| ORIGINAL REPORTS |
ABSTRACT
Two cases are reported of patients with a single metastasis in the contralateraladrenal, one and nine years respectively after nephrectomy for localizedcancer in the opposite kidney. These types of metastases are usually asymptomaticthey do not appear with signs of adrenal insufficiency, they are detectedincidentally and the diagnosis is confirmed mainly with CT scan, whichcomprises the method of choice for the detection of such types of metastases.Many adrenal metastases probably have been overlooked in the past whenadvanced imaging techniques were not available. Both patients underwentadrenalectomy and replacement therapy with corticosteroids.
Approximately 50% of all patients with renal cell carcinoma either presentwith metastases at diagnosis or will have metastatic disease after nephrectomy1.In order of decreasing frequency, the most common metastatic sites arethe lungs, lymph nodes, liver, bone, contralateral kidney and ipsilateraladrenal glands. Adrenal involvement has been reported in 7 to 19% of autopsystudies.1,3
Solitary metachronous metastatic involvement of the contralateral adrenalfrom renal cell carcinoma is rarely diagnosed during life and only 4 caseshave been reported.4,5 Recent advances in imaging techniqueshave allowed the diagnosis of adrenal involvement by renal cancer. Twocases of contralateral adrenal metastasis are reported 1 and 9 years afterradical nephrectomy for localized renal cell carcinoma. Both patients underwentadrenalectomy and steroid replacement therapy.
Case 1
Female, aged 68 years, underwent radical right nephrectomy for localizedrenal cancer 1 year ago (Fig.1).During surgery the existing embolus in the right renal vein was removed.Distant metastases were not found. During a follow up examination 6 monthslater, the CT scan showed a suspicious enlargement of the left adrenal(Fig.2).The ultrasound tomography was not helpful in identifying the nature ofthe enlargement. MRI(Fig.3)and selective angiography(Fig.4)showed either a suspicious primary tumour of the left adrenal or the presenceof a metastatic disease. The biochemical and hormonal laboratory testswere normal. A left adrenalectomy was performed through a left thoracoabdominalincision and a tumour (4 x 1 cm in diameter) was removed(Fig.5).The pathological examination of the tumour revealed a metastatic renaltumour of moderate differentiation and of the same type of cancer whichwas removed before one year(Fig.6).Preoperatively the patient started replacement therapy with hydrocortisone100mg tid until the 3rd postoperative day, followed by cortisone acetate25mg per os for life. She is in good condition 4 months after surgery.
Case 2
Male, aged 72 years, was admitted due to fever, anemia and loss of bodyweight - approximately 7 kg. in the previous 2 months. In 1981 he underwenta left radical nephrectomy due to cancer of the corresponding kidney. Afterbeing admitted, only anemia (Hematocrit = 29.8) and a rise in ESR (9Omm)were discovered. The intravenous pyelography revealed a mass in the upperpole of the right kidney and the CT scan confirmed its presence in thearea of the right adrenal (Fig.7).Selective angiography was then performed, which showed the presence ofa hypervascular mass(Fig.8).Further tests with bone scans and CT scans were negative for the presenceof metastases. The biochemical and hormonal laboratory tests were normal.The tumour was removed en-bloc through a right thoracoabdominal incision.The pathological examination showed a mass of 10 cm.(Fig.9)which histologically presented the characteristics of a metastatic renalcancer of moderate differentiation and of the same type of cancer of thecontralateral kidney removed 9 years ago(Fig.10).
The patient immediately started replacement therapy with corticosteroidshe was well, until 7 months later when the CT scan showed a suspiciousmass between right kidney and inferior vena cava(Fig.11).Immunotherapy was started with Interferon a-2a of 18 MU IM 3 times a weekfor 3 months but with no response. Generalized metastases developed andhe died nine months later.
Discussion
Adrenal metastases usually result from breast cancer, lung cancer, andmelanoma6. Approximately, 3 percent of all adrenal metastasesare from renal cancer. The incidence of the localization in the adrenalsis probably explained by the type of adrenal blood supply, by their highflow volume and by the type of their capillary network, which has a sinusoidalvascular pattern. On the contrary, the spleen which has the same type ofblood supply is a rare site for metastases.7
Solitary metastases in the adrenals have been reported in 1.6-3.6% ofpatients with renal cancer8. The most common sites for metastasesof the renal cancer is the lung and the bones2. Contralateralmetastases from renal cancer are very rare. Metachronous metastatic involvementof the contralateral adrenal from renal cell carcinoma is rarely diagnosedduring life, and with only 4 cases mentioned in the literature. 4,5
| Reference | Age / Sex | Side of Primary | Detection of Adrenal Metastases | Diagnostic Procedure | Treatment | Follow-up |
| T.K. Huisman and J.P.Sand | 46/M | R | 2 years after nephrectomy | CT | Adrenalectomy (L) | +7Mo NED died +20mo |
| JR (2 cases) | 69/M | R | 4 years after nephrectomy | CT | Adrenalectomy (L) | +12Mo NED sol. lung met. Excised alive +36 mo |
| J. Plawner | 70/M | L | 6 years after nephrectomy | CT | Adrenalectomy (R) | +60Mo NED |
| (2 cases) | 57/M | R | 7 years after nephrectomy | CT | Adrenalectomy (R) | +32Mo NED |
R = Right
K = Left
CT = Computerized Tomography
NED = No Evidence of Disease
A characteristic of adrenal metastases is that they either remain "silent",without showing any symptoms, (as in Case 1) or they are diagnosed whenthey become very large (as in Case 2). The silent nature of such metastasesis explained as is known that even one tenth of the remaining adrenal tissueis capable of regulating all normal body functions without the appearanceof adrenal insufficiency and with normal cortisone and adrenaline valuesin the blood9.
There is currently general agreement that the CT scan of the thoraxand of the abdomen is the more precise method for the diagnosis of metastasesafter nephrectomy for renal cancer and that the IVP and chest X-ray havebeen replaced by CT scan.
This is also true for the diagnosis of adrenal metastases where thechief method of detection is CT scan. The appearance of these tumours havecharacteristics similar to those of solid renal tumours.
MRI probably gives just as good information. Angiography is still helpfulin the diagnosis of these localizations since the lower adrenal arteriesare usually well demonstrated, especially on the right. The left adrenalartery is less often visualized12.
Low-grade, low-stage renal cell carcinoma carries a good prognosis10.It is therefore desirable to diagnose metastatic lesions while they aresolitary and small. Early diagnosis facilitates aggressive surgical resection.The management of such cases is always adrenalectomy and replacement therapywith corticosteroids for life.
In conclusion, contralateral solitary metastases in the adrenals, afternephrectomy for renal cancer, although rare, are asymptomatic. They donot appear with signs of adrenal insufficiency. They are detected "incidentally"mostly with CT-scan during the follow-up of patients with renal cancer.
A close follow-up of all patients who have undergone nephrectomy forrenal cancer is necessary, especially for patients who are asymptomaticfor many years after the primary operation. Many adrenal metastases probablyhave been overlooked in the past when advanced imaging techniques werenot available.
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