Clinical Effect of Retroperitoneal Laparoscopic Radical Nephrectomy on Renal Cell Carcinoma, the Influence of Renal Function, and the Influencing Factors of Recurrence.

Renal cell carcinoma is abbreviated as renal carcinoma, and its clinical symptoms are basically hematuria, lumbago, and abdomen bump. As people's lifestyles change, the incidence of renal carcinoma continues to rise due to factors such as smoking and obesity. At present, surgical treatment is mostly used in clinical practice. Traditional open radical nephrectomy (ORN) is one of the main methods for clinical treatment of renal carcinoma. However, due to its large wound and large amount of intraoperative blood loss, the renal function of patients after surgery is poor, which is not conducive to the postoperative recovery of patients. Retroperitoneal laparoscopic radical nephrectomy (RLRN) has been widely used in the surgical treatment of renal cancer due to its advantages of small wound, less bleeding, and rapid recovery. The purpose of this study was to investigate the efficacy of RLRN in the treatment of renal cancer patients and its effect on renal function and to analyze the related factors affecting postoperative recurrence of patients. We adopt ORN and RLRN, two kinds of treatment, in patients with renal cancer surgery way, contrast analysis of the two groups of operation time, intraoperative blood loss, postoperative intestinal function recovery time, drainage tube indwelling time, length of hospital stay, and other clinical indicators and renal function indexes and use the single factor analysis and multifactor analysis, the relevant factors that affect kidney cancer patients with postoperative recurrence. The results showed that, compared with ORN treatment, RLRN treatment of renal cancer patients has a short operation time, less trauma, quick recovery after surgery, and fewer complications and can effectively alleviate the renal function injury and the body's inflammatory response, which is worthy of promotion. Postoperative recurrence was related to age, tumor diameter, TNM stage, surgical method, and postoperative immunotherapy.

1. Introduction

Renal cell carcinoma is abbreviated as renal carcinoma, and its clinical symptoms are mainly hematuria, low back pain, and abdominal masses. With the changes in people's lifestyles, smoking, obesity, and other factors have led to a continuous increase in the incidence of kidney cancer, which has seriously endangered the lives and health of people in our country [1, 2]. At present, surgical treatment is mostly used in clinical practice. The traditional open radical nephrectomy (ORN) is one of the main clinical methods for the treatment of renal cancer. However, due to the large wound and the large amount of intraoperative blood loss, the postoperative renal function of the patient is poor, which is not conducive to the postoperative recovery of the patient [3, 4]. Retroperitoneal laparoscopic radical nephrectomy (RLRN) has been widely used in the surgical treatment of renal cancer because of its advantages of small wounds, less bleeding, and rapid recovery [5, 6]. Although surgical treatment is effective, some renal carcinoma patients still have complications such as peritoneal injury after surgery and in severe cases even relapse, which seriously affects the surgical effect. There are two basic approaches to laparoscopic radical nephrectomy: retroperitoneal approach and peritoneal approach [7, 8]. The advantages of the peritoneal approach are broad field of vision, large operating space, and clear anatomical signs. However, its disadvantages are that its influence on the internal organs of the abdominal cavity is more obvious than that of the retroperitoneal approach, and the risk of intestinal anesthesia, organ injury, peritoneal inflammation, and other abdominal diseases is high. Moreover, the previous operation has a great influence on the reapplication of laparoscopy [9, 10]. The advantages of the retroperitoneal approach are less impact on the abdominal organs, less accidental injury, and less tissue separation and resection, and the most important thing is that it does not enter the abdominal cavity, and the possibility of tumor planting and spreading in the abdominal cavity is reduced [11, 12]. The purpose of this study was to explore the efficacy of RLRN in the treatment of renal cell carcinoma patients and its influence on renal function and to analyze the relevant factors that affect the recurrence in patients after surgery. The specific report is as follows.

2. Materials and Methods

2.1. Patients

A total of 106 kidney cancer patients admitted to our hospital from June 2017 to March 2020 were selected as the research objects, including 65 males and 41 females, aged 45–76 years, with an average age of (62.54 ± 8.26) years. Inclusion criteria: all patients were diagnosed as renal carcinoma by imaging examination before operation [13]; they have unilateral kidney cancer, where the healthy side has good renal function index test results; they meet the indications for surgical treatment; clinical data were complete. Exclusion criteria: patients with surgical contraindications; patients with a history of abdominal surgery; patients with cardiopulmonary insufficiency; patients with other malignant tumors; patients with chronic kidney disease and other diseases that affect renal function; patients with mental illness. Using random number table method, 106 patients were divided into control group and observation group, with 53 cases in each group. There was no statistically significant difference in general information between the two groups (P > 0.05), as shown in Table 1.

