Preoperative factors associated with lateral lymph node metastasis in lower rectal cancer and the evaluation of the middle rectal artery

PURPOSE

This study aimed to identify cases in which lateral lymph node (LLN) dissection (LLND) can be excluded by clarifying preoperative factors, including an evaluation of the middle rectal artery (MRA), associated with LLN metastasis.

METHODS

Fifty-five consecutive patients who underwent preoperative positron emission tomography-computed tomography (PET/CT) and total mesorectal excision with LLND for rectal cancer were included. We retrospectively investigated the preoperative clinical factors associated with pathological LLN (pLLN) metastasis. We analyzed the regions of pLLN metastasis using MRA.

RESULTS

pLLN metastasis occurred in 13 (23.6%) patients. According to a multivariate analysis, clinical LLN (cLLN) metastasis based on short-axis size and LLN status based on PET/CT were independent preoperative factors of pLLN metastasis. The negative predictive value (NPV) was high (97.1%) in patients evaluated as negative based on PET/CT and cLLN short-axis size. MRA was detected in 24 patients (43.6%) using contrast-enhanced CT, and there was a significant relationship between pLLN metastasis and the presence of MRA. pLLN metastasis in the internal iliac region but not in the obturator region was significantly correlated with the presence of MRA.

CONCLUSION

Combined cLLN metastasis based on short-axis size and PET/CT showed a higher NPV, suggesting this to be a useful method for identifying cases in which LLND can be excluded.

Two-Team Transanal Total Mesorectal Excision and En Bloc Resection of the Lateral Pelvic Lymph Nodes, Main Iliac Vessels, and Pelvic Plexus for Locally Advanced Rectal Cancer With Lateral Lymph Node Metastasis

BACKGROUND

Here, we describe the precise surgical technique for a novel procedure involving 2-team transanal total mesorectal excision with en bloc lateral pelvic lymph node (LPLN) dissection combined with resection of the involved main internal iliac vessels and pelvic plexus.

METHODS

From September 2020 to May 2023, 4 patients underwent the procedure at our hospital.

RESULTS

The operation time and blood loss were 272 to 412 minutes and 10 to 124 mL, respectively. No patients required conversion to open surgery or exhibited Clavien-Dindo grade III or worse postoperative complications, although 2 developed grade II urinary dysfunction. All surgical margins were negative.

CONCLUSIONS

Our novel 2-team method can facilitate safe and satisfactory surgery, even for highly advanced rectal cancer. The transanal approach offers excellent visibility and operability, even during LPLN and adjacent structure dissection. Furthermore, initial dissection of the distal branches of the iliac vessels prevents excessive lymphatic tissue congestion, facilitating easier, and clearer dissection.

Efficacy of thoracic endovascular aortic repair for aorto-esophageal fistula due to esophageal cancer: a systematic review and meta-analysis

Aorto-esophageal fistula (AEF) due to esophageal cancer (EC) is a life-threatening condition characterized by sudden hemorrhage, which often causes sudden death. To evaluate the efficacy and safety of thoracic endovascular aortic repair (TEVAR) for AEF due to EC, we performed a systematic review and meta-analysis. We searched the MEDLINE (PubMed) databases, the Cochrane Library databases, Ichushi-Web (the databases of the Japan Medical Abstract Society), and CiNii (Academic information search service of the National Institute of Information from Japan) from January 2000 to November 2023 for articles about TEVAR for an emergent aortic hemorrhage (salvage TEVAR [S-TEVAR]), and the prophylactic procedure (P-TEVAR). Six studies (140 cases) were eligible for meta-analysis. The 90-day mortality of S-TEVAR and P-TEVAR was 40% (95% CI 23-60, I2 = 36%) and 8% (95% CI 3-17, I2 = 0%), respectively. Post-S-TEVAR hemorrhagic and infectious complications were 17% (95% CI 3-57, I2 = 71%) and 20% (95% CI 5-57, I2 = 66%), respectively. Post-P-TEVAR hemorrhagic and infectious complications were 2% (95% CI 0-10, I2 = 0%) and 3% (95% CI 1-12, I2 = 0%), respectively. TEVAR for AEF due to EC may be a useful therapeutic option to manage or prevent hemorrhagic oncological emergencies.

Usefulness of the preoperative inflammation-based prognostic score and the ratio of visceral fat area to psoas muscle area on predicting survival for surgically resected adenocarcinoma of the esophagogastric junction

BACKGROUND

Sarcopenic obesity is associated with gastrointestinal cancer prognosis through systemic inflammation. However, in patients with adenocarcinoma of the esophagogastric junction (AEG), the relationship between the inflammation-based prognostic score (IBPS), muscle loss, visceral fat mass, and prognosis has not been sufficiently evaluated. We investigated the prognostic value of the preoperative IBPS and the visceral fat area ratio to the psoas muscle area (V/P ratio) in patients with AEG undergoing surgery.

METHODS

We retrospectively analyzed 92 patients with AEG who underwent surgery. The prognostic value of the preoperative neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio, systemic inflammation response index, C-reactive protein-to-albumin ratio, prognostic nutritional index, modified Glasgow Prognostic Score, and V/P ratio at the third lumbar vertebra was investigated using univariate and multivariate survival analyses.

RESULTS

Multivariate analysis revealed that a high pathological stage (p = 0.0065), high PLR (p = 0.0421), and low V/P ratio (p = 0.0053) were independent prognostic factors for poor overall survival (OS). When restricted to patients with body mass index (BMI) ≥ 25 kg/m2, a high V/P ratio was a poor prognostic factor (p = 0.0463) for OS. Conversely, when restricted to patients with BMI < 25 kg/m2, a low V/P ratio was a poor prognostic factor (p = 0.0021) for OS.

CONCLUSIONS

Both PLR and V/P ratios may be useful prognostic biomarkers in surgical cases of AEG. V/P ratio and BMI may provide an accurate understanding of the muscle and fat mass's precise nature and may help predict AEG prognosis.

Squamous cell carcinoma of the anus successfully treated with multidisciplinary therapy for metachronous metastatic and local recurrences after DCF chemotherapy: a case report

BACKGROUND

Docetaxel, cisplatin, and 5-fluorouracil (DCF) chemotherapy is reportedly an effective treatment strategy for squamous cell carcinoma of the anus (SCCA). However, studies regarding its use in Japanese patients remain scarce.

CASE PRESENTATION

Here, we present the case of an 82-year-old woman with SCCA, cStage IIIB. Chemoradiotherapy was initiated after colostomy of the anorectal mass; however, para-aortic lymph node recurrence was observed 3 months after treatment completion. Five courses of DCF chemotherapy were subsequently administered, resulting in a complete response (CR). Two years and 1 month later, the aortic lymph node was enlarged again, and the patient achieved CR again after radiotherapy. Nine months later, local recurrence was detected in the anal canal, and laparoscopic perineal rectal amputation was performed. The patient remains progression-free 5 years and 10 months after the initial treatment and 1 year and 7 months after the final treatment.

CONCLUSIONS

Our findings suggest that complementary treatment after DCF chemotherapy may be efficacious in Japanese patients with SCCA and help achieve CR. Despite occasional local recurrences, this approach may help achieve long-term progression-free survival.

Impact of Perioperative Immunonutrition on Postoperative Outcomes for Patients Undergoing Head and Neck or Gastrointestinal Cancer Surgeries: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

To clarify whether perioperative immunonutrition is effective in adult patients with or without malnutrition undergoing elective surgery for head and neck (HAN) or gastrointestinal (GI) cancers.

BACKGROUND

It is important to avoid postoperative complications in patients with cancer as they can compromise clinical outcomes. There is no consensus on the efficacy of perioperative immunonutrition in patients with or without malnutrition undergoing HAN or GI cancer surgery.

