Photo Quiz: Do You Recognize These Lesions?

Robert P. Blereau, MD

For 3 years, a 23-year-old man has had this asymptomatic, 0.75-cm, polypoid lesion on his left wrist.

Case 1:

For 3 years, a 23-year-old man has had this asymptomatic, 0.75-cm, polypoid lesion on his left wrist.

What are you looking at here?

Case 1: The lesion was removed by elliptical excision under local anesthesia. Histopathologic examination revealed papillary epidermal change characteristic of hyperkeratosis; fibroepithelial polyp was diagnosed.

Fibroepithelial polyps are acrochordons, or skin tags. These benign lesions have been associated with diabetes mellitus, colon polyps, and acromegaly.

Skin tags occur predominantly on the neck, axillae, groin, and eyelids, as well as beneath pendulous breasts; they are more common in obese women.1 This patient's lesion was on the wrist--an unusual location for a skin tag--and it resembled a cutaneous horn, which may harbor cancer in its base.

Most skin tags can be removed simply by snip excision with local hemostasis (light electrocautery or application of aluminum chloride hexahydrate). Small polyps (less than 2 mm) can be removed by electrocautery alone without local anesthesia. However, for suspicious or uncharacteristic lesions (such as this patient's), a more cautious approach is advisable.

Case 2:

This asymptomatic, brown, conical lesion arose on the left extensor forearm of a 75-year-old man 2 months earlier.

What type of lesion is this, and how is it best removed?

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Case 2: The lesion was completely excised in the office and sent for histopathologic examination.The diagnosis was cutaneous horn with squamous cell carcinoma in situ.

A cutaneous horn--a yellowish brown, indurated, conical excrescence composed of keratin--may be straight or curved and up to several centimeters in length. The lesion develops most commonly on the face, ears, and dorsa of the hands of elderly persons.

Cutaneous horns are associated with many pathologic entities, including actinic keratosis, seborrheic keratosis, inverted follicular keratosis, trichilemmoma, verruca vulgaris, and squamous cell carcinoma.1 They occur rarely with keratoacanthoma, epidermal nevus, epidermal cyst, angiokeratoma, and basal cell carcinoma. The base of the cutaneous horn is more likely to be malignant or premalignant when it is wide; when there is a short height-to-base ratio; and when the lesion develops on the nose, forearms, dorsa of the hands, or a partially to completely bald scalp.

Because of the potential for malignancy, cutaneous horns should be removed and examined pathologically for definitive diagnosis. This can be accomplished by either an elliptical excision with sutured closure or a deep shave biopsy that includes the lesional base and a several-millimeter border.

This patient was advised to check his skin frequently and to seek medical evaluation if any new growths arose.

Case 3:

A 58-year-old man presents with a 1.2-cm, pink, nodular lesion on the right cheek, with prominent telangiectasia around the periphery and ulceration in the center. The lesion had gradually enlarged over several months and had ulcerated about 2 weeks earlier.

What approach would you take?

Case 3: Basal cell carcinoma was initially suspected based on the clinical findings. The patient was referred to a dermatologist who performed an incisional biopsy. Microscopic examination showed that the dermis was filled with nests of dysplastic cells that exhibited abundant cytoplasm, variation in nuclear size and staining intensity, peripheral palisading, and numerous mitotic figures. The dysplastic cells extended to the deep margin of the biopsy specimen. Nodular basal cell carcinoma was diagnosed.

The lesion was treated 3 times by electrodesiccation and curettage. Topical antibiotic ointment was applied until the area had completely healed. The patient will be closely monitored for any evidence of recurrence.

Case 4:

An 81-year-old man has a pink, ulcerated, 1-cm nodule on the right extensor forearm. The lesion has developed rapidly over the past 4 months and is asymptomatic.

What is your clinical impression?

Case 4: The lesion was excised under local anesthesia and examined histopathologically. It was a keratoacanthoma with overlying cutaneous horn, solar elastosis, and chronic inflammation.

Keratoacanthomas are benign epithelial tumors of unknown origin. They usually occur in elderly persons; the annual incidence is 104 per 100,000 adults.1 The lesion arises as a red papule that rapidly enlarges over a few weeks or months and ulcerates. Most keratoacanthomas spontaneously regress within several months; some cause extensive local destruction.

Because sun-exposed surfaces are most commonly affected, skin cancer is prominent in the differential diagnosis. Keratoacanthomas grossly resemble nodular basal cell carcinoma--the difference is that keratoacanthomas develop more rapidly--and they may be difficult to distinguish from squamous cell carcinoma microscopically. Therefore, incisional or excisional biopsy is necessary for diagnosis.

Treatment is usually surgical excision. Shave removal with electrodesiccation and curettage may be used for small lesions. Other treatment modalities include topical 5-fluorouracil, imiquimod, or podophyllum resin; intralesional injections of 5-fluorouracil, methotrexate, or interferon alfa 2a; radiotherapy; and oral isotretinoin.2

Case 5:

An 81-year-old retired offshore boat worker presents for evaluation of an asymptomatic, 3- to 4-mm, round lesion with a partially raised fine border, central crusted ulceration, and diffuse erythema on his forehead. He attributes the lesion to an injury he sustained when a tree branch struck the area 2 years earlier.

The patient has had 3 basal cell carcinomas (1 on the anterior chest, 1 in the left preauricular area, and 1 on the nose) and 3 squamous cell carcinomas (1 on the left temple and 2 on the scalp).

Is this another skin cancer--or something else?

Case 5: Skin cancer was strongly suspected based on the patient's history and the clinical findings. The lesion was removed by elliptical excision under local anesthesia. Based on the histopathologic findings, the diagnosis was superficial basal cell carcinoma (BCC)with solar change and basophilic degeneration of dermal collagen.

An alternative approach would be to perform a small biopsy of the central, and presumably worst, area of the lesion. After superficial BCC is diagnosed, treatment with topical 5-fluorouracil or topical imiquimod could be sufficient.

This patient was advised to monitor his skin frequently and to seek prompt evaluation of any suspicious lesions.