# Is lymph node metastasis an advanced event of gastrointestinal stromal tumor?

## TL;DR

This study shows that lymph node metastasis in gastrointestinal stromal tumors (GISTs) is an advanced stage, with worse survival outcomes compared to non-metastatic GISTs.

## Contribution

The study clarifies the clinical significance of lymph node metastasis in GISTs by comparing survival outcomes across metastatic groups.

## Key findings

- Lymph node metastasis in GISTs is associated with larger tumor size and higher distant metastasis rates.
- Relapse-free survival in lymph node metastasis is worse than no metastasis but comparable to distant metastasis.
- Tumor location, size, and distant metastasis are independent risk factors for lymph node metastasis in GISTs.

## Abstract

The clinicopathological features and outcome of gastrointestinal stromal tumors (GISTs) with lymph node metastasis remain controversial owing to their low incidence. A multicenter retrospective cohort study was conducted to compare the clinicopathological features and oncologic outcomes of GIST without metastasis, with lymph node metastasis, and with distant metastasis.

The medical records of patients with GISTs in 16 large medical centers in China from January 2014 to December 2022 were reviewed. Patients were divided into four groups: no metastasis (988 cases, 89.1%), lymph node metastasis without distant metastasis (75 cases, 6.8%), distant metastasis without lymph node metastasis (36 cases, 3.2%), and distant metastasis with lymph node metastasis group (10 cases, 0.9%). Propensity score matching (PSM) was performed to reduce confounding factors.

A total of 1109 cases of primary GIST were included in this study, comprising 607 males (54.7%) and 502 females (45.3%), with a mean age of 56.6 ± 11.9 years. Compared to that in GIST without lymph node metastasis, the proportion of nongastric GIST was higher in GIST with lymph node metastasis (52.9% vs 40.7%) with a larger tumor diameter (>10 cm: 36.5% vs 18.1%) and more patients with distant metastasis (11.8% vs 3.5%). Tumor location not in the stomach, the largest tumor diameter, and distant metastasis were independent risk factors for GIST with lymph node metastasis (all P < .05). After PSM, 96, 48, 24 patients comprised no metastasis, lymph node metastasis without distant metastasis, and distant metastasis without lymph node metastasis, respectively. The relapse-free survival (RFS) of the lymph node metastasis group was comparable to that of the distant metastasis group without lymph node metastasis (P = .368) and significantly inferior to that of no metastases (P = .042).

The RFS of patients with GIST with lymph node metastasis was comparable to those with distant metastasis and significantly worse than those without metastasis. Lymph node metastasis is an advanced event in GIST.