Research in stomach cancer

We are always learning more about cancer. Researchers and healthcare professionals use what they learn from research studies to develop better practices that will help prevent, find and treat stomach cancer. They are also looking for ways to improve the quality of life of people with stomach cancer.

The following is a selection of research showing promise for stomach cancer. We’ve included information from PubMed, which is the research database of the National Library of Medicine. Each research article in PubMed has an identity number (called a PMID) that links to a brief overview (called an abstract). We have also included links to abstracts of the research presented at meetings of the American Society of Clinical Oncology (ASCO), which are held throughout the year.

A key area of research looks at better ways to diagnose and stage stomach cancer. Researchers are also trying to find ways to help doctors predict a prognosis (the probability that the cancer can be successfully treated or that it will come back after treatment). The following is noteworthy research into diagnosis and prognosis.

Biomarkers are substances, such as proteins, genes or pieces of genetic material like DNA and RNA, that are found naturally in the body. They can be measured in body fluids like blood and urine or tissue that has been removed from the body. A gene mutation or a change in the normal amount of a biomarker can mean that a person has a certain type of cancer. Biomarker tests can help doctors predict the prognosis or response to treatment in people with stomach cancer. Researchers are looking at the following biomarkers to see if they can help doctors predict a prognosis or find out if a person with a particular biomarker would benefit from certain treatments for stomach cancer:

• human epidermal growth factor receptor (EGFR) (Oncotarget, PMID 28199988)
• proliferating cell nuclear antigen (PCNA) (OncoTargets and Therapy, PMID 28138255)
• MGMT promoter methylation (Genetic Testing and Molecular Biomarkers, PMID 28384044)
• PD-L1 (Scientific Reports, PMID 27892511)
• microsatellite instability (ASCO, Abstract 4022)

Looking for cancer cells in washings from the peritoneal cavity may help doctors predict a prognosis for people with stomach cancer. Fluid (washings) is collected after the peritoneal cavity is rinsed with saline solution. A recent meta-analysis of 100 studies found that cancer cells in the washings means there is a greater chance that the cancer has spread to the lymph nodes, a higher risk that the cancer will come back (recur) and a higher chance of dying from stomach cancer (Clinics [Sao Paulo, Brazil], PMID 28076519).

Researchers are looking for new ways to improve treatment for stomach cancer. Advances in cancer treatment and new ways to manage the side effects from treatment have improved the outlook and quality of life for many people with cancer. The following is noteworthy research into treatment for stomach cancer.

Targeted therapy uses drugs to target specific molecules (for example, proteins) inside cancer cells or on their surface. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs may stop the growth and spread of cancer cells while limiting harm to normal cells.

Drugs used to treat other types of cancer may also work for stomach cancer. The following show some promise as future treatments for stomach cancer:

• atezolizumab (Tecentriq) and durvalumab (Targeted Oncology, PMID 26880697)
• avelumab (ASCO, Abstract 167)
• apatinib (Cancer Investigations, PMID 28165839)
• MLN0264 and AZD2171 (World Journal of Gastroenterology, PMID 27570417)
• bevacizumab (Avastin) (Medicine, PMID 28272258)

Immunotherapy uses natural or artificial substances that change the way cells behave. Different types of immunotherapies work in different ways. Some types kill cancer cells or control or change how they behave. Other types strengthen the body’s immune system, control symptoms or lessen side effects of treatment.

Nivolumab (Opdivo) is an immune checkpoint inhibitor that works by blocking the PD-1 checkpoint proteins so immune system cells (called T cells) attack and kill cancer cells. Research has shown that nivolumab was effective when used by itself in people with advanced stomach cancer. A recent clinical trial looked at using nivolumab alone or in combination with ipilimumab (Yervoy) in people who were treated with chemotherapy for stomach cancer that had spread to other parts of the body. Results showed that the nivolumab and ipilimumab improved overall survival slightly and had very few serious side effects (ASCO, Abstract 4014). Researchers are still trying to confirm the role nivolumab may have in treating stomach cancer.

Pembrolizumab (Keytruda) is another immune checkpoint inhibitor drug that blocks PD-1. There are ongoing clinical trials looking at the role of pembrolizumab as a treatment for stomach cancer – either by itself or part of a combination of drugs.

One recent clinical trial looked at using pembrolizumab by itself in people who already had 2 or more different chemotherapy treatments for advanced stomach cancer. The trial was designed to look at how safe and effective pembrolizumab was as a treatment. Results found the strongest response to the drug was in people with PD-1 positive tumours who had 3 previous chemotherapy treatments. There were also responses in people with PD-1 negative tumours and people who had had 4 or more chemotherapy treatments (ASCO, Abstract 4003).

