Chapter 16: Benign Tumors and Vascular Lesions

For the clinician a clear knowledge of the most common benign tumors and important. Identifying a lesion that falls outside of the spectrum of common benign tumors and requires further evaluation or referral is critical. This fundamental insight will help alleviate the concern of a patient who presents with an otherwise benign lesion. It will also allow the clinician to first screen and differentiate common lesions that may have simple treatments, or no required treatment, from those lesions that are of more concern.

Clinical Presentation

History and Physical Examination

Seborrheic keratoses are present in approximately 50% of adult patients. Many patients present with a history of a changing pigmented "mole" and a concern about melanoma. Patients may complain of pruritus or irritation from clothing. A classic seborrheic keratosis has a predilection for the trunk and presents as a well-defined hyperpigmented papule or plaque with a waxy hyperkeratotic surface, ranging in size from a few millimeters to several centimeters in diameter (Figure 16-1). They are often oval in shape with their long axis following the natural tension lines of the skin. The astute clinician can quickly recognize these lesions and avert the need for a biopsy, but occasionally even with the most trained eye a biopsy is indicated. Variants include the macular seborrheic keratosis of the face and scalp that present as a slightly raised velvety plaque or pigmented macule on the head and neck. These lesions are often misdiagnosed as a lentigo with concern for lentigo maligna melanoma. A facial variant is dermatosis papularis nigra which presents primarily in African Americans with small dark papules (Figure 16-2). Stucco keratosis is another variant and presents as smaller scattered lightly pigmented or white keratotic papules on the distal lower extremities (Figure 16-3).

Laboratory Findings

Histopathology shows that all variants of seborrheic keratosis are limited to thickening of the epidermis with trapping of keratin in elongated tracks called horn pseudocyts. These can be seen under dermoscopy or by careful observation with the unaided eye.

Differential Diagnosis

• ✓ Lentigo: Macule with even hyperpigmentation and a smooth scalloped border, most commonly on sun-exposed areas of face and hands.

• ✓ Nevus: Tan to black macules or papules; surface is not hyperkeratotic or waxy.

• ✓ Melanoma: Hyperpigmented macule/papule with irregular color, border, and shape.

Management

There is no specific treatment that is required other than differentiated seborrheic keratoses from other lesions that would have malignant potential. For irritated or disfiguring lesions, cryotherapy (Chapter 7) can be beneficial. Care must be taken however to not over-treat as a scar can replace the lesion. Patients must be warned that with any treatment persistent hypo- or hyper-pigmentation may occur. Alternative treatments include electrocautery or desiccation with or without curettage.

Indications for Consultation

Lesions that cannot be clearly defined as benign.

Patient Information

American Academy of Dermatology: www.aad.org/skin-conditions/dermatology-a-to-z/seborrheic-keratoses

Clinical Presentation

History and Physical Examination

Lentigines are common benign hyperplasias of melanocytes. They are usually acquired, but occasionally are congenital, especially as part of congenital syndromes such as LEOPARD (Moynahan) syndrome and Peutz–Jeghers syndrome. They commonly begin in the third decade of life and present as light or dark brown macules with sharp borders in sun-exposed skin, primarily dorsal hands (Figure 16-4), forearms, and shoulders. They may also occur on mucous membranes and the nail bed. Lentigo simplex occurs without ultraviolet exposure and can develop as early as the first decade of life. These present as sharply marginated monochromatic light or dark brown macules. Patients rarely bring lentigines to medical attention except in the context of "unsightly" age spots or concern for melanoma.¹

Laboratory Findings

Histopathology shows an increased number of melanocytes in the basal cell layer of the epidermis.

Differential Diagnosis

• ✓ Lentigo maligna: Macular hyperpigmentation, in a similar distribution, but with variations in color and irregular border, typically in older adults.

Management

Lentigines do not have a medical indication for removal. Common cosmetic management techniques include bleaching creams (eg, hydroquinone) and cryotherapy. Prevention is the best approach to solar lentigines with the regular use of sunscreens. The natural history of lentigines is to persist over time and darken with age and sunlight exposure.

