Analysis of subcutaneous swine fat via deep Raman spectroscopy using a fiber-optic probe.

Since the fat content of pork is a deciding factor in meat quality grading, the use of a noninvasive subcutaneous probe for real-time in situ monitoring of the fat components is of importance to vendors and other interested parties. In this work, we developed a spectroscopic method using a fiber-optic probe for subcutaneous fat analysis that utilizes spatially offset Raman spectroscopy (SORS). Here, normalized Raman spectra were acquired as a function of spatial offset, and the relative composition of fat-to-skin was determined. We found that the Raman intensity ratio varied disproportionately depending on the fat content and that the variations of the slope were correlated to the thickness of the fat layer. Furthermore, ordinary least square (OLS) regression using two components indicated that the depth-resolved SORS spectra reflected the relative thickness of the fat layer. We concluded that the local distribution of subcutaneous fat could be measured noninvasively using a pair of fiber-optic probes.

Spectroscopic Study of Time-Varying Optical Redox Ratio in NADH/FAD Solution.

Autofluorescence imaging has been widely applied as advanced noninvasive diagnostics for in vivo and ex vivo tissues. The optical redox ratio (ORR), which is defined as the fluorescence intensity ratio between reduced nicotine adenine dinucleotide (NADH) and oxidized flavin adenine dinucleotide (FAD), has been used as a diagnostic parameter strongly, because NADH and FAD play an important role in energetic and respiratory metabolism as coenzymes. The ORR method has provided successful assessment in cancer diagnosis including breast, cervical, and oral cancer; few studies have been reported about optical and chemical interference between two molecules resulting in a change in ORR values. In this study, we investigated the variations in ORR values of NADH/FAD mixtures dissolved in tris(hydroxymethyl)aminomethane, phosphate buffer, and deionized water environments. In vitro solutions were prepared in various concentration ratios and the experimental and theoretical ORR values were obtained from fluorescence and absorption spectra in time series. Based on the spectroscopic analysis, we concluded that the inner filter effect causes an instant decrease in FAD fluorescence just after dissolution and that the oxidation-reduction coupled with oxygenation reaction results in time-varying decreases in NADH fluorescence and FAD emission.

Prognostic Value of Preoperative Systemic Inflammatory Parameters in Advanced Gastric Cancer.

BACKGROUND: The predictive value of various systemic inflammatory parameters has been reported. However, it is still unclear which inflammatory parameters are the best predictors of prognosis in advanced gastric cancer and what are their mechanisms of action. The aim of this study was to evaluate the association between preoperative systemic inflammatory parameters and overall survival (OS) in patients with advanced gastric cancer. METHODS: This retrospective study included 489 patients with stage II/III advanced gastric cancer treated at the National Cancer Center, Republic of Korea, between January 2012 and December 2015. We divided the patients into survivors and non-survivors and compared their clinicopathological characteristics. Univariate and multivariate analyses using the Cox proportional hazards model were performed to evaluate the prognostic value of inflammatory parameters. RESULTS: The absolute lymphocyte count was significantly higher in survivors (2.07 ± 0.62 × 103/µL vs. 1.88 ± 0.63 × 103/µL, p = 0.001). The neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) were marginally lower in survivors. Survival analysis revealed that the NLR and PLR were independent prognostic factors for OS. Survival was significantly different depending on NLR and PLR in the same pathologic stages. CONCLUSIONS: NLR and PLR were independent prognostic factors for OS in patients with advanced gastric cancer. Regarding single inflammatory parameters, an elevated lymphocyte count was the only factor associated with a favorable prognosis. These results suggest that the enhanced immune function of patients affects their prognosis more than the increased systemic inflammatory response.

Necessity of Individualized Approach for Gastric Subepithelial Tumor Considering Pathologic Discrepancy and Surgical Difficulty Depending on the Gastric Location.

