Genetic alterations in precancerous pancreatic lesions and their clinical implications.

Pancreatic adenocarcinoma, with an incidence/death ratio of 0.99, has the worst prognosis of all cancers. Risk factors associated with the sporadic form of pancreatic adenocarcinoma are unknown and less than 10% of patients receive curative treatment (surgery associated with radiation therapy or chemotherapy) with a low 5-year survival rate (10 to 20%). In more than 90% of patients, the tumor discovered at diagnosis is not resectable or has already metastasized. Thus, a better understanding of the etiology of pancreatic cancer is essential to identify new prognostic markers and new therapeutic targets. There is a wealth of data on the identification of genetic alterations associated with pancreatic cancer and their role in its development. This review will focus on the current knowledge of genetic alterations associated with two pancreatic lesions that can potentially evolve into pancreatic adenocarcinoma, Pancreatic Intraepithelial Neoplasia (PanIN) and Intraductal Papillary Mucinous Neoplasm (IPMN). These two lesions share a large panel of typical genetic alterations which are close to those found in pancreatic adenocarcinoma. A better understanding of these alterations may lead to therapeutic targets that could help prevent the progression of PanIN and IPMN to cancer.

Positive thyroid transcription factor 1 staining strongly correlates with survival of patients with adenocarcinoma of the lung.

This study investigated the relation between positive thyroid transcription factor 1 (TTF1) staining and survival of patients affected by primary adenocarcinoma (ADC) of the lung. Pathological tissue from consecutive ADC patients was collected from 2002 to 2004. The anti-TTF1 antibody (8G7G3/1, dilution of 1/200) was used. Thyroid transcription factor 1 staining was assessed for each tumour as positive or negative. Probability of survival was estimated by Kaplan-Meier and difference tested by log-rank test. A Cox's regression multivariate analysis was carried out. In all, 106 patients were studied (66% male, 69% PS0-1, 83% with stage III or IV). Tumours expressed positive TTF1 staining in 66% of cases. Multivariate analysis demonstrated an independent lower risk of death for patients whose tumour expresses positive TTF1 staining (HR = 0.51, 95% CI 0.30-0.85; P = 0.01) and higher grade of differentiation (HR = 0.40, 95% CI 0.24-0.68; P = 0.001). In conclusion, positive TTF1 staining strongly and independently correlates with survival of patients with primary ADC of the lung.