Intraductal papillary mucinous tumors (IPMTs) of the pancreas may be meaningfully construed as representing 2 clinically distinct subtypes: main duct tumors (MDT) and branch duct tumors (BDT).

NAC-GS was well tolerated and safe when used in a multi-institutional setting. The R0 resection rate and the 2-year survival rate analysis are encouraging for patients with resectable and borderline PDAC.

The mechanism of metastasis formation remains still largely unknown. Many studies underline the importance and complexity of the initial arrest of the circulating tumour cells in the target organ, a key stage in metastasis occurrence. In our study, we evaluated by visual means the metastasis formation using an in vivo microscopy system in a murine model. Moreover, we investigated the involvement of P-selectin in these processes using immunohistochemistry and P-selectin knockout mice. The present study offers direct evidence of distinct pathways for tumour metastasis formation by a lymphoma cell – EL-4 and a solid tumour cell – C26. Off-line analysis of the images and histological data confirmed that mechanical entrapment of the solid tumour cell, which had a bigger diameter than that of the liver sinusoids, promoted metastasis without any detectable involvement of adhesion molecules. On the other hand, we observed that lymphoma cells, in spite of their smaller diameter as compared to the sinusoids, promoted liver metastasis as well, but with the essential participation in their arrest of P-selectin, indicating an adhesion molecule-mediated pathway. © 2001 Cancer Research Campaign http://www.bjcancer.com

Dendritic cells (DC) are potent antigen-presenting cells that are important for the priming of antitumor cytotoxic T cells. Recent reports suggest that DC may also have direct cytotoxic effector functions against selected tumor-cell lines by mechanisms that are dependent on dendritic cell-tumor cell contact in vitro. The authors report that ex vivo-generated murine DC induce the apoptosis of a panel of syngeneic and allogeneic murine tumors. Apoptosis of the MCA205 fibrosarcoma tumor-cell line by C57BL/6-derived DC was not mediated by Fas/FasL interactions and, in contrast to other studies, DC-tumor cell contact was not required to effect tumor-cell killing by DC. Therefore, the authors postulated that tumor-cell killing was mediated by an apoptotic factor that was secreted by DC. Even though DC did not secrete such apoptotic cytokines as interferon-alpha or tumor necrosis factor-alpha, they did secrete nitric oxide, and tumor apoptosis was partially abrogated by the nitric oxide synthase antagonist NG-monomethyl-L-arginine. Therefore, the authors' data demonstrate a novel mechanism for DC-induced tumor-cell apoptosis that does not require DC-tumor cell contact and is partially mediated by nitric oxide.