Preoperative assessment of lymph node metastases in patients w i t h gastric cancer: evaluation of the Maruyama computer program
The probability of survival of patients with gastric cancer depends upon depth of wall penetration by the primary tumour and metastatic lymph node burden. Radical lymphadenectomy may lead to prolonged survival but with increased morbidity. A computer program from Maruyama, National Cancer Centre, Tokyo enables evaluation of individual survival time and inJiltration of lymph nodes, This analysis was applied to a German population. Computer-aided predictions were determined retrospectively using the prognostic factors of sex, age, Borrmann classijication, histology, depth of wall penetration, location and diameter of the tumour. Data were collected from 222 patients at the Technical University of Munich (median age 66 years, sex ratio ( M : F ) 2 : l ) , who had been operated on ( 7 2 per cent total gastrectomy, 28 per cent subtotal gastrectomy) f o r gastric cancer. The predicted results were compared with the postoperative pathological Jindings. The prediction of node metastases was highly accurate (lymph nodes 13-16, 96 per cent; 7-12, 89 per cent; 1-6, 82 per cent). These computer predictions may provide perioperative information of therapeutic value.
The role of lymphadenectomy in surgery for gastric cancer is contr~versial'-~. It may be of value in patients who have only a few lymph node (LN) m e t a s t a s e ~~. ~, but this group of patients is difficult to identify before operation. Maruyama et al. analysed data from 3040 patients operated on for gastric cancer in the National Cancer Centre of Tokyo (NCC Tokyo), and from this analysis a computer program was developed for the evaluation of the survival time and the infiltration of lymph nodes in the individual case6.
This paper evaluates the computer program in a cohort of German patients with gastric cancer to examine the validity of its predictions in this population.