Faculty Bibliography

Amelanotic melanoma can have a varied appearance both clinically and microscopically. Here, we present our experiences with 75 cases of amelanotic melanoma defined clinically as a non-pigmented lesion and histopathologically as a tumor lacking significant melanization. We evaluated microscopic features such as morphology, mitotic count, nuclear atypia and presence of solar elastosis. Our amelanotic melanomas exhibited the following morphology: epitheloid (72%), spindled (18.7%) or desmoplastic (5.3%). In addition, we obtained patient information and clinical presentations on most of the cases (74/75; 98.7%) and follow-up data on 40% (30/75) of the cases. The majority of amelanotic melanomas in men were found on the trunk (13/45; 29%), head and neck (12/45; 26.7%), and lower limb (13/45; 29%) and in women were found on the lower limb (12/30; 40%), upper limb (10/30; 33.3%) and head and neck (6/30; 20%). In addition, we found that an increase in mitotic index correlated with worse survival (p < 0.026), whereas there were no differences in survival for other pathological features, such as nuclear atypia or solar elastosis. Furthermore, in cases with available tissue, all amelanotic melanoma expressed microphthalmia-associated transcription factor and tyrosinase, suggesting that the tumor cells retained melanocytic lineage and an enzyme in melanin formation, respectively. As the occurrence of amelanotic melanoma and the expression melanoma markers were similar to pigmented melanoma, we favor that amelanotic melanoma represents a subtype of melanoma rather than poorly differentiated or de-differentiated melanoma. Cheung WL, Patel RR, Leonard A, Firoz B, Meehan SA. Amelanotic melanoma: a detailed morphologic analysis with clinicopathologic correlation of 75 cases

A 15-year-old boy with a diagnosis of generalized multiple glomangiomas was referred for evaluation and treatment of enlarging and increasingly painful lesions on his right ankle. The patient underwent a series of two treatments with long-pulsed KTP 1064 nm laser that resulted in substantial improvement in appearance and decreased pain. Generalized glomuvenous malformations, or multiple glomangiomas, are the less common presentation of proliferation of glomus cells and may have extracutaneous involvement. Whereas surgical management is often employed and definitive for solitary lesions, interventions such as laser therapy, may be beneficial for improvement of functional impairment and cosmesis as was observed in our patient.

The presence of lupus erythematosus with morphea in the same patient has rarely been reported. In this case, we describe a woman with the overlap of discoid lupus erythematosus with superficial morphea, diagnoses that are supported by histopathologic features and laboratory studies.

We report the case of a 63-year-old obese man with a rapid-onset of widespread acanthosis nigricans (AN) in the setting of having recently initiated treatment with niacin for dyslipidemia. Although obesity and insulin-resistance are risk factors for AN, AN associated with endocrine dysfunction tends to have a more gradual onset and limited involvement. Owing to our patient's age, the rapid onset, and extensive distribution of his eruption, we initially were concerned about paraneoplastic AN. However, an evaluation for a malignant condition was negative. The timing of the onset of our patient's eruption within several months of starting niacin therapy is consistent with niacin-induced AN. Niacin is known to cause rapidly progressive, widespread AN that is reversible upon discontinuation of the medication. We discuss the pathogenesis of AN, which is thought to be the final common manifestation of stimulation of different subtypes of tyrosine kinase receptors by various epidermal growth factors.

A 58-year-old man presented for evaluation and treatment of non-tender, non-pruritic, annular patches on the right temple and frontal aspect of the scalp that reddened with exercise. A biopsy specimen showed a purpuric dermatitis with features of lymphocytic vasculitis; a diagnosis of exercise-induced progressive pigmentary purpura was made. Whereas progressive pigmentary purpura is purported to be caused by exercise, other similar appearing entities are associated with exercise, namely exercise-induced vasculitis (EIV). EIV may be considered as an acute microcirculatory deficiency and thermoregulation decompensation that occurs after episodes of exhaustive major muscular activity or after unusual or excessive exercise. The combination of age greater than 50 years, heat, and prolonged exercise are the most potent contributing factors. This is the first report of exercise-induced progressive pigmentary purpura.

A 36-year-old man with a prior diagnosis of primary cutaneous marginal-zone B cell lymphoma presented with newly-developed, small, erythematous papules and nodules on his upper left arm and pink-to-skin-colored, clustered papules on his left forearm. A biopsy specimen and immunohistochemical analysis of the left arm lesions showed a lymphocytic infiltrate which stained positively for CD20 and Bcl-2 and negatively for CD10. A PET-CT scan was negative for any extra-cutaneous manifestations of disease. These clinicopathologic findings are indicative of recurrent localized primary cutaneous marginal-zone B cell lymphoma.

Acquired brachial cutaneous dyschromatosis (ABCD) is a newly described disorder of pigmentary change that occurs on the dorsal aspects of the forearms in post-menopausal women. We report a case of a 62-year-old woman who developed an asymptomatic, reticulated, gray-brown eruption on the dorsal aspects of the forearms of gradual onset that is clinically and histopathologically consistent with ABCD. Whereas the original report found an association between hypertension and/or the use of anti-hypertensive medications in the original cohort, we propose that this entity may, in fact, be associated more closely with cumulative sun damage and may be related to such acquired disorders of the skin as poikiloderma of Civatte. Treatment of these lesions may prove to be a challenge, with an emphasis on rigorous sun protection and adjunctive measures with depigmentating agents, chemical peels, and lasers.

A 49-year-old man with advanced HIV/AIDS on anti-retroviral therapy (HAART) and trimethoprim-sulfamethoxazole (TMP-SMX) presented with a several-month history of pruritic, erythematous, lichenified papules that coalesced into hyperkeratotic plaques on the trunk and extremities in a sun-exposed distribution. He shortly thereafter developed a progressive depigmentation over more than 80 percent of his body surface area. A biopsy specimen of an erythematous plaque on the trunk showed a superficial and mid-dermal infiltrate of lymphocytes with eosinophils, most consistent with either chronic lichenoid drug eruption or atypical lymphoproliferative disorder (ACLD) of HIV. The patient's lichenoid skin disease has persisted despite discontinuation of TMP-SMX, although it has improved partially with administration of topical glucocorticoids and acitretin. His depigmentation has continued to progress. We discuss the overlapping diagnostic entities which may be comprised by this patient's clinical disease, and highlight a unique presentation of the complex interaction between HIV infection and the skin.

Erythema ab igne is a reticulated, erythematous or hyperpigmented dermatosis that results from chronic and repeated exposure to low levels of infrared radiation. Multiple heat sources have been reported to cause this condition, which include heated reclining chairs, heating pads, hot water bottles, car heaters, electric space heaters, and, more recently, laptop computers. Treatment consists of withdrawing the inciting heat source. Although erythema ab igne carries a good prognosis, it is not necessarily a self-limited diagnosis as patients are at long-term risk of developing subsequent cutaneous malignant conditions, which include squamous cell and merkel-cell carcinomas.

There are numerous acquired disorders of elastic tissue that are distinguished by a combination of clinical appearance, location, gender, age of onset, and characteristic histopathologic findings. We present a case of a 36-year-old man with multiple confluent, hypopigmented papules that coalesced into plaques with prominent follicular ostia over the dorsal aspects of the forearms, shoulders, upper chest, and upper back. Histologically there was selective loss of papillary dermal elastic fibers. The clinical and histopathologic findings in this case are consistent with an acquired disorder of elastic tissue which we believe represents the second reported case of papillary dermal elastosis.