MATERIALS AND METHODS

We searched MEDLINE (PubMed), MEDLINE (OVID), EMBASE, Cochrane Central Register of Controlled Trials, Web of Science Core Selection, and Emcare from 1981 to 2022 using search terms related to immunonutrition and HAN or GI cancer. We included randomized controlled trials. Intervention was defined as immunonutritional therapy including arginine, n-3 omega fatty acids, or glutamine during the perioperative period. The control was defined as standard nutritional therapy. The primary outcomes were total postoperative and infectious complications, defined as events with a Clavien-Dindo classification grade ≥ II that occurred within 30 days after surgery.

RESULTS

Of the 4825 patients from 48 included studies, 19 had upper GI cancer, 9 had lower, and 8 had mixed cancer, whereas 12 had HAN cancers. Immunonutrition reduced the total postoperative complications (relative risk ratio: 0.78; 95% CI, 0.66-0.93; certainty of evidence: high) and infectious complications (relative risk ratio: 0.71; 95% CI, 0.61-0.82; certainty of evidence: high) compared with standard nutritional therapy.

CONCLUSIONS

Nutritional intervention with perioperative immunonutrition in patients with HAN and GI cancers significantly reduced total postoperative complications and infectious complications.

Prognostic value of a modified‑immune scoring system in patients with pathological T4 colorectal cancer

Tumor-infiltrating immune cells, such as lymphocytes and macrophages, have been associated with tumor aggressiveness, prognosis and treatment response in colorectal cancer (CRC). An immune scoring system, Immunoscore (IS), based on tumor-infiltrating T cells in stage I-III CRC, was used to predict prognosis. An alternative immune scoring signature of immune activation (SIA) reflects the balance between anti- and pro-tumoral immune components. The present study aimed to evaluate the prognostic value of modified IS (mIS) and modified SIA (mSIA) in locally advanced pathological T4 (pT4) CRC, including stage IV CRC. Immunohistochemical staining for immune cell markers, such as CD3 (pan-T cell marker), CD8 (anti-tumoral cytotoxic T cell marker) and CD163 (tumor-supportive macrophage marker), in specimens from patients with radically resected pT4 CRC at stages II-IV was performed. mIS levels in the T4 CRC cohort were not associated with prognosis. However, low mSIA levels were associated with low survival. Furthermore, low mSIA was an independent predictor of recurrence in patients with radically resected pT4 CRC. In patients with CRC who did not receive postoperative adjuvant chemotherapy, low mSIA was a major poor prognostic factor; however, this was not observed in patients receiving adjuvant chemotherapy. Evaluation of the tumor-infiltrating immune cell population could serve as a valuable marker of recurrence and poor prognosis in patients with locally advanced CRC. mSIA assessment after radical CRC resection may be promising for identifying high-risk patients with pT4 CRC who require aggressive adjuvant chemotherapy.

Effectiveness of Combination Chemotherapy With Docetaxel, Nedaplatin, and 5-Fluorouracil for Advanced and Recurrent Esophageal Cancer

BACKGROUND/AIM

Chemotherapy and immunotherapy have been recently developed as potentially useful first-line treatments for unresectable, advanced, or recurrent esophageal cancer. We performed a retrospective study of the therapeutic effectiveness of triplet chemotherapy with docetaxel, nedaplatin, and 5-fluorouracil therapy for advanced, recurrent, and unresectable advanced esophageal cancer at our hospital and compared the regimen's results with those of current and possible future treatment options.

PATIENTS AND METHODS

The study cohort comprised 101 patients who received docetaxel, nedaplatin, and 5-fluorouracil for advanced or recurrent esophageal cancer at Gunma University from May 2008 to December 2017. We retrospectively evaluated the results of this combination chemotherapy and postulated future treatment strategies.

RESULTS

The overall response and disease control rates, the latter including stable disease, for docetaxel, nedaplatin, and 5-fluorouracil were 33.6% and 61.4%, respectively. The median overall survival and progression-free survival were 12.26 months and 5.1 months, respectively. In patients with recurrence, the median overall and progression-free survivals were 14.97 months (449 days) and 5.1 months (152 days), respectively. No study patients developed acute kidney injury and there were no treatment-related deaths. However, leukopenia and neutropenia were frequent hematologic toxicities.

CONCLUSION

Treatment with docetaxel, nedaplatin, and 5-fluorouracil for advanced or recurrent esophageal cancer is particularly useful for recurrent cases and has the advantage of not causing severe renal dysfunction.

Retrograde drainage for duodenal stump leakage using ileal decompression tube guided by double-balloon endoscopy: a novel case report

BACKGROUND

Duodenal stump leakage is a serious post-gastrectomy complication, and there have been no reports on endoscopic drainage.

CASE PRESENTATION

We report a case of duodenal stump leakage after laparoscopic gastrectomy with Roux-en-Y reconstruction in a 68-year-old man. First-line conservative management was ineffective. Reoperation was performed because of severe abdominal pain and increased ascites. After reoperation, duodenal stump leakage recurred with bleeding from the anterior superior pancreaticoduodenal artery. Coil embolization and pigtail catheter insertion were performed. Furthermore, we retrogradely inserted an ileal tube for tube decompression near the duodenal stump using double-balloon endoscopy for effective drainage. After tube insertion, duodenal stump leakage decreased; on the 47th primary postoperative day, the patient was discharged. The primary postoperative course was uneventful after 1 year and 9 months of follow-up.

CONCLUSIONS

This is the first successful case of duodenal stump leakage treated with retrograde decompression tube insertion near the duodenal stump using double-balloon endoscopy.

A Novel Method for Thoracoscopic Overlap Esophagogastric Reconstruction With Pleural Closure following Minimally Invasive Ivor-Lewis Esophagectomy for Esophagogastric Junction Cancer

BACKGROUND

Intrathoracic esophagogastric anastomosis following minimally invasive Ivor-Lewis esophagectomy is a technically demanding surgical technique that can result in serious intrathoracic infections when anastomotic leakage occurs. Herein, we report a novel side-overlap esophagogastric anastomosis with pleural closure for esophagogastric junction cancer.

METHODS

The 3 key points of our novel technique were the following: (1) overlap esophagogastric anastomosis and closure of the entry hole were all performed using a linear stapler; (2) the pleura was closed to separate the anastomotic site from the thoracic cavity; and (3) the mediastinal drain was inserted transhiatally from the abdominal cavity.

RESULTS

This modified anastomosis procedure was performed on 8 consecutive patients at our institution. The median overall/thoracoscopic operating time and estimated blood loss were 652.5/241.5 min and 89 mL, respectively. No mortality or serious postoperative complications occurred, and the median postoperative hospital stay was 22 days (range, 17 to 37 d).

CONCLUSION

This novel thoracoscopic overlap esophagogastric reconstruction procedure with pleural closure is safe and feasible.

The Contribution of Secondary Particles Following Carbon Ion Radiotherapy to Soft Errors in CIEDs

Introduction: While carbon ion radiotherapy is highly effective in cancer treatment, it has a high risk of causing soft error, which leads to malfunctions in cardiac implantable electrical devices (CIEDs). To predict the risk of malfunction prior to treatment, it is necessary to measure the reaction cross-sections and contributions to the soft error of secondary particles generated during treatments. Methods: A field-programmable gate array was used instead of CIEDs to measure soft errors by varying the energy spectrum of secondary particles. Results and discussion: The reaction cross-sections measured for each secondary particle were 3.0 × 10-9, 2.0 × 10-9, 1.3 × 10-8, and 1.5 × 10-8 [cm2/Mb] for thermal neutrons, intermediate-energy neutrons, high-energy neutrons above 10 MeV, and protons, respectively. The contribution of high-energy neutrons was the largest among them. Our study indicates that to reduce the risk of soft errors, secure distance and appropriate irradiation directions are necessary.

