To our knowledge, this is the first case of metastatic carcinoid tumor reported that has mimicked a poroid neoplasm.

Pagetoid reticulosis is an indolent primary cutaneous T-cell lymphoma. It typically presents as a solitary and slowly growing patch or plaque on the extremity, histologically characterized by an acanthotic epidermis infiltrated with atypical lymphocytes. Here, we present histological, immunophenotypical and molecular findings of a 29-year-old Jamaican man with bilateral wrist plaques. Histology showed marked acanthosis, hyperkeratosis and an intraepidermal infiltration consisting of large atypical lymphocytes. Immunohistochemical stains showed CD3 and CD5 positive T cells with significant loss of CD7, double negative CD4 and CD8 and strong positive CD30. Molecular analysis showed a monoclonal T-cell receptor (TCR) gamma gene rearrangement. Review of the literature confirms that the immunophenotype of pagetoid reticulosis is variable with decreasing frequency of CD8+ cytotoxic/suppressor T cell, CD4+ helper T cell and least commonly CD4/CD8 double negative phenotypes. Although CD4/CD8 double negative phenotype appears to be associated with higher proliferation index, it does not appear to confer prognostic significance.

Cutaneous metastasis from cholangiocarcinoma is an extremely rare event. Herein, we present three cases with review of the literature. Case 1 is that of a young female with scalp metastasis. Cases 2 and 3 involve cutaneous metastasis to the sites of prior biliary drains, one occurring in a young female with a history of multiple biliary surgeries and one in a male with a history of sclerosing cholangitis. Review of the literature shows that the presentation of cutaneous metastases from cholangiocarcinoma can vary in terms of anatomic location and clinical features. The pathological and immunohistochemical profile of metastatic cholangiocarcinoma can be non-specific, and accurate diagnosis relies in part on clinical correlation. In summary, metastatic disease should always be included in the differential diagnosis of cutaneous lesions in patients with known malignancy.