Table 1

Comparison of general information of the two groups of patients.

Groups	Gender		Age (years)	Tumor location		Tumor diameter (cm)	TNM staging
	Male	Female		Left	Right		I	II	III
Control group (n = 53)	35	18	62.31 ± 8.63	34	19	4.83 ± 0.75	20	24	9
Observation group (n = 53)	30	23	62.77 ± 8.05	31	22	4.86 ± 0.81	18	23	12
t/χ 2	0.994		0.284	0.358		0.198	2097
P	0.319		0.777	0.549		0.844	0.351

2.2. Operation Method

The control group was treated with ORN: After general anesthesia, the healthy lateral position was taken and the lumbar bridge was raised. An incision was made between the 11th and 12th ribs. The kidney pedicle was double ligated and sutured, and the kidney hilum and surrounding lymph nodes were removed; then, the kidney was completely removed. The incision was closed and the drainage tube was placed. During surgery, if there is no clear boundary between the tumor and the adrenal gland, the tissue should be removed for pathological examination. After surgery, a drainage tube was placed and the incision was closed.

The observation group was treated with RLRN: After general anesthesia, the healthy lateral position was taken, the lumbar bridge was raised, and the posterior abdominal cavity was established. An incision was made through the posterior axillary line to insert an expanded balloon into the posterior abdominal cavity, and 500 ml gas was injected and retained for 5 min. Separate the dorsal side of the fascia around the kidney, with the range from the level of the iliac blood vessel to the diaphragm as the separation range. Blunt ultrasound knife was used to separate the posterior part of the kidney to the hilum of the patient to find the position of the renal artery and dissociate it. The renal artery was clamped and severed by HEM-O-LOK. The renal vein was treated in the same way as the renal artery, and then the posterior kidney was dissociated from the retroperitoneum to the anterior kidney. In the treatment of the upper pole of the kidney, first observe whether there is a clear boundary between the adrenal gland and the tumor. If not, the adrenal gland can be removed, and the peripheral adrenal vessels should be carefully treated during the resection. Then dissociate the lower pole of the kidney, separate the gonadal vein and ureteral vein, clamp the gonadal vein, dissociate the renal pedicle, and finally use triple titanium to cut off and clamp. The tissue was removed and sent for pathology. Under the microscope, observe whether there is active bleeding within the operation range, and manage the bleeding point. Finally, a drainage tube was placed and the incision was closed, as shown in Figure 1.

Figure 1

RLRN surgical procedure diagram. (a) Preoperative CT revealed right renal carcinoma. (b) Resection of tumor and surrounding normal renal parenchyma after ultrasonic scalpel dissection. (c) The clamp blocks the renal artery. (d) Resection of tumor and surrounding normal renal parenchyma. (e) After tumor removal.

2.3. Observation Index

The operation time, intraoperative blood loss, postoperative bowel function recovery time, drainage tube indwelling time, hospital stay, and other clinical data were recorded in the two groups. Before operation and 3 months after operation, automatic biochemical analyzer was used to detect blood urea nitrogen (BUN) and blood creatinine (Scr) levels in the two groups, and 99mTc-DTPA renal dynamic imaging was used to determine glomerular filtration rate (GFR). The levels of serum interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were determined by enzyme-linked immunosorbent assay. All patients were followed up for 3–12 months after operation and were divided into two subgroups: recurrence group (n = 12) and nonrecurrence group (n = 94) according to whether they recurred. Record the patient's smoking history, body mass index (BMI), tumor location, tumor diameter, TNM staging, and postoperative immunotherapy. And record whether there are any complications of urine leakage, bleeding, and pulmonary embolism during the follow-up period.

2.4. Statistical Methods

The results of this experiment were statistically analyzed by SPSS 20.0 (SPSS Co., Ltd., Chicago, USA). Count data were expressed by rate, and chi-square test was used for their comparison between groups. Measurement data were expressed by (mean ± standard deviation), and t test was used for their comparison between groups. Multivariate analysis adopts multiple logistic regression model. P < 0.05 indicates that the difference is statistically significant.