MAdCAM-1 targeting strategy can prevent colitic cancer carcinogenesis and progression via suppression of immune cell infiltration and inflammatory signals

Chronic inflammation caused by infiltrating immune cells can promote colitis-associated dysplasia/colitic cancer in ulcerative colitis (UC) by activating inflammatory cytokine signalling through the IL-6/p-STAT3 and TNFα/NF-κB pathways. Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) expressed on high endothelial venules promotes the migration of immune cells from the bloodstream to the gut via interaction with α4β7 integrin expressed on the immune cells. MAdCAM-1, has therefore drawn interest as a novel therapeutic target for treating active UC. However, the role of MAdCAM-1-positive endothelial cells in immune cell infiltration in dysplasia/colitic cancers remains unclear. We evaluated the expression of MAdCAM-1, CD31 and immune cell markers (CD8, CD68, CD163 and FOXP3) in samples surgically resected from 11 UC patients with dysplasia/colitic cancer and 17 patients with sporadic colorectal cancer (SCRC), using immunohistochemical staining. We used an azoxymethane/dextran sodium sulphate mouse model (AOM/DSS mouse) to evaluate whether dysplasia/colitic cancer could be suppressed with an anti-MAdCAM-1 blocking antibody by preventing immune cell infiltration. The number of MAdCAM-1-positive vessels and infiltrating CD8+ , CD68+ and CD163+ immune cells was significantly higher in dysplasia/colitic cancer than in normal, SCRC and UC mucosa. In AOM/DSS mice, the anti-MAdCAM-1 antibody reduced the number, mean diameter, depth of tumours, Ki67 positivity, number of CD8+ , CD68+ and CD163+ immune cells and the IL-6/p-STAT3 and TNF-α/NF-κB signalling. Our results indicate that targeting MAdCAM-1 is a promising strategy for controlling not only UC severity but also carcinogenesis and tumour progression by regulating inflammation/immune cell infiltration in patients with UC.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Experimental study on Compton camera for boron neutron capture therapy applications

Boron neutron capture therapy (BNCT) is a high-dose-intensive radiation therapy that has gained popularity due to advancements in accelerator neutron sources. To determine the dose for BNCT, it is necessary to know the difficult-to-determine boron concentration and neutron fluence. To estimate this dose, we propose a method of measuring the prompt γ-rays (PGs) from the boron neutron capture reaction (BNCR) using a Compton camera. We performed a fundamental experiment to verify basic imaging performance and the ability to discern the PGs from 511 keV annihilation γ-rays. A Si/CdTe Compton camera was used to image the BNCR and showed an energy peak of 478 keV PGs, separate from the annihilation γ-ray peak. The Compton camera could visualize the boron target with low neutron intensity and high boron concentration. This study experimentally confirms the ability of Si/CdTe Compton cameras to image BNCRs.

Erratum: Measurement of the 2νββ Decay Half-Life of ^{130}Te with CUORE [Phys. Rev. Lett. 126, 171801 (2021)]

This corrects the article DOI: 10.1103/PhysRevLett.126.171801.

Importance of Progression-free Survival in Second-line Chemotherapy in Patients With Advanced or Recurrent Gastric Cancer

BACKGROUND/AIM

Impact of second-line chemotherapy in unresectable advanced/recurrent gastric/esophagogastric junction cancer (AGC) remains unclear. This retrospective analysis aimed to identify factors affecting prognosis in chemotherapy for patients with AGC, including the importance of progression-free survival in second-line chemotherapy (PFS-2).

PATIENTS AND METHODS

Data from a total of 109 patients with AGC that received second-line treatment were analyzed with the aim of clarifying prognostic factors. Furthermore, the correlation between PFS-2 and clinical characteristics and the association between PFS-2 and inflammation-based and/or nutritional markers were investigated.

RESULTS

Multivariate analysis identified the following prognostic factors: ECOG PS ≥1, presence of peritoneal dissemination, metastasis in two or more organs, and taxane use on second-line chemotherapy. Short PFS-2 was strongly associated with prognosis in the univariate analysis [hazard ratio (HR)=3.107, 95% confidence interval (CI)=1.969-4.904, p<0.001]. The duration of PFS-2 was significantly correlated with ECOG PS (p=0.019), liver metastasis rates (p=0.035) and taxane use on second-line chemotherapy (p=0.001). In addition, weight loss rate during first-line treatment (p=0.042), white blood cell count (p=0.008), C-reactive protein (p=0.032), c-reactive protein to albumin ratio (p=0.039), prognostic index (p=0.028), and modified Glasgow prognostic score (p=0.027) were significantly associated with the duration of PFS-2.

CONCLUSION

The duration of PFS-2 significantly correlated with ECOG PS, liver metastasis, and taxane use on second-line treatment, and strongly affected OS. It was suggested that the presence of malnutrition and inflammation at the start of second-line therapy had a negative impact on PFS-2 and OS.

HLA Class I Expression Is Associated with DNA Damage and Immune Cell Infiltration into Dysplastic and Neoplastic Lesions in Ulcerative Colitis

Human leukocyte antigen class I (HLA-I) is considered a genetic pathogen for ulcerative colitis (UC). This study aimed to investigate the significance of DNA damage and HLA-I expression in infiltrating immune cells and immune checkpoint protein PD-L1 expression in dysplasia/colitic cancer (CC) and sporadic colorectal cancer (SCRC). We performed immunohistochemical staining for HLA-I, PD-L1, γH2AX (DNA damage marker), and immune cell markers such as CD8, FOXP3, CD68, and CD163 (in surgically resected specimens from 17 SCRC patients with 12 adjacent normal mucosa (NM) and 9 UC patients with 18 dysplasia/CC tumors. The ratio of membrane HLA-I-positive epithelial cells in UC and dysplasia/CC tissues was significantly higher than that in NM and SCRC. High HLA-I expression in dysplasia/CC was associated with high positivity of γH2AX and PD-L1 expression compared to SCRC. The infiltration of CD8-positive T cells and CD68-positive macrophages in HLA-I-high dysplasia/CC was significantly higher than in UC and SCRC. Dysplasia/CC specimens with DNA damage exhibited high levels of HLA-I-positive epithelial cells with high CD8- and CD68-positive immune cell infiltration compared to UC and SCRC specimens. Targeting DNA damage in UC may regulate immune cell infiltration, immune checkpoint proteins, and carcinogenesis by modulating DNA damage-induced HLA-I antigen presentation.

Surgical Techniques and Stoma-related Complications Associated With Emergency Stoma Creation

BACKGROUND/AIM

Determination of risk factors for stoma-related complications associated with emergency stoma creation may impact on reducing complications and improving the quality of life of ostomy patients; however, there are only few reports on stoma-related complications associated with emergency stoma creation. Our study aimed to identify risk factors associated with stoma-related complications after emergency surgery, and evaluate surgical techniques for good stoma creation in the emergency setting.

PATIENTS AND METHODS

A retrospective analysis of patient and surgical characteristics was performed in 104 consecutive patients who underwent ileostomy or colostomy as emergency surgery between January 2020 and December 2022 at the Gunma University Hospital.

RESULTS

Preoperative stoma site marking was performed in 70 (67.3%) patients. Colostomies and ileostomies were performed in 78 (75.0%) and 26 (25.0%) patients, respectively. The skin bridge technique was used in 13 (12.5%) patients. Stoma-related complications were diagnosed in 62 (59.6 %) patients, with peristomal skin disorders (47.1%) as the most common complication, followed by mucocutaneous separation (31.7%), and stoma retraction (19.2%). In the multivariate analysis, body mass index (BMI) [odds ratio (OR)=5.570, 95% confidence interval (CI)=1.233-25.167, p=0.026], skin bridge technique (OR=0.144, 95% CI=0.031-0.670, p=0.014), and stoma height (OR=0.134, 95% CI=0.038-0.469, p=0.002) were independent risk factors for stoma-related complications after emergency stoma creation.

