Benign Lid Tumors

Acrochordon

Acrochorda, also called skin tags ( Fig. 27.1 ), are common benign eyelid tumors. Clinically, they appear as small, multiple, flesh-colored lesions attached to the eyelid margin or skin by a thin pedicle. Occasionally they may be large and pedunculated. These tumors are often ambiguously referred to as papillomata, a descriptive yet nondiagnostic term used to describe many cutaneous lesions with various histopathologic diagnoses. A common variant is verruca vulgaris, which is an infectious lesion.

Histopathologically, acrochorda are characterized by thickening of the squamous cell layer (acanthosis) and the keratin layer (hyperkeratosis) without loss of polarity or cellular atypia.

Treatment consists of simple surgical excision of the lesion with a sample of the base included. This is easily performed with scissors or scalpel. Hemostasis is easily achieved with handheld cautery or gentle pressure. Sutured closure is usually not necessary.

Epidermal Inclusion Cyst

This lesion (sebaceous cyst, epidermoid cyst) arises from the infundibulum of the hair follicle. It may occur spontaneously or as a sequela of surgical or traumatic implantation of epidermal tissue into the dermis. Multiple facial inclusion cysts may be seen in patients with Gardner syndrome, an autosomal dominant disorder characterized by intestinal polyps; multiple facial bone osteomas; fibromas and epithelial inclusion cysts of the skin; fibromatosis (dermoid tumors) of the abdominal wall, mesentery, and breasts; and multiple lesions consistent with congenital hypertrophy of the retinal pigment epithelium (CHRPE). Mutations have been demonstrated in the APC gene in patients affected by this disease. ^, This slow-growing, elevated, round, smooth, firm, keratin-filled lesion rarely exceeds 1 cm in diameter ( Fig. 27.2 ). It is often attached to the overlying, thinned skin by the remaining pilar duct, which may appear as a pore. Rupture of the cyst may cause a foreign body reaction, with the cyst becoming secondarily infected. Malignant degeneration is extremely rare.

Recommended treatment is marsupialization or, if possible, complete excision of the cyst without violation of the cyst wall.

Seborrheic Keratosis

Seborrheic keratoses are commonly acquired eyelid lesions affecting middle-aged and elderly patients. Clinical appearance varies considerably in terms of size and degree of pigmentation. This variability makes differentiation from nevi, pigmented basal cell carcinomas, and melanoma difficult in some cases ( Fig. 27.3 ). Single or multiple lesions may be present, and hyperpigmentation is common. The lesions have a different appearance when present on the eyelids versus elsewhere on the face. Facial lesions appear smooth and greasy, with elevated well-demarcated borders producing a classic “stuck on” appearance. Eyelid lesions appear lobulated, papillary, or pedunculated, with friable cerebriform excrescences on the surface ( Fig. 27.4A ). A sudden eruption of multiple seborrheic keratoses may be a cutaneous manifestation of internal malignant disease (Leser-Trélat sign). A heavily pigmented variant with multiple lesions seen in black individuals has been termed dermatosis papulosa nigra.

Seborrheic keratoses are divided into three major types according to the predominant histologic features: hyperkeratotic, acanthotic, and adenoid. Variable degrees of hyperkeratosis and acanthosis are observed in all three. The acanthotic epidermis often contains keratin-filled cystic inclusions. These are referred to as “horn cysts” when they form within the mass and “pseudo–horn cysts” when they represent invaginations of surface keratin. Melanin may be abundant in keratinocytes, especially in the adenoid and acanthotic forms. The dermis is uninvolved except in irritated seborrheic keratoses, in which case it is infiltrated by chronic inflammatory cells.

Surgical excision involves shaving the lesions from the skin surface with a scalpel ( Fig. 27.4B ). Although some lesions are large, the growth pattern is superficial and deep excision is unnecessary. The residual flat surface reepithelializes rapidly.

Milia

Milia are small, raised, round, white, sharply circumscribed cystic lesions of the eyelids. Usually asymptomatic, milia may arise spontaneously, following trauma, in areas of previous radiation, or appear during the healing phase of a bullous disease process. They are particularly common in newborn infants. Histopathologically, these lesions are superficial keratin cysts.

Treatment consists of incision of the overlying skin with a sharp blade or needle and expression of the contents.

Keratoacanthoma

Previously, keratoacanthoma was considered a benign self-limiting lesion. Many authors now regard the tumor as a low-grade squamous cell carcinoma. Although trauma and sunlight exposure have been implicated in its pathogenesis, the exact etiology remains unknown. Immunosuppressed patients also exhibit increased risk. Middle-aged or elderly patients are typically affected. Although commonly solitary, cases involving multiple lesions have been described. Their distinctive clinical appearance and behavior aid in diagnosis. The lesion usually begins as a small flesh-colored papule on the lower lid that develops rapidly over the course of a few weeks into a dome-shaped nodule with a central keratin-filled crater and elevated, rolled margins ( Fig. 27.5 ). Clinically, the lesion often resembles a nodular ulcerative basal cell carcinoma. Gradual resolution over the course of approximately 3–6 months ensues, and visible sequelae are rare.

