Symptoms in early stages of the disease are usually vague and nonspecific. As the disease progresses the clinical picture will reflect this. The most frequent initial features at the time of presentation are weight loss and abdominal pain [5]. Other common symptoms are anorexia, nausea, vomiting, indigestion, heartburn, early satiety, postprandial bloating, vomiting, and dysphagia. Furthermore, the epigastric pain is usually mild in the early stages but severe and persistent in advanced disease. Other late features include obstruction of the gastroesophageal junction, gastric outlet, or small intestine. Also, melena, hematemesis. peritoneal and pleural effusions and jaundice may develop.

Physical exam

The most common finding in advanced cases is palpable abdominal mass [5], which may be accompanied by succussion splash and hepatomegaly. Other possible signs of metastatic disease include left supraclavicular adenopathy (Virchow's node) [20], periumbilical node (Sister Mary Joseph nodule) [21], and an anterior axillary node (Irish node).

In cases with peritoneal involvement, a pelvic and rectal exam may reveal an enlarged ovary (Krukenberg's tumor) [22], or a retroperitoneal lesion known as Blumer's shelf. Also, peritoneal carcinomatosis produces ascites.

Jaundice and pallor may be apparent as well.

Complications

Predictors of poor prognosis include paraneoplastic syndromes as dermatomyositis, acanthosis nigricans, and circinate erythemas.

• Virchow's Node

  Here we report a case of PTTM due to occult gastric cancer with metastasis in the left supraclavicular lymph node, also known as Virchow's node. Enlarged Virchow's node is an important indicator of advanced gastric cancer. [ncbi.nlm.nih.gov]

  Several nodal metastases with eponymous names associated with gastric cancer have been described: sister Mary Joseph’s node Virchow’s node Krukenberg’s node Irish node Adenocarcinoma is by far the most common gastric malignancy, representing over 95% [radiopaedia.org]

  When first diagnosed with gastric cancer, ∼ 70% of patients already show metastatic spread to the lymph nodes! [amboss.com]

  Other possible signs of metastatic disease include left supraclavicular adenopathy (Virchow's node), periumbilical node (Sister Mary Joseph nodule), and an anterior axillary node (Irish node). [symptoma.com]

• Supraclavicular Adenopathy

  Other factors of poor prognosis were: diffuse type, presence of metastasis, supraclavicular adenopathy, a palpable tumor and hepatitis or ascites (Table 4 ). [doi.org]

  Statistically significant independent prognostic factors were: TNM staging, diffuse type, metastasis, supraclavicular adenopathy, palpable tumor, and hepatitis or ascites. Social determinants are the main risk factors for SC, but not for survival. [ncbi.nlm.nih.gov]

  adenopathy, located where the thoracic duct joins the subclavian vein at the venous angle. [amboss.com]

  Other possible signs of metastatic disease include left supraclavicular adenopathy (Virchow's node), periumbilical node (Sister Mary Joseph nodule), and an anterior axillary node (Irish node). [symptoma.com]

• Weight Loss

  Weight loss This is weight loss when you are not trying to lose weight. Rarely, extreme weight loss can be a sign of an advanced cancer. Pain You may have pain in your tummy (upper abdomen) or behind your breastbone (sternum). [cancerresearchuk.org]

  Abstract An 81-year-old man was admitted with upper abdominal pain and weight loss. Esophagogastroduodenoscopy revealed a large tumor located from the gastric angle to the body. [ncbi.nlm.nih.gov]

  In early stages it presents with non-specific and vague symptoms, in advanced stages it may cause nausea and vomiting, dysphagia, loss of appetite, abdominal mass or weight loss. Women have an increased risk of lobular breast cancer as well. [orpha.net]

  "If you're losing weight and not dieting, that's something to pay attention to," she explains. Be aware that the weight loss may be gradual. [prevention.com]

• Anemia

  She was found with severe anemia and thrombocytopenia during the third course of chemotherapy. She was diagnosed with TMA based on thrombocytopenia, schistocytosis, hemolytic anemia and renal dysfunction. [ncbi.nlm.nih.gov]

  This condition is called pernicious anemia. Along with anemia (too few red blood cells), people with this disease have an increased risk of stomach cancer. [cancer.org]

  Tests that can help diagnose gastric cancer include: Complete blood count (CBC) to check for anemia. Esophagogastroduodenoscopy (EGD) with biopsy to examine the stomach tissue. [nlm.nih.gov]

