Faculty Bibliography

INTRODUCTION/BACKGROUND:Transoral resection of pharyngeal tumors with acceptable oncological and functional results can be challenging due to their location in a narrow anatomic space. CASE PRESENTATION/METHODS:In this case report, we demonstrate successful visualization and resection of a squamous cell carcinoma of the oropharynx using the novel Medrobotics(®) Flex(®) System. The Medrobotics(®) Flex(®) System (Medrobotics Corp., Raynham, MA, USA) is an operator controlled flexible endoscope system that includes a rigid endoscope and computer-assisted controllers, with two external channels for the use of compatible, 3.5mm flexible instruments. DISCUSSION/CONCLUSIONS:In a 74-year old female patient a T1 squamous cell carcinoma of the oropharynx was visualized and completely resected using this system. The Medrobotics(®) Flex(®) System is a promising device for transoral approaches in resection of tumors within the pharynx. CONCLUSION/CONCLUSIONS:Good visualization, access, and flexibility of the endoscope and instruments are hereby clear advantages of the system compared to commonly used systems.

The human communicating nerve (HCN) is a connection between the superior and recurrent laryngeal nerves that has been described in cadaveric studies. We report a case of an extralaryngeal variant of the HCN that was identified and stimulated intraoperatively during thyroidectomy. This appears to be the first case of intraoperative identification of this anatomic variant, of which the functional significance remains unclear.

The objective of this study is to establish normative waveform data for the external branch of the superior laryngeal nerve (SLN) utilizing laryngeal surface electrodes and intraoperative neurophysiological monitoring (IONM) in conjunction with a clinical neurophysiologist. A retrospective chart review of 91 consecutive at-risk SLN were identified in 51 patients in whom IONM using laryngeal surface electrodes was performed by a clinical neurophysiologist using Dragonfly (Neurovision Medical Products, Ventura, CA) recording electrodes and a Protektor (Natus Medical Inc., San Carlos, CA)16 channel- intraoperative nerve monitoring system. Inclusion criteria were met for 30 SLN. Data collected included preoperative diagnosis, surgical procedure, rates of nerve identification and stimulation, and waveform characteristics. Waveform analysis for 30 SLN yielded a peak latency of 4.0 ± 0.2 ms, onset latency 2.3 ± 0.1 ms, peak-to-peak amplitude of 220.4 ± 31.1 µV, onset-to-peak amplitude of 186.0 ± 25.0 µV, and stimulation current threshold of 0.55 ± 0.03 mA (data = mean ± SEM). Two patients had abnormal SLN function documented clinically on postoperative laryngoscopic examination. Laryngeal surface electrodes were successfully utilized to identify and monitor SLN function intraoperatively. IONM using laryngeal surface electrodes enables analysis of waveform morphology and latency in addition to threshold and amplitude data obtained with the traditional NIM system, potentially improving the performance of nerve monitoring during thyroid surgery.

IMPORTANCE/OBJECTIVE:Positive margins are associated with poor prognosis among patients with oral tongue squamous cell carcinoma (SCC). However, wide variation exists in the margin sampling technique. OBJECTIVE:To determine the effect of the margin sampling technique on local recurrence (LR) in patients with stage I or II oral tongue SCC. DESIGN, SETTING, AND PARTICIPANTS/METHODS:A retrospective study was conducted from January 1, 1986, to December 31, 2012, in 5 tertiary care centers following tumor resection and elective neck dissection in 280 patients with pathologic (p)T1-2 pN0 oral tongue SCC. Analysis was conducted from June 1, 2013, to January 20, 2015. INTERVENTIONS/METHODS:In group 1 (n = 119), tumor bed margins were not sampled. In group 2 (n = 61), margins were examined from the glossectomy specimen, found to be positive or suboptimal, and revised with additional tumor bed margins. In group 3 (n = 100), margins were primarily sampled from the tumor bed without preceding examination of the glossectomy specimen. The margin status (both as a binary [positive vs negative] and continuous [distance to the margin in millimeters] variable) and other clinicopathologic parameters were compared across the 3 groups and correlated with LR. MAIN OUTCOMES AND MEASURES/METHODS:Local recurrence. RESULTS:Age, sex, pT stage, lymphovascular or perineural invasion, and adjuvant radiation treatment were similar across the 3 groups. The probability of LR-free survival at 3 years was 0.9 and 0.8 in groups 1 and 3, respectively (P = .03). The frequency of positive glossectomy margins was lowest in group 1 (9 of 117 [7.7%]) compared with groups 2 and 3 (28 of 61 [45.9%] and 23 of 95 [24.2%], respectively) (P < .001). Even after excluding cases with positive margins, the median distance to the closest margin was significantly narrower in group 3 (2 mm) compared with group 1 (3 mm) (P = .008). The status (positive vs negative) of margins obtained from the glossectomy specimen correlated with LR (P = .007), while the status of tumor bed margins did not. The status of the tumor bed margin was 24% sensitive (95% CI, 16%-34%) and 92% specific (95% CI, 85%-97%) for detecting a positive glossectomy margin. CONCLUSIONS AND RELEVANCE/CONCLUSIONS:The margin sampling technique affects local control in patients with oral tongue SCC. Reliance on margin sampling from the tumor bed is associated with worse local control, most likely owing to narrower margin clearance and greater incidence of positive margins. A resection specimen-based margin assessment is recommended.

