2020年 · 第35卷第06期

Retroperitoneal tumors refer to tumors (except tumors of retroperitoneal organs) located below the transverse diaphragm and above the pelvic diaphragm, and in the potential space behind the visceral peritoneum. The incidence rate accounts for less than 0.5% of all kinds of tumors in the whole body. However, in recent years, its incidence rate has increased significantly and shows a younger trend. There are about 70 pathological types of retroperitoneal tumors, benign, borderline and malignant types are many and complex, among which malignant retroperitoneal sarcoma (RPS) accounts for about 80%. This type of tumor is deep in location and hidden in onset. It is often discovered when the tumor is huge, invades or squeezes the surrounding organs and complications occur. It is difficult to completely radically remove malignant patients by surgery, and the recurrence rate after surgery is high. Most of them are insensitive to radiotherapy and chemotherapy, which has become a common challenge faced by the world in the current field of oncology. The emphasis on retroperitoneal tumor in China and Western countries began in 1990s, and it has achieved rapid development. At present, the research status of this field in surgical circles in China is still insufficient, and its future development is still hesitant. This article focuses on the history of retroperitoneal tumor surgery, and discusses the future development of retroperitoneal tumor diagnosis and treatment in China.

Soft tissue sarcomas are a rare disease with an incidence rate of only 1% of all solid tumors, but they contain about 50 pathological types with strong histological and biological behavioral heterogeneity. According to the anatomical location, about 15% ~20% of soft tissue sarcomas occur in the retroperitoneal space. Special anatomical structure and often large tumor volume are the main reasons that lead to the difficulty of treatment, high recurrence rate and poor prognosis of retroperitoneal sarcomas^[1]。 As the most common pathological type of retroperitoneal sarcoma, liposarcoma is insensitive to conventional radiotherapy and chemotherapy. Radical surgical resection is still the only possible cure at present, but the overall efficacy is not good for a long time. Combined with the development history and current situation of retroperitoneal tumor surgery, this paper expounds the controversial hot issues in the surgical treatment of retroperitoneal liposarcoma.

A 66-year-old female was seen for "palpable mass in the right lower abdomen for 1 week". She reported a past history of vertigo and denied a history of hypertension. Physical examination: blood pressure 117/69 mmHg. A huge mass can be palpable in the right lower abdomen, which is tough in texture, without tenderness, with clear borders and acceptable mobility. There were no abnormalities in serum tumor markers. CT examination showed: huge abnormal density shadow in the right lower abdomen, obvious margin enhancement in the arterial phase, and weakened margin enhancement in the venous phase and delayed phase, considering ovarian-derived tumor (Figure 1)。 Surgical exploration: The mass was located retroperitoneally at the ileocolic mesenteric, 15 cm ×10 cm ×10 cm in size, immediately adjacent to the ascending colon, duodenum and right ovary. Complete excision of the tumor (Figure 2)。 Blood pressure fluctuation: 115/65 mmHg before operation, 125/70 mmHg during operation, and 195/110 mmHg after operation. Antihypertensive treatment was given, and blood pressure returned to normal after 2 days. Pathological diagnosis: paraganglioma. Under the light microscope, the capsule was involved (Figure 3)。 Immunohistochemical staining: positive for chromaffin, positive for synaptophysin and positive for S-100 protein.

A 68-year-old male was admitted for "anal pain during defecation with bloody stool for 2 years". One year ago, I went to a primary hospital for hemorrhoid surgery with "mixed hemorrhoids". Postoperative anal pain, occasional bleeding, accompanied by laborious defecation. Specialist physical examination showed that the surgical wound at the anal opening was not healed, with scaly plaques on the surface with ulcers, raised edges and clear boundaries (Figure 1), there was a mass in the anal canal palpable by the finger diagnosis, 2.0 cm ×1.5 cm in size and soft in texture. Colonoscopy revealed: anal mass. Pathological biopsy showed: anal eczema-like carcinoma (FIG. 2A)。 AR (individual cells +), CK5/6 (−), CK7 (±), GCDFP-15 (−), Ki-67 (mid-surface cells scattered +). Local enlarged resection of perianal mass and flap transplantation were performed under spinal anesthesia. Postoperative pathological examination showed: (anal eczema-like carcinoma) Paget's disease with mucinous adenocarcinoma, infiltration into subcutaneous fibrous fat, intravascular tumor thrombus (-), nerve invasion (-), basal margin (-), horizontal margin (-), muscle involvement (-) (Figure 2B)。