  At later stages the following symptoms may occur: General signs Weight loss Chronic iron deficiency anemia; (paleness, fatigue, headaches) Gastrointestinal signs Abdominal pain Early satiety Nausea or vomiting Dysphagia Acute gastric bleeding (hematemesis [amboss.com]

• Fatigue

  The most common symptoms were, respectively: epigastric pain, vomiting, weigh loss, epigastric fullness and fatigue. [web.archive.org]

  They include: decreased appetite diarrhea fatigue nausea and vomiting red, dry skin at the radiation site It seems that some cases of stomach cancer might be prevented. [medbroadcast.com]

  […] particularly vomiting up solid food shortly after eating Diarrhea or constipation Bloating of the stomach after meals Loss of appetite Sensation of food getting stuck in the throat while eating Symptoms of advanced stomach cancer may include: Weakness and fatigue [cancer.net]

  dyspnea, rash, neutropenia, anemia, and myalgia The most common adverse reactions associated with Herceptin in metastatic gastric cancer were neutropenia, diarrhea, fatigue, anemia, stomatitis, weight loss, upper respiratory tract infections, fever, [herceptin.com]

  […] include any of the following: Abdominal fullness or pain, which may occur after a small meal Dark stools Difficulty swallowing, which becomes worse over time Excessive belching General decline in health Loss of appetite Nausea Vomiting blood Weakness or fatigue [nlm.nih.gov]

• Weakness

  They include: Burning belly pain Fullness after a small meal Later symptoms may include: Weight loss or weakness Anemia (low number of red blood cells) Light-headedness Throwing up blood or passing black tarry stool Spreading cancer may cause symptoms [msdmanuals.com]

  The association between vitamin intake and gastric cancer (GC) has been widely debated due to the relatively weak evidence. [ncbi.nlm.nih.gov]

  […] vomiting, particularly vomiting up solid food shortly after eating Diarrhea or constipation Bloating of the stomach after meals Loss of appetite Sensation of food getting stuck in the throat while eating Symptoms of advanced stomach cancer may include: Weakness [cancer.net]

  […] cancer may include any of the following: Abdominal fullness or pain, which may occur after a small meal Dark stools Difficulty swallowing, which becomes worse over time Excessive belching General decline in health Loss of appetite Nausea Vomiting blood Weakness [nlm.nih.gov]

• Anorexia

  A 49-year-old man presented with 5 months' history of abdominal pain, anorexia, and rapid weight loss. He had undergone Billroth-II subtotal gastrectomy for a bleeding gastric ulcer 30 years ago. [ncbi.nlm.nih.gov]

  Other common symptoms are anorexia, nausea, vomiting, indigestion, heartburn, early satiety, postprandial bloating, vomiting, and dysphagia. [symptoma.com]

  […] article; read more in our article on gastric cancer. epidemiology uncommon before the age of 40 years incidence rises rapidly to the age of 70 years (median age) presentation 50% have no symptoms non-specific symptoms in the early stages, e.g. dyspepsia anorexia [radiopaedia.org]

• Pleural Effusion

  Pericardial fluid, pleural effusions, and thickening of the gallbladder wall improved after 3 months of treatment according to computed tomography. [ncbi.nlm.nih.gov]

  There were 2 treatment-related grade 5 AEs (acute kidney injury and pleural effusion). Pembrolizumab is approved for several indications, including as a treatment for patients with lung cancer, melanoma, Hodgkin lymphoma, and other types of cancer. [onclive.com]

  effusions, noncardiogenic pulmonary edema, pulmonary insufficiency and hypoxia, acute respiratory distress syndrome, and pulmonary fibrosis. [herceptin.com]

  Also, melena, hematemesis. peritoneal and pleural effusions and jaundice may develop. Physical exam The most common finding in advanced cases is palpable abdominal mass, which may be accompanied by succussion splash and hepatomegaly. [symptoma.com]

• Vomiting

  Gastric cancer symptoms can be nausea, vomiting and epigastric discomfort which is similar to early pregnancy symptoms. This leads to a misinterpretation and delay in the diagnosis during pregnancy. [ncbi.nlm.nih.gov]

  Sickness (vomiting) Stomach cancer can cause a small blockage in the stomach. This stops food from passing through your digestive symptom which can make you vomit. Rarely, there is blood in the vomit. [cancerresearchuk.org]

