Won Shik Kim

Feasiblity of transoral robotic hypopharyngectomy for early-stage hypopharyngeal carcinoma.

Conventional surgical approaches for hypopharyngeal carcinomas have a great risk for developing treatment-related morbidity. To minimize this morbidity, hypopharyngectomy by transoral robotic surgery (TORS) was performed, and the efficacy and feasibility of this procedure were evaluated. TORS was performed using da Vinci Surgical Robot (Intuitive Surgical Inc., Sunnyvale, CA) in 10 patients with T1 or T2 pyriform sinus cancer and posterior pharyngeal wall cancer. FK retractor (Gyrus Medical Inc., Maple Grove, MN) was used for transoral exposure of the lesion. A face-up 30-degree endoscope was inserted through the oral cavity and two instrument arms were located in both sides of the endoscope. Pyriform sinus was totally resected as a cone-shape from the vallecular to apex region, and ipsilateral arytenoid cartilage was saved for function preservation. The aryepiglottic fold was resected medially. Laterally, the inner perichondrium of the thyroid cartilage was peeled off after perichondrium was incised horizontally to make sure of the safe margin of antero-lateral portion. The posterior margin is an inferior constrictor muscle of the posterior pharyngeal wall. We evaluated the robotic set up time, robotic operation time, blood loss, surgical margins, swallowing time, decannulation time, and surgery related complications. Transoral robotic hypopharyngectomy was performed successfully in all 10 patients. The mean robotic operation time was 62.4min, and an average of 17.5min was required for the setting of the robotic system. There was no significant perioperative complication in the cases. Swallowing function returned to all patients within 8.3days average. Decannulation was carried out within an average of 6.3days after surgery. Transoral robotic hypopharyngectomy was feasible and ontologically safe technique for the treatment of early hypopharyngeal cancer.

Transoral robotic surgery for hypopharyngeal squamous cell carcinoma: 3-year oncologic and functional analysis

The recent trend in treatment of hypopharyngeal cancer is organ preservation in order to maintain swallowing and speech function as well as improve quality of life. Transoral robotic surgery (TORS) can remove hypopharyngeal lesions successfully without an external incision, preserving physiologic functions of affected organs. However, studies have yet to assess the oncologic and functional results of TORS for the treatment of hypopharyngeal cancer. This prospective study evaluated the oncologic and functional results of TORS for the treatment of hypopharyngeal cancer obtained at our institution over a period of 3 years and confirmed the validity of TORS as a surgical organ-preserving strategy. Between April 2008 and September 2011, 23 patients who were diagnosed with hypopharyngeal cancer underwent TORS for removal of a primary lesion. The da Vinci Robotic system (Intuitive Surgical Inc., Sunnyvale, California) was used to remove the lesion. The Kaplan-Meier method was used to analyze overall survival and disease-free survival. Videopharyngogram study (VEF) was performed and functional outcome swallowing scale (FOSS) was utilized to measure and evaluate swallowing function. Acoustic wave form analysis was conducted to evaluate voice status. Overall survival at 3 years was 89% and disease-free survival was 84%. On the VEF study, serious aspiration or delay of swallowing was not observed during the pharyngeal stage of the swallowing process. Overall, 96% of the patients showed favorable swallowing abilities with an FOSS score ranging from 0 to 2. The fundamental frequency variation (vF0) and jitter were increased upon acoustic waveform analysis (vF0=2.71 ± 0.063, Jitter=2.01 ± 0.034), but the harmonic-to-noise ratio (HNR) and shimmer were maintained close to the normal range (HNR=1.28 ± 0.001, Shim=1.74 ± 0.036). The oncologic and functional results of TORS were quite acceptable for the treatment of hypopharyngeal cancer. TORS is a valid treatment option as a surgical, organ-preserving strategy for select patients with hypopharyngeal cancer.

Feasibility of Robot-Assisted Neck Dissections via a Transaxillary and Retroauricular (“TARA”) Approach in Head and Neck Cancer: Preliminary Results

BackgroundRecently, robot-assisted neck dissection in thyroid cancer patients with lateral neck node metastasis has been demonstrated to be feasible. We realized the necessity of technical modification in order to apply robotic system to comprehensive neck dissection for head and neck squamous cell carcinoma. This study examined the feasibility and safety of transaxillary and retroauricular (“TARA”) approach for robotic neck dissection in patients with head and neck squamous cell cancer.MethodsFour human cadaveric dissections were followed by robotic neck dissections in seven patients with oral cavity or laryngopharyngeal cancer through TARA incision.ResultsIn all cases, vital structures including major vessels and nerves were preserved. The numbers of retrieved lymph nodes in robotic neck dissections were comparable with those in conventional neck dissections.ConclusionsRobotic neck dissection via TARA approach is a feasible and useful method with excellent cosmetic results for treating nodal metastasis in selected cases of head and neck squamous cell cancer.

