Skin and Soft-Tissue Lesions

Skin and Soft-Tissue Lesions Benign non-pigmented skin lesions Benign pigmented skin lesions Malignant non-pigmented skin lesions Malignant melanoma Sarcoma

Benign non-pigmented skin lesions • The epidermis • The dermis • Hair follicles • Eccrine glands • Sebaceous glands • Neural tissue. • Cysts • Epidermoid cysts • Pilar cysts • Milia • Xanthalasma.

Skin lesions of epidermal origin Basal cell papillomas Squamous papillomas Viral warts Actinic keratosis

Basal cell papillomas • This common lesion is also known as a seborrheic keratosis. • It is a greasy plaque-like lesion usually found on the torso of elderly patients. • If indicated, treatment is by curettage.

Squamous papillomas • These common skin lesions are also known as ‘skin tags’ and ‘acrochordons’. • Treatment is by excision.

Viral Warts • These lesions are caused by the human papilloma virus. • Treatment is with cryotherapy or curettage.

Actinic keratosis • These are scaly crusted areas that occur in the sun-exposed areas of the elderly. • Approximately 20–25% develop into squamous cell carcinomas (SCCs).

Keratotic horns • This is a hard protruding lump of cornified material. • An actinic keratosis (AK), or occasionally an SCC, is usually found at the base of the lesion.

Bowen’s disease • Red scaly lesion usually found on the legs of elderly patients. • Limited to the epidermis (in situ SCC). • Progress to form invasive SCCs. • Non-operative treatment has produced good results.

Keratoacanthoma Enlarge rapidly to form nodules with a central keratotic core. Typically involute without treatment leaving a depressed scar. Histologically : difficult to differentiate from SCCs.

Skin lesions of dermal origin Lesions derived from the hair follicles Trichoepithelioma Trichofolliculoma Tricholemmoma Pilomatrixoma Lesions derived from the eccrine glands Eccrine poroma Cylindroma Syringoma

Lesions derived from the sebaceous glands Sebaceous hyperplasia Sebaceous adenoma Sebaceous nevus Lesions derived from neural tissue Neurofibroma

Trichoepithelioma • These are translucent pinky–white nodules. • They are often located around the nose and mouth.

Trichofolliculoma Nodules with a central pore which often contains a collection of white hairs. Histologically : Esemble basal cell carcinomas (BCCs). However, unlike BCCs, they contain keratin-filled macrocysts.

Trichilemmoma Well-defined, smooth, asymptomatic papules or verrucoid growths.Small. Differentiation toward cells of the outer root sheath The lesion is often seen in the face and neck region

Pilomatrixoma Known as a calcifying epithelioma of Malherbe. Hard subcutaneous nodule, typically located on the face of children. Treatment is by excision.

Eccrine poroma Present as  asymptomatic, slow-growing, or stable nodular lesions on the palm and the sole.

Cylindroma • These pink lesions usually occur on the scalps of the elderly. • Large or multiple lesions are known as ‘turban tumours’.

Syringoma These small, firm, skin-coloured nodules typically occur on the eyelid and chest.

Sebaceous hyperplasia Small yellowish lesions are usually found on the face Clinically, they can be confused with BCCs Severe sebaceous hyperplasia of the nose is known as a rhinophyma.

Sebaceous adenomas These small smooth papules usually occur on the scalp of the elderly. Gradual onset of small, usually less than 0.5 cm in diameter (2-4 mm), smooth, yellow, sometimes speckled papules with central umbilication

Sebaceous naevi This lesion is also known as a sebaceous naevus of Jadassohn • It is normally present at birth but usually enlarges and becomes raised in puberty due. • These lesions are usually removed as they have a 20–30% chance of malignant transformation.

Sebaceous naevi

Neurofibroma Skin-coloured nodules are composed of neural tissue and keratin.

Neurofibromatosis or von Recklinghausen’s disease • Multiple cutaneous neurofibromas • Five or more café-au-lait patches >1.5 cm in diameter • Axillary freckling • Lisch nodules on the iris (ocular neurofibromatosis). • Neurofibromatosis has been classified into many subtypes. •

Neurofibromatosis • Type 1: the most common type consists of the features listed above • Type 2: associated with neurofibromas within CNS. • Plexiform neurofibromas are large infiltrative lesions usually found in the head or neck region. • Wound complications are common following their excision.