Stomach cancer, also known as gastric cancer, is a malignant growth that develops in the lining of the stomach. It is a relatively rare but often aggressive form of cancer, with symptoms that can include abdominal pain, unexplained weight loss, indigestion, and nausea. The exact cause of stomach cancer is not always clear, but factors such as chronic infection with the bacterium Helicobacter pylori, a family history of the disease, and certain lifestyle choices like smoking and a diet high in salted and smoked foods can increase the risk. Early detection is crucial for successful treatment, which may involve surgery, chemotherapy, and radiation therapy.
What is Stomach Cancer
Stomach cancer, also known as gastric cancer, is a type of cancer that develops in the cells of the stomach lining. It is a relatively common cancer, but its incidence has been declining in many parts of the world. Stomach cancer often develops slowly over several years, and it may not cause noticeable symptoms in its early stages.
There are several types of stomach cancer, with the most common being adenocarcinoma, which starts in the glandular cells lining the stomach. Other types of stomach cancer, such as lymphoma and gastrointestinal stromal tumors (GISTs), are less common but can also occur in the stomach.
What Causes Stomach Cancer
Stomach cancer, also known as gastric cancer, typically develops over time and is often associated with several risk factors. The exact cause of stomach cancer is not always clear, but several factors may increase the risk of its development:
Helicobacter pylori infection: This bacterium is a major risk factor for stomach cancer. It can lead to chronic inflammation of the stomach lining and increase the likelihood of cancer development.
Dietary factors: A diet high in salty, smoked, or pickled foods, as well as low consumption of fruits and vegetables, may increase the risk of stomach cancer.
Tobacco and alcohol use: Smoking and heavy alcohol consumption have been linked to an increased risk of stomach cancer.
Family history: A family history of stomach cancer may raise an individual’s risk, as there could be a genetic predisposition.
Previous stomach surgery: People who have undergone certain types of stomach surgery, such as a partial gastrectomy, may have an increased risk of stomach cancer.
Chronic gastritis: Long-term inflammation of the stomach lining, often caused by factors like H. pylori infection, can increase the risk.
Pernicious anemia: This condition, where the body cannot absorb vitamin B12 properly, is associated with a higher risk of stomach cancer.
Certain inherited conditions: Some genetic syndromes, like hereditary diffuse gastric cancer (HDGC), can increase the risk.
Aging: The risk of stomach cancer increases with age, with most cases occurring in people over the age of 60.
Gender: Stomach cancer is more common in men than in women.
Symptoms of stomach cancer
Indigestion and heartburn
- Persistent discomfort or burning sensations in the upper abdomen, sometimes worsened after eating.
- Pain or discomfort in the upper abdomen, often described as a vague, gnawing sensation.
Nausea and vomiting
- Frequent or persistent nausea and vomiting, which may contain blood.
Loss of appetite
- A reduced desire to eat and unexplained weight loss.
- Also known as dysphagia, it can occur as a result of a tumor blocking or narrowing the esophagus.
Feeling full after small meals
- Early satiety, where you feel full even after consuming a small amount of food.
- General weakness and tiredness, which can result from anemia (a shortage of red blood cells) caused by stomach bleeding.
Blood in the stool
- Stools may appear dark, black, or tarry due to bleeding in the stomach or upper gastrointestinal tract.
- Hematemesis, the vomiting of blood or coffee-ground-like material.
- Yellowing of the skin and the whites of the eyes, which can occur if the tumor obstructs the bile duct.
Swelling or lumps in the abdomen
- These may be caused by an enlarged stomach, tumors, or enlarged lymph nodes.
How is it diagnosed?
Diagnosing stomach cancer typically involves a combination of medical history, physical examinations, and various diagnostic tests. The specific steps for diagnosis may vary depending on a patient’s symptoms and medical history. Common methods and tests used to diagnose stomach cancer include:
Medical History and Physical Examination
The doctor will start by taking a detailed medical history and conducting a physical examination to evaluate your symptoms and any risk factors for stomach cancer.
Blood tests can be performed to check for signs of anemia, as stomach cancer can lead to internal bleeding and a decrease in red blood cells.
Various imaging techniques can help visualize the stomach and surrounding areas, including:
- Upper Endoscopy (Gastroscopy): This involves inserting a thin, flexible tube with a camera (endoscope) down the throat to directly examine the inside of the stomach. Biopsies can be taken during this procedure for further analysis.
- CT Scan (Computed Tomography): A CT scan can provide detailed cross-sectional images of the abdomen, helping to identify the size and location of the tumor.
- X-ray: Sometimes, a series of X-rays may be taken after you drink a contrast material to help visualize the stomach.
- Barium Swallow: This is a special X-ray where you swallow a contrast material (barium) that coats the esophagus and stomach, making it easier to see abnormalities on X-rays.
The definitive diagnosis of stomach cancer often requires a biopsy, where a small tissue sample is taken from the suspicious area during an endoscopy or surgery. A pathologist then examines the tissue under a microscope to confirm the presence of cancer and determine its type and stage.
Endoscopic Ultrasound (EUS)
EUS combines endoscopy with ultrasound to create detailed images of the stomach wall and surrounding lymph nodes. It helps determine how deeply the cancer has penetrated the stomach wall.
In some cases, a surgeon may perform a laparoscopy, a minimally invasive surgical procedure, to directly inspect the abdomen and assess the extent of the cancer.
Certain molecular tests can be performed on the biopsy sample to identify specific genetic mutations or markers, which may help determine the most appropriate treatment.
