The preliminary analysis of lymphatic flow around the connective tissues surrounding SMA and SpA elucidates patients' oncological condition in borderline-resectable pancreatic cancer

BACKGROUND

In pancreatic ductal adenocarcinoma (PDAC), invasion of connective tissues surrounding major arteries is a crucial prognostic factor after radical resection. However, why the connective tissues invasion is associated with poor prognosis is not well understood.

MATERIALS AND METHODS

From 2018 to 2020, 25 patients receiving radical surgery for PDAC in our institute were enrolled. HyperEye Medical System (HEMS) was used to examine lymphatic flow from the connective tissues surrounding SMA and SpA and which lymph nodes ICG accumulated in was examined.

RESULTS

HEMS imaging revealed ICG was transported down to the paraaortic area of the abdominal aorta along SMA. In pancreatic head cancer, 9 paraaortic lymph nodes among 14 (64.3%) were ICG positive, higher positivity than LN#15 (25.0%) or LN#18 (50.0%), indicating lymphatic flow around the SMA was leading directly to the paraaortic lymph nodes. Similarly, in pancreatic body and tail cancer, the percentage of ICG-positive LN #16a2 was very high, as was that of #8a, although that of #7 was only 42.9%.

CONCLUSIONS

Our preliminary result indicated that the lymphatic flow along the connective tissues surrounding major arteries could be helpful in understanding metastasis and improving prognosis in BR-A pancreatic cancer.

Risk factors for abdominal surgical infectious complications after distal gastrectomy for gastric cancer: A post-hoc analysis of a randomized controlled trial (JCOG0912)

BACKGROUND

Abdominal surgical infectious complications (ASIC) after gastrectomy for gastric cancer impair patients' survival and quality of life. JCOG0912 was conducted to compare laparoscopy-assisted distal gastrectomy with open distal gastrectomy for clinical stage IA or IB gastric cancer. The present study aimed to identify risk factors for ASIC using prospectively collected data.

METHODS

We performed a post-hoc analysis of the risk factors for ASIC using the dataset from JCOG0912. All complications were evaluated according to the Clavien-Dindo classification (CD). ASIC was defined as CD grade I or higher anastomotic leakage, pancreatic fistula, abdominal abscess, and wound infection. Analyses were performed using the logistic regression model for univariable and multivariable analyses.

RESULTS

A total of 910 patients were included (median age, 63 years; male sex, 61 %). Among them, ASIC occurred in 5.8 % of patients. In the univariable analysis, male sex (odds ratio [OR] 2.855, P = 0.003), diabetes (OR 2.565, P = 0.029), and Roux-en-Y (R-Y) reconstruction (vs. Billroth Ⅰ, OR 2.707, P = 0.002) were significant risk factors for ASIC. In the multivariable analysis, male sex (OR 2.364, P = 0.028) and R-Y reconstruction (vs. Billroth Ⅰ, OR 2.310, P = 0.015) were independent risk factors for ASIC.

CONCLUSIONS

Male sex and R-Y reconstruction were risk factors for ASIC after distal gastrectomy. Therefore, when performing surgery on male patients or when R-Y reconstruction is selected after gastrectomy for gastric cancer, surgeons should pay special attention to prevent ASIC.

Significance of Comprehensive Analysis of Preoperative Sarcopenia Based on Muscle Mass, Muscle Strength, and Physical Function for the Prognosis of Patients with Esophageal Cancer

BACKGROUND

The assessment of muscle mass loss, muscle strength, and physical function has been recommended in diagnosing sarcopenia. However, only muscle mass has been assessed in previous studies. Therefore, this study investigated the effect of comprehensively diagnosed preoperative sarcopenia on the prognosis of patients with esophageal cancer.

METHODS

The study analyzed 115 patients with esophageal cancer (age ≥ 65 years) who underwent curative esophagectomy. Preoperative sarcopenia was analyzed using the skeletal mass index (SMI), handgrip strength, and gait speed based on the Asian Working Group for Sarcopenia 2019 criteria. Clinicopathologic factors, incidence of postoperative complications, and overall survival (OS) were compared between the sarcopenia and non-sarcopenia groups. The significance of the three individual parameters also was evaluated.

RESULTS

The evaluation identified 47 (40.9%) patients with low SMI, 31 (27.0%) patients with low handgrip strength, and 6 (5.2%) patients with slow gait speed. Sarcopenia was diagnosed in 23 patients (20%) and associated with older age and advanced pT stage. The incidence of postoperative complications did not differ significantly between the two groups. Among the three parameters, only slow gait speed was associated with Clavien-Dindo grade 2 or greater complications. The sarcopenia group showed significantly worse OS than the non-sarcopenia group. Those with low handgrip strength tended to have worse OS, and those with slow gait speed had significantly worse OS than their counterparts.

CONCLUSIONS

Preoperative sarcopenia diagnosed using skeletal muscle mass, muscle strength, and physical function may have an impact on the survival of patients with esophageal cancer.

Phase II Study of Intraperitoneal Administration of Paclitaxel Combined with S-1 and Cisplatin for Gastric Cancer with Peritoneal Metastasis

BACKGROUND

Intraperitoneal chemotherapy is promising for gastric cancer with peritoneal metastasis. Although a phase III study failed to show a statistically significant superiority of intraperitoneal paclitaxel combined with S-1 and intravenous paclitaxel, the sensitivity analysis suggested clinical efficacy. Thus, attempts to combine intraperitoneal paclitaxel with other systemic therapies with higher efficacy have been warranted. We sought to explore the efficacy of intraperitoneal paclitaxel with S-1 and cisplatin.

PATIENTS AND METHODS

Gastric cancer patients with peritoneal metastasis were enrolled in the phase II trial. In addition to the established S-1 and cisplatin regimen every 5 weeks, intraperitoneal paclitaxel was administered on days 1, 8, and 22 at a dose of 20 mg/m2. The primary endpoint was overall survival rate at 1 year after treatment initiation. Secondary endpoints were progression-free survival and toxicity.

RESULTS

Fifty-three patients were enrolled and fully evaluated for efficacy and toxicity. The 1-year overall survival rate was 73.6% (95% confidence interval 59.5-83.4%), and the primary endpoint was met. The median survival time was 19.4 months (95% confidence interval, 16.1-24.6 months). The 1-year progression-free survival rate was 49.6% (95% confidence interval, 34.6-62.9%). The incidences of grade 3/4 hematological and non-hematological toxicities were 43% and 47%, respectively. The frequent grade 3/4 toxicities included neutropenia (25%), anemia (30%), diarrhea (13%), and anorexia (17%). Intraperitoneal catheter and implanted port-related complications were observed in four patients. There was one treatment-related death.

CONCLUSIONS

Intraperitoneal paclitaxel combined with S-1 and cisplatin is well tolerated and active in gastric cancer patients with peritoneal metastasis.

Short-term Outcomes of Adjuvant Nivolumab After Neoadjuvant Chemotherapy in Patients With Resected Esophageal Squamous Cell Carcinoma

BACKGROUND/AIM

CheckMate 577 evaluated adjuvant nivolumab therapy after neoadjuvant chemoradiotherapy and surgery for esophageal cancers. However, the efficacy of this treatment in patients who received neoadjuvant chemotherapy remains unknown. This study investigated the short-term outcomes of adjuvant nivolumab therapy in patients with advanced esophageal squamous cell carcinoma post-neoadjuvant chemotherapy.

PATIENTS AND METHODS

Out of 956 patients with thoracic esophageal cancer who underwent radical esophagectomy, 227 who exhibited ypN1-3 after neoadjuvant chemotherapy and surgery were included in this study.

RESULTS

Among 227 patients, 30 received adjuvant nivolumab and 197 received non-nivolumab adjuvant therapy. The nivolumab group displayed a higher number of lymph node metastases compared to the control group. Patients with ypN1-2 tended to have longer recurrence-free survival (RFS) in the nivolumab group than in the non-nivolumab group (p=0.095). In the propensity score-matched cohort, no differences in patient characteristics were observed. Adjuvant nivolumab therapy significantly prolonged RFS in patients who received neoadjuvant chemotherapy (p=0.013). Patients with ypN1-2 in the nivolumab group had significantly longer RFS than their counterparts in the non-nivolumab group (p=0.001), but not in ypN3 (p=0.784). The 1-year postoperative recurrence rates were 59% for the non-nivolumab group and 24% for the nivolumab group (p=0.007). Nivolumab-related adverse events in patients receiving neoadjuvant chemotherapy were mostly consistent across all grades, while the frequency of increased aspartate aminotransferase (AST) levels was relatively higher compared to CheckMate577.