Background: Depending on the location of gastric subepithelial tumors (SETs), surgical access is difficult with a risk of postoperative complications. This study aimed to evaluate the clinicopathological characteristics of small-sized gastric SETs and their surgical outcomes depending on location and provide considering factors for their treatment plans. Methods: This single-center, retrospective study reviewed patients who underwent surgical resection for gastric SETs (size < 5 cm). SETs were divided into benign SETs and gastrointestinal stromal tumors (GISTs) for comparison. The clinicopathological characteristics of SETs in the cardia were compared to those in the other regions. Results: Overall, 191 patients with gastric SETs (135 GISTs, 70.7%; and 56 benign SETs, 29.3%) were included. In multivariate analysis, age > 65 years (odds ratio (OR), 3.183; 95% confidence interval (CI), 1.310−7.735; p = 0.011), and non-cardiac SETs (OR, 2.472; 95% CI, 1.110−5.507; p = 0.030) were associated with a significant risk of malignancy. Compared to SETs in other locations, cardiac SETs showed more complications (3 versus 0; p = 0.000), and open conversion rates (2 versus 0; p = 0.003). However, the proportion of GISTs of SETs in the cardia is not negligible (52.9%). Conclusions: Considering the malignancy risk of SETs, active surgical resection should be considered in old age and/or location in the non-cardiac area. However, in young patients, SETs located in the gastric cardia have a considerably benign nature and are associated with poor short-term surgical outcomes. An individualized surgical approach for asymptomatic small SETs according to the gastric location is warranted.

Analysis of esophageal reflux after proximal gastrectomy measured by wireless ambulatory 24-hr esophageal pH monitoring and TC-99m diisopropyliminodiacetic acid (DISIDA) scan.

BACKGROUND AND OBJECTIVES: Reflux is one of the most common sequela after proximal gastrectomy (PG). The aim of this study was to find a predicting factor related to the character of esophageal reflux after PG. METHODS: Wireless ambulatory 24-hr pH monitoring (for acid reflux, AR) and diisopropyliminodiacetic acid hepatobiliary scan (for bile reflux, BR) were performed on 24 patients who had reflux symptoms after PG with esophagogastrostomy from July 2008 to March 2009. Endoscopic examination was done and the length of remnant stomach (LoRS) was measure by postoperative UGI series. RESULTS: Eleven patients (45.8%) had only BR, 7 (29.2%) had AR only, Two patients (8.3%) had both acid and BR, and 3 (12.5%) had neither. The LoRS along greater curvature was significantly shorter in patients with only BR (16.11 +/- 2.87 cm) than in patients with only AR (23.69 +/- 6.15 cm, P = 0.003). Severity of symptoms or esophagitis was not significantly correlated with the content of acid or BR. CONCLUSION: Reflux symptom after PG is caused by either bile or acid rather than both. Character of reflux was related to the LoRS.

Comparison of two- and three-dimensional camera systems in laparoscopic performance: a novel 3D system with one camera.

BACKGROUND: This study evaluated the effects of a three-dimensional (3D) imaging system on laparoscopy performance compared with the conventional 2D system using a novel one-camera 3D system. METHODS: In this study, 21 novices and 6 experienced surgeons performed two tasks with 2D and 3D systems in 4 consecutive days. Performance time and error as well as subjective parameters such as depth perception and visual discomforts were assessed in each session. Electromyography was used to evaluate the usage of muscles. RESULTS: The 3D system provided significantly greater depth perception than the 2D system. The errors during the two tasks were significantly lower with 3D system in novice group, but performance time was not different between the 2D and 3D systems. The novices had more dizziness with the 3D system in first 2 days. However, the severity of dizziness was minimal (less than 2 of 10) and overcome with the passage of time. About 54% of the novices and 80% of the experienced surgeons preferred the 3D system. Electromyography (EMG) showed a tendency toward less usage of the right arm and more usage of the left arm with the 3D system. CONCLUSION: The new 3D imaging system increased the accuracy of laparoscopy performance, with greater depth perception and only minimal dizziness. The authors expect that the 3D laparoscopic system could provide good depth perception and accuracy in surgery.

Predictors of timing and patterns of recurrence after curative resection for gastric cancer.