Stages of stomach cancer
Stomach cancer, also known as gastric cancer, typically progresses through several stages, which are important for diagnosis, prognosis, and treatment planning. The stages are typically described using the TNM system, which stands for Tumor, Nodes, and Metastasis. This system helps to categorize the extent and severity of the cancer. Additionally, the American Joint Committee on Cancer (AJCC) provides a staging system for stomach cancer. The stages are as follows:
Stage 0 (Tis, N0, M0)
This is the earliest stage of stomach cancer.
Cancer is confined to the innermost layer of the stomach lining (mucosa) and has not spread to lymph nodes or distant sites.
Stage I (T1, N0, M0)
Cancer has invaded the deeper layers of the stomach wall (submucosa or muscularis propria) but has not spread to lymph nodes or distant organs.
Stage IIA (T2, N0, M0)
Cancer has penetrated more deeply into the stomach wall (serosa) but has not spread to lymph nodes or distant sites.
Stage IIB (T3, N0, M0)
Cancer has invaded the serosa and may extend into nearby structures, but it has not reached lymph nodes or distant organs.
Stage IIIA (T1-3, N1, M0 or T4a, N0, M0)
In this stage, cancer may have spread to a small number of nearby lymph nodes but has not reached distant sites.
Stage IIIB (T4b, N0-1, M0 or T1-3, N2, M0)
Cancer may have invaded nearby structures, like the spleen or major blood vessels, or it may have spread to more lymph nodes, but it has not metastasized to distant organs.
Stage IIIC (Tany, N3, M0)
In this stage, cancer may have invaded any depth of the stomach wall and has spread to multiple lymph nodes but has not metastasized to distant sites.
Stage IV (Tany, Nany, M1)
Cancer has metastasized to distant organs or structures, such as the liver, lungs, bones, or distant lymph nodes.
Treatment of Stomach Cancer
The treatment of stomach cancer, also known as gastric cancer, depends on various factors including the stage of the cancer, the patient’s overall health, and the specific characteristics of the tumor. Treatment options for stomach cancer typically include surgery, chemotherapy, radiation therapy, targeted therapy, and immunotherapy. The treatment plan is usually tailored to the individual patient’s needs.
Surgical removal of the tumor and surrounding tissue is the primary treatment for early-stage stomach cancer. Depending on the extent of the disease, the surgeon may perform a partial gastrectomy (removing a portion of the stomach) or a total gastrectomy (removing the entire stomach). Lymph nodes in the area may also be removed.
Chemotherapy involves the use of drugs to kill cancer cells or slow their growth. It can be used before surgery (neoadjuvant chemotherapy) to shrink the tumor, after surgery (adjuvant chemotherapy) to kill any remaining cancer cells, or as the primary treatment for advanced-stage stomach cancer.
Radiation therapy uses high-energy X-rays or other forms of radiation to target and kill cancer cells. It is sometimes used in combination with surgery or chemotherapy, or as a palliative treatment to relieve symptoms in advanced cases.
Targeted therapy drugs are designed to target specific molecules or pathways involved in the growth and spread of cancer. Trastuzumab, for example, targets HER2-positive stomach cancers, and ramucirumab targets blood vessel formation in tumors.
Immunotherapy is a newer approach that stimulates the body’s immune system to fight cancer. Immune checkpoint inhibitors, such as pembrolizumab, may be used in certain cases of advanced stomach cancer, particularly those with microsatellite instability-high (MSI-H) or mismatch repair-deficient (dMMR) tumors.
Patients with advanced stomach cancer may require palliative care to manage symptoms and improve their quality of life. This may include pain management, nutritional support, and emotional support.
Long Term Outlook
The long-term outlook (prognosis) for stomach cancer depends on several factors, including the stage at the time of diagnosis, the extent of the disease, the effectiveness of treatment, the patient’s overall health, and other individual factors. Stomach cancer is often diagnosed at an advanced stage because symptoms may not appear until the cancer has progressed. Here are some general observations about the long-term outlook for stomach cancer:
Early-Stage Stomach Cancer
When stomach cancer is diagnosed at an early stage, before it has spread beyond the stomach, the prognosis is generally more favorable. Surgical removal of the tumor and nearby lymph nodes can be curative in some cases. The five-year survival rate for localized stomach cancer can range from 50% to 90% or higher, depending on various factors.
Advanced Stomach Cancer
Unfortunately, most cases of stomach cancer are diagnosed at an advanced stage. In these cases, the cancer has typically spread to nearby organs or distant sites. The prognosis for advanced-stage stomach cancer is less optimistic. Treatment is aimed at controlling the disease, relieving symptoms, and improving quality of life. The five-year survival rate for advanced stomach cancer is generally lower, often ranging from 5% to 20%.
Response to Treatment
The effectiveness of the treatment plays a significant role in the long-term outlook. Some patients with advanced stomach cancer may respond well to chemotherapy, targeted therapy, or immunotherapy, which can extend survival and improve quality of life. The response to treatment varies among individuals.
Even when stomach cancer is successfully treated, there is a risk of recurrence. Regular follow-up care is essential to monitor for any signs of cancer returning.
The patient’s general health and ability to tolerate treatment also impact the long-term outlook. Patients who are in good health and can withstand aggressive treatments may have a better prognosis.
Palliative care and supportive services can improve the quality of life for patients with advanced stomach cancer, even if the cancer cannot be cured. Managing symptoms, providing nutritional support, and addressing emotional and psychological needs are crucial aspects of long-term care.
The Bottom Line
“Early detection and timely treatment are crucial for improving the bottom line in stomach cancer, offering better chances of survival and quality of life.”