Size of the largest lymph node visualized on multi-detector-row computed tomography (MDCT) is useful in predicting metastatic lymph node status of gastric cancer.

This study was designed to investigate whether the size of the largest lymph node (long-axis diameter [LAD] and short-axis diameter [SAD]) visualized using multi-detector-row computed tomography (MDCT) was useful for predicting the metastatic lymph node (MLN) status of gastric cancer. A retrospective analysis of 305 gastric cancer patients who underwent pre-operative MDCT was performed, followed by a prospective study in 61 gastric cancer patients to determine the diagnostic effectiveness of LAD and SAD. In the retrospective study, the accuracy of LAD and SAD for predicting the MLN status of gastric cancer was 51.1% and 45.9%, respectively. In the prospective study, the accuracy of LAD and SAD measurement and the traditional MDCT method of counting MLNs was 52.5%, 49.2% and 57.4%, respectively; the differences were not significant. In conclusion, the size of the largest lymph node in terms of LAD and SAD visualized on MDCT was useful for predicting the MLN status of gastric cancer, with accuracy comparable to the traditional MDCT method of counting the total number of MLNs detected.