ICHNO-ECHNO 2022 - Abstract Book

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ICHNO-ECHNO 2022

specimen, to obtain free margins and reduce the need for adjuvant treatment. We compared these results with a consecutive cohort of conventional treated SCCT patients. Materials and Methods Forty-three consecutive SCCT patients were included in a prospective cohort. During surgery, a 16MHz hockey-stick-shaped probe was used to capture the tumor border and the resection plane in one image (Fig. 1). The distance between the tumor border and resection plane was measured at the anterior, deep central and posterior portion of the resection, while aiming for an echographic margin of 10mm. Immediately after the resection, a 20MHz-probe was used to check the resection margins (Fig. 1). A RR was immediately executed during the same surgery when an inadequate margins was found. The “overall” margin of every patient was determined by calculating the mean of the histopathological margins of the resection specimen at five different locations (i.e. anterior, posterior, medio-cranial, latero-caudal and deep). Resection margins and need for adjuvant treatment of the US-treated cohort were compared with a retrospective cohort of 96 conventionally treated SCCT patients.

Results Free resection margins improved from 18% in the conventionally treated cohort to 51% in the US-treated cohort (P<0.001). The mean overall margin increased from 6.9mm (SD: 2.0mm) in the conventionally treated cohort to 8.8mm (SD: 2.6mm) in the US-treated cohort (p<0.001). The frequency of local adjuvant RTx decreased from 21% in the conventionally treated cohort to only 9% in the US-treated cohort (not statistically significant). The frequency of adjuvant RR was in both cohorts 9%. Conclusion US-guided resections SCCT resections generate more free resection margins, with a minimal increase of resection of healthy tongue tissue. We believe the increase in margin control and the reduction of need for local adjuvant RTx outweighs the resection of 1.9mm healthy tongue tissue. A multicenter randomized controlled trial will be executed to confirm that this new technique yields less adjuvant treatment and a better tongue function and quality of life.

PO-0101 Can anatomical location of head & neck melanoma primaries influence selectivity of neck dissection?

C. Brennan 1 , N. Kelemen 2 , P. Matteucci 2

1 Hull University Hospitals NHS Trust, Department of Plastic Surgery, Hull, United Kingdom; 2 Hull University Hospital NHS Trust, Department of Plastic Surgery, Hull, United Kingdom Purpose or Objective Following the Checkmate 238 and KEYNOTE-054 studies, prognostic benefits of adjuvant immunotherapy in stage III melanoma are evident. Although no longer routinely performed, completion lymphadenectomy (CND) may still be useful for locoregional control in patients with macroscopic disease at initial presentation, or for those who relapse whilst on or following systemic therapy. Selective neck dissection (SND) demonstrates favourable morbidity, but the impact of neck dissection comprehensiveness on prognosis is unclear. We review the link between anatomical location of primary head and