Oncological and functional outcomes of transoral robotic surgery for oropharyngeal cancer

In this prospective study we analysed the oncological and functional results of transoral robotic surgery (TORS) to find out if it was suitable as a minimally invasive treatment for oropharyngeal cancer. Between April 2008 and September 2011, 39 patients with oropharyngeal cancer were treated by TORS. We assessed overall and disease-free survival by the Kaplan-Meier test, and we used videopharyngography and the functional outcome swallowing scale (FOSS) to evaluate swallowing. We used nasometry to estimate hypernasality, and acoustic waveform analysis to evaluate the voice. Thirty-seven patients (95%) had histologically clear margins of resection. Overall survival at 2 years was 96% and disease-free survival 92%. An oral diet was tolerable after a mean of 6 (range 1-18) days. No serious swallowing difficulties were seen on the videopharyngogram. Thirty-six of 38 patients could swallow well (97%) with FOSS scores ranging from 0 to 2 (1 patient had a poor score but was able to take an oral diet after postural training). Voices were maintained close to the normal range on the acoustic waveform analysis. The oncological and functional results of TORS were quite acceptable for the treatment of oropharyngeal cancer. TORS is a valid treatment for selected patients with oropharyngeal cancer.

Robot-Assisted Selective Neck Dissection via Modified Face-lift Approach for Early Oral Tongue Cancer: A Video Demonstration

Recently, early-stage oral cavity cancers are successfully resected via a transoral approach. Nodal metastasis is a crucial factor in determining the survival of oral cavity cancer patients. However, elective neck dissection in earlystage oral cavity cancers is a still controversial procedure. In recent period, in an attempt to hide the cervical scars, robotic modified neck dissection via a transaxillary approach has been introduced by Kang et al. in thyroid cancer with neck metastasis. However, there are limitations to dissect the upper neck level including level I via transaxillary approach. Therefore, we demonstrate our novel technique for robot-assisted neck dissection (RAND) for level I, II, and III via modified face-lift approach (MFLA) and show the pitfalls of the operation, as well as tips for its successful completion.

Surgical techniques and treatment outcomes of transoral robotic supraglottic partial laryngectomy.

The objective of this prospective study was to confirm the validity of transoral robotic supraglottic partial laryngectomy as a conservation surgery for treating supraglottic cancer.

Robot-Assisted Selective Neck Dissection of Levels II to V via a Modified Facelift or Retroauricular Approach

Objectives We performed robot-assisted selective neck dissection via a modified facelift or retroauricular approach without creating an apparent scar around the neck to remove neck node of levels II to V after transoral robotic surgery of a primary lesion in patients with laryngopharyngeal carcinoma. Patient data were prospectively analyzed to verify the feasibility and efficacy of robot-assisted neck dissection in the treatment of cN0 laryngopharyngeal carcinoma. Study Design Prospective case series. Setting University tertiary care facility. Subjects and Methods Between March 2011 and March 2012, 7 patients were enrolled in the study. Before study initiation, the Institutional Review Board of Yonsei University approved the protocol, and informed consent was obtained from all patients. Results Robot-assisted neck dissection was successfully performed in all patients. Five patients underwent selective neck dissection including levels II to IV, and 2 patients underwent selective neck dissection including levels II to V. The average number of lymph nodes retrieved was 25.1. Occult nodal metastasis was found in 1 (14%) neck specimen. During the follow-up period (mean of 13.5 months), all patients were alive without locoregional recurrence. All patients were extremely satisfied with their cosmetic results. Conclusion Robot-assisted selective neck dissection is a feasible and safe technique to manage the neck in cN0 laryngopharyngeal carcinoma patients. It may be especially helpful for patients undergoing transoral robotic surgery since no apparent scar around the neck remains. Long-term results with respect to oncologic safety and functional outcomes are required to establish the validity of robot-assisted neck dissection.

