Faculty Bibliography

We present a case of a 35-year-old woman with a yellow, verrucous, and itchy plaque on her scalp. Within this plaque, there was an erythematous, bleeding papule. Histopathologic findings were compatible with a diagnosis of syringocystadenoma papilliferum within a nevus sebaceous. We present a brief review of the natural history of nevus sebaceus, its pathogenesis, and management.

Pseudoxanthoma elasticum is an incurable, autosomal-recessive, genetic disorder that is caused by mutations in the ABCC6 gene. It is characterized by progressive mineralization and fragmentation of the elastic fibers in the skin, retina, and blood vessels. The characteristic cutaneous features bring the patient to medical attention, but morbidity is related to the degree of extracutaneous involvement. The disease is progressive with phenotypic variability and no definite genotype-phenotype correlation. Treatment is supportive and is directed at prevention and early detection of adverse ocular and cardiovascular sequelae. We present two siblings with pseudoxanthoma elasticum, who have considerable differences in disease related morbidity, which highlights intra-familiar phenotypic heterogeneity

Current treatments of many advanced malignancies, including melanoma, have failed to significantly reduce mortality rates, necessitating newer approaches. There is now abundant evidence that cancer cells, given the appropriate environmental and molecular context, are capable of remarkable plasticity, including complete reversal of the malignant phenotype. Such reprogramming involves both extrinsic and intrinsic factors and can occur via three routes: perturbations of extracellular matrix-cell receptor interactions, modulation of intracellular signaling pathways, and exploitation of epigenetic inheritance. Studies demonstrate the potential for producing dramatic changes in structural, biochemical, immunological, and functional properties of a broad spectrum of tumor cell types, including melanoma, leading to growth arrest, differentiation, senescence, or self destruction. Translating the promise inherent in tumor cell plasticity to the clinical arena remains a major challenge, but it is likely that a variety of epigenetic methods will play an increasingly important and effective role in the future control of malignant melanoma and other cancers

The rare association of severe erosive lichen planus and Castleman's tumor is presented. Castleman's tumor, or giant lymph node hyperplasia, is a benign neoplasm resembling thymic tumors and is associated with several immunologic abnormalities. Lichen planus also is associated with immunologic defects. One hypothesis linking these two diseases is that lymphocytes may become sensitized to tumor antigens on the Castleman's tumor and attack cross-reacting structures in the skin and other stratified squamous mucosae to produce the clinical picture of lichen planus