AIMS: The aim of the study was to characterize recurrence patterns and identify predictors of recurrence after curative resection. METHODS: Of 2,786 patients that underwent curative resection for gastric cancer from 2001 to 2006 at the Korean National Cancer Center, 439 (15.8%) experienced recurrence. Patterns of recurrence, clinicopathological characteristics, and therapeutic modalities were compared between 251 patients who had recurrence within 1 year (the early recurrence group) and 188 patients who had recurrence after more than a year (the late recurrence group). Multivariate analysis was performed to identify independent factors associated with the timing of recurrence. RESULTS: In the early recurrence group, the most common pattern was hematogenous metastasis, and in the late recurrence group, the most common pattern was locoregional and peritoneal recurrence. The early recurrence group was characterized by a larger tumor, frequent lymph node (LN) metastasis, and venous, and perineural invasion. Multivariate analysis showed that LN metastasis and venous invasion were independent predictors of early recurrence. Median survival after recurrence was significantly shorter in the early recurrence group (p < 0.001). CONCLUSION: Hematogeneous metastasis was more common in the early recurrence group and LN metastasis and venous invasion were independent predictors of the timing of recurrence.

The Effect of Endoscopic Resection on Short-Term Surgical Outcomes in Patients with Additional Laparoscopic Gastrectomy after Non-Curative Resection for Gastric Cancer.

PURPOSE: Endoscopic submucosal dissection (ESD) in early gastric cancer causes an artificial gastric ulcer and local inflammation that has a negative intraprocedural impact on additional laparoscopic gastrectomy in patients with noncurative ESD. In this study, we analyzed the effect of ESD on short-term surgical outcomes and evaluated the risk factors. MATERIALS AND METHODS: From January 2003 to January 2013, 1,704 patients of the National Cancer Center underwent laparoscopic gastrectomy with lymph node dissection because of preoperative stage Ia or Ib gastric cancer. They were divided into 2 groups: (1) with preoperative ESD or (2) without preoperative ESD. Clinicopathologic factors and short-term surgical outcomes were retrospectively evaluated along with risk factors such as preoperative ESD. RESULTS: Several characteristics differed between patients who underwent ESD-surgery (n=199) or surgery alone (n=1,505). The mean interval from the ESD procedure to the operation was 43.03 days. Estimated blood loss, open conversion rate, mean operation time, and length of hospital stay were not different between the 2 groups. Postoperative complications occurred in 23 patients (11.56%) in the ESD-surgery group and in 189 patients (12.56%) in the surgery-only group, and 3 deaths occurred among patients with complications (1 patient [ESD-surgery group] vs. 2 patients [surgery-only group]; P=0.688). A history of ESD was not significantly associated with postoperative complications (P=0.688). Multivariate analysis showed that male sex (P=0.008) and laparoscopic total or proximal gastrectomy (P=0.000) were independently associated with postoperative complications. CONCLUSIONS: ESD did not affect short-term surgical outcomes during and after an additional laparoscopic gastrectomy.

Transumbilical single-incision laparoscopic wedge resection for gastric submucosal tumors: technical challenges encountered in initial experience.

PURPOSE: To report the initial clinical experience with single-incision laparoscopic gastric wedge resection for submucosal tumors. MATERIALS AND METHODS: The medical records of 10 patients who underwent single-incision laparoscopic gastric wedge resection between July 2009 and March 2011 were reviewed retrospectively. The demographic data, clinicopathologic and surgical outcomes were assessed. RESULTS: The mean tumor size was 2.5 cm (range, 1.2~5.0 cm), and the tumors were mostly located on the anterior wall (4/10) or along the greater curvature (4/10), of the stomach. Nine of ten procedures were performed successfully, without the use of additional trocars, or conversion to laparotomy. One patient underwent conversion to multiport laparoscopic surgery, to get simultaneous cholecystectomy safely. The mean operating time was 66.5 minutes (range, 24~132 minutes), and the mean postoperative hospital stay was 5 days (range, 4~7 days). No serious perioperative complications were observed. Of the 10 submucosal tumors, the final pathologic report revealed 5 gastrointestinal stromal tumors, 4 schwannomas, and 1 heterotopic pancreas. CONCLUSIONS: Single-incision laparoscopic gastric wedge resection for gastric submucosal tumors is feasible and safe, when performed by experienced laparoscopic surgeons. This technique provides favorable cosmetic results, and also short hospital stay and low morbidity, in carefully selected candidates.

