Surgical Puzzle: Concurrent Comprehensive Neck Dissection Strategies Unravelling the Mystery of Carcinoma Unknown Primary when Performed with TORS Radical Tonsillectomy and Mucosal Tongue Base Wedge Biopsy in Northern Indian Cohort

The study delves into the distribution of cervical nodal metastasis among patients diagnosed with carcinoma of unknown primary who underwent definitive diagnostic surgical management in form of transoral robotic surgery assisted ipsilateral radical tonsillectomy and tongue base mucosal wedge biopsy with concurrent therapeutic open ipsilateral neck dissection. We conducted a prospective study at a tertiary care center over two-years, enrolling patients with unilateral neck swelling histopathologically confirmed as squamous cell carcinoma neck metastasis. For cases where the primary site remained undetected despite evaluation, patients underwent Transoral Robotic Surgery (TORS) assisted ipsilateral radical tonsillectomy and tongue base wedge biopsy, along with concurrent open ipsilateral neck dissection. The study examines the clinicopathological correlation of nodal metastasis in carcinoma of unknown primary and explores the concepts of Lymph node yield (LNY) and Lymph node density (LND). Clinicoradiologically, the majority of patients exhibited N2b disease (n = 10/18, 55.55%). However, histopathological examination of the neck dissection specimen revealed N3b disease in the majority (n = 5/17, 29.4%). Neck dissection was aborted for 1 patient with unresectable N3b nodal metastasis during the procedure. The most commonly affected lymph node level clinicoradiologically was level II (n = 18/18, 100%), which corresponded to level II pathologically in most cases (n = 15/18, 88.2%). Ipsilateral radical neck dissection was required in the majority of cases (n = 10/17, 58.82%). The median Lymph Node Yield (LNY) from ipsilateral neck dissection was 30.78 ± 3.52, with the highest Lymph Node Ratio (LNR) detected from level II (11.1 ± 1.56). In the context of carcinoma of unknown primary with secondary neck metastasis, exploring emerging concepts such as Lymph Node Ratio (LNR) and Lymph Node Density (LND) alongside other clinicopathological parameters is crucial. These concepts provide valuable insights into the metastatic burden and may aid in refining prognostication and treatment strategies for patients with this condition.