Intraoperative assessment of the curative potential to predict survival after gastric cancer resection: A national cohort study.

BACKGROUND: The surgeon's intraoperative assessment of the curative potential of tumor resection following gastrectomy adds new information that could help clinicians and patients by predicting survival. METHODS: All patients in Sweden undergoing gastric cancer resection between 2006 and 2018 were grouped according to a prospectively registered variable; the surgeon's intraoperative assessment of the curative potential of surgery: curative, borderline curative, or palliative. Factors affecting group allocation were analyzed with multivariable logistic regression, while survival was analyzed using multivariable Cox regression and the Kaplan-Meier method. Positive predictive value (PPV) and negative predictive value (NPV) were calculated. RESULTS: Of 2341 patients undergoing gastric cancer resection, 1547 (71%) were deemed curative, 340 (15%) borderline curative, and 314 (14%) palliative (140 missing assessments). Advanced stage increased the risk of borderline curative resection (Stage III, odds ratio (OR) = 6.04, 95% confidence interval (CI) = 3.92-9.31), as did emergency surgery OR = 3.31 (1.74-6.31) and blood loss >500 mL; OR = 1.63 (1.06-2.49). Neoadjuvant chemotherapy and multidisciplinary team (MDT) discussion both decreased the risk of borderline curative resection, OR = 0.58 (0.39-0.87) and 0.57 (0.40-0.80), respectively. In multivariable Cox regression, the surgeon's assessment independently predicted worse survival for borderline curative (hazard ratio (HR) = 1.54, 95% CI = 1.29-1.83) and palliative resections (HR = 1.76, 95% CI = 1.45-2.19), compared to curative resections. The sensitivity of the surgeon's assessment of long-term survival was 96.7%. The PPV was 50.7% and the NPV was 92.1%. CONCLUSION: The surgeon's intraoperative assessment of the curative potential of gastric cancer surgery may independently aid survival prediction and is analogous to prognostication by pathologic Staging. Advanced disease, emergency surgery, and a high intraoperative blood loss, increases the risk of a borderline curative or palliative resection. Conversely, neoadjuvant treatment and MDT discussion reduce the risk of borderline curative or palliative resection.

Population-Based Cohort Study from a Prospective National Registry: Better Long-Term Survival in Esophageal Cancer After Minimally Invasive Compared with Open Transthoracic Esophagectomy.

BACKGROUND: Recent research indicates long-term survival benefits of minimally invasive esophagectomy (MIE) compared with open esophagectomy (OE) for patients with esophageal and gastroesophageal junction (GEJ) cancers, but there is a need for more population-based studies. METHODS: We conducted a prospective population-based nationwide cohort study including all patients in Sweden diagnosed with esophageal or junctional cancer who underwent a transthoracic esophagectomy with intrathoracic anastomosis. Data were collected from the Swedish National Register for Esophageal and Gastric Cancer in 2006-2019. Patients were grouped into OE and MIE including hybrid MIE (HMIE) and totally MIE (TMIE). Overall survival and short-term postoperative outcomes were compared using Cox regression and logistic regression models, respectively. All models were adjusted for age, sex, American Society of Anesthesiologists (ASA) score, clinical T and N stage, neoadjuvant therapy, year of surgery, and hospital volume. RESULTS: Among 1404 patients, 998 (71.1%) underwent OE and 406 (28.9%) underwent MIE. Compared with OE, overall survival was better following MIE (hazard ratio [HR] 0.72, 95% confidence interval [CI] 0.55-0.94), TMIE (HR 0.67, 95% CI 0.47-0.94), and possibly also after HMIE (HR 0.76, 95% CI 0.56-1.02). MIE was associated with shorter operation time, less intraoperative bleeding, higher number of resected lymph nodes, and shorter hospital stay compared with OE. MIE was also associated with fewer overall complications (odds ratio [OR] 0.70, 95% CI 0.47-1.03) as well as non-surgical complications (OR 0.64, 95% CI 0.40-1.00). CONCLUSIONS: MIE seems to offer better survival and similar or improved short-term postoperative outcomes in esophageal and GEJ cancers compared with OE in this unselected population-based cohort.

Quantitative comparison of data-driven gating and external hardware gating for 18F-FDG PET-MRI in patients with esophageal tumors.

