Primary squamous cell carcinoma (SCC) of the renal parenchyma is extremely rare, with only nine cases reported.

This study reports a 51-year-old man with primary SCC of the renal parenchyma. The patient was admitted with recurrent dull pain and discomfort in the right lumbar region, which had worsened over 2 weeks, accompanied by painful gross hematuria. SCC antigen (SCCA) levels were elevated, and imaging revealed a renal mass with associated calculi. The patient underwent laparoscopic unilateral nephrectomy and lymph node dissection. Postoperative pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma, with negative renal pelvis and ureter. The pathological stage was Pt3aN1M0. Four months after surgery, the tumor recurred with involvement of the liver, right psoas major muscle, and inferior vena cava. The patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease progression.

We report a case of primary SCC of the renal parenchyma, a rare renal malignancy. The clinical symptoms, laboratory tests, and imaging findings are nonspecific, making accurate and timely diagnosis challenging. According to the literature, for patients with renal calculi accompanied by a renal mass, elevated serum SCCA levels, and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement, the possibility of this disease should be considered.