CONCLUSION

Adjuvant nivolumab was more likely to prolong 1-year RFS in patients receiving neoadjuvant chemotherapy, especially in those with ypN1-2, and had acceptable adverse events.

Comparison of the effects of open and laparoscopic approach on body composition in gastrectomy for gastric cancer: A propensity score-matched study

Aim

To compare the effects of open (OG) and laparoscopic gastrectomy (LG) on body composition and muscle strength.

Methods

This study performed a propensity score matching analysis using cases from a large-scale, multicenter, phase III randomized controlled trial concerning oral nutritional supplements after gastrectomy and analyzed both the whole and matched cohorts. Measurements of body composition and hand grip strength (HGS) were performed at baseline (preoperatively) and at 1, 2, 3, 6, and 12 months after gastrectomy.

Results

Of 835 patients, 275 and 560 underwent OG and LG, respectively. Skeletal muscle mass (SMM) and HGS loss were significantly lesser in the LG group than in the OG group. The propensity score-matched analysis, including 120 pairs of patients, confirmed that the % SMM loss values at 1, 2, 3, 6, and 12 POM were -4.5%, -4.0%, -4.7%, -4.6%, and -5.8% in the OG group and -3.0%, -1.9%, -2.4%, -2.2%, and -2.7% in the LG group, respectively. The % SMM loss was significantly lesser in the LG group than in the OG group (repeated measures ANOVA p < 0.001). The HGS loss was non-significantly smaller in the LG group than in the OG group.

Conclusion

Skeletal muscle mass loss was significantly lesser in the LG group than in the OG group in both cohorts, indicating that LG may be more effective than OG for maintaining muscle mass.

Prognostic value of a novel index combining the prognostic nutritional index and D-dimer levels for gastric cancer after gastrectomy

INTRODUCTION

The prognostic nutritional index and D-dimer level are two useful measures for gastric cancer prognosis. Since they each comprise different factors, it is possible to employ a more useful combined indicator. This study therefore aimed to establish a prognostic nutritional index-D score-which combines the prognostic nutritional index and D-dimer level-and validate its usefulness as a prognostic marker.

METHODS

We collected data from 1,218 patients with gastric cancer who had undergone radical gastrectomy (R0) between January 2004 and December 2015. Patients were divided into three prognostic nutritional index-D score groups based on the following criteria: score 2, low prognostic nutritional index (≤46) and high D-dimer levels (>1.0 µg/ml); score 1, either a low prognostic nutritional index or high D-dimer levels; and score 0, no abnormality. We then defined the PNI-D score as low (score 0 or 1) and high (score 2).

RESULTS

The prognostic nutritional index-D score was significantly associated with overall, recurrence-free, and disease-specific survival (all log-rank P<0.0001). The 5-year overall survival rates of the patients with prognostic nutritional index-D scores of low and high were 88.1% and 64.7%, respectively; their 5-year recurrence-free survival rates were 86.7% and 61.3%, respectively; and their 5-year disease-specific survival rates were 99.3% and 76.5%, respectively. Cox multivariate analysis revealed that a high prognostic nutritional index-D score was an independent, statistically significant prognostic factor for poor overall (P=0.01) survival in the patients with gastric cancer.

CONCLUSIONS

The prognostic nutritional index-D is an independent prognostic factor for patients with gastric cancer.

Clinical Impact of Early Tumour Shrinkage in Metastatic or Unresectable Oesophageal Cancer Treated with Pembrolizumab plus Chemotherapy

INTRODUCTION

Metastatic or unresectable locally advanced oesophageal cancer remains a disease with high mortality. More recently, pembrolizumab plus chemotherapy has been indicated as the first-line treatment for those patients, but the predictive factors for treatment efficacy remain controversial. This study investigated the clinical utility of early tumour shrinkage (ETS) and depth of response (DpR) in metastatic or unresectable oesophageal cancer treated with pembrolizumab plus CF therapy.

METHODS

ETS and DpR, defined as the percent decreases at the second evaluation and the percentage of the maximal tumour shrinkage during treatment, were measured in 53 eligible patients. The ETS and DpR cut-off values were 20% and 30%, respectively, based on survival outcomes.

RESULTS

Twenty-seven patients (51%) were treatment-naïve, while 26 (49%) had received any treatment before initiating pembrolizumab plus CF therapy. The median progression-free survival (PFS) and overall survival (OS) for ETS ≥20% and <20% were 12.7 and 5.5 months and 14.4 and 8.2 months, and 12.7 and 4.9 months and 14.4 and 8.0 months for DpR ≥30% and <30%, respectively. ETS <20% showed early tumour growth, whereas ETS ≥20% had a good response rate with sufficient longer response duration. In addition, an ETS cut-off of 20% predicted the best overall response and was not associated with prior treatment. In multivariable analysis, ETS ≥20% and DpR ≥30% were independent factors of longer PFS.

CONCLUSION

Our findings suggest that an ETS is a promising on-treatment marker for early prediction of further sensitivity to pembrolizumab plus CF therapy.

Laparoscopic Gastrectomy for Advanced Gastric Cancer

BACKGROUND

Application of laparoscopic gastrectomy (LG) to advanced gastric cancer is still controversial due to lack of sufficient surgical and oncological outcomes. The purpose of this study was to elucidate the feasibility of LG for advanced gastric cancer by multicenter prospective cohort study.

METHODS

A total of 98 patients with clinical stage II or III gastric cancer from 8 institutes were analyzed in this study. The primary endpoint was incidence of severe postoperative complications of Clavien-Dindo classification grade Ⅲa or higher.

RESULTS

Sixty-six patients underwent laparoscopic distal gastrectomy (LDG), 10 patients laparoscopic proximal gastrectomy (LPG), 21 patients laparoscopic total gastrectomy (LTG), and 1 patient received gastro-jejunostomy. Seven patients had positive lavage cytology (CY1) and R0 rate was 90.8%. Three patients (3.1%) required conversion to open surgery. The incidence of overall postoperative complications and severe postoperative complications were 17.3% and 9.2%, respectively, those were comparable to the data of open surgery for advanced gastric cancer previously published. By surgical procedure, the incidence of severe postoperative complications of LDG, LPG, and LTG were 4.6, 0, and 28.6% and the rate of severe anastomotic leakage of LDG, LPG, and LTG were 0, 0, and 9.5%, respectively. Total gastrectomy was an only independent risk factor of severe postoperative complications in LG for advanced gastric cancer (odds ratio 8.75; 95% confidence interval 1.70-56.69, P = .0092).

DISCUSSION

The incidence of severe postoperative complications after LG performed by qualified surgeons was acceptable even in cases of advanced gastric cancer; however, careful attention is required to adopt LTG. (UMIN000025733).

Early detection of brain metastases and appropriate local therapy followed by systemic chemotherapy may improve the prognosis of gastric cancer

Brain metastases develop in 0.5-0.7% of patients with gastric/gastroesophageal junction (G/GEJ) cancer. Although rare, brain metastasis is often identified when the patient is already symptomatic; hence prognosis is poor. Given the therapeutic developments for G/GEJ cancer, overall survival is prolonged, thereby the incidence of brain metastases is predicted to increase. We retrospectively surveyed the rate of brain metastasis among 1257 patients diagnosed with G/GEJ cancer who received chemotherapy between January 2011 and April 2021. We investigated the time of onset of brain metastasis, treatments administered, and impact of the metastasis on the overall treatment course and prognosis. Of the 741 patients included in the analysis, brain metastasis was confirmed in 16 (2.2%). The median survival time (MST) from G/GEJ cancer diagnosis was 14.9 months in patients with brain metastasis detected during the treatment period, and the MST from the diagnosis of brain metastasis was 2.8 months. Patients who received chemotherapy exhibited prolonged survival compared with those who did not (12.4 months vs 1.0 months, p < 0.001). Our findings suggest that the early detection of brain metastases and local therapy for poor responders to chemotherapy enable the continuation of chemotherapy and prolong survival.

Clinicopathological characteristics and survival outcomes in patients with advanced esophageal squamous cell carcinoma who were intraoperatively diagnosed non-curative

INTRODUCTION

Curative esophagectomy is not always possible in patients with locally advanced esophageal cancer. However, few studies have investigated patients who underwent non-curative surgery with intraoperative judgment. This study aimed to investigate patient characteristics and clinical outcomes for patients undergoing non-curative surgery and compare them between non-resectional and non-radical surgery.