  Indigestion or heartburn Pain or discomfort in the abdomen Nausea and vomiting, particularly vomiting up solid food shortly after eating Diarrhea or constipation Bloating of the stomach after meals Loss of appetite Sensation of food getting stuck in the [cancer.net]

  In early stages it presents with non-specific and vague symptoms, in advanced stages it may cause nausea and vomiting, dysphagia, loss of appetite, abdominal mass or weight loss. Women have an increased risk of lobular breast cancer as well. [orpha.net]

  […] common malignant tumors in China, withrelatively high incident rate and mortality among the population. 95% of the gastric cancer is adenocarcinoma. 70% of the patients at the early stage show no obvious symptom, and only small number of them has nausea, vomiting [centerwatch.com]

• Nausea

  Gastric cancer symptoms can be nausea, vomiting and epigastric discomfort which is similar to early pregnancy symptoms. This leads to a misinterpretation and delay in the diagnosis during pregnancy. [ncbi.nlm.nih.gov]

  In early stages it presents with non-specific and vague symptoms, in advanced stages it may cause nausea and vomiting, dysphagia, loss of appetite, abdominal mass or weight loss. Women have an increased risk of lobular breast cancer as well. [orpha.net]

  […] the common malignant tumors in China, withrelatively high incident rate and mortality among the population. 95% of the gastric cancer is adenocarcinoma. 70% of the patients at the early stage show no obvious symptom, and only small number of them has nausea [centerwatch.com]

  In its early stages, the disease is often asymptomatic or accompanied by nonspecific symptoms (e.g., epigastric discomfort, postprandial fullness, or nausea). [amboss.com]

• Loss of Appetite

  In early stages it presents with non-specific and vague symptoms, in advanced stages it may cause nausea and vomiting, dysphagia, loss of appetite, abdominal mass or weight loss. Women have an increased risk of lobular breast cancer as well. [orpha.net]

  Symptoms of stomach cancer are often vague, such as loss of appetite and weight. Gastric cancer is diagnosed via a biopsy of stomach tissue during an endoscopy. Also called stomach cancer. [medicinenet.com]

  Gastric cancer symptoms may include a loss of appetite, indigestion, nausea, stomach discomfort, heartburn, black stool, vomiting, unintentional weight loss, feeling full earlier than normal, and pain after eating. [columbiasurgery.org]

  Nausea and vomiting Difficulty swallowing Heartburn Loss of appetite Weight loss Feeling tired Bloating Vomiting blood (in advanced stages) Cleveland Clinic News & More Cleveland Clinic News & More [my.clevelandclinic.org]

• Diarrhea

  She experienced severe diarrhea immediately after starting the course of S-1 tablets. [ncbi.nlm.nih.gov]

  Infections Increased cough Headache Feeling tired Shortness of breath Rash Low white and red blood cell counts Muscle pain Some patients receiving HERCEPTIN for metastatic stomach cancer had the following side effects: Low white blood cell counts Diarrhea [herceptin.com]

• Abdominal Pain

  A 56-year-old man with complaint of upper abdominal pain exhibited adenocarcinoma upon histopathologic examination of biopsy specimens. At the end of adjuvant chemotherapy, the patient was affected by hearing loss. [ncbi.nlm.nih.gov]

  As the disease progresses, patients experience emesis, abdominal pain, dysphagia, postprandial fullness, etc. Complications include GI obstruction, jaundice, peritoneal effusions, and other features as well. [symptoma.com]

• Jaundice

  Jaundice and pallor may be apparent as well. Complications Predictors of poor prognosis include paraneoplastic syndromes as dermatomyositis, acanthosis nigricans, and circinate erythemas. [symptoma.com]

  […] include: Burning belly pain Fullness after a small meal Later symptoms may include: Weight loss or weakness Anemia (low number of red blood cells) Light-headedness Throwing up blood or passing black tarry stool Spreading cancer may cause symptoms such as: Jaundice [msdmanuals.com]

  […] might include: Indigestion, heartburn or pain that doesn’t go away Bloating after eating Nausea or vomiting after meals Trouble swallowing Persistent burping (belching) Stomach ulcer that doesn’t go away Fluid buildup (ascites) in the abdomen (belly) Jaundice [uclahealth.org]

