Dermoscopy in family medicine: A primer.

Dermoscopy allows you to see deeper into the skin than with the naked eye. Here's how you can make use of it to spot malignant conditions sooner.

Nodular cutaneous amyloidosis.

A 56-year-old white man presented with a lesion on the right shoulder. The lesion developed during a short period and recently became irritated with occasional bleeding and mild pruritus. The patient denied pain. Medical history included melanoma, nonmelanoma skin cancer, diabetes mellitus type II, hyperlipidemia, multinodular thyroid goiter, and obesity. Medications and family and social history were noncontributory. Review of systems was negative. Examination revealed a slightly raised, friable yellow-pink waxy plaque located on the right shoulder (Figure 1). There was no evidence of excoriation, secondary infection, drainage, scale, crust, atrophy, lichenification, or telangiectasia. The patient had no mucosal or nail changes and the remainder of his skin examination was normal. A shave biopsy on the right shoulder revealed a nodular deposit of homogenous eosinophilic material associated with extravasated erythrocytes within the dermis. An infiltrate of lymphocytes and plasma cells was associated with the deposits. Immunohistochemical stains revealed positive plasma cells with kappa light chain and negative with lambda light chain. Congo red stain was positive and supported the diagnosis. The findings were consistent with nodular cutaneous amyloidosis (NCA) of the amyloid light-type. Initial work-up included referrals to hematology/oncology and to general surgery. The patient had a complete blood cell count (CBC), complete metabolic profile (CMP), serum protein electrophoresis (S-PEP), urine protein electrophoresis (U-PEP), 24-hour urine creatinine clearance, and protein, serum immunoglobulins and 132 microglobulin. These were all within normal limits. Abdominal/pelvic computed tomography and positron emission tomography scan also were within normal limits. Bone marrow biopsy showed no abnormalities. The patient underwent both an abdominal fat pad biopsy as well as a colonoscopy with rectal biopsy. Both were negative for amyloidosis. Initially, the patient's cutaneous amyloidosis remained localized and mild pruritus was controlled with low potency topical steroids. The patient was closely monitored by hematology/oncology and general surgery on a biannual basis to assess the possibility of progression to systemic amyloidosis. Over the course of the subsequent two years, the patient developed multiple similar lesions across the back, shoulders, and chest, which were biopsied and found to be consistent with NCA. Progression of the cutaneous nodules led to disfiguring, painful, and friable pink to yellow waxy papules coalescing into plaques with obvious hemorrhage diffusely over the trunk (Figure 2). In lieu of the painful and disfiguring progression of disease, the patient desired a more aggressive treatment plan. At present, the treatment option recommended to the patient is carbon dioxide laser ablation. Hematology/oncology recommendation consists of a general systemic amyloid reevaluation annually, including CBC, CMP, S-PEP, U-PEP, 24-hour urine collection with creatinine clearance, and history and physical examination.

A requirement for NF-protocadherin and TAF1/Set in cell adhesion and neural tube formation.

Neurulation in vertebrates is an intricate process requiring extensive alterations in cell contacts and cellular morphologies as the cells in the neural ectoderm shape and form the neural folds and neural tube. Despite these complex interactions, little is known concerning the molecules that mediate cell adhesion within the embryonic neural plate and neural folds. Here, we demonstrate the requirement for NF-protocadherin (NFPC) and its cytosolic partner TAF1/Set for proper neurulation in Xenopus. Both NFPC and TAF1 function in cell-cell adhesion in the neural ectoderm, and disruptions in either NFPC or TAF1 result in a failure of the neural tube to close. This neural tube defect can be attributed to a lack of proper organization of the cells in the dorsal neural folds, manifested by a loss in the columnar epithelial morphology and apical localization of F-actin. However, the epidermal ectoderm is still able to migrate and cover the open neural tube, indicating that the fusions of the neural tube and epidermis are separate events. These studies demonstrate that NFPC and TAF1 function to maintain proper cell-cell interactions within the neural folds and suggest that NFPC and TAF1 participate in novel adhesive mechanisms that contribute to the final events of vertebrate neurulation.