A 66-year-old male was seen for "upper abdominal distension and pain, acid reflux and belching for more than half a month". Enhanced CT examination showed that the gastric antrum occupied space, and malignancy was not excluded. Gastroscopy revealed that there were bulging lesions in the gastric antrum, congestion and edema on the surface, and apical ulceration. Endoscopic ultrasound revealed that there was a mixed echo mass in the wall of the gastric antrum, the section size was about 3.5 cm ×4.0 cm, and the blood supply around the lesion was abundant (Figure 1)。 Reexamination and enhanced CT showed that the stomach pyloric sinus wall was thickened, the small curve side was marked, the enhanced scan was uneven enhancement, the localized enhancement of the small curve side was reduced, and several small lymph nodes were mildly enhanced around the gastric antrum (Figure 2)。 Preoperative diagnosis: The possibility of gastric stromal tumor is large. Single-port laparoscopic distal gastrectomy was performed. Intraoperative exploration showed that there were no nodules on the surface of the abdominopelvic cavity, omentum and liver, and the small curved side of the gastric antrum was raised and local stiffness. The posterior wall of the gastric antrum was densely adhered to the pancreas, and the duodenum was severed with ENDO-GIA 2 cm below the pylorus. The stomach was cut and closed about 6 cm above the lesion, and the specimen was removed through the umbilical incision. After dissection, a mass in the posterior wall of the gastric antrum was found, about 4 cm ×3 cm in size, and the central area was partially necrotic. One fish bone with a length of about 3 cm and a maximum diameter of about 0.2 cm was seen (Figure 3), the frozen pathological examination results suggest: inflammatory lesions. The gastrointestinal reconstruction was performed by Billroth II method under laparoscope. Postoperative pathological examination revealed distal gastric inflammatory lesions with abscess and ulcer formation and reactive lymph node hyperplasia.

A 62-year-old male underwent colonoscopy in January 2019 due to "intermittent hematochezia", which showed that a cauliflower-like mass blocked the intestinal lumen about 14 cm away from the anal margin, and the intestinal lumen was obviously narrowed. Pathological biopsy showed moderately-poorly differentiated adenocarcinoma. Pelvic MRI showed that rectosigmoid junction cancer (T₂N₂M_X)。 After 3 cycles of neoadjuvant chemotherapy with oxaliplatin combined with capecitabine, the drug was discontinued for 5 weeks, and he was admitted to our hospital for surgical treatment. Right indirect inguinal hernia was discovered 2 months ago. Physical examination: In the standing position, the patient saw a reducible mass about 5.0 cm ×3.0 cm in size in the right inguinal area, which could be lowered to the scrotum, and the mass disappeared after lying down. Preoperative colonoscopy showed a mucosal lesion about 13 cm away from the anal margin. The surface mucosa was rough and locally nodular, with a size of about 2.5 cm ×3.0 cm. Preoperative diagnosis: right indirect inguinal hernia after neoadjuvant chemotherapy for rectal cancer. Laparoscopic radical rectal cancer surgery and hernia repair were performed simultaneously. Trocar was placed according to the conventional position of laparoscopic radical rectal cancer resection, that is, 10, 5, 12, 5 and 5 mm Trocar was placed on the umbilicus, right upper abdomen, right lower abdomen, left upper abdomen and left lower abdomen, respectively. Routine exploration showed that the lesion was located in the upper rectum, 3 cm above the peritoneal reflex, and a local defect was seen in the right inguinal area, about 2 cm wide. Hernia repair was performed first. Because the patient underwent rectal cancer surgery at the same time, it was not appropriate to use a patch. Observing the width of the medial umbilical fold, hernia repair was completed with his own tissue. The right medial umbilical fold was separated from the inferior umbilicus along the anterior abdominal wall from the cephalic side to the caudal side, and a rectangular peritoneal flap of about (5~7) cm × (2~3) cm was made (Figure 1), and then annularly incise the outer edge of the inner annulus (Figure 2), turning the free medial umbilical fold flap laterally about 90 degrees, and packing it into the inguinal canal (Figure 3), and finally, the medial umbilical fold flap was continuously sutured and fixed with the peritoneum at the inner ring incision with 3-0 absorbable barb thread, and the incision of the free fold flap was closed (Figure 4)。 Laparoscopic radical resection of rectal cancer was followed. The patient recovered well after surgery, and there was no recurrence of the hernia since the follow-up.

