Peritoneal metastases
Introduction
Introduction to peritoneal metastases Peritoneal metastatic cancer (peritoneal metastatic carcinoma) is more common in clinical cancer, which is caused by peritoneal metastasis of blood cells or direct peritoneal growth. More secondary to the intra-abdominal liver, stomach, colon, pancreas and ovary, uterus cancer and retroperitoneal malignant tumors, can also be secondary to the lungs, brain, bones, nasopharynx tumors and skin melanoma. basic knowledge Sickness ratio: 0.0004%-0.0006% Susceptible people: no special people Mode of infection: non-infectious Complications: volvulus, intussusception, jaundice
Cause
Cause of peritoneal metastasis
(1) Causes of the disease
The main site of the disease is the intra-abdominal organs, with ovarian cancer and pancreatic cancer, followed by the stomach, uterus, colon and lymphatic system. Extraperitoneal lung cancer and breast cancer can also be transferred to the peritoneum. 30% of leukemia patients may have peritoneal involvement. The presence of free cancer cells and residual microscopic lesions in the peritoneal cavity is a key factor in postoperative recurrence and peritoneal metastasis of intra-abdominal malignant tumors. It has a strong ability to regenerate and is easily implanted on the peritoneal surface of surgical anatomical lesions, under the exposed mesothelium. Connective tissue, which causes local recurrence and metastasis after surgery, the sources of free cells in the abdominal cavity are:
1. Tumor cells infiltrate the peritoneal organ serosal membrane and directly fall into the abdominal cavity. The positive rate is proportional to the biological characteristics of the tumor and the area of serosal infiltration.
2. Intraoperatively not properly isolated, cancer cells falling into the gastrointestinal cavity flow into the abdominal cavity with the gastrointestinal fluid through the stump.
3. The tumor thrombus in the surgical region is severed and the lymphatic fluid flows into the abdominal cavity with blood flow and lymph.
The microscopic lesions remaining in the abdominal cavity include: small tumors that cannot be completely removed by surgery; the cancer cells in the abdominal cavity are solidified by the cellulose in the surgical area to form a protective layer, which makes it difficult to be swallowed by immune cells, forming a residual small cancerous foci. Complications such as surgery and anesthesia, the body's immunity is reduced, cancer cells proliferate, and a mass is formed, eventually leading to local recurrence and metastasis of the abdominal cavity.
In addition, in the clinic, there may be cases of abdominal metastatic tumors of unknown origin. Although various examinations are still difficult to determine the primary lesions.
(two) pathogenesis
Abdominal metastatic tumors can be secondary to different tissues of various organs and systems throughout the body. The common metastasis methods are: extra-abdominal or intra-abdominal visceral tumors undergoing blood transfer, lymphatic metastasis; intra-abdominal organs, abdominal wall tumors directly Implantation, infiltration and metastasis, among which, laparoscopic surgery or laparotomy, tumor resection is a more common and important mode of metastasis in clinical practice.
More than 75% of peritoneal metastases are metastatic adenocarcinomas (Fig. 1). After the tumors of the abdominal organs involve the serosa, the tumor cells fall off, diffusely implanted on the peritoneum, the surface of the omentum or mesentery, grow and multiply, and connect with the peritoneum. The tissue is surrounded by metastatic nodules of varying sizes. The nodules can be rice-like, nodular, and peritoneal metastases often cause extensive adhesion of bloody ascites and organs, leading to death.
Prevention
Peritoneal metastasis cancer prevention
The prevention of metastatic tumors of the abdominal cavity mainly depends on surgery. Laparoscopic surgery is strictly in accordance with the requirements of surgical tumor-free techniques for prevention. At the same time, continuous intraperitoneal hyperthermic perfusion chemotherapy can be applied, and for tumors derived from extra-abdominal organs, In clinical examination, it is necessary to reduce the squeezing and prevent blood and lymphatic metastasis, especially in the invasive puncture examination and endoscopy under the guidance of B-ultrasound, CT, etc., to grasp the indications, gentle operation, and prevent iatrogenic transfer. Of course, early diagnosis and early treatment of various types of cancer patients are the most important preventive measures.