METHODS

Among 989 consecutive patients with thoracic esophageal squamous cell carcinoma (ESCC) who were preoperatively expected for curative esophagectomy, 66 who were eligible for non-curative surgery were included in this study.

RESULTS

Intraoperative diagnosis of T4b accounted for 93% of the reasons for the failure of curative surgery. In those patients, esophageal cancer locally invaded into the aortobronchial constriction (70%), trachea (25%), or pulmonary vein (5%). LN metastasis mainly invaded into the trachea (50%), or bronchus (28%).The overall survival of patients with non-curative surgery was 51.5%, 25.7%, and 10.4% at 6, 12, and 24 months after surgery, respectively. Although there were no differences in preoperative patient characteristics between non-resectional and non-radical surgery, distant metastasis, especially pleural dissemination, was significantly observed in T4b patients due to esophageal cancer with non-radical surgery than those with non-resectional surgery (35% vs. 15%, P=0.002). Even in patients with non-curative surgery, R1 resection and postoperative CRT were identified as independent factors for survival 1 year after surgery (P=0.047, and 0.019).

CONCLUSIONS

T4b tumor located in aortobronchial constriction or trachea/bronchus makes it difficult to diagnose whether it is resectable or unresectable. Moreover, surgical procedures and perioperative treatment were deeply associated with the clinical outcomes.

Adjuvant Chemotherapy With S-1 Plus Docetaxel Versus S-1 Plus Oxaliplatin in Stage III Gastric Cancer

BACKGROUND/AIM

The Japanese Gastric Cancer Treatment Guidelines recommend doublet chemotherapy (S-1 plus another chemotherapy) over S-1 alone for patients with pStage III gastric cancer who underwent radical gastrectomy. However, no consensus exists on adjuvant regimens for patients with pStage III gastric cancer. Therefore, we conducted a comparative study to evaluate the tolerability, safety, and survival outcomes of docetaxel plus S-1 (DS) and S-1 plus oxaliplatin (SOX) therapies as adjuvant chemotherapy for patients with pStage III gastric cancer.

PATIENTS AND METHODS

We retrospectively collected data from consecutive patients with gastric cancer who underwent gastrectomy and received DS or SOX therapies postoperatively at the Osaka International Cancer Institute between December 2016 and December 2021. We conducted a propensity score matching analysis to balance clinical backgrounds.

RESULTS

Eighty patients who met the eligibility criteria were analyzed. After matching, 40 patients were included in the study (20 each in the DS and SOX groups). No significant adverse events were observed. The mean ratios of the delivered dose to the planned dose were 74.1% and 86.6% for S-1 and docetaxel in the DS group, respectively, and 75.8% and 76.9% for S-1 and oxaliplatin in the SOX group, respectively. No significant differences were found in recurrence-free and overall survival between the DS and SOX groups (p=0.688 and p=0.772, respectively).

CONCLUSION

DS and SOX therapies as adjuvants were safe and manageable for patients with pStage III gastric cancer who underwent radical gastrectomy. No significant differences were found in prognosis between the two therapies.

The receding contact line cools down during dynamic wetting

When a contact line (CL)-where a liquid-vapor interface meets a substrate-is put into motion, it is well known that the contact angle differs between advancing and receding CLs. Using non-equilibrium molecular dynamics simulations, we reveal another intriguing distinction between advancing and receding CLs: while temperature increases at an advancing CL-as expected from viscous dissipation, we show that temperature can drop at a receding CL. Detailed quantitative analysis based on the macroscopic energy balance around the dynamic CL showed that the internal energy change of the fluid due to the change of the potential field along the pathline out of the solid-liquid interface induced a remarkable temperature drop around the receding CL, in a manner similar to latent heat upon phase changes. This result provides new insights for modeling the dynamic CL, and the framework for heat transport analysis introduced here can be applied to a wide range of nanofluidic systems.

Randomized controlled phase III trial to investigate superiority of robot-assisted gastrectomy over laparoscopic gastrectomy for clinical stage T1-4aN0-3 gastric cancer patients (JCOG1907, MONA LISA study): a study protocol

BACKGROUND

Laparoscopic gastrectomy (LG) is considered a standard treatment for clinical stage I gastric cancer. Nevertheless, LG has some drawbacks, such as motion restriction and difficulties in spatial perception. Robot-assisted gastrectomy (RG) overcomes these drawbacks by using articulated forceps, tremor-filtering capability, and high-resolution three-dimensional imaging, and it is expected to enable more precise and safer procedures than LG for gastric cancer. However, robust evidence based on a large-scale randomized study is lacking.

METHODS

We are performing a randomized controlled phase III study to investigate the superiority of RG over LG for clinical T1-2N0-2 gastric cancer in terms of safety. In total, 1,040 patients are planned to be enrolled from 46 Japanese institutions over 5 years. The primary endpoint is the incidence of postoperative intra-abdominal infectious complications, including anastomotic leakage, pancreatic fistula, and intra-abdominal abscess of Clavien-Dindo (CD) grade ≥ II. The secondary endpoints are the incidence of all CD grade ≥ II and ≥ IIIA postoperative complications, the incidence of CD grade ≥ IIIA postoperative intra-abdominal infectious complications, relapse-free survival, overall survival, the proportion of RG completion, the proportion of LG completion, the proportion of conversion to open surgery, the proportion of operation-related death, and short-term surgical outcomes. The Japan Clinical Oncology Group Protocol Review Committee approved this study protocol in January 2020. Approval from the institutional review board was obtained before starting patient enrollment in each institution. Patient enrollment began in March 2020. We revised the protocol to expand the eligibility criteria to T1-4aN0-3 in July 2022 based on the results of randomized trials of LG demonstrating non-inferiority of LG to open surgery for survival outcomes in advanced gastric cancer.

DISCUSSION

This is the first multicenter randomized controlled trial to confirm the superiority of RG over LG in terms of safety. This study will demonstrate whether RG is superior for gastric cancer.

TRIAL REGISTRATION

The protocol of JCOG1907 was registered in the UMIN Clinical Trials Registry as UMIN000039825 ( http://www.umin.ac.jp/ctr/index.htm ). Date of Registration: March 16, 2020. Date of First Participant Enrollment: April 1, 2020.

Clinical Impact of Enhanced Recovery After Esophagectomy in Patients With Esophageal Cancer

BACKGROUND/AIM

The enhanced recovery after surgery (ERAS) program is expected to improve perioperative outcomes in patients with esophageal cancer. However, how ERAS impacts the postoperative body composition and factors related to compliance rate of ERAS have not been fully investigated.

PATIENTS AND METHODS

The study included 252 consecutive patients with thoracic esophageal cancer who underwent minimally invasive esophagectomy. We compared the postoperative outcomes including body composition between the old perioperative program and the new one that aimed to shorten postoperative length of stay (LOS). Compliance-related clinical factors were also examined.

RESULTS

From 252 patients, 129 underwent the old program and 123 the new program. Postoperative LOS, postoperative complications, and hospital costs were reduced with the new program. Body weight loss was significantly improved with the new program at discharge and 3-months after esophagectomy (94.9% vs. 96.6%, p=0.013, 89.5% vs. 91.1%, p=0.028, respectively). Patients in the new program had better body composition at discharge than those in the old program [body fat mass (91.6% vs. 94.1%), lean body mass (95.2% vs. 97.2), and skeletal muscle mass (95.3% vs. 97.0%)]. Major reasons for incompliance were dysphagia, pneumonia, and anastomotic leakage. Multivariate analysis revealed that age ≥70 years at surgery and sex (male) were independent risk factors for incompliance with the postoperative program.

CONCLUSION

The new ERAS program aimed to shorten postoperative LOS had clinical benefits in body composition early after esophagectomy. Personalized ERAS programs based on age might lead to better postoperative outcomes because of low compliance rates for older patients.

Equilibrium molecular dynamics evaluation of the solid-liquid friction coefficient: Role of timescales

Solid-liquid friction plays a key role in nanofluidic systems. Following the pioneering work of Bocquet and Barrat, who proposed to extract the friction coefficient (FC) from the plateau of the Green-Kubo (GK) integral of the solid-liquid shear force autocorrelation, the so-called plateau problem has been identified when applying the method to finite-sized molecular dynamics simulations, e.g., with a liquid confined between parallel solid walls. A variety of approaches have been developed to overcome this problem. Here, we propose another method that is easy to implement, makes no assumptions about the time dependence of the friction kernel, does not require the hydrodynamic system width as an input, and is applicable to a wide range of interfaces. In this method, the FC is evaluated by fitting the GK integral for the timescale range where it slowly decays with time. The fitting function was derived based on an analytical solution of the hydrodynamics equations [Oga et al., Phys. Rev. Res. 3, L032019 (2021)], assuming that the timescales related to the friction kernel and the bulk viscous dissipation can be separated. By comparing the results with those of other GK-based methods and non-equilibrium molecular dynamics, we show that the FC is extracted with excellent accuracy by the present method, even in wettability regimes where other GK-based methods suffer from the plateau problem. Finally, the method is also applicable to grooved solid walls, where the GK integral displays complex behavior at short times.