• Hepatomegaly

  Late in the course, abnormalities include an epigastric mass; umbilical, left supraclavicular, or left axillary lymph nodes; hepatomegaly; and an ovarian or rectal mass. Pulmonary, CNS, and bone lesions may occur. [msdmanuals.com]

  (paleness, fatigue, headaches) Gastrointestinal signs Abdominal pain Early satiety Nausea or vomiting Dysphagia Acute gastric bleeding (hematemesis or melena) Late stage gastric cancer Palpable tumor in epigastric region Gastric outlet obstruction Hepatomegaly [amboss.com]

  Late in the course, abnormalities include an epigastric mass; umbilical, left supraclavicular, or left axillary lymph nodes; hepatomegaly; and an ovarian or rectal mass. Pulmonary, central nervous system, and bone lesions may occur. [merckmanuals.com]

  Physical exam The most common finding in advanced cases is palpable abdominal mass, which may be accompanied by succussion splash and hepatomegaly. [symptoma.com]

• Erythema

  Complications Predictors of poor prognosis include paraneoplastic syndromes as dermatomyositis, acanthosis nigricans, and circinate erythemas. [symptoma.com]

  Paraneoplastic syndromes such as dermatomyositis, acanthosis nigricans, and circinate erythemas are poor prognostic features. Other associated abnormalities include peripheral thrombophlebitis and microangiopathic hemolytic anemia. [emedicine.medscape.com]

  […] occasionally accompanied by nausea and/or vomiting Pain may improve or worsen with eating Gastritis, Atrophic Dehydration (primary cause of morbidity and mortality) Malnutrition (typically a sign of a chronic process) Abdominal pain Borborygmi Perianal erythema [physio-pedia.com]

• Aggressive Behavior

  Abstract Gastric cancer patients with main portal vein tumor thrombus usually have a short survival time, owing to its aggressive behavior. Herein, we report a long-surviving case of gastric cancer with main portal vein tumor thrombus. [ncbi.nlm.nih.gov]

  Alternatively, those with mixed immunophenotype are not infrequently associated with a focus of discohesive neoplastic cells, and are more likely to present an aggressive behavior. References 1 Endoh Y, Tamura G, Motoyama T, et al. [nature.com]

• Peripheral Neuropathy

  Side effects may include: tiredness nausea and vomiting nerve damage (peripheral neuropathy) hair loss diarrhoea anaemia (a lack of red blood cells) weight loss skin changes – such as redness, swelling and a tingling sensation in the palms of the hands [nhsinform.scot]

  Side effects may include: tiredness nausea and vomiting nerve damage ( peripheral neuropathy ) hair loss diarrhoea anaemia (a lack of red blood cells) weight loss skin changes – such as redness, swelling and a tingling sensation in the palms of the hands [nhs.uk]

  Oxaliplatin-based regimens were generally well tolerated, with inferior incidence of severe neutropenia, alopecia, and nephrotoxicity, and higher incidence of severe peripheral neuropathy and diarrhea. [doi.org]

Patients presenting with clinical manifestations that are suggestive of gastric malignancy warrant a thorough assessment that consists of the personal and family history, a physical exam, and comprehensive testing.

Imaging

Upper GI endoscopy is the initial diagnostic tool. Specifically, esophagogastroduodenoscopy (EGD) is very accurate in detecting GC as it provides visualization of the mass. It also allows the operator to obtain a biopsy of the lesion and the surrounding area as well. After establishing the diagnosis, an EUS is utilized to determine the tumor stage and to evaluate the GI tract and adjacent structures. Furthermore, computed tomography (CT) and magnetic resonance imaging (MRI) of the chest, abdomen, and pelvis are obtained to assess for potential metastases to the liver, lymph nodes, etc. A chest radiograph is also important for the same reason. Another modality, the positron emission tomography (PET), may be used to determine the presence of distant disease. Finally, a staging laparoscopy can be considered especially since imaging techniques may not detect small lesions less than 5mm in size.

Laboratory studies

A complete blood cell count (CBC) is important to determine the presence of anemia, which can occur due to GI bleeding, anorexia, or liver impairment. Additionally, electrolyte measurements and liver function tests (LFTs) will clarify the overall clinical picture.

The cancer marker, carcinoembryonic antigen (CEA), is elevated in up to 50% of all cases. Also, cancer antigen (CA) 19-9 is increased in approximately 20% of patients.

