Background

Pancreatic ductal adenocarcinoma has proven to be one of the most chemo-resistant among all solid organ malignancies. Several mechanisms of resistance have been described, though few reports of strategies to overcome this chemo-resistance have been successful in restoring sensitivity to the primary chemotherapy (gemcitabine) and enter the clinical treatment arena.

Methods

We examined the ability of cellular arginine depletion through treatment with PEG-ADI to alter in vitro and in vivo cytotoxicity of gemcitabine. The effect on levels of key regulators of gemcitabine efficacy (e.g. RRM2, hENT1, and dCK) were examined.

Results

Combination of PEG-ADI and gemcitabine substantially increases growth arrest, leading to increased tumor response in vivo. PEG-ADI is a strong inhibitor of the gemcitabine-induced overexpression of ribonucleotide reductase subunit M2 (RRM2) levels both in vivo and in vitro, which is associated with gemcitabine resistance. This mechanism is through the abrogation of the gemcitabine-mediated inhibitory effect on E2F-1 function, a transcriptional repressor of RRM2.

Conclusion

The ability to alter gemcitabine resistance in a targeted manner by inducing metabolic stress holds great promise in the treatment of advanced pancreatic cancer.

Introduction

Despite some recent advances in treatment options, pancreatic cancer remains a devastating disease with poor outcomes. In a trend contrary to most malignancies, both incidence and mortality continue to rise due to pancreatic cancer. The majority of patients present with advanced disease and there are no treatment options for this stage that have demonstrated a median survival > 1 year. As the penultimate step prior to Phase III studies involving hundreds of patients, Phase II clinical trials provide an early opportunity to evaluate the efficacy of new treatments that are desperately needed for this disease.

Areas covered

This review covers the results of published Phase II clinical trials in advanced pancreatic adenocarcinoma published within the past 5 years. The treatment results are framed in the context of the current standards of care and the historic challenge of predicting Phase III success from Phase II trial results.

Expert opinion

Promising therapies remain elusive in pancreatic cancer based on recent Phase II clinical trial results. Optimization and standardization of clinical trial design in the Phase II setting, with consistent incorporation of biomarkers, is needed to more accurately identify promising therapies that warrant Phase III evaluation.

Objectives

To evaluate readmission rates and associated factors to identify potentially preventable readmissions.

Background

The decision to penalize hospitals for readmissions is compelling health care systems to develop processes to minimize readmissions. Research to identify preventable readmissions is critical to achieve these goals.

Methods

We performed a retrospective review of University HealthSystem Consortium database for cancer patients hospitalized from January 2010 to September 2013. Outcome measures were 7-, 14-, and 30-day readmission rates and readmission diagnoses. Hospital and disease characteristics were evaluated to evaluate relationships with readmission.

Results

A total of 2,517,886 patients were hospitalized for cancer treatment. Readmission rates at 7, 14, and 30 days were 2.2%, 3.7%, and 5.6%, respectively. Despite concern that premature hospital discharge may be associated with increased readmissions, a shorter initial length of stay predicted lower readmission rates. Furthermore, high-volume centers and designated cancer centers had higher readmission rates. Evaluating institutional data (N = 2517 patients) demonstrated that factors associated with higher readmission rates include discharge from a medical service, site of malignancy, and emergency primary admission. When examining readmission within 7 days for surgical services, the most common readmission diagnoses were infectious causes (46.3%), nausea/vomiting/dehydration (26.8%), and pain (6.1%).

Conclusions

A minority of patients after hospitalization for cancer-related therapy are readmitted with potentially preventable conditions such as nausea, vomiting, dehydration, and pain. However, most factors associated with readmission cannot be modified. In addition, high-volume centers and designated cancer centers have higher readmission rates, which may indicate that readmission rates may not be an appropriate marker for quality improvement.

Background

Volume of operative cases may be an important factor associated with improved survival for early-stage pancreatic cancer. Most high-volume pancreatic centers are also academic institutions, which have been associated with additional healthcare costs. We hypothesized that at high-volume centers, the value of the extra survival outweighs the extra cost.

Study design

This retrospective cohort study used data from the California Cancer Registry linked to the Office of Statewide Health Planning and Development database from January 1, 2004 through December 31, 2012. Stage I-II pancreatic cancer patients who underwent resection were included. Multivariable analyses estimated overall survival and 30-day costs at low- vs high-volume pancreatic surgery centers. The incremental cost-effectiveness ratio (ICER) and incremental net benefit (INB) were estimated, and statistical uncertainty was characterized using net benefit regression.

Results

Of 2,786 patients, 46.5% were treated at high-volume centers and 53.5% at low-volume centers. There was a 0.45-year (5.4 months) survival benefit (95% CI 0.21-0.69) and a $7,884 extra cost associated with receiving surgery at high-volume centers (95% CI $4,074-$11,694). The ICER was $17,529 for an additional year of survival (95% CI $7,997-$40,616). For decision-makers willing to pay more than $20,000 for an additional year of life, high-volume centers appear cost-effective.

