Biomechanical behavior of PMMA 3D printed biomimetic scaffolds: Effects of physiologically relevant environment.

Functional cellular structures with controllable mechanical and morphological properties are of great interest for applications including tissue engineering, energy storage, and aerospace. Additive manufacturing (AM), also referred to as 3D printing, has enabled the potential for fabrication of functional porous scaffolds (i.e., meta-biomaterials) with controlled geometrical, morphological, and mechanical properties. Understanding the biomechanical behavior of 3D printed porous scaffolds under physiologically relevant loading and environmental conditions is crucial in accurately predicting the in vivo performance. This study was aimed to investigate the environmental dependency of the mechanical responses of 3D printed porous scaffolds of poly(methyl methacrylate) (PMMA) Class IIa biomaterial that was based on triply periodic minimal surfaces - TPMS (i.e., Primitive and Schoen-IWP). The 3D printed scaffolds (n = 5/study group) were tested under compressive loading in both ambient and fluidic (distilled water with pH = 7.4) environments according to ASTM D1621 standards. Outcomes of this study showed that compressive properties of the developed scaffolds are significantly lower in the fluidic condition than the ambient environment for the same topological and morphological group (p≤0.023). Additionally, compressive properties and flexural stiffness of the studied scaffolds were within the range of trabecular bone's properties, for both topological classes. Relationships between predicted mechanical responses and morphological properties (i.e., porosity) were evaluated for each topological class. Quantitative correlation analysis indicated that mechanical behavior of the developed 3D printed scaffolds can be controlled based on both topology and morphology.

Metastasectomy for Stage IVA Colon Cancer: Does the Type of Treating Institution Make a Difference?

Treatment of metastatic colon cancer has evolved over time. More evidence has been emerging in recent years supporting metastasectomy in selected patients. We sought to elucidate whether the type of institution-community, comprehensive community, academic/research, and integrated cancer network-would have an effect on patient outcome, specifically those colon cancer patients with isolated liver metastasis. This retrospective cohort study queried the National Cancer Database (NCDB) from 2010 to 2014 for patients who were 18 years of age or older with stage IVA colon cancer with isolated liver metastasis. We then performed uni- and multivariate analyses comparing patients based on such factors as age, tumor characteristics, primary tumor location, rate of chemotherapy, and type of treating institution. Patients who came from regions of higher income, receiving chemotherapy, and presenting to an academic/research hospital were more likely to undergo metastasectomy. Median survival was longest at academic/community hospitals at 22.4 months, 6 to 7 months longer than the other three types of institutions. Factors positively affecting survival included receiving chemotherapy, presenting to an academic/research institution, and undergoing metastasectomy, all at P < .05. In our study, the rate of metastasectomy was more than double at academic/research institutions for those with stage IVA colon cancer with isolated liver metastasis. Prior studies have quoted a mere 4.1% synchronous colon resection and metastasectomy. Our findings suggest that we should maintain multidisciplinary approach to this complex disease process and that perhaps it is time for us to consider regionalization of care in treating metastatic colon cancer.

Puff-Resolved Analysis and Selected Quantification of Chemicals in the Gas Phase of E-Cigarettes, Heat-Not-Burn Devices, and Conventional Cigarettes Using Single-Photon Ionization Time-of-Flight Mass Spectrometry (SPI-TOFMS): A Comparative Study.

INTRODUCTION: A wide array of alternative nicotine delivery devices (ANDD) has been developed and they are often described as less harmful than combustible cigarettes. This work compares the chemical emissions of three ANDD in comparison to cigarette smoke. All the tested ANDD are characterized by not involving combustion of tobacco. AIMS AND METHODS: Single-photon ionization time-of-flight mass spectrometry (SPI-TOFMS) is coupled to a linear smoking machine, which allows a comprehensive, online analysis of the gaseous phase of the ANDD aerosol and the conventional cigarette (CC) smoke. The following devices were investigated in this study: a tobacco cigarette with a glowing piece of coal as a heating source, an electric device for heating tobacco, and a first-generation electronic cigarette. Data obtained from a standard 2R4F research cigarette are taken as a reference. RESULTS: The puff-by-puff profile of all products was recorded. The ANDD show a substantial reduction or complete absence of known harmful and potentially harmful substances compared with the CC. In addition, tar substances (i.e. semivolatile and low volatile aromatic and phenolic compounds) are formed to a much lower extent. Nicotine, however, is supplied in comparable amounts except for the investigated electronic cigarette. CONCLUSIONS: The data show that consumers switching from CC to ANDD are exposed to lower concentrations of harmful and potentially harmful substances. However, toxicological and epidemiological studies must deliver conclusive results if these reduced exposures are beneficial for users. IMPLICATIONS: The comparison of puff-resolved profiles of emissions from different tobacco products, traditional and alternative, may help users switch to lower emission products. Puff-resolved comparison overcomes technical changes, use modes between products and may help in their regulation.