BACKGROUND: Respiratory motion during PET imaging reduces image quality. Data-driven gating (DDG) based on principal component analysis (PCA) can be used to identify respiratory signals. The use of DDG, without need for external devices, would greatly increase the feasibility of using respiratory gating in a routine clinical setting. The objective of this study was to evaluate data-driven gating in relation to external hardware gating and regular static image acquisition on PET-MRI data with respect to SUVmax and lesion volumes. METHODS: Sixteen patients with esophageal or gastroesophageal cancer (Siewert I and II) underwent a 6-min PET scan on a Signa PET-MRI system (GE Healthcare) 1.5-2 h after injection of 4 MBq/kg 18F-FDG. External hardware gating was done using a respiratory bellow device, and DDG was performed using MotionFree (GE Healthcare). The DDG raw data files and the external hardware-gating raw files were created on a Matlab-based toolbox from the whole 6-min scan LIST-file. For comparison, two 3-min static raw files were created for each patient. Images were reconstructed using TF-OSEM with resolution recovery with 2 iterations, 28 subsets, and 3-mm post filter. SUVmax and lesion volume were measured in all visible lesions, and noise level was measured in the liver. Paired t-test, linear regression, Pearson correlation, and Bland-Altman analysis were used to investigate difference, correlation, and agreement between the methods. RESULTS: A total number of 30 lesions were included in the study. No significant differences between DDG and external hardware-gating SUVmax or lesion volumes were found, but the noise level was significantly reduced in the DDG images. Both DDG and external hardware gating demonstrated significantly higher SUVmax (9.4% for DDG, 10.3% for external hardware gating) and smaller lesion volume (- 5.4% for DDG, - 6.6% for external gating) in comparison with non-gated static images. CONCLUSIONS: Data-driven gating with MotionFree for PET-MRI performed similar to external device gating for esophageal lesions with respect to SUVmax and lesion volume. Both gating methods significantly increased the SUVmax and reduced the lesion volume in comparison with non-gated static acquisition. DDG resulted in reduced image noise compared to external device gating and static images.

Peri-anastomotic microdialysis lactate assessment after esophagectomy.

BACKGROUND: Esophagectomy is the cornerstone in curative treatment for esophageal and gastroesophageal junctional cancer. Esophageal resection is an advanced procedure with many complications, whereof anastomotic leak is the most dreaded. This study aimed to monitor the microcirculation with microdialysis analysis of local lactate levels in real-time on both sides of the esophagogastric anastomosis in totally minimally invasive Ivor-Lewis esophagectomy. MATERIALS AND METHODS: Twenty-five patients planned for esophageal resection with gastric conduit reconstruction and intrathoracic anastomosis were recruited. A sampling device, the OnZurf® Probe, along with the CliniSenz® Analyser (Senzime AB, Uppsala Sweden) was utilized for measurements. Lactate levels from both sides of the anastomosis were analysed in real time, on site, by a transportable analyser device. Measurements were made every 30 min during the first 24 h, and thereafter every 2 hours for up to 4 days. RESULTS: All probes could be positioned as planned and on the third postoperative day 19/25 and 15/25 of the esophageal and gastric probes, respectively, continued to deliver measurements. In total, 89.6% (1539/1718) and 72.4% (1098/1516) of the measurements were deemed successful. The average lactate level on the esophageal side of the anastomosis and the gastric conduit ranged between 1.1-11.5 and 0.8-7.0 mM, respectively. Two anastomotic leaks occurred, one of which had persisting high lactate levels on the gastric side of the anastomosis. CONCLUSION: Application and use of the novel CliniSenz® analyser system, in combination with the OnZurf® Probe was feasible and safe. Continuous monitoring of analytes from the perianastomotic area has the potential to improve care after esophageal resection.

Abandoning resectional intent in patients initially deemed suitable for esophagectomy: a nationwide study of risk factors and outcomes.

