DIFFICULT TO REACH A CONSENSUS FOR GASTRIC CANCER TREATMENT

NEW YORK (Reuters Health) Nov 19 - There was little agreement when an international panel tried to decide recently which multidisciplinary treatments for gastric cancer were appropriate.

The RAND/UCLA Expert Panel, led by Dr. Natalie G. Coburn from Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada, noted in its report, published online November 13th in JAMA Surgery, that surgery, chemotherapy, and chemoradiotherapy have been shown to improve survival in patients with gastric cancer, but up to 43% of patients eligible for multimodality treatment undergo surgery alone.

But there were surprisingly few areas where the panel agreed that treatments were appropriate based on the available research. Surgical resection without preoperative therapy was deemed appropriate for all M0 gastric cancers in proximal and distal tumors, except for patients with T3-4N2-3 gastric cancer and minor symptoms.

For patients with T1-2N2-3 and T3-4N0-3 disease, perioperative chemotherapy is appropriate, but not for patients with T1N0 disease, they said.

Neoadjuvant chemoradiotherapy is appropriate for all T1N0 lesions and for asymptomatic distal T2N0 lesions, but panelists could not agree on other scenarios.

Similarly, the appropriateness of postoperative adjuvant therapy depended on tumor stage.

The panel disagreed over the appropriateness of surveillance imaging following gastrectomy, but they agreed that surveillance endoscopy is appropriate after endoscopic resection.

They also agreed that nonsurgical management of metastatic gastric cancer was appropriate in patients with more than one liver metastasis or more than one site of metastatic disease.

In addition, the panel felt that surgical resection is inappropriate for patients with no major symptoms unless the disease is limited to positive cytology alone, in which case its members disagreed over surgical management.

Intraperitoneal chemotherapy was deemed inappropriate for patients with gastric cancer and peritoneal carcinomatosis, in those with peritoneal disease and ovarian or solid organ metastasis, and in those who have undergone multivisceral resection for T4 gastric cancer without peritoneal disease.

"To our knowledge, these guidelines are the first to be developed for patients with gastric cancer using the RAND/UCLA Appropriateness Method (RAM) process and will aid in multidisciplinary treatment decisions, including patients with metastatic disease," the report concludes. "Furthermore, these processes of care may also be used to identify areas for quality improvement in patients with gastric cancer."

"The present research showed both agreement and disagreement for the treatment strategies in some specific situation of gastric cancer," Dr. Sung Hoon Noh from Yonsei University College of Medicine, Seoul, South Korea, who served on the panel, told Reuters Health. "In keeping with 'personalized medicine,' we have to consider not only the personal gastric cancer status but also the surrounding environment for deciding which treatment is the best for a patient."

"This research showed some agreements but more disagreements," Dr. Noh said. "It is because the biologic characteristics of gastric cancer are heterogeneous, the incidence, location, and stages are different between countries, and the experience of surgeons and oncologists is also different worldwide."

"Chemo-radiation is not popular in Korea and Japan where D2 gastrectomy has long been routine traditionally and practically, because trials failed to show the advantages of radiation therapy after D2 gastrectomy," Dr. Noh explained. "The endoscopic surveillance is popular in Korea and Japan, on the other hands, because the incidence of early gastric cancer is over half of the gastric cancer, which means that a lot of gastric cancer patients survived after treatments."

"However, even in the same Eastern Asian countries, the situation would be different," Dr. Noh said. "In China, a neighbor country of Korea and Japan, the incidence of advanced gastric cancer is much higher than those of Korea and Japan."

"We need more research which combined the opinions of multinational and multidisciplinary experts like this study for helping determine appropriate care for patients in uncertainty," Dr. Noh said.