Robotic Versus Laparoscopic Gastrectomy for Gastric Adenocarcinoma: Propensity-Matched Analysis.

Background. We compared the outcomes of laparoscopic-assisted (LA) and robotic-assisted (RA) gastrectomies performed for gastric adenocarcinoma in the National Cancer Database. Methods. The National Cancer Database was queried for patients 18 years old with stages I to III gastric adenocarcinoma who underwent LA or RA gastrectomy. Propensity matching was performed between the 2 groups with regard to clinical staging, adjuvant treatment, demographics, and the extent of surgery. Results. A cohort of 1893 (1262 = LA, 631 = RA) patients was identified in a 2:1 propensity matching. The groups were well matched. The rate of negative margin as well as 30- and 90-day mortality were similar between the 2 cohorts. Long-term survival was similar between the 2 groups (median survival 49.2 months in LA vs 56.2 months for RA, P = .405). However, the average number of lymph nodes (LNs) sampled was significantly higher in the RA group compared with the LA group (19.6 vs 17.4, P < .001). Similarly, the percentage of surgeries in which ≥15 LNs were sampled was also greater in the RA group compared with the LA group (63.9% vs 57.6%, P = .010). On multivariable analysis, having 15 LNs or more examined was associated with better survival (hazard ratio = 0.72, 95% confidence interval = 0.60-0.87, P < .001). Advanced age, nodal positivity, and advanced clinical stages were significantly associated with worse survival. Conclusions. RA gastrectomy may allow a greater harvest of LNs, and thus more accurate staging, without increasing short-term adverse outcomes compared with LA gastrectomy. Short-term and long-term outcomes in this well-matched cohort appear comparable for both approaches.

Trends and Outcomes of Synchronous Resection of Colorectal Metastasis in the Modern Era-Analysis of Targeted Hepatic NSQIP Database.

BACKGROUND: Previous studies using the NSQIP database to study hepatectomies lacked hepatic specific variables and outcomes. We used the targeted NSQIP hepatectomy database to examine the nationwide trend and the safety profile of synchronous liver and colorectal resection compared with hepatectomy alone for colorectal liver metastasis. METHODS: The targeted NSQIP hepatectomy database from 2014 was used to study patients who underwent hepatectomy for diagnosis of adenocarcinoma of the colon and rectum. RESULTS: Of the 3064 hepatic resections in the database, 1138 cases were performed for colorectal metastasis. Of these, 1040 were liver-alone surgery and 98 were synchronous liver and colorectal resection. Most (58.7%) patients received neoadjuvant therapy. The rate of neoadjuvant therapy, intraoperative ablation, biliary reconstruction, and the use of minimally invasive technique were similar between the two groups. The overall 30-d mortality in this cohort was low (1.1%). While the mortality rate in the synchronous group was similar to liver-only group (3.1% versus 0.9%, P = 0.077). The rate of liver failure (3.3% versus 4.1%, P = 0.722) and biliary leak (5.3% versus 9.6%, P = 0.084) were similar between the two groups. However, the rate of major complications was higher on multivariable analyses (25.5% versus 12.1%, OR 2.5, 95% CI 1.5-4.1, P < 0.001) for the synchronous group. CONCLUSIONS: Hepatic resection for colorectal metastasis in the modern era has low short-term mortality. While synchronous resection was associated with a higher incidence of major complications, liver-specific complications did not increase with synchronous resection.

Racial disparities in breast cancer persist despite early detection: analysis of treatment of stage 1 breast cancer and effect of insurance status on disparities.

