Erstine EM, et al. - Considering their recent work regarding Merkel cell carcinoma sentinel lymph node (SLN) metastasis indicating a worse prognosis in correlation to “solid” pattern microscopic metastasis vs the “nonsolid” ones. Researchers compared patients with a nonsolid pattern of SLN metastasis and those with diagnostically negative SLN biopsies (SLNB) regarding their prognostic significance/outcomes. In addition, they evaluated the durability of SLN metastasis after extensive sectioning. In all SLN blocks, they performed five-level, step-wise sectioning at 250-μm intervals with an immunohistochemical stain for CK20 on all levels. They recorded and analyzed the presence and pattern of metastases as they recorded and analyzed corresponding patient and tumor parameters. For all patients (n=38), positive SLNB (n=16) and negative SLNB (n=22) groups, they noted a median follow-up duration of 56.3, 50.4, and 66.8 months, respectively. Nonsolid metastasis had outcome similar to that of negative SLNB with the exception of the sinusoidal pattern, which was associated with worse outcome.