Clinical Impact of the C-reactive Protein-albumin-lymphocyte Index in Post-gastrectomy Patients With Gastric Cancer

BACKGROUND/AIM

Recently, preoperative inflammatory, immune, and nutritional statuses have attracted attention as prognostic factors in post-curative gastrectomy patients with gastric cancer (GC). The usefulness of the C-reactive protein-albumin-lymphocyte (CALLY) index as a prognostic factor in patients with various cancers, has been reported. However, reports on the clinical significance of the CALLY index in patients with GC after gastrectomy remain inadequate. In this prospective study, we focused on the preoperative CALLY index and investigated its usefulness as a prognostic factor in patients with GC.

PATIENTS AND METHODS

This study included 459 patients who underwent gastrectomy for GC between December 2013 and November 2017 at Kanagawa Cancer Center, Kanagawa, Japan. The preoperative CALLY index was calculated based on the preoperative blood test data. Patients were divided into high- and low-CALLY groups. The associations of the preoperative CALLY scores with clinicopathological factors, overall survival (OS), and recurrence-free survival (RFS) after gastrectomy for GC were evaluated.

RESULTS

The low-CALLY group was significantly older, had higher venous invasion, and a more progressive pStage than did the high-CALLY group. OS and RFS after gastrectomy in the low-CALLY group were significantly worse than those in the high-CALLY group (77.9% vs. 88.9%; p<0.001 and 73.8% vs. 87.1%; p<0.001, respectively). In the multivariate analysis, a low CALLY score was an independent prognostic factor of worse OS and RFS.

CONCLUSION

Preoperative CALLY levels may be a useful prognostic predictor in patients with GC after curative gastrectomy.

Survival Predictors Before Preoperative Adjuvant Chemotherapy in Patients With Locally Advanced Esophageal Squamous Cell Carcinoma

BACKGROUND/AIM

Radical resection after preoperative adjuvant chemotherapy (NAC) is a standard treatment for patients with locally advanced esophageal squamous cell carcinoma (LAESCC), but its outcome remains unsatisfactory. In order to develop a personalized treatment program for LAES, we herein compared the survival prediction utility of five pre-NAC nutritional, inflammatory, and immune indexes in patients with LAESCC.

PATIENTS AND METHODS

We evaluated the survival of 203 patients with LAESCC who underwent radical resection after NAC from January 2011 to September 2019 for the following representative pre-NAC nutritional, inflammatory, and immune indices: modified Glasgow Prognostic Score, Prognostic Nutritional Index, C-reactive protein/albumin ratio, serum neutrophil/lymphocyte ratio, and Geriatric Nutrition Risk Index (GNRI) were evaluated for their impact on survival.

RESULTS

Of the five indices, GNRI was the best predictor of survival as determined by the area under the curve (p<0.05). When patients were divided into three groups according to the nutritional risk assessment of Bouillanne et al. using the pre-NAC GNRI, the 5-year overall survival (OS) and recurrence-free survival (RFS) were significantly stratified (p<0.001). On multivariate analysis, the GNRI independently identified a poor OS group [group 1: hazard ratio (HR)=2.598, p=0.002; group 2: HR=6.257, p<0.001] and a high recurrence risk group (group 1: HR=1.967, p=0.016; group 2: HR=4.467, p<0.001).

CONCLUSION

In patients with LAESCC, GNRI may be the most accurate, reliable, and useful prognostic factor among the five major systemic inflammatory and nutritional indices.

Comparison of Dietary Intake After Gastric Cancer Gastrectomy Between Patients With and Without Postoperative Surgical Complications

BACKGROUND/AIM

This study aimed to compare dietary intake (DI) after gastrectomy for gastric cancer between patients with (C group) and without (NC group) postoperative surgical complications.

PATIENTS AND METHODS

This prospective observational study enrolled patients who underwent gastrectomy for gastric cancer. DI was assessed using a food frequency questionnaire with 82 food items (FFQW82) during nutritional counseling before surgery and at one and three months after surgery.