PURPOSE: Prior research demonstrates racial disparities in breast cancer treatment. Disparities are commonly attributed to more advanced stage at presentation or aggressive tumor biology. We seek to evaluate if racial disparities persist in the treatment of stage 1 breast cancer patients who by definition are not delayed in presentation. METHODS: We selected stage 1 breast cases in the National Cancer Data Base. Patients were divided into two cohorts based on race and included White and Black patients. We also performed a subgroup analysis of patients with private insurance for comparison to determine if private insurance diminished the racial disparities noted. We analyzed differences in time to treatments by race. RESULTS: Our analysis included 546,351 patients of which 494,784 (90.6%) were White non-Hispanic and 51,567 (9.4%) were Black non-Hispanic. Black women had significantly longer times to first treatment (35.5 days vs 28.1 days), surgery (36.6 days vs 28.8 days), chemotherapy (88.1 days vs 75.4 days), radiation (131.3 days vs 99.1 days), and endocrine therapy (152.1 days vs 126.5 days) than White women. When patients with private insurance were analyzed the difference in time to surgery decreased by 1.2 days but racial differences remained statistically significant. CONCLUSIONS: Despite selecting for early-stage breast cancer, racial disparities between White and Black women in time to all forms of breast cancer treatment persist. These disparities while likely not oncologically significant do suggest institutional barriers for obtaining care faced by women of color which may not be addressed with improving access to mammography alone.

Outcomes associated with resident involvement in ventral hernia repair: A population based study using the NSQIP database.

INTRODUCTION: This study evaluated the effect of resident involvement on patient outcomes following major ventral hernia repair (VHR). METHODS: National Surgical Quality Improvement Program database was queried to identify patients with major VHR between 2007 and 2010. Patient outcomes were compared based on presence or absence of resident in the operating room. RESULTS: Residents participated in 57% of the 27,773 identified cases. There was no significant difference in return to operating room or 30-day mortality. A higher incidence of superficial surgical site infection (SSI) (4.9% vs 3.9%, P = 0.013) and longer operative time (129.2 vs 99.1 min, P < 0.001) were observed with resident involvement in open inpatient cases. We found no evidence of a "July effect" on outcomes. CONCLUSION: Resident involvement in VHR has little impact on morbidity, and patients can be reassured that resident participation in their care is safe.

Preoperative Panel Testing for Hereditary Cancer Syndromes Does Not Significantly Impact Time to Surgery for Newly Diagnosed Breast Cancer Patients Compared with BRCA1/2 Testing.

BACKGROUND: This study seeks to determine whether there is a delay in time to surgery in breast cancer patients with panel tests compared with traditional BRCA testing. METHODS: This study was a retrospective review of women diagnosed with breast cancer who underwent genetic evaluation from our institution's Genetic Counselor Database from January 2013 to August 2015. Patients were excluded if they were male, clinical information was unavailable, the patient underwent neoadjuvant chemotherapy, had a diagnosis of recurrent breast cancer during time of study, or had postoperative genetics evaluation. RESULTS: Included in the study were 138 patients. The time from diagnosis to surgery for BRCA1/2 tested patients was 43.5 days compared with 51.0 days in the panel group (p = 0.186). Turnaround time for genetic testing decreased during the period studied and was approximately 6 days longer for panel testing than BRCA testing. It took 12.2 days for BRCA results and 18.9 days for the panel results (p < 0.01). Turnaround time for BRCA1/2 testing in 2014 and 2015 was 12.4 and 10.5 days respectively, whereas panel testing was 20.5 and 18.2 days (p ≤ 0.001). Of the variables included in multivariable linear regression, only mastectomy significantly contributed to time to surgery (p < 0.001). DISCUSSION: Panel genetic testing did not delay time to surgery compared with BRCA testing alone. The use of panel testing has increased over time, and lab turnaround time has decreased. Mastectomy was the only clinical variable contributing to longer time to surgery.

Urinary Retention Following Colorectal Surgery.

