Merkel Cell Carcinoma in Queensland: Treatment, Incidence and Outcomes Over a 10-Year Period (2012–2021)
May 4, 2026
Journal
Australasian Journal of Dermatology
Publication Date
May 4, 2026
Authors
Merkelcell.org Summary
In Australia, the northeastern state of Queensland has the highest reported rate of Merkel cell carcinoma (MCC) in the world. As of 2010, about 1.61 out of every 100,000 people in Queensland were diagnosed with MCC each year.
In Queensland, most MCC cases are thought to be caused by ultraviolet (UV) damage from the sun. This is different from many MCC cases in the United States, where the Merkel cell polyomavirus (MCPyV) is a more common cause. This study looked at how MCC rates, treatments, and patient outcomes changed in Queensland from 2012 to 2021.
A total of 1,061 patients were diagnosed with MCC in Queensland during this 10-year period. Most patients were male, making up 68% of the group. The median age at diagnosis was 78 years, meaning half of the patients were younger than 78 and half were older. The most common place for MCC to develop was on the head and neck, which accounted for 40% of cases.
At the time of diagnosis, 63% of patients had cancer that was still limited to the original area, called stage I or II disease. Another 25% had cancer that had spread to nearby lymph nodes, called stage III disease. About 5% had cancer that had spread to distant parts of the body, called stage IV disease. About 27% of all patients had a condition that weakened their immune system.
Overall, from 2012 to 2021, the average age-standardized rate of MCC was 1.89 cases per 100,000 people. The rate was higher in men than in women. The authors suggest that this high rate may be related to heavy sun exposure earlier in life, especially before routine use of good sun protection such as sunscreen, hats, and protective clothing.
Most patients were treated with surgery, either alone or together with radiation therapy. Overall, 35% of patients had their MCC come back at some point. Most recurrences happened early: 93% occurred within 3 years after initial MCC diagnosis.
Encouragingly, the risk of death due to MCC fell by 36%. The authors suggest this decrease may be partly due to the use of immunotherapy, a treatment that helps the patient’s own immune system fight cancer.
These findings give helpful information about MCC trends and outcomes in a region where this cancer is especially common, and may help guide future patient care.
Abstract
Background
Merkel Cell Carcinoma (MCC) is a rare skin cancer with aggressive behaviour. We present results for incidence and outcomes of MCC in Queensland, a population having the highest rates of skin cancer worldwide.
Methods
Data for patients diagnosed with MCC between 2012 and 2021 were obtained from the population-based Queensland Oncology Repository. The age-standardised incidence rate trend was assessed using Joinpoint regression. Five-year MCC-specific survival was estimated using the Kaplan–Meier method and factors independently associated with survival were determined from a Fine-Grey multivariable model.
Results
A total of 1061 patients with MCC were included. Median age at diagnosis was 78 years, 68% were male and 27% were immunocompromised. Nearly all patients (94%) received treatment within 365 days of diagnosis, of whom 79% had surgery, 58% had radiotherapy and 15% had intravenous systemic therapy, either alone or in combination with other modalities. The average annual incidence rate was 1.89 per 100,000 population and remained stable over the study period (ptrend = 0.13). Over one-third (35%) of the study cohort developed recurrences within 5 years, with a median time to recurrence of 11 months. Five-year MCC-specific survival increased from 61% between 2012 and 2016 to 69% during 2017–2021 (p = 0.01). Older age at diagnosis, higher tumour stage, a greater number of co-morbidities and immunosuppression were significantly associated with poorer survival.
Conclusion
Our results indicate that the incidence of MCC in Queensland has stabilised following a long period of rapid increases. MCC-specific survival is improving, mostly for more advanced tumours, which is likely attributable to increasing use of immunotherapy.