The stomach is the muscular organ that lies on the left side of the upper abdomen and responsible for receiving food from the esophagus and breaking it down for digestion. It secretes acid and enzymes, contracts periodically, and churns food to enhance digestion of food. The whole process goes smoothly unless there is a pathology that hinders it. 

Today’s topic is about one of the most critical diseases of the stomach. Today’s video is about stomach cancer. 

What is Stomach Cancer? 

The general concept of cancer is the abnormal growth and the uncontrollable division of cells in a certain organ. 

So is the case with stomach cancer. It is the abnormal growth and division of cells that begins in the stomach. 

Stomach cancer, also known as gastric cancer, can affect any part of the stomach. The human stomach is subdivided into four parts:  

1. The fundus, an expanding area curving above the opening of the esophagus into the stomach called the cardiac opening. 
2. The body or the intermediate region, which is the central and the largest part.
3. The antrum, the lowermost funnel-shaped part of the stomach. 
4. The pylorus, a narrow part where the stomach connects with the small intestine. 

Although stomach cancer can affect any part, in most cases in the world, stomach cancer arises from the main part of the stomach, the stomach body. However, in the United States, stomach cancer highly likely occurs where the esophagus meets the stomach, an area known as the gastroesophageal junction. 

The location of cancer in the stomach is a factor that doctors consider to prepare a treatment plan. 

But before jumping into treatment plans, let’s take a deeper dive into why stomach cancer happens? What causes stomach cancer?

It is not clear exactly how stomach cancer occurs; however, research has identified some risk factors that may predispose to gastric cancer. And it is still a subject of ongoing research. 

Gastric cancer begins when there are changes in gastric cells’ DNA. A cell's DNA tells them what to do when to divide, when to stop dividing, and when to die. 

On exposure to certain environmental or genetic changes, these changes tell the cells to grow quickly and continue living. Over time, the accumulating cells form a tumor which, in turn, can invade and destroy nearby healthy tissue. Also, some of the cancerous cells may break off and spread to other distant body parts through blood or the lymph.

Here are some of the risk factors that increase the possibility of developing gastric cancer:

• Gender, gastric cancer is more common in males.
• Age, gastric cancer risk increases with ageing. 
• Ethnicity: Gastric cancer may be more common among certain ethnic groups such as Asians. 
• Geography: worldwide, stomach cancer is more common in East Asia, Eastern Europe, and South and Central America. And is less common in Africa and North America.
• Obesity. It is linked to an increased risk of cancer of the upper part of the stomach. 
• Smoking. The rate of gastric cancer is about doubled in smokers.
• Some types of stomach polyps. 
• Gastroesophageal reflux. 
• Family history of stomach cancer. 
• Long-term stomach inflammation. 
• A diet high in smoked and salty food. 
• A diet low in fibers as in fruits and vegetables. 
• Infection with Helicobacter pylori. It seems to be a major cause of gastric cancer. Long-term infection with this germ leads to atrophic gastritis and other precancerous changes in the mucosal lining of the stomach. It is also linked to some types of lymphoma of the stomach.
• Alcohol use: gastric cancer is strongest in people who have three or more drinks per day. 
• Pernicious anemia in which the stomach lacks the intrinsic factor needed to absorb vitamin B12 from food. 
• History of stomach surgery: Stomach cancer can occur on sectional slices of partial gastrectomies.
• Menetrier disease. A very rare disease in which there’s an overgrowth of the stomach lining resulting in large folds of the inner lining and low levels of acid secretion. 
• Some professions: Coal, metal, and rubber industries. 
• Type “A” blood group: for unknown reasons, people with type “A” blood are at higher risk of getting gastric cancer. 

Some risk factors can be changed such as smoking, alcohol, and obesity, while some others can’t; such as age and ethnicity. But having one risk factor or many doesn’t mean that one will get gastric cancer.

So, how can you know if you get Gastric cancer? What are the symptoms? 