3. Results

3.1. Comparison of Relevant Indicators between the Two Groups

The operation time, intraoperative blood loss, postoperative bowel function recovery time, drainage tube indwelling time, and hospital stay in the observation group were lower than those in the control group (P < 0.05), as shown in Figure 2.

Figure 2

Comparison of relevant indicators between the two groups. Note: compared with the control group, P < 0.05.

3.2. Comparison of Renal Function Indexes between the Two Groups

The BUN level after operation was higher than before operation; Scr and GFR levels were lower than before operation (P < 0.05). The BUN level in observation group was lower than control group; Scr and GFR levels were higher than control group (P < 0.05), as shown in Figure 3.

Figure 3

Comparison of renal function indexes between the two groups. Note: compared with before operation, P < 0.05; compared with the control group, #P < 0.05.

3.3. Comparison of Complications between the Two Groups

During the follow-up period, there were 3 cases of urine leakage, 6 cases of bleeding, and 3 cases of pulmonary embolism in the control group, and the total incidence of complications was 22.64% (12/53). In the observation group, there were 1 case of urine leakage and 2 cases of bleeding, and the total incidence of complications was 5.66% (3/53). The total incidence of complications in observation group was lower than that in control group (P < 0.05), as shown in Figure 4.

Figure 4

Comparison of complications between the two groups. Note: compared with the control group, P < 0.05.

3.4. Comparison of the Levels of Inflammatory Factors between the Two Groups

After operation, the levels of serum IL-6 and TNF-α in 2 groups were higher than those before operation, and the observation group was lower than the control group (P < 0.05), as shown in Figure 5.

Figure 5

Comparison of the levels of inflammatory factors between the two groups. Note: compared with before operation, P < 0.05; compared with the control group, #P < 0.05.

3.5. Single Factor Analysis Affecting the Recurrence of Renal Cancer after Surgery

Univariate analysis showed that age, smoking history, tumor diameter, TNM staging, surgical methods, and postoperative immunotherapy were related to postoperative renal cancer recurrence (P < 0.05), as shown in Table 2.

Table 2

Single factor analysis affecting the recurrence of renal cancer after surgery.

Factors	n	Recurrence group (n = 12)	Nonrecurrence group (n = 94)	χ 2	P
Gender				1.068	0.301
Male	65	9 (75.00)	56 (59.57)
Female	41	3 (25.00)	38 (40.43)
Age (years)				4.835	0.038
≥60	48	9 (75.00)	39 (41.49)
<60	58	3 (25.00)	55 (58.15)
Smoking history				5.783	0.016
Yes	24	6 (50.00)	18 (19.15)
No	82	6 (50.00)	76 (80.85)
BMI (kg/m2)				0.098	0.934
≥24	63	7 (58.33)	56 (59.57)
<24	43	5 (41.67)	38 (40.43)
Tumor location				0.185	0.846
Left	65	7 (58.33)	58 (61.70)
Right	41	5 (41.67)	36 (38.30)
Tumor diameter (cm)				5.589	0.018
≥5	38	8 (66.67)	30 (31.91)
<5	68	4 (33.33)	64 (68.09)
TNM staging				7.763	0.005
≤T2	85	6 (50.00)	79 (84.04)
>T2	21	6 (50.00)	15 (15.96)
Surgical methods				4.025	0.048
RLRN	53	3 (25.00)	50 (53.19)
ORN	53	9 (75.00)	44 (46.81)
Postoperative immunotherapy				5.086	0.024
Yes	74	5 (41.67)	69 (73.40)
No	32	7 (58.33)	25 (26.60)

3.6. Analysis of Multiple Factors Influencing the Recurrence of Renal Cell Carcinoma after Operation

Multivariate logistic analysis showed that age, tumor diameter, TNM staging, surgical methods, and postoperative immunotherapy were independent influencing factors of postoperative renal cancer recurrence (P < 0.05), as shown in Tables 3 and 4.

Table 3

Assignment for multivariate analysis of factors.