Literature on postoperative urinary retention (POUR) after colorectal resections is limited. The aim of our study was to evaluate the incidence of and risk factors for POUR after elective colorectal resections in men ≥55 years without genitourinary issues. A retrospective review of elective colorectal resections (June 1, 2014 to June 1, 2015) in men ≥55 years without genitourinary conditions was performed at our institution. Patient demographics, American Society of Anesthesiologist score, body mass index (BMI), surgical history, type of disease, extent of resection, surgical approach, operating room (OR) time, volume of OR fluids administered, and intra- and postoperative urine output were included for analysis. Seventy patients were identified. Nine (12.9%) experienced POUR. Patients with POUR experienced longer OR time (324 vs 239 minutes; P = 0.048) and had a lower median BMI (23.8 vs 28 kg/m2; P = 0.038). There were no significant differences in regards to age, comorbidities, diagnosis, type of resection, surgical approach, intravenous fluids administered operatively, or postoperative urine output. The incidence of POUR in male patients at least 55 years of age after elective colorectal resection in our institution was 12.9 per cent. Longer operative time and lower BMI were associated with a higher incidence of POUR.

The role of hepatic artery lymph node in pancreatic adenocarcinoma: prognostic factor or a selection criterion for surgery.

BACKGROUND: Hepatic artery lymph node (HALN) metastasis in pancreatic adenocarcinoma reportedly confers a survival disadvantage. This has led some authors to propose it as an indicator against pancreaticoduodenectomy (PD). METHODS: Consecutive patients who underwent PD during 2002-2012 were identified from the University of Louisville prospective hepatopancreaticobiliary database. Overall survival (OS) and disease-free survival (DFS) were estimated using Kaplan-Meier analysis. The log-rank test and multivariate Cox proportional hazards regression were used in further analyses. RESULTS: A total of 420 patients underwent PD during the period of study, of whom 197 had lymph node (LN) metastasis. Among these, 41 (20.8%) patients had disease-positive HALNs. The HALN was the only site of LN metastasis in only three of the 247 patients (1.2%). Median follow-up was 18.5 months (interquartile range: 4.1-28.2 months). Median OS and DFS were 22.7 months [95% confidence interval (CI) 19.0-26.3] and 12.6 months (95% CI 10.2-15.2). There was no significant difference in median OS between HALN-positive patients (18.4 months, 95% CI 12.3-24.0) and HALN-negative patients (19.7 months, 95% CI 16.7-22.6) (P = 0.659). On multivariate analysis, the hazard ratio (HR) of death was highest among patients with an LN ratio of >0.2 (HR 1.2, 95% CI 1.1-1.29; P = 0.012) followed by those with poorly differentiated histology (HR 1.09, 95% CI 1.04-1.11; P = 0.029). CONCLUSIONS: In pancreatic adenocarcinoma patients with LN disease, survival after PD is comparable regardless of HALN status. Therefore, HALN-positive disease should not preclude the performance of PD.

Evaluation of resistance as a measure of successful tumor ablation during irreversible electroporation of the pancreas.

BACKGROUND: Intraoperative evaluation of successful pancreatic tumor ablation using irreversible electroporation (IRE) is difficult secondary to lack of visual confirmation. The IRE generator provides feedback by reporting current (amperage), which can be used to calculate changes in tumor tissue resistance. The purpose of the study was to determine if resistance can be used to predict successful tumor ablation during IRE for pancreatic cancers. STUDY DESIGN: All patients undergoing pancreatic IRE from March 2010 to December 2012 were evaluated using a prospective database. Intraoperative information, including change in tumor resistance during ablation and slope of the resistance curve, were used to evaluate effectiveness of tumor ablation in terms of local failure or recurrence (LFR) and disease-free survival (DFS). RESULTS: A total of 65 patients underwent IRE for locally advanced pancreatic cancer. Median follow-up was 23 months. Local failure or recurrence was seen in 17 patients at 3, 6, or 9 months post IRE. Change in tumor tissue resistance and the slope of the resistance curve were both significant in predicting LFR (p = 0.02 and p = 0.01, respectively). The median local disease-free survival was 5.5 months in patients who had recurrence compared with 12.6 months in patients who did not recur (p = 0.03). Neither mean change in tumor tissue resistance nor the slope of the resistance curve significantly predicted overall DFS. CONCLUSIONS: Mean change in tumor tissue resistance and the slope of the resistance curve could be used intraoperatively to assess successful tumor ablation during IRE. Larger sample size and longer follow-up are needed to determine if these parameters can be used to predict DFS.