Indications for Consultation

Cosmetically bothersome lentigines can be referred for laser and intense pulsed light treatment (monochromatic noncoherent light visible light).

Clinical Presentation

History and Physical Examination

Most patients present with concern over a symptomatic "mole." The classic presentation of a dermatofibroma is a firm 3- to 10-mm papule or nodule on the distal lower extremities that may have an associated increase in pigmentation (Figure 16-5). The etiology of these lesions is not certain, but is thought to be related to a healing process from a minor traumatic event that leads to proliferation of dermal fibroblasts. The pigmentation of these lesions is symmetrical often with a lighter central area and a collaret of darker pigmentation. Horizontal compression, or pinching of the lesion, leads to dimpling due to the deep collagen connection (dimple sign). Dermatofibromas can entrap nerves within the scar leading to sensations of itch or sensitivity.

Laboratory Findings

Histopathology shows a localized area of spindle cell proliferation of fibroblasts in the dermis.

Differential Diagnosis

• ✓ Nevus: Tan to dark, brown, soft macule or papule. Dimple sign is negative.

• ✓ Dermatofibrosarcoma protuberans: Firm nodule similar to a dermatofibroma, but larger in size and has progressive growth with time.

• ✓ Melanoma: Flat or raised lesion with variable pigment and irregular borders.

Management

Treatment options are limited. Intralesional triamcinolone injections and cryotherapy can be used, but may have limited success. Reassurance of the benign nature of the lesions with no treatment is appropriate for asymptomatic lesions. Those lesions with prominent itch or tenderness can be surgically removed with the caveat that the patient is trading the round scar of a dermatofibroma for a linear scar of the excision.

Indications for Consultation

Lesions with continued growth, poorly defined lesions.

Patient Information

British Association of Dermatologists: www.bad.org.uk/site/809/Default.aspx

Clinical Presentation

History and Physical Examination

Skin tags are very common skin-colored papules with a thin stalk (Figure 16-6). The stalk contains a central blood vessel. They most commonly present in patients in their mid-40s to late 60s in sites of friction such as the neck, axillae, and groin. Weight gain correlates with an increased incidence.

Laboratory Findings

Histopathology shows loose fibrous tissue in the dermis of a polyp with a thin epidermis.

Differential Diagnosis

• ✓ Neurotized nevus: Very similar appearance to skin tags, but presents as single lesion.

• ✓ Neurofibroma: May be polypoid, but typically are larger than skin tags, and may present within the context of a genetic syndrome.

Management

Cryotherapy can be useful in treating multiple skin tags, but success is limited to lesions that have a narrow stalk. Broad-based lesions are best treated with thin shave excision. Electrodessication and removal with iris scissors can be used for smaller lesions. Any treatment often leaves behind a small hypopigmented macule.

Indications for Consultation

Numerous lesions.

Patient Information

PubMed Health: www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001851/

Clinical Presentation

History and Physical Examination

Sebaceous hyperplasia presents as a 2- to 4-mm yellow- to skin-colored papule(s) on the central face and forehead (Figure 16-7). They represent a hyperplasia of sebaceous glands. They often have a central depression.

Laboratory Findings

Histopathology shows hyperplasia of sebaceous glands.

Differential Diagnosis

• ✓ Milia: 1- to 2-mm white cyst with no central depression.

• ✓ Basal cell carcinoma: Small basal cell carcinomas, have a similar appearance, but grow continuously.

• ✓ Acne: Transient erythematous inflammatory papules lasting less than 2 months.

Management

Lesions that are progressive or show symptoms of tenderness or bleeding should be biopsied to rule out basal cell carcinoma. Observation is sufficient for stable lesions. Cosmetically bothersome lesions can be treated with shave removal with or without electrodessication. Electrodessication on its own can be used as well for smaller lesions. A small scar is often left after treatment.

Indications for Consultation

Lesions with progressive growth.

Clinical Presentation

History and Physical Examination

A lipoma represents a localized overgrowth of fat cells. A lipoma often presents as a rubbery nodule in areas of potential inadvertent trauma (Figure 16-8). The tendency to form lipomas appears to run in families and a number of syndromes present with multiple lipomas that may number from a few to hundreds. Lipomas come in two main variants, classic and angiolipoma. The angiolipoma variant clinically is similar to the classic lipoma but may have an associated tenderness. These lesions lead to a deep aching sensation with minor pressure or trauma and can be quite distressing to the patient.

