Fig 1.
Immunohistochemistry of the MCPyV large T-antigen (LTA) shows that the antigen is predominantly expressed in the nuclei of Merkel cell carcinoma cells.
Panel (A) demonstrates no expression of the primary tumor whereas in panel (B) a positive expression of MCPyV LTA can be appreciated. In Panel (C) one can observe no LTA expression compared to positive expression in lymph node metastases (D). All photomicrographs are taken at x100 magnification.
Fig 2.
Five samples, which were negative and 5 samples, which showed positive immunostaining, were used for PCR.
The MLK1 Merkel cell carcinoma cell line was used as positive control for the establishment of the MCPyV PCR (Fig 2).
Table 1.
MCPyV status and clinicopathologic data of 41 patients with Merkel cell carcinoma.
Table 2.
Immunohistochemistry of MCPyV large T-antigen (LTA) and outcome data in 54 specimens from 41 patients with Merkel cell carcinoma.
Fig 3.
Kaplan-Meier survival curves depict disease-free survival of 41 MCC patients according to tumor stage (Fig 3A) and tumor localization (Fig 3B). Patients with higher tumor staging survived significantly shorter (p < 0.001) whereas patients with MCCUP had a better outcome than patients with primary tumors of the head and neck region, the trunk or the extremities (p = 0.268).
Fig 4.
Disease-free survival (DFS) stratified by expression of the MCPyV large T-antigen (LTA) in lymph node metastases.
Patients with LTA-positive (green line) MCC lymph node metastases had a shorter DFS (p = 0.002)(Fig 4A) and OS (p = n.s.)(Fig 4B) than patients with LTA-negative (blue line) lymph nodes. (n.s. = not significant).