Complication
Peritoneal metastasis Complications, volvulus, intussusception, jaundice
If the tumor invades the liver or bile duct, it may have jaundice. When the tumor compresses the gastrointestinal tract or the intestine is twisted due to the mass, the intussusception may cause pain, vomiting, swelling, and closing of the intestinal obstruction.
Symptom
Peritoneal metastasis of cancer symptoms Common symptoms Diffuse abdominal ossification ascites Abdominal mass nausea Weight loss Abdominal pain Appetite weakness Grayish nodules Abdominal midline lumps
Abdominal metastatic tumors have different manifestations due to their origin and tumor pathological properties. In addition to the performance of primary tumors, peritoneal metastases are mainly characterized by ascites, bloating, abdominal pain, anemia and weight loss. The common manifestations are:
1. Abdominal distension and ascites ascites are the most common and early clinical symptoms of abdominal metastatic tumors. The amount of ascites is often small, which is different from severe abdominal distension caused by massive ascites in patients with cirrhosis, tuberculous peritonitis and nephropathy. At the same time, accompanied by portal vein metastasis or liver metastasis, it can also be expressed as a large amount of ascites. Physical examination can reveal mobile dullness. Ascites is often a colorless or light yellow micro-mixed liquid. If it is accompanied by tumor necrosis, it can be bloody. Exudate, high protein content, ascites pathological examination can find tumor cells.
2. Abdominal mass caused by abdominal cavity metastasis of the abdomen is often multiple, can be located in various areas of the abdomen, often have a certain degree of activity, the activity varies depending on the different parts of the peritoneum of the tumor, the texture of the tumor due to the pathological nature of the tumor Different, sometimes the tumor invades the abdominal wall and can be expressed as a fixed mass of the abdominal wall. The texture is often hard and the tenderness is obvious.
3. Digestive symptoms often manifest as loss of appetite, sometimes accompanied by nausea, vomiting, abdominal pain and diarrhea. If the tumor invades the liver or bile duct, it may have jaundice. When the mass compresses the gastrointestinal tract or the intestine is twisted due to the mass, the intussusception , there may be pain, vomiting, swelling, and closing symptoms of intestinal obstruction, and some patients have a clear diagnosis due to acute intestinal obstruction surgery.
4. Systemic symptoms often manifested as fatigue, weight loss, anemia, cachexia.
5. The symptoms of the primary disease vary according to different tissues, organ sources and different pathological types. For example, patients with gastric cancer may have upper gastrointestinal bleeding and pyloric obstruction; patients with liver cancer may have jaundice, liver failure, portal hypertension, and abdominal external organs. The peritoneal metastasis of the device is often based on the primary lesions, and even the more obvious symptoms of abdominal metastasis are mistaken for the performance of the primary tumor and the treatment is abandoned. Very few patients are clearly identified as abdominal metastatic tumors or abdominal metastasis at autopsy. It is not possible to determine the source of the primary lesion.
Examine
Examination of peritoneal metastases
Laboratory inspection
The general test of this disease often manifests as the characteristics of the primary tumor. For example, patients with liver cancer may have elevated AFP. Patients with colorectal cancer may have elevated CEA, and fecal occult blood is positive with gastrointestinal bleeding. Some cases may have anemia. Tumors in obstetrics and gynecology have endocrine abnormalities.
1. Cytological examination of the ascites by abdominal aspiration for cytological examination, the positive rate of detection is 50% ~ 80%, the following 3 points can improve the detection rate of ascites cancer cells: 1 repeated search; 2 draw enough ascites At least 500ml; 3 let the patient turn over several times before taking ascites, so that the precipitated cancer cells are more easily extracted.
2. Biopsy biopsy under direct vision is the most accurate method of examination.
3. Blood routine and plasma proteins may have red blood cells, reduced hemoglobin and decreased plasma albumin.
4. Ascites examination Abdominal puncture ascites examination is the simplest, rapid, convenient, less damage clinical examination method, for patients with clinically suspected abdominal metastatic tumors can be repeated, through the examination of ascites exfoliated cells to confirm the diagnosis, and according to the tumor The characteristics of pathological types are traced to the primary lesion.
