Summary:
- This paper recaps an important gastric cancer conference from 2015. It contains up-to-date information about gastric cancer in Canada. It mainly talks about diagnosing and treating the disease. The paper is meant to help doctors learn about the best treatments for their patients. A summary of some of the major talking points from this conference are here.
Link:
Where?
- Canada
When?
- Published 2016
Impact Factor (IF):
- 2.048
This paper is not a primary research study. That means the authors did not conduct their own research. It is a summary of the 17th Annual Western Canadian Gastrointestinal Cancer Consensus Conference. This was a conference held in Edmonton in September, 2015. The purpose of this event was for expert cancer doctors and researchers to discuss new therapies and the best way to help gastric cancer patients in Canada.
This information is important because it describes the treatment options available to gastric cancer patients in Canada. Doctors might use a resource like this to learn more about their patient’s disease. Also, this information can help set clinical practice guidelines. The paper is written mostly to inform doctors about the most up-to-date knowledge regarding gastric cancer treatment. This way, they can choose the best option to help their patients. Some of the highlights from the topics they discussed are here.
- Screening:
- Not everyone in the Canadian general population needs to be screened
- Patients at high-risk for the disease can be screened. But the best screening method is not yet known.
- Higher-risk patients with the CDH1 mutation are recommended to have a prophylactic gastrectomy. This means having surgery to remove the stomach before it develops cancer. This might be helpful because people with this type of gastric cancer often have an aggressive form of the disease. After it is diagnosed, the cancer makes the patient very sick, very quickly. Proactively removing the stomach can get rid of the disease before it becomes severe enough to show symptoms. Or, in the case that the patient does not actually have gastric cancer yet, a gastrectomy can prevent it from developing at all!
- Surveillance:
- It can be hard to track the health of patients after gastric cancer surgery. It is important that patients learn about their disease. This way, they know when to see a doctor if they notice anything wrong.
- Regular follow-up with your doctor is important to make sure patients are staying healthy physically and mentally. This may involve treating any complications from surgery.
- Nutrition: it is extremely common for gastrectomy patients to suffer from iron-deficiency or Vitamin B12 deficiency. So, a patient’s overall health and nutrition should be checked carefully during follow-up.
- Regular blood work and imaging checkups (e.g.: CT, MRI, ultrasound, etc.) are not very helpful for patients who don’t show symptoms.
- Overall, not a lot of research has been done to find out the best way to monitor patient health over longer periods of time.
- Research needs to be done to look at patient Quality-of-Life (QOL) after treatment. Also, to figure out how QOL would change with patients having more/fewer follow-up tests.
- Best surgery:
- The type of surgery used depends completely on the location and type of tumor.
- Generally, surgeons should map out the borderlines of the disease while they are operating. This paper recommends using intraoperative frozen section (IFS) to do this. IFS means that small sections of the cut-out tissue are frozen and examined during surgery. The tissue is examined for signs of cancer cells. This technique can let the surgeon keep track of where they have cut the cancer out from.
- At least 15 lymph nodes should be cut out during surgery for examination.
- In East Asia where gastric cancer surgery is more common, the standard of care involves removing many more lymph nodes than is often done in North America. Research is showing that this is helpful for patient overall survival.
- Where to have surgery done?
- Gastrectomy surgery should be done only at specialized hospitals or treatment centres. Also, the surgeon should be very experienced. This is because the surgery is quite rare in Canada.
- Hospitals and treatment centres where gastrectomy surgeries are performed should work with their provincial government to monitor treatment quality. This means the
government and hospitals work together to create regulations for gastric cancer treatment. Then, they have methods in place to make sure these rules are being
followed. - There is no standard definition for a “high-volume centre”. The “volume” of a centre
describes the number of patients who are treated there each year. Sometimes, a research paper will specify a requirement of one of their study sites to be a minimum patient volume. This is because treating more patients per year gives the surgeon more practice and allows them to improve their techniques.
- Adjuvant or Neo-adjuvant therapy:
- It can be hard to know if a patient should receive therapy (chemotherapy or radiation) before or after their surgery. This depends on the features of the patient, their cancer, and the surgery used.
- Some patients may have contraindications to radiation therapy. This means that for some reason, they are not able to have radiation after surgery. One example of a contraindication could be an autoimmune disease. These patients should at least have chemotherapy after surgery. This chemotherapy could be a fluoropyrimidine-based routine.
- A lot of research has shown that having treatment after surgery is very helpful to increase overall survival. Therapy after surgery can also help to keep the cancer from coming back.
- We do not yet know what the “best” therapy option for each patient is. Thankfully, research is still going on to figure this out.
- Anti-Vascular Endothelial Growth Factor (VEGF) and Immune Therapy in Metastatic GC:
- For a tumor to move (metastasize) from its original (primary) site to a secondary site, it needs a blood supply to deliver nutrients and keep the cancer cells alive.
- Angiogenesis occurs when new blood vessels sprout from existing ones. This way cancer cells can move to different parts of the body with the blood supply.
- Angiogenesis is partly controlled by a group of signalling molecules called vascular endothelial growth factors. When active, these cause blood vessels to grow more. This makes tumor metastasis is more likely.
- Some cancer treatments stop these molecules from working. Examples of these drugs
include Bevacizumab and Ramucirumab. New research is constantly giving us more information about these medications and when they are useful. - Bevacizumab: this drug may not be very helpful in increasing overall survival. It is not prescribed very commonly in advanced gastric cancer.
- Ramucirumab: this drug can somewhat increase overall survival when given with other
chemotherapy drugs. Although, there are some side effects such as high blood pressure. - Immunotherapy: part of the immune system’s job in the body is to regulate growth. It
does this by keeping a system of checks and balances. In this way, it works almost like a government by making sure that one group does not get too much power. It does this by interfering at key checkpoints and communicating between cells. - In cancer, too much cell growth can occur partly because the cancer cells to avoid these checkpoints by “deactivating” them. The immune system either does not realize that the tumor is growing too large, or it cannot do anything to stop the cancer cells.
- Immunotherapy tries to help the immune system recognize cancer cells and stop them from stop them from growing unregulated in this manner. It is a new field of research.
- The results of early studies in immunotherapy are exciting. But, a lot of research is still needed before it can be considered a regular treatment for gastric cancer patients.
- Best chemotherapy:
- There is no standard chemotherapy treatment for gastric cancer. The combination and routine of medicines depends on each patient and their disease.
- If possible, patients should enrol in clinical studies. This way, they can help researchers learn more about gastric cancer. Also, there is a chance that they could receive a helpful new treatment.
- Patients with “HER-2 overexpressed Gastric Cancer”: a combination of fluoropyrimidine, cisplatin and trazustamab is recommended as a first-line therapy
- Patients without HER-2 overexpression: a combination of fluoropyrimidine-platinum or fluoropyrimidine-irinotecan is recommended as a first line therapy
- Second-line therapies include: fluoropyrimidine-platinum, uoropyrimidine-irinotecan, irinotecan, docataxel, paclitaxel, ramucirumab-paclitaxel, and ramucirumab
- A lot of research has been done around the world with different chemotherapy
routines. None of them have been established as being the “best”.
Citation:
- Mulder, K. E., et al. “Report from the 17th Annual Western Canadian Gastrointestinal Cancer Consensus Conference; Edmonton, Alberta; 11–12 September 2015.” Current Oncology 23.6 (2016): 425. Available from: doi: 10.3747/co.23.3384