs of adrenal disease. However, peroperatively the mass seemed to be of adrenal origin and was distinct from the kidney, which was preserved. Kunieda et al.º reported a patient in whom a giant adrenocortical carcinoma was found to have re- curred in the contralateral adrenal gland and intrapelvic cavity 6 years after his initial operation. They also con- cluded that larger tumors are linked with better prognosis because aggressive tumors give rise to distant metastases and therefore become symptomatic at an early stage.
Computerized tomography or MRI can be used for diagnosis of RCC. The radiologic diagnosis has a sensi- tivity of more than 90%. A fine-needle aspiration biopsy is not recommended because this has a high false-nega- tive rate.7 Selective angiography and adrenal venography can distinguish tumors of the adrenal gland from tumors of the upper pole of the kidney.
It is obviously important to differentiate between ad- renal and renal tumors preoperatively. Although radical surgical excision can be curative for patients with local- ized malignancies, only 30% of these malignancies are confined to the adrenal gland at the time of diagnosis.8 If the diagnosis is known before surgery, CT and/or MRI of the abdomen can provide useful information about local invasion or spread to the kidney. Positron emission to- mography may be effective in identifying unsuspected sites of metastases.9 Even in the presence of a giant adrenocortical carcinoma, involvement of the kidney can be assessed during the operation, and attempts can be made to preserve the kidney.5
However, this differential from kidney tumors might not always be possible. To our knowledge, there is no reported case of RCC greater than 20 cm. Hence, we believe a high index of suspicion should be maintained in tumors larger than 20 cm to make a correct diagnosis, to either save the kidney or be prepared to deal with adrenal pathology both preoperatively and postoperatively.
References
1. Copeland PM: The incidentally discovered adrenal mass. Ann In- tern Med 98: 940-945, 1983.
2. Luton JP, Cerdas S, Billaud L, et al: Clinical features of adrenocor- tical carcinoma, prognostic factors, and the effects of mitotane therapy. N Eng J Med 322: 1195-1201, 1990.
3. Wooten MD, and King DK: Adrenal cortical carcinoma: epidemi- ology and treatment with mitotane and a review of the literature. Cancer 72: 3145-3155, 1993.
4. Nguyen GU, and Akin MR: Fine needle aspiration cytology of the kidney. Ren Pelvis Adrenal Clin Lab Med 18: 429-459, 1998.
5. Fimmano A, Pettinato G, Bonuso C, et al: Giant, non-functioning carcinoma of the adrenal cortex. N Eng J Med 345: 700, 2001.
6. Kunieda K, Saji S, Mori S, et al: Recurrence of giant adrenocortical carcinoma in the contralateral adrenal gland 6 years after surgery: report of a case. Surg Today 30: 294-297, 2000.
7. Herts BR, and Baker ME: The current role of percutaneous biopsy in the evaluation of renal masses. Semin Urol Oncol 13: 254-261, 1995.
8. Norton JA: Adrenal tumors, in DeVita VT Jr, Hellman S, and Rosenberg SA (Eds): Cancer: Principles and Practice of Oncology, 7th ed. Philadelphia, Lippincott Williams & Wilkins, 2005, pp 1528- 1539.
9. Becherer A, Vierhapper H, Pötzi C, et al: FDG-PET in adrenocor- tical carcinoma. Cancer Biother Radiopharm 16: 289-295, 2001.