Tumor Deposit Is an Independent Factor Predicting Early Recurrence and Poor Prognosis in Gastric Cancer

BACKGROUND

Accurate prognostic estimation is crucial; however, the prognostic value of tumor deposits in gastric cancer remains controversial. This study aimed to investigate their prognostic significance.

METHODS

Clinicopathological and prognostic data of 1012 gastric cancer patients who underwent R0 or R1 surgery from 2010 to 2017 at the Osaka International Cancer Institute were retrospectively reviewed.

RESULTS

Overall, 6.3% patients had tumor deposits, which were associated with Borrmann type, surgical procedure, type of gastrectomy, extent of lymphadenectomy, tumor size, histology, pT, pN, pM, pStage, lymphatic invasion, vascular invasion, preoperative chemotherapy, and postoperative chemotherapy. Tumor deposit-positive patients had worse 5-year disease-free survival (32.60% vs. 92.45%) and overall survival (41.22% vs. 89.37%) than tumor deposit-negative patients. Subgroup analysis regarding pStage II-III also showed significant differences between patients with and without tumor deposits for 5-year disease-free survival (34.15% vs. 80.98%) and overall survival (43.17% vs. 75.78%). Multivariable analysis showed that older age, undifferentiated histology, deeper tumor invasion, lymph node metastasis, distant metastasis, and presence of tumor deposits were significantly correlated with early tumor recurrence and shorter survival time; these factors were identified as independent prognostic factors. The 5-year disease-free survival of tumor deposit-positive patients was significantly worse than that of patients in the pStage III group and comparable to that of patients in the pT4, pN3, and pM1 groups. The 5-year overall survival of tumor deposit-positive patients was comparable to that of the pT4, pN3, pM1, and pStage III groups.

CONCLUSIONS

Tumor deposits are strong and independent predictors of tumor recurrence and poor survival.

Clinical Impact of Metastatic Lymph Node Size on Therapeutic Effect and Prognosis in Patients with Esophageal Squamous Cell Carcinoma Who Underwent Preoperative Chemotherapy Followed by Esophagectomy

BACKGROUND

Pretreatment metastatic lymph node (LN) size has been reported to be associated with prognosis in esophageal squamous cell carcinoma (ESCC). However, its relationship with response to preoperative chemotherapy or prognosis has not been clarified. We investigated the relationship between metastatic LN size and response to preoperative treatment, and prognosis in patients with metastatic esophageal cancer who underwent surgery.

PATIENTS AND METHODS

A total of 212 clinically node-positive patients who underwent preoperative chemotherapy followed by esophagectomy for ESCC were enrolled. Patients were stratified into three groups on the basis of the length of the short axis of the largest LN in pretreatment computed tomography images: < 10 mm (group A), 10-19 mm (group B), and ≥ 20 mm (group C).

RESULTS

Group A had 90 patients (42%), group B had 103 patients (49%), and group C had 19 patients (9%). Group C had significantly lower percent reduction in total metastatic LN size than groups A and B (22.5% versus 35.7%, P = 0.037). Group C had significantly more metastatic LNs based on histological examination than groups A and B (10.1 versus 2.4, P < 0.001). Group C patients whose LNs responded had significantly fewer metastatic LNs than nonresponders (5.1 versus 11.9, P = 0.042). Group C had significantly poorer overall survival than groups A and B (3-year survival, 25.4% versus 67.3%, P < 0.001). However, group C patients whose LNs responded had better survival than nonresponders (3-year survival, 57.1% versus 0%, P = 0.008).

CONCLUSIONS

Patients with large metastatic LNs have poor response and poor prognosis. However, if a response is obtained, long-term survival can be expected.

The utility of bile juice culture analysis for the management of postoperative infection after pancreaticoduodenectomy

BACKGROUND

Surgical site infections are common after pancreaticoduodenectomy. Our institution routinely performs intraoperative bile culture with pancreaticoduodenectomy. Herein we examined whether antibiotic selection based on bile culture analysis reduced the surgical site infection risk after pancreaticoduodenectomy.

METHODS

A total of 349 patients underwent pancreaticoduodenectomy with intraoperative bile cultures in our institution between 2008 and 2019. Patients were categorized into "group A" (196 patients who underwent pancreaticoduodenectomy between 2008 and 2013) or "group B" (153 patients who underwent pancreaticoduodenectomy between 2018 and 2019). Group A received cefazoline perioperatively and for 2 days postoperatively, whereas group B received piperacillin-tazobactam instead based on the bile culture findings in group A.

RESULTS

In group A, 91 (46.4%) intraoperative bile cultures were positive, and surgical site infections occurred in 61 patients (31.1%). A total of 32 patients had both positive bile culture and surgical site infection, of whom 23 (71.9%) exhibited the same microorganisms in the biliary and surgical site infection cultures. Due to the common finding of cefazoline-resistant Enterococcus spp. and Enterobacter spp. in group A, group B received piperacillin-tazobactam. Surgical site infection incidence in group B was 18.3% (n = 28), which was significantly lower than in group A (P = .006). Cefazoline-resistant Enterococcus spp. and Enterobacter spp., respectively, were cultured in 69.8% and 24.3% of patients with preoperative biliary drainage, compared with 32.2% and 9.7% of patients without preoperative biliary drainage.

CONCLUSION

The perioperative selection of antibiotics based on bile culture findings at pancreaticoduodenectomy can reduce the incidence of surgical site infection.

Plasma trough concentration of imatinib and its effect on therapeutic efficacy and adverse events in Japanese patients with GIST

BACKGROUND

Imatinib mesylate (IM) is the standard chemotherapy for patients with gastrointestinal stromal tumors (GISTs) and has a favorable safety profile. Pharmacokinetics (PK), such as plasma trough concentration (Cmin), varies among patients, requiring the need for therapeutic drug monitoring (TDM) during IM administration. Despite some reports from overseas, the relationship between Cmin, adverse events (AEs), and treatment efficacy in Japanese patients with GIST has still been lacking. This study aimed to investigate the relationship between IM plasma concentration and AEs in Japanese patients with GISTs.

METHODS

This retrospective study analyzed the data of 83 patients who underwent IM treatment for GISTs at our institution between May 2002 and September 2021.

RESULTS

The IM Cmin was associated with any grade of AEs (with AEs vs. without AEs = 1294 (260-4075) vs. 857 (163-1886) ng/mL, P < 0.001), edema (with edema vs. without edema = 1278 (634-4075) vs. 1036 (163-4069) ng/mL, P = 0.017), and fatigue (with fatigue vs. without fatigue = 1373 (634-4069) vs. 1046 (163-4075) ng/mL, P = 0.044). Moreover, a Cmin ≥ 1283 ng/mL was a risk factor for severe AEs. The median progression-free survival (PFS) was 3.04 years in the lowest Cmin tertile (T1, < 917 ng/mL) compared with 5.90 years for T2 and T3 (P = 0.010).

CONCLUSION

Edema and fatigue are potentially associated with IM plasma trough concentrations of ≥ 1283 ng/mL in Japanese patients with GISTs. Further, maintaining an IM plasma trough concentration above 917 ng/mL may improve PFS.

