Oncologic outcomes after robot-assisted versus laparoscopic distal pancreatectomy: Analysis of the National Cancer Database

BACKGROUND

How the oncologic outcomes after robotic distal pancreatectomy (RDP) compare to those after laparoscopic distal pancreatectomy (LDP) remains unknown.

METHODS

Using the National Cancer Database (NCDB), we analyzed all patients undergoing LDP or RDP for resectable pancreatic adenocarcinoma over a 4-year period (2010-2013).

RESULTS

Of the 704 eligible patients, 605 (86%) underwent LDP and 99 (14%) underwent RDP. The median follow-up for patients was 25 months. There were no differences in the two groups with respect to sociodemographic, clinicopathologic, or treatment characteristics. On comparing LDP versus RDP, there was no difference in the margin-positive rate (15% vs 16%; P = 0.84); lymph nodes examined (12 vs 11; P = 0.67); overall survival (hazard ratio [HR], 1.1, 95% confidence intervals [CI], 0.7 to 1.7; 28 vs 25 months; P = 0.71); hospital stay (6 vs 5 days; P = 0.14); time to chemotherapy (50 vs 52 days; P = 0.65); 30-day readmission (9.4% vs 9.1%; P = 0.92); and mortality (1% vs 0%; P = 0.28). Patients undergoing LDP had a significantly higher conversion rate to open or minimally invasive pancreatic cancer resections compared with RDP (27% vs 10%; P < 0.001).

CONCLUSION

The early national experience with RDP demonstrates similar oncologic outcomes to LDP, with a significantly lower conversion rate.

A collaborative surgical approach to upper and lower abdominal cytoreductive surgery in ovarian cancer

BACKGROUND AND OBJECTIVES

Cytoreductive surgery with complete macroscopic resection in patients with ovarian cancer is associated with improved survival. Institutional reports of combined upper and lower abdominal cytoreductive surgery for more advanced disease have described multidisciplinary approaches. We sought to investigate outcomes in patients undergoing cytoreductive surgery in patients with upper and lower abdominal disease at our institution.

METHODS

Patients who underwent cytoreductive surgery for ovarian malignancies from 2008 to 2015 were retrospectively identified from an institutional database. Upper abdominal cytoreduction was defined anatomically as debulking of disease proximal to the ligament of Treitz. Perioperative outcomes were analyzed.

RESULTS

A total of 258 operations were performed, the majority for serous ovarian carcinoma (70%). The gynecologic oncologist was the primary surgeon and often assisted by either a surgical oncology fellow and/or attending. In operations with combined upper and lower abdominal cytoreduction, patients were more likely to have an American society of anesthesiologists physical status classification system (ASA) of 3, peritoneal implants, and liver/spleen metastases. Preoperative chemotherapy and optimal cytoreduction were similar between groups. Perioperative morbidity and mortality were not significantly different between groups.

CONCLUSIONS

A collaborative surgical approach to combined upper and lower abdominal cytoreductive surgery in patients with ovarian cancer should be performed, if needed, to achieve an optimal cytoreduction.

Orexin-1 receptors in the rostral ventromedial medulla are involved in the modulation of capsaicin evoked pulpal nociception and impairment of learning and memory

AIM

To investigate the role of rostral ventromedial medulla orexin-1 receptors in the modulation of orofacial nociception as well as nociception-induced learning and memory impairment in adult male rats.

METHODOLOGY

Pulpal nociception was induced by intradental application of capsaicin (100 μg) into the incisors of rats. Orexin-1 receptors agonist (orexin-A, 10, 25 and 50 pmol L^-1  rat^-1 ) and antagonist (SB-334867-A, 40 and 80 nmol L^-1  rat^-1 ) were microinjected into the rostral ventromedial medulla prior to capsaicin administration. Total time spent on nocifensive behaviour was recorded by direct visualization of freely moving rats whilst learning and memory were evaluated by the Morris water maze test. One-way analysis of variance and repeated-measures were used for the statistical analysis.

RESULTS

Capsaicin-treated rats had a significant increase of nocifensive behaviours (P < 0.001), as well as learning and memory impairment (P < 0.001). However, intraventromedial medulla prior micro-injection of orexin-A (50 pmol L^-1  rat^-1 ) significantly reduced the nociceptive behaviour (P < 0.001). This effect was blocked by pre-treatment with SB334867-A (80 nmol L^-1  rat^-1 ). Orexin-A (50 pmol L^-1  rat^-1 ) also inhibited nociception-induced learning and memory deficits. Moreover, administration of SB-334867-A (80 nmol L^-1  rat^-1 ) plus orexin-A (50 pmol L^-1  rat^-1 ) had no effect on learning and memory deficits induced by capsaicin.

CONCLUSIONS

The data suggest that rostral ventromedial medulla orexin-A receptors are involved in pulpal nociceptive modulation and improvement of learning and memory deficits induced by intradental application of capsaicin.

Propensity score-matched comparison of oncological outcomes between laparoscopic and open distal pancreatic resection

BACKGROUND

Selected studies have reported improved outcomes in laparoscopic compared with open distal pancreatic resection. Concerns regarding failure to achieve proper oncological resection and compromised long-term outcomes remain. This study investigated whether postoperative outcomes and long-term survival after laparoscopic distal pancreatectomy are comparable to those after an open procedure.

METHODS

This retrospective case-control study included patients who underwent distal pancreatectomy for resectable pancreatic adenocarcinoma between 2010 and 2013, identified from the National Cancer Database. Propensity score nearest-neighbour 1 : 1 matching was performed between patients undergoing laparoscopic or open distal pancreatectomy based on all relevant co-variables. The primary outcome was overall survival.

RESULTS

Of 1947 eligible patients, 605 (31·1 per cent) underwent laparoscopic distal pancreatectomy. After propensity score matching, two well balanced groups of 563 patients each were analysed. There was no difference in overall survival at 3 years after laparoscopic versus open distal pancreatectomy (41·6 versus 36·0 per cent; hazard ratio 0·93, 95 per cent c.i. 0·77 to 1·12; P = 0·457). The overall conversion rate was 27·3 per cent (165 of 605). Patients who underwent laparoscopic distal pancreatectomy had outcomes comparable to those of patients who had an open procedure with regard to median time to chemotherapy (50 versus 50 days; P = 0·342), median number of nodes examined (12 versus 12; P = 0·759); 30-day mortality (1·2 versus 0·9 per cent; P = 0·562); 90-day mortality (2·8 versus 3·7 per cent; P = 0·403), 30-day readmission rate (9·6 versus 9·2 per cent; P = 0·838) and positive margin rate (14·9 versus 18·5 per cent; P = 0·110). However, median duration of hospital stay was shorter in the laparoscopic group (6 versus 7 days; P < 0·001).

CONCLUSION

Laparoscopic distal pancreatectomy is an acceptable alternative to open distal pancreatectomy with no detriment to survival.

Association of Fluid Administration With Morbidity in Cytoreductive Surgery With Hyperthermic Intraperitoneal Chemotherapy

Importance

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal cancers can be associated with significant complications. Randomized trials have demonstrated increased morbidity with liberal fluid regimens in abdominal surgery.

Objective

To investigate the association of intraoperative fluid administration and morbidity in patients undergoing CRS/HIPEC.

Design, Setting, and Participants

A retrospective analysis of information from a prospectively collected institutional database was conducted at a National Cancer Institute-designated comprehensive cancer center. A total of 133 patients from April 15, 2009, to June 23, 2016, with primary or secondary peritoneal cancers were included.

Exposures

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy.

Main Outcomes and Measures

Morbidity associated with intraoperative fluid management calculated by the comprehensive complication index, which uses a formula combining all perioperative complications and their severities into a continuous variable from 0 to 100 in each patient.