Is the critical pathway effective for the treatment of gastric cancer?

PURPOSE: The present study was conducted to investigate the low compliance rate of the critical pathway (CP) and whether CP is effective for treatment of gastric cancer in radical gastrectomy. METHODS: The medical records of 631 patients who had undergone radical gastrectomy with D2 lymph node dissection were reviewed. This study compared data from patients in early gastric cancer (EGC) and advanced gastric cancer (AGC) groups, which were further subdivided into general care (non-CP) and CP groups. RESULTS: The mean length of preoperative hospital stays were significantly different between the EGC and AGC patients (P < 0.05). However, there was no difference in the mean length of postoperative hospital stays between non-CP and CP groups among either EGC patients or AGC patients (P > 0.05). The postoperative and total cost of hospitalization was not statistically different between either of the groups (P > 0.05); however, the mean preoperative costs were significantly different (P < 0.05). CONCLUSION: We conclude that use of the CP following gastrectomy is unnecessary. To decrease the length of hospital stay and associated costs, preoperative examination and consultation should be performed before admission.

Laparoscopy-assisted distal gastrectomy combined with laparoscopic spleen-preserving distal pancreatectomy for the treatment of early gastric cancer with pancreatic cystic neoplasm.

The use of laparoscopy-assisted distal gastrectomy (LADG) for early gastric cancer (EGC) and laparoscopic distal pancreatectomy (LDP) for lesions of benign or borderline malignancy have gained worldwide acceptance because they are viewed as safe and feasible. A 59-year-old man was diagnosed with EGC and intraductal papillary mucinous neoplasm (IPMN) simultaneously during cancer screening. LDP was performed prior to LADG due to the possibility of splenectomy. After completing LDP, LADG was performed in the usual manner. LADG combined with spleen-preserving LDP was performed safely. The operating time was 561 minutes, and there was no intraoperative complication. The patient was discharged on postoperative 10 without any complications. No recurrence or distant metastasis occurred during the subsequent 40 months. LADG combined with spleen-preserving LDP for EGC and IPMN was found to be feasible and less invasive than open surgery.

Radiofrequency energy delivery to the anal canal: is it a promising new approach to the treatment of fecal incontinence?

BACKGROUND: The present study was conducted to assess the efficacy and safety of the delivery of radiofrequency energy to the anal canal (the SECCA procedure). METHODS: Eight patients with fecal incontinence underwent the SECCA procedure. The Fecal Incontinence Severity Index (FISI) score and the Fecal Incontinence-related Quality of Life (FIQL) scale were completed at baseline and after the procedure. Anorectal manometry and endoanal ultrasound also were conducted. RESULTS: Seven of the 8 patients were women, and the median age of the patients was 59 years (range, 28-73 y). The mean FISI score and all of the parameters in the FIQL scale with the exception of the embarrassment scale measured at 6 months after the procedure was not improved significantly. We observed no changes in the anal manometry and endoanal ultrasound parameters. Complications associated with the procedure developed in 7 of the 8 patients, including anal bleeding, anal pain, and anal mucosal discharge. CONCLUSIONS: The FISI score and FIQL scale were not improved significantly after the SECCA procedure, and considerable complications were associated with the procedure.

Gastric choriocarcinoma admixed with an alpha-fetoprotein-producing adenocarcinoma and separated adenocarcinoma.

We report a case of gastric choriocarcinoma admixed with an alpha-fetoprotein (AFP)-producing adenocarcinoma. A 70-year-old man was hospitalized for gastric cancer that was detected during screening by esophagogastroduodenoscopy (EGD). Initial laboratory data showed the increased serum level of AFP and EGD revealed a 5-cm ulcerofungating mass in the greater curvature of the gastric antrum. The patient underwent radical subtotal gastrectomy with D2 lymph node dissection and Billroth II gastrojejunostomy. Histopathological evaluation confirmed double primary gastric cancer: gastric choriocarcinoma admixed with an AFP-producing adenocarcinoma and separated adenocarcinoma. At 2 wk postoperatively, his human chorionic gonadotropin and AFP levels had reduced and six cycles of adjuvant chemotherapy were initiated. No recurrence or distant metastasis was observed at 4 years postoperatively.