Stroke volume variation in hepatic resection: a replacement for standard central venous pressure monitoring.

BACKGROUND: Central venous pressure (CVP) is the standard method of volume status evaluation during hepatic resection. CVP monitoring requires preoperative placement of a central venous catheter (CVC), which can be associated with increased time, cost, and adverse events. Stroke volume variation (SVV) is a preload index that can be used to predict an individual's fluid responsiveness through an existing arterial line. The purpose of this study was to determine if SVV is as safe and effective as CVP in measuring volume status during hepatic resection. METHODS: Two cohorts of 40 consecutive patients (80 total) were evaluated during hepatic resection between December 2010 and August 2012. The initial evaluation group of 40 patients had continuous CVP monitoring and SVV monitoring performed simultaneously to establish appropriate SVV parameters for hepatic resection. A validation group of 40 patients was then monitored with SVV alone to confirm the accuracy of the established SVV parameters. Type of hepatic resection, transection time, blood loss, complications, and additional operative and postoperative factors were collected prospectively. SVV was calculated using the Flotrac™/Vigileo™ System. RESULTS: The evaluation group included 40 patients [median age 62 (29-82) years; median body mass index (BMI) 27.7 (16.5-40.6)] with 18 laparoscopic, 22 open, and 24 undergoing major (≥3 segments) hepatectomy. Median transection times were 43 (range 20-65) min, median blood loss 250 (range 20-950) cc, with no Pringle maneuver utilized. In this evaluation group, a CVP of -1 to 1 significantly correlated to a SVV of 18-21 (R (2) = 0.85, p < 0.001). The validation group included 40 patients [median age 61 (35-78) years; median BMI 28.1 (17-41.2)], with 24 laparoscopic, 16 open, and 33 undergoing major hepatectomy. Using a SVV goal of 18 to 21, median transection time was 55 (25-78) min, median blood loss of 255 (range 100-1,150) cc, again without the use of a Pringle maneuver. CONCLUSIONS: SVV can be used safely as an alternative to CVP monitoring during hepatic resection with equivalent outcomes in terms of blood loss and parenchymal transection time. Using SVV as a predictor of fluid status could prove to be advantageous by avoiding the need for CVC insertion and therefor eliminating the risk of CVC related complications in patients undergoing hepatic resection.

Clinical evaluation of somatostatin use in pancreatic resections: Clinical efficacy or limited benefit?

BACKGROUND: The benefit of somatostatin for the prevention of pancreatic fistula has been debated widely in the literature. The aim of this study was to evaluate the efficacy of somatostatin in preventing pancreatic fistulas and improving postoperative outcomes after pancreatic resection. HYPOTHESIS: Somatostatin improves postoperative outcomes after pancreatectomy. METHODS: A review was performed of a prospectively collected 2002 patient hepatopancreaticobiliary database. Patients were included if they underwent pancreatectomy between October 1, 2000, and May 16, 2012. Patients received somatostatin prophylactically at the discretion of their surgeon. Data were analyzed using univariate and multivariate analysis to determine if somatostatin had any effect on pancreatic fistula formation, fistula severity, duration of stay, and readmission rates. RESULTS: We identified 510 patients who underwent pancreatectomy. Overall, patients 30 (6%) developed postoperative pancreatic fistulas and 27 (5%) fistulas were of clinical significance (grade B or C). Somatostatin was administered prophylactically to 215 (42%) patients, 57 patients (11%) were readmitted; the median duration of stay was 9 days (range, 2-81). Pancreatic fistula developed in 7 patients (3%) who received somatostatin versus 23 (8%) who did not receive somatostatin (P = .031). Among patients receiving somatostatin, 6 fistulas (3%) were of clinical significance versus 21 fistulas (7%) for patients who did not receive somatostatin (P = .031). Readmission occurred in 27 patients (13%) who received somatostatin versus 30 patients (10%) who did not receive somatostatin (P = .398). The median duration of stay was 9 days (range, 2-48) for patients who received somatostatin versus 9 days (range, 2-81) for patients who did not receive somatostatin (P = .462). CONCLUSION: Somatostatin use was associated with a significant decrease in both the rate of fistula formation and the number of clinically important fistulas in our pancreatectomy patients. Continued evaluation of somatostatin use in relation to both intraoperative predictors and costa are needed to better define the population that will gain clinical benefit and cost savings.