Other

Immunohistochemical evaluation for HER2/neu is a crucial component of the workup in patients with metastatic disease [23] since there is a targeted agent for cancers that overexpress this receptor [24].

• Thrombocytosis

  The result showed that patients with thrombocytosis had significant worse overall survival (HR 1.57, 95% CI 1.36-1.81, P CONCLUSION: Pretreatment thrombocytosis is a potential effective predictor of overall survival (OS) for patients with gastric cancer [ncbi.nlm.nih.gov]

• Gastric Lesion

  Upper gastrointestinal endoscopy showed a type-2 gastric lesion (45 mm × 40 mm) in the gastric antrum. The PVTT originated from the main gastric tumor and continued to the superior mesenteric vein. [ncbi.nlm.nih.gov]

  Detection of precancerous gastric lesions and gastric cancer through exhaled breath Haitham Amal 1, Marcis Leja 2, 3, 4, Konrads Funka 2, 3, 4, Roberts Skapars 2, 3, Armands Sivins 2, 3, Guntis Ancans 2, 3, Inta Liepniece-Karele 2, 3, 5, Ilze Kikuste [doi.org]

  What is already known on this topic Gastric cancer is preceded by a series of precancerous lesions, but the risk of gastric cancer in patients with such lesions is not well quantified Only one study provided follow-up data from a nationwide biopsy cohort [bmj.com]

• Pleural Effusion

  Pericardial fluid, pleural effusions, and thickening of the gallbladder wall improved after 3 months of treatment according to computed tomography. [ncbi.nlm.nih.gov]

  There were 2 treatment-related grade 5 AEs (acute kidney injury and pleural effusion). Pembrolizumab is approved for several indications, including as a treatment for patients with lung cancer, melanoma, Hodgkin lymphoma, and other types of cancer. [onclive.com]

  effusions, noncardiogenic pulmonary edema, pulmonary insufficiency and hypoxia, acute respiratory distress syndrome, and pulmonary fibrosis. [herceptin.com]

  Also, melena, hematemesis. peritoneal and pleural effusions and jaundice may develop. Physical exam The most common finding in advanced cases is palpable abdominal mass, which may be accompanied by succussion splash and hepatomegaly. [symptoma.com]

Patients with GC are managed by a team of specialists including gastroenterologists, surgical oncologists, medical oncologists, and radiation oncologists. They will conduct the preoperative assessment and collectively determine the best plan of care in conjunction with the patient's wishes.

Surgery

According to the National Comprehensive Cancer Network (NCCN), the early stages of GC are treated with total or subtotal gastrectomy [25]. Additionally, resection of D2 lymph nodes is also recommended. These include nodes of the following arteries: hepatic, left gastric, celiac, and splenic [25].

Standard treatment

Various agents have been assessed in the neoadjuvant, adjuvant, and metastatic settings. Preoperative drugs may be used to debulk the tumor, which will render it easier for resection. This form of treatment can help evaluate the effect of chemotherapy, reduce relapse, and increase survival rates. One trial reported that perioperative treatment (before and after surgery) with the combination of epirubicin, cisplatin, and fluorouracil showed improvement in survival and shrinkage of tumor size versus the group who was treated with surgery alone [26]. Furthermore, postoperative chemoradiotherapy was shown to prolong disease-free survival and increase overall survival in contrast to patients treated with only surgery [27]. Other studies are comparing patients receiving preoperative and postoperative chemotherapy versus those who are managed with postoperative chemotherapy and radiation.

Targeted agents

For advanced unresectable disease, standard chemotherapy regimens can be given. Additionally, there are alternative treatments that are directed at specific characteristics of the tumor. In the U.S., two drugs have been approved as targeted therapies. Trastuzumab is a monoclonal antibody that inhibits HER2 [28]. Studies have demonstrated that overall survival was improved in patients receiving trastuzumab with standard chemotherapeutic agents versus those who received the latter only [24]. Hence, the HER2 positive disease can be treated with trastuzumab in conjunction with cisplatin and either 5-fluorouracil or capecitabine for individuals who have not received prior therapy for metastatic disease.

Another targeted treatment, ramucirumab, is a monoclonal antibody directed at vascular endothelial growth factor receptors 2 (VEGFR2). This is the first biologic agent that exhibited survival in patients with advanced stages of GC when administered alone [29]. It can be used in advanced cancer following standard chemotherapy.

