Metastatic lymph node distribution and pathology correlations in upper and lower gastric cancer patients: A multicenter retrospective study.

BACKGROUND

Gastric cancer (GC) poses a significant threat to public health. However, the clinicopathological features and tumor biological behaviors vary among the GC patients, leading to individual variations in lymph node metastasis. Consequently, the stratification of lymph node dissection according to the specific type, particularly upper GC, has emerged as a prominent area of research.

AIM: To investigate the distribution of metastatic lymph nodes in patients with upper and lower GC and to analyze the differences in related pathological elements and prognosis.

METHODS

Differential analysis between upper and lower GC patients with various clinicopathological factors was performed using the chi-square test and rank-sum test. Logistic regression models were used to identify risk factors for GC lymph node metastasis, while Cox regression models were used to analyze risk factors affecting patient prognosis. The Kaplan-Meier method was used to construct survival curves associated with prognostic risk factors for GC.

RESULTS

Significant differences were observed between the two GC populations regarding tumor diameter, histological grade, pT stage, pN stage, tumor-node-metastasis (pTNM) stage, vascular invasion, and adjuvant chemotherapy usage (all P < 0.05). Lymph node metastasis rates were highest for Siewert type II patients in groups Nos. 1, 3, 2 and 7; for Siewert type III patients in groups Nos. 3, 1, 2 and 7; and for other/unclassified patients in groups Nos. 1, 3, 7, 2. In the lower GC samples, the sequences were Nos. 3, 6, 7, 4. Pathological type, pT stage, pTNM stage, and positive vascular invasion were independent risk factors for development of lymph node metastasis. Age, pathological type, pT stage, pN stage, pTNM stage, vascular invasion, and absence of adjuvant chemotherapy were identified as independent prognostic factors.

CONCLUSION

Upper GC showed a significantly higher malignancy grade and different lymph node metastasis pattern than lower GC.