In conclusion, biopsy is the most reliable method for diagnosing this disease. Biopsy specimens can be obtained by abdominal puncture, laparoscopic or laparotomy, and only for diagnostic laparotomy for obtaining living tissue, and most living tissues Specimens were obtained during therapeutic surgery.
Film degree exam
1.B-ultrasound
(1) Ascites: common ascites and abdominal organs adhesion, the sound image shows the free echo zone in the abdominal cavity, and the intestinal tube adheres to the posterior abdomen.
(2) irregular thickening of the peritoneum: the sonogram shows that the thickened peritoneum has a high echo band-like change, and the shape is often irregular.
(3) intra-abdominal tumor nodules: intra-abdominal tumor nodules often with ascites and clear, more common in the right abdominal wall and pelvic wall, can also be located in the middle of the upper abdomen, the nodule and abdominal wall boundary is unclear, protruding into the abdominal wall Those who do not have ascites can see solid, cystic or mixed mass echoes, and some tumors can show the primary tumor image and multiple lymph nodes in the peritoneal mesentery.
2. CT scan
It can show the location, size, nature and ascites of metastatic cancer. It has great value in the diagnosis of this disease. It can be located and understand the number, texture, blood supply of the tumor, and help to find the primary lesion.
The CT findings of peritoneal metastatic tumors were ascites, wall peritoneal thickening, mesenteric and omental fouling, nodular, cake-like and mass-like changes, intraperitoneal cystic mass change, small intestine wall thickening and small intestine Shift, many authors believe that CT can be the preferred method of examination for peritoneal metastatic tumors.
(1) Ascites: a uniform water density between abdominal organs (Fig. 5A). A small amount of ascites accumulates in the liver or kidney crypt or the lateral edge of the liver. When there is a large amount of ascites, it surrounds the entire abdominal organ and can enter the small omental sac. Inside.
(2) irregular thickening of the peritoneum: under normal circumstances, CT generally does not show the anterior wall peritoneum, the posterior wall peritoneum only shows a thin line of pencil-like appearance, but the peritoneum of the abdominal metastatic tumor can be broad-banded, nodules Shaped or massive, with a wide band shape, followed by nodular shape, which may be related to the growth and fusion process after the majority of tumor cells are planted, and the broadband tumor may be a manifestation of nodule fusion, at the site, to the right The lateral abdominal wall is more common, followed by the left abdominal wall and the anterior abdominal wall.
(3) Mesenteric and omental changes:
1 dirt-like change: in the mesenteric or omentum of uniform fat density in normal times, most of the fine spots and short strips of dirt-like density appear in the region.
2 nodular changes: nodular soft tissue density in the mesentery or omentum of fat density.
3 cake-like omentum or mesentery: the omental or mesentery loses fat density and is replaced by the soft tissue density of the cake.
The above three manifestations can exist at the same time, and the fine-skinned omentum or mesentery can be enlarged into nodules and then fused into a cake.
(4) changes in polycystic or monocystic space in the abdominal cavity: manifested as multiple or single cystic changes in the abdominal cavity, thin capsule wall, water density in the capsule, and a mass effect, which can be compared with simple ascites Identification.
(5) thickening of the small mesenteric wall: manifested as thickening of the small intestine wall, with the mesenteric margin as the part, involving most or most of the intestinal wall. The diagnosis of peritoneal metastatic tumors needs to be combined with the patient's primary disease history and typical CT findings, and should be differentiated from peritoneal tuberculosis and primary peritoneal tumors, because the CT signs of the three have a large overlap.
3. MRI peritoneal metastasis can be directly spread along the mesenteric surface, intraperitoneal implantation, hematogenous metastasis and lymphatic metastasis. Enhanced fat suppression can show that the blocky peritoneal metastasis lesions are obviously strengthened, the border is generally not smooth, intraperitoneal implantation The metastatic lesions showed multiple scattered nodule enhancement lesions.
