Cell‐free DNA integrity correlates with lymph node metastasis and predicts short‐term postoperative recurrence in patients with proximal gastric carcinoma after curative gastrectomy

The predictive value of cell‐free DNA (cfDNA) integrity for lymph node metastasis and short‐term postoperative recurrence in patients with proximal gastric carcinoma (PGC) after curative gastrectomy remains unclear. From August 2019 to March 2021, the cfDNA integrity was assessed in 107 patients with proximal gastric carcinoma who underwent total gastrectomy (TG). The correlation between cfDNA integrity and lymph node metastasis was inspected, and the optimal cutoff value of cfDNA integrity for lymph node metastasis was determined. Meanwhile, the cfDNA integrity was identically detected in 91 proximal gastric cancer patients receiving proximal gastrectomy (PG), as well as 41 heathy individuals. The diagnostic value of cfDNA integrity for short‐term postoperative recurrence was assessed in both cohorts. The cfDNA integrity in healthy control was significantly higher than that in TG (p < .001) and PG (p = .0003) cohorts, but not statistically different between the latter two (p = .540). In the TG cohort, the cfDNA integrity was closely correlated to lymph node metastasis. Using the cutoff value of 0.873, the patients were stratified into the cfDNA integrity high and low groups; low cfDNA integrity was associated with a shorter disease free survival (DFS) both in the TG (p = .011) and PG (p = .041) cohorts. Moreover, cfDNA integrity was assessed to possess the most predictive value for postoperative recurrence by ROC curves in both cohorts. Therefore, the cfNDA integrity may correlate with lymph node metastasis in patients with PGC, and predict short‐term recurrence after curative gastrectomy.