A 46-year-old female patient presented with a complaint of left lower back pain for one month. One month prior, the patient had developed intermittent left lumbago without radiation pain. She had no urinary irritation, hematuria, fever, night sweats, or other uncomfortable feelings. She had a history of transvaginal myomectomy 7 years ago, left lumbar impact injury 9 years ago, and smoking for 10 years. She denied a history of hepatitis, tuberculosis, hypertension, diabetes, and coronary heart disease. There was no percussion pain in the double renal region, and a 6 x 6 cm mass in the left abdomen could be deeply palpated. In additional, there was no tenderness in the ureteral area or edema in either lower limb. An auxiliary examination revealed the following. Three-phase enhanced CT of the kidney showed decreased perfusion of the left kidney and a cystic low-density shadow in the left renal hilum, with a CT value of approximately 5 +- 10 HU and size of 7.4 x 7.4 cm. There were flocculent and high-density shadows in the cyst; however, there was no enhancement in the lesion and slight enhancement in the wall. In addition, the left renal pelvis was dilated, with no abnormal density shadow and a clear perirenal fat space. A small amount of fluid density under the left renal capsule were observed in the images. In general, no significant differences were found in the three-phase enhancement images. No abnormalities were observed in the right kidney. (Figure 1) Pulmonary CT findings were as follows. Nodules were observed under the pleura of the upper lobe of the right lung with a diameter of approximately 3 mm, and a punctate high-density shadow was observed in the upper lobe of the right lung. No abnormalities were found in the abdominal aorta, bilateral iliac artery, bilateral iliac vein, or inferior vena cava. On transvaginal three-dimensional ultrasound, cervical echo was found to be non-uniform. Routine blood examination showed no obvious abnormalities; blood, liver, kidney, and blood coagulation function were normal. The urine routine test results were abnormal: the erythrocyte count was 50.7/mul and leukocyte count was 171.8/mul. After comprehensive analysis, the admission diagnosis included a left renal tumor, left renal hydronephrosis, and left renal subcapsular effusion.
After admission to our hospital, perioperative preparation improved, and robot-assisted radical nephrectomy was performed under combined intravenous infusion and inhalation anesthesia. We used the da Vinci Xi surgical system of the fourth generation to perform the radical nephrectomy. The transperitoneal approach was adopted instead of the traditional retroperitoneal access approach to view the large tumor. The patient was placed in a lying position with the right oblique at 45 . The incision was at the lateral border of the left rectus abdominis under the 3 cm of the umbilical horizontal line. By cutting the subcutaneous tissue of the skin layer by layer, the sheath of the rectus abdominis, and the peritoneum, we put the first 8 mm trocar into the abdominal cavity, which connected to the robot's third arm, placing the monopolar curved scissors, with keeping the pneumoperitoneum pressure at the 14 mmHg level. Laparoscopy was inserted and the other trocars were established under direct vision. The second 8 mm trocar was established at the width of the two fingers under the xiphoid process, which connected to the robot's first arm, placing the maryland forceps bipolar. The third 8 mm trocar was established at the equidistant position between the above two trocars, which connected to the robot's second arm, placing the laparoscopic lens. The area among the trocars and the operative region was kept as an isosceles triangle. Next, the fourth trocar was established at the position of the 2 cm medial to the iliac crest, which connected to the robot's fourth arm, placing a large needle driver. Finally, we established the fifth 10 mm trocar under the umbilicus as an auxiliary port. (Figure 2C) After examination, it was revealed that approximately 10 cm of the round eminence of the splenic curvature of the colon was protruding into the abdominal cavity. After releasing part of the adhesion, the descending colon adhered to the lateral abdomen, and the left peritoneum was cut along the para-colonic groove. The adhesion between kidney and surrounding tissue was severe, and the adhesion around the tumor was also serious, making it difficult to separate. The nature of the tumor was difficult to judge due to wound bleeding, the unclear relationship between between the tumor and kidney, and serious adhesion of the tumor with the psoas major muscle. Because the possibility of malignancy was high, we performed radical resection of the left kidney, including the tumor and part of the ureter. Dissociating the genital vein, and going upstream along it to the renal hilum, then we saw the renal vein. After using Hem-o-Lok clips to disconnect the genital vein, we then separated the renal vein and dissociated the renal artery in the rear. Next, clipping the renal artery and vein with Hem-o-Lok clips, we dissociated the inferior pole of the kidney to sever the ureter. Finally, with preserving the adrenal gland, the left kidney and tumor was removed completely. In the gross specimen, a mass measuring 7 x 7 cm was observed near the hilum of the left kidney and was associated with the ureter. (Figure 2A) After dissection along the vertical axis, there was an outflow of yellowish gelatinous material, and no neoplasm invasion was found in the renal pelvis or ureter. (Figure 2B) During surgery, approximately 800 ml blood was lost; therefore, 400 ml of plasma and 4 U of red blood cells were infused, and no transfusion reaction was observed. Pathology reports revealed that the volume of the left kidney was 11 x 5 x 7 cm, and the volume of the gray-white cystic mass was 7 x 6 x 5 cm at one pole. There was a large amount of mucus in the tumor, which was a focal grayish yellow color, similar to necrosis. There was a local grayish red color around the kidney, and part of the ureter was adherent. The ureter length was 5 cm, and the broken-end diameter was 0.6 cm. Microscopically, a wide range of mucus lakes was observed, in which floating and irregular glands showed large, deep staining of the tumor nucleus and obvious atypia. The image showed mucinous epithelium and a large amount of mucus. (Figure 3F) Immunohistochemical results were as follows: CDX-2(+), Villin(+), CK7(-), CK20(+), CEA(+), MUC2(+), MUC5AC(+), ER(-), PR(-), P16(-), and CA125(-). (Figures 3A-E) Low-grade mucinous adenocarcinoma of the left kidney was pathologically diagnosis; however metastasis was not diagnosed, suggesting the clinical examination of the appendix. No cancer was found at the end of the ureter or vascular end of the renal hilum.
Results of the routine blood examination on the first day after surgery were abnormal: the white blood cell count was 10.5 x 109/L and percentage of neutrophils was 85.9%. The catheter was removed on the second day after surgery. The CT of the upper, middle, lower abdomen was reexamined on the fourth day after surgery. A low-density shadow in the left accessory area, with a small amount of high-density shadow in the pelvic cavity, was observed; furthermore, no abnormalities were found in the other organs. The drainage tube was removed on the fifth day postoperatively, and the patient was discharged without any complaints of discomfort.
Our patient was very satisfied with our surgical method and therapeutic measures. There was no special discomfort after the operation, and she recovered quickly, feeling better than before. She suggested that we deal with her tumor properly and timely.