Faculty Bibliography

OBJECTIVES/HYPOTHESIS/OBJECTIVE:Using human cadavers, we investigated the feasibility of using a new robotic platform, the Medrobotics Flex System, for laryngeal access and flexible tool delivery to facilitate the performance of pharyngolaryngeal procedures without laryngeal suspension. Our initial trials specifically assess the utility of this experimental robotic system for epiglottectomy and base of tongue resection. STUDY DESIGN/METHODS:Feasibility; Level of evidence: NA. METHODS:Using standard mouth retractors, the Flex™robot was driven via the physician controller to the supraglottic region. Non-crossing, flexible endoscopic tools were inserted through the robot's external tool channels to retract, cauterize, and remove tissue in each procedure type. Mock surgical procedures were performed on the laryngopharyngeal complex including epiglottectomy, base of tongue resection, and vocal cord excision. Time-to-tissue exposure was noted for each procedure. Each epiglottectomy was timed to determine operation duration. RESULTS:Epiglottectomy, base of tongue resection, and vocal cord excision were successfully performed without suspension laryngoscopy. Individual surgeons improved the procedure time significantly (P = 0.03) between first and second attempts. Epiglottectomies were performed in an average time of 42 minutes (N = 5, σ = 28 minutes). CONCLUSIONS:The Medrobotics Flex System demonstrates great potential as a surgical tool in head and neck oncology. Compared to other surgical robots, the Flex System offers facilitated access, vision, and triangulation of flexible tools for procedures in the endolarynx. LEVEL OF EVIDENCE/METHODS:N/A.

UNLABELLED:OBJECTIVES/HYPOTHOSES: TORS (Trans Oral Robotic Surgery) has been demonstrated to be an acceptable alternative to chemoradiation for the treatment of early stage malignant lesions of the oropharynx, with equivalent tumor control and enhanced functional outcomes. Surgical ablation of tumors of the oropharynx under conditions of limited access, however, creates the need to adapt the robotic platform to surgical reconstruction and to assess reconstructive outcomes. We present our experience with the Facial Artery Musculomucosal (FAMM) flap with robotic assistance for the reconstruction of defects of the soft palate. METHODS:We reviewed the records of five patients who underwent combined robot-assisted resection of malignant lesions of the oropharynx with immediate reconstruction. The reconstructions included four ispilateral and one bilateral FAMM flaps. Patients were assessed for complications and functional results. RESULTS:Successful closure of the defect was achieved in all five patients. There were no major complications; however, three patients developed minor wound dehiscence and two were revised at the time of planned subsequent lymphadenectomy. All five patients achieved a good functional outcome. CONCLUSIONS:The FAMM flap is reliable and easy to raise and transfer, with the surgical robot making it a good candidate for reconstruction of moderate-sized defects created by TORS applied to malignancies of the soft palate. Minor wound dehiscence is not infrequent, but reconstructive outcomes are nevertheless good. A unilateral FAMM flap will reach to the contralateral border of the uvula and is best limited to defects with a width of 2 cm or less.

The development of robotic surgery has brought new levels of precision and control to minimally invasive surgical techniques. Its effectiveness, well established in urologic and gynecologic surgery applications, has also been demonstrated in cardiac, endocrine and general surgery. Recently, trans-oral robotic approaches to oropharyngeal tumor resection have been reported and, by eliminating the need for morbid lip and mandible splitting approaches, trans-oral robotic surgery (TORS) has allowed a re-assessment of surgical options for early stage tumors which have until recently been treated primarily with chemoradiation. The application of the TORS approach to malignant and non-malignant conditions affecting the oropharynx has created the need to develop robotic-assisted methods of managing the resultant tissue defects and to assess and compare the effectiveness of these procedures. This report details our early experience with the use of robotic surgery for management of soft tissue defects of the oropharynx in 12 patients.

