Learning curve for the combined trans-oral and chest approach to endoscopic selective neck dissection: a cumulative sum (CUSUM) analysis

Background: The combined trans-oral and chest approach is a novel technique for endoscopic selective neck dissection (SND), with satisfactory oncological safety and cosmetic results. However, this hybrid approach is difficult, and the learning curve remains unclear. In this study, we aimed to evaluate the short-term outcomes for this hybrid approach, and to define the associated learning curve.

Method: Clinical data and surgical outcomes of 58 PTC patients who underwent endoscopic SND via combined trans-oral and chest approach between September 2020 and April 2023 were retrospectively reviewed. The cumulative sum (CUSUM) sequential analysis technique is used to detect change, and has been applied for the evaluation of learning curves.

Results: The study population included 58 patients (40 females, 18 males), with mean age of 38.9 ± 12.7 years and average body mass index of 22.6 ± 4.8 kg/m². In all cases, the same surgical team performed endoscopic SND via combined trans-oral and chest approach. The numbers of positive/retrieved lymph nodes were 4.3 ± 3.2/27.8 ± 8.4 in the lateral compartment and 4.0 ± 3.5/8.4 ± 5.1 in the central compartment. The learning curve was evaluated in terms of an initial phase (20 cases) and a mature phase (38 cases). Operative time was longer during the initial phase, compared to the mature phase (375.2 vs. 274.6 min, p = 0.002). The frequency of operative complications was higher during the initial phase, compared to the mature phase (85% vs. 55.3%, p = 0.048).

Conclusions: After the experience acquired using endoscopic SND via combined trans-oral and chest approach to treat PTC in 20 patients, the number of complications decreased significantly. Compared to data collected for the initial phase, data collected for the mature phase showed trends toward decreased operating time.