The skin is one of the organs most frequently affected by extranodal lymphomas. Cutaneous lymphomas are peculiar in many aspects. (1) In contrast to nodal lymphomas, cutaneous T-cell lymphomas are more frequent than B-cell lymphomas. (2) Cutaneous T-cell lymphomas develop in a multistep process, exhibiting distinct clinical, histologic, and molecular-biologic features. They progress very slowly over a period of years or decades. (3) The disease becomes manifest very early on. (4) The skin provides a unique structural and humoral (cytokines) microenvironment to attract T cells and B cells to home to under distinct promotional conditions. (5) Treatment strategies for cutaneous lymphomas are quite different from those for nodal lymphomas.
Cutaneous squamous cell carcinoma (SCC) is the second most common skin cancer in whites. Despite the fact that these tumors are largely preventable, the incidence of SCC is rising every year, and shows no signs of abating. While ultraviolet radiation is the most common cause of this type of cancer, other factors including ionizing radiation, human papillomavirus, chemical agents, immunosuppression, and chronically injured or inflamed skin also predispose to SCC development. Invasive SCC may arise from a precursor lesion such as actinic keratosis, or from SCC in situ, and may exhibit a wide spectrum of clinical features. Similarly, the histopathology of SCC may be-viewed as a spectrum of squamous intraepithelial neoplasia, within which a variety of common and more unusual variants have been identified. Since invasive SCC has the potential to recur and metastasize, it is important to recognize those factors placing individual lesions at a higher risk for recurrence or metastasis. These include size > 2 cm, location on the ear, lip, and other specific sites on the head and neck, as well as acral and genital regions, degree of histologic differentiation, perineural invasion, immunosuppression, and history of previous treatment. Treatment of primary cutaneous SCC is essential both to mitigate locally destructive growth and to minimize the risk of metastatic spread. While low risk lesions may be treated effectively with electrodesiccation and curettage, excision, cryosurgery, radiation therapy, or photodynamic therapy, high risk SCCs may require Mobs micrographic surgery or excision with wider margins to minimize their risk of recurrence. Adjunctive treatment with radiotherapy, lymph node dissection, systemic chemotherapy or biologic response modifiers may be required for the treatment of regional or distant metastatic disease. Screening via total body skin examination is the only test available to detect cutaneous SCC. Patients at risk for developing SCC should be identified early, and patients with a previous history of skin cancer should be monitored for the development of new and recurrent skin lesions. The role of prevention through sun avoidance and protection from sunlight, beginning in childhood, cannot be underestimated. Physicians should emphasize to their patients that these prophylactic measures will help to minimize their risk of developing this potentially life-threatening cancer, and that prompt detection of early disease will maximize their chance of complete treatment with a high rate of cure.
Since the 1970s, long distance communication technology has become highly developed. Along with the communications revolution has been a parallel in the use of the technology to deliver health care. Early work in rural Western states, Canada, and Europe laid the groundwork for the rapid expansion of telemedicine programs throughout the world in the 1990s. Dermatology has played an important role in many programs because of the visual nature of the field. Pilot programs in both interactive video and store-and-forward have demonstrated effectiveness in diagnosing cutaneous disease and skin tumors. Equally important to the delivery of teledermatologic care is the ability of dermatologists to make management recommendations beyond the training of most primary care physicians. Telemedicine technology is continuing to advance with improvements in cameras, lenses, and monitors and increased access to higher-end communications options such as integrated services digital network and digital subscriber lines. Further advances over the next decade in both hardware and software will likely further enhance the ability to diagnose cutaneous disease at a distance. As with any clinical practice, understanding the legal ramifications is very important before entering into a field. Licensure issues continue to be a barrier for teleconsultations across state lines. Consent for teleconsultations, credentialing where applicable, and liability and liability insurance issues are very important to address before starting a teleconsultation service. The technology of telemedicine, although decreasing in cost, still has a high price tag. To date there are few good data to justify teleconsultations on a cost savings basis. Intangible factors such as distance traveled for a live consultation and time away from work become important in the overall cost-effectiveness analysis but have little direct financial benefit for a practicing physician. Improvements in technology and increased accessibility often mean lower costs, which may eventually favor teleconsultations. Despite the cost and difficulties associated with teledermatology, it still presents itself as a very viable form of health care for rural or underserved populations and may serve to reach communities where dermatologists are not readily available. (Curr Probl Dermatol 2002;14:1-40.)
