Undifferentiated Pleomorphic Sarcoma (Malignant Fibrous Histiocytoma) Key Points Undifferentiated pleomorphic sarcoma (UPS) describes a soft tissue tumor of primitive mesenchymal origin that involves deep skeletal muscle, fascia, and adipose tissue…
Trichilemmal Carcinoma Key Points Trichilemmal carcinoma (TC) derives from the outer hair root sheath The pathogenesis of TC is not completely understood, but risk factors include UV and ionizing radiation,…
Squamous Cell Carcinoma Key Points Squamous cell carcinoma (SCC) is a malignant tumor of the squamous layer of cells of the epidermis, showing keratinocyte differentiation It is the second most…
Sebaceous Carcinoma Key Points Sebaceous carcinoma (SbC) is a rare malignant and potentially lethal tumor derived from the adnexal epithelium of sebaceous glands It represents 0.05% of all cutaneous malignancies…
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,…