Results

Of the 133 patients identified, 38% and 37% had diagnoses of metastatic appendiceal and colorectal cancers, respectively. Mean age was 54 (interquartile range [IQR], 47-64) years, and mean peritoneal cancer index was 13 (IQR, 7-18). Mitomycin and platinum-based chemotherapeutic agents were used in 96 (72.2%) and 37 (27.8%) of the patients, respectively. Mean intraoperative fluid (IOF) rate was 15.7 (IQR, 11.3-18.7) mL/kg/h. Mean comprehensive complication index (CCI) was 26.0 (IQR, 8.7-36.2). On multivariate analysis, age (coefficient, 0.32; 95% CI, 0.01-0.64; P = .04), IOF rate (coefficient, 0.97; 95% CI, 0.19-1.75; P = .02), and estimated blood loss (coefficient, 0.02; 95% CI, 0.01-0.03; P = .002) were independent predictors of increased CCI. In particular, patients who received greater than the mean IOF rate experienced a 43% increase in the CCI compared with patients who received less than the mean IOF rate (31.5 vs 22.0; P = .02).

Conclusions and Relevance

Intraoperative fluid administration is associated with a significant increase in perioperative morbidity in patients undergoing CRS/HIPEC. Fluid administration protocols that include standardized restrictive fluid rates can potentially help to mitigate morbidity in patients undergoing CRS/HIPEC.

The Comprehensive Complication Index: a New Measure of the Burden of Complications After Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Cytoreduction and hyperthermic intraperitoneal chemotherapy (HIPEC) are complex surgeries with multiple comorbidities. The Clavien-Dindo classification (CDC) is the most commonly used method to report surgical morbidity, but limits it to the highest-grade complication. The Comprehensive Complication Index (CCI) is a score ranging from 0 to 100, calculated using all 30-day complications and their treatment after abdominal surgery. The aim of this study is to assess the CCI's validity in the HIPEC patient population.

METHODS

A review of our institutional cytoreduction database from 2009 to 2015 was undertaken. Patient demographics, pathology, Peritoneal Carcinomatosis Index (PCI), complications and their treatments, and length of stay (LOS) were reviewed. The CCI was calculated for each patient. Linear regression was used to assess whether the CCI and CDC were predictors of LOS.

RESULTS

Of 157 patients reviewed, 110 (70.1%) underwent HIPEC. The majority were female (77, 66.9%), and the mean age was 53.7 years. Mean PCI was 13.2 [interquartile range (IQR) 7-18]. Median CDC was grade 2 (IQR 0-2), and only 9.8% had CDC of grade 4 or higher. Mean CCI was 21.4, while the median was 20.9 (IQR 0-30.8). Mean LOS was 16.2 days, while the median was 11 days (IQR 8-15 days). The CCI strongly correlated with LOS with coefficient of 0.46 [95% confidence interval (CI) 0.38-0.54, p = 0.000].

CONCLUSIONS

The CCI is an adequate tool to capture all complications and their overall burden in patients having undergone HIPEC. This study shows that the CCI can predict LOS and could be used to quantify and compare the burden of multiple complications.

Evolving Role of Hepatic Resection for Metastatic Urologic Malignancies

Liver resection for noncolorectal, nonneuroendocrine metastases remains controversial. Here, we evaluate a single institutional experience with hepatic resection for metastatic urologic malignancies. A single-institution review of patients who underwent hepatic resection for metastatic urologic tumors between the years of 2000 and 2013 was performed. Patient charts were analyzed for pathologic data and perioperative outcomes including short- and long-term morbidity, mortality, and overall and disease-free survival. Eleven patients were identified who underwent hepatic resection for metastatic urologic malignancy. The mean age was 63.5 years. All patients had an R0 resection. There were three major complications. Mean length of stay was 6.5 days and there was no 90-day mortality. Three patients have died of recurrent disease at an average of 11.2 months from resection to death. The remaining patients are still alive during a mean follow-up of 31.5 months. Five-year overall and disease-free survival was 50 and 21 months, respectively. Hepatic resection for metastatic urologic tumors is safe with low morbidity and mortality and durable long-term survival can be achieved. Liver resection for isolated hepatic disease should be considered for this rare metastatic disease to the liver.

Development and Validation of a Prognostic Score for Intrahepatic Cholangiocarcinoma

Importance

In patients with intrahepatic cholangiocarcinoma (ICC), the oncologic benefit of surgery and perioperative outcomes for large multifocal tumors or tumors with contiguous organ involvement remain to be defined.

Objectives

To develop and externally validate a simplified prognostic score for ICC and to determine perioperative outcomes for large multifocal ICCs or tumors with contiguous organ involvement.

Design, Setting, and Participants

This study of a contemporary cohort merged data from the California Cancer Registry (January 1, 2004, through December 31, 2011) and the Office of Statewide Health Planning and Development inpatient database. Clinicopathologic variables were compared between tumors that were intrahepatic, small (<7 cm), and solitary (ISS) and those that had extrahepatic extension and were large (≥7 cm) and multifocal (ELM). External validation of the prognostic model was performed using an independent data set from the National Cancer Institute's Surveillance, Epidemiology, and End Results database from January 1, 2004, through December 31, 2013.

Main Outcomes and Measures

Patient overall survival after hepatectomy.

Results

A total of 275 patients (123 men [44.7%] and 152 women [55.3%]; median [interquartile range] age, 65 [55-72] years) met the inclusion criteria. No significant differences in overall complication rate (ISS, 48 [34.5%]; ELM, 37 [27.2%]; P = .19) and mortality rate (ISS, 10 [7.2%]; ELM, 6 [4.4%]; P = .32) were found. A multivariate Cox proportional hazards model demonstrated that multifocality, extrahepatic extension, grade, node positivity, and age greater than 60 years are independently associated with worse overall survival. These variables were used to develop the MEGNA prognostic score. The prognostic separation/discrimination index was improved with the MEGNA prognostic score (0.21; 95% CI, 0.11-0.33) compared with the staging systems of the American Joint Committee on Cancer sixth (0.17; 95% CI, 0.09-0.29) and seventh (0.18; 95% CI, 0.08-0.30) editions.

Conclusions and Relevance

The MEGNA prognostic score allows more accurate and superior estimation of patient survival after hepatectomy compared with current staging systems.

Potentially preventable readmissions after complex cancer surgery: Analysis of the national readmissions dataset

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Background: Hospital readmissions following surgery are a focus of quality improvement efforts nationwide. Although some reflect appropriate care, others are potentially preventable readmissions (PPRs). We aim to describe the burden, timing, and factors associated with PPRs after complex cancer surgery. Methods: The National Readmissions Dataset (2013) was used to select patients undergoing a complex oncologic resection (defined as esophagectomy/gastrectomy, hepatectomy, pancreatectomy, colorectal resection, lung resection, and cystectomy). All Readmissions occurring within 30 days from discharge were analyzed. Causes for readmissions were categorized in eleven diagnostic groups and tabulated. ICD-9 primary diagnosis codes were reviewed to identify PPRs. Logistic regression analyses were used to identify demographic, clinical and hospital factors associated with PPRs. Results: We analyzed 60,970 patients with 92,260 admissions. A 30 day readmission occurred in 14% of patients, and was highest following cystectomy (25%) and lowest for lung resections (9%). Of all readmissions 82% were deemed to be PPRs. Half of PPRs occurred within the first 10 days of discharge. Infections, gastrointestinal complications and respiratory conditions accounted for 59% of PPRs. Other common causes included dehydration/electrolyte deficiencies (11%), exacerbation of comorbidity (9.2%), bleeding (5%), thromboembolism (3.5%), and wound complications (3.2%). Factors associated with an increased likelihood of PPRs include Medicaid compared with private insurance (OR 1.24, 95%CI 0.8-1.7), higher comorbid conditions (OR 1.44, 95%CI 1.32, 1.59), and discharge to a facility (OR 1.9, 95%CI 1.7-2.1). Patients with a prolonged hospital stay or a major complication during the index admission had a 34% (OR 1.34, 95%CI 1.3-1.4), and 64% (OR 1.64, 95%CI 1.5-1.7) higher likelihood of a PPR respectively. Conclusions: Most 30 day readmissions after complex cancer surgery are potentially preventable and occur within 10 days of discharge. We identify common causes of readmission and high risk populations to help physicians, administrators and policy makers develop strategies to decrease PPRs.

