Risk and Rate of Occult Contralateral Nodal Disease in Surgically Treated Patients With Human Papillomavirus−Related Squamous Cell Carcinoma of the Base of the Tongue

Abstract

IMPORTANCEThe optimal treatment strategy for patients with human papillomavirus (HPV)−related oropharyngeal squamous cell carcinoma (OPSCC) of the base of the tongue (BOT) has not been sufficiently studied.OBJECTIVE To investigate the rate of and risk factors for occult contralateral nodal disease in patients with HPV-related BOT OPSCC undergoing transoral surgery and bilateral neck dissections. DESIGN, SETTING, AND PARTICIPANTSThis retrospective case series reviewed the medical records of patients with HPV-related BOT OPSCC who underwent transoral surgery and bilateral neck dissections from January 1, 2002, through December 31, 2018, at the tertiary care center of Washington University School of Medicine in St Louis. Patients had a median follow-up of 30.0 months (interquartile range, 11.0-60.4 months). Patients with recurrent disease or multiple synchronous OPSCC primary tumors were excluded for a total of 89 patients. Data were analyzed from January 1 through June 1, 2019. MAIN OUTCOMES AND MEASURESThe primary outcome was the rate of contralateral occult nodal disease. Secondary outcomes were potential risk factors for contralateral occult nodal disease and regional recurrence rates.RESULTS Eighty-nine patients were included in the series, of whom 81 (91.0%) were men. The mean (SD) age was 60 (9) years. Overall, 34 patients (38.2%) had pathologic contralateral nodal metastases. Seventy patients had no clinical evidence of contralateral nodal disease. Of these 70, occult nodes were identified in 15 (21.4%). Risk of contralateral disease was higher when the primary tumor crossed midline (odds ratio, 6.23; 95% CI, 1.71-22.77). Of the 55 patients with no occult disease identified, only 2 (3.6%) received radiotherapy to the contralateral neck, and no regional recurrence of disease was noted.CONCLUSIONS AND RELEVANCE Given the rate of occult contralateral nodal disease of 21.4%, it appears that contralateral elective neck dissection or radiotherapy should be recommended in patients with HPV-related BOT OPSCC. Patients with a pathologically negative result of contralateral neck dissection may not benefit from radiotherapy to that nodal basin. Future prospective investigations should evaluate functional and oncologic outcomes of contralateral elective neck dissection compared with elective radiotherapy in the contralateral neck for HPV-related BOT OPSCC.

Oncologic outcomes of human papillomavirus–associated oropharynx carcinoma treated with surgery alone: A 12‐institution study of 344 patients

“…In the recently published ORATOR trial, which randomized early‐stage OPSCCs to definitive radiation protocols or definitive surgery with guideline‐based adjuvant treatment, 88% of which were HPV+OPSCC, the recurrence rate (12%), progression‐free survival (PFS; >85%), and OS (>90%) were similar in the 2 arms of the trial and similar to those for our patient cohort treated with surgery alone 23 . Compared with the less than 2% rate of contralateral neck recurrence in our highly selected cohort, the rates of contralateral LN metastases in other studies have been higher at 12% to 21% for patients with BOT HPV+OPSCC 36‐38 . However, these studies included patients with more advanced primary site and nodal disease, which could potentially lead to the higher rates of contralateral metastases.…”

Phase II study of de‐intensified intensity‐modulated radiotherapy and concurrent carboplatin/5‐fluorouracil in lateralized p16‐associated oropharyngeal carcinoma

“…In addition, although all primary subsites were allowed in our study, perhaps due to a selection bias from the treating physicians, 90% of patients in our cohort had tonsillar cancers and only a minority were base of tongue or subsites considered to have bilateral drainage. In fact, the risk of contralateral occult disease with base of tongue tumors was recently reported to be high as 21% 38 . While coverage of level II‐III contralateral nodes with 43.2 Gy and concurrent chemotherapy could potentially sterilize occult, microscopic contralateral disease, the safety of our approach certainly requires further investigation for lesions approaching midline given their small representativity in the current study.…”

“…In fact, the risk of contralateral occult disease with base of tongue tumors was recently reported to be high as 21%. 38 While coverage of level II-III contralateral nodes with 43.2 Gy and concurrent chemotherapy could potentially sterilize occult, microscopic contralateral disease, the safety of our approach certainly requires further investigation for lesions approaching midline given their small representativity in the current study. While consensus guidelines recognize ipsilateral radiotherapy as a standard option for well lateralized T1N0-1 tonsillar tumors, 39 ipsilateral radiotherapy in more advanced regional disease remains a subject of debate.…”

Contralateral nodal spread in human papillomavirus‐associated oropharyngeal cancer: Can more details help guide contralateral neck coverage?

“…This appears consistent with recent data from Last et al who reported almost all contralateral disease to be confined within Levels II and III. 2,3 Was a similar distribution found among the 11 patients with pCND in Smith et al's series? Furthermore, in their six cases where clinical staging predicted pCND, did clinical staging accurately predict the involved levels?…”