Clinical characteristics of gastrointestinal stromal tumors with lymph node metastasis: A retrospective single-centre case-controlled study.

Abstract

e23509 Background: Lymph node metastasis of gastrointestinal stromal tumors (GISTs) rarely occurs, and lymphadenectomy is not routinely performed in GIST resection. To date, the relevant characteristics and prognosis of GIST patients with lymph node metastasis are not well known. Methods: From January 2010 to December 2021, GIST patients who underwent lymph node resection were enrolled in this study from a GIST referral centre. All patients were divided into either the LN- group (GISTs without lymph node metastasis) or the LN+ group (GISTs with lymph node metastasis). The clinicopathological features and follow-up data were analysed, and propensity score matching (PSM) was conducted to reduce bias caused by confounders. Results: Out of 1024 surgical patients, 198 patients (age, 52.23±13.54 years; 56.6% males) underwent GIST resection with lymph node dissection for lymphadenopathy, and 17 patients had lymph node metastases (17/1024, 1.66%; 17/198, 8.59%). The LN+ group had a higher mitotic count (P = 0.012) and a higher proportion of distant metastasis (P < 0.001) than the LN- group. After PSM, 28 patients were included (18 in the LN- group and 10 in the LN+ group). The LN- group had both longer postoperative progression-free survival (PFS, not reached vs. 15.0 months, P = 0.002) and overall survival (OS) than the LN+ group, but the difference in OS was not statistically significant (not reached vs. 35.0 months, P = 0.069). Conclusions: The rate of lymph node metastasis in GISTs is low. Lymph node metastasis may be a less common form of distant metastasis. Moreover, GIST with lymph node metastasis has an unfavourable prognosis. Further studies are warranted to identify GISTs with lymph node involvement and the potential involved mechanism. [Table: see text]