A 43-year-old man who had a history of right renal calculus presented to a nearby hospital with a chief complaint of asymptomatic gross hematuria. A left renal tumor was suspected based on plain abdominal CT, and he was referred to our department. Physical examination revealed no abnormality in the chest, the abdomen or the extremities. Laboratory data on admission revealed mild leukocytosis, with leucocyte of 10.5 × 103/μL, mild hypochromic anemia, with hemoglobin of 12.9 g/dL, and mild inflammatory reaction, with erythrocyte sedimentation rate (ESR) of 24 mm at the first hour, C-reactive protein (CRP) of 4.0 mg/dL. Urinalysis revealed erythrocyte count of 50-99/HPF and no pyuria or bacteriuria. Urine cytology was class I and showed no atypical cells. A dynamic CT study revealed a tumor (8 × 7 cm in diameter) in the upper pole of the left kidney (Figures ) and which showed contrast enhancement in the early phase (Figures and ) and extended into the left renal pelvis and the ureter (Figures ). There was also contrast enhancement at this site (Figures and ). In addition, a nodule with 8 mm in diameter was found in the S5 segment of the left lung (Figure ), and para-aortic lymph nodes enlargement were observed (Figure ). Cystoscopy revealed no obvious tumorous lesion. The tumor was diagnosed as left RCC (cT3aN2M1), and transabdominal left nephrectomy and hilar lymph node dissection were performed. Also total ureterectomy including cuff resection of bladder wall was additionally performed because intraoperative histopathological examination couldn't rule out urothelial carcinoma.
Figure 1 Horizontal section of preoperative abdominal CT. Plain (A), early-phase contrast enhancement (B), and late phase (C) showed contrast enhancement. A tumor thrombus in the left renal pelvis (D, arrow), and its contrast enhancement was similar to the main (more ...)
Coronal section of preoperative abdominal CT. A solid tumor in the upper pole of the left kidney (A) and the tumor thrombus (B) showed early-phase contrast enhancement.
Preoperative CT images showed a nodule in the left lung (A, arrow), and para-aortic lymph node enlargement (B, arrow).
Histopathological examination: The macroscopic findings of the excised tumor were a yellow color and no hemorrhage was observed in its interior. There was a protrusion into the renal sinus fat, renal pelvis and a cord-shaped tumor thrombus of approximately 17 cm extending to the lower ureter (Figure ). Histologically, atypical epithelium with severe necrosis, invasion and proliferation of these atypical cells were observed. In all areas of the renal tumor but lymph nodes, cytoplasm of tumor cells contained glycogen (Figure and ). Immunostaining was positive for CD10 and vimetin (Figure and ). According to these findings, the tumor was diagnosed as clear cell RCC (G2 > G3 >> G1, INFβ, v(+), pT3apN0). No malignancy was observed in the surrounding renal pelvic or ureteral mucosa.
The macroscopic findings of the long tumor thrombus.
Histological findings (A; HE, ×40, B; HE, ×200). Immunostaining was positive for CD10 and vimetin (C, D; ×100).