A propensity-matched analysis of laparoscopic versus open distal pancreatectomy for pancreatic adenocarcinoma

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Background: Laparoscopic-assisted distal pancreatectomy (LDP) has improved perioperative outcomes over open distal pancreatectomy (ODP). Concerns regarding failure to achieve proper oncologic resection and compromised survival remain. Methods: Using the National Cancer Database (NCDB), we analyzed patients undergoing distal pancreatectomy for resectable pancreatic adenocarcinoma over a four-year period (2010-2014). Propensity score nearest-neighbor 1:1 matching (PSM) was performed between LDP and ODP patients based on age, sex, race, insurance, hospital volume, comorbidities, T-stage, N-stage, grade, neoadjuvant therapy, adjuvant therapy. Primary outcome was overall survival. Results: Of the 1,947 eligible patients, 605 (31%) underwent LDP. After PSM two well-balanced groups of 544 patients each were analyzed. There was a trend towards improved overall survival (OS) in patients undergoing LDP as compared to ODP (HR: 0.83, 95% CI 0.68-1.0; Median OS 29 vs. 23 months, p = 0.06). Patients undergoing ODP had a higher margin positive rate compared to those undergoing LDP (21.1% vs. 14.9%, p-value = 0.007). Overall conversion rate was 27%. Patients undergoing ODP had comparable outcomes to LDP in regards to median time to chemotherapy (50 vs. 48 days, p-value = 0.96); median nodes examined (12 vs. 12, p-value = 0.61); 30-day mortality (1.6% vs. 1.1%, p-value = 0.43); 90-day mortality (3.5% vs. 2.4%, p-value = 0.28); 30-day readmission rate (8.6% vs. 9.4%, p-value = 0.67). However, the median length of stay was shorter in the LDP group (6 vs. 7 days, p = 0.0001). Conclusions: In the absence of randomized trials, this is the largest comparative study demonstrating LDP as an acceptable alternative ODP, associated with a lower margin positive rate and shorter length of stay, and with no detriment in long term survival.

Role of aggressive surgical debulking in older adults with gastrointestinal neuroendocrine tumors

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Background: Carcinoid and neuroendocrine tumors are often diagnosed in older adults. However, limited evidence currently exist regarding the role of aggressive surgical debulking of primary gastrointestinal-neuroendocrine tumors (low to medium grade-pancreas, small bowel, colorectal) (GI-NETs) in older adultsage > 70 years. Methods: Patients age 70 years or older with a diagnosis of GI-NETs were identified using the California Cancer Registry between the years 2000 to2012. Linkage to patient discharge records provided information including resection of primary site (RPS), resection of liver metastases (LR), and liver directed therapy (LDT). Treatment group effects on overall survival (OS) were compared by Cox proportional hazard models. Results: A total of 2,039 patients were identified. Among the 1,661 patients without metastases, 74% (n = 1,234) received RPS and demonstrated improved survival (HR 0.50, p < 0.001) compared to those without RPS. Of the 378 number of patients with liver metastases, LDT alone (n = 23) was not significantly associated with survival (HR 0.65, p = 0.082). Reduced risk was similar for RPS alone (n = 149; HR 0.44, p < 0.001) when paired with LDT (n = 17, HR 0.45, p = 0.007). RPS with LR, either with or without LDT, indicated the greatest impact in survival risk (n = 25; HR 0.14, p < 0.001). Conclusions: Surgical management of the primary tumor and liver metastases in older adults age > 70 years with GI-NETs demonstrated a significant survival benefit.Aggressive surgical debulking should be considered among older adultsage > 70 years. Future studies among older adults with GI-NETs are warranted to better identify patients most likely to benefit from aggressive surgical management.

Prognostic significance of chromogranin A in small pancreatic neuroendocrine tumors

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Background: Theincidence of non-functional pancreatic neuroendocrine tumors (PNETs) < 2 cm is rising. The biologic behavior of these tumors is variable and therefore their management remains controversial. We hypothesized that chromogranin A (CgA) levels are prognostic in these patients and may help guide management. Methods: Patients with PNETs measuring < 2 cm, without distant metastases were identified from the National Cancer Database (NCDB) over a ten-year period (2004-2014). Patients were categorized as CgA high (> 36.4 ng/ml) or CgA low (<36.4 ng/ml), and those lacking data on CgA levels were excluded from the study. Univariate and multivariate analyses were performed using Cox proportional hazards model. Results: Of the 445 eligible patients, 149 (33.5%) were CgA Low and 296 (66.5%) were CgA High. Median CgA level was 71 (Inter-quartile range, IQR 24-294) ng/ml. On multivariate analysis, CgA levels independently predicted overall survival after controlling for tumor size, grade, clinical nodal status and academic status of the facility (p = 0.001). At a median follow up of 26.5 months there were no deaths in the CgA Low group whereas 8% of the patients in CgA High group had died (p = 0.0068). Only CgA High patients benefited from surgical resection (HR 0.31, 95% CI 0.11-0.86, p = 0.025). Conclusions: Serum CgA levels can be incorporated in surgical decision making for patients with small PNETs. Patients with a high CgA should be strongly considered for resection.

Adjuvant chemoradiation for node-positive pancreatic adenocarcinoma: A propensity-matched analysis

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Background: American Society of Clinical Oncology guidelines recommend adjuvant chemoradiation (ACR) for margin-positive(R1) and/or node-positive (N+) pancreatic cancers. However, randomized trials and meta-analyses have have not shown superiority of ACR over AC. Methods: National Cancer Database (NCDB) was used to analyze patients with N+ and/or R1 pancreatic adenocarcinoma who underwent ACR or AC over a ten-year period (2004-2014). Patients who received neoadjuvant radiation, no adjuvant treatment or adjuvant radiation alone were excluded. Propensity score nearest-neighbor 1:1 matching (PSM) was performed between ACR and AC groups based on age, sex, race, insurance, comorbidities, T-stage, nodal status, margin status, grade, and neoadjuvant chemotherapy. Primary outcome was overall survival (OS). Results: A total of 9,732 patients were eligible. After PSM two well-balanced groups of 4000 patients each were analyzed. ACR resulted in superior OS in patients with N+ and/or R1 disease as compared to AC alone (HR: 0.83, 95% CI 0.78-0.87; Median OS 22 vs. 19 months, p<0.001). Subset analyses demonstrated overall survival benefit of ACR compared to AC in N+, margin-negative patients (HR: 0.82, 95% CI 0.77-0.88; Median OS 24 vs. 20 months, p<0.001), as well as N+, R1 patients (HR: 0.77, 95% CI 0.68-0.87; Median OS 17 vs. 15 months, p<0.001); but no benefit in node-negative, R1 patients (HR: 1.12, 95% CI 0.84-1.48; Median OS 18 vs. 22 months, p = 0.43). Conclusions: This is the largest study to date that shows superiority of ACR over AC in N+ patients irrespective of margin status. The study failed to show a survival benefit in R1, node-negative patients.

Minimally invasive surgery to improve time to chemotherapy in colon cancer: Compliance to the American College of Surgeons Commission on Cancer quality metrics

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Background: One of the American College of Surgeons Commission on Cancer (ACS CoC) quality measures in colon cancer is receipt of chemotherapy (CT) in Stage III disease within 120 days of diagnosis. Minimally invasive surgery (MIS) has been associated with faster recovery times. The aim of this study is to assess whether MIS improves compliance to this metric. Methods: Stage III colon cancer patients 80 years old and younger from 2010 to 2012 were identified in the National Cancer Database. Demographic, tumor and treatment characteristics were evaluated including receipt of CT and surgical approach. Uni- and multi-variate logistic regression was used to assess factors associated with CT compliance. Results: Of the 19,963 patients identified, 14,901(74.6%) were compliant while 5,062 (25.3%) were not. Of the patients who were non-compliant, 956 (4.8%) received CT after 120 days. Surgical approach was significantly different between CT compliant and non-compliant groups (MIS 28% vs 32%,p < 0.000). Uni- and multi-variate analyses identified MIS as a significant factor associated with improved compliance to CT with an OR of 1.31 (95%CI 1.22-1.41). Other factors associated with CT compliance were nodal and tumor stage and treatment in an academic program. Non-compliance was associated with age 50-64 (OR 0.76; 95%CI 0.68-0.86), age 65-79 (OR 0.49; 95%CI 0.43-0.56) and increased co-morbidities (OR 0.60; 95%CI 0.53-0.67). Lack of insurance (OR 0.69; 95%CI 0.58-0.81) or Medicaid (OR 0.54; 95%CI 0.47-0.62) and Medicare (OR 0.69; 95%CI 0.63-0.77) as well as distance to hospital of more than 44 miles were also associated with non-compliance to CT (OR 0.86; 95%CI 0.76-0.97). Conclusions: This is the first study to demonstrate that MIS for Stage III colon cancer improves compliance to receipt of CT within the 120 days. Given the potential survival benefits as a result of adherence to ACS CoC cancer care quality metrics, MIS may benefit patients not only in faster return to recovery but also in improved cancer outcomes.

