Effect of imiquimod as compared with surgery on the cancerization field in basal cell carcinoma.

BACKGROUND: Patients with basal cell carcinoma (BCC) have an increased risk of subsequent BCCs. It is possible that imiquimod might reduce this risk by acting on the cancerization field. OBJECTIVE: To examine the ability of imiquimod to reduce subsequent BCCs. METHODS: Retrospective cohort study of patients with BCC treated at our hospital between 2003 and 2011. The patients were divided into 2 groups depending on whether they had been treated with surgery or with imiquimod. Comparing the 2 groups, we analyzed the development of new BCCs, the time that elapsed between first and subsequent tumors, and the site of occurrence of the second BCC with respect to the first one (local, same lymphatic drainage basin or anatomic region, or other). Survival methods were used to analyze the data. RESULTS: We reviewed the charts of 623 patients. Of these, 550 had been treated with surgery (88.3%) and 71 with imiquimod (11.4%). Overall, a second BCC occurred in 36.4% of patients (n=227). The rate of occurrence was 38.2% in the surgery group and 23.9% in the imiquimod group (P=.02). The hazard ratio for the occurrence of a subsequent BCC was 2.13 (95% CI, 1.28-3.53) for patients treated with surgery compared with those treated with imiquimod. Imiquimod reduced the risk of a second BCC locally, regionally, and in the lymphatic drainage area. Our findings are limited by the retrospective nature of our study and the small number of patients treated with imiquimod. CONCLUSIONS: Imiquimod may reduce the risk of subsequent BCC in patients treated for BCC and its effect could last for up to 2 years in local, regional and lymphatic cancerization fields. We believe that the cancerization field concept should be expanded to include not only the local area, but also the pertinent anatomic region and the regional lymphatic drainage area.

[Effectiveness of primary care physicians and dermatologists in the diagnosis of skin cancer: a comparative study in the same geographic area]. / Estudio comparativo de la habilidad en el diagnóstico clínico del cáncer cutáneo entre el médico de familia y el dermatólogo en una misma área geográfica.

BACKGROUND: skin cancer is the most common malignant tumor in white individuals. Early diagnosis and treatment are key factors in reducing morbidity. We performed a prospective observational study throughout 2008 to assess the ability of primary care physicians to diagnose nonmelanoma skin cancer. METHODS: the study was undertaken in a single geographic area corresponding to the region served by a primary health care center. Patients who were referred to a dermatologist were included if the primary care physician indicated skin cancer in the differential diagnosis on the referral form. Patients were also included if the dermatologist suspected skin cancer even if the referral from primary care had not indicated it. RESULTS: primary care physicians had a sensitivity of 0.45 and a specificity of 0.16 for the diagnosis of skin cancer, whereas dermatologists had a sensitivity of 0.97 and a specificity of 0.75. The α statistic as a measure of agreement was -0.56. CONCLUSIONS: The ability of primary care physicians to diagnose skin cancer was appreciably lower than that of dermatologists. This may result in substantial delays in the provision of appropriate care for patients with skin cancer considering the role played by primary care physicians in screening for the disease in the Spanish national health system.