Signs and symptoms might include:

• Nausea. 
• Stomach pain. 
• Vomiting.
• Unintentional weight loss. 
• Heartburn and acid reflux. 
• Swallowing difficulty. 
• Indigestion.
• Bloating. 
• Feeling full after eating small amounts of food. 
• Feeling a lump at the top of your stomach.
• Pain at the top of your stomach. 
• Feeling tired all the time. 
• Frequent burping. 

These symptoms might be common with other conditions. So, if they are persistent and don’t go away with the usual prescribed treatment, you have to see a doctor. 

If your doctor suspected gastric cancer, some investigations might be needed to confirm this diagnosis. Doctors typically don’t do routine screening for gastric cancer because it is not that common. 

Your doctor will typically listen to your complaint and medical history, ask if you have any risk factors or if you have a family member who has had it before. Your doctor then proceeds to physical examination, then ask for some investigations including: 

• Blood tests. 
• Upper GI endoscopy. 
• Endoscopic ultrasound.
• CT scan. 
• Tissue biopsy. 

Your doctor also may suggest an exploratory surgery to find out if your cancer has spread beyond your stomach or not. 

All these pieces of information are so helpful, but the question that goes on mind now is what about treatment? What are the treatment options for gastric cancer? 

Many treatments can fight gastric cancer but the one adapted to each case depends on many factors, such as the cancer stage, spread level, aggressiveness, and of course overall health. The treatment may be surgical or non-surgical. 

The surgical treatment goal is to remove the tumor along with part of the healthy tissue surrounding it called the safety margin. The type of surgery itself varies from one case to another. Some cases are in a very early stage where the tumor is limited to the lining of the stomach. These types are usually removed by endoscopy, a procedure that cuts the tumor from inside the lining of the stomach and called “Endoscopic mucosal resection”. 

If the tumor is located in the antrum, then this part is removed in a procedure called “Subtotal gastrectomy”. When the tumor is located in the body of the stomach, surgeons remove the whole stomach; a procedure known as ” Total gastrectomy”. There are also other palliative procedures to relieve the pressure symptoms associated with the growing cancer. They are only performed in advanced cases of stomach cancer. 

As for the non-surgical treatment, it involves chemotherapy, radiotherapy, and palliative therapy. 

Chemotherapy is a chemical drug given through an intravenous route, they help to kill cancer cells and to shrink the tumor size. It may be used before surgery to shrink the tumor size so it can be easier to remove. Also it can be administered after surgery to make sure there are no remaining cancer cells. 

Radiotherapy, on the other hand, uses high-powered beams of energy directed at the tumor to kill the cancer cells.  It is done before surgery in very special cases. After surgery, its role is to kill the remaining cancer cells. It can also be combined with chemotherapy.

Palliative therapy or care is an option for advanced cases. They are not going to be cancer-free, but they would be pain-free, have the best possible quality of life, and there will be ongoing physical and psychological support for them. 

The traditional treatment options are, so far, so helpful in the battle against gastric cancer. But searching for a personalized treatment plan for each case is a very tiring and frustrating process. One can visit millions of online websites and do a lot of reading and still have no idea where to start. 

But thanks to our scientists and researchers, every day a new drug or a new technique is discovered and there is ongoing research for the most effective, least expensive options. 

The U.S, for instance, they have immunotherapy and targeted drug therapy. 

Cancer cells hide from the immune system, but immunotherapy drugs stimulate the immune system to fight against these cancer cells. 

Targeted drug therapy, on the other hand, targets cancer cells’ weak points and eventually kills them. 

In South Korea, most surgeons perform the extended lymph node dissection when they are surgically removing the tumor. It gave better results and higher survival rates. 

In India, in addition to their affordable prices, they offer targeted drugs such as trastuzumab and imatinib. They attach specific abnormalities in cancer cells and kill them 

In Israel, the main method of treatment is surgery, but they make sure they have eradicated all the cancerous cells by removing some parts of the esophagus and lymph nodes if necessary. 

Starting a treatment journey is hard, but we are here to help get through. 

Our role today is to answer most of questions regarding Stomach Cancer. Today we have Doctor Lee who is a leading doctor at Hanyang University Hospital. He is going to discuss Stomach Cancer with us from an experienced medical point of view.

Interview

What exactly is gastro colonoscopy and how often should it be done?

