A new study has found the rates of cutaneous squamous cell carcinoma (cSCC) are significantly higher than previously reported in coastal southern NSW – leading to a call to reconsider Australia’s management of keratinocyte cancers.
The findings support other calls for national registration of non-melanoma skin cancers, as reported recently in the limbic.
The NSW study accessed data from public and private histopathology laboratories to report 11, 712 cSCCs over the 4-year period from 2016 to 2019 within the Illawarra, Shoalhaven, Southern Highlands and Eurobodalla regions.
The average age for men with a cSCC diagnosis was 74.3 years and 75.8 years for women.
The study, published in the Australasian Journal of Dermatology, found men were diagnosed with cSCC 1.64 times as often as women.
Matched to population data from the ABS, the age-adjusted annual incidence rate of cSCC was calculated at 777.3/106/year for the population over 20 years of age.
“The greatest rate was for men >60 years with an incidence of 2875/106/year,” it said. “For women >60 years, the incidence was 1530/106/year.”
“The incidence of primary cSCC in coastal southern NSW is extremely high,” the study said.
“These rates of cSCC are more than four times greater than previously published data, whether registry-based, from surveys and by Medicare billing as a method for estimating incidence.”
The study, led by Dr Anna Wilson with senior investigator Associate Professor Bruce Ashford from the Wollongong Hospital’s Division of Surgery, said the relative risk of developing a primary cSCC was greatest in the southern and coastal regions for patients >60 years.
“This was not the case for those 40–60 years, where further inland saw the greatest relative risk. This analysis over larger areas would offer detailed information for education, early intervention and targeted surveillance in cSCC.”
They said the findings provide the best estimate of the true incidence of primary cSCC in mainland Australia.
“It identifies a rate far in excess of that previously published or understood. It also highlights the challenges in ad hoc analysis of incidence in the absence of routine notification of cSCC.”
“This study provides a platform for rediscussing the wisdom of excluding keratinocyte cancer from mainland state cancer registries,” the investigators concluded.
“We propose that a method and agency for collecting these data nationally would allow for the appropriate resourcing of efforts to both prevent and manage cSCC in our communities.