Clinicopathological characteristics and prognosis of Merkel cell carcinoma: a single-center retrospective study in Korea.

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine tumor of the skin with high mortality. However, its clinical characteristics in Asian patients remain uncertain owing to its low incidence. To analyze the clinicopathological features of MCC and identify factors associated with its prognosis. The medical records of 62 patients with MCC were retrospectively reviewed. Data on clinical features, survival outcomes, prognostic factors, histopathology and immunohistochemical profile of the patients were collected and analyzed. Merkel cell polyomavirus status was evaluated using immunohistochemistry. The incidence of MCC significantly increased over time. The mean duration of follow-up was 51.2 months, with an overall 5-year survival of 80.6%. More female patients with MCC were identified than male patients (1.3:1). Approximately half of the patients had stage I disease at the time of initial presentation. The primary tumor was frequently located in the lower extremities (40.3%), followed by the head and neck (32.3%), upper extremities (22.6%), and the trunk (4.8%). Male sex was associated with poorer overall survival (p = 0.003). Post-resection adjuvant radiotherapy significantly improved the overall survival (p = 0.023). Sentinel lymph node biopsy during surgery ameliorated the progression-free survival (p = 0.036) in patients with stage I or II cancer. Lymphovascular and perineural invasion were associated with a poor prognosis. Old age, immunohistochemical profiles, and Merkel cell polyomavirus-positivity were not associated with prognosis. Post-surgical adjuvant radiotherapy and sentinel lymph node biopsy significantly improve the course of MCC.

Moon IJ ，Na H ，Cho HS ，Won CH ，Chang SE ，Lee MW ，Lee WJ ... -  《-》

Epidemiological, Clinicopathological and Virological Features of Merkel Cell Carcinomas in Medical Center of University of Pécs, Hungary (2007-2012).

Horváth KB ，Pankovics P ，Kálmán E ，Kádár Z ，Battyáni Z ，Lengyel Z ，Reuter G ... -  《-》

Sentinel lymph node status in Merkel cell carcinoma of the head and neck: not a predictor of survival.

The effect of sentinel lymph node status on survival in patients with Merkel cell carcinoma (MCC) of the head and neck is uncertain. We used the Surveillance Epidemiology and End Results (SEER) database to identify patients with MCC who underwent sentinel lymph node biopsy (SLNB). Clinicopathologic data and disease-specific survival (DSS) were compared among patients with positive and negative sentinel lymph nodes. We identified 721 patients with cutaneous MCC who underwent SLNB, of which 173 (24%) had head and neck MCC. The rate of sentinel lymph node positivity in patients with head and neck MCC was 23.1%. Sentinel lymph node metastasis did not significantly affect survival in head and neck MCC (p = .139). Using the SEER database, we report what we believe to be the largest head and neck MCC study to date. Our results suggest that sentinel lymph node status does not predict survival in head and neck MCC. Independent predictors of MCC-related mortality seem to be unique in the head and neck region.

Fritsch VA ，Camp ER ，Lentsch EJ 《-》

Merkel cell carcinoma: histopathologic and prognostic features according to the immunohistochemical expression of Merkel cell polyomavirus large T antigen correlated with viral load.

Merkel cell carcinoma (MCC) is a neuroendocrine skin malignancy frequently associated with Merkel cell polyomavirus (MCPyV), which is suspected to be oncogenic. In a series of MCC patients, we compared clinical, histopathologic, and prognostic features according to the expression of viral large T antigen (LTA) correlated with viral load. We evaluated the LTA expression by immunohistochemistry using CM2B4 antibody and quantified viral load by real-time polymerase chain reaction. We analyzed formalin-fixed, paraffin-embedded (FFPE) tissue samples (n = 36) and corresponding fresh-frozen biopsies when available (n = 12), of the primary tumor and/or metastasis from 24 patients. MCPyV was detected in 88% and 58% of MCC patients by real-time polymerase chain reaction and immunohistochemistry, respectively. The relevance of viral load measurements was demonstrated by the strong consistency of viral load level between FFPE and corresponding frozen tissues as well as between primary tumor and metastases. From FFPE samples, 2 MCC subgroups were distinguished based on a viral load threshold defined by the positivity of CM2B4 immunostaining. In the LTA-negative subgroup with no or low viral load (nonsignificant), tumor cells showed more anisokaryosis (P = .01), and a solar elastosis around the tumor was more frequently observed (P = .03). LTA-positive MCCs with significant viral load had a lower proliferation index (P = .03) and a longer survival of corresponding patients (P = .008). Depending on MCPyV involvement, 2 MCC subgroups can be distinguished on histopathologic criteria, and the CM2B4 antibody is able to differentiate them reliably. Furthermore, the presence of a significant viral load in tumors is predictive of better prognosis.

Leroux-Kozal V ，Lévêque N ，Brodard V ，Lesage C ，Dudez O ，Makeieff M ，Kanagaratnam L ，Diebold MD ... -  《-》

Sentinel lymph node biopsy in Merkel cell carcinoma: Predictors of sentinel lymph node positivity and association with overall survival.

Merkel cell carcinoma (MCC) is a rare, aggressive malignancy with high rates of recurrence and metastasis. To evaluate predictors of sentinel lymph node (SLN) positivity in MCC using the National Cancer Database. The National Cancer Database, from 2012 to 2014, was used to identify 3048 patients with MCC, of whom 1174 received an SLN biopsy. Predictors of SLN positivity were evaluated using logistic regression. Overall survival was evaluated using a Cox proportional hazards model. Of patients who underwent SLN biopsy, those with primary lesions on the trunk (odds ratio, 1.98; 95% confidence interval [CI], 1.23-3.17; P = .004), tumor-infiltrating lymphocytes (odds ratio, 1.58; 95% CI, 1.01-2.46; P = .04), or lymphovascular invasion (odds ratio, 3.45; 95% CI, 2.51-4.76; P < .001) were more likely to have positive SLNs on multivariate analysis. Overall survival was negatively affected by age ≥75 years (hazard ratio [HR], 2.55; 95% CI, 1.36-4.77; P = .003), male sex (HR, 1.78; 95% CI, 1.09-2.91, P = .022), immunosuppression (HR, 3.51; 95% CI, 1.72-7.13; P = .001), and SLN positivity (HR, 3.15; 95% CI, 1.98-5.04; P < .001). Lack of disease-specific survival and potential selection bias from a retrospective data set. Truncal MCC, tumor-infiltrating lymphocytes, and presence of lymphovascular invasion were independent predictors of positive SLNs. Overall survival was negatively affected by advancing age, male sex, immunosuppression, and SLN positivity.

Conic RRZ ，Ko J ，Saridakis S ，Damiani G ，Funchain P ，Vidimos A ，Gastman BR ... -  《-》