CONCLUSION

In emergency stoma creation, higher BMI and lower stoma height are associated with stoma-related complications. Using the skin bridge technique could reduce the risk of stoma-related complications after emergency stoma creation.

Significance of Lipopolysaccharides in Gastric Cancer and Their Potential as a Biomarker for Nivolumab Sensitivity

Lipopolysaccharides are a type of polysaccharide mainly present in the bacterial outer membrane of Gram-negative bacteria. Recent studies have revealed that lipopolysaccharides contribute to the immune response of the host by functioning as a cancer antigen. We retrospectively recruited 198 patients with gastric cancer who underwent surgery. The presence of lipopolysaccharides was determined using immunohistochemical staining, with the intensity score indicating positivity. The relationship between lipopolysaccharides and CD8, PD-L1, TGFBI (a representative downstream gene of TGF-β signaling), wnt3a, and E-cadherin (epithelial-mesenchymal transition marker) was also investigated. Thereafter, we identified 20 patients with advanced gastric cancer receiving nivolumab and investigated the relationship between lipopolysaccharides and nivolumab sensitivity. After staining for lipopolysaccharides in the nucleus of cancer cells, 150 negative (75.8%) and 48 positive cases (24.2%) were found. The lipopolysaccharide-positive group showed increased cancer stromal TGFBI expression (p < 0.0001) and PD-L1 expression in cancer cells (p = 0.0029). Lipopolysaccharide positivity was significantly correlated with increased wnt3a signaling (p = 0.0028) and decreased E-cadherin expression (p = 0.0055); however, no significant correlation was found between lipopolysaccharide expression and overall survival rate (p = 0.71). In contrast, high TGFBI expression in the presence of LPS was associated with a worse prognosis than that in the absence of LPS (p = 0.049). Among cases receiving nivolumab, the lipopolysaccharide-negative and -positive groups had disease control rates of 66.7% and 11.8%, respectively (p = 0.088). Lipopolysaccharide positivity was associated with wnt3a, TGF-β signaling, and epithelial-mesenchymal transition and was considered to tend to promote therapeutic resistance to nivolumab.

Experimental study of intrinsic localized mode mobility in a cyclic, balanced, 1D nonlinear transmission line

Mobile intrinsic localized modes (ILMs) in balanced nonlinear capacitive-inductive cyclic transmission lines are studied by experiment, using a spatiotemporal driver under damped steady-state conditions. Without nonlinear balance, the experimentally observed resonance between the traveling ILM and normal modes of the nonlinear transmission line generates lattice drag via the production of a lattice backwave. In our experimental study of a balanced running ILM in a steady state, it is observed that the fundamental resonance can be removed over extended, well-defined driving frequency intervals and strongly suppressed over the complete ILM driving frequency range. Because both of these nonlinear capacitive and inductive elements display hysteresis our observation demonstrates that the experimental system, which is only partially self-dual, is surprisingly tolerant, regarding the precision necessary to eliminate the ILM backwave. It appears that simply balancing the cell dual nonlinearities makes the ILM envelope shape essentially the same at the two locations in the cell, so that the effective lattice discreteness seen by the ILM nearly vanishes.

Two-team Total Mesorectal Excision and Lateral Pelvic Lymph Node Dissection Using Transanal Approach for Rectal Cancer: A Retrospective Study

BACKGROUND/AIM

Lateral lymph node dissection is a locally advanced rectal cancer treatment option. Despite its complexities, such as prolonged operative time and increased blood loss, a transanal approach with an abdominal approach may help mitigate these drawbacks.

PATIENTS AND METHODS

Between July 2013 and June 2022, 40 patients underwent radical laparoscopic surgery with lateral lymph node dissection for rectal cancer. Among them, 29 and 11 patients underwent total mesorectal excision and lateral lymph node dissection without transanal approach (conventional surgery) and with transanal approach (two-team surgery), respectively. The clinical findings, surgical outcomes, pathology results, and prognoses of conventional and two-team surgeries were retrospectively compared.

RESULTS

Compared to conventional surgery, two-team surgery involves increased organ and nerve resections, shorter operation time (286 vs. 548 min, p<0.001), and less blood loss (20 vs. 158 ml, p<0.001). Although postoperative complications were similar between groups, the two-team surgery group had a shorter hospital stay (p=0.006). Pathologically, all patients who underwent two-team surgery had a distal resection margin of at least 20 mm, and no recurrence was observed. With conventional surgery, 63.6% of patients had a 10-19 mm margin, and 36.4% had a margin of ≥20 mm, except for abdominoperineal resection.

CONCLUSION

Total mesorectal excision and lateral lymph node dissection with the transanal approach as a two-team surgery are safe and feasible. Two-team surgery resulted in better outcomes than conventional surgery regarding operative time, blood loss, shorter postoperative hospital stay, and adequate distal resection margin.

Improved Algorithm for Estimation of Linear Energy Transfer in Carbon Ion Radiotherapy Plans

BACKGROUND/AIM

This study aimed to develop an improved algorithm for linear energy transfer (LET) estimation in carbon ion radiotherapy (CIRT) using relative biological effectiveness (RBE) and to establish a clinical pipeline for LET assessment.

MATERIALS AND METHODS

New approximation functions for LET versus RBE were developed for the overkill region. LET estimation performance was examined at two facilities (A and B) using archival- and Monte Carlo simulation-derived LET data, respectively, as a reference. A clinical pipeline for LET assessment was developed using Python and treatment planning systems (TPS).

RESULTS

In dataset A, LET estimation accuracy in the overkill region was improved by 80.0%. In dataset B, estimation accuracy was 2.3%±0.67% across 5 data points examined. LET distribution and LET-volume histograms were visualized for multiple CIRT plans.

CONCLUSION

The new algorithm showed a greater LET estimation performance at multiple facilities using the same TPS. A clinical pipeline for LET assessment was established.

Infiltration of Gastric Cancer Stroma by Tumor-Infiltrating Lymphocytes Correlates with Mechanistic Target of Rapamycin Signaling

INTRODUCTION

We investigated whether the infiltration of tumor-infiltrating lymphocytes (TILs) in gastric cancer (GC), as evaluated by hematoxylin and eosin (H&E) staining, could be a prognostic marker. We also explored on the relationship between TILs and mechanistic target of rapamycin (mTOR) and how it regulates immune effector responses in GC.

METHODS

A total of 183 patients with available data on TIL were included. TIL infiltration was evaluated using H&E staining. We also conducted immunohistochemistry to determine mTOR expression.

RESULTS

Positive TIL infiltration was defined as TILs ≥20%. There were 72 (39.3%) and 111 (60.7%) positive and negative cases, respectively. TILs positivity significantly correlated with both absence of lymph node metastasis (p = 0.037) and negative p-mTOR expression (p = 0.040). TIL infiltration correlated with a significantly better overall (p = 0.046) and disease-free (p = 0.020) survival.

CONCLUSION

mTOR possibly suppresses TIL infiltration in GC. H&E staining is an effective tool for evaluating the immune status of GC patients. H&E staining may be used in clinical practice to monitor treatment response in GC.

Sigmoid colon schwannoma difficult to distinguish from peritoneal dissemination 13 years after pancreatic neuroendocrine tumor surgery

BACKGROUND

Schwannoma, which clinicians sometimes struggle to diagnose, is a tumor arising from Schwann cells of peripheral nerves, often in the soft tissues and rarely in the gastrointestinal tract. Pancreatic neuroendocrine tumor (PNET) is rare among pancreatic tumors, and recurrence can occur long after resection. Here, we were presented with a case where a sigmoid colon schwannoma was difficult to distinguish from a postoperative recurrence of PNET and was diagnosed after laparoscopic resection.

