Introduction:

Merkel cell carcinomas (MCCs) are skin cancer predominantly affecting the elderly, who often delay seeking medical opinions for asymptomatic lesions which initially resemble less aggressive skin lesions. This study aims to investigate the direct impact of patient-related delays for seeking medical opinions on clinical outcomes in MCC.

Methods:

A detailed international database was complied, merging anonymous data from 303 MCC patients across Canda, France, and Australia with published individual patient data from an additional 646 cases. The combined databases comprised 949 patients. Descriptive and comparative analyses were performed, focusing on the time interval before patients sought medical opinion and subsequent disease stages at presentation, recurrence rates, and survival.

Results:

Among the 949 patients, a quantifiable time interval before seeking medical evaluation was recorded in 322 (33.9%), with the median being 4 months (range 0-60). Those presenting earlier (shorter than the median delay) and later (longer than the median delay) were compared for initial stages (localized, nodal, or metastatic), recurrence rates, and 5 years overall and cause-specific survival. Statistical analyses including chi-square and log-rank tests were applied. Results indicate that delayed presentation is associated with a trend for advanced-stages disease at diagnosis: 73.6% localized, 21.5% nodal and 3.5% distant disease, versus 82.5% localized, 14.7% nodal and 2.3% distant disease for those with < 4 mos (P=0.09, chi-square test). The rate of disease recurrence in any sites after treatment was 63.9% vs. 62.1% (P=0.74, chi-square test). The 5-year overall survival rates were 30.2% versus 36.1% (P=0.37, log-rank test). The 5-year cause-specific survival rates were 51.6% versus 59.0% (P=0.47, log-rank test).

Conclusion:

Patient delay in seeking medical opinion in MCC may compromise outcomes by predisposing to advanced disease. Urgent strategies to reduce diagnostic delays—such as targeted patient education, improved clinical diagnostic protocols, and early use of biomarkers (e.g., MCC polyomavirus titre)—are crucial.