Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2019

An International Randomised Trial of Post-operative Radiation Therapy Following Wide Excision of Neurotropic Melanoma of the Head and Neck (#280)

Matthew Foote 1 , Mark Smithers 1 , Angela Hong 2 3 , Gerald Fogarty 2 3 , Richard Scolyer 3 4 , Elizabeth Paton 5 , Christopher Barker 6 , Margaret Chua 7 , Kerwin Shannon 3 , Bryan Burmeister 8 , Jenny Nobes 9 , Narelle Williams 10 , Junya Eguchi 5
  1. Princess Alexandra Hospital, Brisbane, QLD
  2. Genesis Cancer Care, Mater Sydney Hospital, Sydney, NSW, Australia
  3. Melanoma Institute Australia, Sydney, NSW, Australia
  4. Royal Prince Alfred Hospital, Sydney, NSW
  5. Melanoma and Skin Cancer Trials, North Sydney, NSW, Australia
  6. Memorial Sloan Kettering Cancer Centre, New York, USA
  7. Peter MacCallum Cancer Centre, Melbourne, VIC
  8. Genesis CancerCare Fraser Coast, Urraween, QLD
  9. Norfolk and Norwich University Hospital, Norfolk, UK
  10. Princess Alexandra Hospital , Brisbane, QLD

Neurotropic melanoma is a rare subtype of cutaneous melanoma that is often associated with a higher local relapse rate. Neurotropism in melanoma has a higher incidence in the head and neck region. Currently there is no effective treatment for resected neurotropic melanoma. Uncontrolled studies suggest that radiation therapy (RT) may reduce the risk of local relapse but there are no randomised trials to confirm this hypothesis.

The primary objective of the study is to compare the rate and timing of local relapse between RT treatment and observation. Secondary objectives including difference in relapse-free survival, time to relapse, overall survival, patterns of relapse, late toxicity, and quality of life.

This is a two-arm multicentre prospective trial that is currently recruiting patients from 15 national and 5 international sites (in UK, USA and Slovenia). Patients are randomised in the ratio of 1:1 between RT (48 Gy in 20 fractions) and observation. Quality assurance for surgery, radiotherapy and pathology is being undertaken. 100 patients are required to detect a hazard ratio of 0.437, corresponding to 3-year local relapse-free rates of 65% and 83% in the observation and RT arms, respectively. The expected duration is 10 years accrual with a follow-up period of 5 years. Currently, 46 patients have been randomised.

This is an ambitious trial that is unlikely to be replicated and therefore requires effective collaboration nationally and internationally to achieve the target recruitment.