The prognostic factors for GC are lymph node involvement and depth of the tumor [19]. With regards to patient outcome, localized distal disease represents the best prognosis as more than half of these cases can be cured with surgical resection. In contrast, localized proximal cancer has a 5-year survival rate of 10% to 15%. Furthermore, the disseminated disease has a 5-year survival rate of zero. Unfortunately, the majority of patients are diagnosed with advanced cancer. Note that this cancer exhibits a high rate of recurrence.

The cause of GC is mostly multifactorial in origin as it is composed of genetic and environmental interplay [2]. For example, a diet rich in pickled foods, salty fish, smoked meat [2], red meat, and fat [3] is associated with this cancer. Also, smoking was found to increase the risk of GC by 1.5 to 1.6 times [4]. Very importantly, H. pylori are the primary carcinogen for GC and hence the strongest risk factor [3].

Other risk factors include a history of previous gastric surgery, adenomatous polyps, pernicious anemia, gastric ulcers [5], chronic atrophic gastritis, obesity, radiation exposure, and possibly Epstein-Barr virus (EBV). In contrast, fruit, vegetables, and vitamin C are considered protective factors [3].

GC is the fourth most common cancer worldwide and the third deadliest cancer in men and fifth in women [1]. There are approximately 990,000 new diagnoses annually across the globe [6]. According to the World Health Organization (WHO), GC was responsible for 723,000 worldwide deaths in 2012 [7]. Hence, this cancer represents one of the highest cancer burdens [8].

This type of cancer is most prevalent in regions such as East Asia, Eastern Europe, and South America [9]. For example, its incidence in Korea is 65.9 in 100,000 [10]. In contrast, GC occurs the least in North America and Africa [9]. Specifically, the incidence of GC in the U.S. is 7.8 per population of 100,000 in white non-Hispanic males and 3.5 per 100,000 in white non-Hispanic females [11]. Furthermore, it is the 15th most prevalent cancer in the U.S. [12].

With regards to patient demographics, there is a racial preference. Moreover, GC in U.S. Hispanics is much higher than in white individuals [11]. Additionally, the Maoris in New Zealand as well as the Inuit community exhibit elevated rates [13]. As for gender, males are affected 2 to 3 times as much as females [6].

Tumors can arise in various parts of the stomach, which is divided into the cardia (uppermost portion), fundus (middle), and the pylorus (distal stomach). Most GCs occur in the non-cardia segments. Additionally, 10% will affect more than one portion.

There are two main histological variants of GC, which are diffuse and intestinal [14]. Diffuse cancer is typified by tumor extension and liver metastasis [15]. It usually results from genetic abnormalities [15] such as in hereditary diffuse gastric carcinoma (HDGC). Note that the diffuse type is more common in women and patients below the age of 50 [16].

The intestinal form is characterized by infiltrative growth and dissemination to the peritoneum [14]. Non-cardia intestinal cancer is associated with H. pylori infection. A series of consecutive precancerous lesions known as Correa's cascade describes the malignant process that transforms chronic non-atrophic gastritis to atrophic gastritis, then intestinal metaplasia, and eventually dysplasia. One study demonstrated a correlation between the progression of the cascade and the risk of developing cancer [17]. Note that the intestinal type is more prevalent in elderly males.

Pathogenesis

Oncogenic pathways such as the proliferation/stem cell, Wnt/beta-catenin, and NF-kappaβ have been implicated in more than 70% of GCs. These findings may have an impact on the use of targeted therapies and patient survival [18].

Metastasis

GC can extend to the liver, peritoneum, and distant lymph nodes. Distribution to other sites such as the ovaries, lungs, bone, soft tissue, and the central nervous system is less common. Dissemination occurs through the hematogenous and lymphatic routes. The former method uses the extensive vascular supply of the stomach, which is perfused by the celiac artery, its branches, and sub-branches. The tumor can also spread through the stomach's complex drainage system. Specifically, the celiac lymph nodes represent the primary mode of drainage. Further drainage occurs from other gastrointestinal nodes.

The preventative strategies address the known risk factors. For example, the World Health Assembly recommends dietary modifications such as reducing consumption of salty foods and red meat while increasing the intake of fruits and vegetables. Also, smoking cessation is key since smoking is the greatest avoidable risk for cancer in general. Furthermore, prevention, treatment, and eradication of H. pylori are also important approaches. Finally, countries with high prevalence of GC such as Japan, Korea, Chile, and Venezuela have instituted early mass screening programs for the detection of this cancer.

