EPIDERMAL TUMORS. A. BENIGN. 1. SEBORRHEIC KERATOSIS. -It is a benign neoplasm most commonly seen in elderly, having an appearance of a raised, flat, soft, well demarcated brown lesion. -Is located mostly on the trunk, limbs & head. -Micro: proliferation of squamous epithelium + cysts filled with keratin
BENIGN...(cont.) 2. KERATOACANTHOMA. -Are keratotic papules that grow rapidly(3-6 wks.) on skin exposed to sunlight, with characteristic volcano-like lesion(umbilicated) resembling a squamous cell carcinoma. -Frequent spontaneous regression without Tx in 6-12 mo. scar -Micro: endophytic papillary proliferation of keratinocytes with some atypias that may be confused with squamous cell Ca.
BENIGN...(cont.) 3. MULTIPLE KERATOACANTHOMAS. There are some rare conditions in which multiple keratoacanthomas may appear: -Ferguson-Smith familial keratoacanthomas More common in men, with large and some times self-healing lesions. -Grzybowski eruptive keratoacanthomas, with multiple itchy lesions that may appear in the skin and mucosal surfaces that can result w/deformity
BENIGN...(cont.) 4. EPIDERMOID CYST. -Formerly and incorrectly named “sebace ous”(sebaceous gland NOT involved), is lined by stratified squamous epithelium filled with keratin. -It is a typical nodular lesion with a soft-gray material as content
BENIGN...(cont.) 5. ACTINIC KERATOSIS. -Provoked by an excessive and chronic exp osure to sunlight, is considered as “premalignant” -It is typically seen as hyperkeratotic, scaly pla ques on the face, neck, limbs and trunk. -Affects most commonly to old patients -Micro; stratum corneum w/parakeratosis & atypic keratinocytes that may evolve to Ca. in situ invasive squamous cell carcinoma.
BENIGN...(cont.) 6. MELANOCYTIC TUMORS. NEVOCELLULAR NEVUS(MOLE). -Is originated in the deep layers of the skin (nevus cells) and is clearly related to sun ex posure. -There are several types: junctional, compound and intradermal. -Gross: uniform tan/brown color w/sharp delineati on and tendency to be stable in size and shape. -Malignant transformation is uncommon
BENIGN...(cont.) 7. MESENCHYMAL TUMORS. ACHROCORDON(SOFT FIBROMA). -Also known as “cutaneous tags” occur in two types: as multiple filiform, smooth or fu rrowed soft papules, especially on the neck and in the axillae, and as a solitary soft, bag-like, pedunculated growths on the trunk or limbs.
BENIGN...(cont.) MESENCHYMAL... DERMATOFIBROMA. -Occur in the skin as a firm, indolent, single or multiple nodules. Usually the nodules arise in adults, mostly on the limbs. -It may have from few mm. in diameter to 2-3 cm in size. Gross: lesions w/reddish color or reddish-brown because of hyperpigmentation of the over laying skin.
BENIGN...(cont.) MESENCHYMAL... HEMANGIOMAS(Capillary, Cavernous) -Capillary or “strawberry”hemangiomas con sist of one or several bright-red, soft, lobula ted tumors that first appear between 3rd-5th week of life, increase in size for several months and then regress involution.
BENIGN...(cont.) MESENCHYMAL... HEMANGIOMAS... -Cavernous hemangiomas consists of large, predominantly subcutaneous mass that may cause deformity. It can be seen in associa - tion w/ some other congenital conditions: Mafucci syndrome ( dyschondroplasia, fragility of bones + osteochondromas) and Blue Rubber-bleb nevus(large bluish tumors on skin + subcutaneous hemangiomas + intestinal and visceral lesions)
BENIGN...(cont.) NEUROFIBROMAS. -It may occur as solitary cutaneous lesions, in which case one finds no café-au-lait spots and no family history of the disease. -Multiple cutaneous lesions w/café-au-lait spots, dominantly inherited, referred as neurofibromatosis or von Recklinghausen´s disease that starts to be manifested since childhood
B. PREMALIGNANT 1. LENTIGO MALIGNA(HUTCHINSON) -Appears in sun-damaged skin of elderly -It is a large pigmented macule, usually in white patients. 2. DYSPLASTIC NEVI(BK MOLES). -Are lesions that can have >5 mm in diameter and may occur as hundreds of moles in some individuals on both, sun-exposed and non sun-exposed areas of the skin, and have been seen in members of families(heritable melanoma syndrome)
C. MALIGNANT. 1. BOWEN´S DISEASE. -It can be seen in non-sun exposed areas like oral mucosa, vulva, etc. and is frequen tly associated to a visceral malignancy. -Clinically appears like an erythematous plaque with indolent growth. -Micro: a typical Ca. in situ
MALIGNANT ...(cont.) 2. BASAL CELL CARCINOMA. -Is the most common malignant tumor due to sun exposure in patients over 40´s with pale skin. -It appears mainly in the face and can be destructive(erosion of the nose sinuses) but almost never metastasize -Gross: pearly papule, rodent ulcer, superficial ca., scar-like, pigmented lesion -Micro: nests of epith.cells that resemble epidermal basal cells forming palisades + whorls of fibroblasts.
MALIGNANT...(cont.) 3. SQUAMOUS CELL CARCINOMA. -Less common than BCC and often seconda ry to AK, develops in sun-exposed skin of fair patients w/light hair & freckles -It has an increased tendency to metastasize locally -It may also appears in chronic scarring processes (osteomyelitis tracts) more invasive -Clinical: may arise in dorsal surface of hands,face lips, ears w/small lesion initially ulceration later
MALIGNANT...(cont.) 4. MALIGNANT MELANOMA. -Sunlight seems to have an important role in the development of this tumor in the skin: appears most frequently on the upper back (males/women) or on the legs(women). -Also, lightly pigmented individuals have higher risk to get a melanoma than those darkly pigmen ted. In addition, the presence of a pre-existing lesion (dysplastic nevus), hereditary factors or exposure to certain carcinogens melanoma
MALIGNANT...(cont.) MELANOMA... -Superficial malignant melanoma is the MOST common type, but after 1-2 yrs nodular melanoma -Acral(distal) lentiginous melanoma affects mostly fingers and toes(nails) and is the most type in colored patients
MALIGNANT...(cont.) 5. MYCOSIS FUNGOIDES(T-cell lymphoma) -In fact it represents a stage in the wide spec trum of lymphoproliferative disorders that affects the skin. -There are 2 different clinical types: a chronic proliferative disorder and a nodular eruptive presentation. Also, it can be seen a more agressive form of adult T-cell leukemia/lymphoma
KAPOSI SARCOMA. -There are four types of the disease: chronic (European KS), lymphadenopathic(African or endemic KS), transplant-associated (immunosuppresion-associated) and AIDS- associated(most common form in US) present in approximately 1/3 of AIDS patients, particularly male homosexuals. -The morphology of KS is similar in different types, w/relatively indolent evolution in old men as well as in non-AIDS presentation of the disease.