What is the peritoneum mesothelioma the cause?

(A) causes of morbidity
The etiology and pathogenesis of asbestos exposure and contacts on its very long intervals often more than 30 years as early as 40 years in the 20th century, foreign scholars have discovered that the occurrence of mesothelioma and asbestos exposure close to the shipyard workers, pipeline workers, construction workers, welders and paint the incidence of 300 times more than the average height of a man close relationship between mesothelioma and asbestos exposure has been more and more confirmed by the fact that at the same time Europe and the United States with recognized scholars found that about 60% of peritoneal mesothelioma patients have occupational asbestos exposure history or lung tissue There are asbestos bodies in the use of asbestos-induced pleural mesothelioma in experimental animals is also a small number of animals, peritoneal mesothelioma, peritoneal mesothelioma, note the occurrence and the relationship between asbestos exposure has some different types of asbestos fibers in turn pathogenic risk as follows: crocidolite "amosite" chrysotile is generally believed that a long diameter of 0.5 ~ 50μm asbestos dust first and then through the diaphragm into the respiratory lymphoid tissue or blood into the abdominal cavity and the net deposition of the formation of asbestos bodies in the peritoneal asbestos bodies sometimes can occur around foreign body giant cell reaction to ingestion of asbestos fibers through the digestive tract can also be reached through the intestinal wall and peritoneal mesothelioma from exposure to asbestos have been detected an average of 35 ~ 40 years of peak incidence 45 years after exposure to asbestos-caused mesothelioma, the exact mechanism is not very clear but about 30% of mesothelioma patients with no history of exposure to asbestos fibers and asbestos quantitative examinations found no contact with a large number of asbestos fibers with the performance reported in the literature related to the occurrence of mesothelioma and other factors are history of exposure to radiation therapy thorium dioxide, (usually related to patients receiving diagnostic history) also occurs in patients with a history of Hodgkin increase the risk of mesothelioma
Infection: simian virus (simian virus 40SV40) It is a DNA tumor virus, according to the United States reported in the literature about 50% of the biopsy specimens of patients with mesothelioma it is present in SV40-induced telomerase activity in primary mesothelioma, but does not affect the fibroblasts 72h after infection of wild-type SV40 can be measured telomerase activity after 1 week shows a clear structure of DNA in the cell tower ladder of telomerase activity and SV40 T antigen is directly proportional to the number of SV40 infected mesothelial cells, the telomere enzyme activity is not easy to increase apoptosis of mesothelial cells allows the formation of mesothelioma, easily understood
Mesothelioma also may be related to the following factors: exposure Fluorspar scars of chronic inflammation of tuberculosis genetic susceptibility and other radioactive substances
(B) the pathogenesis of
According to their biological behavior and tumor invasion and scope can be divided into benign and malignant mesothelioma limitations and diffuse mesothelioma cases in the large coverage of about 57.1% occurred in the pleura 39.5%, occurred in the peritoneum can be 1% occurred in the pericardial involving multiple serosal surface or even in the testis sheath
1. Mesothelioma earlier that the genetic organization of two kinds of cells from the surface of the peritoneal mesothelial cells and connective tissue cells, has recently been confirmed to be from a single cell that the mesothelial cells of mesothelial cells to epithelial cells and fiber cells were two kinds of morphological differentiation Dardick (1984) found in sarcomatoid mesothelioma in the region does not show ultrastructural characteristics of fibroblasts display different stages of differentiation characteristics of epithelial cells using immunohistochemical methods Blobel prove cytokeratin polypeptide ( cytokeratin polypeptide) in the fibrous mesothelioma, and the expression of epithelial mesothelioma are wavy fibrin (fibrin) in the same or the same tumor cells also express the two-way display Expression of mesothelioma
2. Peritoneal mesothelioma can be divided into low-grade malignant cystic well-differentiated papillary mesothelioma, mesothelioma and malignant mesothelioma
(1) low-grade cystic mesothelioma: is common in middle-aged women, often located within the pelvic extraperitoneal tumors can invade and more often ill-defined capsule was not obvious in the structure of the surrounding pelvic adhesions aspect for multi-cystic wall smooth capsule containing clear liquid or thin mucous cyst lining flat to low columnar mesothelial cells can be shaped with mild to moderate papillary hyperplasia and metaplasia cyst showed fibrous stromal hyperplasia in which no significant chronic inflammatory cell infiltration
(2) well-differentiated papillary mesothelioma: surgery is not commonly found even in women of childbearing age occur in the general principles of good prognosis for malignant mesothelioma can develop even visible pelvic peritoneum and omentum showed multiple papillary or nodular off-white solid lesion diameter <2cm tumor may also occur in the peritoneum and mesenteric gastrointestinal endoscopic papillary tumor coating the surface of single-storey flat to cuboidal mesothelial cells, rare mitotic nucleus is no different-type cytoplasm axis of fibrous stromal tumors can be seen from the mesothelial cells formed branching tubule-like cord or a piece of solid block occasionally psammoma body
(3) malignant mesothelioma: The tumor was single or multiple dispersed growth at the same time involving the visceral and parietal peritoneum can be classified according to shape and limitations of diffuse-type localized malignant mesothelioma, a clear boundary or envelope was hard and tough pedicle low level of diffuse malignant mesothelioma, malignant peritoneal involvement showed diffuse thickening of the surface of papillary plaque or nodular in general have seen a high degree of malignant peritoneal surface are widely distributed, ranging from the size of the tumor nodules in isolation like strings of beads or was cluster-like clumps from a few millimeters to a few centimeters in diameter was yellow-white or off-white hard like rubber-like material was significantly thicker than the late peritoneal peritoneal tumor tissue was covered by dense white so that organ into a "frozen" (frozen) state of tumor organizations and the abdominal viscera, especially the digestive tract sticky fused with each other easily separated or in the peritoneal surface of abdominal organ with multiple nodular tumor was found in grape-like or diffuse peritoneal surface of diaphragm abdominal peritoneal surface and omentum after the small intestine and mesenteric colon serosal bladder surface or the liver surface and sometimes multiple nodules fused into lumps
Peritoneal mesothelial cell tumor of the general pathological view of human peritoneal mesothelial cell tumor of the general observation is similar to pleural mesothelioma, there are two kinds of types that diffuse peritoneal mesothelial cell tumor and limitations of peritoneal mesothelial cell tumor of general diffuse mesothelioma 75% of malignant mesothelioma of the limitations of the former are mostly benign tumor tissue showed numerous small nodules or plaques on the lining of the parietal or visceral peritoneal tumor development with massive thickening of the films showed a wide range blanket in the parietal peritoneal, or abdominal organs may be associated with the surface of tumor or nodules of varying sizes Duocheng off-white tumor tissue was hard and tough can also have bleeding and necrosis of jelly tumor tissue fibrosis and even glass-like tumor tissue can be changed invasive liver or intestine but rarely invade deep organs in the greater omentum can be completely replaced by tumor tissue intestinal adhesions can occur within the abdominal cavity exudate and even the limitations of bloody ascites in the peritoneal mesothelial cell tumor or nodular tumor tissue showed plaque is located in visceral peritoneal lining, or off-white material was clearly very few hard limits bleeding and necrosis (Figure 1)