Gastric cancer (GC) is the fourth most common cancer in the world and is among the most fatal [1]. It results from the combination of genetic predisposition and environmental components. The latter includes Helicobacter pylori infection, salty diets, smoking, and other risk factors. This cancer has a higher occurrence in certain parts of the world such as Eastern Asian countries. Furthermore, the incidence of GC has significantly declined in many developed countries in the past decades. This is likely attributed to an increased consumption of fresh fruits and vegetables and reduced intake of salt. Additionally, infections with H. pylori have decreased due to better hygiene, antibiotic treatment, and screening.

The clinical manifestations of the early disease are usually vague and nonspecific such as weight loss, anorexia, nausea, and indigestion. As the disease progresses, patients experience emesis, abdominal pain, dysphagia, postprandial fullness, etc. Complications include GI obstruction, jaundice, peritoneal effusions, and other features as well.

Patients suspected to have GC should be evaluated thoroughly by a personal and family history, a detailed physical exam, and the appropriate studies. In order to understand the overall clinical picture, it is important to perform a comprehensive preoperative assessment that consists of imaging, pathologic analysis of the biopsy, and blood analysis. Imaging tools include upper gastrointestinal (GI) endoscopy, endoscopic ultrasound (EUS), and other relevant modalities.

The prognosis is better for patients whose cancer is detected early. Hence, aggressive surgery should be performed promptly for resectable tumors. In addition to surgery, there are various treatment regimens that have been studied or are currently being investigated. Management may include a combination of surgery, chemotherapy, radiation, and/or targeted agents.

Preventative strategies have been recommended and implemented worldwide. Lifestyle modifications such as diet adjustment, smoking cessation, and eradication of H. pylori are some of the key approaches.

What is Gastric Cancer?

This also known as stomach cancer, which develops when cancer cells form and grow in the stomach's lining. This cancer is much more common in East Asia, Eastern Europe, and South America than it is in North America. It is also more common in men. It is much less common in the U.S. since people are eating less salty food.

What are the causes?

There are genetic and environmental components that increase the risk of developing gastric cancer. The risk factors include:

• Stomach infection with a bacteria called Helicobacter pylori
• Smoking
• Eating a diet rich in salt, salty fish, and red meat
• History of gastric surgery
• Pernicious anemia
• History of stomach ulcer
• History of inflammation of the stomach
• Stomach polyps

What are the signs and symptoms?

Early symptoms are vague. They include:

• Weight loss
• Loss of appetite
• Nausea
• Indigestion

As the disease progresses and the tumor grows, patients may develop:

• Difficulty swallowing
• Abdominal pain
• Feeling full
• Blood in stool
• Blood in vomit
• Yellow eyes and/or skin
• Constipation
• Diarrhea
• Fatigue

How is it diagnosed?

Patients with a presentation that resembles gastric cancer should be evaluated with a personal and family history, a physical exam, and imaging tests such as:

• Upper GI endoscopy with biopsy: this entails passage of a tube through the mouth, esophagus, and stomach to visualize these structures. A tissue sample can be obtained and sent to the laboratory for testing
• Endoscopic ultrasound
• Computed tomography (CT)
• Chest x-ray
• Positron emission tomography (PET)

How is it treated?

The medical team will decide the best treatment for the patient based on the size of the tumor, the stage of cancer, and the patient's wishes. The following may be options:

• Surgical removal of all or most of the stomach and possibly lymph nodes: this is considered curable
• Chemotherapy
• Radiation
• Chemotherapy and radiation

If the tumor can be resected, a combination of chemotherapy and radiation may be given as a combination after surgery. Also, chemotherapy may be used before surgery.

Can it be prevented?

There are preventative strategies that address the factors that increase the risk of developing this cancer. The following are the key approaches:

• Modify the diet by decreasing salty foods and red meat while increasing fruits and vegetables
• Quit smoking: this is very important to reduce the risk of gastric cancer and other types as well
• Prevent and treat Helicobacter pylori infections
• Countries with high occurrences of gastric cancer have screening programs to detect and catch early cases

What is the prognosis?

If detected in the early stages, gastric cancer can be cured although it may recur. Advanced stages of gastric cancer have a poor prognosis.

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