Effect of Gastric Bypass on Bone Mineral Density, Parathyroid Hormone and Vitamin D: 5 Years Follow-up

BACKGROUND

The aim of the present study was to see if there are longitudinal changes in bone mineral density (BMD), vitamin D or parathyroid hormone (PTH) in females 5 years after Laparoscopic Roux-en-Y Gastric Bypass (LRYGB).

METHODS

Thirty-two women with mean age 41.6 ± 9.3 years and mean body mass index (BMI) 44.5 ± 4.6 kg/m(2) were included. Preoperatively, 2 and 5 years postoperatively, BMD, weight, height, S-calcium, S-albumin, S-creatinine, S-25(OH)-vitamin D and fP-PTH were measured.

RESULTS

The mean decrease in BMI between baseline and 5 years after surgery was 29.4%. BMD of the spine and femur measured as z- and t-scores, showed a linear, statistically significant declining trend over the years. The fall in BMD of the spine and femoral neck between baseline and 5 years after surgery was 19 and 25%, respectively. The mean fP-PTH showed a significant increase over the study period (20.2 μg/L increase, 95% CI:-31.99 to -8.41). S-calcium, both free and corrected for albumin, showed a decrease between baseline and 5 years after surgery. Eight patients developed osteopenia and one osteoporosis after a 5-year follow-up.

CONCLUSION

LRYGB is an efficient method for sustained long-term body weight loss. There is, however, a concomitant decrease in BMD and S-calcium, and an increase in fP-PTH.

Prognostic significance of lymph node yield in ypN0 rectal cancer

BACKGROUND

Neoadjuvant radiation therapy for locally advanced rectal adenocarcinoma decreases lymph node yield. This study investigated the association between survival and number of lymph nodes evaluated in patients with pathologically negative nodes after neoadjuvant therapy.

METHODS

Patients with locally advanced rectal adenocarcinoma who underwent neoadjuvant therapy and had pathologically negative lymph nodes were included from the Surveillance, Epidemiology, and End Results (SEER) database over a 7-year interval (January 2004 to December 2010). Systematic dichotomization for optimal cut-off point identification was performed using statistical modelling.

RESULTS

A total of 3995 patients met the inclusion criteria. The majority had T3 (66·7 per cent) and moderately differentiated (71·5 per cent) tumours. The median number of lymph nodes retrieved was 12 (i.q.r. 7-16). An optimal cut-off of nine lymph nodes was identified. Increasing age (P < 0·001), increasing T category (T4 versus T1, P < 0·001; T3 versus T1, P = 0·010), response to neoadjuvant therapy (P < 0·001) and number of nodes evaluated (P < 0·001) were significant factors for overall survival in univariable analysis. After adjustment in the multivariable model, the group with nine or more nodes examined had significantly better overall survival (hazard ratio (HR) 0·76, 95 per cent c.i. 0·65 to 0·88, P < 0·001; 5-year survival 83·2 versus 78·0 per cent) and cancer-specific survival (HR 0·76, 0·64 to 0·92, P = 0·004; 5-year survival 87·9 versus 85·1 per cent) than the group with one to eight nodes examined.

CONCLUSION

Overall and cancer-specific survival were worse where fewer than nine lymph nodes were identified after neoadjuvant therapy for locally advanced rectal cancer.

Intrahepatic cholangiocarcinoma: Ambitious operations and outcomes

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Background: Data from specialized institutions suggests that resection for large ( > 7cm) and mutifocal intrahepatic cholangiocarcinoma (ICC) is safe and feasible. We aim to study this hypothesis using a population-based dataset. Methods: This is a study of a contemporary cohort from California Cancer Registry database (2004-2011) that was merged with Office of Statewide Health Planning and Development inpatient database. All patients with ICC that underwent resection or ablation were included. Tumors were classified into two groups; intrahepatic, small ( < 7cm) & solitary (ISS) vs. extrahepatic extension, large or multifocal (ELM). Mortality was recorded at 90 days. Overall survival (OS) analysis was performed using the Kaplan-Meier and Cox-proportional hazard model. Results: Of the total 275 patients that met the inclusion criteria, 55% were female, 52% were white and median age was 65 years (IQR 55-72). Majority of patients had > 3 segment resection 59% (Ablation 10%, 1-3 segments 30%). Portal lymphadenectomy was performed in 45% of patients. Vascular Invasion was found in 22% of patients, 14% were bilobar and 20% were node positive. Median follow up was 23 months (IQR 13-40). Number of ISS tumors (139, 50.5%) and ELM tumors (136, 49.5%) was similar. The two groups were comparable in regards to age, sex, race, comorbidities, extent of surgery, portal lymphadenectomy, node positivity. ELM tumors were more likely to have vessel invasion (27% vs. 17%, p = 0.048) and be bilobar (26% vs. 2%, p < 0.001). There was no significant difference in overall complication rate (ISS 34%, ELM 27%, p = 0.19) and mortality rate (both groups < 1%, p = 0.32). A multivariate Cox-proportional hazard model demonstrated that age > 60 years, > 1 comorbidity, high grade tumors, ELM tumors (HR 1.63: 95%CI 1.11-2.40; p = 0.013) and LN positivity (HR 2.30: 95%CI 1.49-3.54; p < 0.001) are independently associated with worse OS. Conclusions: Surgical resection of tumors > 7cm, multifocal lesions involving contiguous extrahepatic organs is safe with acceptable morbidity and mortality. Age > 60 years, grade, comorbidity, ELM tumors and LN positivity are independent predictors of worse OS.

Prognostic significance of lymph node sampling in node-negative appendiceal carcinoids

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Background: Surgical resection is the primary therapy for local and locally advanced carcinoid tumors of the appendix. The extent of surgery is largely dictated by the size of the tumor. Tumors >2 cm require a right hemicolectomy with associated mesenteric lymphadenectomy. What constitutes an adequate mesenteric lymphadenectomy is not known. Methods: This is a study of a contemporary cohort from NCI’s SEER database (Jan, 2004- Nov, 2012). Patients with non-metastatic appendiceal carcinoid tumors were included. Surgical extent was defined as limited (appendectomy or illeocecectomy) or extended (hemicolectomy). Primary outcome was overall survival (OS). Survival analysis was performed using the Kaplan-Meier and Cox-proportional hazards model. Results: Of the total 1,104 patients that met the inclusion criteria, 52% were female, 88% were white and majority were middle aged (40-60y) 45%. Majority of the tumors were <2 cm (49.3%) and lymph node(LN) negative 85%. Median LN retrieved were 10 (IQR 0-17). Median follow-up was 32 months (IQR 10-61). A multivariate Cox-proportional hazard model demonstrated that increasing age, tumor size > 3cm, tumor spread to contiguous organs, LN positivity and LN count <11 (HR 1.78: 95%CI 1.17-2.69; p=0.006) are associated with worse OS. Five-year overall survival increased with the number of LN retrieved (LN 1-10, 81.4%; LN >10, 85.9%, p=0.035). Stratified analysis by LN status demonstrated that LN count <11 was an independent predictor of worse OS in node negative patients (HR 2.10: 95%CI 1.25-3.53; p=0.005) but not node positive patients (p=0.65). Subset analysis by tumors size demonstrated that prognostic value of LN count <11 was only significant for tumors greater than 3 cm (HR 2.32: 95%CI 1.15-2.03; p=0.018). Conclusions: This is the largest study to date that looks at prognostic significance of LN count for appendiceal carcinoids. The number of LNs evaluated is an independent prognostic factor in pathologic node-negative, appendiceal carcinoid tumors measuring greater than 3 cm. This data supports performing a formal lymphadenectomy (>10 LN) even if no mesenteric disease is visible for adequate staging.