3. Peritoneal mesothelial cell tumor of microscopic observation peritoneal mesothelial cells are generally three kinds of tumor histological type:
(1) fibrous mesothelioma: fibrous mesothelioma tumor cells from the elongated spindle cells, spindle cells accompanied by the number of collagen fibers, ranging from the limitations of this type more common in mesothelioma, fibrous mesothelioma in and fibrous tissue is sometimes difficult to distinguish tumor cells were spindle-shaped cells around the tumor may have or may have weave of collagen-like structure of focal calcification or ossification obvious when interstitial fibrosis or hyalinization, when some people call them Desmoid mesothelioma Recently, there were will come from the subcutaneous connective tissue between the source of fibroid tumors is called peritoneal mesothelial cells from the surface, said fibrous mesothelioma was based solely on morphology, but is sometimes difficult to distinguish between the two years (Figure 2)



(2) epithelioid mesothelioma: epithelioid mesothelioma is cube-shaped or polygonal tumor cells often have veins tubular or papillary structures found in most epithelial mesothelioma, diffuse mesothelioma, in the differentiation of tumor cells was different from the state can form well-differentiated tubular or papillary structures can also be presented on-chip block undifferentiated tumor showed solid tumor cells of different sizes of the connective tissue surrounding the tumor tissue of tubular papillary structure or composition of adenoid cystic tubular lining by cubic or flat epithelial-like cells of the same size vacuole nucleus can be seen 1 to 2 nucleoli outline a clear cytoplasm rich in tumor cells, slit-like or form can also be presented, ranging from the size of cysts lined with flat epithelial cells of these Sometimes fissures can be seen within the papillary adenocarcinoma papillary protrusions similar to some cases of solid tumor cells arranged in cord-like or nested structure without adenoid or papillary tumor tissue but sometimes the material surrounding the formation of mucus may have a similar structure of mucus cell morphology in Lake more consistent when the nuclear large and small cytoplasm vacuolization containing mucopolysaccharide material (Figure 3)



