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Abstract This review summarizes syntheses of S,N-heteropentacenes, i.e. electron-rich sulfur and nitrogen-embedding pentacycles, and briefly highlights selected applications in molecular electronics. Depending on the anellation mode and the number of incorporated heteroatoms, electron density can be raised by increasing nitrogen incorporation and polarizability is manifested by the sulfur content. In comparison to triacene analogues, the conjugation pathways of S,N-heteropentacenes are increased and the favorable acene-typical crystallization behavior allows for diverse application in organic electronics. Furthermore, substitution patterns allow fine-tuning the electronic properties, extending the π-systems, and supplying structural elements for further application. 1 Introduction 2 Thiophene-Centered S,N-Heteropentacenes 2.1 Dipyrrolo-Fused Thiophenes 2.2 Diindolo-Fused Thiophenes 3 Pyrrole-Centered S,N-Heteropentacenes 3.1 Dithieno-Fused Pyrroles 3.2 Bis[1]benzothieno-Fused Pyrrole 4 Fused 1,4-Thiazines 4.1 Dinaphtho-Fused 1,4-Thiazines 4.2 Bis[1]benzothieno-Fused 1,4-Thiazines 5 Conclusions and Outlook

Background: Local recurrence of pancreatic cancer occurs in 80% of patients within 2 years after potentially curative resections. Around 30% of patients have isolated local recurrence (ILR) without evidence of metastases. In spite of localized disease these patients usually only receive palliative chemotherapy and have a short survival., Purpose: To evaluate the outcome of surgery as part of a multimodal treatment for ILR of pancreatic cancer., Methods: All consecutive operations performed for suspected ILR in our institution between October 2001 and October 2009 were identified from a prospective database. Perioperative outcome, survival, and prognostic parameters were assessed., Results: Of 97 patients with histologically proven recurrence, 57 (59%) had ILR. In 40 (41%) patients surgical exploration revealed metastases distant to the local recurrence. Resection was performed in 41 (72%) patients with ILR, while 16 (28%) ILR were locally unresectable. Morbidity and mortality were 25 and 1.8% after resections and 10 and 0% after explorations, respectively. Median postoperative survival was 16.4 months in ILR versus 9.4 months in metastatic disease (p < 0.0001). In ILR median survival was significantly longer after resection (26.0 months) compared with exploration without resection (10.8 months, p = 0.0104). R0 resection was achieved in 18 patients and resulted in 30.5 months median survival. Presence of metastases, incomplete resection, and high preoperative CA 19-9 serum values were associated with lesser survival., Conclusions: Resection for isolated local recurrence of pancreatic cancer is feasible, safe, and associated with favorable survival outcome. This concept warrants further evaluation in other institutions and in randomized controlled trials.

Background: For pancreatic cancer, complete macroscopic resection in combination with chemotherapy is the only potentially curative treatment. Many patients present with locally advanced cancers deemed unresectable. We sought to assess the results of exploration after neoadjuvant therapy for locally advanced possibly unresectable pancreatic cancer., Methods: From a prospective database, all consecutive patients undergoing operation from October 2001 to December 2009 after neoadjuvant therapy for locally advanced pancreatic cancer were identified. Main criteria for "unresectability" were infiltration of the celiac axis or superior mesenteric artery. Resection rates, perioperative results, and survival were analyzed., Results: Of 257 patients, 199 (77.4%) had received neoadjuvant chemoradiation, and 58 (22.6%) chemotherapy only. Of 257 patients, 120 (46.7%) underwent successful resection, whereas 137 patients underwent exploration only; 47 (39.2%) multivisceral and 45 (37.5%) vascular resections (12 arterial reconstructions) were performed. There were 6 (5%) ypT0 neoplasms, 36 (30.0%) R0, 61 (50.8%) R1, and 16 (13.3%) R2 resections. The median follow-up of surviving patients (n = 22) was 22 months. Median postoperative survival was greater after resection (12.7 months) than after exploration alone (8.8 months; P < .0001). Median postoperative survival was 24.6 months after R0, 11.9 months after R1, and 8.9 months after R2 resection. The 3-year survival rate after R0 resection was 24%. To determine survival after start of neoadjuvant therapy, 3.7 months (median) have to be added., Conclusion: In locally advanced, unresectable pancreatic cancer, R0/R1 resections can be achieved in up to 40% of patients who undergo operation after neoadjuvant therapy. In these cases, survival rates are similar to those observed for initially resectable pancreatic cancer., (Copyright © 2012 Mosby, Inc. All rights reserved.)