Health-Related Quality-of-Life (HRQoL) on an Average of 12 Years After Gastric Bypass Surgery

BACKGROUND

It is evident that morbidly obese patients have a low health-related quality-of-life (HRQoL), and this low HRQoL has become a common reason for them to seek bariatric surgery. Several HRQoL studies demonstrate a dramatic postoperative improvement, but most of these have had a short follow-up period.

MATERIAL AND METHODS

An observational, cross-sectional study for HRQoL was conducted to study 486 patients (average age of 50.7 ± 10.0 years, with 84 % of them being female) operated with gastric bypass (GBP) in the period 1993 to 2003 at the University Hospitals of Örebro and Uppsala. Mean follow-up after gastric bypass was 11.5 ± 2.7 years (range 7-17). Two HRQoL instruments were used, SF-36 and the Obesity-related Problems scale (OP). The study group was compared with two control groups, both matched for age and gender, one from the general population and one containing morbidly obese patients evaluated and awaiting bariatric surgery.

RESULTS

The study group scored better in the SF-36 domains (all four physical domains and the vitality subscore) and OP scale compared to obese controls, but their HRQoL scores were lower than those of the general population. HRQoL was better among younger patients and in the following subgroups: men, patients with satisfactory weight loss, satisfied with the procedure, free from co-morbidities and gastrointestinal symptoms, employment, good oral status and those not hospitalised or regularly followed up for non-bariatric reasons.

CONCLUSION

Long-term follow-up after GBP for morbid obesity showed better scores in most aspects of HRQoL compared to obese controls but did not achieve the levels of the general population. Patients with better medical outcome after gastric bypass operation had better HRQoL.

Longitudinal assessment of physical activity in women undergoing Roux-en-Y gastric bypass

BACKGROUND

Patients undergoing bariatric surgery do not seem to increase objectively measured physical activity (PA) after surgery, despite substantial weight loss. The aims of the present study were (i) to objectively characterize 3 months pre-surgery to 9 months postsurgery PA and sedentary behavior changes in women undergoing Roux-en-Y gastric bypass (RYGB) using tri-axial accelerometers and (ii) to examine associations between pre-surgery versus postsurgery PA and sedentary behavior with anthropometric measures taken in home environment.

METHODS

Fifty-six women, with an average pre-surgery body mass index (BMI) of 37.6 (SD 2.6) and of age 39.5 years (SD 5.7), were recruited at five Swedish hospitals. PA was measured for 1 week by the Actigraph GT3X+ accelerometer, and anthropometric measures were taken at home visits 3 months pre-surgery and 9 months postsurgery, thus limiting seasonal effects.

RESULTS

Average BMI loss, 9 months postsurgery, was 11.7 (SD 2.7) BMI units. There were no significant pre- to postsurgery differences in PA or sedentary behavior. However, pre-surgery PA showed negative association with PA change and positive association with postsurgery PA. Adjustments for pre-surgery BMI had no impact on these associations.

CONCLUSIONS

No significant differences were observed in objectively measured changes in PA or time spent sedentary from 3 months pre-surgery to 9 months postsurgery among women undergoing RYGB. However, women with higher pre-surgery PA decreased their PA postsurgery while women with lower pre-surgery PA increased their PA.

A New Imaging Platform for Visualizing Biological Effects of Non-Invasive Radiofrequency Electric-Field Cancer Hyperthermia

Herein, we present a novel imaging platform to study the biological effects of non-invasive radiofrequency (RF) electric field cancer hyperthermia. This system allows for real-time in vivo intravital microscopy (IVM) imaging of radiofrequency-induced biological alterations such as changes in vessel structure and drug perfusion. Our results indicate that the IVM system is able to handle exposure to high-power electric-fields without inducing significant hardware damage or imaging artifacts. Furthermore, short durations of low-power (< 200 W) radiofrequency exposure increased transport and perfusion of fluorescent tracers into the tumors at temperatures below 41°C. Vessel deformations and blood coagulation were seen for tumor temperatures around 44°C. These results highlight the use of our integrated IVM-RF imaging platform as a powerful new tool to visualize the dynamics and interplay between radiofrequency energy and biological tissues, organs, and tumors.

Hyperthermia inhibits recombination repair of gemcitabine-stalled replication forks

BACKGROUND

Gemcitabine is a potent nucleoside analogue against solid tumors, but development of drug resistance is a substantial problem. Removal of gemcitabine incorporated into DNA by repair mechanisms may contribute to resistance in chemo-refractory solid tumors. Human hepatocellular carcinoma (HCC) is usually very chemoresistant to gemcitabine.

METHODS

We treated HCC in vitro and in vivo (orthotopic murine model with human Hep3B or HepG2 xenografts, 7-10 CB17SCID mice per group) with gemcitabine. The role of homologous recombination repair proteins in repairing stalled replication forks was evaluated with hyperthermia exposure and cell-cycle analysis. The Student t-test was used for two-sample comparisons. Multiple group data were analyzed using one-way analysis of variance. All statistical tests were two-sided.

RESULTS

We demonstrated that Mre11-mediated homologous recombination repair of gemcitabine-stalled replication forks is crucial to survival of HCC cells. Furthermore, we demonstrated inhibition of Mre11 by an exonuclease inhibitor or concomitant hyperthermia. In orthotopic murine models of chemoresistant HCC, the Hep3B tumor mass with radiofrequency plus gemcitabine treatment (mean ± SD, 180±91mg) was statistically significantly smaller compared with gemcitabine alone (661±419mg, P = .0063).

CONCLUSIONS

This study provides mechanistic understanding of homologous recombination inhibiting-strategies, such as noninvasive radiofrequency field-induced hyperthermia, to overcome resistance to gemcitabine in refractory human solid tumors.

Gold nanoparticles and radiofrequency in experimental models for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most lethal and chemo-refractory cancers, clearly, alternative treatment strategies are needed. We utilized 10nm gold nanoparticles as a scaffold to synthesize nanoconjugates bearing a targeting antibody (cetuximab, C225) and gemcitabine. Loading efficiency of gemcitabine on the gold nanoconjugates was 30%. Targeted gold nanoconjugates in combination with RF were selectively cytotoxic to EGFR expressing Hep3B and SNU449 cells when compared to isotype particles with/without RF (P<0.05). In animal experiments, targeted gold nanoconjugates halted the growth of subcutaneous Hep3B xenografts in combination with RF exposure (P<0.05). These xenografts also demonstrated increased apoptosis, necrosis and decreased proliferation compared to controls. Normal tissues were unharmed. We have demonstrated that non-invasive RF-induced hyperthermia when combined with targeted delivery of gemcitabine is more effective and safe at dosages ~275-fold lower than the current clinically-delivered systemic dose of gemcitabine.

FROM THE CLINICAL EDITOR

In a model of hepatocellular carcinoma, the authors demonstrate that non-invasive RF-induced hyperthermia applied with cetuximab targeted delivery of Au NP-gemcitabine conjugate is more effective and safe at dosages ~ 275-fold lower than the current clinically-used systemic dose of gemcitabine.

Morbidity and mortality in 1,174 patients undergoing hepatic parenchymal transection using a stapler device

BACKGROUND

Transection of liver parenchyma using staplers is now commonly performed. Large studies are needed to assess the usefulness of the technique as well as perioperative outcomes.

METHODS

This is a retrospective study of a prospectively maintained database. A total of 1,174 patients undergoing liver resections in routine surgical practice, using a stapler device at MD Anderson Cancer Center between January 1, 1994 and November 10, 2011 were evaluated.

