Long-term outcomes for neoadjuvant versus adjuvant chemotherapy in early breast cancer: meta-analysis of individual patient data from ten randomised trials

Background Neoadjuvant chemotherapy (NACT) for early breast cancer can make breast-conserving surgery more feasible and might be more likely to eradicate micrometastatic disease than might the same chemotherapy given after surgery. We investigated the long-term benefits and risks of NACT and the influence of tumour characteristics on outcome with a collaborative meta-analysis of individual patient data from relevant randomised trials. Methods We obtained information about prerandomisation tumour characteristics, clinical tumour response, surgery, recurrence, and mortality for 4756 women in ten randomised trials in early breast cancer that began before 2005 and compared NACT with the same chemotherapy given postoperatively. Primary outcomes were tumour response, extent of local therapy, local and distant recurrence, breast cancer death, and overall mortality. Analyses by intention-to-treat used standard regression (for response and frequency of breast-conserving therapy) and log-rank methods (for recurrence and mortality). Findings Patients entered the trials from 1983 to 2002 and median follow-up was 9 years (IQR 5–14), with the last follow-up in 2013. Most chemotherapy was anthracycline based (3838 [81%] of 4756 women). More than two thirds (1349 [69%] of 1947) of women allocated NACT had a complete or partial clinical response. Patients allocated NACT had an increased frequency of breast-conserving therapy (1504 [65%] of 2320 treated with NACT vs 1135 [49%] of 2318 treated with adjuvant chemotherapy). NACT was associated with more frequent local recurrence than was adjuvant chemotherapy: the 15 year local recurrence was 21·4% for NACT versus 15·9% for adjuvant chemotherapy (5·5% increase [95% CI 2·4–8·6]; rate ratio 1·37 [95% CI 1·17–1·61]; p=0·0001). No significant difference between NACT and adjuvant chemotherapy was noted for distant recurrence (15 year risk 38·2% for NACT vs 38·0% for adjuvant chemotherapy; rate ratio 1·02 [95% CI 0·92–1·14]; p=0·66), breast cancer mortality (34·4% vs 33·7%; 1·06 [0·95–1·18]; p=0·31), or death from any cause (40·9% vs 41·2%; 1·04 [0·94–1·15]; p=0·45). Interpretation Tumours downsized by NACT might have higher local recurrence after breast-conserving therapy than might tumours of the same dimensions in women who have not received NACT. Strategies to mitigate the increased local recurrence after breast-conserving therapy in tumours downsized by NACT should be considered—eg, careful tumour localisation, detailed pathological assessment, and appropriate radiotherapy

Asymmetry and collusion in sequential procurement: a 'Large lot last' policy

Sequential procurement of multiple contracts/lots is widespread and often regularly repeated. We analyze how sequentiality and its interaction with asymmetries across bidders and lots affect the sustainability of supplier/bidder collusion. Sequential procurement stabilizes supplier collusion (compared to simultaneous procurement) by allowing not only to identify or punish deviations within the sequence, but also to allocate the “last lot” to the bidder with the highest incentive to defect. We then analyze how to counteract these effects by exploiting (or creating) asymmetries in the value of lots, finding that the most effective policy procures the most valuable lot at the end of each sequenc

Teaching an old dog a new trick: Reserve price and unverifiable quality in repeated procurement

This paper shows that, in a repeated competitive procurement, a buyer can use the reserve price in a low-price auction as a "public"-hence nondiscriminatory-incentive device to elicit unverifiable quality. We study a model with many firms and one buyer, who is imperfectly informed on the firms' costs. When firms are ex ante identical, the provision of quality is sustained by a sufficiently high reserve price to reward firms for the quality provision and by the threat of setting a low reserve price forever, if quality is not delivered. The buyer can elicit the desired level of unverifiable quality provided her baseline valuation of the project is not too high and the net benefit from unverifiable quality is not too low. These results are robust to firms' heterogeneity in their time preferences when the punishment for a deviation is finite but sufficiently long

Retaliatory Equilibria in a Japanese Ascending Auction for Multiple Objects

Ascending auctions for multiple objects, Clock auctions, FCC auctions, Collusion, Retaliation, C72, D44,

Regulating joint bidding in procurement

Joint bidding is the practice of two or more independent suppliers submitting a single bid, a widespread practice in private and public procurement. This practice may generate efficiencies through synergies and information sharing, but may also be abused to reduce the number of competitors or-even worse-to facilitate or enforce collusion among them; therefore, it is often regulated. In this paper, we first present results from a survey on the regulation of joint bidding in European public procurement, documenting how the existence and the type of regulation differ across countries, and that-where present-regulation is often related to the ability of an individual firm to be admitted as a solo bidder. Borrowing from the theories of joint bidding in auctions and of horizontal mergers and joint ventures in oligopoly, we then review the basic economics of bidding consortia and the effects that these can have in terms of bidding competition, coordination among firms, risk management, exploitation of other synergies, and entry. Finally, we assess the relative degrees of restrictiveness of several practical criteria that could be used to create consistent regulatory requirements for bidding consortia in public procurement. The only strong conclusion that we can draw is that there is an urgent need for further theoretical and empirical or experimental research on this very important issue for public procurement. © The Author (2008). Published by Oxford University Press. All rights reserved