Renal Oncocytoma Treated With Stereotactic Body Radiation Therapy in a Patient With Prior Pancoast Tumor

A renal oncocytoma is a benign tumor of the kidney, typically treated surgically or via ablation therapy, while a Pancoast tumor is a rare tumor of the lung apex, most often non-small cell lung cancer (NSCLC), usually managed with neoadjuvant chemoradiation followed by surgery. In this report, we discuss the diagnosis and management of a 72-year-old man who developed a renal oncocytoma and a recurrent Pancoast tumor. At the time of our patient's treatment for his renal oncocytoma, thermal and radiofrequency ablation were not frequently employed, and active surveillance was also not the standard of care. Therefore, a partial nephrectomy was offered but declined by the patient over quality of life concerns. Following a discussion with radiation oncology, the patient instead opted for stereotactic body radiation therapy (SBRT), which was well tolerated. All clinical and imaging follow-up revealed excellent control of the lesion with no progression. To our knowledge, this is one of the first reported cases of an oncocytoma successfully treated with SBRT. The patient's stage 3 NSCLC Pancoast tumor was treated with the vinblastine cisplatin radiation therapy (VCRT) protocol, first developed at the Verspeeten Family Cancer Centre in London, Ontario. It consisted of four cycles of vinblastine and cisplatin, with the last two cycles administered concurrently with radiation therapy. This treatment produced excellent symptom control and an impressive nine years of disease-free survival. When the Pancoast tumor re-emerged at the end of this interval, it was treated with palliative reirradiation, and symptom control was excellent for another 10 months until a right-sided occipital lobe metastatic lesion was discovered and the patient succumbed to his disease. This report provides a clinical example of the viability and safety of SBRT for the treatment of renal oncocytoma. Importantly, SBRT has shown efficacy in treating renal cell carcinoma, the malignant differential of a renal oncocytoma. Clinicians should therefore consider SBRT for a renal oncocytoma when patients decline surgery (or ablation therapy) or when the pathologic diagnosis of the lesion is in doubt. Our case also provides an example of the successful treatment of a non-resectable NSCLC Pancoast tumor with the VCRT regimen and successful palliative re-irradiation of a recurrent Pancoast tumor.