. Author manuscript; available in PMC: 2022 Sep 3.

Published in final edited form as: Actas Dermosifiliogr. 2009 Dec;100(Suppl 2):49–54. doi: 10.1016/s0001-7310(09)73378-2

Table 2.

Overview of the Consensus Staging System for Merkel cell carcinoma

Stage I: Local, tumor diameter ≤ 2cm
Ia:	Nodes microscopically negative and not clinically detectable
Ib:	Nodes not clinically detectable (no pathologic eval of nodes done)
Stage II: Local, tumor diameter > 2cm
IIa:	Nodes microscopically negative and not clinically detectable
IIb:	Nodes not clinically detectable (no pathologic eval of nodes done)
IIc:	Primary tumor invading bone/muscle/fascia/cartilage
Stage III: Regional Nodal Disease
IIIa:	Micrometastasis
IIIb:	Macrometastasis (clinically detectable)
Stage IV: Distant Metastatic Disease