Bcl-2 and CD10 expression in the differential diagnosis of trichoblastoma, basal cell carcinoma, and basal cell carcinoma with follicular differentiation.

BACKGROUND: Both trichoblastoma and basal cell carcinoma (BCC) of the skin are characterized morphologically by the proliferation of basaloid cells; however, BCCs are clinically associated with a more aggressive behavior. An accurate diagnosis of these lesions is essential for effective, timely treatment and appropriate therapeutic decisions. METHODS: This study includes 40 lesions. Bcl-2 and CD10 immunohistochemistry were performed in all cases and the patterns of expression were analyzed. RESULTS: Bcl-2 is useful for the detection of BCC with diffuse expression in nests of basaloid cells, but cannot distinguish between BCC with follicular differentiation and trichoblastoma, as both lesions show the same pattern with positive and negative areas. Conversely, CD10 expression can distinguish between trichoblastomas with peritumoral stromal staining and BCCs with epithelial staining. If both stromal and epithelial areas are stained, these cases are classified as BCC with follicular differentiation. CONCLUSIONS: CD10 is useful for distinguishing between BCC with widespread follicular differentiation and trichoblastomas.

[Association between microsatellite instability and clinico-pathological characteristics in sporadic colon cancer]. / Asociación entre la inestabilidad de microsatélites y las características clínicas y anatomopatológicas en pacientes con cáncer de colon esporádico.

BACKGROUND AND OBJECTIVE: Currently, colon cancer is a leading cause of cancer death world-wide. It progresses according to three molecular pathways, named suppressor, mutador and methylator. Microsatellite instability is a hallmark of the lack of reparation, of DNA mismatches and it characterizes a subset of colon tumors (unstable tumors, MSI). MSI-H patients (high degree of microsatellite instability) seem to share clinico-pathological differences with MSS (microsatellite stable) and MSI-L (low degree of microsatellite instability) patients. In this study, associations between high degree of microsatellite instability and pathological (location, mucinous content, differentiation grade, stages T3N0, stages II and III) and clinical features (response to chemotherapy, disease-free survival and overall survival) were evaluated. PATIENTS AND METHOD: 117 patients with sporadic colon cancer were classified into two populations (MSS/MSI-L and MSI-H) by using PCR and electrophoresis of seven microsatellites, according to the National Cancer Institute recommendations. RESULTS: MSI-H tumors tended to be located in the right colon (p = 0.022) and were of mucinous histologic type (p = 0.04). No differences in disease-free survival and overall survival between group of stage II and III patients with MSS/ MSI-L and corresponding ones with MSI-H colon cancer were found (p = 0.54, p = 0.37, respectively). Conversely, MSI-H patients with stage II colon cancer had a favourable prognosis (p = 0.027). Nevertheless, response to 5-fluorouracil (5-FU) and leucovorin was similar in MSS/ MSI-L and MSI-H groups (p = 0.38). CONCLUSIONS: MSI-H patients are characterized by certain pathological features; those MSI-H patients with a stage II seem to have a better prognosis than MSS/ MSI-L patients.