Prognostic value of serum neutrophil gelatinase-associated lipocalin in metastatic and nonmetastatic colorectal cancer.

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) expression is increased in epithelial cancer patients, but studies showing its relation to prognosis are scarce. We aimed to test the ability of preoperative serum NGAL levels (pNGAL) to predict recurrence in metastatic and nonmetastatic colorectal cancer (CRC) patients.

METHODS: This retrospective study determined pNGAL levels in 60 healthy individuals, 47 patients with nonmetastatic CRC, and 70 patients with metastatic CRC undergoing curative neoplastic resection. Patients were divided into low- and high-pNGAL groups using a median series-based cutoff.

RESULTS: The mean ± SD pNGAL in CRC patients (nonmetastatic and metastatic) was 102.3 ± 66.6 (median 91.4). Nonmetastatic CRC and metastatic CRC patients had higher pNGAL than healthy controls (88 ± 64 and 112 ± 67 vs. 0.6 ± 0.3, respectively, both p < 0.0001). Nonmetastatic CRC patients with deeper tumor invasion and metastatic CRC patients with shorter disease-free interval after CRC resection had higher pNGAL. pNGAL levels correlated with neoplastic tissue volume. CRC patients with recurrence had higher pNGAL than those without recurrence (118 ± 64 vs. 88 ± 66, p = 0.013), and high-pNGAL patients had a higher recurrence rate (59.3 vs. 36.2 %, p = 0.016). Median pNGAL-based risk classification had a sensitivity of 62.5 % for predicting neoplastic progression in CRC patients and 74.3 % for predicting neoplastic progression during the first year after metastatic CRC resection.

CONCLUSIONS: pNGAL is higher in CRC patients than in the healthy population, which indicates a potential screening role. High-pNGAL levels are associated with higher neoplastic tissue volume, characteristics of neoplastic invasion, and recurrence, showing a prognostic utility mainly in metastatic CRC patients.