Objective:

To analyze incidence trends of cutaneous squamous cell carcinoma (cSCC), carcinoma in situ, and keratoacanthoma (KA) in Denmark from 2005 to 2023, highlighting the significance of these trends for public health.

Key Findings:

• By 2023, age-standardized incidence rates for cSCC were 131.6 per 100,000 in males (annual increase of 2.6%) and 77.7 in females (annual increase of 3.1%).
• Carcinoma in situ incidence rates increased significantly, with 89.4 per 100,000 in males (annual increase of 6.4%) and 78.6 in females (annual increase of 5.8%) by 2023.
• KA incidence declined, reaching approximately 28 per 100,000 person-years in both sexes (annual decrease of 1.2% in males and 0.8% in females).

Interpretation:

The study indicates a notable increase in the incidence of cSCC and carcinoma in situ, particularly among younger populations, while KA incidence is decreasing, suggesting a need for targeted public health interventions.

Limitations:

• Restriction to histologically confirmed lesions may underestimate overall incidence, as some lesions may be managed without biopsy.
• Changes in diagnostic practices and surveillance may influence observed trends, potentially skewing data.
• First per-person diagnoses do not reflect the total tumor burden in patients with multiple lesions, limiting the understanding of disease impact.

Conclusion:

The findings highlight the rising incidence of cutaneous malignancies, emphasizing the need for increased awareness and potential changes in management strategies, including enhanced screening and preventive measures.