Renal Metastasis of Adenocarcinoma of the Colon

<b>Introduction:</b> Metastasis is a critical factor in colorectal cancer (CRC) outcomes, with 22% of patients presenting with metastasis at diagnosis and an eventual 70% experiencing it. This report highlights a rare case of ascending colon adenocarcinoma with metastasis to the kidney, underscoring the diverse and complex nature of CRC progression. <b>Case Presentation:</b> A 60-year-old man presented with abdominal discomfort, constipation, and rectal bleeding after colonoscopy revealed a colon mass, leading to a diagnosis of adenocarcinoma after colonoscopic biopsy. Initially without distant metastasis, he underwent four cycles of chemotherapy, but follow-up imaging 6 months later showed liver and renal metastases, prompting a colectomy and nephrectomy. Pathological examination confirmed moderately differentiated adenocarcinoma in both the colon and kidney, with staging indicating advanced disease, and the patient succumbed to his illness shortly after surgery. <b>Clinical Discussion:</b> Metastatic carcinomas to the kidney are uncommon, with CRC metastasis being particularly rare, as evidenced by a limited number of cases in the literature. Typically originating from primary tumors in the lung, liver, and gastrointestinal tract, renal metastases often present as well-defined lesions, complicating the differentiation from primary renal cancers. Our case highlights a solitary, well-circumscribed renal metastasis from CRC, emphasizing the diagnostic challenges and the need for careful evaluation in patients with known malignancies. <b>Conclusion:</b> Metastatic carcinoma of the colorectal tract is very rarely reported to the kidney, it does so at a higher stage of the disease with systemic disease and has a poor outcome for the patient.