RESULTS

There were 900 major resections (3 segments or more) (77 %) and 274 minor resections (<3 segments or wedge resections) (23 %). A vast majority, 1,133 (96.5 %), were indicated for an underlying malignancy (24 % primary liver or gall bladder and 72.5 % metastatic) compared with benign disease, 41 (3.5 %), with the most common indication being metastatic colorectal cancer 584 (49.7 %). Of the total 1,174 patients 128 (10.9 %) had a prior liver resection. Median OR time and blood loss was 206 min and 300 mL, respectively, with 11 % of patients requiring transfusion in the perioperative or postoperative period. Overall morbidity and mortality rate was 14 and 3.2 %, respectively, with a median hospital stay of 7 days (interquartile range [IQR], 4 days). Multivariate logistic regression demonstrated blood loss and extent of liver resection to be independent predictors of adverse outcome. A total of 13 instances (1.1 %) of misfired staplers were noted and were associated with higher blood loss (p < 0.001) and mortality (15 vs. 3.1 %, p = 0.013).

CONCLUSIONS

Use of stapler device for hepatic resection is safe and effective, but rare instances of a misfired stapler device are associated with an adverse outcome.

Morbidity and mortality in 1,174 patients undergoing hepatic parenchymal transection using a stapler device

BACKGROUND

Transection of liver parenchyma using staplers is now commonly performed. Large studies are needed to assess the usefulness of the technique as well as perioperative outcomes.

METHODS

This is a retrospective study of a prospectively maintained database. A total of 1,174 patients undergoing liver resections in routine surgical practice, using a stapler device at MD Anderson Cancer Center between January 1, 1994 and November 10, 2011 were evaluated.

RESULTS

There were 900 major resections (3 segments or more) (77 %) and 274 minor resections (<3 segments or wedge resections) (23 %). A vast majority, 1,133 (96.5 %), were indicated for an underlying malignancy (24 % primary liver or gall bladder and 72.5 % metastatic) compared with benign disease, 41 (3.5 %), with the most common indication being metastatic colorectal cancer 584 (49.7 %). Of the total 1,174 patients 128 (10.9 %) had a prior liver resection. Median OR time and blood loss was 206 min and 300 mL, respectively, with 11 % of patients requiring transfusion in the perioperative or postoperative period. Overall morbidity and mortality rate was 14 and 3.2 %, respectively, with a median hospital stay of 7 days (interquartile range [IQR], 4 days). Multivariate logistic regression demonstrated blood loss and extent of liver resection to be independent predictors of adverse outcome. A total of 13 instances (1.1 %) of misfired staplers were noted and were associated with higher blood loss (p < 0.001) and mortality (15 vs. 3.1 %, p = 0.013).

CONCLUSIONS

Use of stapler device for hepatic resection is safe and effective, but rare instances of a misfired stapler device are associated with an adverse outcome.

Protocols for assessing radiofrequency interactions with gold nanoparticles and biological systems for non-invasive hyperthermia cancer therapy

Cancer therapies which are less toxic and invasive than their existing counterparts are highly desirable. The use of RF electric-fields that penetrate deep into the body, causing minimal toxicity, are currently being studied as a viable means of non-invasive cancer therapy. It is envisioned that the interactions of RF energy with internalized nanoparticles (NPs) can liberate heat which can then cause overheating (hyperthermia) of the cell, ultimately ending in cell necrosis. In the case of non-biological systems, we present detailed protocols relating to quantifying the heat liberated by highly-concentrated NP colloids. For biological systems, in the case of in vitro experiments, we describe the techniques and conditions which must be adhered to in order to effectively expose cancer cells to RF energy without bulk media heating artifacts significantly obscuring the data. Finally, we give a detailed methodology for in vivo mouse models with ectopic hepatic cancer tumors.

Tumor selective hyperthermia induced by short-wave capacitively-coupled RF electric-fields

There is a renewed interest in developing high-intensity short wave capacitively-coupled radiofrequency (RF) electric-fields for nanoparticle-mediated tumor-targeted hyperthermia. However, the direct thermal effects of such high-intensity electric-fields (13.56 MHZ, 600 W) on normal and tumor tissues are not completely understood. In this study, we investigate the heating behavior and dielectric properties of normal mouse tissues and orthotopically-implanted human hepatocellular and pancreatic carcinoma xenografts. We note tumor-selective hyperthermia (relative to normal mouse tissues) in implanted xenografts that can be explained on the basis of differential dielectric properties. Furthermore, we demonstrate that repeated RF exposure of tumor-bearing mice can result in significant anti-tumor effects compared to control groups without detectable harm to normal mouse tissues.

Cytotoxicity and variant cellular internalization behavior of water-soluble sulfonated nanographene sheets in liver cancer cells

Highly exfoliated sulfonated graphene sheets (SGSs), an alternative to graphene oxide and graphene derivatives, were synthesized, characterized, and applied to liver cancer cells in vitro. Cytotoxicity profiles were obtained using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, WST-1[2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, and lactate dehydrogenase release colorimetric assays. These particles were found to be non-toxic across the concentration range of 0.1 to 10 μg/ml. Internalization of SGSs was also studied by means of optical and electron microscopy. Although not conclusive, high-resolution transmission and scanning electron microscopy revealed variant internalization behaviors where some of the SGS became folded and compartmentalized into tight bundles within cellular organelles. The ability for liver cancer cells to internalize, fold, and compartmentalize graphene structures is a phenomenon not previously documented for graphene cell biology and should be further investigated.

Remotely triggered cisplatin release from carbon nanocapsules by radiofrequency fields

The efficacy of nanoparticle-mediated drug delivery is limited by its peri-vascular sequestration, thus necessitating a strategy to trigger drug release from such intra-tumoral nanocarrier-drug depots. In our efforts to explore remotely-activated nanocarriers, we have developed carbon nanocapsules comprised of an ultra-short carbon nanotube shell (US-tubes) loaded with cisplatin (CDDP@US-tubes) and covered with a Pluronic surfactant wrapping to minimize passive release. We demonstrate here that non-invasive radiofrequency (RF) field activation of the CDDP@US-tubes produces heat that causes Pluronic disruption which triggers cisplatin release in an RF-dependent manner. Furthermore, release-dependent cytotoxicity is demonstrated in human hepatocellular carcinoma cell lines.

Citrate-capped gold nanoparticle electrophoretic heat production in response to a time-varying radiofrequency electric-field

The evaluation of heat production from gold nanoparticles (AuNPs) irradiated with radiofrequency (RF) energy has been problematic due to Joule heating of their background ionic buffer suspensions. Insights into the physical heating mechanism of nanomaterials under RF excitations must be obtained if they are to have applications in fields such as nanoparticle-targeted hyperthermia for cancer therapy. By developing a purification protocol which allows for highly-stable and concentrated solutions of citrate-capped AuNPs to be suspended in high-resistivity water, we show herein, for the first time, that heat production is only evident for AuNPs of diameters ≤ 10 nm, indicating a unique size-dependent heating behavior not previously observed. Heat production has also shown to be linearly dependent on both AuNP concentration and total surface area, and severely attenuated upon AuNP aggregation. These relationships have been further validated using permittivity analysis across a frequency range of 10 MHz to 3 GHz, as well as static conductivity measurements. Theoretical evaluations suggest that the heating mechanism can be modeled by the electrophoretic oscillation of charged AuNPs across finite length scales in response to a time-varying electric field. It is anticipated these results will assist future development of nanoparticle-assisted heat production by RF fields for applications such as targeted cancer hyperthermia.

