Low ALDH1A1 expression in relation to nodal metastasis and survival in tongue squamous cell carcinoma

Multiple biomarkers have been proposed to identify cancer stem cells in tongue squamous cell carcinoma. This study evaluated ALDH1A1, an ALDH1 subtype implicated in head and neck cancer stem cells, and examined its association with histopathological features (depth of invasion, worst pattern of invasion, perineural invasion, grade, inflammation, TNM stage) and prognostic outcomes in tongue tumors.

This cohort study included 55 confirmed cases of tongue squamous cell carcinoma retrieved from the pathology archives of the Cancer Institute, Imam Khomeini Hospital Complex, Tehran, Iran. Four-μm sections were stained immunohistochemically using a mouse monoclonal ALDH1A1 antibody. Histopathological variables were obtained from pathology reports and/or reassessed on slides. Patient contact information was used to follow up on recurrence and death.

High and low ALDH1A1 expression was observed in 27 (49.1%) and 28 (50.9%) cases, respectively, with follow-up periods ranging from 1 to 62 months. The mean age of patients was 57.24 ± 17.82 years, with a range of 24-101 years. The study included 26 men and 29 women. Low ALDH1A1 expression was linked to regional lymph node metastasis (p = 0.01). Disease-specific survival was independently associated with low ALDH1A1 expression (p = 0.045) and T category (p = 0.01). Overall survival was independently associated with age (p-value = 0.04) and T category (p-value = 0.02).

Low ALDH1A1 expression in tongue squamous cell carcinoma was associated with regional lymph node metastasis and reduced disease-specific survival. Larger studies, including analyses across different oral subsites, are needed to clarify the relationship between ALDH1A1 expression and clinicohistopathological factors in oral squamous cell carcinoma.