How to optimize laryngeal and hypopharyngeal exposure in transoral robotic surgery

OBJECTIVE The aim of this study was to present the various strategies adopted in our center to improve and overcome problems with exposure of the operative field in 48 patients who underwent TORS for the treatment of laryngeal and hypopharyngeal cancer. METHODS We present our operative and preoperative treatment protocols for patients undergoing TORS for laryngeal and hypopharyngeal cancer. In particular, we emphasize the role of preoperative exposure assessment and the usefulness of simple measures to overcome problems with exposure of the operative field. RESULTS In 12 patients (25%), we experienced difficult laryngeal-hypopharyngeal exposure. However the correct positioning of the robotic arms, the proper use of the laryngeal and tongue blade and some simple maneuvers, such as the anterior traction of the tongue and the partial epiglottectomy, ensured the feasibility of TORS with negative margins in all patients. CONCLUSION In TORS, the exposure of larynx and hypopharynx can be difficult, but the adoption of certain methods may make it possible in most patients. An accurate preoperative evaluation under general anesthesia is the primary strategy for reducing the number of cases terminated intraoperatively. Currently, TORS is not feasible in all patients, but in our opinion, reductions in the size of robotic equipment and development of new devices will extend the application of TORS to a larger number of patients.

Hypoxia Induces Epithelial-Mesenchymal Transition in Follicular Thyroid Cancer: Involvement of Regulation of Twist by Hypoxia Inducible Factor-1α.

Purpose Although follicular thyroid cancer (FTC) has a relatively fair prognosis, distant metastasis sometimes results in poor prognosis and survival. There is little understanding of the mechanisms contributing to the aggressiveness potential of thyroid cancer. We showed that hypoxia inducible factor-1α (HIF-1α) induced aggressiveness in FTC cells and identified the underlying mechanism of the HIF-1α-induced invasive characteristics. Materials and Methods Cells were cultured under controlled hypoxic environments (1% O2) or normoxic conditions. The effect of hypoxia on HIF-1α, and epithelial-to-mesenchymal transition (EMT) related markers were evaluated by quantitative real-time PCR, Western blot analysis and immunocytochemistry. Invasion and wound healing assay were conducted to identify functional character of EMT. The involvement of HIF-1α and Twist in EMT were studied using gene overexpression or silencing. After orthotopic nude mouse model was established using the cells transfected with lentiviral shHIF-1α, tissue analysis was done. Results Hypoxia induces HIF-1α expression and EMT, including typical morphologic changes, cadherin shift, and increased vimentin expression. We showed that overexpression of HIF-1α via transfection resulted in the aforementioned changes without hypoxia, and repression of HIF-1α with RNA interference suppressed hypoxia-induced HIF-1α and EMT. Furthermore, we also observed that Twist expression was regulated by HIF-1α. These were confirmed in the orthotopic FTC model. Conclusion Hypoxia induced HIF-1α, which in turn induced EMT, resulting in the increased capacity for invasion and migration of cells via regulation of the Twist signal pathway in FTC cells. These findings provide insight into a possible therapeutic strategy to prevent invasive and metastatic FTC.

Robot-assisted versus endoscopic submandibular gland resection via retroauricular approach: a prospective nonrandomized study

The aim of this study was to compare the short-term clinicopathological results of robot-assisted and endoscopic resection of the submandibular gland by the retroauricular approach. We present a prospective, non-random, study of 35 patients who had endoscope-assisted (n=22), or robot-assisted (n=13), resection of the submandibular gland using a retroauricular approach. Patients selected one of the two methods, and short-term clinical outcomes were then compared, including maximum diameter of the tumour and gland, length of incision, total operating time, amount of operative bleeding, amount and duration of drainage, duration of hospital stay, cosmesis, and complications. The operation was feasible in all patients with no appreciable operative complications or need to convert to a conventional open operation. The operating time of the robot-assisted group (63.4 (6.3)min) was comparable with that of the endoscopic group (66.5 (9.1)min) (p=0.15). There were no differences in the other clinical outcomes between the 2 groups. Both groups of patients were extremely satisfied with their postoperative cosmesis, and did not differ significantly (p=0.89). Robotic and endoscopic resection of the submandibular gland gave comparable early surgical outcomes and excellent cosmetic results. Despite the technical convenience for the surgeon, the robot gave no apparent clinical benefit over the endoscope in this series.