CASE PRESENTATION

A 51-year-old man was diagnosed with PNET (NET G2) after a distal pancreatectomy (DP) 13 years ago. The patient underwent hepatectomy due to liver metastasis 12 years after initial radical surgery. The follow-up magnetic resonance imaging (MRI) after hepatectomy showed pelvic nodules, and laparoscopic surgery was performed for both diagnosis and treatment because peritoneal dissemination of PNET could not be ruled out. Since the tumor was in the sigmoid colon, a partial colon resection was performed. The histopathological diagnosis was a schwannoma, and the patient was discharged on the seventh postoperative day.

CONCLUSIONS

We experienced a case of sigmoid colon schwannoma that was difficult to differentiate from peritoneal dissemination of PNET and was later diagnosed after laparoscopic resection. In addition, this case involved a long-term postoperative recurrence of PNET that was amenable to radical resection, further establishing the importance of long-term imaging follow-up.

Robust Beam Selection Based on Water Equivalent Thickness Analysis in Passive Scattering Carbon-Ion Radiotherapy for Pancreatic Cancer

Carbon-ion radiotherapy (CIRT) is one of the most effective radiotherapeutic modalities. This study aimed to select robust-beam configurations (BC) by water equivalent thickness (WET) analysis in passive CIRT for pancreatic cancer. The study analyzed 110 computed tomography (CT) images and 600 dose distributions of eight patients with pancreatic cancer. The robustness in the beam range was evaluated using both planning and daily CT images, and two robust BCs for the rotating gantry and fixed port were selected. The planned, daily, and accumulated doses were calculated and compared after bone matching (BM) and tumor matching (TM). The dose-volume parameters for the target and organs at risk (OARs) were evaluated. Posterior oblique beams (120-240°) in the supine position and anteroposterior beams (0° and 180°) in the prone position were the most robust to WET changes. The mean CTV V95% reductions with TM were -3.8% and -5.2% with the BC for gantry and the BC for fixed ports, respectively. Despite ensuring robustness, the dose to the OARs increased slightly with WET-based BCs but remained below the dose constraint. The robustness of dose distribution can be improved by BCs that are robust to ΔWET. Robust BC with TM improves the accuracy of passive CIRT for pancreatic cancer.

Analysis of the relationship between LET, γH2AX foci volume and cell killing effect of carbon ions using high-resolution imaging technology

The strong cell killing effect of high linear energy transfer (LET) carbon ions is dependent on lethal DNA damage. Our recent studies suggest that induction of clusters of double-strand breaks (DSBs) in close proximity is one of the potential mechanisms. However, the relationship between LET, the degree of DSB clustering and the cell killing effect of carbon ions remains unclear. Here, we used high-resolution imaging technology to analyze the volume of γH2AX foci induced by monoenergetic carbon ions with a clinically-relevant range of LET (13-100 keV/μm). We obtained data from 3317 γH2AX foci and used a gaussian function to approximate the probability (p) that 1 Gy-carbon ions induce γH2AX foci of a given volume (vth) or greater per nucleus. Cell killing effects were assessed in clonogenic assays. The cell killing effect showed high concordance with p at vth = 0.7 μm3 across various LET values; the difference between the two was 4.7% ± 2.2%. This relationship was also true for clinical carbon ion beams harboring a mixed LET profile throughout a spread-out Bragg peak width (30-120 mm), with the difference at vth = 0.7 μm3 being 1.6% ± 1.2% when a Monte Carlo simulation-derived dose-averaged LET was used to calculate p. These data indicate that the cell killing effect of carbon ions is predictable by the ability of carbon ions to induce γH2AX foci containing clustered DSBs, which is linked to LET, providing the biological basis for LET modulation in the planning of carbon ion radiotherapy.

Primary tracheobronchial necrosis after esophagectomy: A nationwide multicenter retrospective study in Japan

Background

The clinical features of postoperative primary tracheobronchial necrosis (P‐TBN; the necrosis without anastomotic leakage or other cervical and mediastinal abscess) remains unclear. This nationwide multicenter retrospective study first investigated the clinical features of P‐TBN after esophagectomy for upper aerodigestive tract cancer with a large cohort.

Methods

As a study of the Japan Broncho‐Esophagological Society, a nationwide questionnaire survey was conducted in 67 institutions. The clinical data of 6370 patients who underwent esophagectomy for laryngeal, pharyngeal, and esophageal cancer between 2010 and 2019 were collected. Grades of P‐TBN were defined as follows: Grade 1, mucosal necrosis; Grade 2, transmural bronchial wall necrosis without fistula or perforation; Grade 3, transmural bronchial wall necrosis with fistula or perforation.

Results

P‐TBN was observed in 48 (0.75%) of 6370 patients. The incidences of P‐TBN for pharyngo‐laryngo‐cervical esophagectomy (PLCE; n = 1650), total pharyngo‐laryngo‐esophagectomy (TPLE; n = 205), and subtotal esophagectomy (SE; n = 4515) were 2.0%, 5.4%, and 0.1%, respectively. The upper mediastinal LN dissection (P = 0.016) and the higher level of the tracheal resection (P = 0.039) were significantly associated with a higher grade of necrosis in PLCE and TPLE. Overall survival rates were significantly lower in patients with Grade 2 (P = 0.009) and Grade 3 (P = 0.004) than in those with Grade 1.

Conclusion

The incidence of TBN restricted to P‐TBN was lower than previously reported. Maintaining the tracheal blood flow is essential to prevent worsening P‐TBN, especially in PLCE and TPLE. Our new P‐TBN severity grade may predict the outcome of patients with P‐TBN.

Albumin-derived Neutrophil-to-Lymphocyte Ratio Score as a Marker of Nivolumab Treatment Sensitivity in Gastric Cancer: A Multicenter Study

BACKGROUND/AIM

Establishment of powerful and easy-to-evaluate biomarkers that can predict immune checkpoint inhibitor sensitivity in patients with gastric cancer (GC) would be highly useful. The albumin-derived neutrophil-to-lymphocyte ratio (Alb-dNLR) score reportedly is an excellent measure of both immunity and nutritional status. However, the association between nivolumab treatment sensitivity and Alb-dNLR in GC has also not been adequately investigated. This multicenter retrospective study was designed to evaluate the association of Alb-dNLR with therapeutic sensitivity of nivolumab in GC patients.

PATIENTS AND METHODS

This was a retrospective multicenter study with patients from five sites. The data from 58 patients who received nivolumab for postoperative recurrent or unresectable advanced GC between October 2017 and December 2018 were analyzed. Blood tests had been performed before nivolumab administration. We analyzed the correlation between the Alb-dNLR score and clinicopathological factors, including best overall response.

RESULTS

Of the 58 patients, 21 (36.2%) comprised the disease control (DC) group and 37 (63.8%) comprised the progressive disease (PD) group. The nivolumab treatment responses were subjected to receiver operating characteristic analysis. The cutoff value was set to 2.90 g/dl for Alb and to 3.55 for dNLR. All eight patients in the high Alb-dNLR group had PD (p=0.0049). The low Alb-dNLR group had significantly better overall survival (p=0.0023) and progression-free survival rates (p<0.0001).

CONCLUSION

The Alb-dNLR score was a very simple and sensitive predictor of nivolumab therapeutic sensitivity and has very good biomarker properties.