(3) mixed mesothelioma: mesothelioma, also known as bi-directional differentiation of the tumor accompanied by the same two kinds of fibers and epithelial components Zllzllki (1980) reported 210 cases of diffuse malignant mesothelioma, epithelioid in 67% 26% mixed fibers accounted for 7 percent of the latter is most common in the limitations of mesothelioma, mesothelioma tumor tissue within the hybrid cells and by epithelial-like morphology similar to the sarcoma-like ingredients synovial sarcoma spindle cell sarcoma-like component formed by the It is often transitional form with the epithelial component and thus can be displayed mesothelioma is a cell from a single source of asbestos-related mesothelioma, we often see this form of mucin stain in differentiating between adenocarcinoma and mesothelioma help but differentiated adenocarcinoma low mucus staining can also be negative and mesothelioma tumor cells can also show positive staining Alcianblue and such mucus can also be found in the extracellular interstitial reticular fiber staining in the tumor cells can be seen between the rich reticular fiber distinct adenocarcinoma helpful when the tumor was found asbestos bodies (asbestosbody) be helpful when the diagnosis of mesothelioma is pleural mesothelioma, in particular due to asbestos and the occurrence of adenocarcinoma of the lung and therefore also the relationship between asbestos bodies found in only a reference value ( Figure 4)



4. Peritoneal mesothelial cell tumor ultrastructure and electron microscopy, especially transmission electron microscopy in the diagnosis of mesothelial tumors have a high value of their ultrastructure is characterized by: mesothelioma tumor cells have a large number of thin brush kind of Microvilli appear on the surface of tumor cells but it can also appear in the cytoplasm, but in adenocarcinoma of the small number of short rod-like microvilli of mesothelioma cells has a huge nuclei prominent nucleoli moderate amount of mitochondria has been rough endoplasmic Net glycogen granules into the surrounding common beam tonofilaments and intracellular vacuole smooth endoplasmic reticulum is not well developed extracellular substrates but most do not have a complete connection can also be found between cells with ultrastructural features of these major desmosome found in epithelial cells or mixed mesothelioma mesothelioma mesothelioma in the fibrous ultrastructure similar to the fibroblast cells in the spindle tumor cells have abundant rough endoplasmic reticulum occasionally a tiny cavity between cells gap as well as the microvilli (Figure 5)



5. Peritoneal mesothelial cell tumors by immunohistochemistry Immunohistochemical differential diagnosis of mesothelioma and adenocarcinoma of definite help cytokeratin (cytokeratin) showed positive in mesothelioma, but CEA was negative or weakly positive; adenocarcinoma CEA mostly strong positive and keratin (keratin) often as a focal positive or negative, but due to various reasons in the literature for the immunohistochemical staining in differentiating mesothelioma and adenocarcinoma of the reports have different results and so therefore can not simply make a final conclusion must be Integrated other technologies to make an objective diagnosis of certain mesothelioma patients associated with metabolic disorders such as reducing blood sugar disorders such limitations occasionally peritoneal mesothelial cells showed multi-cystic tumor can be lined with simple cuboidal or squamous epithelial capsule containing a transparent liquid
Mesothelioma cells, electron microscopy and enzyme histochemical features: mesothelioma mainly by the epithelial-like cells (epithelioid cellEC) fibroblast-like cells (fibroblast-like cellFLC) intermediate cell (interim cellIC) and primitive mesenchymal cells (primary mesenchymal cellPMC ) EC to four kinds of cells characterized by abundant microvilli on cell surface microvilli on their long slender diameter and width and the ratio reached 10:1 ~ 15:1 This is far greater than the proportion of adenocarcinoma of several other tumor cell showed sinus-like gap around the inside of its slender microvilli, there are many intertwined FLC in the rough endoplasmic reticulum are more EC dehydrogenase and oxidase activity in higher and lower hydrolytic activity of the FLC cell activity and the EC On the contrary it may be related to functional activity of the two types of cells different from the
Mesothelioma immunohistochemical features: Since the original mesenchymal cells directly or through intermediate-type cells to epithelial-like cells can also be directly differentiated into fibrous mesothelioma of the immune cells, thus staining the complex types of mesothelial immunohistochemical features of tumor cells, such as in Table 1



As can be seen from the table a variety of mesothelioma, the expression of immunohistochemical reaction of the variety of situations to express their positive and negative results were not 100%, therefore certain abdominal tumors, especially ovarian serous papillary cystadenocarcinoma and epithelial papillary mesothelioma of the tubular structure is difficult to identify the former on the carcinoembryonic antigen expression of only 2% of the pairs of epithelial membrane antigen and human milk fat globulin expression there is a higher percentage of it immunohistochemical staining using the above it is difficult to two are distinguished from the recent application of Ber-Ep4 antibody able to identify malignant mesothelioma and adenocarcinoma Ber-Ep4 pairs of abdominal and retroperitoneal and peritoneal adenocarcinoma metastatic adenocarcinoma of the positive expression rate of 100% while the 115 cases of mesothelioma expression of only 1 case (accounting for 0.87%), therefore the use of a comprehensive analysis of immunohistochemical staining can make a correct pathological diagnosis of mesothelioma, if the conditions are even more improved electron microscope examination