Separating lymph node stations by the surgeon from the gastric cancer specimen improves the quality of nodal status evaluation

BACKGROUND: In gastric cancer (GC), the pN-stage is an important prognostic factor influencing treatment. Along with the depth of invasion of the tumor, the presence of nodal metastases is one of the most important prognostic factors guiding treatment strategies in gastric cancer. Examining a small number of lymph nodes may lead to understaging of the disease; hence, it is essential for the nodal status to be precisely assessed. In this study, we explored whether dissecting lymph node stations into separate samples by the surgeon from the gastric cancer surgical specimen affects the quality of nodal status evaluation and patient outcome. METHODS: The clinical data of 130 GC patients treated at the Helsinki University Hospital between 2016 and 2019 was reviewed. The performed operations included 59 total and 71 subtotal gastrectomies. The processing of the surgical specimen before the pathological examination was assessed from the operation records and pathology reports. The association of the number of examined lymph nodes with other variables was assessed, and multivariate survival analysis was performed to explore the independent prognostic factors in disease-specific survival. RESULTS: Dissecting lymph node stations into separate specimens before pathological evaluation yielded a significantly greater number of examined lymph nodes compared with a specimen without intervention (median 34.5 vs 21.0, p < 0.001). The pT-stage, the pN-stage, and the extent of lymphadenectomy were identified as independent prognostic factors, whereas dissecting the specimen’s lymph node stations did not associate with survival. CONCLUSIONS: Dissecting lymph node stations into separate specimens results in a greater number of examined lymph nodes, which has the potential to lead to a more reliable pN-stage assessment.