Laboratory Findings

Histopathology shows adipose tissue surrounded by a fibrous capsule.

Differential Diagnosis

• ✓ Liposarcoma: Similar presentation to a standard lipoma, but much more aggressive history of growth.

• ✓ Epidermal cyst: Firm cyst with a central puncta.

• ✓ Neurofibroma: Can present as exophytic skin-colored papules or more rarely, as in this differential, a plexiform subcutaneous mass with a firm consistency.

Management

Options for management include observation or surgical removal.² During surgical excision of a lipoma, the cells that make up the lipoma can often be identified as a cluster of "grape like", slightly more firm or rubbery fat cells. Classic lipomas have a tendency to have a deeper yellow color than surrounding normal fat cells.

Indications for Consultation

Symptomatic or large lesions may be referred for surgical removal.

Clinical Presentation

History and Physical Examination

The terms keloid and hypertrophic scar are often used synonymously. However there is a key difference in these two entities that has major clinical implications. A hypertrophic scar arises in a site of injury and is limited by the borders of the original injury (Figure 16-9). It may be symptomatic and increase in firmness with time but will not extend beyond the border of the original injury. A keloid scar is not limited by the borders of the original injury and will extend well beyond the wound to form a fibrous mass that greatly exceeds the initial injury region. The threshold for injury that leads to keloid scarring appears to be much lower than that for hypertrophic scarring as well.

Laboratory Findings

Histopathology is similar for keloids and hypertrophic scars. A keloid shows whorls of fibroblasts in the dermis. Histopathology of a keloid may show thicker bands of collagen in the dermis.

Differential Diagnosis

• ✓ Sclerotic basal cell carcinoma: Very similar appearance, but with progressive growth.

• ✓ Dermatofibrosarcoma protuberans: Firm tan nodule with progressive growth.

• ✓ Foreign body granuloma: Reactive process at site of injury or previous surgery. Firm nodule with red to brown hyperpigmentation.

Management

Hypertrophic scars will usually improve with time. It may take years, but most scars will become flatter and less firm, however, their overall dimensions will not change. This process can be expedited with the use of intralesional triamcinolone injections.³ It may take multiple sessions spaced 1 to 2 months apart to achieve the desired reduction, and alleviate symptoms of itch or tenderness. Keloid scars can also be treated in a similar manner but may have a more limited response and are much more likely to reoccur once therapy has been discontinued. Surgical correction of hypertrophic scars is often successful. However any attempt at surgical correction of keloid scarring should be approached with extreme caution. It is often the case that the surgical excision only leads to more extensive damage and larger keloid formation.

Indications for Consultation

Lesions that fail to respond to intralesional steroid therapy may improve with laser therapy.⁴

Patient Information

PubMed Health: www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001852/

Clinical Presentation

History and Physical Examination

Epidermal (epidermoid) cyst, also sometimes called sebaceous cyst (a misnomer as they have no relationship to sebaceous glands), can occur in almost any area of the body, but are most common on the central trunk and face. They present as a firm skin-colored cyst with a central punctum. These cysts arise from the infundibulum of the hair follicle. These cells form a layer that is very analogous to that of the epidermis. The cells that form the cyst lining are constantly being sloughed into the center of the cyst and undergo degradation leading to soft keratin with a necrotic center. There is often a rudimentary connection to the epidermal surface that presents as an indentation overlying the center of the cyst (Figure 16-10). This connection can be patent and at times may lead to extrusion of cyst contents. A strong odor is usually associated with this soft "cheesy" material. Patients will often complain of "infection" of a cyst, which most likely represents rupture of the cyst contents into the dermis. The keratin content and cellular debris lead to a robust inflammatory reaction with swelling and tenderness as its hallmark.

Laboratory Findings

Histopathology shows a cyst in the dermis lined with squamous epithelium and filled with keratin.

Differential Diagnosis

• ✓ Pilar cyst: Similar to epidermal cyst, but with no central punctum.