Factors	Variable	Assignment
Age	X1	<60 = 0, ≥60 = 1
Smoking history	X2	No = 0, Yes = 1
Tumor diameter	X3	<5 = 0, ≥5 = 1
TNM staging	X4	≤T2 = 0, >T2 = 1
Surgical methods	X5	RLRN = 0, ORN = 1
Postoperative immunotherapy	X6	Yes = 0, No = 1

Table 4

Analysis of multiple factors influencing the recurrence of renal cell carcinoma after operation.

Variables	B	SE	Walds	P	OR	95% CI
Age	0.952	0.315	4.302	0.043	2.591	1.358∼3.692
Smoking history	0.318	0.149	1.759	0.235	1.374	0.875∼1.903
Tumor diameter	1.152	0.476	5.032	0.033	3.165	2.158∼4.226
TNM staging	1.306	0.412	5.863	0.026	3.691	1.284∼5.843
Surgical methods	1.022	0.398	4.236	0.044	2.779	1.482∼3.891
Postoperative immunotherapy	1.126	0.457	4.894	0.038	3.083	1.945∼4.263

4. Discussion

Renal cancer is one of the common malignant tumors in the urinary system. Surgical treatment is currently the main clinical treatment for renal cancer patients [14, 15]. At present, for the treatment of kidney cancer, in the case of patients with no obvious surgical contraindications, the first choice is surgical treatment, radical nephrectomy, with good surgical effect, which is recognized as a cure for kidney cancer [16, 17]. With the continuous innovation of laparoscopic equipment and laparoscopic operating instruments, laparoscopic radical nephrectomy has gradually become the mainstream surgical method for the treatment of renal cancer, which has been carried out more and more widely. Laparoscopic radical nephrectomy is divided into retroperitoneal approach and peritoneal approach. Clinical studies have proved that there is no significant difference in efficacy between the two approaches, which is related to the proficiency of the operator in the operation [18, 19]. Because ORN has a large wound, there are more tissues in the abdominal cavity that need to be separated during operation, which can easily cause damage and pollution to other organs in the abdominal cavity, which seriously affects the prognostic effect of patients [20, 21]. With the development of laparoscopic technology, RLRN has the advantages of less trauma, less bleeding, and faster recovery and has gradually replaced ORN. However, surgery can only control tumors in the kidney; some patients have cancer cells that have entered the blood or lymphatic system. Radical surgery cannot eliminate these escaped cancer cells, which leads to recurrence [22, 23]. Therefore, it is extremely important to explore the related factors that affect the recurrence of renal cancer and to prevent and treat them.

Gill et al. [24] studied 136 patients who underwent laparoscopic nephrectomy (133 patients underwent laparoscopic radical nephrectomy and 3 patients underwent laparoscopic partial nephrectomy without lymphadenectomy) and followed them for 1 to 10 years. The results showed that the incidence of implantation metastasis was 1.47%, and RLRN did not necessarily increase the incidence of implantation metastasis, suggesting that retrolaparoscopic radical nephrectomy brought fewer complications and higher safety. The results of this study showed that the operation time, intraoperative blood loss, postoperative bowel function recovery time, drainage tube indwelling time, and hospital stay in the observation group were lower than those in the control group. The postoperative BUN levels of the two groups were higher than those before the operation, the Scr and GFR levels were lower than those before the operation, the BUN levels of the observation group were lower than the control group, and the Scr and GFR levels were higher than the control group. Gill's [25] study found that, compared with open radical nephrectomy, retrolaparoscopic radical nephrectomy had obvious advantages in reducing intraoperative blood loss, postoperative hospital stay, analgesic need, and time for bowel function recovery, which was consistent with the results of this study. These results suggest that retrolaparoscopic radical nephrectomy, as one of the minimally invasive operations, can achieve the same clinical effect as open radical nephrectomy in the clinical treatment of localized renal cancer. In addition, RLRN is used to treat renal cancer patients with short operation time, less trauma, and fast postoperative recovery and can effectively alleviate the renal function injury of patients. The reason is that ORN mainly ligates the renal artery, renal vein, and ureter of patients and then dissociates the kidney, so as to avoid the implantation metastasis of tumor cells in patients, reduce the recurrence rate, and ensure the surgical efficacy. RLRN has smaller surgical incision, less postoperative pain, and less impact on gastrointestinal function of patients, which can help patients recover gastrointestinal function at an early stage, shorten postoperative feeding time of patients, and enable patients to get out of bed and exercise as soon as possible. Moreover, RLRN has less trauma, clear surgical approach, no need for incision of the peritoneum, and less separated abdominal tissues, which can avoid long-term exposure of abdominal organs, effectively improve the injury and pollution of other abdominal organs, and contribute to postoperative recovery [26, 27]. The results of this study showed that the total incidence of postoperative complications in the observation group was lower than that in the control group, and the levels of serum IL-6 and TNF-α were lower than those in the control group. These results indicate that RLRN can effectively reduce the incidence of complications in patients with renal cancer and reduce the inflammatory response of the body.