4. X-ray examination for the diagnosis of this disease, can be used for gastrointestinal barium meal and barium enema, some patients can see indirect signs of gastrointestinal pressure and displacement, if the tumor originated in the gastrointestinal tract The primary lesion can be found. The selective angiography sometimes shows the neovascularization of the tumor, but there is no special sign for the diagnosis of the disease. B-ultrasound often has a positive finding on the abdominal examination, which can show multiple substantial masses, occasionally cystic. Change, at the same time visible ascites, if necessary, can be guided by B-ultrasound fine needle aspiration biopsy to confirm the diagnosis and pathological type.
5. Laparoscopy for patients with unexplained abdominal mass with obvious ascites, can be examined by laparoscopy, after aspirating ascites, there are many lumps or nodules in the parietal and visceral peritoneum, with laparoscopic nodules or Tumor biopsy is a very effective method to determine the diagnosis of tumor metastasis in the abdominal cavity.
Diagnosis
Diagnosis and differentiation of peritoneal metastatic carcinoma
Diagnostic criteria
For patients with abdominal metastasis after malignant tumor surgery, the diagnosis is easier, and patients with unexplained abdominal mass or ascites as the first symptom, especially those with multiple masses with or without ascites should make full use of routine and imaging examinations. Abdominal water is taken repeatedly for exfoliative cell examination to further confirm the diagnosis. If necessary, laparoscopic examination or early exploratory laparotomy may be performed for early diagnosis and early treatment. For those who have been identified as metastatic tumors of abdominal cavity, they should be searched for as soon as possible according to the pathological characteristics of the tumor. In the primary lesion, in order to take timely and effective treatment, patients with recurrence of abdominal tumor recurrence and implant metastasis, the scope and extent of planting should also be determined to determine the treatment plan.
1. The patient has a history of cancer in the primary intra-abdominal organs or other parts.
2. Clinical symptoms of ascites, anemia and weight decline.
3. Laboratory examinations and imaging studies support the diagnosis of metastatic cancer.
Differential diagnosis
Female peritoneum is more prone to more types of tumor-like lesions or tumors than males. Female peritoneal tumors are divided into three types: mesothelioma, mullerian and metastatic tumors, especially primary peritoneal tumors. More common in women, in recent years, more research on this disease, and collectively referred to as extraovarian peritoneal serous papillary carcinoma (EPSPC), in the previous concept, female pelvic and abdominal peritoneal tumors are mostly metastatic, but in recent years Studies have found that serous tumors, which are thought to be primary tumors of the ovarian epithelium, can also be found in the peritoneum of women. Other tumors with similar structures to ovarian tumors, although rare, can also be used. In the peritoneum of women, it is easier to treat the primary peritoneal borderline serous tumor as peritoneal implantation of ovarian borderline serous tumor, and the primary peritoneal serous adenocarcinoma is diagnosed as ovarian serous adenocarcinoma.
In addition, there is a diffuse peritoneal leiomyomatosis (Leiomyomatosis peritonealis disseminata), a rare disease characterized by a number of subperitoneal smooth muscle nodules scattered in the abdominal or pelvic organs or peritoneum, its pathology The characteristics are: the tumors grow in a nodular shape in the peritoneal cavity and protrude from the peritoneal surface. The tumor is composed of smooth muscle cells which are staggered into bundles under immunoscopic examination. Immunohistochemical staining shows that vimentin, desmin and actin are positive. It indicates that the disease is a benign smooth muscle proliferative lesion occurring in the abdominal cavity of women in the reproductive period, but it must be differentiated from well-differentiated leiomyosarcoma. In imaging examination, the disease is very similar to leiomyosarcoma or ovarian with diffuse cancer. However, some of the reported cases have no ascites, which is clinically important because Leiomyomatosis peritonealis disseminata is a benign disease with a very good prognosis. If diagnosed correctly, patients can avoid unnecessary extensive surgical resection. .