Combined intraperitoneal and systemic chemotherapy as adjuvant or perioperative chemotherapy for patients with type 4 scirrhous gastric cancer: PHOENIX-GC2 trial

TPS477

Background: Despite recent progress in adjuvant and perioperative chemotherapy, the prognosis of patients with type 4 scirrhous gastric cancer remains poor due to a high risk of peritoneal metastasis. We have previously developed combination chemotherapy regimens of intraperitoneal (IP) paclitaxel (PTX) and systemic chemotherapy, and promising clinical efficacy was reported in gastric cancer with peritoneal metastasis. Herein, a multicenter, open-label, randomized, phase III study is proposed to verify the efficacy of IP PTX to prevent peritoneal recurrence. Methods: Gastric cancer patients with type 4 tumors and without apparent distant metastasis, including peritoneal metastasis, will be randomized for standard systemic chemotherapy or combined IP and systemic chemotherapy based on peritoneal lavage cytology findings. Those with negative peritoneal cytology will receive radical gastrectomy and adjuvant chemotherapy of S-1 plus docetaxel (control arm), or S-1 plus intravenous and IP PTX (experimental arm). Those with positive peritoneal cytology will receive three courses of S-1 plus oxaliplatin (control arm), or S-1 plus oxaliplatin and IP PTX (experimental arm). Subsequently, they undergo gastrectomy and receive postoperative chemotherapy of S-1 plus docetaxel (control arm), or S-1 plus intravenous and IP PTX (experimental arm). The primary endpoint is disease free survival after a 3-year follow-up period. Secondary endpoints are overall survival, survival without peritoneal metastasis, safety, completion rate, curative resection rate, and histological response of preoperative chemotherapy. A total of 300 patients are to be enrolled from 40 hospitals throughout Japan. Clinical trial information: jRCT2031200087 .

Single-arm phase II trial to evaluate the safety of laparoscopic/robotic total gastrectomy with spleen-preserving splenic hilar dissection for locally advanced proximal gastric cancer that invades the greater curvature: JCOG1809

TPS479

Background: The standard treatment for locally advanced proximal gastric cancer invading the greater curvature is “open total gastrectomy combined with splenectomy” (OTG+S) aiming for whole clearance of the splenic hilar lymph nodes. However, its pertinent postoperative severe complication (e.g. pancreatic fistula) is problematic. An objective of this study is to evaluate the safety of “laparoscopic or robotic total gastrectomy with spleen-preserving splenic hilar dissection” (LRSHD) as a new treatment option which has a potential to reduce surgical morbidity, subsequently to replace the current standard treatment, OTG+S. Methods: This is a multicenter single-arm phase II trial. The main eligibility criteria are as follows; clinical T2-4a resectable locally advanced proximal gastric adenocarcinoma that invades the greater curvature; without obvious lymph node metastasis at the splenic hilum nor direct invasion to the spleen/splenogastric ligament. Protocol treatment is laparoscopic or robotic total gastrectomy with splenic hilar lymph node dissection (D2 + No.10 lymphadenectomy according to the Japanese guidelines) in which the spleen is preserved with skeletonizing the splenic vessels. Quality control of surgery is assured by surgeon’s qualification and central peer review of intraoperative photo at the splenic hilum after dissection. The primary endpoint is the proportion of postoperative pancreatic fistula and/or intra-abdominal abscess formation with Clavien-Dindo Grade III or higher (within 30 days after surgery). Secondary endpoints are intraoperative blood loss, operation time, mortality, overall postoperative complication, number of yield splenic hilar nodes, number of metastatic splenic hilar nodes, conversion to splenectomy, conversion to laparotomy, relapse-free survival, and overall survival. Sample size was set as 85 patients to obtain 80% power considering that 15% of patients are judged as unresectable intraoperatively, with the hypothesis that the primary endpoint would have an expected value of 7% and a threshold value of 16% in one-sided alpha of 0.1. Planned accrual period is 5 years. The accrual began in August 2019. As of August 2022, 53 of the planned 85 patients (62.4%) have been enrolled. When the safety of LRSHD is proved by this study, a non-inferiority phase III trial will be consequently launched. Clinical trial registry number: UMIN000037580. Clinical trial information: UMIN000037580 .

Long-term outcomes after laparoscopy-assisted total or proximal gastrectomy with nodal dissection for clinical stage I gastric cancer: Japan Clinical Oncology Group study (JCOG1401)

305

Background: JCOG0912 supports the non-inferiority of laparoscopy-assisted distal gastrectomy (LADG) compared with open distal gastrectomy (ODG) for clinical stage I gastric cancer relapse-free survival (RFS), suggesting that LADG should be considered a standard treatment option when performed by experienced surgeons. No prospective study evaluating laparoscopy-assisted total gastrectomy (LATG) and laparoscopy-assisted proximal gastrectomy (LAPG) has been completed in terms of both safety and long-term survival. Considering that the results of the phase III trial to evaluate the long-term outcome of LADG (JCOG0912) could guarantee that of LATG/LAPG, we conducted a single-arm confirmatory trial (JCOG1401) to evaluate the safety of LATG/LAPG for clinical stage I proximal gastric cancer and JCOG1401 confirmed the safety of LATG/LAPG. Long-term outcomes as the secondary endpoints of this study are reported here after 5-year follow-up period. Methods: Laparoscopic operators were limited to credentialed surgeons. The extent of nodal dissection was selected based on the Gastric Cancer Treatment Guidelines in Japan. The primary endpoint was the proportion of grade 2 (CTCAE ver. 4.0) or greater esophageal anastomotic leak. The sample size was determined to be 245 considering a threshold of 8% and expected value of 3% with a one-sided alpha error of 2.5% and statistical power of 90%. The secondary endpoints were overall survival (OS) and RFS. Results: Between April 2015 and February 2017, 245 patients were enrolled. Among them, 1 patient was excluded from safety analysis due to ineligible. LATG/LAPG was performed in 195/49. 170/47/17/8/2 patients had pStage IA/IB/II/IIIA/IIIB disease and 190/31/15/8 patients had pT1/T2/T3/T4 disease, respectively. Grade 2 or greater esophageal anastomotic leak was 2.5% (6/244) (95% CI 0.9-5.3), as previously reported. 5-year OS was 91.2% (95% CI 86.9-94.2). 5-year RFS was 90.0% (95% CI 85.5-93.2). Among 22 deaths, 14 patients died without recurrence and 8 patients died with recurrence. Twelve recurrences were observed in 5/2/4/1 patients for pT1/T2/T3/T4. The sites of recurrence were peritoneal metastasis in 2 cases, hematogenous metastasis in 9 cases (liver: 6, bone: 2, lung: 1), and other in 1 case. Conclusions: The long-term outcomes of LATG/LAPG for Stage I gastric cancer patients were excellent and seem comparable to those of open procedures. Similar to JCOG0912, JCOG1401 guarantee the long-term survival of LATG/LAPG. Clinical trial information: UMIN000017155 .

DUPAN-II normalisation as a biological indicator during preoperative chemoradiation therapy for resectable and borderline resectable pancreatic cancer

BACKGROUND

Duke pancreatic mono-clonal antigen type 2 (DUPAN-II) is a famous tumour maker for pancreatic cancer (PC) as well as carbohydrate antigen 19-9 (CA19-9). We evaluated the clinical implications of DUPAN-II levels as a biological indicator for PC during preoperative chemoradiation therapy (CRT).

METHODS

This retrospective analysis included data from 221 consecutive patients with resectable and borderline resectable PC at diagnosis who underwent preoperative CRT between 2008 and 2017. We focused on 73 patients with elevated pre-CRT DUPAN-II levels (> 230 U/mL; more than 1.5 times the cut-off value for the normal range). Pre- and post-CRT DUPAN-II levels and the changes in DUPAN-II ratio were measured.

RESULTS

Univariate analysis identified normalisation of DUPAN-II levels after CRT as a significant prognostic factor (hazard ratio [HR] = 2.06, confidence interval [CI] = 1.03-4.24, p = 0.042). Total normalisation ratio was 49% (n = 36). Overall survival (OS) in patients with normalised DUPAN-II levels was significantly longer than that in 73 patients with elevated levels (5-year survival, 55% vs. 21%, p = 0.032) and in 60 patients who underwent tumour resection (5-year survival, 59% vs. 26%, p = 0.039).

CONCLUSION

Normalisation of DUPAN-II levels during preoperative CRT was a significant prognostic factor and could be an indicator to monitor treatment efficacy and predict patient prognosis.