The results of this study showed that univariate analysis showed that age, smoking history, tumor diameter, TNM staging, surgical methods, and postoperative immunotherapy are related to postoperative renal cancer recurrence. Multivariate logistic analysis showed that age, tumor diameter, TNM staging, surgical methods, and postoperative immunotherapy are independent influencing factors for postoperative renal cancer recurrence. Analysis of the reasons is that the elderly have less knowledge about diseases and less attention, coupled with the decline of their body functions year by year and the weakening of their own immune system function, which can not effectively inhibit tumor metastasis and recurrence. Patients with large tumor diameters and high TNM stages mean their tumor proliferation ability is strong. The renal function is poor, which seriously affects its prognostic effect and can easily cause tumor recurrence. Postoperative combined radiotherapy, chemotherapy, and other adjuvant treatments can effectively improve the prognosis of patients and reduce the risk of recurrence.

Through repeated surgical operations, postoperative discussion, and summary of intraoperative experience, physicians in our department believe that, during endoscopic operation, the surgeon should be familiar with the anatomical structure of the urinary system and be able to skillfully operate various endovascular instruments and strictly grasp the indications and contraindications of the operation; the establishment of the retroperitoneal cavity during the operation is the key to ensure the successful completion of the operation. The posterior abdominal cavity should be established between the transverse abdominal fascia and the extrarenal fascia peritoneal tissue. During the operation, fully exposing the renal pedicle and handling it is the key to the operation. The operation of the free blood vessel needs to be gentle and careful to ensure the smooth progress of the operation. RLRN requires complete resection, so attention should be paid to the marking of anatomical sites, such as adrenal gland, psoas major muscle, and extraperitoneal fat. Proper management of renal pedicle vessels is also the key to successful operation. Early treatment of renal arteries and veins during the operation can not only reduce bleeding, but also avoid the tumor being squeezed and spread through veins. Compared with the peritoneal route, the retroperitoneal route is easier to expose the renal hilum and treat the blood vessels earlier. Arteries are usually clipped and cut off before veins are treated. Hem-o-lok can be used when clamping blood vessels, which is safe and easy to operate. For most doctors, the identification of renal arteries is not a problem, but it is necessary to pay attention to whether there are multiple arteries. If the missing artery is left untreated, the renal vein will be clamped to rapidly increase the volume of the kidney and reduce the operation space, which will bring great trouble to the operation, especially those who adopt the retroperitoneal route. Therefore, it is necessary to read the CT film carefully before operation to determine whether the renal artery is multivessel. After the renal artery is clamped during the operation, it can be observed whether the renal vein collapses. If there is no collapse, it is considered that there is an ectopic artery untreated. For T1b tumors, renal blood flow should be effectively blocked according to the results of CTA to avoid the blockage of missed branches, so as to ensure a relatively clear visual field during tumor resection. The second is the use of the attractor. After cutting the renal parenchyma outside the tumor, the attractor is inserted through the auxiliary channel and adjusted to 1/3 to 1/2 of the maximum opening volume, which can be adjusted to the maximum attraction volume during open surgery. The assistant will continue to attract the surgeon to cut the area and keep the surgical field clear. The continuous suture of barbed wire is used for hemostasis of small blood vessel broken end, repair of collecting system, and suture of renal parenchyma without knotting, which can obviously shorten the ischemia time.

5. Conclusion

RLRN treatment of renal cancer patients has a short operation time, less trauma, quick recovery after surgery, and fewer complications and can effectively alleviate the renal function injury and the body's inflammatory response, which is worthy of promotion. The postoperative recurrence is related to age, tumor diameter, TNM stage, surgical method, and postoperative immunotherapy.