• ✓ Boil or acne cyst: More acute and inflammatory.

Management

Postrupture inflammatory reaction can lead to resolution in a limited number of cases. However, the cyst is more likely to recur. Surgical removal is the standard of care, and should be performed when the cyst is not inflamed and is well formed.⁵ Removal of the entire lining of the cyst is critical to minimize the risk for recurrence.

Indications for Consultation

Need for more complex surgical removal, multiple lesions.

Patient Information

PubMed Health: www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001845/

Clinical Presentation

History and Physical Examination

Pilar cysts are relatively common, presenting in approximately 10% of the population as firm nodules that are generally limited to the scalp. They arise from cells in the hair follicle. As with epidermal cysts, the lining of the cyst is the critical component to the cyst formation. Cells lining the cyst continue to produce keratin, but without connection to a hair. Thus the compact laminate keratin forms a hard sphere within the dermis. The patient may relate a family history of these lesions.

Laboratory Findings

Similar to epidermal cysts, but with no granular layer in the epidermis.

Differential Diagnosis

• ✓ Epidermal cyst: Very similar, but with no central punctum.

Management

Smaller lesions can be observed as they may not grow. Simple removal of the keratin center will not alleviate further formation or recurrence. As in epidermal cysts, complete removal of the cyst lining is required for successful cure.

Indications for Consultation

Tender enlarging lesions requiring surgical removal.

Clinical Presentation

History and Physical Examination

These small 1- to 2-mm white papules which are commonly found around the eyes and on the upper face (Figure 16-11) and represent a smaller variant of epidermal cyst.⁶ They have similar pathology to epidermal cysts; however, milia are more likely to stay small and less likely to be recurrent after removal. They are more common in infants and will often resolve spontaneously. In adults, they are more likely to be persistent or recurrent.

Laboratory Findings

Histopathology shows the same findings as an epidermal cyst, but the diameter of the cyst is smaller.

Differential Diagnosis

• ✓ Closed comedones: More common in teenagers and adults with acne.

• ✓ Syringoma: Skin-colored to clear papules, 1 to 3 mm in diameter primarily present on the lower eyelids.

• ✓ Trichoepithelioma: Multiple skin-colored papules that typically occur in the area of the medial canthus, but may extend onto the eyelids and dorsal nose.

Management

Observation is often best, but the cyst's contents can be extracted by simple thin incision overlying the lesion with a #11 blade. Care should be taken not to go deeper than the keratin contents, less than 1 mm in depth. Careful removal of the cyst wall may be possible through the incision once the keratin contents have been extracted. Care should be taken not to cause undue trauma which will lead to scar formation.

Indications for Consultation

Multiple lesions, enlarging or recurrent lesion for surgical removal.

Patient Information

PubMed Health: ncbi.nlm.nih.gov/pubmedhealth/PMH0002343/

Clinical Presentation

History and Physical Examination

Digital mucous cysts are pseudocysts, because they do not have a cellular lining. They represent an extrusion of contents from a local joint space into the surrounding dermis. They may have a lining that mimics a cell-based lining of a true cyst, but this only represents a compression of cells within the dermis to the margin of the extruded contents. They most commonly present as a translucent skin-colored cyst on the distal aspect of a digit of the hand either overlying the proximal matrix of the nail or underlying the nail bed (Figure 16-12). They may cause distortion of nail formation due to pressure exerted on the matrix of the nail.⁷ As the nail plate grows distally it maintains the shape of the distended matrix.

Laboratory Findings

Histopathology shows a focal area of mucin in the dermis.

Differential Diagnosis

• ✓ Glomus tumor: Rare benign bluish, neoplasm, usually solitary, around or often under the fingernail plate. It is one of the painful tumors of the skin.

• ✓ Osteoma: Solid, non-compressible nodule that most often develops in a site of previous trauma.

Management

These lesions will often resolve after rupture of the cyst, but may recur. Extrusion of cyst contents can alleviate pressure on the matrix and pain.⁷ Treatment of the sinus tract with cautery or ligation leads to a greater rate of success with less recurrence.

Indications for Consultation

Multiple lesions, recurrent lesions for surgical excision.