Establishment of preanalytical conditions for microRNA profile analysis of clinical plasma samples

The relationship between the expression of microRNAs (miRNAs) in blood and a variety of diseases has been investigated. MiRNA-based liquid biopsy has attracted much attention, and cancer-specific miRNAs have been reported. However, the results of analyses of the expression of these miRNAs vary among studies. The reproduction of results regarding miRNA expression levels could be difficult if there are differences in the data acquisition process. Previous studies have shown that the anticoagulant type used during plasma preparation and sample storage conditions could contribute to differences in measured miRNA levels. Thus, the impact of these preanalytical conditions on comprehensive miRNA expression profiles was examined. First, the miRNA expression profiles of samples obtained from healthy volunteers were analyzed using next-generation sequencing. Based on an analysis of the library concentration, human genome identification rate, ratio of unique sequences and expression profiles, the optimal preanalytical conditions for obtaining highly reproducible miRNA expression profiles were established. The optimal preanalytical conditions were as follows: ethylenediaminetetraacetic acid (EDTA) as the anticoagulant, whole-blood storage at room temperature within 6 hours, and plasma storage at 4°C or -20°C within 30 days. Next, plasma samples were collected from 60 cancer patients (3 facilities × 20 patients/facility), and miRNA expression profiles were analyzed. There were no significant differences in measurements except in the expression of erythrocyte-derived hsa-miR-451a. However, the variation in hsa-miR-451a levels was smaller among facilities than among individuals. This finding suggests that samples obtained from the same facility could show significantly different degrees of hemolysis across individuals. We found that the standardization of anticoagulant use and storage conditions contributed to reducing the variation in sample quality across facilities. The findings from this study could be useful in developing protocols for collecting samples from multiple facilities for cancer screening tests.

[Three Cases Who Underwent Laparoscopic Radical Resection after Preoperative Therapy for Massive Rectal GIST]

The gastrointestinal stromal tumor(GIST)guidelines state that the use of neoadjuvant chemotherapy(NAC)for curable GIST is not apparent. However, NAC is performed for massive rectal GIST at our hospital to reduce surgical invasion and improve surgical results. The cases were a 39-year-old man, a 48-year-old man, and a 78-year-old man. The site was Rb in all cases, and the maximum diameters at the rectal GIST diagnosis were respectively 70 mm, 75 mm, and 60 mm, which were massive tumors. Imatinib mesylate(imatinib)was started as NAC. The duration of NAC was respectively 6, 11, and 12 months. The maximum tumor diameter on preoperative CT was smaller than before NAC, and the average reduction rate was 23%. Two cases underwent laparoscopic abdominal perineal resection, and 1 underwent laparoscopic ultra-low anterior resection and ileostomy. No perioperative complications of Clavien-Dindo classification Grade Ⅱ or higher were unsettled. All patients were in the high risk group and received imatinib as postoperative adjuvant chemotherapy. Currently, respectively 2 years and 3 months, 1 year and 2 months, and 1 year after surgery, all are alive without recurrence. NAC with imatinib has contributed to minimally invasive and radical surgery for giant rectal GIST.

Underwater EMR for the diagnosis of diffuse infiltrative gastric cancer

Video 1Underwater EMR for establishing diagnosis of diffuse infiltrative gastric cancer.

Modified Collard technique is more effective than circular stapled for cervical esophagogastric anastomosis in prevention of anastomotic stricture: a propensity score-matched study

The anastomotic technique after esophagectomy is of great interest in the prevention of anastomotic complications that adversely affect postoperative recovery. This study aimed to compare the clinical outcomes of modified Collard (MC) and circular stapled (CS) anastomoses after esophagectomy. A total of 504 consecutive patients with thoracic esophageal cancer who underwent esophagectomy and cervical esophagogastric CS or MC anastomosis from January 2013 to December 2019 were enrolled. Out of 504 patients, 134 and 370 underwent CS and MC anastomoses. The frequency of anastomotic leakage and stricture was significantly lesser in the MC group than in the CS group (3.0 vs. 10.5%, P = 0.0014 and 11.1 vs. 34.3%, P &lt; 0.001, respectively). CS anastomosis was an independent risk factor for anastomotic stricture (odds ratio, 4.89; P &lt; 0.001). Oral intake was significantly higher in the group without anastomotic stricture than in the group with anastomotic stricture at 2, 3, and 6 months postoperatively (P &lt; 0.001, P = 0.013, and P &lt; 0.001, respectively). The percentage body weight loss (%BWL) was −12.2% in the group with anastomotic stricture and −7.5% in the group without anastomotic stricture at 3 months postoperatively (P = 0.0012). Anastomotic stricture was an independent factor associated with %BWL (odds ratio, 4.86; P = 0.010). Propensity score-matched analysis, which included 88 pairs of patients, confirmed a significantly lower anastomotic stricture rate in the MC group than in the CS group (10.2 vs. 35.2%, P &lt; 0.001). MC anastomosis is better than CS anastomosis for reducing the frequency of anastomotic stricture, which may be useful for maintaining early postoperative nutritional status.

Safety and efficacy of preoperative indocyanine green fluorescence marking in laparoscopic gastrectomy for proximal gastric and esophagogastric junction adenocarcinoma (ICG MAP study)

PURPOSE

The incidence of adenocarcinoma of the esophagogastric junction (AEG) and proximal gastric cancer (PGC) is rising worldwide. Recently, the use of indocyanine green (ICG) tracer-guided surgery has been reported; however, its efficacy for total/proximal gastrectomy has not been clarified. We evaluated the feasibility and safety of ICG fluorescent marking for tumor localization in AEG/PGC treatment by laparoscopic surgery.

METHODS

We enrolled patients with AEG/PGC from October 2016 to March 2019 from a prospectively registered database. On the day before surgery, ICG markings were made at four locations just at the edge of the tumor by gastrointestinal fiberscope examination. Surgery was performed while viewing the fluorescence image of ICG, and the proximal portions of the esophagus and the distal portion of the stomach were resected at the edge of the area where ICG had spread.

RESULTS

We enrolled 130 patients with AEG/PGC. Overall, 107 patients were eventually included in the study: AEG n = 64 (60%) and PGC n = 43 (40%). ICG markings were detected intraoperatively in all cases, and cancer invasion into the resection lines of the esophagus and stomach, performed based on ICG fluorescence images, was negative in all cases. The median visible range of ICG fluorescence was 22.5 mm. ICG diffusion expanded 20 mm proximal for AEG. There were no adverse events associated with endoscopic ICG injection.

CONCLUSION

ICG fluorescence imaging is feasible and safe and can potentially be used as a tumor-marking agent for determining the surgical resection line for total/proximal gastrectomy in AEG and PGC treatment.

Recurrence Pattern Comparing Preoperative Chemoradiotherapy and Preoperative Chemotherapy with Docetaxel plus 5-Fluorouracil and Cisplatin for Advanced Esophageal Cancer

BACKGROUND

Preoperative chemoradiation therapy (CRT) or chemotherapy (CT) followed by surgery is currently being administered for advanced esophageal cancer. However, few studies have directly compared CRT and CT for treating locally advanced esophageal carcinoma. This study aimed to assess postoperative recurrence patterns and post-recurrence outcomes in patients with radical esophagectomy after CRT or triplet CT regimen with docetaxel, cisplatin, and 5-fluorouracil (DCF).

METHODS

This study included 325 consecutive patients with thoracic esophageal cancer who received preoperative CRT or DCF followed by curative esophagectomy between January 2010 and December 2019. We compared recurrence patterns after surgery and post-recurrence treatments between CRT and DCF. Locoregional recurrence was defined as recurrences at the primary tumor site or regional lymph nodes. Distant recurrence was defined as non-regional lymph node recurrences, systemic metastases, malignant pleural effusions, or peritoneal metastases.

RESULTS

Among 325 patients, 74 received preoperative CF+RT and 251 received preoperative DCF. A propensity score-matched cohort of 53 with CRT and 53 with DCF was included. CRT patients had tumors located in the upper esophagus and had more advanced cancer than DCF patients; however, no differences in patient characteristics were observed in the matched cohort. CRT patients had better histopathological responses and control of locoregional recurrence than DCF patients. On the other hand, distant recurrence, especially in non-regional lymph node, lung, and pleural dissemination, significantly developed more frequently in CRT patients. Furthermore, CRT patients may have received insufficient post-recurrence treatment owing to fewer treatment options. Therefore, although there was no difference in recurrence rate in the two groups, CRT patients had significantly poorer post-recurrence survival than DCF patients Conclusions. Preoperative DCF could reduce distant recurrence after surgery compared to preoperative CRT. The differences in recurrence patterns can be related to the selection of post-recurrence treatment and their prognosis after recurrence.

Laparoscopic Proximal Gastrectomy with Novel Valvuloplastic Esophagogastrostomy vs. Laparoscopic Total Gastrectomy for Stage I Gastric Cancer: a Propensity Score Matching Analysis

BACKGROUND

Laparoscopic total gastrectomy for early proximal gastric cancer is widely performed. Recently, the number of laparoscopic proximal gastrectomies performed, a surgery limited to early proximal gastric cancer, has gradually increased. However, evidence for the long-term outcomes of laparoscopic total gastrectomy and laparoscopic proximal gastrectomy is insufficient. Therefore, this study aimed to clarify and compare the long-term outcomes of laparoscopic total gastrectomy and laparoscopic proximal gastrectomy with novel valvuloplastic esophagogastrostomy for treatment of clinical stage I proximal gastric cancer.

