Effects of 1,540-nm Fractional Nonablative Erbium and 2,940-nm Fractional Ablative Erbium on p53 Epidermal Expression After 3 months: A Split-Face Interventional Study.

Background: Expression of p53 by keratinocytes may be important in the pathogenesis of skin cancer induced by ultraviolet light.

Objective: We used side-by-side nonablative and ablative erbium fractional laser resurfacing to assess the effects on expression of p53 by facial keratinocytes.

Methods: Ten female patients (age range, 50-63 years) with Fitzpatrick skin Types I-IV and clinical signs of photoaging underwent erbium fractional laser resurfacing (nonablative, 1,540-nm; ablative, 2,940-nm) on opposite sides of the face.

Comparative study of the different degrees of risk of gastrointestinal stromal tumor.

Objective: To evaluate the applicability of the main categories of risk and morphological factors in the prognosis of gastrointestinal stromal tumors.

Methods: we retrospectively studied fifty-four cases of GIST, assessing the main prognostic factors of this neoplasis: risk levels, topography, size, mitotic index, necrosis, histological subtype and immunophenotype. We also verified their association and the reduction of overall survival.