To identify criteria for the diagnosis of squamous cell carcinoma (SCC) and actinic keratosis (AK) by in vivo reflectance confocal microscopy (RCM). Design: Prospective RCM imaging of lesions suspected clinically and/or dermoscopically to be SCC or AK, followed by RCM assessment of the biopsy-proven SCCs and AKs.

A blue nevus of the preorbicularis eyelid skin is extremely rare, and still more uncommon is such a lesion of the eyelid margin. Careful microscopic and immunohistochemical evaluation is necessary to establish the proper diagnosis. Wide local excision should be performed due to concern about a more common and serious melanomatous nodule. A differential diagnosis of other pigmented lesions in this location is offered.

An 86-year-old woman slowly developed a solitary 0.3 3 0.2-cm papule on the left lower eyelid. Complete excision disclosed a honeycombed lesion composed of interlacing basaloid strands unattached to the epidermis but rather extending into the dermis from a dilated hair follicle. The diagnosis was a solitary basaloid follicular hamartoma that can also occur in multiple, generalized, and inherited forms, sometimes with an associated systemic disease. The lesion exhibited a distinctive CD34-positive, mildly cellular myxoid stroma with many CK20-positive Merkel cells scattered within the basaloid cellular strands, which exhibited BCL-2 positivity only within the outermost cells bordering the stroma. These immunohistochemical features are the opposite of those displayed by basal cell carcinomas, which require more aggressive surgical management. Besides basal cell carcinomas, the differential diagnosis of basaloid follicular hamartoma includes fibrofolliculoma, tumor of the follicular infundibulum, poroma, and trabecular (Merkel cell) carcinoma.

No abstract

The authors have indicated no significant interest with commercial supporters.A 58-year-old white man of Irish descent with a medical history of 16 primary melanomas, several basal cell carcinomas (BCCs), and several squamous cell carcinomas (SCCs) presented for a periodic 3-month skin check. The patient's skin cancers began appearing at 21 years of age and most of his melanomas were in situ. The patient had no family history of melanoma, but he reported two blistering sunburns as a child and significant sun exposure during military service and residence in Florida. The melanoma with the worst prognosis was on the eyelid with a Breslow depth of 1.1 cm (Clark Level V) in January 2007. Sentinel lymph node biopsies have been negative and his recent positron emission tomography scan showed three areas of increased fluorine-18 fluorodeoxyglucose uptake indicating either residual tumor or postexcisional inflammation. The patient reported new pink lesions.A thorough examination was performed of all suspicious and nonsuspicious lesions. Clinically, lesion A (Figure 1) on the lateral surface of the left foot was a pink papule with irregular borders. Lesion B (Figure 2) on the left medial leg was a pink macule with a brown crusted plaque at the periphery, and lesion C (Figure 3) on the left upper back was a pink macule with light brown pigment at the inferior border. Clinically and dermoscopically, the differential diagnosis included BCCs, SCCs, and amelanotic/ hypomelanotic melanomas (AHMs).Suspicious dermoscopic findings were seen in each lesion. Lesions A, B, and C (Figures 4-6) all shared similar dermoscopic findings of milky red areas with polymorphous vessels consisting of focal dotted vessels and/or linear irregular vessels of varying shapes and sizes. Both lesion B and lesion C had an irregular brown reticulated pattern at the periphery.Biopsies were performed and the subsequent histopathology examination revealed: lesion A, superficial spreading melanoma with 0.59 mm depth (Clark Level III; Figure 7); lesion B, melanoma in situ arising in a dysplastic nevus ( Figure 8); and lesion C, melanoma in situ with areas of regression ( Figure 9).