Merkel cell carcinoma in Turkey: A multicentric study

Area of Science:

• Oncology
• Dermatology
• Epidemiology

Background:

• Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine skin cancer.
• Understanding MCC's characteristics and outcomes in specific populations is crucial for improving patient care.

Purpose of the Study:

• To evaluate the clinicopathologic features of MCC cases in Turkey.
• To assess treatment outcomes and survival rates for MCC patients in Turkey.

Main Methods:

• Retrospective analysis of 89 MCC patients diagnosed between 1999 and 2018 across 20 Turkish centers.
• Evaluation of patient and tumor characteristics, alongside adjuvant and metastatic treatment outcomes.

Main Results:

• The majority of patients (85.4%) were diagnosed at a localized stage, with lower limbs being the most common primary site.
• Two-year disease-free survival was 68.1% and 5-year DFS was 62.0% for localized MCC. Overall survival significantly differed between localized (71.3%) and metastatic (18.5%) disease.
• Adjuvant treatments did not significantly affect recurrence rates (P > 0.05). Platinum/etoposide was a common first-line chemotherapy for metastatic MCC.

Conclusions:

• While rare, MCC incidence is rising in Turkey.
• Factors like gender, CK20 status, tumor size, lymph node involvement, and adjuvant treatment were not associated with recurrence.
• Early diagnosis and treatment of localized MCC are critical for improved survival outcomes.