Identification of a Functionally Efficient and Thermally Stable Outward Sodium-Pumping Rhodopsin (BeNaR) from a Thermophilic Bacterium

Rhodopsins are transmembrane proteins with retinal chromophores that are involved in photo-energy conversion and photo-signal transduction in diverse organisms. In this study, we newly identified and characterized a rhodopsin from a thermophilic bacterium, Bellilinea sp. Recombinant Escherichia coli cells expressing the rhodopsin showed light-induced alkalization of the medium only in the presence of sodium ions (Na⁺), and the alkalization signal was enhanced by addition of a protonophore, indicating an outward Na⁺ pump function across the cellular membrane. Thus, we named the protein Bellilinea Na⁺-pumping rhodopsin, BeNaR. Of note, its Na⁺-pumping activity is significantly greater than that of the known Na⁺-pumping rhodopsin, KR2. We further characterized its photochemical properties as follows: (i) Visible spectroscopy and HPLC revealed that BeNaR has an absorption maximum at 524 nm with predominantly (>96%) the all-trans retinal conformer. (ii) Time-dependent thermal denaturation experiments revealed that BeNaR showed high thermal stability. (iii) The time-resolved flash-photolysis in the nanosecond to millisecond time domains revealed the presence of four kinetically distinctive photointermediates, K, L, M and O. (iv) Mutational analysis revealed that Asp101, which acts as a counterion, and Asp230 around the retinal were essential for the Na⁺-pumping activity. From the results, we propose a model for the outward Na⁺-pumping mechanism of BeNaR. The efficient Na⁺-pumping activity of BeNaR and its high stability make it a useful model both for ion transporters and optogenetics tools.

Examining the Efficacy of Nivolumab for Gastric Cancer Focusing on Using an Inflammation-based Prognostic Score: A Multicenter Retrospective Study

BACKGROUND/AIM

To discover the positive therapeutic effects of nivolumab in patients with advanced gastric cancer (AGC), it is necessary to establish a useful biomarker to predict therapeutic efficacy. This multicenter retrospective study sought to evaluate the predictive impact of inflammation-based prognostic score (IBPS) on the therapeutic efficacy of nivolumab in patients with AGC.

PATIENTS AND METHODS

In this retrospective study, we evaluated 58 AGC patients treated with nivolumab from October 2017 to November 2018 at five institutes. Patients were categorized follows: progressive disease (PD) or disease control (DC). Blood chemistry tests were performed immediately before and after two courses of nivolumab; the correlation between best overall response and IBPS was investigated. Transition of each blood serum marker was also assessed.

RESULTS

Of 58 patients, 37 (63.8%) were in the PD group and 21 (36.2%) in the DC group. No positive correlation was noted between IBPS and therapeutic efficacy of nivolumab both immediately before and after two courses of nivolumab. However, the neutrophil-lymphocyte ratio (NLR) (p=0.045) and prognostic index (PI) (p=0.0042) before nivolumab and NLR (p=0.025), PI (p=0.0030) and Glasgow prognostic score (GPS) (p=0.043) after nivolumab were significantly correlated with treatment sensitivity. Furthermore, a decrease in PNI was an independent prognostic factor to predict nivolumab resistance on univariate analyses (p=0.0051).

CONCLUSION

Although no association between IBPS and therapeutic sensitivity was found, it is important to focus on the transition of PNI to predict therapeutic efficacy of nivolumab.

Evaluation of a therapeutic carbon beam using a G2000 glass scintillator

A G2000 glass scintillator (G2000-SC) was used to determine the carbon profile and range of a 290-MeV/n carbon beam used in heavy-ion therapy because it was sensitive enough to detect single-ion hits at hundreds of mega electron Volts. An electron-multiplying charge-coupled device camera was used to detect the ion luminescence generated during the irradiation of G2000-SC with the beam. The resulting image showed that the position of the Bragg peak can be determined. The beam passes through the 112-mm-thick water phantom and stops 5.73 ± 0.03 mm from the incident side to the G2000-SC. Additionally, the location of the Bragg peak was simulated when irradiating G2000-SC with the beam using the Monte Carlo code particle and heavy ion transport system (PHITS). Simulation results show that the incident beam stops at 5.60 mm after entering G2000-SC. The beam stop location obtained from images and the PHITS code is defined at 80% distal fall-off from the Bragg peak position. Consequently, G2000-SC provided effective profile measurements of therapeutic carbon beams.

Gangrenous ischemic colitis localized to the cecum: a case report

BACKGROUND

Ischemic colitis affects the left colon in elderly individuals and localization on the right side, especially in the cecum, is rare. We report a case of gangrenous ischemic colitis localized in the cecum of a patient undergoing hemodialysis.

CASE PRESENTATION

A 73-year-old man had been undergoing hemodialysis for chronic renal failure caused by diabetic nephropathy. He experienced frequent vomiting, diarrhea, and abdominal pain. Contrast-enhanced computed tomography revealed thickening of the cecal wall, poor enhancement, dilation of the cecum, and intrahepatic portal emphysema. No obvious abnormal findings were observed in the appendix. The patient was diagnosed with cecal necrosis and ileocecal resection was performed. Histopathological examination revealed gangrenous ischemic colitis of the cecum. He was discharged 12 days after surgery without postoperative complications.

CONCLUSION

It is important to consider the possibility of ischemic colitis of the right colon in the event of renal failure requiring dialysis, to ensure that opportunities for surgical intervention are not missed.

Selective IR super-resolution imaging of β-keratins at the bulk or interface in feather detected by using a nonlinear optical process

We developed the new IR super-resolution microscope by using a 4-wave mixing (4-wave), which is a third-order nonlinear optical process, and carried out the IR super-resolution imaging of the cross section of the rachis of an avian feather. We clearly observed strong signals in the entire region of the rachis at the amide I vibration of β-keratin in both of the XXYY and YYXX polarization combination. These results are different from images detected by using the vibrational sum-frequency generation (VSFG) method. While the VSFG imaging detects molecules only from the interface, the 4-wave method enables us to observe the signal from the bulk area. We concluded that the four repeating units of β-keratins in the bulk area which are suggested by X-ray diffraction studies are visualized in the 4-wave detected method. We also applied two IR super-resolution microscopies for the barb and discuss the site dependence of the orientation, distribution and concentration of β-keratin.

Preoperative Risk Factors and Prognostic Impact of Postoperative Complications Associated with Total Gastrectomy

INTRODUCTION

We evaluated the risk factors for patients with gastric cancer (GC) undergoing total gastrectomy (TG) that predict postoperative complications, including anastomotic leakage, postoperative pneumonia, and heart disease.

METHODS

We collected 106 patients who received TG for GC between May 2009 and May 2017 at Gunma University Graduate School of Medicine, including clinicopathologic, surgical, postoperative complication, laboratory test, and physiologic test data.

RESULTS

Of 106 patients, 92 (86.8%) had no complications, and 14 (13.2%) had complications. Univariate analyses revealed that a high American Society of Anaesthesiologists physical status (ASA-PS) and neutrophil-lymphocyte ratio (NLR) of ≥3.5 significantly correlated with postoperative complications. Multivariate analyses showed that high ASA-PS was an independent prognostic factor of postoperative complications. The cancer recurrence rate was 34.8% in the noncomplication group and 71.4% in the complication group.

CONCLUSION

Patients with postoperative complications are prone to recurrence and poor prognosis. For patients with high-risk GC with poor ASA-PS and high NLR, more thorough perioperative management is essential.

Significance of routine preoperative prone computed tomography for predicting intractable cases of inguinal hernias treated by transabdominal preperitoneal repair

Physical examination is the standard diagnostic approach for adult inguinal hernias. We aimed to evaluate the clinical utility of routine preoperative computed tomography scans in the prone position for predicting intractable cases of inguinal hernias before performing transabdominal preperitoneal repairs. We retrospectively analyzed 56 lesions in 48 patients with inguinal hernias who underwent prone computed tomography scans prior to transabdominal preperitoneal repairs. To assess the ability of prone computed tomography to enable the accurate preoperative diagnosis of inguinal hernias, we compared preoperative hernia types as classified through hernia computed tomography and intraoperative diagnosis. We also analyzed the relationship between operation time and hernia type in unilateral cases (n = 40). The overall hernia computed tomography detection and classification accuracy rates were 81.0% and 83.9%, respectively, using the Japan Hernia Society classification system (2009 version) and 84.3% and 91.2%, respectively, using the European Hernia Society classification system. There were no differences in the hernia type frequencies between the shorter (n = 20) and longer (n = 20) operation time groups. Two patients had sliding inguinal hernias with prolapsing bladders, both of which were detectable using preoperative prone computed tomography. Although transabdominal preperitoneal repairs were completed in both cases, the operation times were exceptionally long (185 and 291 minute). Preoperative prone computed tomography is useful for predicting intractable cases of inguinal hernias. Prone computed tomography can play a significant role in not only typing and differentiating hernias from other diseases, but also in helping surgeons appropriately treat unexpected intractable cases with laparoscopic surgery.

