Elongated and anastomosing rete ridges Atypical basal cells with hyperchromatic-staining nuclei Subtle abnormal maturation (large, eosinophilic keratinocytes) Whorling and keratin pearl formation Usually associated with LS&A Preferential association with HPV-unrelated…
Skin metastases: Nodule, often pigmented, may be ulcerated, multiple or solitary Nodal metastases: Usually in regional lymph nodes Blue nevus-like melanoma: Blue macule/papule, often near original site of primary melanoma…
Most patients have good prognosis, with only minority of cases progressing to systemic disease or death Microscopic • Severely atypical/borderline Spitz tumor Typically, large and deep cellular compound melanocytic tumors May…
Genes implicated include PTCH1 (Gorlin syndrome), TP53, SOX9, BMI1, BAX, RMRP Clinical Issues • Extremely common: Most common cancer in humans • Most common in head and neck region (up to…
Usually presents on scalp in infancy, often at birth Presents as yellowish flat to warty plaque; enlarges during puberty • Basaloid follicular hamartoma Usually presents in adults Microscopic • Nevus sebaceus Abnormalities…
Represent < 0.5% of all oral malignancies • Mean in 6th-7th decades • M > F (2.5-3:1) • Hard palate and maxillary alveolus are most common sites of involvement (~ 80%) • Cervical lymph…
Benign clear cell adnexal proliferation with external root sheath differentiation • Subtype: Desmoplastic tricholemmoma Etiology/Pathogenesis • Some cases are associated with Cowden syndrome (PTEN hamartoma syndrome) Multiple tricholemmomas, hamartomas, and visceral tumors…
Solitary form (myofibroma) Multicentric form (myofibromatosis) • Synonyms: Infantile myofibromatosis, congenital generalized fibromatosis Continuum with lesions termed myopericytoma and infantile hemangiopericytoma Clinical Issues • Most common from birth to 2 years • Most…
Local recurrences Metastases Microscopic • Epithelial islands with interspersed glands/ducts • Cells composing islands are variable Clear Poroid Squamoid (less common) Rarely mucinous • Hyalinized stroma Similar to hidradenoma • Infiltrative growth pattern Not…
Composed of enlarged cells with abundant clear to vacuolated-appearing cytoplasm • Chondroid melanoma Malignant epithelioid cells associated with prominent myxochondroid-appearing matrix • Osteoid melanoma Malignant epithelioid cells associated with prominent osteoid-appearing material…
