TTF1 and Merkel cell skin cancer: That two (7%) of our 28 Merkel cell carcinomas showed a moderate TTF-1 positivity is consistent with the sum of earlier data describing TTF-1 positivity in 0% of 12 [56], 0% of 20 [31], 8% of 52 [57], 11% of 103 [58], and 80% of 5 [32] Merkel cell carcinomas.