Conclusions

Although healthcare costs were greater at high-volume centers, patients undergoing pancreatic surgery at high-volume centers experienced a survival benefit (5.4 months). The extra cost of $17,529 per additional year is quite modest for improved survival and is economically attractive by many oncology standards.

Background/aim

The Akt signaling pathway mediates a potent anti-apoptotic signal in pancreatic cancer and inhibition of this pathway has become an attractive mechanism to increase the efficacy of traditional chemotherapies. Autophagy is a lysosomal catabolic pathway by which eukaryotic cells recycle macromolecules and organelles. Although autophagy may function as a survival mechanism under metabolic stress conditions, it also serves as an alternate route to programmed cell death distinct from apoptosis. In the present study, we examined the role of autophagy in Akt-mediated regulation of cell death in pancreatic cancer.

Materials and methods

Mia-PaCa-2 and PANC-1 human pancreatic cancer cell lines were used in our experiments. The small-molecule inhibitor A-443654 was used to inhibit Akt, and rapamycin was used to inhibit mTOR. Autophagy was inhibited with Chloroquine and 3-methyladenine. Autophagy was assessed by immunoblotting for light chain-3 (LC-3) processing as well as fluorescence microscopy for autophagosome formation following transfection with a LC-3/GFP construct. Cell death was determined by fluorescence-activated cell sorting (FACS) with quantitation of the sub-G0 content.

Results

Inhibition of either Akt or mTOR induced autophagy; inhibition of Akt but not of mTOR led to traditional caspase-mediated apoptosis. When autophagy was inhibited, cell death was abrogated following Akt, but not mTOR, inhibition.

Conclusion

The Akt signaling pathway regulates both autophagy and apoptosis through divergent pathways; mTOR mediates autophagy signaling but appears to be un-involved in cell death. Autophagy appears to play a role in the regulation of cell survival by Akt, but only when proximal signaling pathways not involving mTOR are simultaneously activated.

Objectives

Comorbid psychiatric illness has been associated with worse outcomes after some major surgical procedures. We hypothesized that patients with preexisting mood disorders would have worse postoperative and oncologic outcomes after pancreatic cancer resection.

Methods

This retrospective cohort study analyzed Surveillance, Epidemiology, and End Results patients with resectable pancreatic adenocarcinoma. A preexisting mood disorder was classified if a patient was diagnosed and/or treated with medication approved for depression/anxiety within 6 months before surgery.

Results

Of 1305 patients, 16% had a preexisting mood disorder. Mood disorders had no impact on hospital length of stay (12.9 vs 13.2 days, P = 0.75), 30-day complications (26% vs 22%, P = 0.31), 30-day readmissions (26% vs 21%, P = 0.1), or mortality (30 days: 3% vs 4%, P = 0.35); only an increased 90-day readmissions rate (42% vs 31%, P = 0.001) was observed. No effect on adjuvant chemotherapy receipt (62.5% vs 69.2%, P = 0.06) or survival (24 months, 43% vs 39%, P = 0.44) was observed.

Conclusions

Preexisting mood disorders influenced 90-day readmissions after pancreatic resection, but not other postoperative or oncologic outcomes. These findings suggest that affected patients should be expected to have outcomes similar to patients without mood disorders.

Background

Secondary cancers account for 16% of all new cancer diagnoses, with breast cancer (BC) the most common secondary cancer. We have shown that secondary BC has unique characteristics and decreased survival compared with primary BC in adolescent and young adults (AYA; 15-39 years old). However, older BC populations are less well studied.

Methods

Females (age ≥ 15 years) diagnosed with primary BC during 1991-2015 (n = 377,167) and enrolled in the California Cancer Registry were compared with those with secondary BC (n = 37,625) by age (15-39, 40-64, ≥ 65 years). We examined BC-specific survival (BCSS) accounting for other causes of death as a competing risk using multivariable Cox proportional hazards regression.

Results

Most secondary BC patients were of older age (15-39, n = 777; 40-64, n = 15,848; ≥ 65, n = 21,000). Compared with primary BC treatment, secondary BCs were more often treated with mastectomy and less often with chemotherapy and/or radiation. BCSS was shorter in secondary BC patients than primary BC patients, but the survival difference between secondary and primary BC diminished with age [15-39 hazard ratio (HR): 2.09, 95% confidence interval (CI) 1.83-2.39; 40-64 HR: 1.51; 95% CI 1.44-1.58; ≥ 65 HR: 1.14; 95% CI 1.10-1.19]. Survival differences were most pronounced in women with hormone receptor positive disease and Hispanic and Asian/Pacific Islanders 40-64 years of age.