Congenital portopulmonary shunt in a cat

A 9-year-old spayed female crossbreed cat with chief complaints of anorexia and hypersalivation had high serum concentrations of ammonia and fasting and postprandial total bile acid. Therefore, she was referred to our hospital. On the first evaluation, haematology, serum chemistry, radiography and ultrasonography findings suggested that she had a congenital portosystemic shunt. CT revealed a shunt vessel from the left gastric vein to the left pulmonary vein. During median celiotomy and sternotomy, gross findings and mesenteric portography revealed abnormal vessel shunting from the left gastric vein to the left pulmonary vein. Complete ligation of the shunt vessel was achieved. She recovered without any complications. Postoperative serum chemistry revealed that ammonia and total bile acid levels decreased to within the reference intervals. This report is the first to describe the clinical features and surgical outcome of a cat with a congenital portopulmonary shunt.

Primary tracheobronchial necrosis after esophagectomy: A nationwide multicenter retrospective study in Japan

Background

The clinical features of postoperative primary tracheobronchial necrosis (P-TBN; the necrosis without anastomotic leakage or other cervical and mediastinal abscess) remains unclear. This nationwide multicenter retrospective study first investigated the clinical features of P-TBN after esophagectomy for upper aerodigestive tract cancer with a large cohort.

Methods

As a study of the Japan Broncho-Esophagological Society, a nationwide questionnaire survey was conducted in 67 institutions. The clinical data of 6370 patients who underwent esophagectomy for laryngeal, pharyngeal, and esophageal cancer between 2010 and 2019 were collected. Grades of P-TBN were defined as follows: Grade 1, mucosal necrosis; Grade 2, transmural bronchial wall necrosis without fistula or perforation; Grade 3, transmural bronchial wall necrosis with fistula or perforation.

Results

P-TBN was observed in 48 (0.75%) of 6370 patients. The incidences of P-TBN for pharyngo-laryngo-cervical esophagectomy (PLCE; n = 1650), total pharyngo-laryngo-esophagectomy (TPLE; n = 205), and subtotal esophagectomy (SE; n = 4515) were 2.0%, 5.4%, and 0.1%, respectively. The upper mediastinal LN dissection (P = 0.016) and the higher level of the tracheal resection (P = 0.039) were significantly associated with a higher grade of necrosis in PLCE and TPLE. Overall survival rates were significantly lower in patients with Grade 2 (P = 0.009) and Grade 3 (P = 0.004) than in those with Grade 1.

Conclusion

The incidence of TBN restricted to P-TBN was lower than previously reported. Maintaining the tracheal blood flow is essential to prevent worsening P-TBN, especially in PLCE and TPLE. Our new P-TBN severity grade may predict the outcome of patients with P-TBN.

Development and Applications of Compton Camera-A Review

The history of Compton cameras began with the detection of radiation sources originally for applications in astronomy. A Compton camera is a promising γ-ray detector that operates in the wide energy range of a few tens of keV to MeV. The γ-ray detection method of a Compton camera is based on Compton scattering kinematics, which is used to determine the direction and energy of the γ-rays without using a mechanical collimator. Although the Compton camera was originally designed for astrophysical applications, it was later applied in medical imaging as well. Moreover, its application in environmental radiation measurements is also under study. Although a few review papers regarding Compton cameras have been published, they either focus very specifically on the detectors used in such cameras or the particular applications of Compton cameras. Thus, the aim of this paper is to review the features and types of Compton cameras and introduce their applications, associated imaging algorithms, improvement scopes, and their future aspects.

Visualizing Bioabsorbable Spacer Effectiveness by Confirming the Distal-Tail of Carbon-Ion Beams: First-In-Human Report

In particle therapy, bioabsorbable polyglycolic acid (PGA) spacer was developed to reduce the healthy organ irradiation dose, especially in the gastrointestinal tract. The PGA spacer is safe and effective; however, there are no reports that have confirmed whether the PGA spacer which inserted in the body actually stops the carbon-ion (C-ion) beams. Here, we visualized and confirmed that the PGA spacer stops the C-ion beams in the body based on the dose distribution using auto-activation positron emission tomography (AAPET). A 59-year-old dedifferentiated retroperitoneal liposarcoma patient underwent C-ion radiotherapy (C-ion RT) on referral. A month before C-ion RT initiation, the patient underwent PGA spacer placement. Postoperatively, the patient received 4.4 Gy (RBE) per fraction of C-ion RT, followed by AAPET. AAPET revealed lower positron emitter concentrations at the distal tissue ventral to the PGA spacer than in the planning target volume. In observing the efficacy of the PGA spacer, the AAPET images and the average count per second of the positron emitter suggested that the PGA spacer stopped the C-ion beams in the body in accordance with the dose distribution. Therefore, AAPET was useful in confirming the PGA spacer's effectiveness in this study, and the PGA spacer stopped the C-ion beams.

PROX1 was associated with LGR5 and Wnt signaling and contributed to poor prognosis in gastric cancer

Introduction: We investigated prospero homeobox protein-1 (PROX1) expression in gastric cancer (GC) as a prognostic marker and its relationship with LGR5 and Wnt/β-catenin activity in GC. Methods: A total of 196 cases of patients who underwent GC surgery were retrospectively collected and reviewed. PROX1, LGR5, Wnt3a, and β-catenin expression was evaluated by using immunohistochemistry. The relationship between PROX1 expression and clinicopathological features was also evaluated. Results: The PROX1 low-expression group had 105 patients (53.6%) and the high-expression group 91 patients (46.4%). For LGR5, 76 patients (38.8%) had low expression and 120 (61.2%) high expression. The PROX1 low-expression group was significantly younger (p = 0.0095), had more intestinal type (p = 0.014), and smaller tumor size (p = 0.013). The PROX1 high-expression group significantly correlated with high LGR5 expression (p < .0001) and high Wnt3a expression (p = 0.012). There were more cases of postoperative recurrence in the PROX1 high-expression group (p = 0.013). Conclusion: Our findings show that PROX1 correlates with LGR5 and Wnt3a signaling in GC and has a poor prognosis with postoperative recurrence.

Changes in the Gustave Roussy Immune Score as a Powerful Prognostic Marker of the Therapeutic Sensitivity of Nivolumab in Advanced Gastric Cancer: A Multicenter, Retrospective Study

BACKGROUND

Identification of positive biomarkers for the effects of nivolumab on patients with advanced gastric cancer (AGC) is significant. The Gustave Roussy Immune Score (GRIm-s) is associated with therapeutic resistance of immune checkpoint inhibitors (ICIs) in other cancers. This multicenter, retrospective study was designed to analyze the association of GRIm-s with therapeutic sensitivity of nivolumab in patients with AGC.

METHODS

We reviewed 58 patients with AGC treated with nivolumab from October 2017 to November 2018 at five participating institutions. We performed blood tests before the start of nivolumab and after administration of two courses. We evaluated the correlation between the best overall response and GRIm-s. Additionally, we focused on the changes in GRIm-s before the start of nivolumab and after administration of two courses.