Muir-Torre syndrome is an autosomal dominant disorder in which individuals have a predisposition toward keratoacanthoma, benign and malignant sebaceous tumors, and visceral malignancies. The syndrome is part of the Lynch cancer family syndrome II, which is associated with mutations in the MSH2 and MLH1 genes.

Ferguson-Smith syndrome (multiple self-healing squamous epitheliomas) is an autosomal dominant condition in which multiple keratoacanthomas are observed. Linkage to 9q31 has been demonstrated.

Histologically, a keratoacanthoma typically has a cup-shaped nodular elevation with thickening of the epidermis. The epidermis contains islands of well-differentiated squamous epithelium surrounding a central mass of keratin. Microabscesses may be present within the islands of squamous epithelium. The dermis shows a polymorphous inflammatory infiltrate.

Although keratoacanthomas are usually self-limited, the prolonged healing period and potential delay in treatment of a possible misdiagnosed malignancy are reasons to pursue a more definitive treatment strategy.

After incisional biopsy confirms the diagnosis, complete surgical excision is the recommended treatment. Large, aggressive lesions have been treated with radiotherapy. Alternative treatment modalities include cryotherapy, intralesional methotrexate, and topical or intralesional 5-fluorouracil.

Pseudo-epitheliomatous (pseudo-carcinomatous) hyperplasia is a condition often seen in areas of cryosurgery or surgical wounds. It is commonly associated with chronic inflammation and shows an active proliferation of epidermoid or squamous cells that develop into a hyperkeratotic nodule on the skin surface. Keratoacanthoma is considered to be a variant of pseudo-epitheliomatous hyperplasia.

Inverted Follicular Keratosis

The clinical presentation of inverted follicular keratosis may vary. Nodular, papillomatous, verrucous, and cystic forms occur. The lesion is usually solitary, and hyperpigmentation is rare. Although the etiology is unknown, it is generally considered a form of irritated seborrheic keratosis.

The term inverted follicular keratosis describes the histopathologic features of this lesion. Epithelial lobular acanthosis with overlying hyperkeratosis and occasional central keratin-filled, cup-shaped invagination is observed. There is a proliferation of uniform basaloid cells with an abrupt transition to concentrically arranged squamoid cells. The dermis is uninvolved.

Treatment is surgical excision.

Cutaneous Horn

Cutaneous horn is a clinically descriptive nondiagnostic term. This lesion may be associated with a variety of benign or malignant lesions, including seborrheic keratosis, verruca vulgaris, and squamous or basal cell carcinoma.

Treatment should be directed at the underlying cutaneous lesion. Biopsy of the base of the cutaneous horn is required to establish a definitive diagnosis. Simple excision of the horn itself provides insufficient tissue for accurate diagnosis.

Linear Epidermal Nevus

A linear epidermal nevus may be solitary and localized or multiple and part of the systemic epidermal nevus syndrome. The lesion consists of multiple closely set, papillomatous, hyperkeratotic papules. Lesion color varies with the degree of pigmentation and hyperkeratosis. Individuals affected with the epidermal nevus syndrome may have associated skeletal deformities and central nervous system CNS disorders.

Surgical excision is usually curative. Alternate therapeutic modalities include cryotherapy, electrodesiccation, dermabrasion, and topical treatment with retinoic acid.

Nodular Elastosis With Cysts and Comedones (Favre-Racouchot Syndrome)

This condition occurs in the sun-damaged skin of older, fair-skinned Caucasians. Multiple comedones and yellow nodules with central comedones occur most commonly near the lateral canthus and extend to the malar eminence and temple. The eyelid and facial skin often reveal other signs of actinic damage. Actinic comedonal plaque is a variant of this condition, in which a solitary plaque with small nodules, dilated follicles, and numerous underlying comedones occurs on the eyelid and facial skin.

Treatment includes topical retinoic acid and mechanical removal of the cysts and comedones.

Actinic Keratosis (Solar Keratosis)

Damage to the epidermal cells of the skin by ultraviolet radiation may result in actinic or solar keratoses. Fair-skinned older patients with a history of sun exposure of significant duration are typically affected. Lesions are multiple and affect the face, scalp, forearms, and backs of the hands. The lesions have a yellow-brown or erythematous color, an oval shape, and a white scale. They may occur anywhere on the eyelids ( Fig. 27.6 ). Although they may be precursors to squamous cell carcinoma, mitotic activity is low and metastases are rare. Individuals with xeroderma pigmentosum have a predisposition to actinic keratoses and malignancies of the skin. This is an autosomal recessive condition due to a defect in repair of UV light–induced damage to the DNA of epidermal cells. There are at least four different genetic loci.

Histopathology of actinic keratoses shows hyperkeratosis, irregular acanthosis, focal parakeratosis, dyskeratosis, focal atrophy, and atypical keratinocytes.