Pembrolizumab with 5-FU and cisplatin was studied as the first treatment for people with advanced or metastatic stomach cancer. Results of this clinical trial showed that this treatment slowed the progression of the cancer, especially in people with PD-1 positive tumours (ASCO, Abstract 4012).

The following is noteworthy research into chemotherapy for stomach cancer.

S-1 is a drug similar to 5-fluorouracil (Adrucil, 5-FU). S-1 contains tegafur, which is a substance that cells in the body change into 5-FU. S-1 is approved for treating stomach cancer in Japan and other Asian countries, as well as in some European countries. More research is needed before it can be approved as a treatment for stomach cancer in North America. This is because more people in North America are likely to have changes in the enzymes that break down 5-FU in their bodies. These changes mean that the drug is not removed from the body very quickly, which can lead to dangerous levels of the drug in the blood that can cause serious side effects. A recent study looked at several studies that compared S-1 by itself to 5-FU or capecitabine (Xeloda) in people with advanced stomach cancer. The results suggest that there were lower numbers of serious side effects in the S-1 group. They also show that more cancers responded to S-1, no matter what geographic area the participant came from (Gastric Cancer, PMID 26754295).

The FLOT4-AIO clinical trial compared 2 chemotherapy drug combinations given before and after surgery for stomach cancer that could be removed with surgery. People were given either docetaxel (Taxotere), oxaliplatin (Eloxatin) and 5-FU with leucovorin (called FLOT) or epirubicin (Pharmorubicin), cisplatin, and capecitabine (Xeloda) or 5-FU (called ECF/ECX). Results of the trials showed that the FLOT chemotherapy showed improvement in both overall survival and progression-free survival, when compared to ECF/ECX (ASCO, Abstract 4004).

Hyperthermic intraperitoneal chemotherapy (or HIPEC) gives heated chemotherapy drugs directly into the peritoneal cavity. Researchers are trying to find out if using HIPEC is an effective way of treating stomach cancer that has spread into the peritoneum after surgery to remove as much of the cancer as possible (International Journal of Hyperthermia, PMID 28124576). A recent review of studies notes that while surgery and HIPEC show promise in treating advanced stomach cancer, more effective drugs or better ways of giving the drugs may improve this treatment (Translational Gastroenterology and Hepatology, PMID 28138643).

The following is noteworthy research into surgery for stomach cancer.

Laparoscopic gastrectomy uses a thin, tube-like instrument called a laparoscope to remove the stomach. The surgeon inserts the laparoscope through small cuts in the abdomen, rather than using a large open incision in the abdomen to remove the stomach. Two recent reviews compared laparoscopic gastrectomy to open gastrectomy as a treatment for stomach cancer that had not spread outside the stomach. Results suggest that there was very little difference between the 2 types of surgery, including between short-term side effects, the need for blood transfusions and long-term survival. More studies are needed to provide better quality evidence that laparoscopic gastrectomy is a safe and effective alternative to open gastrectomy (Cochrane Database of Systematic Reviews, PMID 27030300; Surgical Oncology Clinics of North America, PMID 28279464).

Robotic gastrectomy is a type of laparoscopic surgery where the surgeon sits near the operating table and controls robotic arms to remove the stomach through several small incisions in the abdomen. People who have robotic surgery lose less blood during the operation and have shorter hospital stays compared to those who have open surgery. The specialized instruments make this approach more precise than laparoscopic surgery, but the technology for this surgery is very expensive. Researchers are studying robotic gastrectomy as a way to treat stomach cancer that has not spread outside the stomach (World Journal of Gastrointestinal Endoscopy, PMID 28101302).

More surgery after endoscopic mucosal resection (EMR) may help improve survival. EMR is a very specialized surgery used to treat small (less than 2 cm) early stage stomach cancer that has not spread beyond the inner lining of the stomach (called the mucosa). Sometimes after this type of surgery the pathologist reports that the cancer has spread farther than the mucosa. A recent study compared using more surgery after EMR when the cancer had spread farther to no more surgery. Results show that people who did not have additional surgery after EMR had significantly shorter survival times and the stomach cancer was more likely to come back (ASCO, Abstract 106).

Researchers continue to try to find out more about stomach cancer. Clinical trials are research studies that test new ways to prevent, detect, treat or manage stomach cancer. Clinical trials provide information about the safety and effectiveness of new approaches to see if they should become widely available. Most of the standard treatments for stomach cancer were first shown to be effective through clinical trials.

Find out more about clinical trials.