Every cancer patient receives a diagnosis of their disease and then learns about their medical care, and treatment options. Even more, many patients must also prepare themselves for a host of other practical issues and consequences during their treatment for their cancer. Most importantly, though, patients need to have as much clear information as possible about their diagnosis and their treatment options, so that they can be as full of understanding and participation as possible in discussions with their oncologists.
Stomach cancer or gastric cancer is a disease where abnormal cells grow in the stomach lining. The factors that determine the best possible treatment in stomach cancer are the staging of the cancer, the patient’s overall health status, location of the primary tumor and the cancer cells’ specific biological features that could influence to disease’s response to treatment.
Understanding the Role of HER2 in Stomach Cancer
The HER2 protein is found on the surface of most normal cells in the body. It is a growth factor receptor which, when bound by the appropriate ligand, triggers a cascade of signal transduction events which ultimately results in increased cell proliferation. Abnormalities in the HER2 gene, found on chromosome 17, result in stomach cancer cells overexpressing of the HER2 protein. HER2 positive gastric cancers therefore represent a unique group of stomach cancers which can be treated with HER2 targeted therapies.
While some stomach cancers are sensitive to conventional chemotherapy that is designed to kill off rapidly dividing cancer cells, others are not. Instead, targeted therapies may be considered for patients with her2 positive stomach cancer treatment that interfere with the specific way that the cancer cells are growing due to the excessive amount of HER2 protein on their surface.
Not all stomach cancers are HER2 positive. The HER2 status of a tumor needs to be tested and confirmed by a pathologist. The results are then considered by the oncologist together with other factors that determine the appropriate treatment for the individual patient.
How Doctors Diagnose HER2-Positive Gastric Cancer
Depending on the individual case, several investigations may be needed to arrive at a definitive diagnosis and to determine the extent of stomach cancer. An upper gastrointestinal endoscopy allows the stomach and duodenum to be examined and for a biopsy to be taken. A pathologist can then examine the biopsy for cancer cells. If cancer is found, additional tests may be required to determine the degree to which the cancer expresses HER2 protein. Further tests can then be carried out to determine if the HER2 gene has been amplified in the cancer cells.
Additional testing by a pathologist includes confirming that cancer cells are present and determining the tumor’s HER2 status. The amount of HER2 protein in cancer cells can be measured by immunohistochemistry and the HER2 gene amplified in cancer cells by in situ hybridization. Depending on the findings of the imaging studies and in view of the general health of the patient further diagnostic tests may be necessary to assess the extent of the disease.
By understanding the findings from the diagnostics carried out by the doctors and whether any more tests are required, patients and their families will be in a better position to establish the extent of the cancer and how it will be treated.
Exploring HER2 Positive Stomach Cancer Treatment Options
Treatment for her2 positive stomach cancer can be determined by factors like the stage of the cancer, the patient’s general health, past treatment, and the molecular characteristics of the tumor. With all these different factors, there is no one size that fits all treatment for her2 positive stomach cancer. Additional treatments for advanced or metastatic gastric cancer may include targeted therapies against HER2 in combination with chemotherapy. For eligible patients with HER2-positive gastric cancer, treatment options may include HER2-targeted therapies such as tislelizumab.
If cancer can be removed with surgery, then this may be recommended. In some cases, it may be appropriate to have chemotherapy before and/or after the surgery to try to manage the tumor growth. Other treatments, such as radiotherapy, immunotherapy, or other systemic therapies, may be considered depending on the individual case.
It is important to consider the potential benefits and limitations of a treatment as well as its risks. With every treatment, the oncology team has specific goals, such as disease control or, in some cases, treatment with curative intent, the prolongation of the patient’s life or the improvement of the patient’s quality of life. Patients may find it helpful to discuss the following points with their doctor prior to the start of their therapy: the goals of the proposed treatment, its duration, potential side effects and finally the expected treatment outcomes
Patients and families researching her2 positive stomach cancer treatment should also understand how tumor testing, disease stage, and previous therapies influence the treatment plan.
Understanding Biomarker Testing Beyond HER2
As mentioned before, HER2 is not the only biomarker which might influence the treatment decision. Other such as PD-L1 expression or the mismatch repair deficient or microsatellite unstable status of the tumor might be determined as well.
Some other tumor tests can give information about the tumor’s biology. For instance, if cancer is immunotherapy-sensitive then testing for biomarkers such as PD-L1 can provide information that helps guide treatment selection for eligible patients. Each biomarker test is relevant for certain types of tumors at different stages of the disease and in the context of specific treatments according to clinical guidelines. Patients and families can ask their doctors whether all relevant biomarker tests have been performed on the patient’s tumor and if so, which new treatment options have become available based on the results of the biomarker tests.
Preparing for Treatment and Managing Side Effects
Understanding the side effects of a patient’s cancer treatment before it is given is an important aspect of their preparation and looking after their needs during their cancer treatment. Some examples of side effects are fatigue, nausea, loss of appetite, diarrhea and others, each with different severity in individual cases.
It is also important for patients with reduced appetite or weight loss to be well-nourished and keep hydrated. A healthcare professional or an oncology dietitian can provide the necessary information on the best foods for a patient’s specific circumstances.
Help the patient by attending their appointments, keeping a record of their medication, arranging for someone to drive them, and keeping a record of their symptoms between their hospital visits. Report to their doctor if the patient experiences persistent vomiting, becomes dehydrated, has increasing pain or has difficulty eating and drinking. Immediately seek urgent medical care if the patient vomited blood or passes black, tarry stools.
It’s also very important to list all the current medications, the vitamins and supplements and any health problems that the patient may have had in the past. All this information is very important in case there are any drug interactions and for the appropriate monitoring to take place.
Making Informed Decisions with the Oncology Team
While there is much that the patient and family can do before a discussion with the cancer treatment team, it is also important to remember that treatment is often an evolving process. Much can change following a treatment. The oncology team may modify a patient’s treatment in response to new test results, side effects or decline in a patient’s general health.
A more efficient consultation can be created by patients and their families by outlining the questions that need to be answered by the team, bringing all of the medical information up to date and sharing the patients’ priorities with the healthcare team. Understanding unfamiliar terms and asking for further explanation can also help prevent confusion.
There are many unknowns following a stomach cancer diagnosis but with the information available on tumor testing, treatment options and the various forms of support offered to patients and their families, those affected can access appropriate care and make informed decisions about their treatment.
Disclaimer: The information provided in this article is intended for educational purposes only and should not be interpreted as medical advice, a clinical guideline, or a recommendation for any specific treatment.