(UroToday.com) The 2021 American Urological Association (AUA) Summer School series included a session on the Evaluation and Management of Adrenal Masses moderated by Dr. Neal E. Rowe, and a presentation by Dr. Thomas McGregor discussing radiofrequency ablation of adrenal masses. Dr. McGregor started his presentation by highlighting a case of a 72-year-old male who presented with hematuria and right flank pain for one month. The patient had a BMI of 36 kg/m2 and a medical history consistent with diabetes mellitus, hypertension, and coronary artery disease. CT scan was consistent with a large enhancing right renal mass:
Imaging demonstrated that the patient did not have lymph node nor adrenal gland involvement. The patient subsequently underwent a right laparoscopic radical nephrectomy, with pathology demonstrating an 11.4 cm tumor, clear cell renal cell carcinoma, grade 3, with negative margins, pT3a secondary to peri-renal fat invasion. On follow-up imaging two years later, the patient was noted to have 2 cm left adrenal mass:
A functional workup was negative and the left adrenal mass was subsequently biopsied and noted to be clear cell renal cell carcinoma. Full restaging of the patient was negative and the left adrenal lesion was deemed a solitary metastasis.
Dr. McGregor notes that the gold standard for treatment of solitary renal cell carcinoma metastasis in medically fit patients is surgery (preferably minimally invasive), but that radiofrequency ablation is now an alternative treatment modality. This can be used for all adrenal tumor types, including functioning, non-functioning, malignant and benign. Indications for adrenal mass radiofrequency ablation include an isolated metastasis to the adrenal gland, those that are no eligible for surgery secondary to medical comorbidities, and patient preference for a less invasive approach. The process of radiofrequency ablation includes a multidisciplinary approach, including interventional radiology, urology, endocrinology, anesthesiology. Close intraoperative monitoring is important, utilizing IV sedation. Image guidance for radiofrequency ablation includes:
- CT – used to guide probe insertion in real-time
- Ultrasonography – used as an adjunct, but is body habitus dependent
- MRI – can be used for cryoablation
Positioning for radiofrequency ablation is typically in the prone position with the ipsilateral side down, allowing for easy percutaneous access to the mass:
Complications of radiofrequency ablation include (i) hypertensive crisis secondary to release of catecholamines, with a higher risk if normal adrenal tissue is present, (ii) hemorrhage, (iii) pain, (iv) pneumothorax, and (v) adrenal insufficiency.
Referring back to the aforementioned case, Dr. McGregor notes that this patient was very comorbid with worsening COPD, but was very motivated for treatment and thus chose to have this mass ablated. In summary, Dr. McGregor emphasized that percutaneous techniques can be successful in treating adrenal tumors, with patient selection being crucial for successful outcomes.
Presented by: Thomas McGregor, MD, FRCSC, Queen’s University, Kingston, Ontario, Canada
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the AUA2021 May Kick-off Weekend May 21-23.