Compared with assessment via endoscopic examination, assessment through the examination of resected regional lymph nodes can significantly reduce the mortality rate of lung cancer patients: a retrospective study of 222,563 participants from the SEER database

Abstract

Background: Lymph node assessment is essential for determining treatment and evaluating the surgical scope in patients with lung cancer, thus significantly impacting survival prognosis. Surgical resection and endoscopic biopsy are the primary methods for obtaining lymph node samples, yet it remains controversial to determine which approach can provide greater benefit. This study aims to analyze the prognosis and survival outcomes of lung cancer patients who undergo assessment through the examination of resected regional lymph nodes, assessment via endoscopic examination, or assessment based on imaging modalities.

Methods: Data from the Surveillance, Epidemiology, and End Results (SEER) database, comprising 222,563 participants, were analyzed. The outcome variables were overall survival (OS) and lung cancer-specific mortality, while the primary variable was the method of lymph node assessment. Life table, Kaplan-Meier survival, and Cox proportional hazards analyses were conducted, with log-rank Mantel-Cox, Breslow generalized Wilcoxon, and Tarone-Ware tests being applied for intergroup comparisons.

Results: Compared to endoscopic biopsy, lymph node resection examination reduced the risk of death by 15.7% (P<0.001) and the lung cancer-specific mortality rate by 15.5% (P<0.001). Lung cancer patients who underwent regional lymph node resection examination had higher OS rates at 1, 2, 3, 5, 10, and 15 years by 44%, 49%, 47%, 42%, 28%, and 20%, respectively, compared to those who underwent endoscopic biopsy. Additionally, their cancer-specific survival rates were higher at the corresponding time points by 13%, 16%, 17%, 17%, 18%, and 13%, respectively. The mean OS period for patients who underwent endoscopic lymph node biopsy was 25.071 months, whereas for lung cancer patients who underwent regional lymph node resection examination, the average OS was 87.403 months.

Conclusions: In patients with lung cancer, lymph node resection examination significantly reduces mortality and improves survival as compared to endoscopic biopsy.

Keywords: Lung cancer; Surveillance, Epidemiology, and End Results (SEER); lymph node; survival.

Figure 1

Flowchart of participant inclusion. CS, Collaborative Stage; SEER, Surveillance, Epidemiology, and End Results.

Figure 2

Kaplan-Meier survival curves of patient with lung cancer (OS). (A) Overall survival curve. (B) Prognosis of lung cancer patients with different regional lymph node evaluation methods, overall survival rate. (C) Age stratification: overall survival rate. (D) Sex stratification: overall survival rate. (E) Race stratification: overall survival rate. (F) Total number of malignant tumors stratification: overall survival rate. (G) Histology stratification: overall survival rate. (H) Tumor size stratification: overall survival rate. (I) Regional node-positive stratification: overall survival rate. (J) Stage stratification: overall survival rate. (K) Grade stratification: overall survival rate. (L) Primary site stratification: overall survival rate. (M) Laterality stratification: overall survival rate. (N) Median household income stratification: overall survival rate. (O) Surgery stratification: overall survival rate. (P) Radiation stratification: overall survival rate. (Q) Chemotherapy stratification: overall survival rate. OS, overall survival.

Figure 3

Kaplan-Meier survival curves of patient with lung cancer (lung cancer-specific mortality). (A) Cancer-specific death curve. (B) Prognosis of lung cancer patients with different regional lymph node evaluation methods, cancer-specific death rate. (C) Age stratification: cancer-specific death rate. (D) Sex stratification: cancer-specific death rate. (E) Race stratification: cancer-specific death rate. (F) Total number of malignant tumors stratification: cancer-specific death rate. (G) Histology stratification: cancer-specific death rate. (H) Tumor size stratification: cancer-specific death rate. (I) Regional node-positive stratification: cancer-specific death rate. (J) Stage stratification: cancer-specific death rate. (K) Grade stratification: cancer-specific death rate. (L) Primary site stratification: cancer-specific death rate. (M) Laterality stratification: cancer-specific death rate. (N) Median household income stratification: cancer-specific death rate. (O) Surgery stratification: cancer-specific death rate. (P) Radiation stratification: cancer-specific death rate. (Q) Chemotherapy stratification: cancer-specific death rate.

Figure 4

The prognosis of lung cancer patients (surgical patients and non-surgical patients) with different stratification variables (stratified by regional nodes evaluation methods, stage, radiotherapy and chemotherapy). (A1-A4) OS of surgical patients. (B1-B4) Lung cancer-specific death rate of surgical patients. (C1-C4) OS of nonsurgical patients. (D1-D4) Lung cancer-specific death rate of nonsurgical patients. Cause-specific mortality: lung cancer-specific mortality. OS, overall survival.