RESUMO
Objective:To explore the clinicopathological features and prognosis of renal mucinous tubular spindle cell carcinoma (MTSCC).Methods:The clinical data of 16 patients with MTSCC admitted to the First Affiliated Hospital of Zhengzhou University from July 2013 to July 2022 were retrospectively analyzed. There were six male cases and ten female cases. The mean age was (56.4±11.4) years old. Among them, 10 cases were asymptomatic, two complained of hematuria, three complained of lumbar pain, and one complained of lower limb pain. Twelve cases underwent preoperative enhanced CT examination, 6 cases of ultrasound examination, 3 cases of MRI examination, and 1 case of bone scan. Imaging manifestations showed that the masses were round or round-like with clear borders. Two cases combined with hemorrhage and three cases combined with calcification. Five cases showed exophytic growth, 10 cases partially exophytic, and 1 case completely endophytic. The maximum diameter of the tumor was (65.7±27.4) mm. The tumors were located in the left kidney in 11 cases and in the right kidney in 5 cases. The tumors were mildly delayed-enhancing under enhanced CT, long/short T1 signal mixed with long/short T2 signal under MRI, and diffusion-limited high signal under DWI. The tumors were hypoechoic masses without obvious blood flow signals under ultrasound. Twelve cases were diagnosed as renal occupying neoplasms, 2 cases were suggested as lack of blood supply renal tumor, and one was considered renal tumor rupture and bleeding. In one case, a bone scan suggested metastasis to the thoracic spine and pelvis. The metastatic renal tumor was diagnosed, and a renal puncture was performed to clarify the pathology. Eleven patients underwent laparoscopic radical nephrectomy, and 4 patients underwent partial nephrectomy. One case was metastasized without surgery and treated with apatinib mesylate and zoledronic acid.Results:The postoperative pathological specimens showed grayish, grayish-yellow, or grayish-red masses with a soft or medium texture. No perinephric, ureteral, or adrenal invasion was seen in all tumors. Microscopically, the tumor cells were round and ovoid. The tumor cells were arranged in tubular and striated shapes, and mucus pools were locally visible. No sarcomatous component was seen in all tumors. There were 9 patients with pT 1N 0M 0, 6 patients with pT 2N 0M 0, and 1 patient with pT 1N 0M 1. After operation, 2 patients with pT 2N 0M 0, who underwent laparoscopic radical nephrectomy were treated with pazopanib and sunitinib, respectively. All patients were followed up for a median of 50.7(25.8, 75.0)months, 15 patients were free of recurrent metastases, and 1 patient with pre-puncture metastasis died due to tumor progression of multiple pulmonary and bone metastases, with a survival of 16.9 months. Conclusions:Renal MTSCC is rare, mostly found on physical examination, with female patients predominantly, and imaging shows a lack of blood supply tumor. Surgery is the primary treatment method. Partial nephrectomy or radical nephrectomy could be chosen according to the tumor stage, kidney function, and patient's underlying condition, and patients have a good prognosis.