Rhabdomyosarcoma Key Points Rhabdomyosarcoma (RMS) is an aggressive tumor that develops from mesenchymal cells of uncertain origin It can occur in any anatomic location of the body where there is…

Primary Cutaneous Mucinous Carcinoma Key Points Sweat gland tumors comprise a large variety of rare lesions that mostly include eccrine carcinomas and less commonly apocrine and mixed eccrine/apocrine tumors Primary…

Plasmacytoma Key Points Plasma cell tumors are derived from a terminally differentiated cell in the B-lymphocyte lineage They originate in the bone marrow during the maturation process from B-blasts to…

Mucoepidermoid Carcinoma Key Points Mucoepidermoid carcinoma (MEC) is a highly malignant epithelial neoplasm comprising mucus-secreting, proliferating squamous, and nondescript intermediate epidermoid cells Although the pathophysiology is unclear, a novel translocation…

Microcystic Adnexal Carcinoma Key Points Microcystic adnexal carcinoma (MAC) is a slow-growing, locally aggressive cutaneous adnexal malignancy derived from eccrine sweat glands It occurs predominantly on the head and neck…

Metastatic Tumors to the Eyelids Key Points Eyelid metastasis is very rare accounting for less than 1% of malignant eyelid lesions Breast carcinoma is most frequent, followed by skin melanoma,…

Merkel Cell Carcinoma Key Points Merkel cell carcinoma (MCC) is a rare, aggressive, cutaneous neuroendocrine malignancy The majority of MCC tumors occur on the face and head, but only 5%…

Malignant Melanoma Key Points Cutaneous malignant melanoma is an invasive tumor of malignant melanocytes On the eyelid, malignant melanoma accounts for about 1% of all eyelid malignancies On the eyelids,…

Lymphoma Key Points Lymphoma is a malignant neoplasm originating from clonal proliferations of monoclonal B cell, T cell, and natural killer cell lymphocytes The ocular adnexa is involved in 2%…

Liposarcoma Key Points Liposarcoma (LPS) is the most common soft tissue sarcoma in adults In the periorbital region, liposarcomas may present in the orbit or on the eyelid They originate…