We usually do gastroscopy and colonoscopy when we do checkups. A gastroscopy is a test that looks at the esophagus, stomach, and duodenum by inserting the endoscope into the mouth. And it can be done just by fasting for one meal.

Colonoscopy is a test that looks at the entire large intestine by inserting an endoscope through the anus. This test requires taking medicine the day before inducing diarrhea to empty out the intestine. So that's the basic method. It’s usually recommended to do gastroscopy once every two years. And it is said that a colonoscopy usually needs to be done every 4 to 5 years.

How about the early signs of stomach cancer?

Stomach cancer usually has early cancer and advanced cancer. In the early stages of stomach cancer, there are typically no symptoms. So it can be said that early cancer has no symptoms. When the cancer progresses into stage 3 and 4. You could get stomach aches, indigestion, weight loss... These symptoms can occur. The important point is that there are no symptoms in the early stages.

What kind of examinations are needed to detect stomach cancer?

First, the most important test is the endoscopy. It's most important that you do an endoscopy. As I said earlier, there are no symptoms at the beginning, so you can't tell whether you have cancer in your stomach or not through symptom detection. So, the most important test is gastroscopy. Diagnosis should be done at an early stage, as the treatments will work well and will have a good outcome. Getting into a habit of receiving an endoscopy every two years is important.

In Korea, the medical checkup system is well made so they run tests for everyone in the whole country every two years. So, it is said that it's important to have a checkup once every two years like that.

How about in the case of stomach cancer, what kind of surgeries are there?

We can divide stomach cancer into early gastric cancer and advanced gastric cancer. Of course, advanced gastric cancer requires surgery. So, you can open the abdomen to remove the stomach, or in some cases, you can cut a hole in the abdomen and insert a laparoscope to cut the stomach. However, in the case of early gastric cancer, it is in its early stages.

In this case, only endoscopic lesions of gastric cancer can be cut out with an endoscope by inserting an endoscope into the mouth. Because that is possible, depending on the progression of the disease, we usually decide whether to perform surgery or just cut with an endoscope.

How many people get stomach cancer every year? And from these people, how many are 100% cured?

Worldwide, it is said that 200,000 people develop stomach cancer per year. And when you look at Korea alone, there are about 30,000 people per year. So, it's a very common cancer in the world as well as in Korea.

In Korea, the treatment works well, but usually stomach cancer patients have a 5 year survival rate of about 25 %. But if you look at the data in Korea, the 5-year survival rate is up to about 70%. It means that if there are 100 stomach cancer patients, 70 of them will live longer than 5 years. And that is because we give an early diagnosis. So, before there are any symptoms, when examined, it is detected and are usually all in the early stages.

When the examination is done after symptoms occur, most of the time it is already past stage 3. So even if there are no symptoms, it is detected in the early stages through regular examination. And this is why we have a high survival rate of stomach cancer in Korea.

Conclusion:

When we deal with cancer, we can look at them from stages – early stages and advanced stages. During the early stage of stomach cancer, there are no symptoms, mostly. When the cancer develops and enters the third and fourth stages, there is stomach pain, digestion is difficult with weight loss. These symptoms can appear, but the important point is that in the early stage there are no symptoms.

The most important examination is gastroscopy. And, like we said before, since there are no symptoms in the early stage, it is hard to detect the cancer through symptoms. So, the most important tool is to perform gastroscopy. It is easier to treat early since it is more successful. It is important to get a gastroscopy every two years. In Korea, everyone is provided with gastroscopy every two years as our screening system is well set up.

If we look at the entire world, there are about 200,000 cases per year. If we look at Korean alone, it is about 30,000 cases per year. So, it is a common form of cancer in both the world and Korea. The five-year survival rate for Korea is about 70%.this rate is higher, and it is thanks to early detection. So, if we have 100 patients undergoing the surgery, about 70 people live past the five-year mark. 

We treat it before there are any symptoms, as part of the overall exams. In such cases, they are almost all early stages. If we diagnose it after there are symptoms, they are mostly stage three or four. So, Korea’s stomach cancer treatment success is based on early detection.