OBJECTIVES/HYPOTHESIS/OBJECTIVE:In 2% to 3% of patients with cancer metastatic to cervical lymph nodes, a primary tumor will not be found despite exhaustive diagnostic efforts. The treatment for these patients includes cervical lymphadenectomy followed by radiation to areas with increased risk of harboring a mucosal primary. Wide-field radiation therapy increases the incidence of xerostomia and dysphagia. Localizing a primary tumor has thus both therapeutic and quality-of-life implications, allowing possible complete surgical excision, concentrated radiation therapy, and potential deintensification of adjuvant therapy. With improved visualization and freedom of motion, transoral robotic surgery (TORS) is an innovative surgical modality that allows resection of oropharyngeal subsites with minimal morbidity. STUDY DESIGN/METHODS:Retrospective chart review. METHODS:Ten patients with unknown primary tumors of the head and neck were identified. All patients underwent a cervical biopsy, positron-emission tomography/computed tomography, formal endoscopy, and bilateral tonsillectomy. When the initial endoscopy and biopsies did not localize a primary tumor, all patients underwent transoral robotic base of tongue resection. RESULTS:Evaluation of the patients' oropharyngeal mucosa using the robot did not reveal an obvious lesion and no palpable tumors were appreciated in the resected specimens. In 9/10 (90%) patients, pathologic examination revealed invasive squamous cell carcinoma (SCCA) with a mean diameter of 0.9 cm. CONCLUSIONS:Unknown primary SCCA presents a diagnostic challenge to the head and neck surgeon. We present a small series of tumors that would have been treated as unknown primaries under traditional diagnostic and therapeutic algorithms. TORS base of tongue resection identified primary tumors in 90% patients with minimal morbidity.

The epidermal growth factor receptor (EGFR) signaling pathway is frequently dysregulated in a variety of human malignancies. As a result, agents have been developed to selectively inhibit the tyrosine kinase function of EGFR (EGFR-TKI) for cancer therapy. However, the clinical efficacy of these drugs to date has been limited by both acquired and intrinsic resistance. Macroautophagy, a process of intracellular proteolysis, has been shown to be activated in response to EGFR targeted therapy. However, the specific role of the induction of autophagy remains controversial. Here we show that autophagy is induced in a dose-dependent manner by in vitro treatment of multiple cancer cell lines with EGFR-TKI. Additionally, we find that in cells highly resistant to EGFR-TKI, autophagy is not robustly activated and that co-treatment of these cells with rapamycin, a known inducer of autophagy, can partially restore sensitivity to EGFR-TKI. Finally, we demonstrate that, in resistant cell lines, EGFR-TKI sensitivity can be further inhibited by siRNA-mediated depletion of the critical autophagy protein ATG7. Thus, our data suggests that defective autophagy may be an EGFR-TKI resistance mechanism and that activation of autophagy may be a viable strategy to augment the cytotoxic effect of EGFR-TKIs.

OBJECTIVE:To show that sialoendoscopy is both a safe and effective alternative to traditional treatments for juvenile recurrent parotitis and sialolithiasis. DESIGN/METHODS:Retrospective medical chart review. SETTING/METHODS:Two major pediatric tertiary care centers. PATIENTS/METHODS:Eighteen pediatric patients. INTERVENTIONS/METHODS:A total of 33 sialendoscopic procedures on 27 glands. MAIN OUTCOME MEASURES/METHODS:Indications for surgery, age at onset of symptoms, age at procedure, sex, intraoperative findings, complications, recurrences, need for additional procedures, and follow-up interval. RESULTS:Juvenile recurrent parotitis was the most common indication for sialendoscopy (12 of 18) followed by sialolithiasis (4 of 18). Ten of 12 patients with juvenile recurrent parotitis were asymptomatic after 1 or 2 sialendoscopies (8 patients and 2 patients, respectively). There were 6 minor complications. Three patients ultimately required gland excision for disease management. CONCLUSION/CONCLUSIONS:Sialoendscopy is safe and effective as a treatment for pediatric salivary gland disorders.

The surgical robot has been demonstrated to have useful applications in urologic, gynecologic, cardiac, general, and endocrine surgery. The development of robotic surgery has enhanced the precision and control of the surgeon in minimally invasive surgical situations specific to these specialties and, more recently, has been applied to the treatment of oropharyngeal tumors in the form of transoral robotic surgery (TORS). The elimination of the need for lip- and mandible-splitting approaches has allowed a reassessment of surgical options for the treatment of tumors that have until recently been primarily addressed nonoperatively with chemoradiation. The TORS approach has created the need to adapt current reconstructive options to robotic technology to manage the resultant tissue defects and to assess and compare the effectiveness of these procedures. This report details our early experience with the use of robot-assisted free tissue transfer for management of soft tissue defects of the oropharynx.