Head and neck squamous cell carcinoma (HNSCC) has a variety of causes. Recently, the human papilloma virus (HPV) has been implicated in the rising incidence of oropharyngeal cancer and has led to variety of studies exploring the differences between HPV-positive and HPV-negative HNSCC. The calcium-activated chloride channel TMEM16A is overexpressed in a variety of cancers, including HNSCC, but whether or not it plays different roles in HPV-positive and HPV-negative HNSCC is unknown. Here, we demonstrate that TMEM16A is preferentially overexpressed in HPV-negative HNSCC and that this overexpression of TMEM16A is associated with decreased patient survival. We also show that TMEM16A expression is decreased in HPV-positive HNSCC at the DNA, RNA, and protein levels in patient samples as well as cell lines. We demonstrate that the lower levels of TMEM16A expression in HPV-positive tumors can be attributed to both a combination of copy number alteration and promoter methylation at the DNA level. Additionally, our cellular data show that HPV-negative cell lines are more dependent on TMEM16A for survival than HPV-positive cell lines. Therefore, we suspect that the down-regulation of TMEM16A in HPV-positive HNSCC makes TMEM16A a poor therapeutic target in HPV-positive HNSCC, but a potentially useful target in HPV-negative HNSCC.

IMPORTANCE/OBJECTIVE:Few studies have examined quality-of-life (QOL) outcomes in patients who undergo transoral robotic surgery (TORS) alone (ie, without adjuvant radiotherapy or chemoradiotherapy). OBJECTIVE:To report QOL outcomes of patients with oropharyngeal squamous cell carcinoma who receive only TORS. DESIGN, SETTING, AND PARTICIPANTS/METHODS:Medical records for all patients undergoing TORS for treatment of primary oropharyngeal squamous cell carcinoma from May 1, 2010, to March 31, 2014, at a tertiary care academic cancer center were examined from June through September 2014. Thirty-four patients who did not receive adjuvant therapy after TORS were included in the study. INTERVENTION/METHODS:Primary surgical resection via TORS. MAIN OUTCOMES AND MEASURES/METHODS:The University of Washington Quality of Life, version 4, questionnaire was completed by patients preoperatively and at 1-, 6-, 12-, and 24-month intervals after TORS. Demographic, clinicopathologic, and follow-up data were collected. RESULTS:Mean follow-up time was 14 months (May 1, 2010, to April 30, 2014). Most patients had T1 (20 [59%]) or T2 (13 [38%]) and N0 (13 [38%]) or N1 (16 [47%]) disease. Statistically significant improvement in QOL outcomes was noted in the following postoperative domains: chewing from 1 month (median, 50 [IQR, 50-100]) to 12 months (100 [IQR, 100-100]; P = .048), swallowing from 1 month (70 [IQR, 30-85]) to 6 months (100 [IQR, 70-100]; P = .047) and 1 to 24 months (100 [IQR, 70-100]; P = .048), pain from 1 month (38 [IQR, 25-75]) to 6 months (88 [IQR, 75-100]; P = .006) and 1 to 12 months after surgery (100 [IQR, 75-100]; P = .01), and activity from 1 month (63 [IQR, 50-88]) to 24 months (100 [IQR, 75-100]; P = .03). Two participants (6%) died during the follow-up period: 1 because of disease and 1 because of a myocardial infarction. Two patients (6%) required temporary gastrostomy tube placement, but none required tracheostomy. CONCLUSIONS AND RELEVANCE/CONCLUSIONS:Appropriately selected patients who undergo TORS alone for oropharyngeal squamous cell carcinoma experience acceptable short- and long-term QOL outcomes.

OBJECTIVES/HYPOTHESIS/OBJECTIVE:Adenosquamous carcinoma (ASC) is a rare variant of head-and-neck squamous cell carcinoma (HNSCC) generally thought to be uniformly aggressive with poor prognosis. However, it remains unknown how overall survival compare with conventional HNSCC. Here we report for the first time that ASC does not necessarily indicate a worse prognosis than conventional HNSCC. STUDY DESIGN/METHODS:Case-control retrospective study. METHODS:Forty-two primary tumors of the head and neck, treated with curative intent, were identified. Next, 2:1 matching of HNSCC was performed using the following matching criteria: gender, site, pathologic tumor stage, and pathologic node stage. Successful matching was performed for 32 of 42 tumors. Additionally, 20 samples were sent for break-apart FISH testing to evaluate for the presence of the CRTC1-MAML2 translocation. RESULTS:There was a 1.8:1 male to female ratio, with a mean age of 62 years (range 38-84). The layrnx was the most common site (26%), followed by oropharynx (24%), oral cavity (19%), and sinonasal (17%). Kaplan-Meier analysis of adenosquamous and matched HNSCC showed similar survival curves. Median survival times for ASC and HNSCC were 4 and 6 years, respectively. A random-effects Cox model with Gamma frailty revealed no statistical difference between the two groups (P=0.25). All cases of ASC were negative for the CRTC1-MAML2 translocation. CONCLUSION/CONCLUSIONS:This study directly compares primary ASC with HNSCC. No difference in overall survival was detected in contradistinction to the previously thought uniformly poor prognosis. We also highlight the importance of the CRTC1-MAML2 translocation in distinguishing ASC from mucoepidermoid carcinoma. LEVEL OF EVIDENCE/METHODS:3b.