Abstract: SA-PO1021

A Rare Case of Renal Oncocytosis with Agent Orange Exposure

Session Information

Category: Nephrology Education

  • 1302 Fellows and Residents Case Reports

Authors

  • Reddy, Amit, University of Mississippi Medical Center, Jackson, Mississippi, United States
  • Sessums, Mary T, University of Mississippi Medical Center, Jackson, Mississippi, United States
  • Henegan, John Clark, University of Mississippi Medical Center, Jackson, Mississippi, United States
  • Manucha, Varsha, University of Mississippi Medical Center, Jackson, Mississippi, United States
Background

During the Vietnam War, more than 3 million veterans were exposed to Agent Orange, an herbicide containing dioxin that has been linked to increased cancer risk. There is sufficient evidence for an association between Agent Orange and hematological disorders, but only a few cases have been reported in relation to renal neoplasms. Here we present a case of bilateral renal masses with right sided renal oncocytosis and Agent Orange exposure in a patient with chronic kidney disease (CKD).

Methods

A 68-year-old Caucasian male with hypertension, CKD, and previous Agent Orange exposure was noted to have an elevated serum creatinine of 1.9mg/dL and blood urea nitrogen of 36mg/dL which triggered further evaluation. He had no recent hematuria, flank pain, or weight loss. A renal ultrasound showed multiple renal masses, and magnetic resonance imaging confirmed these to be concerning for renal cell carcinoma with one mass in the upper pole of the right kidney measuring up to 3.3cm and a second mass in the interpolar region of the left kidney measuring 2.3cm. All nodules were completely confined to the kidney. Preoperative germline testing of a panel of genes in which variants are associated with hereditary renal carcinoma syndromes revealed no pathogenic mutations. Right partial nephrectomy was performed which noted multiple oncocytic nodules ranging in size from a microscopic collection of a few cells to large, grossly visible nodules. Immunostains were negative for AMACR and CK7 and positive for CAM5.2 and CD117, consistent with a diagnosis of renal oncocytosis.

Conclusion

Renal oncocytosis is an extremely rare disorder with multiple oncocytic nodules of the renal parenchyma and is associated with CKD and Birt-Hogg-Dube Syndrome. The incidence is about 4.3% of all solid renal masses. According to literature, there have been only 4 similar cases reported of oncocytosis with Agent Orange exposure but there has been no definitive link. The diagnosis of renal oncocytosis remains a challenge due to the difficulty in distinguishing between benign and malignant lesions with imaging. As with this case, partial nephrectomy allowed for a definitive diagnosis. Renal oncocytosis in this case could be related to CKD and any link to previous exposure to Agent Orange will require further follow-up of patients with this history to determine if it is a risk factor for renal oncocytosis.