Urinary N-acetyl-beta-D-glucosaminidase levels in patients with laryngeal squamous cell carcinoma.

Objective: Tumour markers play an important role in the diagnosis of cancer and the early detection of recurrences during follow-up. This study aimed to assess the clinical value of measuring urinary N-acetyl-beta-d-glucosaminidase (U-NAG) levels in patients with laryngeal squamous cell carcinoma.

Design: Prospective, controlled study.

Setting: Tertiary university hospital.

Patients and methods: Our study included 21 patients with primary laryngeal squamous cell carcinoma and 17 cases with recurrent laryngeal squamous cell carcinoma. U-NAG levels of patients with tumours at different stages were compared with a control group of 19 healthy individuals with no known cancer.

Main outcome measures: Patients' age, TNM stage, blood urea, glucose, alanine aminotransferase (ALT), and U-NAG.

Results: A statistically significant difference was found between U-NAG levels of patients with a primary tumour (preoperative period) and the control group (one-way analysis of variance, p = .00; Dunnett's t-test, p = .00). In the postoperative period, the observed trend was that of a significant decrease among primary cases (paired t-test, p = .00). U-NAG levels of patients with a recurrent tumour and patients with a primary tumour (preoperative period) were not significantly different (Tukey honest significant difference test, p = .841). There was no statistically significant difference for blood urea (t = -1.95, p = .064), glucose (t = -1.84, p = .074), or ALT (t = -1.79, p = .080). No significant relationship was found between the TNM stage and preoperative U-NAG levels (p > .05).

Conclusions: These results suggest that U-NAG might be used in the diagnosis of laryngeal carcinoma and the early detection of recurrences during follow-up. Further investigations are warranted to clarify the prognostic significance of U-NAG levels.