Abstract BACKGROUND Kidney cell carcinoma corresponds to the 14th cause of incidence in cancer in the world. Mortality is about 12.8 ASR in USA and 3.8 in Colombia. Metastatic disease corresponds to 14% of the patients, having worse prognosis compared to those patients with local or locally advanced disease. We want to share our experience of a patient with brain metastatic disease in clear cell carcinoma of the kidney, treated with TKI, IO and ketogenic metabolic therapy (KMT) with outstanding results. Case summary: 65-year-old female, first diagnosed in 2011 with a clear cell carcinoma stage III, due to pT3aNxM0 at diagnosis, managed with radical nephrectomy. After this patient was 3 years free of disease, she developed in 2014 a meta-chronic papillary thyroid carcinoma stage III, due to T1N1M0, managed with total thyroidectomy plus nodal dissection, and adjuvant iodine therapy with 100 mci. In 2019 the patient presented a pulmonary new lesion, with confirmation of clear cell carcinoma, and was treated with pazopanib due to poor tolerance to sunitinib. In September 2022 the patient presented four lesions in both cerebral hemispheres, mainly involving the right frontal lobe as well as the mesial region of both temporal lobes. Neurosurgery performed a biopsy, confirming clear cell carcinoma. The patient received IMRT holoencephalic over 5 daily sessions. We started treatment with nivolumab in September 2022. After receiving 5 cycles of IO, the patient consulted due to new onset of convulsion, documenting edema of the main lesion, and neurologic worsening. After evaluating the case, we started anticonvulsive treatment and a short period of steroid, with recovery of her function. We used this treatment for around 10 days, and continued immunotherapy and anti-convulsant therapy. In January 2023, we started KMT, at a relation 3:1, measuring ketones and neurologic status constantly. After confirmation of ketones in urine or blood, we started adjustment of therapy to improve compliance. In July 2023, the patient didn’t require assistance to medical appointments, was capable of being free of anticonvulsive therapy, and her cognitive functions were all preserved. In January 2024, the patient remained with partial response, and dietary supplementation (ketovie) was stopped. CONCLUSION This case supports the use of KMT in clear cell renal carcinoma scenarios, in which it can be associated with a synergistic effect to ITK and/or immunotherapy, as well as radiotherapy modalities, improving progression-free survival and functional improvement without increasing toxicity.