p53 over-expression identifies a subset of nodal peripheral T-cell lymphomas with a distinctive biological profile and poor clinical outcome.

Peripheral T-cell lymphomas (PTCL) are usually characterized by aggressive clinical behaviour and poor clinical outcome, but their biological background has not been extensively investigated to date, due to their low incidence, about 10% of all non-Hodgkin's lymphoma cases in Western countries, and also to the paucity of specific molecular-genetic abnormalities. Neverthless, there is increasing biological and clinical evidence that primary nodal PTCL should be considered separately from extra-nodal cases, but little is known about biological factors of possible clinical and prognostic impact. This immunohistochemical study has analysed the expression of p53, Mdm2, p21(WAF1), BCL-2 and p-glycoprotein (MDR-1 gene product) in a series of 45 cases of nodal peripheral T-cell lymphomas (PTCL) with 'high-grade' histology. The immunohistochemical findings were then correlated with proliferative activity and clinical outcome. p53 was over-expressed in 13 cases (28.9%). p53 positive cases showed significantly higher proliferative activity (p<0.01), more frequent expression of Bcl-2 (p<0.01) and less frequent expression of p21(WAF1) than p53 negative cases. Mdm2 and p-glycoprotein were expressed in 4/13 (30.8%) and 8/13 (61.5%) p53 positive cases respectively, and in none (0%) of the p53 negative cases (p<0.01). Analysis of the survival curves showed that p53 positive cases were associated with a significantly poorer clinical outcome than p53 negative cases, in terms of both overall survival (p=0.0032) and event-free survival (p=0.0004). Furthermore, multivariate analysis showed that p53 expression was the most important independent prognostic variable. These findings indicate that p53 over-expression identifies a subset of nodal PTCL cases with a distinctive biological profile (higher proliferative activity, less frequent expression of p21(WAF1) and more frequent expression of Bcl-2, Mdm2 and p-glycoprotein than p53 negative cases) and poor clinical outcome. The immunohistochemical analysis of p53 expression is a simple, rapid and low-cost method which may provide information of potential clinical and prognostic value in nodal peripheral T-cell lymphomas.

[Renal oncocytoma: its differential diagnosis and the indications for surgical treatment]. / Oncocitoma renale: diagnosi differenziale ed indicazioni al trattamento chirurgico.

The authors report an uncommon renal oncocytoma rate stressing difficulties that modern diagnostic modalities meet in a correct preoperative differential diagnosis with nephrocarcinoma. Oncocytoma is a low multifocal involvement. Surgical treatment is the primary choice, nephrectomy about localized monofocal lesions in advisable, with short and long term positive outcomes. In ambilateral involvement case without malignancy evident signs (scarce likelihood to infiltrate nephritic capsule, without lymphoadenopathy) conservative operations with partial resections are suggested with a five years survival from 84 to 96%.

A case of recurrent dermatofibrosarcoma protuberans.

The authors report a case of DFSP with one true and one successive false recurrence. The characteristics of this tumour are reviewed together with the current trends of therapy.