Cosmetic procedures are becoming increasingly popular with dermatologists. They are used to reverse the effects of aging, to improve the quality of the skin, to augment facial structures, and to improve the patient's appearance in general. They can also be beneficial for certain dermatoses. We present an introduction to cosmetic dermatologic procedures, focusing on chemical peels, botulinum toxin injections, and the use of filler substances. Following this review, the reader should have the basic knowledge to consider training to perform such procedures safely and effectively, even if he or she has not done so previously. Several agents are available for chemical peeling, each with unique properties for different therapeutic effects. Superficial peels penetrate the epidermis only and include α-hydroxy acids, salicylic acid, low-strength trichloracetic acid (TCA), and Jessner's solution. These epidermal peels are used to treat mild photoaging and other epidermal dermatoses such as acne vulgaris and are generally performed with the use of a series of peels. Medium-depth peels, such as medium-strength TCA or combination peels that use a superficial and medium-depth agent, extend into the papillary dermis or upper reticular dermis. They can eradicate fine lines and wrinkles, improve color variation, eliminate some actinic keratoses, and correct textural irregularities. Higher-strength TCA and phenol induce deep wounding into the mid-to-deep reticular dermis. These deep peels can be used to help eradicate heavy wrinkles and lines due to chronic photodamage, but their use has largely been replaced by erbium and CO laser resurfacing. Histologic studies have shown that peeling agents help alter the structure and content of the skin, increase production of collagen and glycosaminoglycans, eliminate solar elastosis, and normalize epidermal atypia. Complications are largely related to infection, pigmentary alteration, delayed healing, and scarring, but appropriate patient screening and prophylaxis can minimize their incidence. Botulinum toxin injections are used in dermatology for two main purposes: elimination or attenuation of dynamic lines and wrinkles on the face and neck and elimination or attenuation of sweating in the case of hyperhidrosis of the hands, axillae, and/or feet. With an excellent safety profile and proven efficacy, these are popular procedures for patients. The medication is a neurotoxin that works by temporarily inhibiting the release of acetylcholine. The administering physician must be familiar with pertinent anatomy with respect to muscles of facial expression, appropriate doses, and injection sites, all of which are covered herein. In addition to being an effective treatment by itself, botulinum toxin injections can be combined with other procedures such as laser resurfacing, filler substance injections, facelifts, blepharoplasty, etc, to prolong and improve the results. Filler substances are injected in or below the skin in order to replace lost volume or to increase existing volume. They are frequently used for the nasolabial folds, lips, and perioral area, but they can also be used more extensively, as is the case in pan-facial structural lipoaugmentation. Fillers are occasionally used in nonfacial areas as well, such as in aging dorsal hands or other areas of atrophy. A number of filler substances are available. The main classes of fillers are bovine collagen, human collagen, polysaccharide fillers, fat, synthetic fillers, and combination filler substances. Most filler substances are temporary in their effect, but some do persist in the skin forever. The treating physician must be familiar with proper selection, handling, location and depth of placement, longevity, costs, benefits, and risks of each substance that he or she uses. The necessary information is covered in this text. This text is intended to be a complete introduction to the above-mentioned cosmetic dermatology procedures. It includes aspects such as history and mechanism of action, but it really focuses on the clinical information necessary to be able to consider performing these procedures. It includes suppliers of products, precise descriptions of how to carry out the procedures, and clinical pearls to help achieve successful outcomes. Curr Probl Dermatol 2003;15:35-83.
