Primary Cutaneous Follicle Center Lymphoma (PCFCL) with Parotid Gland Involvement

Abstract

Introduction/Objective Primary cutaneous follicle center lymphoma (PCFCL) is the most common primary cutaneous B-cell lymphoma. It arises from mature germinal center B lymphocytes. Here we report two cases of PCFCL with parotid gland involvement. Methods First case is a 66-year-old male with an enlarging forehead mass for nine months and a painless nodule on the right pre-auricular skin. Second is a 39-year-old male with a history of a recurring scalp spindle cell B-cell lymphoma now presenting with an enlarging lesion on the scalp and “fullness” in the right neck. There was no nodal or other extranodal involvement found in either case. Skin and parotid gland biopsies were obtained in both cases. Results Case one: The skin and parotid gland demonstrated sheets of predominantly medium sized infiltrating lymphoma cells, positive for CD20, Bcl-6, CD5 (dim) and Bcl-2 (dim), and negative for CD10, Bcl-1, and MUM-1. The epidermis was spared. Case two demonstrated medium sized, spindle shaped lymphoma cells. The skin showed a vague follicular growth pattern, sparing the epidermis. The parotid gland showed diffuse infiltration by lymphoma cells, positive for CD20 and Bcl-6, Bcl-2 (dim) and no definite positivity for CD10. Fluorescent in situ hybridization for t(14;18) translocation was absent in both cases. Conclusion Dissemination of PCFCL to extracutaneous sites is uncommon (~10% of cases) and to our knowledge, has not been reported in the parotid gland. Here we present two unique cases, which in the absence of nodal disease, prove the diagnosis of PCFCL with parotid gland involvement.