Olivia Chin1, Eugene Yu2, Brian O'Sullivan3, Jie Su4, Anais Tellier1, Lillian Siu5, John Waldron3, John Kim6, Aaron Hansen5, Andrew Hope6, John Cho6, Meredith Giuliani6, Jolie Ringash3, Anna Spreafico5, Scott Bratman6, Ali Hosni6, Ezra Hahn6, Li Tong6, Wei Xu4, Shao Hui Huang7. 1. Department of Neuroradiology, University of Toronto, Canada. 2. Department of Neuroradiology, University of Toronto, Canada; Department of Neuroradiology and Head and Neck Imaging, Princess Margaret Cancer Centre, University of Toronto, Canada. 3. Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Canada; Department of Otolaryngology - Head & Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Canada. 4. Department of Biostatistics, Princess Margaret Cancer Centre/University of Toronto, Canada. 5. Division of Medical Oncology, Princess Margaret Cancer Centre/University of Toronto, Canada. 6. Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Canada. 7. Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Canada; Department of Otolaryngology - Head & Neck Surgery, Princess Margaret Cancer Centre, University of Toronto, Canada. Electronic address: shaohui.huang@rmp.uhn.ca.
Abstract
PURPOSE: To confirm the prognostic value of radiologic extranodal extension (rENE) and its role in clinical-N classification in nasopharyngeal carcinoma (NPC) treated in a western institution. METHODS AND MATERIALS: NPC treated between 2010 and 2017 were included. Pre-treatment MRI were reviewed for unequivocal rENE and its grade: grade-1: tumour invading through any nodal capsule but confined to perinodal fat; grade-2: ≥2 adjacent nodes forming a coalescent nodal mass; grade-3: tumour extending beyond perinodal fat to invade/encase adjacent structures. Overall survival (OS) and disease-free survival (DFS) were compared between rENE-positive (rENE+) and rENE-negative (rENE-) patients. Multivariable analysis (MVA) confirmed the prognostic importance of rENE and its grade. Staging schemas including rENE in N-classification were proposed and their performance evaluated. RESULTS: A total of 274 patients were eligible (43 cN0; 231 cN-positive). rENE was identified in 83/231 (36%) cN-positive, including grade 1/2/3 rENE in 14/58/11 cases. Compared to rENE-, rENE+ patients had a lower OS (68% vs 89%, p < 0.001) and DFS (58% vs 80%, p < 0.001). MVA confirmed the prognostic importance of grade-2 [HR: OS: 2.85 (p = 0.005); DFS: 2.89 (p < 0.001)] and grade-3 rENE [HR: OS 5.28 (p = 0.004); DFS 3.86 (p = 0.005)], with a trend for grade-1 vs rENE- [HR: OS 2.63 (p = 0.13); DFS 1.49 (p = 0.520)]. We evaluated classifying any rENE as cN3 (Proposal-I) or any grade-2/grade-3 rENE as cN3 (Proposal-II). The stage schema with Proposal-I cN-classification ranked the highest in the performance evaluation. CONCLUSIONS: rENE is an important prognostic factor in this western NPC cohort. We propose classifying any unequivocal rENE as cN3.
PURPOSE: To confirm the prognostic value of radiologic extranodal extension (rENE) and its role in clinical-N classification in nasopharyngeal carcinoma (NPC) treated in a western institution. METHODS AND MATERIALS: NPC treated between 2010 and 2017 were included. Pre-treatment MRI were reviewed for unequivocal rENE and its grade: grade-1: tumour invading through any nodal capsule but confined to perinodal fat; grade-2: ≥2 adjacent nodes forming a coalescent nodal mass; grade-3: tumour extending beyond perinodal fat to invade/encase adjacent structures. Overall survival (OS) and disease-free survival (DFS) were compared between rENE-positive (rENE+) and rENE-negative (rENE-) patients. Multivariable analysis (MVA) confirmed the prognostic importance of rENE and its grade. Staging schemas including rENE in N-classification were proposed and their performance evaluated. RESULTS: A total of 274 patients were eligible (43 cN0; 231 cN-positive). rENE was identified in 83/231 (36%) cN-positive, including grade 1/2/3 rENE in 14/58/11 cases. Compared to rENE-, rENE+ patients had a lower OS (68% vs 89%, p < 0.001) and DFS (58% vs 80%, p < 0.001). MVA confirmed the prognostic importance of grade-2 [HR: OS: 2.85 (p = 0.005); DFS: 2.89 (p < 0.001)] and grade-3 rENE [HR: OS 5.28 (p = 0.004); DFS 3.86 (p = 0.005)], with a trend for grade-1 vs rENE- [HR: OS 2.63 (p = 0.13); DFS 1.49 (p = 0.520)]. We evaluated classifying any rENE as cN3 (Proposal-I) or any grade-2/grade-3 rENE as cN3 (Proposal-II). The stage schema with Proposal-I cN-classification ranked the highest in the performance evaluation. CONCLUSIONS: rENE is an important prognostic factor in this western NPC cohort. We propose classifying any unequivocal rENE as cN3.