Factors associated with occult ipsilateral and contralateral nodal metastasis in resectable lateralized laryngeal and hypopharyngeal malignancies.

OBJECTIVE: The incidence of occult lymph node metastasis is high in cT4aN0 laryngeal and lateral hypopharyngeal cancers, and bilateral selective neck dissection (levels II–IV) is routinely performed for oncologic clearance. However, the risk, distribution, and determinants of occult contralateral nodal involvement remain incompletely characterised. This retrospective cohort study evaluates the incidence of occult lymph node metastasis, the nodal stations commonly involved, and clinicopathological factors associated with contralateral occult nodal metastasis in patients with cT4aN0 laryngeal and lateral hypopharyngeal cancers. METHODS: The retrospective chart review spanned from January 2018 to December 2023, encompassing all patients who underwent total laryngectomy.150 patients with clinico-radiologically confirmed T4aN0 status and who underwent bilateral selective neck dissection (level II-IV) were included in analysis. A descriptive pathological study was performed to assess occult nodal distribution in resectable lateralised laryngeal and hypopharyngeal malignancies. RESULTS: The incidence of occult lymph node metastasis was 28% (n = 42/150). The most commonly involved lymph node stations were level II (85.7%; N = 36/42) followed by level III (42.8%; N = 18/42) and level IV (9.5%; N = 4/42). pN1 disease was seen in 64.2% (n = 27/42) and multiple occult nodes (pN2) were seen in 35.8% cases. The incidence of contralateral occult lymph metastasis was found to be 11.9% (n = 5/42). The pyriform sinus (OR = 2.922, p = 0.014) and epiglottis involvement (OR = 3.615, p = 0.006) were significantly associated with higher nodal positivity odds, while subglottic extension showed increased odds without reaching statistical significance (OR = 2.174, p = 0.083). Subglottic extension was exploratively associated with the likelihood of contralateral nodal involvement (p = 0.004). CONCLUSION: The risk of occult lymph metastasis in clinico-radiologically cT4N0 laryngeal and lateralised hypo pharyngeal malignancies is high(28%) and statistically significant association is seen with epiglottic and pyriform sinus involvement. The association of contralateral occult lymph node metastasis with subglottic extension need further validation. LEVEL OF EVIDENCE: Level 4.