Patient Information

British Association of Dermatologists: www.bad.org.uk/site/1248/default.aspx

Clinical Presentation

History and Physical Examination

These 3 vascular lesions are given names according to the site of presentation and extension above the surface. (1) Cherry angiomas which present as small bright red papules on the trunk are the most common (Figure 16-13). They have a strong family tendency with presentation in the late 30s and increase in number through the 40s and 50s. (2) A venous lake is a deeper lesion localized to the lower lip. These lesions represent dilation of the venules of the lip. Due to the depth of these lesions they are often misdiagnosed as a pigmented lesion, with the patient presenting with a concern for melanoma. (3) Spider angiomas are small macular lesions on the face that present with a central feeder vessel and peripheral dilated vessels (Figure 24-12). These lesions will blanch with pressure, which can be readily observed with pressure under a glass slide.

Laboratory Findings

Histopathology shows dilated capillaries in the dermis.

Differential Diagnosis

• ✓ Traumatic blister: Transient, resolves within days to weeks.

• ✓ Melanocytic lesion: A dark purple cherry angioma or venous lake may appear to be black and mimic nevi. However their underlying color is revealed when pressed with a glass slide or with the use of dermoscopy.

Management

Once diagnosed, no treatment is required. However some lesions will be treated either due to inadvertent trauma leading to bleeding or for cosmetic purposes. Pulsed dye laser (PDL) therapy can lead to resolution of most lesions. Larger lesions on the trunk respond better to shave removal with cautery of the underlying vessels. For lesions of the central face, PDL therapy or fine needle cautery of central feeder vessel will lead to resolution.

Indications for Consultation

Lesions in frictional sites that sustain trauma leading to tenderness or bleeding. Cosmetic treatment.

Patient Information

Cherry angioma; PubMed Health: www.nlm.nih.gov/pubmedhealth/PMH0002413/

Clinical Presentation

History and Physical Examination

Most often a pyogenic granuloma presents as a quickly growing sessile red to purple exophytic papule that bleeds with minimal trauma (Figure 16-14). The term pyogenic granuloma is a misnomer since the growth does not represent a granuloma and it is not related to infection. The lesions tend to evolve in presentation from a small erythematous papule to an exophytic nodule up to 2 cm in diameter over a few weeks. They are most common on the head, neck, and extremities. A subset also present in the oral mucosa. Lesions typically occur in young adults and with pregnancy.

Laboratory Findings

Histopathology shows proliferation of capillaries in the dermis.

Differential Diagnosis

• ✓ Infantile hemangioma: Table 16-1.

• ✓ Squamous cell carcinoma: May present as a similar growth in older adults, but is not usually exophytic.

• ✓ Other: metastatic carcinoma of the skin.

• ✓ Glomus tumor.

Treatment

Surgical excision is indicated as these lesions have a high tendency for bleeding that is difficult to control. Shave removal with cautery of the base may be sufficient. Deeper excision may be required for recurrent lesions.

Indications for Consultation

Surgical excision, recurrent lesions.

Patient Information

PubMed Health: www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002435/

In general vascular lesions present with a violaceous to purple color, but dark purple hues can also be sen and mistaken for melanin pigment. Lesions may present at birth or develop soon thereafter, or may be acquired later in life. Differentiating between these tumors can be difficult even for the experienced clinician.

Clinical Presentation

History and Physical Examination

A vascular malformation is the most common vascular lesion of infancy and is present in greater than one-third of infants. The most common presentation is a focal area of macular erythema on the posterior neck or mid-forehead (stork bite or angle kiss) that fades within the first year of life, but can still be evident with physical exertion including crying.

A congenital capillary malformation is more persistent and forms a nevus flammeus (port-wine stain). These lesions enlarge over many years rather than months and do not have a natural involution phase. These lesions often start with an erythematous patch (Figure 16-15), or slightly raised plaque that evolves to become more exophytic and forms vascular blebs over time. There are a number of syndromes that are associated with port-wine stains such as Sturge–Weber syndrome which presents with a port-wine stain in the trigeminal nerve distribution and may be accompanied by seizures or glaucoma. Larger vascular malformations on the extremities are associated with Klippel–Trenaunay and Parkes Weber syndromes.⁸

Laboratory Findings

Histopathology shows dilated capillaries in the dermis with no proliferation of endothelial cells. Vascular malformations can be subdivided into capillary, venous, arterial or lymphatic or combinations of these structures.

