Progressive gastric cancer is defined as cancerous tissue invading the stomach wall deeper to or beyond the intrinsic muscular layer.
Some progressive gastric cancer lesions are so invasive outside the stomach that they may be inseparable from surrounding normal tissue or encapsulate large blood vessels, or regional lymph nodes may be fixed, fused into clusters, or metastasized in areas that are not surgically cleared, in which case radical resection is usually not possible. In addition, patients with contraindications to surgery (e.g., poor general condition, severe hypoproteinemia and anemia, malnutrition, severe underlying disease that cannot tolerate surgery, etc.) are also unable to undergo surgery. What is the treatment process for these patients?
Refinement of the examination
Before starting treatment, patients usually need to undergo endoscopy and imaging for characterization, localization, and staging of gastric cancer, and may also need to undergo diagnostic laparoscopic exploration, evaluation of abdominal lavage fluid, etc.
- Gastroscopy and pathologic biopsy are used to confirm the diagnosis and treatment of gastric cancer.
- Thoracic, abdominal and pelvic CT is the basic tool to determine the staging before treatment.
- Magnetic resonance imaging (MRI), laparoscopic exploration, and positron emission computed tomography (PET-CT) can be used as alternative examinations for suspected liver metastases, peritoneal metastases, and systemic metastases after CT examination.
- Routine tests before treatment are based on testing organ function, including routine blood, urine and stool, other blood tests, nutritional status, tumor markers, ECG and echocardiogram, etc.
Treatment
For locally advanced gastric cancer that is inoperable, physicians usually use a combination of treatments based on chemotherapy, and some patients can also be treated with medications to convert the tumor to resectable, which may lead to a chance of radical resection to cure the tumor or prolong survival. In recent years, targeted therapy has also received more and more attention. After patients pass genetic testing and clear tumor typing, doctors will also consider choosing appropriate targeted drugs. In addition, palliative care and humanistic care are also important elements of comprehensive treatment. This part of patients mainly includes the following categories.
Localized tumor is unresectable, but the patient is in good general condition
- Patients with still-limited local tumors who are evaluated for radiotherapy can usually receive concurrent radiotherapy first. The control of the local tumor by radiotherapy may prolong survival, and in a small proportion of patients sensitive to radiotherapy, the tumor may even regress to the point of obtaining radical resection.
- People with too extensive local tumor or lymph node invasion who are assessed to have a target area too large to tolerate radiotherapy usually receive 2 to 4 cycles of chemotherapy first. At the end of chemotherapy, a small number of patients who are sensitive to chemotherapy may be able to undergo surgical resection. If the tumor remains unresectable, the physician will usually consider sequential radiotherapy or simultaneous radiotherapy, and the possibility of surgery will be evaluated again at the end of radiotherapy.
There are reports in the literature that either radical or palliative resection of locally advanced gastric cancer that can tolerate surgery and is in good general condition can improve patient survival.
Localized tumor is unresectable and the patient is in poor general condition
The main goal of treatment for this group of patients is to relieve symptoms and improve the quality of survival. Chemotherapy may prolong their survival compared with best supportive care, including nutritional support, and symptomatic treatment. Radiotherapy may also improve quality of life by significantly relieving some clinical symptoms, such as reducing bleeding, relieving pain, and reducing dysphagia. Palliative radiotherapy may be considered by physicians in patients with advanced tumor disease, advanced age, poor cardiopulmonary function, or multiple comorbid underlying conditions that do not tolerate surgery.
Combined with more severe symptoms of GI obstruction
Patients with more severe GI obstruction are usually considered first for nutritional improvement, including placement of a gastrointestinal nutrition tube, placement of a stent, and short-circuit surgery to divert food around the obstruction to ensure successful treatment. After the nutritional status is improved, the doctor will proceed with chemotherapy or radiation therapy.
Follow-up visits
The purpose of follow-up visits is to monitor disease progression or treatment-related adverse effects, assess nutritional improvement, and so on. The frequency of follow-up is usually every 3 months for the first 2 years after the end of treatment, every 6 months for 2 to 5 years, and once a year after 5 years.
Follow-up visits include hematology, functional status score (PS), and possibly ultrasound or CT every 6 months and gastroscopy once a year. Patients should be seen promptly if symptoms worsen or if new symptoms develop.
Summary
Progressive gastric cancer that is not amenable to surgical resection still has the potential to be downstaged to surgical resection with a combination of therapeutic interventions. Even if surgical resection is not possible, it is possible to prolong survival and improve quality of life through a combination of palliative surgery, radiotherapy, chemotherapy, etc. Patients can choose the most suitable treatment plan for themselves after full communication with their doctors. (Contributed by Wenbin Hou, Department of Gastrointestinal Oncology, The First Hospital of China Medical University)