RESUMO
IMPORTANCE: The historically reported rates of subclinical cervical nodal metastases in oropharyngeal squamous cell carcinoma (OPSCC) predate the emergence of human papillomavirus as the predominant causative agent. The rate of occult nodal disease with changing etiology of OPSCC is not known, and it is challenging to anticipate which patients will be upstaged postoperatively and will require adjuvant therapy. OBJECTIVE: To assess the rate of nodal upstaging and occult extranodal extension (ENE) in a multi-institutional population of patients with pathologic (p)T1-2 OPSCC treated by transoral robotic surgery and neck dissection. DESIGN, SETTING AND PARTICIPANTS: This retrospective, multicenter cohort study of 92 participants at 2 US institutions (Albert Einstein College of Medicine, Bronx, New York [n = 38], and Icahn School of Medicine at Mount Sinai, New York, New York [n = 39]) and 1 Canadian institution (Princess Margaret Hospital, Toronto [n = 15]) examined the rate of postoperative pathologic upstaging for 92 patients with pT1-2 OPSCC undergoing transoral robotic surgery with neck dissection from August 2007 to December 2016. A neuroradiologist at each site blinded to final pathologic diagnosis reviewed preoperative imaging; these findings were compared with operative pathology and applied for tumor staging using the eighth edition of the American Joint Committee on Cancer Cancer Staging Manual. The statistical analysis was performed on December 18, 2018. MAIN OUTCOMES AND MEASURES: Occult pathologic nodal disease and change in nodal category postoperatively. RESULTS: Of 92 patients who met the inclusion criteria, 76 (83%) were male, and they had a mean (SD) age at surgery of 59.5 (10.5) years; 70 patients (84%) with available p16 status were positive. Five of 18 patients (28%) who had no evidence of nodal disease on imaging had occult pathologic nodal disease. Seven of 32 patients (22%) presenting with no nodal disease or with a single metastatic node on imaging received pathologic upstaging because of multiple positive nodes, indicating implementation of additional adjuvant treatment not anticipated after a priori imaging. Changes included 12 patients (13%) who had pathologic nodal upstaging and 12 (13%) with pathologic nodal downstaging in the eighth edition of staging. In the cohort, 24 patients (27%) had pathologic ENE, and 5 of 39 patients (13%) had occult ENE in the absence of radiographic evidence. CONCLUSIONS AND RELEVANCE: Predicting pathologic staging preoperatively for patients with OPSCC undergoing transoral robotic surgery and neck dissection remains a challenge. Although nodal size, tumor size, and location do not help predict ENE, the presence of nodes on imaging and nodal category may help predict ENE. Our findings suggest a small proportion of patients might benefit from further adjuvant therapies not predicted by preoperative imaging based on occult nodal upstaging and ENE.
RESUMO
BACKGROUND: Knowledge of the rate of occult contralateral nodal disease for oropharynx cancers (OPSCC) in the era of Human Papillomavirus-dominated disease would inform practitioners as to who may be a candidate for unilateral neck management. The objective of this study was to determine the rate of pathologic contralateral positive nodes in patients in OPSCC patients with pT1 and pT2 disease treated with TORS and bilateral neck dissections (BND). METHODS: Retrospective review of medical records was performed at Princess Margaret Cancer Center, Toronto; Icahn School of Medicine at Mount Sinai, New York City; and Montefiore Medical Center, New York City. Patients with pT1-2 N0-3 (AJCC 8th Edition) OPSCC disease treated with TORS and BND were included. RESULTS: Thirty-two patients met inclusion criteria. Twelve patients (37.5%) had a tonsil primary site, 19 (59.4%) patients had a base of tongue primary site, and 1 (3.1%) patient had a pharyngeal wall primary. Twenty-four (75%) patients were known to be p16+. Twenty-seven patients (84.4%) were radiographically negative in the contralateral neck preoperatively, and two of these patients had pathologic contralateral positive nodes. The occult pathologic contralateral nodal metastasis rate was 7.4% (2/27). The sensitivity, specificity, positive predictive value, and negative predictive value of suspicious contralateral nodes on preoperative imaging for pathologically positive nodes were 33.3%, 86.2%, 20% and 93% respectively. In the p16+ subgroup, the occult nodal positive rate in the contralateral neck was 5%. CONCLUSIONS: pT1-2 OPSCC patients undergoing TORS and elective contralateral neck dissection have a low rate of pathologic contralateral nodal positivity.
