- What is Stomach Cancer?
- Types of Stomach Cancer
- Stomach Cancer Symptoms
- Stomach Cancer Diagnosis, Screening and Staging
- Stomach Cancer Prognosis
Stage I Gastric Cancer (Early Stomach Cancer)
Surgical removal (resection) of the tumor is the only chance for a possible cure for stomach cancer. It is the best option in early stage gastric cancer. Traditionally surgery may involve limited resection or gastrectomy. Endoscopic mucosal resection (EMR) is a new procedure that can spare the resection of stomach.
Endoscopic Mucosal Resection (EMR)
Patients with well-differentiated, small superficial lesions with minimal potential for spread can undergo an EMR with complete resection of the tumor without resection of the stomach or lymph nodes. It involves injection of fluid into the submucosa of the stomach to elevate the affected area. A complete mucosal resection of the lesion is then performed endoscopically. EMR is not suitable for a tumor that has invaded the submucosa as there is a high risk of spread to lymph nodes.
Limited Resection of the Stomach
Limited resection of the stomach is an alternative option if EMR is not viable, thereby avoiding gastrectomy. This procedure is considered for small lesions where the full thickness of the stomach wall with along with the complete lesion is removed.
Gastrectomy with lymph node dissection is the main option if limited resection or EMR is not viable. A tumor limited to the lower (pyloric or distal) end of the stomach can be treated with a subtotal gastrectomy and lymph node surgery. Tumors of the proximal end (cardiac end) of the stomach require total gastrectomy with lymph node removal. For some cancers of the gastroesophageal junction, esophagectomy (removal of the esophagus) may also be necessary while some can be managed with removal of the stomach and the abdominal part of esophagus (extended gastrectomy).
Stage II and III Gastric Cancer
Gastrectomy with lymph node removal surgery is the mainstay of treatment in all patients. In addition partial removal of the pancreas or spleen may be required in some patients. Surgical resection alone may not be sufficient for curing the cancer in most patients.
Pre-operative neoadjuvant chemotherapy (administered before surgery) and post-operative adjuvant chemotherapy (administered after surgery) is often employed in addition to surgery to reduce the high risk of recurrence following surgery alone. The chemotherapy agents commonly used for adjuvant or neoadjuvant therapy are various combinations containing agents like :
- mitomycin C
Adjuvant therapy with systemic chemotherapy following surgery has shown some benefit in preventing or delaying recurrence and improves the survival rate. Sometimes the adjuvant chemotherapy may be given intraperitoneally immediately after surgical resection of stomach in patients with high risk of intraperitoneal spread. Recently a combination of chemotherapy (fluorouracil and leucovorin containing regimen) with radiotherapy (chemoradiotherapy) is being used post-operatively with greater success.
Neoadjuvant chemotherapy can be of help in decreasing the stage of the primary cancer and thereby increase the possibility of complete resection of the primary tumor. It also provides an option for early treatment of microscopic metastatic lesions.
Advanced Gastric Cancer
Chemotherapy with best supportive care should be considered for patients with advanced gastric cancer, if they can tolerate it. It offers a better survival advantage than supportive care alone.
Single-drug chemotherapy may be adopted in patients with poor performance status. Drugs known to produce partial response like 5-fluorouracil, mitomycin C, or cisplatin may be used for single-drug therapy. Other possible drugs that may be of use in single-drug therapy includes capecitabine, docetaxel, irinotecan, and epirubicin. The single-drug treatments produce response rates of 10% to 25% however the response is often short-lived.
Combination therapy has been found to have modest improvement in survival, compared to the single-drug therapy and hence combination therapy may be administered in patients who can tolerate it. Commonly employed combination therapy regimens include cisplatin-fluorouracil (CF), epirubicin, cisplatin and flurouracil (ECF) and docetaxel, cisplatin and flurouracil (DCF). Other newer regimens considered for gastric cancer include irinotecan-fluorouracil-leucovorin (FOLFIRI) and fluorouracil-leucovorin-oxaliplatin (FOLFOX).
In a patient with incurable gastric cancer with a poor prognosis, palliative surgeries are done to provide symptomatic relief and improve the quality of life. The frequent symptoms for which patients undergo surgery includes pain, bleeding, gastric or esophageal obstruction and vomiting. The surgeries performed include :
- gastrojejunostomy – connecting the stomach and jejunum to overcome obstruction of stomach
- palliative gastrectomy – removal of the stomach
- gastrostomy – opening of stomach externally to abdominal wall for feeding
Palliative Radiation Therapy
The role of radiotherapy in advanced gastric cancer is limited to palliative radiotherapy. It may be used for easing of symptoms like bleeding, obstruction or pain.