RESULTS

A total of 225 patients participated in this study. Of the 225 patients, 193 had no postoperative complications, and 32 had postoperative complications (Clavien-Dindo grade ≥2). The median DI at 1 month postoperatively was 1508 kcal/day in the NC group and 1,470.5 kcal/day in the C group (p=0.175). The median DI at 3 months postoperatively was 1,623 kcal/day in the NC group and 1575 kcal/day in the C group (p=0.473). There was a significant difference between the NC and C groups in the rate of decrease in DI at one month (median: -8.44% vs. -15.37%, p=0.032) and at three months postoperatively (median: -3.58% vs. -6.12%, p=0.038).

CONCLUSION

There was a statistically significant difference in the rate of decrease in DI after gastrectomy between the C and NC groups at 1 and 3 months postoperatively. Our results suggest that patients with postoperative surgical complications require additional nutritional treatment for decreased DI.

Clinical Significance of Tryptophanyl-tRNA Synthetase 1 Gene Expression in Patients With Locally Advanced Gastric Cancer

BACKGROUND/AIM

The tryptophanyl-tRNA synthetase 1 gene (WARS1), encodes a tryptophan-tRNA synthetase involved in the amino acidification of tryptophan-tRNA and has been reported to be involved in cancer cell growth, metastasis promotion, and drug resistance in a variety of cancers. This study investigated the clinical significance of WARS1 expression as a biomarker in gastric cancer tissues obtained from patients with locally advanced gastric cancer (GC) who underwent radical resection.

PATIENTS AND METHODS

WARS1 expression in GC tissues and adjacent normal gastric mucosa of 253 patients with pStage II/III GC who underwent curative resection was determined using quantitative polymerase chain reaction (PCR). Association of WARS1 expression levels, categorized into high and low expression based on the median expression levels, with clinicopathological factors and overall survival (OS) of these patients was assessed.

RESULTS

The low-WARS1 expression group had significantly higher serosal invasion, lymph node metastasis, lymphatic invasion, venous invasion, and pathological stage than did the high-WARS1 expression group. OS was significantly worse in the low- than in the high-WARS1 expression group (5-year survival 52.2% vs. 75.9%; p=0.0001). Furthermore, in multivariate analysis, low WARS1 expression was an independent predictor for poor OS (hazard ratio=2.101; 95% confidence interval=1.328-3.322; p=0.002).

CONCLUSION

In patients with locally advanced GC, after curative resection, WARS1 expression in GC tissue may be a useful prognostic marker.

Dietary Intake After Surgery in Patients With Gastric Cancer Who Underwent Laparoscopic-assisted Versus Those Who Underwent Conventional Gastrectomy

BACKGROUND/AIM

Dietary intake (DI) loss after gastrectomy is a serious problem for patients with gastric cancer. This study compared the dietary intake after surgery in patients with early gastric cancer who received laparoscopic distal gastrectomy (LDG) versus those who underwent conventional open distal gastrectomy (ODG).

PATIENTS AND METHODS

This was a prospective, observational study enrolling patients who underwent gastrectomy for gastric cancer. Dietary intake was assessed using the food frequency questionnaire with eighty-two food items (FFQW82) at nutritional counseling before surgery and one and three months after surgery.

RESULTS

A total of 118 patients were included. Among them, 69 (58.5%) were male, and 49 (41.5%) were female. Seventy-five (63.6%) received LDG, and 43 (36.4%) received ODG. At 1 month postoperatively, the median DI in the LDG group was 1,540 (1,014-2,195) kcal/day, whereas that in the ODG group was 1547 (986-2,143) kcal/day (p=0.891). At 3 months postoperatively, the median DI in the LDG group was 1,624 (1,050-2,443) kcal/day, and that in the ODG group was 1,652 (917-2,144) kcal/day (p=0.749). There was no significant difference in the DI loss rate at 1 month (median: -8.2% vs. -9.3%, p=0.398) and 3 months (median: -3.2% vs. -3.7%, p=0.635) between the LDG and ODG groups.