Stability of antibody-conjugated gold nanoparticles in the endolysosomal nanoenvironment: implications for noninvasive radiofrequency-based cancer therapy

The use of noninvasive radiofrequency (RF) electric fields as an energy source for thermal activation of nanoparticles within cancer cells could be a valuable addition to the emerging field of nano-mediated cancer therapies. Based on investigations of cell death through hyperthermia, and offering the ability for total-body penetration by RF fields, this technique is thought to complement and possibly outperform existing nano-heat treatments that utilize alternative heat production via optical or magnetic stimuli. However, it remains a challenge to understand fully the complex RF-nanoparticle-intracellular interactions before full system optimization can be engineered. Herein we have shown that liver cancer cells can selectively internalize antibody-conjugated gold nanoparticles (AuNPs) through receptor-mediated endocytosis, with the nanoparticles predominantly accumulating and aggregating within cytoplasmic endolysosomes. After exposure to an external RF field, nonaggregated AuNPs absorbed and dissipated energy as heat, causing thermal damage to the targeted cancer cells. We also observed that RF absorption and heat dissipation is dependent on solubility of AuNPs in the colloid, which is pH dependent. Furthermore, by modulating endolysosomal pH it is possible to prevent intracellular AuNP aggregation and enhance thermal cytotoxicity in hepatocellular cancer cells.

FROM THE CLINICAL EDITOR

Gold nanoparticles absorb energy from RF fields and can exert hyperthermic effects leading to cell death. Combining this known effect with antibody-based targeting of the nanoparticles, selective cancer specific hyperthermia induced cell death therapies can be designed, as demonstrated in this article.

Luciferase-based protein denaturation assay for quantification of radiofrequency field-induced targeted hyperthermia: developing an intracellular thermometer

BACKGROUND

Several studies have reported targeted hyperthermia at the cellular level using remote activation of nanoparticles by radiofrequency waves. To date, methods to quantify intracellular thermal dose have not been reported. In this report we study the relationship between radio wave exposure and luciferase denaturation with and without intracellular nanoparticles. The findings are used to devise a strategy to quantify targeted thermal dose in a primary human liver cancer cell line.

METHODS

Water bath or non-invasive external Kanzius RF generator (600 W, 13.56 MHz) was used for hyperthermia exposures. Luciferase activity was measured using a bioluminescence assay and viability was assessed using Annexin V-FITC and propidium iodide staining. Heat shock proteins were analysed using western blot analysis.

RESULTS

Duration-dependent luciferase denaturation was observed in SNU449 cells exposed to RF field that preceded measurable loss in viability. Loss of luciferase activity was higher in cetuximab-conjugated gold nanoparticle (C225-AuNP) treated cells. Using a standard curve from water bath experiments, the intracellular thermal dose was calculated. Cells treated with C225-AuNP accumulated 6.07 times higher intracellular thermal dose than the untreated controls over initial 4 min of RF exposure.

CONCLUSION

Cancer cells when exposed to an external RF field exhibit dose-dependent protein denaturation. Luciferase denaturation assay can be used to quantify thermal dose delivered after RF exposures to cancer cells with and without nanoparticles.

Internalization of C60 fullerenes into cancer cells with accumulation in the nucleus via the nuclear pore complex

A highly water-soluble, non-ionic, and non-cytotoxic fullerene malonodiserinolamide-derivatized fullerene C(60) (C(60)-ser) is under investigation as a potential nanovector to deliver biologic and cancer drugs across biological barriers. Using laser-scanning confocal microscopy and flow cytometry, we find that PF-633 fluorophore conjugated C(60)-ser nanoparticles (C(60)-serPF) are internalized within living cancer cells in association with serum proteins through multiple energy-dependent pathways, and escape endocytotic vesicles to eventually localize and accumulate in the nucleus of the cells through the nuclear pore complex. Furthermore, in a mouse model of liver cancer, the C(60)-serPF conjugate is detected in most tissues, permeating through the altered vasculature of the tumor and the tightly-regulated blood brain barrier while evading the reticulo-endothelial system.

Organ donation after traumatic cardiopulmonary arrest

BACKGROUND

The gap between demand of transplantable organs and their supply continues to widen. Trauma patients constitute a significant proportion of organ donors. The incidence of organ donation after traumatic cardiopulmonary arrest (TCPA), however, is not clear. The goals of this study were to determine the success rate of organ donation in patients undergoing cardiopulmonary resuscitation (CPR) after trauma and to determine if there are variables that may predict successful organ donation.

METHODS

All trauma patients who sustained TCPA from April 2007 to March 2010 were reviewed. We identified all patients who required CPR in the field or the trauma center. Patients were classified as donors if the heart, lung, kidney, small bowel, pancreas, or liver was harvested. Primary outcome was organ donation after CPR.

RESULTS

A total of 252 patients required CPR for TCPA in the field or in the trauma center. There were 39 (15.5%) survivors and 213 (84.5%) fatalities. Only 19 of 213 (8.9%) patients who died after TCPA became organ donors. A total of 26 organs were harvested including 15 kidneys, 6 livers, 4 hearts, and 1 pancreas. Of those who failed to donate organs, 64.7% had a cardiac arrest after the donor network had been contacted but before their arrival.

CONCLUSIONS

Survival rate after TCPA is low but organ donation is an important secondary outcome. Patients with predominant head injuries, without thoracic and minimal extremity injuries, should be identified as having a higher chance of going on to organ donation. The greatest barrier to organ donation in TCPA patients is cardiac arrest before donor network arrival.

Non-invasive radiofrequency-induced targeted hyperthermia for the treatment of hepatocellular carcinoma

Targeted biological therapies for hepatocellular cancer have shown minimal improvements in median survival. Multiple pathways to oncogenesis leading to rapid development of resistance to such therapies is a concern. Non-invasive radiofrequency field-induced targeted hyperthermia using nanoparticles is a radical departure from conventional modalities. In this paper we underscore the need for innovative strategies for the treatment of hepatocellular cancer, describe the central paradigm of targeted hyperthermia using non-invasive electromagnetic energy, review the process of characterization and modification of nanoparticles for the task, and summarize data from cell-based and animal-based models of hepatocellular cancer treated with non-invasive RF energy. Finally, future strategies and challenges in bringing this modality from bench to clinic are discussed.

Comparative study of subcutaneous tissue responses to a novel root-end filling material and white and grey mineral trioxide aggregate

AIM

To compare the subcutaneous tissue response to grey mineral trioxide aggregate (GMTA), white mineral trioxide aggregate (WMTA) and a new experimental cement (calcium enriched cement, CEM).

METHODOLOGY

Thirty-six Wistar male albino rats each received three implants, containing one of the tested materials, and an empty tube as a control. Seven, 30 and 60 days after implantation, the animals were sacrificed. After histological preparation and H&E staining, the specimens were evaluated for capsule thickness, necrosis, and for the type, the severity, and the extent of inflammation. Kruskal Wallis and Chi-square tests were used for data analysis.

RESULTS

After 1 week, CEM produced no necrosis compared to both types of WMTA and GMTA (P = 0.007). After 30 days, GMTA specimens had significantly less inflammation compared with WMTA and CEM (P = 0.011). After 60 days, less inflammation was associated with CEM specimens (P = 0.0001) compared to the other materials. Dystrophic calcifications in the connective tissue adjacent to all experimental material were detected.

CONCLUSION

Histological observation illustrated that all materials were well tolerated by the subcutaneous tissues.

Effects of different respiratory maneuvers on esophageal sphincters in obese patients before and during anesthesia

BACKGROUND

Data on esophageal sphincters in obese individuals during anesthesia are sparse. The aim of the present study was to evaluate the effects of different respiratory maneuvers on the pressures in the esophagus and esophageal sphincters before and during anesthesia in obese patients.

METHODS

Seventeen patients, aged 28-68 years, with a BMI ≥ 35 kg/m², who were undergoing a laparoscopic gastric by-pass surgery, were studied, and pressures from the hypopharynx to the stomach were recorded using high-resolution solid-state manometry. Before anesthesia, recordings were performed during normal spontaneous breathing, Valsalva and forced inspiration. The effects of anesthesia induction with remifentanil and propofol were evaluated, and positive end-expiratory pressure (PEEP) 10 cmH₂O was applied during anesthesia.

RESULTS

During spontaneous breathing, the lower esophageal sphincter (LES) pressure was significantly lower during end-expiration compared with end-inspiration (28.5 ± 7.7 vs. 35.4 ± 10.8 mmHg, P<0.01), but barrier pressure (BrP) and intra-gastric pressure (IGP) were unchanged. LES, BrP (P<0.05) and IGP (P<0.01) decreased significantly during anesthesia. BrP remained positive in all patients. IGP increased during Valsalva (P<0.01) but was unaffected by PEEP. Esophageal pressures were positive during both spontaneous breathing and mechanical ventilation. Esophageal pressures increased during PEEP from 9.4 ± 3.8 to 11.3 ± 3.3 mmHg (P<0.01).