Evaluation of alpha-fetoprotein staging system for hepatocellular carcinoma in noncirrhotic patients.

The Barcelona Clinic Liver Cancer (BCLC) staging classification is commonly used for staging hepatocellular carcinoma (HCC). This system assumes the coexistence of cirrhosis; however, a significant proportion of patients with HCC present without cirrhosis. Recently, an alternative system was proposed that stratifies patients according to alpha-fetoprotein (AFP) level. The aim of this study was to apply the AFP staging system to noncirrhotic patients with HCC and evaluate its ability to predict overall survival (OS). A prospective hepatopancreatobiliary database was reviewed for all patients with a diagnosis of HCC. Patients were staged based on BCLC classification as well as by AFP stage according to four levels: less than 10 ng/mL, 10 to 150 ng/mL, 150 to 500 ng/mL, and greater than 500 ng/mL. Cirrhotic patients were compared with noncirrhotic patients in terms of patient demographics and HCC stage. Kaplan-Meier (KM) analysis of OS was performed for noncirrhotic patients according to BCLC and AFP staging systems. Cirrhotic and noncirrhotic patients differed significantly in terms of median age at presentation (64 vs 70 years, P < 0.001) and gender (76 vs 65% male, P = 0.006). BCLS staging classification did not distinguish between cirrhotics and noncirrhotics (P = 0.733), whereas AFP staging demonstrated a significant difference between the two groups (P < 0.0001). KM analysis of OS for noncirrhotic patients with HCC was significant for both the BCLC and the AFP staging systems (P = 0.003 vs P < 0.0001, respectively). Patients presenting with HCC in the absence of cirrhosis appear to have different characteristics than patients with cirrhosis. Staging according to AFP level is an appropriate predictor of prognosis in noncirrhotic patients with HCC.

Incidence of sentinel lymph node involvement in a modern, large series of desmoplastic melanoma.

BACKGROUND: Recent studies have suggested that sentinel lymph node (SLN) biopsy is of limited value in desmoplastic melanoma. This study was performed to compare the rate of positive SLN biopsy in the Surveillance, Epidemiology, and End Results (SEER) database with that of a multi-institutional clinical trial and to investigate relevant prognostic factors in desmoplastic melanoma. STUDY DESIGN: Patients with desmoplastic melanoma ≥1.0 mm Breslow thickness, who underwent SLN biopsy in a multi-institutional prospective clinical trial, were combined with a single institution melanoma database (combined database) and compared with patients from the SEER database (1998 to 2009). Disease-free survival (DFS) and overall survival (OS) were summarized using Kaplan-Meier curves and compared using Cox proportional hazard models. RESULTS: The rate of positive SLN in the combined database was 17.0% (8 of 47). By comparison, the rate of positive SLN in SEER was lower: 2.5% (15 of 594). On multivariable analysis, Breslow thickness ≥2.6 mm (hazard ratio 8.17, 95% CI 1.26 to 160.1; p = 0.0259) and an interaction between SLN status and ulceration (p = 0.0013) were independent risk factors for worse OS in the combined database; patients with ulceration and a positive SLN had significantly worse OS. In the combined database on multivariable analysis, SLN positivity (p = 0.0161) and ulceration (p = 0.0004) were independent risk factors for worse DFS. CONCLUSIONS: The rate of positive SLN in desmoplastic melanoma may be higher than that reported in the SEER database. Sentinel lymph node biopsy may be considered as part of the comprehensive staging of desmoplastic melanoma ≥1.0 mm Breslow thickness.

Outcomes and prognostic factors in nodular melanomas.