RESULTS

Of the 58 patients, 21 (36.2%) were classified into the disease control (DC) group and 37 (63.8%) into the progressive disease (PD) group. GRIm-s before nivolumab treatment did not correlate with the best therapeutic response (p = 0.086). However, GRIm-s after two courses of nivolumab showed that significantly more PD cases were in the high-risk group (p < 0.0001). After two courses of nivolumab, overall survival was significantly worse in the high-risk group (p < 0.0001). For progression-free survival, the high-risk group had a significantly worse prognosis both before (p = 0.04) and after two courses of nivolumab treatment (p < 0.0001).

CONCLUSIONS

GRIm-s after two courses of nivolumab and its changes compared to pretreatment values proved beneficial in predicting nivolumab sensitivity.

Patient-Derived Training Simulator for Image-Guided Adaptive Brachytherapy of Locally Advanced Cervical Cancers: Development and Initial Use

Image-guided adaptive brachytherapy (IGABT) using intracavitary and interstitial (IC/IS) techniques plays a pivotal role in definitive radiotherapy for locally advanced cervical cancers. However, the training opportunities for interstitial needle application are limited, preventing this technique from becoming widespread. This study aimed to develop a training simulator for IC/IS brachytherapy. The simulator consists of a soft silicone tumor phantom and acrylic tube mimicking the vagina; it has high visibility because of translucent materials and is compatible with computed tomography (CT) and magnetic resonance imaging (MRI). A patient harboring a typical bulky and irregular-shaped cervical tumor was selected from 495 in-house IGABT-treated candidates, and a tumor phantom (68 × 49 × 45 mm) modeled on this patient was produced from three-dimensional real-scale measurements of the MRI-based high-risk clinical target volume at first brachytherapy. In trial use by two physicians with different levels of IGABT skills, a Fletcher-Suit Asian Pacific applicator, and a Venezia applicator with interstitial needles were nicely applied to the simulator, facilitating successful creation of CT-based treatment plans consistent with clinical practice. Thus, the training simulator can be useful for the training of IC/IS brachytherapy, and warrants further research employing a greater number of phantoms and practitioners to verify its educational value.

Idiopathic pneumoperitoneum diagnosed following high-energy motor vehicular trauma:a case report

Intra-abdominal free gas is a finding of extra-intestinal gas in the abdominal cavity on radiography or CT, mainly suggesting gastrointestinal perforation and necessitating emergency surgery. Idiopathic pneumoperitoneum is diagnosed when there is no obvious gastrointestinal perforation, but there is presence of free gas in the abdominal cavity with an unidentifiable cause. Herein, we report a case of idiopathic pneumoperitoneum secondary to high-energy trauma following a car rollover accident. A 95-year-old man was transferred to our clinic after a car-to-car rollover accident. He had abrasions on his right upper arm and left abdomen that appeared to be the result of the accident;however, no other apparent traumatic injuries were noted. There was no pain in the abdomen, and peritoneal irritation symptoms were also not noted. A CT scan showed fine free air. Although idiopathic pneumoperitoneum could not be ruled out, considering the patient's background and the possibility of traumatic small bowel perforation, emergency surgery was performed. A thorough search of the abdominal cavity was performed;however, the surgery was completed without an obvious perforation site. Idiopathic pneumoperitoneum should be considered as a differential disease in cases who have free air on abdominal CT but clinically lack obvious inflammatory reaction findings. J. Med. Invest. 69 : 155-157, February, 2022.

ASO Author Reflections: Impact of the Ratio of the Visceral Fat Area (VFA) to Psoas Muscle Area (PMA) (V/P Ratio) on Survival for Patients with Surgically Resected Esophageal Cancer

PAST: The true impact of co-occurring muscle mass reduction and fat accumulation on patients with surgically resected esophageal cancer (EC) remains controversial. PRESENT: The current study defined reduction in muscle mass and excess body adiposity as the ratio of the visceral fat area (VFA) to the psoas muscle area (V/P ratio) on the same axial computed tomography slice at the third lumbar vertebra (L3). A high V/P ratio was associated with greater age (p = 0.03), higher body mass index (BMI) (p < 0.001), larger VFA (p < 0.001), and increased age-adjusted Charlson comorbidity index (ACCI) (p = 0.005). Multivariate analysis showed a high V/P ratio to be an independent prognostic factor for poor overall survival (OS) of EC patients who underwent surgery (p = 0.003). The prognostic value of the V/P ratio still was significant for EC patients with a BMI lower than 25 kg/m2. FUTURE: A high V/P ratio was an independent prognostic factor for OS of EC patients who underwent surgery, even BMI-defined non-obese EC patients. The V/P ratio as a surrogate marker of relative muscle mass reduction and fat accumulation may have prognostic value for EC patients regardless of body composition differences.

Normal Tissue Complication Probability Model for Acute Radiation Dermatitis in Patients with Head and Neck Cancer Treated with Carbon Ion Radiotherapy

PURPOSE

This study aimed to explore the prognostic factors associated with acute radiation dermatitis (ARD). A normal tissue complication probability (NTCP) model for ARD in patients with head and neck cancer (HNC) treated with carbon ion radiotherapy (CIRT) was developed.

MATERIALS AND METHODS

A total of 187 patients were included in the analysis, and the endpoint was ≥grade 2 ARD. The biological and physical dose-surface parameters associated with ARD were used in the logistic regression model. The mean areas under the receiver operating characteristic curve (AUC) in the internal cross-validation and Akaike's corrected Information Criterion (AICc) were examined for model evaluation and selection. The multivariate logistic regression NTCP models were established based on factors with weak correlation.

RESULTS

Tumour volume, planning target volume to the skin, radiation technique and all dose-surface parameters were significantly associated with ARD (P < 0.05). Models with high performance for grade 2-3 ARD were constructed. The most significant prognostic predictors were S_{40 Gy (relative biological effectiveness, RBE)} and S_{20 Gy} [absolute surface area receiving RBE-weighted dose of 40 Gy (RBE) or physical dose of 20 Gy]. The internal cross-validation-based AUCs for models with S_{40 Gy (RBE)} and S_{20 Gy} were 0.78 and 0.77, respectively. The biological and physical dose-surface parameters had similar performance at various dose levels. However, the performance of the multivariate NTCP models based on two factors was not better than that of the univariate models.

CONCLUSIONS

NTCP models for ARD may provide a basis for the development of individualised treatment strategies and reduce the incidence of severe ARD in patients with HNC receiving CIRT. Furthermore, biological and physical dose-surface parameter-based models are comparable. However, further validation with more evaluation parameters is warranted.

Impact of the Ratio of Visceral Fat Area (VFA) to Psoas Muscle Area (PMA) (V/P Ratio) on Survival for Surgically Resected Esophageal Cancer

BACKGROUND

The synergic effects of muscle mass reduction with excess body adiposity in surgically resected esophageal cancer (EC) patients remains controversial, especially in non-obese patients.

METHODS

One hundred and six patients with EC who underwent surgery between 2006 and 2014 were included in this study. Reduction in muscle mass and excess body adiposity were defined as the ratio of visceral fat area (VFA) to psoas muscle area (PMA) (V/P ratio) on the same axial computed tomography (CT) slice at the third lumbar vertebra (L3).

RESULTS

A high V/P ratio was associated with greater age (p = 0.03), higher body mass index (BMI) (p < 0.001), higher VFA (p < 0.001), and increased age-adjusted Charlson comorbidity index (ACCI) (p = 0.005). Multivariate analysis revealed a high V/P ratio to be an independent prognostic factor for poor overall survival (OS) in EC patients who underwent surgery (p = 0.003). The prognostic value of the V/P ratio was still significant in EC patients with a BMI < 25.

CONCLUSIONS

A high V/P ratio was associated with poor survival in surgically resected EC patients, even in non-obese patients. The V/P ratio as a surrogate marker of relative muscle mass reduction and fat accumulation may have prognostic value in EC patients regardless of body composition differences.