▲ (From the left) Professor Ji Yong Ahn and Professor In-Seob Lee

While early gastric cancer can be treated by a relatively simple endoscopic procedure in some cases, surgical gastrectomy is performed upon the slightest possibility of lymph node metastasis because gastrectomy with lymph node dissection remains the standard treatment. Whether or not lymph node metastasis exists can be judged after surgery. However, findings reported from recent research suggested that the possibility of metastasis can be predicted before surgery.

AMC team of Professor Ji Yong Ahn and Professor Jin Hee Noh of the Division of Gastroenterology and Professor In-Seob Lee of the Division of Stomach Surgery analyzed 1,025 patients who underwent total gastrectomy due to early gastric cancer located in the upper stomach during the period between January 2001 and December 2017. The team developed a matrix for lymph node metastasis prediction depending on tumor size and depth as well as the presence of lymphovascular and neurological invasion. Tumor was categorized into two groups according to size (>=2cm or < 2cm), and the early-stage cancer was divided into 16 cases depending on whether the tumor invaded into mucosa, upper part of submucosa or even deeper.

▲ (left) Professor Ji Yong Ahn performing endoscopic resection on an early gastric cancer patient

▲ (right) Professor In-Seob Lee (second from left) performing partial gastrectomy on an early gastric cancer patient

The predicted possibilities of lymph node metastasis for each number of cases demonstrated statistical difference. For example, the possibility of lymph node metastasis was 1.3% when the tumor size was smaller than 1cm, the tumor invaded into the upper part of submucosa and lymphovascular or neurological invasion was not present. However, the possibility was approximately 75% when the tumor size exceeded 2cm, the tumor invaded into the lower part of submucosa and lymphovascular or neurological invasion was present. In order to test the data, the research team performed a statistical evaluation on the effectiveness of the prediction matrix for lymph node metastasis in early-stage gastric cancer and 83% accuracy was demonstrated as a result.

It is expected that the possibility of cancer metastasis and the quality of life of the patients will be considered together in the treatment of early gastric cancer, leading to more cases of first-attempt endoscopic resection or performing partial gastrectomy where the tumor is located to preserve the stomach.

The research findings were recently published in the Journal of Gastric Cancer (IF=3.72).