Cutaneous drug eruptions are among the most common adverse reactions to drug therapy, the etiology of which reflects immunologic and/or nonimmunologic mechanisms, the former encompassing all of the classic immune mechanisms of Gell and Combs. The latter reflect cumulative and synergistic effects of drugs including interactions of pharmacokinetic and pharmacodynamic factors such as the alteration by one agent of the effective serum concentration of another and the molecular interactions of drugs and their metabolites. It has recently been observed that concurrent infection with lymphotropic viruses may enhance drug effects by promoting lymphoid blast transformation and lymphocyte survival. Drug reactions may also be dramatically affected by intercurrent systemic connective tissue disease syndromes that promote enhanced lymphocyte longevity and the acquisition of progressively broadening autoantibody specificities, a phenomenon that is also of import in drug-induced lupus erythematosus. To confirm the relationship between drug intake and the provocation of a cutaneous eruption in any given patient, ideally one should establish that (1) the onset of the eruption correlates temporally with drug ingestion, resolves with discontinuation of the suspect agent, and recurs following rechallenge; (2) the suspect drug is established to provoke the adverse effect seen in the patient; and (3) an alternate explanation is unlikely. (Curr Probl Dermatol 2002;14:117-146)
Vascular birthmarks are a relatively common problem seen frequently by dermatologists. Although interventional measures were not available for many years, the development of new strategies such as embolization, laser therapy, and α-interferon injections has altered our approach to these disorders. Because we now have the means to provide effective treatment for some of these lesions, it is important to distinguish proliferative but self-limited lesions from morphogenetic errors that are permanent defects. This monograph provides an overview of pediatric vascular lesions using the nomenclature devised by Dr. John Mulliken. In this schema, vascular birthmarks are classified as either hemangiomas, tumors with both a growth and an involutional phase, or vascular malformations, permanent structural anomalies composed of capillaries, veins, arteries, or lymphatic vessels. Also reviewed are several syndromes that have vascular lesions as a cardinal feature. An attempt has been made to properly classify the vascular component of these disorders, as some vascular malformations have erroneously been labeled hemangiomas in the existing literature. These errors have caused considerable confusion and sometimes inappropriate management. Unfortunately, space constraints permit discussion of only those vascular malformation syndromes that are associated with structural anomalies of the capillaries (vascular stains). Finally, the various therapeutic modalities available for these patients are reviewed.
The term encompasses a number of genetic skin disorders linked by the common finding of abnormal epidermal differentiation, often with aberrant formation of the cornified envelope (cornification). These disorders, such as ichthyoses, palmoplantar keratodermas, and erythrokeratodermas, have been classified traditionally on the basis of clinical morphology and the presence or absence of extracutaneous manifestations. In many cases the features do not facilitate easy segregation into a single distinct and well-defined group (eg, palmoplantar keratoderma and ichthyosis coexist in a number of conditions). These inherited disorders of keratinization may also feature epidermal fragility. Clinical, histologic, and ultrastructural morphologic characteristics of these conditions have been used to further classify and subdivide them. As none of these diseases is common, the morphologic approach has great benefit to the practicing clinician and offers a logical pathway to diagnosis when confronted with a patient for the first time in the clinic. Advances in genetic technology during the past 10 years have led to an enormous increase in understanding the basic molecular defects responsible for inherited disorders of keratinization, and these advances have made possible a new, molecular mechanism-based approach to their classification that complements the morphologic system. In the great majority of cases recent molecular insights have confirmed the accuracy of the original clinical distinctions and stand as testimony to the skilled and detailed observations made by generations of clinicians. As knowledge increases, however, the association of mutations in one gene with a distinct phenotype has become more complex. For example, clinically distinct conditions have been attributed to different mutations in the gene (clinical heterogeneity). A further example of clinical heterogeneity is the spectrum of phenotypes attributable to mutations in the gene that encodes desmoplakin 1; dominantly acting mutations cause a skin-limited phenotype, but recessively acting mutations may cause a dilated cardiomyopathy and hair phenotype in addition to epidermal changes. In others, identical clinical phenotypes have been attributed to mutations in several genes (genetic heterogeneity), for example, with lamellar ichthyosis, in which 4 gene loci in addition to that encoding transglutaminase 1 have been identified. A sound knowledge of these issues is vital to the clinician involved in the care of patients with inherited disorders of keratinization. The direct benefits to patients of this increased knowledge are improved diagnostic certainty, an understanding of the biology underlying the gene defect, and more accurate genetic counseling. It is likely that this increased understanding will lead to the development of more rational treatments for many of these distressing conditions in the near future. Attempts at gene therapy have been limited to date, but ex vivo gene correction has succeeded for both lamellar ichthyosis and recessive X-linked ichthyosis in mouse models. (Curr Probl Dermatol 2002;14:71-116)