CONCLUSION

During spontaneous breathing, the LES pressure was the lowest during end-expiration but there were no differences in BrP and IGP. LES, BrP and IGP decreased during anesthesia but BrP remained positive in all patients. During the application of PEEP, esophageal pressures increased and this may have a protective effect against regurgitation.

Circulating mitochondrial DAMPs cause inflammatory responses to injury

Injury causes a systemic inflammatory response syndrome (SIRS) clinically much like sepsis 1. Microbial pathogen-associated molecular patterns (PAMPs) activate innate immunocytes through pattern recognition receptors 2. Similarly, cellular injury can release endogenous damage-associated molecular patterns (DAMPs) that activate innate immunity 3. Mitochondria are evolutionary endosymbionts that were derived from bacteria 4 and so might bear bacterial molecular motifs. We show here that injury releases mitochondrial DAMPs (MTD) into the circulation with functionally important immune consequences. MTD include formyl peptides and mitochondrial DNA. These activate human neutrophils (PMN) through formyl peptide receptor-1 and TLR9 respectively. MTD promote PMN Ca²⁺ flux and phosphorylation of MAP kinases, thus leading to PMN migration and degranulation in vitro and in vivo. Circulating MTD can elicit neutrophil-mediated organ injury. Cellular disruption by trauma releases mitochondrial DAMPs with evolutionarily conserved similarities to bacterial PAMPs into the circulation. These can then signal through identical innate immune pathways to create a sepsis-like state. The release of such mitochondrial ‘enemies within’ by cellular injury is a key link between trauma, inflammation and SIRS.

Awareness and use of Benzodiazepines in healthy volunteers and ambulatory patients visiting a tertiary care hospital: a cross sectional survey

BACKGROUND

Indiscriminate prescription of Benzodiazepines in Pakistan and subsequent availability over-the-counter without prescription is a major public health problem, requiring systematic inquiry through research. Additionally, there is limited data on the awareness and use of Benzodiazepines from developing countries making it impossible to devise meaningful health policies.

METHODOLOGY/PRINCIPAL FINDINGS

This was an Observational, Cross-Sectional study. conducted at Aga Khan University. A total of 475 (58.5% males, 41.5% females) people visiting a tertiary care hospital were interviewed by means of a structured questionnaire. The results showed that majority of population was aware of one or more Benzodiazepines (80.4%) and 30.4% had used them at some point in life. 42.4% of the users had been using it for more than a year. Commonest reason for use was sleep disturbance. Frequency of usage was higher for females, married individuals, educated (>Grade12), high socioeconomic status and housewives. More (59%) were prescribed than not and of them most by GP (58.5%). Only 36.5% of them were particularly told about the long-term addiction potential by the use of these drugs.

CONCLUSION

Easy availability, access to re-fills without prescription and self prescription compounded with the lack of understanding of abuse potential of benzodiazepines constitutes a significant problem demanding serious consideration from health policy makers.

Gastrointestinal, selective airways and urinary bladder relaxant effects of Hyoscyamus niger are mediated through dual blockade of muscarinic receptors and Ca2+ channels

This study describes the spasmolytic, antidiarrhoeal, antisecretory, bronchodilatory and urinary bladder relaxant properties of Hyoscyamus niger to rationalize some of its medicinal uses. The crude extract of H. niger seeds (Hn.Cr) caused a complete concentration-dependent relaxation of spontaneous contractions of rabbit jejunum, similar to that caused by verapamil, whereas atropine produced partial inhibition. Hn.Cr inhibited contractions induced by carbachol (1 microM) and K(+) (80 mM) in a pattern similar to that of dicyclomine, but different from verapamil and atropine. Hn.Cr shifted the Ca(2+) concentration-response curves to the right, similar to that caused by verapamil and dicyclomine, suggesting a Ca(2+) channel-blocking mechanism in addition to an anticholinergic effect. In the guinea-pig ileum, Hn.Cr produced a rightward parallel shift of the acetylcholine curves, followed by a non-parallel shift with suppression of the maximum response at a higher concentration, similar to that caused by dicyclomine, but different from that of verapamil and atropine. Hn.Cr exhibited antidiarrhoeal and antisecretory effects against castor oil-induced diarrhoea and intestinal fluid accumulation in mice. In guinea-pig trachea and rabbit urinary bladder tissues, Hn.Cr caused relaxation of carbachol (1 microM) and K(+) (80 mM) induced contractions at around 10 and 25 times lower concentrations than in gut, respectively, and shifted carbachol curves to the right. Only the organic fractions of the extract had a Ca(2+) antagonist effect, whereas both organic and aqueous fractions had anticholinergic effect. A constituent, beta-sitosterol exhibited Ca(2+) channel-blocking action. These results suggest that the antispasmodic effect of H. niger is mediated through a combination of anticholinergic and Ca(2+) antagonist mechanisms. The relaxant effects of Hn.Cr occur at much lower concentrations in the trachea and bladder. This study offers explanations for the medicinal use of H. niger in treating gastrointestinal and respiratory disorders and bladder hyperactivity.

Variable Phenotypic Expression of Identical MYH Germline Mutations in Siblings with Attenuated Familial Adenomatous Polyposis

Germline mutations in the Mutant-Y-homologue (MYH) gene have been linked to an attenuated form of familial adenomatous polyposis in patients who express a wild-type adenomatous polyposis coli gene. However, the diverse clinical manifestations of MYH mutations have not been fully elucidated. We report a case of siblings with identical germline mutations in the MYH gene, one of whom developed a locally advanced colon adenocarcinoma with few other adenomatous lesions, whereas the other had numerous benign colonic polyps. The variable genotype–phenotype manifestations of MYH mutations and the attenuated familial adenomatous polyposis syndrome are discussed.

Variable phenotypic expression of identical MYH germline mutations in siblings with attenuated familial adenomatous polyposis

Germline mutations in the Mutant-Y-homologue (MYH) gene have been linked to an attenuated form of familial adenomatous polyposis in patients who express a wild-type adenomatous polyposis coli gene. However, the diverse clinical manifestations of MYH mutations have not been fully elucidated. We report a case of siblings with identical germline mutations in the MYH gene, one of whom developed a locally advanced colon adenocarcinoma with few other adenomatous lesions, whereas the other had numerous benign colonic polyps. The variable genotype-phenotype manifestations of MYH mutations and the attenuated familial adenomatous polyposis syndrome are discussed.

Task-switching with antisaccades versus no-go trials: a comparison of inter-trial effects

Antisaccades involve the suppression of a pre-potent prosaccade and a vector inversion to generate the novel ocular motor response of looking away from the target. Antisaccades have also been found to prolong the latencies of saccades in upcoming trials, an effect that we attribute to a form of immediate plasticity in the ocular motor system. Our goal was to determine whether the inter-trial effects of antisaccades were similar to that of no-go trials, where subjects must suppress making a saccade when the target appears without substituting a novel ocular motor response. We tested 12 subjects with two different blocks of saccadic trials. In one, prosaccades randomly alternated with antisaccades. In the other, prosaccades alternated with no-go trials. We analyzed the error rates and latencies of prosaccades that followed antisaccades versus no-go trials, compared to repeated prosaccades, to determine if inter-trial effects were present for both types of responses that required prosaccade suppression. No-go responses increased the error rates of prosaccades in the following trial less than antisaccades did. However, no-go trials had the same effect on the latencies of upcoming prosaccades as antisaccades. The inhibitory effect that prolongs the latencies of prosaccades after antisaccades likely stems from the need to inhibit a prosaccade, a function that is also required in no-go trials. The greater impairment of prosaccade accuracy after an antisaccade may reflect either additional control mechanisms involved in vector inversion or a different form of inhibitory control that operates during antisaccades and not during no-go responses.