A 29-year-old woman was admitted for "abdominal pain with vomiting for 4 d". He has a history of repeated melena, blood transfusion and cesarean section in the past. In June 2018, he underwent gastric mucosal hemangioma excision under gastroscopy. Physical examination: The abdomen was flat, and an old surgical scar about 6 cm long was visible in the lower abdomen. Soft abdomen, obvious periumbilical tenderness, no rebound pain, negative mobile voicing, and bowel sounds 7 times/min. Routine blood test: Hb 96 g/L. Total abdominal CT examination showed that: (1) the possibility of right lower abdominal intussusception (ileum into colon) was high; (2) Multiple intrahepatic hemangiomas; (3) Pelvic effusion. Exploratory laparotomy was performed, and a small amount of fluid in the abdominal cavity was seen during the operation, and the terminal ileum was inserted into the ascending colon. After manual reduction during the operation, two hemangiomas with a size of about 3 cm ×3 cm in the ileocecal region and 5 cm from the ileocecal region distal to the ascending colon were seen (Figure 1), tough in texture, without breaking through the serosa; Multiple hemangiomas in the jejunum and ileum below 15 cm from Treitz's ligament, with different sizes, one separated by about 10 cm, and local multiple hemangiomas clustered; Multiple hemangiomas on the surface of the liver can be seen. Diagnosis: Multiple intestinal hemangioma with intussusception; Hepatic hemangioma. Because hemangioma is distributed in multiple intestinal segments of jejunoileum, in order to avoid short bowel syndrome caused by excessive resection of intestinal tubes, palliative right hemicolectomy + partial ileectomy + suture of intestinal hemangioma root to stop hemorrhage was performed. Postoperative pathological report: A mucosal bulge with a size of 2 cm ×1.7 cm ×1 cm was seen 5.5 cm from the ileal incision, and the incision surface was gray-red; See also multiple gray-red areas in 8 cm mucosa of partial free intestinal tube. Under light microscope, vascular cluster hyperplasia was observed between mucosa and muscle wall. The pathological diagnosis was cavernous hemangioma. The patient recovered and was discharged after surgery. Since the follow-up after surgery, the patient has no symptoms such as bloody stool or melena.

A 26-year-old male was admitted to hospital for "intermittent abdominal distension for more than 10 years". Physical examination: abdominal swelling, positive left upper abdominal tenderness, no rebound pain, muscle tension, positive abdominal tremor and mobile voiced sound, and intestinal sound about 10 times/min. Examination of the knee-thoracic position: digital rectal diagnosis of anal sphincter relaxation. Barium enema X-ray examination showed that a huge downward capsular bag shadow was seen in the splenic flexure of the colon to the small pelvic cavity, and a large amount of intestinal content was retained in it. Barium entered the capsular bag along this opening, which was about 4 cm wide, and more barium was retained after barium discharge. Enhanced CT examination of the abdomen showed that the local intestinal canal of the splenic flexure of the colon was sac-like dilation, occupying most of the abdominal cavity. Colonic duplication malformation was diagnosed. Exploration of epigastric median incision was performed. During the operation, a malformed intestinal tube, about 25 cm long, opened downward from the splenic flexure of the colon in the transverse mesocolon was seen. This segment of malformed intestine was surgically removed, and the resection range was 2~3 cm normal intestine, and end-to-end colonic anastomosis was performed (Figure 1)。 The intestinal tube submitted for examination was 30 cm long, one end was blind, and part of the intestinal tube was dilated and the mucosal folds disappeared. Under light microscope, chronic inflammation of intestinal wall mucosa accompanied by congestion and dilation of submucosal blood vessels, and mild to moderate atypical hyperplasia in some mucosa. After six months of follow-up, the symptoms of abdominal distension and constipation improved.

