Uptake of sentinel lymph node biopsy following a melanoma diagnosis: an Australian population-based study

Discussion about sentinel lymph node biopsy (SLNB) is recommended for clinical management of patients whose melanomas meet certain criteria, however previous studies have shown relatively low uptake. It is unclear if SLNB uptake has changed over time.

A population-based study using record linkage was conducted in Australia for persons (n = 26,760) with a primary invasive melanoma diagnosis (Breslow thickness ≥0.75 mm) reported to the New South Wales (NSW) Cancer Registry between 2003 and 2018, which were linked to hospital records. We examined whether a SLNB was performed within six months of the melanoma diagnosis and factors that influenced uptake.

Between 2003 and 2018, the annual numbers of melanoma diagnoses and SLNB procedures both increased, while the proportion of patients undergoing SLNB remained stable (between 34% and 39%) over time. The average proportion of patients who received a SLNB during the study period was 36% for those with an invasive melanoma ≥0.75 mm in Breslow thickness, 24% for Breslow thickness 0.75-1.2 mm and 43% for Breslow thickness >1.2 mm. Factors independently associated with uptake included age, Breslow thickness, body site, melanoma subtype, socio-economic status and geographic remoteness.

There was minimal change to the proportion of patients receiving SLNB between 2003 and 2018, with the proportion remaining relatively low despite evolving clinical practice guidelines. Lower uptake among patients living outside major cities and for those with greater socio-economic disadvantage indicates possible inequities in care.