Effects of Scavenging, Entrainment, and Aqueous Chemistry on Peroxides and Formaldehyde in Deep Convective Outflow Over the Central and Southeast United States.

Deep convective transport of gaseous precursors to ozone (O3) and aerosols to the upper troposphere is affected by liquid phase and mixed-phase scavenging, entrainment of free tropospheric air and aqueous chemistry. The contributions of these processes are examined using aircraft measurements obtained in storm inflow and outflow during the 2012 Deep Convective Clouds and Chemistry (DC3) experiment combined with high-resolution (dx ≤ 3 km) WRF-Chem simulations of a severe storm, an air mass storm, and a mesoscale convective system (MCS). The simulation results for the MCS suggest that formaldehyde (CH2O) is not retained in ice when cloud water freezes, in agreement with previous studies of the severe storm. By analyzing WRF-Chem trajectories, the effects of scavenging, entrainment, and aqueous chemistry on outflow mixing ratios of CH2O, methyl hydroperoxide (CH3OOH), and hydrogen peroxide (H2O2) are quantified. Liquid phase microphysical scavenging was the dominant process reducing CH2O and H2O2 outflow mixing ratios in all three storms. Aqueous chemistry did not significantly affect outflow mixing ratios of all three species. In the severe storm and MCS, the higher than expected reductions in CH3OOH mixing ratios in the storm cores were primarily due to entrainment of low-background CH3OOH. In the air mass storm, lower CH3OOH and H2O2 scavenging efficiencies (SEs) than in the MCS were partly due to entrainment of higher background CH3OOH and H2O2. Overestimated rain and hail production in WRF-Chem reduces the confidence in ice retention fraction values determined for the peroxides and CH2O.

Lessons learned from the evolution of the laparoscopic revolution.

After 100 years of practice, the face of general surgery changed forever when laparoscopic cholecystectomy was introduced. The impact was felt in how new procedures were taught and learned, proficiency determined, and credentials established. In addition, the revolution of laparoscopic surgery brought to bear ethical considerations and the harsh reality of medical legal and economic ramifications of new technology introduction. Finally, minimally invasive surgery challenged dogma of traditional perioperative care, allowing streamlining of postoperative recovery.

Outcomes following resection of pancreatic adenocarcinoma: 20-year experience at a single institution.

BACKGROUND: Pancreatectomy for ductal adenocarcinoma has been performed with increasing frequency since the late 1980s as postoperative mortality decreased and long-term survival became more common. However, the belief persists among some clinicians that pancreatectomy offers little survival benefit. This report reviews our institutional experience with pancreatectomy for pancreatic adenocarcinoma and provides a critical overview of the controversies regarding the benefits of surgical intervention for patients who are candidates for curative resection. METHODS: We determined the survival of 142 patients who underwent pancreatectomy for ductal adenocarcinoma with curative intent (stage IA-IIB) at Moffitt Cancer Center during the last two decades by using data obtained from review of the medical record, the Moffitt Cancer Registry, and the Social Security Death Index. Histologic diagnosis was confirmed by expert review of stained sections cut from fixed surgical specimens. RESULTS: In the 137 patients who survived at least 30 days after surgery, the median survival was 21.2 months after resection, with Kaplan-Meier 3- and 5-year disease-specific survival rates of 36% and 32%, respectively. One patient has survived without evidence of recurrent disease for more than 15 years after pancreatectomy. Survival for patients greater than 75 year of age did not differ from that of younger patients. The postoperative mortality rate was 1.5% during the most recent years of highest operative volume (2003 to 2006) and 3.5% for the entire patient cohort. CONCLUSIONS: Review of our 20-year experience with resection of pancreatic adenocarcinoma indicates that pancreatectomy with curative intent offers a real chance of long-term survival to patients with this highly lethal disease for which there is no other curative modality.

32P as an adjunct to standard therapy for locally advanced unresectable pancreatic cancer: a randomized trial.

This prospective randomized trial was undertaken to determine the added efficacy of (32)P in treating locally advanced unresectable pancreatic cancer. Thirty patients with biopsy proven locally advanced unresectable adenocarcinoma of the pancreas were assessable after receiving 5-fluorouracil and radiation therapy with or without (32)P, followed by gemcitabine. Intratumoral (32)P dose was determined by tumor size and volume and was administered at months 0, 1, 2, 6, 7, and 8. Tumor cross-sectional area and liquefaction were determined at intervals by computed tomography scan. Tumor liquefaction occurred in 78% of patients receiving (32)P and in 8% of patients not receiving (32)P, although tumor cross-sectional area did not decrease. Serious adverse events occurred more often per patient for patients receiving (32)P (4.2 +/- 3.1 vs. 1.8 +/- 1.9; p = 0.03) leading to more hospitalizations. Death was because of disease progression (23 patients), gastrointenstinal hemorrhage (4 patients), and stroke (1 patient). One patient not receiving (32)P and one receiving (32)P are alive at 28 and 13 months, respectively. (32)P did not prolong survival (7.4 +/- 5.5 months with (32)P vs. 11.5 +/- 8.0 months without (32)P, p = 0.16). (32)P promoted tumor liquefaction, but did not decrease tumor size. Intratumoral (32)P was associated with more serious adverse events and did not improve survival for locally advanced unresectable pancreatic cancer.

Improved outcome with cytoreduction versus embolization for symptomatic hepatic metastases of carcinoid and neuroendocrine tumors.

