Epidemiology
Linked to the alimentary habits (in Japan the frequency is especially high). In Europe, it is more frequent in the northern zones, also relater to the alimentary habits (canning).
This cancer is 2-3 times more frequent in men than in women, and its frequency increases with age (average age at the moment of diagnosis is over 60 years). It rarely appears under 45 years.
Risk factors is gastric cancer
- alimentary habits: the high content in nitrosamine in canned food by salt and smoke, are favoring factors to the gastric neoplasm; by contrary, the alimentation rich in fruit and vegetables containing C and A vitamins, protects the stomach.
- the genetic factor: the existence of a familial predisposition to this type of neoplasia
- the low socio-economic standard - may be a favoring factor, probably because of the alimentation, infection Helicobacter Pylori etc.
- the Helicobacter Pylori infection. Helicobacter Pylori was recently appointed by WHO as a first range carcinogen, thus assessing its involvement in the etiopathogenesis of this neoplasm. The Helicobacter Pylori intervention is realized by induction of atrophic gastritis with intestinal metaplasia, which represents a potential evolution towards dysplasia and neoplasia.
- atrophic chronic gastritis: mostly related to the Helicobacter Pylori infection; on this background dysplasic lesions show quite often, evolving from an easy to severe dysplasia (the latter considered in fact an intra-epithelial cancer).
- gastric adenomatous polyps: represent a premalignant stage, especially those with bigger dimensions (over 1 cm, and those over 2 cm have big chances of malignization). Therefore, endoscopic polypectomia of these polyps is indicated at the very moment of their discovery.
- gastric resection in the antecedents (for ulcer) represent a risk factor, generally over 15 years from resection. Usually, an inflammatory stomitis is noticed, as well as lesions of gastritis in the gastric segment left, which may degenerate to malignancy. Therefore, the necessity of endoscopic following of operated stomach after more than 15 years from resection.
- gastritis with giant folds Menetriere has a risk of approx. 15% of malignant transformation.
- gastric ulcer. It is compulsory to take multiple biopsies from each gastric ulcer at every endoscopy and the gastric ulcer healing must be endoscopically checker (with biopsy from the scar). To be mentioned the possibility of some ulcerated cancers, susceptible of scarring under medical treatment.
It may be heterogeneous, depending on how advanced the cancer is. The most frequent symptoms are epigastralgia, freakish appetite leading to total anorexia (sometimes the complete refusal to eat meat), progressive weight loss, and iron deficiency anemia. The epigastric pain may mimic the ulcer symptoms, appearing after meals, often disappearing with gastric protectives. Weight loss may get in the advanced forms to a neoplasic extreme weakness. More rarely, a digestive hemorrhage may appear, endoscopically confirming the diagnosis of gastric cancer. In the advanced forms there might be an epigastric palpable abdominal mass.
Rarely the gastric neoplasia may be discovered starting with an anemic symptoms. Paraneoplasic syndromes may appear migratory phlebitis, acantosis nigricans etc.
Precocious gastric cancer is usually asymptomatic, or there may appear some discrete dyspeptic symptoms. Therefore, it is most often randomly discovered, by occasion of an endoscopy done for an epigastric symptomatology.
Pathological picture in gastric cancer
Histological, the gastric cancer is an adenocarcinoma, with different degrees of differentiation. The less differentiated, the more aggressive it is. There are some neoplasms with histological aspect of “sealed ring”.
Macroscopically: the neoplasm may be protrusive, ulcerated infiltrative. The protrusive aspect, bleeding, is typical to malignity. The ulcerated has irregular margins, infiltrated, rough and must be differentiated via endoscopy from gastric ulcer (b multiple endoscopic biopsies). The infiltrative type of cancer (linitis plastica) realizes a diffuse, extensive infiltration of gastric wall, conferring rigidity to this one, and it must be differentiated by gastric lymphoma.
The transparietal extension of gastric cancer is usually precocious, invading the neighbor organs. The lymphatic extension is also rapid, with the involvement of territories of gastric lymphatic drain and then to a certain distance. The metastases are more often in the liver and lung. Sometimes a carcinomatous peritonitis may appear.
The TNM stadialization (tumor, ganglionar node, and metastasis) allows the establishment of prognosis and of therapeutic approach:
- tumor
- T1 involves the mucosa and submucosa
- T2 penetrates into the muscularis propria
- T3 involving of serosa
- T4 penetrates into the surrounding organs
- N0 lack of ganglionar invasion
- N1 involvement if nodes in the neighborhood
- N2 involvement of distant lymph nodes
- M0 lack of metastases
- M1 distant metastases
It most often starts with a dyspeptic syndrome, epigastralgia, progressive weight loss or an anemic unexplained syendoscondrome. The familial aggregation, or already known premalignant lesions may turn the attention to the disease.
Clinical examination usually brings poor arguments, but in the advanced stages an epigastric mass or/and some supraclavicular lymph nodes involvement may be present.
Paraclinical findings of gastric cancer
- biologically, an iron – deficiency anemia is the rule or severe). There are still gastric neoplasias that may evolve without anemia (linitis plastica).
- Gastroscopy is the election diagnostic method. It allows the visualization of the lesion, signals its characteristics (friability, bleeding) and prelevation of multiple biopsies for the compulsory histological diagnosis confirmation.
The early gastric cancer (superficial – involving only the mucosa and submucosa) is endoscopically classified.
- Type I – protrusive
- Type II – superficial II a - overplane, II b – plane, III c – depressed
- Type III – excavated
- gastric barium-examination is generally a diagnostic surpassed method,generally addressed to the advanced neoplasms or cases with plastic linita(where the diagnostic-help is useful,often superior to the endoscopy.The X-ray examination cannot diagnose all the early stages of the disease and does not allow biopsy prelevation.Diagnostics endoscopy per primam is preferred to a checking-out of an nuclear radiological examination,due to the risks of radiological diagnosis failure.
- echoendoscopy permits the T and M stadialization
- transabdominal ultrasonography may show hepatic metastases or perigastric adenopaties.Sometimes, a casual abdominal ultrasonography may discover an epigastricmass “in cockade”, which may suggest a gastric neoplasia (the subsequent endoscopic check-out is compulsory).
The gastric cancer prognosis depends on the TNM extensions, histological type (poor oe well-differentiated), and patient’s age.
The survival is very good only in the superficial cancers (95% in 5 years). The radical surgery may be done in only 1/3 of cases, in which the 5 year-survival is approx.25%.
Treatment of gastric cancer
A. Surgical. Surgery is the best and radical therapy in gastric cancer. A gastrectomy with lymphadenectomy is performed.Usualy, a subtotal gastrectomy or total (with esojejunostomy) is done, depending on the location and extension of the tumor.
B. Endoscopic. The surgically over passed cancers may still benefit from an endoscopic haemostatic treatment with argon Beamer.
A mucosectomia may also be done in the early stages of cancer (“in situ”). It consists into serum injection under the neoplasia lesion thus transforming it into a sessile polyp, which will be polypectomised afterwards. The piece obtained will be examine by a pathologist.
C. Chemotherapy. Post surgical chemotherapy is generally indicated, almost in more advanced cases, and it includes more cures of Adriamycine with 5- Fluorouracil.
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