Sex Differences in Overall Survival and the Effect of Radiotherapy in Merkel Cell Carcinoma—A Retrospective Analysis of A Swedish Cohort

Abstract

Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer where Merkel cell Polyomavirus (MCPyV) contributes to the pathogenesis. In an adjuvant setting, radiotherapy (RT) is believed to give a survival benefit. The prognostic impact of sex related to MCPyV-status and adjuvant RT were analyzed in patients referred to Karolinska University Hospital. Data were collected from 113 patients’ hospital records and MCPyV analyses were made in 54 patients (48%). We found a significantly better overall survival (OS) for women compared to men and a significant difference in OS in patients receiving adjuvant RT. Furthermore, we found that men with virus negative MCC have an increased risk for earlier death (HR 3.6). This indicates that MCPyV positive and negative MCC act as two different diseases, and it might be due to different mechanism in the immune response between male and female patients. This could have significance in tailoring treatment and follow-up in MCC patients in the future.

Merkel Cell Carcinoma With Isolated Pancreatic Metastasis

“…8 Clonal integration of the virus may lead to malignant transformation and has prognostic significance. 2,8,10 There is an increased reciprocal risk of MCC with other primary cancers, mainly other skin cancers and certain hematologic malignancies. 11 This may represent shared risk factors such as ultraviolet light and immunosuppression.…”

“… 8 Clonal integration of the virus may lead to malignant transformation and has prognostic significance. 2 , 8 , 10 …”

New Insights into the Biological and Clinical Aspects of Merkel Cell Carcinoma

“…Although limited to Finland, it is presumed that similar situation is a common and worldwide problem, not only with MCC patients, but rather in all patients with rare cancers. Björn Andtback et al [ 9 ] review on their past experience on adjuvant radiation therapy in MCC, strengthening the previous notion that female MCC patients, regardless of MCPyV status, actually do better compared with their male counterparts. The third clinical paper by Naseri et al [ 10 ] summarize the consensus treatment recommendations by the Danish MCC expert group.…”

Diagnosis and treatment of Merkel cell carcinoma: European consensus-based interdisciplinary guideline – Update 2022

“…Several small studies have shown that MCPyV-negative tumours have a worse prognosis and two recent studies showed that MCPyV-positive tumours are associated with a more favourable prognosis. A Swedish study found an increased risk of death for men with a virusnegative MCC (HR 3.6 [64]). A second study showed that MCPyV-positive tumours display longer disease-specific and recurrence-free survival in both univariate and multivariate analysis [74].…”