BACKGROUND: Few data exist regarding outcomes after resection versus embolic treatment of symptomatic metastatic carcinoid and neuroendocrine tumors. The purpose of this study was to determine whether cytoreduction provides any benefit over embolic management of diffuse neuroendocrine tumors. METHODS: A prospective database of 734 patients treated at our institution was retrospectively queried for symptomatic metastatic tumors treated with embolization or cytoreduction. Patients were compared with regard to pretreatment performance status, relief of symptoms, and survival. RESULTS: A total of 120 patients were identified: 59 undergoing embolization and 61 undergoing cytoreduction. Twenty-three patients had palliative cytoreduction (gross residual disease). Pretreatment performance status (Eastern Cooperative Oncology Group) was similar for both groups: .7+/-.70 (embolization) versus .8+/-.72 (cytoreduction; P=.27). Complete symptomatic relief was observed in 59% and partial relief in 32% of patients who underwent embolization, with a mean symptom-free interval of 22+/-13.6 months. A total of 69% of patients who underwent cytoreduction had complete symptomatic relief, and 23% had partial relief (P=.08 vs. embolization). The mean duration of relief was 35+/-22.0 months (P<.001 vs. embolization). The mean survival for the patients who underwent embolization was 24+/-15.8 months versus 43+/-26.1 months for those who underwent cytoreduction (P<.001). Survival in patients who underwent palliative cytoreduction was 32+/-18.9 months (P<.001 vs. embolization), whereas it was 50+/-27.6 months in patients who underwent curative resection (P<.001 vs. embolization; P<.001 vs. palliative). CONCLUSIONS: Cytoreduction for metastatic neuroendocrine tumors resulted in improved symptomatic relief and survival when compared with embolic therapy in this nonrandomized study. Cytoreduction should be pursued whenever possible even if complete resection may not be achievable.

Stage does not predict survival after resection of hilar cholangiocarcinomas promoting an aggressive operative approach.

INTRODUCTION: Staging systems have been developed to predict survival after resection of hilar cholangiocarcinoma. Notably, they have not been validated nor compared for relative predictive ability. METHODS: Forty-two patients underwent resection of hilar cholangiocarcinoma and have been followed through a prospectively collected database. The tumors were staged using the Bismuth-Corlette, Blumgart, and American Joint Committee on Cancer (AJCC) systems, and a significant relationship with survival was sought. RESULTS: Eleven patients were treated by extrahepatic biliary resection alone, while 31 required extrahepatic biliary resections with in-continuity hepatic resections. All patients underwent adjuvant therapy. To date, 30 patients have died with a mean survival time of 30 months +/- 35.0 (SD). Twelve patients are alive with a mean survival of 90 months +/- 61.8. By regression analysis, none of the staging systems had a significant relationship with survival (Bismuth: P = .64; Blumgart: P = .66; AJCC: P = .31). CONCLUSIONS: Most patients with hilar cholangiocarcinoma require in-continuity hepatic resections. Survival after resection promotes an aggressive approach, with cure in as many as 30%. Staging systems should not impact the decision to operate or postoperative management, as all tumors should be aggressively resected and all patients should receive adjuvant treatment.

TIPS versus peritoneovenous shunt in the treatment of medically intractable ascites: a prospective randomized trial.

OBJECTIVE: We undertook a prospective randomized clinical trial comparing TIPS to peritoneovenous (PV) shunts in the treatment of medically intractable ascites to establish relative efficacy and morbidity, and thereby superiority, between these shunts. METHODS: Thirty-two patients were prospectively randomized to undergo TIPS or peritoneovenous (Denver) shunts. All patients had failed medical therapy. RESULTS: After TIPS versus peritoneovenous shunts, median (mean +/- SD) duration of shunt patency was similar: 4.4 months (6 +/- 6.6 months) versus 4.0 months (5 +/- 4.6 months). Assisted shunt patency was longer after TIPS: 31.1 months (41 +/- 25.9 months) versus 13.1 months (19 +/- 17.3 months) (P < 0.01, Wilcoxon test). Ultimately, after TIPS 19% of patients had irreversible shunt occlusion versus 38% of patients after peritoneovenous shunts. Survival after TIPS was 28.7 months (41 +/- 28.7 months) versus 16.1 months (28 +/- 29.7 months) after peritoneovenous shunts. Control of ascites was achieved sooner after peritoneovenous shunts than after TIPS (73% vs. 46% after 1 month), but longer-term efficacy favored TIPS (eg, 85% vs. 40% at 3 years). CONCLUSION: TIPS and peritoneovenous shunts treat medically intractable ascites. Absence of ascites after either is uncommon. PV shunts control ascites sooner, although TIPS provides better long-term efficacy. After either shunt, numerous interventions are required to assist patency. Assisted shunt patency is better after TIPS. Treating medically refractory ascites with TIPS risks early shunt-related mortality for prospects of longer survival with ascites control. This study promotes the application of TIPS for medically intractable ascites if patients undergoing TIPS have prospects beyond short-term survival.

Recollections of Robert M. Zollinger, M.D.

Remembering Dr. Robert M. Zollinger are Dr. Larry C. Carey, professor of surgery at the University of South Florida, in Tampa, Florida; Dr. Dan W. Elliott, professor emeritus of surgery at Wright State University, in Dayton, Ohio; Dr. E. Christopher Ellison, the Robert M. Zollinger professor and chairman of surgery at Ohio State University, in Columbus, Ohio; Dr. Timothy C. Fabian, professor and chairman of surgery at the University of Tennessee, in Memphis, Tennessee; and Mrs. Letitia Roberts, the widow of Dr. Stuart S. Roberts, the first recipient of the Zollinger Chair of Surgery at Ohio State, of Peoria, Illinois.