Extracapsular Extension in Lymph Node Metastasis from HPV‐Associated Squamous Cell Carcinoma of the Oropharynx

Abstract

Objective: Oropharyngeal cancer understanding has been greatly advanced with the discovery of the role of HPV. Nonsurgical approaches that utilize chemotherapy-radiotherapy have become common treatment. However, upfront surgery has recently gained momentum with the introduction of transoral approaches (laser/robotic). These approaches have been applied to all stages with excellent results. Method: Determine the rate of extracapsular extension (ECE) in all patients with HPV+ oropharyngeal cancer (70 patients) treated with a neck dissection at our institution since pathologic HPV testing was first instituted (2006 to present). Results: We looked at clinical features such as: T stage, primary site, clinical N-stage, node count, staging, sex, race, smoking, and features on preoperative imaging (cystic?, matted?, multiple nodes, number of nodes, and laterality). Of note we found a relationship between patients with lymph nodes >4 cm on pretreatment imaging having a statistically significant ( P = .019) higher rate of extracapsular extension 47% (4cm). Clinical nodal stages related to rates of extracapsular extension with N1 (28.5% ECE), N2A (50% ECE), N2B (68.9% ECE), and N2C (75% ECE). We also noted that multiple nodes on final pathology also were associated with ECE. In specimens with one positive node, the incidence of ECE was 40.7% ( P = .007). Conclusion: One question in treating these patients with initial surgical approach is predicting who can avoid the toxic effects of radiation and/or chemotherapy. Chemotherapy is often added to the treatment in patients with positive margins and/or ECE. This information will assist in predicting which patients may benefit from a transoral surgery.

Decision management in transoral robotic surgery: Indications, individual patient selection, and role in the multidisciplinary treatment for head and neck cancer from a European perspective

“…Predicting ECE based on physical examination and imaging is often not straightforward; however, there is an association between increasing nodal involvement and risk of ECE . This is of special significance when considering TORS for HPV‐driven tumors, where a small primary is often accompanied by disproportionally advanced nodal disease, which often demonstrates ECE . Although current treatment protocols do not take HPV into account, it is possible that ongoing deescalation trials may result in reduced adjuvant therapy recommendations for HPV nodal disease with ECE in the future.…”