A 46-year-old male was seen mainly for "11 months after subtotal gastrectomy, vomiting feces for more than 1 month". On February 15, 2017, the patient underwent "subtotal gastrectomy (Roux-en-Y operation)" in an external hospital due to "gastric ulcer and perforation", and the patient recovered well after operation. In mid-July 2017, the patient experienced abdominal distension, nausea, and vomiting. The vomit was a yellow fecal substance with malodor, and he vomited several times a day, each time with an amount of about 100 ml. In mid-August 2017, the patient felt numbness and weakness in both lower limbs, accompanied by pain in both lower limbs and unable to stand. On August 22, 2017, X-ray angiography of the upper gastrointestinal tract was performed in the outpatient department of our hospital, which showed that a large amount of fasting retention fluid was visible in the residual stomach, and the residual stomach-jejunal anastomosis was not unobstructed. After changing body position, contrast medium could be seen entering the distal intestinal tube (Figure 1)。 Complete abdominal CT scan showed that contrast medium filling was visible in the residual stomach, distal jejunum and transverse node field (Figure 2)。 Gastroscopy showed that there were more yellow-green fecal substances in the residual gastric cavity, and the anastomosis was medium-sized. When entering the anastomosis, one side was left open, and one double channel was seen on the other side, all of which were unobstructed, and a large amount of feces was seen in one channel. Considering that the patient had gastrocolic fistula, poor nutritional status, and temporarily unable to tolerate surgical treatment, small intestinal nutrition tube placement was performed. After the patient's nutritional status improved, a distal gastrectomy + partial colectomy was performed on January 5, 2018. During the operation, the gastrointestinal anastomosis was severe adhered and communicated with the transverse colon, forming a gastrocolic fistula. After discharge, the patient did not take acid suppressant drugs and developed hematemesis and hematochezia on 5 November 2018. Emergency gastroscopy: 2 ulcers, about 1.0~1.2 cm in diameter, covered with white coating, were seen in the anastomosis, and a vascular stump was seen in one of the ulcers with active bleeding. Gastroscopic hemostasis was performed.

The patient was a 29-year-old female. Admitted for "3 weeks with left lower abdominal mass found". Physical examination: a mass can be palpable in the left lower abdomen, and the border cannot be palpable, accompanied by mild tenderness. CT examination showed that low-density shadows with a size of about 89 mm ×59 mm ×124 mm were visible in the pelvic cavity, with clear boundaries. After enhancement scan, progressive heterogeneous mild enhancement was visible, and multiple patch-like and septal-like enhancements were observed in the mass (Figure 1)。 Laparoscopic tumor resection was performed. During the operation, it was found that the tumor was located behind the peritoneum, and it showed expansive growth behind the junction of the left peritoneum and the sigmoid colon visceral peritoneum, with an intact capsule, smooth surface, and external pressure on the left ureter (Figure 2)。 The gross postoperative specimens were oval in shape, about 130 mm ×80 mm in size, with smooth surface, enveloped, tough texture, gray-white cross section with edema (Figure 3)。 Postoperative pathological examination revealed: spindle cell tumor, considered leiomyoma, with edema and degeneration, intact capsule (Figure 4)。 Immunohistochemical staining results: Desmin (+), SMA (+), Actin (+), CD34 (-), CD117 (-), ER (+), PR (+), Ki67 (+)<5%, S-100 (−). No tumor recurrence was observed after 6 months follow-up.