Treatment modalities include topical liquid nitrogen, electrodesiccation, topical imiquimod, and topical fluorouracil.

Dermoid and Epidermoid Cysts

Dermoid and epidermoid cysts are choristomas that occur as a result of the sequestration of ectoderm along the lines of embryonic closure. They contain dermal and epidermal elements, respectively. Both cyst walls are lined by keratinizing epidermis. Dermoid cyst walls also contain dermal appendages, including sebaceous glands, sweat glands, and hair follicles. Secretions from contained sebaceous and sweat glands fill the cyst and cause a gradual increase in its size. In comparison, epidermoid cysts are filled with keratin.

Although such cysts are present at birth, their clinical presentation may not occur until later in life. The lateral brow and upper lid adjacent to the frontozygomatic suture are the most common locations ( Fig. 27.7 ). Dermoid cysts presenting medially at the nasofrontal suture in the orbit must be differentiated from a meningocele or a meningomyelocele. A large dermoid cyst may compress the globe and cause astigmatic amblyopia. Deprivation amblyopia may be caused by a dermoid-induced mechanical ptosis. Extension into the orbit is not uncommon, and large cysts may extend into the cranial vault. Rupture of the cyst releases irritating secretions, which may cause a severe inflammatory reaction. Rupture should be treated intraoperatively with copious irrigation and postoperatively with corticosteroids.

Histologically, the dermoid cyst wall is lined with a stratified squamous epithelium. The cyst wall typically possesses dermal appendages including sebaceous and eccrine sweat glands that secrete directly into the lumen of the cyst. Hairs contained in the cyst wall project into the cyst lumen.

Recommended treatment is complete surgical excision without rupture of the cyst wall. Indications for surgical resection include clinical evidence of manifest or threatened amblyopia or cosmetic deformity. Radiologic imaging with computed tomography (CT) and magnetic resonance imaging (MRI) is indicated when the entire extent of the cyst cannot be palpated, in the setting of proptosis, or when significant orbital or intracranial extension is suspected. The lesion is nonenhancing and well circumscribed.

Oncocytoma

Oncocytoma is a rare tumor composed of oncocytes or large eosinophilic cells that grow in an adenomatous pattern. Oncocytes are thought to be epithelial cells that undergo transformation with aging. Although the majority of oncocytomas arise from the caruncle, they may also occur at the mucocutaneous border of the eyelid, the lacrimal sac, or the conjunctiva. Rare in patients under the age of 60 years, this benign tumor exhibits slow growth. It rarely exceeds 15 mm in diameter; the color varies from red to yellow, and the surface may be smooth or lobulated. ^,

Treatment is surgical excision.

Phakomatous Choristoma

Phakomatous choristoma is a rare lesion believed to be a congenital neoplasm of lenticular anlage. The anteroinferior aspect of the medial lower eyelid is the predominant location ( Fig. 27.8 ). The cells of origin of this lesion are postulated to be surface ectodermal cells induced to form the lens plate and lens vesicle: these cells aberrantly remain external to the optic vesicle as the embryonic fissure closes. The characteristic inferonasal lower eyelid location corresponds to the site of closure of the embryonic fissure. The ectopic cells then proliferate after undergoing rudimentary differentiation. The globe is usually free of developmental defects.

Treatment is surgical excision.

Tumors Derived From Neural Tissue

Neurofibroma

Neurofibromas (plexiform neurofibroma) may occur as solitary cutaneous lesions or as part of the phakomatosis neurofibromatosis type I (NF-1, von Recklinghausen disease), an autosomal dominant condition in which mutations have been demonstrated in the NF1 gene. Solitary neurofibromas usually occur in adulthood. Multiple cutaneous tumors of neurofibromatosis tend to appear in late childhood or adolescence and gradually increase in size and number. Neurofibromas are soft in consistency, flesh colored, and often pedunculated. Clinical distinction from dermatofibromas and intradermal nevi may be difficult. A plexiform neurofibroma of the upper lid gives a characteristic S-shaped curve to the lid margin and is pathognomonic for NF-1 ( Fig. 27.9 ).

Neurofibromas are tumors resulting from the proliferation of all elements of a peripheral nerve. Histologically, the tumors are poorly circumscribed and composed of spindle-shaped cells embedded in a loose myxoid stroma. This pattern represents a proliferation of Schwann cells and endoneural fibroblasts embedded in collagen. Extension of the tumor outside the perineural sheath is not observed. The tumors may be highly vascularized.

Surgical excision is the recommended treatment when solitary lesions cause mechanical lid distortion (upper lid ptosis or lower lid retraction) leading to visual deprivation or exposure keratitis. Cosmetic deformity and the establishment of a diagnosis are additional indications for excision. The tumors are highly infiltrative; thus complete excision is often not possible without significant sacrifice of adjacent structures. Recurrence is common.

Tumors Derived From Smooth Muscle

Tumors Derived From Vascular Tissue