BACKGROUND Glottic cancer, the most prevalent laryngeal cancer site, is a tumor emerging from the vocal cords, with laryngeal squamous cell carcinoma (LSCC) being the most prevalent histological type. Glottic LSCC tends to be diagnosed at an early stage due to early symptoms, allowing curative treatment and a good prognosis. The glottic site has fewer sparse lymph node chains than other laryngeal or head-and-neck sites, which is associated with a low frequency of cervical metastasis. Nevertheless, occult cervical metastasis, a clinically negative (cN0) and pathologically positive (pN+) lymph node, is an important prognostic factor for LSCC, and its frequency in glottic LSCC patients ranges from 0% to 25.2%. Consequently, there is a need to improve the identification of glottic LSCC with occult cervical metastasis, aiming to increase treatment efficacy and the survival rates, mainly in patients with T2 and T3 tumors, in which cervical resection must be elective. We have shown that a high expression of the Activated Leukocyte Cell Adhesion Molecule (ALCAM) protein was associated with cervical metastasis, and worse survival rates. This transmembrane glycoprotein is associated with cell–cell adhesion, epithelial and endothelial interactions, and immune response regulation. OBJECTIVES This study aimed to evaluate the ALCAM levels as a biomarker of occult cervical metastasis. METHODS For this purpose we evaluated ALCAM levels by immunohistochemistry in 111 cN0, cT2/T3 (40.54% cT2 and 59.46% cT3) glottic LSCC patients who underwent surgery with curative intent with bilateral neck dissection at the Head and Neck Surgery Division of the Instituto Nacional de Câncer (Brazil). RESULTS At diagnosis, 82% of patients showed impaired vocal cords. Surgery achieved negative margins in 83.78% of cases. Postoperative findings classified tumors as pT1 (7.21%), pT2 (23.42%), pT3 (52.25%), and pT4 (17.12%); 68.47% were pTNM stage III or IV, and 85.59% were moderately differentiated. Tumor relapse occurred in 13 patients (11.71%), including seven local, three regional, and three distant relapses. The median overall survival was 74.4 months. Occult cervical metastases were observed in 18.92% of patients, and 36% of tumors showed high ALCAM expression. Occult cervical metastasis was associated with high ALCAM expression (p=0.00063), and subglottic involvement (p=0.015). Overall survival analyses showed that high ALCAM expression (p=0.023), occult cervical metastasis (p<0.001), age ≥61 years (p=0.007), impaired vocal cords (p=0.003), pT3/4 classification (p=0.04), tumor stage III/IV (p=0.04), supraglottic (p=0.034) and subglottic involvement (p=0.021), and transglottic tumor presence (p=0.009) were associated with worse prognosis. CONCLUSION High ALCAM expression is a biomarker of occult cervical metastasis in glottic LSCC and affects patients' prognosis.