A new papule and “age spots”

Diagnosis: Basal cell carcinoma

Histology confirmed that all 4 lesions were basal cell carcinomas, the most common type of skin malignancy. The temple lesion in Figures 2A AND 3A and the forehead lesion in Figures 2B AND 3B were histologically both pigmented nodular basal cell carcinomas, clinically characterized as pearly papules with pigment. (FIGURE 3A) also demonstrates telangiectasia.

Differential diagnosis: Innocent papule or carcinoma?

The lip lesion, the presenting “symptom,” did not have evident bleeding and crusting on visual or dermoscopic examination. In the absence of a complete history, it could have been “passed off” as an innocent papule, such as a molluscum (though not common in the elderly) or a milial or epidermoid cyst.

Remember that basal cell carcinoma can be subtle. These lesions were missed by a patient and her family—which included a physician within the household—and grew slowly enough that the patient felt they were simply “age spots.” We have seen basal cell carcinomas that patients have indicated have not changed in years—have not bled, ulcerated, or crusted, while symptomatic lesions have been the least impressive, clinically, at the time of the exam. Always maintain a high index of suspicion.

The clinical types of basal cell carcinoma and their dermoscopic findings are summarized in the (TABLE).

TABLE
Clinical types of basal cell carcinoma and dermoscopic findings

CLINICAL TYPE	DERMOSCOPIC FINDINGS	NOTES
Nodular (including noduloulcerative and cystic) “Wart” on a supraclavicular area—note pearly translucency of nodular basal cell carcinoma.	Arborizing (tree-like branching telangiectasias) Dermoscopy of lesion at left, clearly showing arborized telangiectatic vessels.	Most common type Small lesions easily missed Can be difficult to differentiate from irritated seborrheic keratosis, sebaceous hyperplasia, and numerous other papular lesions If pigmented, look for findings of pigmented basal cell carcinoma
Pigmented	Blue-gray ovoid structures (sometimes called “blebs” or “blobs”) (55/97*) Arborizing telangiectasias (52/77*) Multiple blue-gray globules (smaller than ovoid structures and larger than “dots”) (27/87*) Leaf-like or maple leaf–like areas (17/100*) Spoke-wheel structures (10/100*)	Contain melanin in all or part of lesion Dermoscopy may identify highly suggestive features to aid diagnosis May mimic melanoma
Sclerosing, cicatricial, or morpheaform	Arborizing telangiectasias	May appear innocuous Subclinical extension may be extensive; requires Mohs micrographic surgery or wide surgical excision
Superficial	Arborizing telangiectasias	Least aggressive type May resemble eczematoid diseases (eczema, psoriasis, extramammary Paget’s disease, Bowen’s disease)
*Sensitivity/specificity. Sensitivity is the percentage of basal cell carcinomas that possess the feature. Specificity listed is the percentage of melanomas that lack the feature.1 All discussion of dermoscopic diagnosis of basal cell carcinoma assumes absence of a melanocytic pigment network, the presence of which suggests a melanocytic lesion such as a nevus, lentigo, or melanoma.
Note: The primary use of dermoscopy is the evaluation of pigmented lesions. Thus, except to aid in visualization of telangiectasias and ulceration, there are no characteristic dermoscopic findings in other types of basal cell carcinoma. Telangiectasias may not be visualized if the dermatoscope is applied with sufficient pressure to blanch them. Basal cell carcinomas may exhibit no definite or suggestive findings by dermoscopy, as was the case with the lip papule on this patient.