METHODS

This study included 111 patients who underwent laparoscopic total gastrectomy or laparoscopic proximal gastrectomy for the treatment of upper third clinical stage I gastric cancer between April 2004 and December 2017. After adjusting for propensity score matching analysis, we compared the postoperative complications, nutritional status, and long-term outcomes between the two groups.

RESULTS

After matching the inclusion criteria, 56 patients (28 in each group) were enrolled. No significant differences were noted in the postoperative complications between the two groups. While laparoscopic proximal gastrectomy was associated with lower albumin levels, lower body weight loss was seen by 1 year after surgery and higher hemoglobin levels by 1, 2, and 3 years after surgery. No significant differences were observed in the 3-year overall survival and 3-year recurrence-free survival between the laparoscopic total gastrectomy and laparoscopic proximal gastrectomy groups (P = 0.74 and 0.72, respectively).

CONCLUSION

Laparoscopic proximal gastrectomy and laparoscopic total gastrectomy for patients with upper third clinical stage I gastric cancer are feasible as regards its safety and outcomes.

The DOLFIN method: a novel laparoscopic Billroth-I gastroduodenostomy for gastric cancer with duodenal invasion

BACKGROUND

Laparoscopic Billroth-I gastroduodenostomy using a delta-shaped anastomosis is safe and feasible. However, it is often difficult to perform in patients who have a short posterior wall of the duodenum. Thus, we have developed a new method named duodenal overlap functional anastomosis with linear stapler (DOLFIN). We hereby report the technical details of the new method and our preliminary experience performing it.

METHODS

After the completion of lymphadenectomy, the duodenum was transected craniocaudally with an endoscopic linear stapler. The hepatoduodenal mesentery was dissected approximately 4 cm along the duodenal bulb, and the anastomosis between the posterior wall of the stomach and the lesser curvature of the duodenum was created. The common entry hole was then transected using an endoscopic linear stapler, and the anastomosis was finally completed.

RESULTS

There were 36 patients with gastric cancer who underwent laparoscopic distal gastrectomy (LDG) or robotic distal gastrectomy (RDG) with B-I reconstruction using DOLFIN. There were no postoperative complications classified as C-D grade 3 or more and complications related to anastomosis, such as anastomotic leak or stenosis.

CONCLUSIONS

Our DOLFIN gastroduodenostomy can be performed safely. In addition, it results in good postoperative outcomes. A long-term comparative study is required to further evaluate the clinical usefulness of this method.

A Simple and Safe T-Shaped Esophagojejunostomy for Laparoscopic Total Gastrectomy

BACKGROUND

In laparoscopic total gastrectomy, esophago-jejunal anastomosis is still considered a complicated procedure, even though laparoscopic surgery has become widespread. Esophagojejunostomy leakage can be fatal and adversely affect postoperative cancer treatment. The leakage rate has been reported to be 2.4-5.5%, and a safer and more reliable technique needs to be established. In this multi-media article, we describe the technique of laparoscopic esophagojejunostomy using a simple and safe T-shaped esophagojejunostomy.

METHODS

We performed laparoscopic total gastrectomy with ante-colic Roux-en-Y reconstruction using a T-shaped anastomosis. First, insertion holes are made on the right side of the esophageal stump and the opposite side of the mesentery of the lift-up jejunal stump. Second, a linear stapler is inserted into each insertion hole, and a 40-45-mm V-shaped esophageal jejunal anastomosis is performed. Third, three temporary sutures are added for closing the common edge. Finally, a second stapling is used to close the entry hole and resect the esophageal stump.

RESULTS

We performed this procedure in 35 patients between May 2016 and December 2018. The median duration of surgery was 338 min (range, 248-542 min) and median bleeding was 20 mL (range, 0-240 mL). There were no esophagojejunostomy-related complications higher than Clavien-Dindo grade II. Additionally, no postoperative stenosis occurred during the follow-up period (median: 48 months, range: 4-68 months).

CONCLUSION

Considering the present results, T-shaped esophago-jejunal anastomosis is a simple and safe procedure and a promising laparoscopic total gastrectomy option.

Antemortem diagnosis of pulmonary tumor thrombotic microangiopathy associated with gastric cancer and response to immediate chemotherapy

Pulmonary tumor thrombotic microangiopathy is a rare and fatal complication of cancer that features widespread tumor cell-derived embolisms in the small arteries and arterioles of the lung and is often associated with thrombus formation. We describe the case of a 43-year-old woman who was hospitalized with cough and respiratory distress that lasted for 2 months. Computed tomography findings demonstrated multiple areas of interlobular septal thickening and ground-glass opacities in both lungs. Transthoracic echocardiography demonstrated a D-shaped left ventricle suggesting right heart overload, and pulmonary blood flow scintigraphy revealed multiple small, peripheral, and patchy areas of reduced blood flow. Upper gastrointestinal endoscopy revealed a signet-ring carcinoma. The patient was diagnosed with pulmonary tumor thrombotic microangiopathy based on her clinical presentation and treatment with tegafur, gimeracil oteracil potassium, oxaliplatin, and an anticoagulant was initiated on the 3rd day after admission. The symptoms improved rapidly after treatment initiation. The patient was discharged 28 days after initiation of chemotherapy without the need for supplemental oxygen. This case suggests that the immediate use of chemotherapy and anticoagulants for treating pulmonary tumor thrombotic microangiopathy may improve patient survival.

Self-sustaining oscillation of two axonemal microtubules based on a stochastic bonding model between microtubules and dynein

The motility of cilia and flagella plays important physiological roles, and there has been a great deal of research on the mechanisms underlying the motility of molecular motors. Although recent molecular structural analyses have revealed the components of the ciliary axoneme, the mechanisms involved in the regulation of dynein activity are still unknown, and how multiple dyneins coordinate their movements remains unclear. In particular, the mode of binding for axonemal dynein has not been elucidated. In this study, we constructed a thermodynamic stochastic model of microtubule-dynein coupling and reproduced the experiments of Aoyama and Kamiya on the minimal component of axonemal microtubule-dynein. We then identified the binding mode of axonemal dynein and clarified the relationship between dynein activity distribution and axonemal movement. Based on our numerical results, the slip-bond mechanism agrees quantitatively with the experimental results in terms of amplitude, frequency, and propagation velocity, implying that axial microtubule-dynein coupling may follow a slip-bond mechanism. Moreover, the frequency and propagation velocity decayed in proportion to the fourth power of microtubule length, and the critical load of the trigger for the oscillation agreed well with Euler's critical load.

The clinical impact of modified transpancreatic mattress sutures with polyglactin 910 woven mesh on postoperative pancreatic fistula in distal pancreatectomy

BACKGROUND

We previously reported the stump closure method for the remnant pancreas in distal pancreatectomy, in which soft coagulation and polyglycolic acid felt attached with fibrin glue were utilized. Transpancreatic mattress suture with polyglactin 910 woven mesh was recently reported as a novel stump closure technique. We developed the modified transpancreatic mattress suture with polyglactin 910 woven mesh method, which combined our polyglycolic acid felt method with the transpancreatic mattress suture with polyglactin 910 woven mesh method.

METHODS

The polyglycolic acid felt group included patients undergoing distal pancreatectomy in whom the pancreatic stump was closed with the polyglycolic acid felt method from 2017 to 2018 (n = 54); whereas the modified transpancreatic mattress suture with polyglactin 910 woven mesh group included those whose stump was closed with the modified transpancreatic mattress suture with polyglactin 910 woven mesh method from 2019 to 2020 (n = 51). Perioperative parameters, including grade B/C postoperative pancreatic fistula (clinically relevant postoperative pancreatic fistula), were assessed according to the stump closure method.

RESULTS

The incidence of clinically relevant postoperative pancreatic fistula was significantly lower in the modified transpancreatic mattress suture with polyglactin 910 woven mesh group than in the polyglycolic acid felt group (7.8% vs 22.2%, P = .036). In multivariate analysis, the use of neoadjuvant chemoradiotherapy and the transpancreatic mattress suture with polyglactin 910 woven mesh method were independent factors for preventing clinically relevant postoperative pancreatic fistula (P = .011 and 0.0038, respectively). Moreover, in the modified transpancreatic mattress suture with polyglactin 910 woven mesh group, the incidence of clinically relevant postoperative pancreatic fistula in patients with a thick pancreas (≥13 mm, 6.7%) was comparably as low as that in patients with a thin pancreas (<13 mm, 9.5%).