Conclusions

When BC is diagnosed following a prior cancer of any organ site, BCSS is worse than when compared with patients for whom BC is the primary diagnosis, suggesting that we may need to tailor our treatments for women with secondary BC.

Background

The impact of surgery on end of life care for patients with disseminated malignancy (DMa) is incompletely characterized. The purpose of this study was to evaluate postoperative outcomes impacting quality of care among DMa patients, specifically prolonged length of hospital stay, readmission, and disposition.

Methods

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for years 2011-2012. DMa patients were matched to non-DMa patients with comparable clinical characteristics and operation types. Primary hepatic operations were excluded, leaving a final cohort of 17,972 DMa patients. The primary outcomes were analyzed using multivariate Cox regression models.

Results

DMa patients represented 2.1% of all ACS-NSQIP procedures during the study period. The most frequent operations were bowel resections (25.3%). Compared to non-DMa matched controls, DMa patients had higher rates of postoperative overall morbidity (24.4% vs. 18.7%, p<0.001), serious morbidity (14.9% vs. 12.0%, p<0.001), mortality (7.6% vs. 2.5%, p<0.001), prolonged length of stay (32.2% vs. 19.8%, p<0.001), readmission (15.7% vs. 9.6%, p<0.001), and discharges to facilities (16.2% vs. 12.9%, p<0.001). Subgroup analyses of patients by procedure type showed similar results. Importantly, DMa patients who did not experience any postoperative complication experienced significantly higher rates of prolonged length of stay (23.0% vs. 11.8%, p<0.001), readmissions (10.0% vs. 5.2%, p<0.001), discharges to a facility (13.2% vs. 9.5%, p<0.001), and 30-day mortality (4.7% vs. 0.8%, p<0.001) compared to matched non-DMa patients.

Conclusion

Surgical interventions among DMa patients are associated with poorer postoperative outcomes including greater postoperative complications, prolonged length of hospital stay, readmissions, disposition to facilities, and death compared to non-DMa patients. These data reinforce the importance of clarifying goals of care for DMa patients, especially when acute changes in health status potentially requiring surgery occur.

Background

Surgical morbidity and mortality (M&M) for patients with disseminated malignancy (DMa) is high, and some have questioned the role of surgery. Therefore, we sought to characterize temporal trends in M&M among DMa patients, hypothesizing that surgical intervention would remain prevalent.

Methods

We queried the American College of Surgeons National Surgical Quality Improvement Program from 2006-2010. Excluding patients undergoing a primary hepatic operation, we identified 21,755 patients with DMa. Parametric and/or nonparametric statistics and logistic regression were used to evaluate temporal trends and predictors of M&M.

Results

The prevalence of surgical intervention for DMa declined slightly over the time period, from 1.9%-1.6% of all procedures (P < 0.01). Among DMa patients, the most frequent operations performed were bowel resection, other gastrointestinal procedures, and multivisceral resections, these all showed small statistically significant decreases over time (P < 0.01). The rate of emergency operations also decreased (P < 0.01). In contrast, the rate of preoperative independent functional status rose, whereas the rate of preoperative weight loss and sepsis decreased (P < 0.01). Rates of 30-d morbidity (33.7 versus 26.6%), serious morbidity (19.8 versus 14.2%), and mortality (10.4 versus 9.3%) all decreased over the study period (P < 0.05). Multivariate analysis identified standard predictors (e.g., impaired functional status, preoperative weight loss, preoperative sepsis, and hypoalbuminemia) of worse 30-d M&M.

Conclusions

Thirty-day morbidity, serious morbidity, and mortality have decreased incrementally for patients with DMa undergoing surgical intervention, but surgical intervention remains prevalent. These data further highlight the importance of careful patient selection and goal-directed therapy in patients with incurable malignancy.

Re-excision rates for breast cancer lumpectomy procedures are currently nearly 25% due to surgeons relying on inaccurate or incomplete methods of evaluating specimen margins. The objective of this study was to determine if cancer could be automatically detected in breast specimens from mastectomy and lumpectomy procedures by a classification algorithm that incorporated parameters derived from fluorescence lifetime imaging (FLIm). This study generated a database of co-registered histologic sections and FLIm data from breast cancer specimens (N  =  20) and a support vector machine (SVM) classification algorithm able to automatically detect cancerous, fibrous, and adipose breast tissue. Classification accuracies were greater than 97% for automated detection of cancerous, fibrous, and adipose tissue from breast cancer specimens. The classification worked equally well for specimens scanned by hand or with a mechanical stage, demonstrating that the system could be used during surgery or on excised specimens. The ability of this technique to simply discriminate between cancerous and normal breast tissue, in particular to distinguish fibrous breast tissue from tumor, which is notoriously challenging for optical techniques, leads to the conclusion that FLIm has great potential to assess breast cancer margins. Identification of positive margins before waiting for complete histologic analysis could significantly reduce breast cancer re-excision rates.