Br. J. Surg. 1992, Vol. 79, March, 245-247

Y. Maehara, H. Orita, T. Okuyama, S. Moriguchi, S. Tsujitani, D. Korenaga and K. Sugimachi Department of Surgery I!, Faculty of Medicine, Kyushu University, Fukuoka 812, Japan Correspondence to: Dr Y. Maehara

Predictors of lymph node metastasis in early gastric cancer Data were analysed on 396 patients with early gastric cancer who underwent resection in this department; special reference was made to lymph node metastasis. Metastases were present in the dissected lymph nodes of 47patients (11.9 per cent). The survival rate f o r patients with metastusis to lymph nodes w~aslower than f o r those without such metastasis ( P < 0.05). Lymph node metastasis was associated with larger tumour, a higher incidence of submucosal invasion, a higher rate of lymphatic vessel involvement, an advanced stage of disease and a non-curative resection rate of 6.4 per cent. Multivariate analysis sh0wc.d that the independent risk factors f o r lymph node metastasis in patients with early gastric cancer were large tumour size, lymphatic vessel involvement and invasion into the submucosal layer. In patients with these risk factors, lymph node dissection and postoperative adjuvant therapy should be performed in an attempt to prevent recurrence in the .form of lymph node metastasis.

Early gastric cancer is defined as a lesion in which the depth of invasion is limited to the mucosa or mucosa and submucosa, regardless of whether or not regional lymph node metastasis is evident on histological examination'. With emphasis on early diagnosis, detection of an early gastric cancer and consequent longer survival are now common2. The lymphatic system has an important role in the spread of gastric ~ a n c e r j and , ~ the incidence of lymph node metastasis varies from 7 to 18 per cent'.6. The 10-year survival rate of patients with early gastric cancer and no lymph node involvement is 82-97 per cent, but the rate is less favourable (57-87 per cent) when lymph nodes are involved. This study attempted to determine the type of early gastric cancer which tends to metastasize. The influence of independent clinical and pathological variables on metastasis was determined by logistic regression analysis7-'.

Results

Patients and methods

Risk ,fuctors All of the factors listed in Table I were examined by logistic regression analysis. The independent risk factors for lymph node metastasis were found to be larger tumour size, submucosal invasion and lymphatic vessel involvement (Table 2).

Patients From 1965 to 1985, 396 Japanese patients with early gastric cancer and no evidence of any other malignancy underwent curative gastric resection in this department. Of these, 349 (88.1 per cent) did not have lymph node metastasis. Early gastric cancer occurred in patients with a mean(s.d.) age of 57.7( 12.3) years for those without lymph node metastasis, and 58.3( 11.6) years for those with lymph node metastasis. The ma1e:female ratio was 2: 1 . Pathological diagnosis and classification of resected gastric cancer tissue were carried out according to the general rules for the gastric cancer study in surgery and pathology in Japan'. Stu t ist icul unulysis The BMDP statistical package program (BMDP Statistical Software, Los Angeles, California, USA) for the IBM 4381 mainframe computer (Armonk, New York, USA) was used for all analyses". The BMDP P4F and P3S programs were used for the xz and Mann-Whitney tests to compare data on patients without lymph node metastasis with those on patients with lymph node metastasis. The BMDP PIL program was used to analyse survival by the Kaplan-Meier method and the generalized Wilcoxon test was used to test for equality of the survival curves. The BMDP PLR program was used for simultaneous multivariate adjustment of each covariate, using a backward stepwise logistic regression In this analysis, age and tumour size were included as continuous variables. The accepted level of significance was P < 0.05.

ooO7-1323/92/030245-03

C 1992 Butterworth-Heinernann Ltd

Clinicoputholoyicul factors Table 1 shows clinicopathological data on the 349 patients without and the 47 with lymph node metastasis who underwent gastric resection. These groups differed significantly with respect to tumour size, depth of invasion, lymphatic involvement by the primary tumour and operative curability. In gastric cancer with lymph node metastasis, the primary tumour tended to be larger and the incidence of submucosal invasion and lymphatic involvement was higher. Lymph node metastasis was present in one patient with a tumour

Predictors of lymph node metastasis in early gastric cancer.

Data were analysed on 396 patients with early gastric cancer who underwent resection in this department; special reference was made to lymph node meta...
295KB Sizes 0 Downloads 0 Views