Differentiating Merkel cell carcinoma of lymph nodes without a detectable primary skin tumor from other metastatic neuroendocrine carcinomas: the ELECTHIP criteria

-Merkel cell carcinoma may initially present in lymph nodes without an evident primary skin tumor.-When this occurs the tumor may be misdiagnosed as lymph node metastasis from other neuroendocrine carcinomas. -The ELECTHIP criteria assists in differentiating between these diagnoses and may help classify patients with neuroendocrine lymph node metastasis.