Role of Imaging and Histopathology for Predicting Neck Node Involvement in Recurrent/Second Primary Squamous Cell Carcinoma (pN-ROC Study)

After improvement in the treatment of oral cancers over the years we now see more patients with recurrent oral squamous cell carcinoma (OSCC) and second primary. Recommendations for addressing the neck (ipsilateral and/or contralateral) in these patients are still unclear and debatable. In this retrospective study we included patients with recurrent and second primary OSCC who underwent surgery between January 2016 and December 2021. We analysed to identify factors and better imaging modality that help predict a pathologically N + neck in these patients. In our cohort of 219 patients treated for recurrent/second primary OSCC, 131 patients underwent a neck dissection along with surgery for primary, out of which 59 patients had pN + neck. Factors that predicted ipsilateral pN + status were the clinical stage (advanced) p = 0.009, 2.724(1.291–5.750), subsite (Tongue + floor of mouth) p = 0.01, 3.105(1.305–7.386), previous treatment received (surgery alone) p = 0.0472.148(1.011–4.562) and histopathology [poorly differentiated squamous cell carcinoma (PDSCC)] p = 0.014, 3.070(1.253–7.519). PET-CECT had the best agreement (p < 0.001, kappa = 0.742) to predict nodal metastasis. There were no factors that could predict contralateral nodal metastasis. Patients with advanced clinical stage, Tongue + floor of mouth subsite, only surgery done previously, and histopathology (PDSCC) had a higher incidence of ipsilateral nodal metastasis in our cohort.