High-risk nonmelanoma skin cancers

Sarcomas cutâneos primários

Os sarcomas com apresentação cutânea primária são tumores raros e de grande heterogeneidade histológica. Com a evolução da oncologia cutânea e da cirurgia dermatológica, os dermatologistas têm sido cada vez mais requisitados para o diagnóstico e orientação terapêutica de tumores menos freqüentes. Este artigo de revisão analisa os sarcomas cutâneos primários observando suas características clínicas, etiopatogênicas e histológicas, bem como aspectos do tratamento e evolução. Enfatiza os sarcomas de maior relevância para o dermatologista, como angiossarcoma, dermatofibrossarcoma protuberans, fibroxantoma atípico, leiomiossarcoma, lipossarcoma, tumor maligno de bainha de nervo periférico e sarcoma epitelióide. O sarcoma de Kaposi não é abordado devido a suas características individuais específicas.

Skin cancer screening and prevention in the primary care setting: national ambulatory medical care survey 1997

OBJECTIVE

To describe skin cancer prevention and screening activities in the primary care setting and to compare these findings to other cancer screening and prevention activities.

DESIGN

Descriptive study.

SETTING/PATIENTS

National Ambulatory Medical Care Survey 1997 data on office-based physician visits to family practitioners and internists.

MEASUREMENTS AND MAIN RESULTS

Data were obtained on 784 primary care visits to 109 family practitioners and 61 internists. We observed that the frequency of skin cancer prevention and screening activities in the primary care setting was much lower than other cancer screening and prevention activities. Skin examination was reported at only 15.8% of all visits (17.4% for family practitioners vs 13.6% for internists, P >.1). For other cancer screening, the frequencies were as follows: breast examination, 30.3%; Papanicolaou test, 25.3%; pelvic examination, 27.6%; and rectal examination, 17.9%. Skin cancer prevention in the form of education and counseling was reported at 2.3% of these visits (2.9% for family practitioners vs 1.5% for internists, P >.1), while education on breast self-examination, diet and nutrition, tobacco use, and exercise was 13.0%, 25.3%, 5.7%, and 17.9%, respectively.

CONCLUSIONS

The results of this study indicate that the proportion of primary care visits in which skin cancer screening and prevention occurs is low. Strategies to increase skin cancer prevention and screening by family practitioners and internists need to be considered.

The state-of-the-art in chemoprevention of skin cancer

The incidence of skin cancer (both melanoma and non-melanoma) continues to grow at an alarming rate. Our chemoprevention strategies include the development of novel agents evaluated by (1) preclinical mechanistic studies in models of ultraviolet (UV) radiation-induced skin carcinogenesis; (2) clinical studies of immunohistochemical surrogate endpoint biomarkers in high-risk patients; and (3) randomised, placebo-controlled phase I, II and III clinical chemoprevention trials. Recent clinical results validate this development model. Molecular targets of chemopreventive strategies for melanoma and non-melanoma skin cancers include the ras and activator protein-1 (AP-1) signal transduction pathways. A transgenic murine melanoma model has been developed for evaluating potential agents in vivo. Agents at various stages of study include the green tea catechin epigallocatechin gallate (EGCG), the limonene derivative perillyl alcohol, the ornithine decarboxylase inhibitor alpha-difluoromethylornithine (DFMO), selenium, retinoids and salicylates. New chemopreventive agents that can be used to complement sunscreens may result in decreased incidence, morbidity and mortality of skin cancer.