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In the newsvendor game, the expected-profit-maximizing order quantity is higher in the demand interval when the per-unit profit margin is high and lower in the demand interval when the per-unit profit margin is low. However, laboratory experiments show a “pull-to-center” effect: average order quantities are too low when they should be high and vice versa. We replicate this pull-to-center effect in laboratory experiments and construct an adaptive learning model that incorporates memory, reinforcement, and probabilistic choice to explain individual decisions. The intuition underlying the model's prediction is that the most recent demand observation is more likely to have been greater than the optimal order quantity if the optimal order quantity is low, in which case a recency bias tends to pull the order quantity upward. A countervailing downward pull exists if the optimal order quantity is high. The recency effect may be augmented by a reinforcement bias, which causes subjects to focus more on the profitability of decisions they actually make and less on counterfactual payoffs that would have resulted from other order quantities. The predictions of this model track the observed data patterns across treatments. A pull-to-center pattern is also observed in designs involving doubled payoffs and reduced order frequency.

Sarcopenia in women was a predictor of major complications after radical cystectomy. Further research confirming sarcopenia as a useful predictor of complications would support the development of targeted interventions to mitigate the untoward effects of sarcopenia before cancer surgery.

Watchful waiting for renal masses is a reasonable option for appropriately selected patients, especially those with competing comorbidities. Delayed intervention does not appear to adversely impact pathological outcomes.

BACKGROUND: Bladder cancer is notable for a striking heterogeneity of disease-specific risks. Among the approximately 75% of incident cases found to be superficial to the muscularis propria at the time of presentation (non-muscle-invasive bladder cancer), the risk of progression to the lethal phenotype of muscle-invasive disease is strongly associated with stage and grade of disease. Given the suggestion of an increasing percentage of low-risk cases in hospital-based registry data in recent years, the authors hypothesized that population-based data may reveal changes in the stage distribution of early-stage cases. METHODS: Surveillance, Epidemiology, and End Results (SEER) data were used to examine trends for the stage-specific incidence of bladder cancer between 1988 and 2006, adjusted for age, race, and sex, using Joinpoint and nonparametric tests. RESULTS: The adjusted incidence rate of papillary noninvasive (Ta) predominantly low grade (77%) disease was found to increase from 5.52 to 9.09 per 100,000 population (P <.0001), with an average annual percentage change of +3.3. Over the same period, concomitant, albeit smaller, decreases were observed for flat in situ (Tis) and lamina propria-invasive (T1) disease (2.57 to 1.19 and 6.65 to 4.61 per 100,000 population [both P <.0001]; average annual percent change of −5.0 and −1.6, respectively). The trend was most dramatic among patients in the oldest age strata, suggesting a previously unappreciated cohort phenomenon. CONCLUSIONS: The findings of the current study should motivate further epidemiological investigations of differential associations of genetic and environmental factors with different bladder cancer phenotypes as well as further scrutiny of clinical practice guideline recommendations for the growing subgroup of predominantly older patients with lower-risk disease.

Background The comprehensive geriatric assessment (CGA) has developed as an important prognostic tool to risk stratify older adults and has recently been applied to the surgical field. In this systematic review, we examined the utility of CGA components as predictors of adverse outcomes among geriatric patients undergoing major oncologic surgery. Materials and Methods MEDLINE, Embase, and the Cochrane Library were searched for prospective studies examining the association of components of the CGA with specific outcomes among geriatric patients undergoing elective oncologic surgery. Outcome parameters included 30-day post-operative complications, mortality, and discharge to a non-home institution. Results The initial search identified 178 potentially relevant articles, with six studies meeting inclusion criteria. Deficiencies in instrumental activities of daily living (IADLs), ADLs, fatigue, cognition, frailty, and cognitive impairment were associated with increased post-operative complications. No CGA predictors were identified for post-operative mortality while frailty, deficiencies in IADLs, and depression predicted discharge to a non-home institution. Conclusions Across a variety of surgical oncologic populations and cancer types, components of the CGA appear to be predictive of post-operative complications and discharge to a non-home institution. These results argue for inclusion of focused geriatric assessments as part of routine pre-operative care in the geriatric surgical oncology population.

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