BACKGROUND: The nodular subtype of cutaneous melanoma has a more pronounced vertical phase and less of a radial growth phase compared with other histologic subtypes. This study was performed to determine prognostic factors and outcomes for nodular melanomas. METHODS: A post hoc analysis of a prospective clinical trial was performed in all patients with nodular histologic subtype. Univariate and multivariate analyses of factors associated with disease-free survival (DFS), overall survival (OS), and local and in-transit recurrence-free survival (LITRFS) were performed. Kaplan-Meier survival analyses were performed. RESULTS: There were 736 patients available for analysis, and 189 (25.7%) were sentinel lymph node (SLN) positive. Breslow thickness of ≥2.3 mm, presence of ulceration, nonextremity tumor location, positive SLN, and non-SLN-positive status were independent risk factors for worse OS and DFS. Kaplan-Meier analysis demonstrated that ulceration predicted worse OS and DFS in all nodular melanoma patients, and in both SLN-positive and -negative subsets. The presence of ulceration and a positive SLN together predicted significantly worse DFS and OS. CONCLUSION: The most important risk factors that determine prognosis in nodular melanomas are SLN status and ulceration. The presence of both a positive SLN and ulceration significantly affect DFS and OS, and to a lesser degree LITRFS.

Clinicopathologic and survival differences between upper and lower extremity melanomas.

This analysis was performed to compare differences in clinicopathologic factors, sentinel lymph node (SLN) status, and survival between upper extremity (UE) and lower extremity (LE) melanoma patients. Post hoc analysis of a prospective clinical trial was performed of all patients with extremity melanomas with complete data. Survival was evaluated with Kaplan-Meier analysis. Univariate and multivariate analyses were performed. A total of 1115 patients aged 18 to 70 years with extremity melanomas ≥ 1.0 mm Breslow thickness were analyzed; all underwent SLN biopsy with completion lymphadenectomy for a tumor-positive SLN. Compared with UE patients, LE melanoma patients were younger, predominantly female, and had a higher rate of SLN metastasis. Kaplan-Meier analysis revealed worse 5-year disease-free survival (DFS) and worse local and in-transit recurrence-free survival in LE versus UE melanoma patients, but no difference in overall survival (OS). Subgroup analysis revealed that older patients (age > 51 years) with LE melanomas had worse DFS, local and in-transit recurrence-free-survival, and OS. LE tumor location was not an independent risk factor for OS or DFS. Compared with UE melanoma patients, those with LE melanomas have a greater risk of tumor-positive SLN and local/in-transit recurrence.

Clinically unsuspected papillary microcarcinomas of the thyroid: a common finding with favorable biology?

BACKGROUND: The purpose of this study was to describe the incidence and clinical/pathologic characteristics of papillary thyroid microcarcinoma (PMC) in a community hospital setting and to evaluate the frequency and characteristics of these lesions when unsuspected preoperatively. METHODS: A total of 723 patients underwent a partial or total thyroidectomy. A retrospective review was performed. RESULTS: A total of 194 of the 723 patients had a final diagnosis of papillary carcinoma. Ninety-six (49%) of these tumors were PMCs defined as being 1.0 cm or less in diameter. One third (32 of 96) of these lesions were multifocal and 16.7% (16 of 96) were found to have regional lymph node metastases. The majority (58%) of PMCs were found on final pathology and were clinically unsuspected (occult). Multifocality was found in 32.1% (18 of 56) of patients with clinically unsuspected PMC, with nodal metastases in 3.6% (2 of 56). The other 40 patients with PMC had surgeries performed for a clinical reason related to that pathologic lesion. This clinically suspected group was comparably multifocal (35%), but more likely to have cervical lymph node metastasis (35%). Sixty-six percent (37 of 56) diagnosed with a clinically unsuspected PMC underwent a partial thyroidectomy at the initial surgery. CONCLUSIONS: The prevalence of clinically unsuspected PMC in our population undergoing thyroidectomy was 7.7% (56 of 723). In our institution, this is more than half of all PMCs. The incidence of cervical lymph node metastasis in clinically unsuspected PMC was only 3.6% compared with 35% in clinically suspected disease, suggesting that the biological behavior (and possibly treatment) may be different. Long-term follow-up evaluation is needed to better evaluate the significance of these differences.

Endoscopic therapy for Barrett's esophagus: a review of its emerging role in optimal diagnosis and endoluminal therapy.

Barrett's esophagus (BE) is a premalignant lesion known to sequentially progress to esophageal adenocarcinoma. Management of BE has changed significantly over the last 5 years with the development of endoscopic resection and ablation, which has replaced esophagectomy as the treatment of choice in BE with high-grade dysplasia. The aim of this review is to discuss the details of these new endotherapies in regards to response and durability and to define the role of these new therapies in the current management of BE.