Differential Diagnosis

• ✓ See Table 16-1.

Treatment

The skin manifestations of a port-wine stain can be treated with pulse dye light therapy. Multiple sessions are required as the laser can only penetrate to a limited depth. Early treatment is advised by some clinicians. Recurrence is common, but may respond to additional treatments in a similar manner.

Indications for Consultation

Large lesions with potential for underlying hamartomatous growth and lesions on the face.

Patient Information

Vascular Birthmarks Foundation: www.birthmark.org/node/23

Clinical Presentation

History and Physical Examination

Approximately 2% of live births will have a form of hemangioma. This increases to approximately 10% by 1 year of age. There is an up to 3-fold risk for female infants.⁹ Infantile hemangiomas are not usually present at birth, but early signs of their development such as pallor, or telangiectatic macules may be present in up to 50% of infants who go on to have an infantile hemangioma. At its peak size an infantile hemangioma typically presents as nodule which typically is 1 to 8 cm, but may range from pinpoint size to greater than 25 cm in diameter (Figure 16-16). The natural history for infantile hemangiomas is a period of growth followed by a drawn out involution phase. The growth phase is usually complete by 1 year of age. The involution phase is variable and can last between 2 and 10 years or greater. As the tumor resolves it develops a white-grey area and may ulcerate.

Laboratory Findings

An infantile hemangioma is a vascular tumor, as it demonstrates cellular hyperplasia. While biopsy is not indicated, these lesions can be differentiated from congenital hemangiomas by positive staining for transporter-1 (GLUT-1). Histopathology shows proliferation of endothelial cells in the dermis and/or subcutaneous region.

Differential Diagnosis

• ✓ Vascular malformation (Table 16-1).

• ✓ Lipoma—see above.

• ✓ Pyogenic granuloma—see below.

Management

In the past, patient observation was the rule. However, particular attention needs to be paid to lesions involving cosmetically sensitive areas or areas that my cause disruption of normal development or anatomy. These sites include the nasal tip, periorbital region, ears, lips, genitalia, airway, or beard distribution.¹⁰ Also treatment is recommended for ulcerating lesions. Historically, treatment when indicated was limited to topical or oral steroids with the adjuvant use of pulsed dye laser (PDL) therapy.¹¹ Recently it has been discovered that these lesions respond remarkably well to oral administration of propranolol.¹² This should only be attempted by a very experienced clinician in a controlled setting as this treatment can lead to hypoglycemia¹³ and bradycardia. PDL therapy is still indicated in ulcerative lesions or thin cosmetic lesions.

Indications for Consultation

Lesions in cosmetic or structurally sensitive areas of the nasal tip, lips, visual field, or beard region. Lesions in the groin have a higher incidence of ulceration and pain that warrants referral.

Patient Information

Vascular Birthmarks Foundation: www.birthmark.org/node/24

Clinical Presentation

History and Physical Examination

These uncommon vascular lesions are fully formed at birth. These lesions are designated as rapidly involuting congenital hemangiomas (RICH) or noninvoluting congenital hemangiomas (NICH) depending on their subsequent history.¹⁴ RICH are present at birth and undergo rapid involution early in life, often completed by 12 to 14 months. They may leave behind atrophy of the dermis and subcutaneous tissue. NICH are also referred to as nonprogressive hemangiomas. In contrast to RICH, these lesions do not undergo involution. These two entities generally are difficult to differentiate at birth. NICH often show a peripheral rim of pallor with more prominent surface telangiectasia when compared to RICH.

Laboratory Findings

Histopathology shows proliferation of endothelial cells in the dermis and/or subcutaneous region.

Differential Diagnosis

• ✓ See Table 16-1.

Management

Cautious observation for the first 18 months. Surgical removal may be indicated for NICH at about age 6.

Indications for Consultation

Evaluation of structural or cosmetically sensitive sites. Surgical treatment.