The main curative treatment modality for esophageal cancer is resection. Patients initially deemed suitable for resection may become unsuitable, most commonly due to signs of generalized disease or having become unfit for surgery. The aim was to assess risk factors for abandoning esophagectomy and its impact on survival. All patients diagnosed with an esophageal or gastroesophageal junction cancer in the Swedish National Register for Esophageal and Gastric Cancer from 2006-2016 were included and risk factors associated with becoming ineligible for resection were analyzed in multivariable logistic regression analysis. Overall survival was explored by multivariable Cox regression models. Among 1,792 patients planned for resection, 189 (11%) became unsuitable for resection before surgery and 114 (6%) had exploratory surgery without resection. Intermediate and high educational levels were associated with an increased probability of resection (odds ratio (OR) 1.46, 95% CI 1.05-2.05, OR 1.92, 95% CI 1.28-2.87, respectively) as was marital status (married: OR 1.37, 95% CI 1.01-1.85). Clinically advanced disease (cT4: OR 0.38, 95% CI 0.16-0.87; cN3: OR 0.27, 95% CI 0.09-0.81) and neoadjuvant treatment were associated with a decreased probability of resection (OR 0.62, 95% CI 0.46-0.88). Five-year survival for non-resected patients was only 4.5% although neoadjuvant treatment was associated with improved survival (HR 0.75, 95% CI 0.56-0.99). Non-resected patients with squamous cell carcinoma had comparatively reduced survival (HR 1.64, 95% CI 1.10-2.43). High socioeconomic status was associated with an increased probability of completing the plan to resect whereas clinically advanced disease and neoadjuvant treatment were independent factors associated with increased risk of abandoning resectional intent.

Patient education-level affects treatment allocation and prognosis in esophageal- and gastroesophageal junctional cancer in Sweden.

BACKGROUND: Low socioeconomic status and poor education elevate the risk of developing esophageal- and junctional cancer. High education level also increases survival after curative surgery. The present study aimed to investigate associations, if any, between patient education-level and treatment allocation after diagnosis of esophageal- and junctional cancer and its subsequent impact on survival. METHODS: A nation-wide cohort study was undertaken. Data from a Swedish national quality register for esophageal cancer (NREV) was linked to the National Cancer Register, National Patient Register, Prescribed Drug Register, Cause of Death Register and educational data from Statistics Sweden. The effect of education level (low; ≤9 years, intermediate; 10-12 years and high >12 years) on the probability of allocation to curative treatment was analyzed with logistic regression. The Kaplan-Meier-method and Cox proportional hazard models were used to assess the effect of education on survival. RESULTS: A total of 4112 patients were included. In a multivariate logistic regression model, high education level was associated with greater probability of allocation to curative treatment (adjusted OR: 1.48, 95% CI: 1.08-2.03, p = 0,014) as was adherence to a multidisciplinary treatment-conference (adjusted OR: 3.13, 95% CI: 2.40-4.08, p < 0,001). High education level was associated with improved survival in the patients allocated to curative treatment (HR: 0.82, 95% CI: 0.69-0.99, p = 0,036). DISCUSSION: In this nation-wide cohort of esophageal- and junctional cancer patients, including data regarding many confounders, high education level was associated with greater probability of being offered curative treatment and improved survival.

Perfusion of the gastric conduit during esophagectomy.

In esophageal cancer surgery, perfusion of the gastric conduit is a critical issue. Measurement of gastric intramucosal pH (pHi) is a method to identify anaerobic metabolism as a sign of impaired perfusion. In this study we aimed to monitor changes in the perfusion of the gastric conduit at key steps during and after esophagectomy. pHi was measured per- and postoperatively using intermittent gastric tonometry in 32 patients undergoing open, 65%, or video-assisted thoracoscopic esophagectomy for esophageal cancer. Measurements focused on the surgical steps when the vascular supply to the gastric conduit was altered. A tonometry catheter was successfully placed in all patients and a decrease in pHi (mean ± SD) was observed from baseline to after the division of the short gastric vessels (7.33 ± 0.07 to 7.29 ±  0.07, P  = 0.005). A further reduction after the ligation of the left gastric artery (7.26 ± 0.08, P  < 0.001) and after final linear stapling the gastric conduit (7.15 ± 0.13, P  < 0.001) was observed. Two hours after surgery, pHi increased (7.24 ± 0.09, P  = 0.002). In contrast to open surgery, a trend towards less reduction in pHi was seen in thoracoscopic surgery. Patients with anastomotic leaks had lower pHi on the first postoperative day (7.12 ± 0.05 vs. 7.27 ± 0.08, P  = 0.040). It can be concluded that each surgical step altering the vascular supply to the gastric conduit resulted in detectable changes, however transient, in pHi. Patients with low pHi on the first postoperative day were more prone to have clinically relevant anastomotic leaks.