CONCLUSION

The modified transpancreatic mattress suture with polyglactin 910 woven mesh method is an effective stump closure technique to prevent clinically relevant postoperative pancreatic fistula after distal pancreatectomy. Our results warrant further prospective investigation to evaluate the efficacy of the modified transpancreatic mattress suture with polyglactin 910 woven mesh method compared with other standard closure methods (eg, stapler closure or hand-sewn closure).

Clinical impact of body composition on postoperative outcomes during neoadjuvant chemoradiation therapy for distal bile duct cancer

Body composition changes during neoadjuvant therapy and their clinical significance have not been clarified. The present study aimed to investigate body composition changes during neoadjuvant chemoradiation therapy (NACRT) in patients with distal bile duct cancer and the clinical impact on postoperative complications and the prognosis. A total of 16 patients with distal bile duct cancer who underwent curative resection after NACRT were retrospectively evaluated. The area of skeletal muscle, visceral fat and subcutaneous fat on computed tomography and immunological and nutritional indices were assessed before and after NACRT. All 16 patients completed NACRT followed by pancreaticoduodenectomy without mortality. There was no significant change in the skeletal muscle mass index (SMI) during NACRT. Of the 16 patients, nine (56%) were defined as sarcopenic before NACRT, and eight (50%) met the criteria for sarcopenic after NACRT. The SMI and total fat area were significantly associated with postoperative pancreatic fistula (POPF) (P=0.019 and P=0.007, respectively). The patients with sarcopenia had a shorter disease-free survival time and overall survival time in comparison to patients without sarcopenia (P=0.025 and P=0.115, respectively). In conclusion, NACRT for distal bile duct cancer did not significantly affect the body composition, or the immunological or nutritional indices. Sarcopenia after NACRT was significantly associated with early recurrence in patients with distal bile duct cancer who received NACRT.

Robotic Distal Gastrectomy Reduces Drain Amylase Values in Patients With a Small Pancreas-left Gastric Artery Angle

PURPOSE

Pancreatic fistula is a severe complication after laparoscopic distal gastrectomy (LDG). We previously evaluated the pancreas-left gastric artery angle (PLA) as a risk indicator for developing a pancreatic fistula after LDG. This study evaluated the incidence of pancreatic fistula with robotic distal gastrectomy (RDG) in comparison to LDG from the view of the PLA.

MATERIALS AND METHODS

An association between the PLA and the incidence of pancreatic fistula in 165 patients who underwent either RDG (n=45) or LDG (n=120) was investigated retrospectively.

RESULTS

RDG patients had significantly lower drain amylase values (postoperative day 2) than LDG patients. As opposed to LDG patients, drain amylase values were similar for patients with small (PLA <62 degrees) and large (PLA ≥62 degrees) PLA in RDG patients.

CONCLUSION

Robotic surgery may reduce the risk of postoperative pancreatic fistula in patients with a small PLA.

Real-world effectiveness of third- or later-line treatment in Japanese patients with HER2-positive, unresectable, recurrent or metastatic gastric cancer: a retrospective observational study

Background

Real-world evidence on the preference for and effectiveness of third- or later-line (3L +) monotherapy for HER2-positive gastric cancer is limited in Japan. This study evaluated the utility of nivolumab, irinotecan, and trifluridine/tipiracil (FTD/TPI) monotherapy as 3L + treatment in Japanese patients with HER2-positive gastric/gastroesophageal junction (G/GEJ) cancer who were previously treated with trastuzumab.

Methods

In this multicenter, retrospective, observational study (20 centers), data of eligible patients were extracted from medical records (September 22, 2017–March 31, 2020), with follow-up until June 30, 2020. Outcomes included overall survival (OS), real-world progression-free survival (rwPFS), time to treatment failure (TTF), objective response rate (ORR; complete response [CR] + partial response [PR]), and disease control rate (DCR).

Results

Of 127 enrolled patients, the overall analysis population comprised 117 patients (median [range] age, 71 [38–89] years). The most commonly prescribed 3L + monotherapy was nivolumab (n = 100), followed by irinotecan (n = 12) and FTD/TPI (n = 5). The median (95% confidence interval [CI]) OS, rwPFS, and TTF were 6.2 (4.5–8.0), 1.9 (1.5–2.3), and 1.8 (1.5–2.2) months, respectively, at median (range) 150 (25–1007) days of follow-up. The ORR (CR + PR) and DCR were 9.0% (1% + 8%) and 32.0%, respectively. Factors such as higher neutrophil–lymphocyte ratio (≥ 2.54), Glasgow prognostic score (≥ 1), Eastern Cooperative Oncology Group performance status (ECOG PS; ≥ 2), and hepatic metastasis significantly impacted OS.

Conclusions

The observed OS in this study for HER2-positive G/GEJ cancer was shorter than that reported previously, suggesting that the effectiveness of nivolumab, irinotecan, or FTD/TPI as 3L + therapy may be limited.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10147-022-02162-4.

Efficacy and safety of regorafenib in Japanese patients with advanced gastrointestinal stromal tumors

BACKGROUND

Regorafenib is an oral multi-kinase inhibitor that has been established as third-line treatment for patients after the failure of imatinib and sunitinib. However, since clinical data of regorafenib in the Japanese population are still lacking, the management of regorafenib is mainly based on the clinical experience of each oncologist. The aim of this study was to evaluate the efficacy and safety of regorafenib in a Japanese population.

METHODS

Thirty-three patients treated with regorafenib for metastatic and recurrent gastrointestinal stromal tumors were retrospectively enrolled. This study investigated the anti-tumor effect, including overall survival, progression-free survival, and safety, which was evaluated based on the incidence of adverse events.

RESULTS

The median overall survival of patients treated with regorafenib was 23.8 months and the 1-year overall survival rate was 80.0%, the median progression-free survival was 7.1 months and the 1-year progression-free survival rate was 40.2%. The responses to regorafenib were partial response in 3 cases (9.1%), stable disease in 17 (51.5%), progressive disease in 10 (30.3%), and non-evaluable in 3 (9.1%). The disease control rate was 54.0%. Treatment-related adverse events were reported in all patients, with the most common being hand-foot syndrome (72.7%), followed by liver damage (36.4%) and diarrhea (27.3%), and six patients (20.0%) were discontinued due to adverse events.

CONCLUSION

This is the first report of Japanese patients with gastrointestinal stromal tumors treated with regorafenib. Regorafenib showed efficacy and a manageable safety profile in Japanese patients with advanced gastrointestinal stromal tumors, which was comparable with previous studies.

Risk factors and long‐term postoperative outcomes in patients with postoperative dysphagia after esophagectomy for esophageal cancer

Aim

Dysphagia is one of the most common complications after esophagectomy. However, no study has investigated the long‐term postoperative outcomes in patients with postoperative dysphagia. Here, we aimed to identify risk factors for postoperative dysphagia and to investigate long‐term postoperative outcomes in such patients.

Methods

This study included 304 consecutive patients with thoracic esophageal cancer who underwent curative esophagectomy. They were diagnosed with postoperative dysphagia through a contrast videofluoroscopic swallowing study, and postoperative outcomes were compared based on swallowing function.

Results

In total, 112 patients (37%) were diagnosed with postoperative dysphagia. Older age, low BMI, and recurrent laryngeal nerve palsy were identified as independent risk factors for postoperative dysphagia. In the dysphagia group, a significantly larger number of patients developed in‐hospital pneumonia, and hospital stays were also significantly extended. After discharge, 37 (33%) patients with postoperative dysphagia developed pneumonia. Even more than 1 year after esophagectomy, a significantly larger number of patients (24 patients, 21%) with postoperative dysphagia developed pneumonia compared to those without postoperative dysphagia. Postoperative dysphagia was identified as an independent risk factor for out‐of‐hospital pneumonia. Regarding nutritional status, there was no difference in weight loss 1 year after esophagectomy, but significant weight loss was observed 2 years after esophagectomy in the dysphagia group.

Conclusion

Postoperative dysphagia was associated with both preoperative patient factors and surgical factors. Moreover, patients with postoperative dysphagia had long‐term and short‐term pneumonia risk. The personalization of long‐term follow‐up through more aggressive rehabilitation and nutritional guidance is required for patients with postoperative dysphagia.

Impact of preoperative skeletal muscle mass and physical performance on short‐term and long‐term postoperative outcomes in patients with esophageal cancer after esophagectomy

Background

Methods

Results

Conclusions