CONCLUSION

Minimally invasive laparoscopic surgery may not prevent postoperative DI loss after distal gastrectomy. Therefore, methods other than laparoscopic surgery are needed to prevent post-gastrectomy DI loss.

Clinical Significance of Prealbumin Level Measurement Before Neoadjuvant Chemotherapy in Elderly Patients With Locally Advanced Esophageal Cancer

BACKGROUND/AIM

Radical esophagectomy after preoperative neoadjuvant chemotherapy (NAC) is the standard treatment for locally advanced esophageal squamous cell carcinoma (ESCC). However, careful treatment selection is required when considering organ function in elderly patients. Prealbumin, a rapid turnover protein, is a short-term dynamic nutritional index, and its relationship with long-term postoperative survival in various cancers has been previously reported. However, the association between serum prealbumin level before NAC and survival in elderly patients remains unclear. This study investigated the clinical significance of prealbumin level measurement before NAC in elderly patients with locally advanced ESCC who underwent surgery after NAC.

PATIENTS AND METHODS

Eighty patients aged ≥65 years diagnosed with cStage II/III ESCC and undergoing radical esophagectomy after cisplatin and 5-fluorouracil therapy as NAC, were included. The cutoff value of the serum prealbumin level before NAC was set at 18.2 mg/dl using receiver operating characteristic curve analysis, and postoperative complications, recurrence, and overall survival were compared between the low and high prealbumin groups.

RESULTS

There were no differences in patient background, clinicopathological characteristics, postoperative complications, or recurrence-free survival between the two groups. Overall survival (OS) was significantly worse in the low prealbumin group than in the high prealbumin group (5-year survival, 33.3% vs. 67.0%; p=0.0341). Furthermore, on univariate and multivariate analysis, low prealbumin level was an independent poor OS factor (p=0.036).

CONCLUSION

In elderly patients with locally advanced ESCC, serum prealbumin level before NAC may be a useful prognostic factor and may be important in selecting a treatment strategy that considers individual organ function.

Clinical Significance of Pregnancy Zone Protein Expression in Patients With Locally Advanced Gastric Cancer After Curative Resection

BACKGROUND/AIM

Pregnancy zone protein (PZP), encoded by PZP, belongs to the α-2-macroglobulin superfamily, and plays an important role in inflammatory responses and immune cell activation in cancer. However, the relationship between gastric cancer (GC) and PZP is poorly studied. This study investigated the clinical significance of PZP expression in GC tissues of patients with locally advanced GC after curative resection.

PATIENTS AND METHODS

Using quantitative polymerase chain reaction, we measured PZP expression in GC tissues and adjacent normal gastric mucosa of 253 patients with pStage II/III GC who underwent curative resection. We compared the expression levels of PZP in GC tissues and adjacent normal gastric mucosa and examined the relationship of PZP expression in GC tissues with clinicopathological factors and overall survival (OS).

RESULTS

PZP expression was significantly associated with histology, venous invasion, and pathological stage. The high PZP expression group had significantly worse OS than did the low expression group (5-year survival 48.6% vs. 68.5%, p=0.0003). Furthermore, in multivariate analysis, high PZP expression was an independent factor for poor OS (hazard ratio=1.984, 95% confidence interval=1.307-3.012, p=0.0013).

CONCLUSION

In post-curative resection patients with locally advanced GC, PZP expression in GC tissue may be a useful prognostic marker.

Significance of Preoperative Modified Nutritional Risk Index in Patients With Gastric Cancer After Curative Resection

BACKGROUND/AIM

A new modified nutritional risk index (mNRI), calculated using serum albumin (g/l)+body mass index (BMI) [weight (kg_/height2 (m2)], is a good predictor of postoperative complications and cancer survival. However, no study has used this index in patients with gastric cancer (GC). Therefore, we aimed to investigate the clinical significance of the preoperative mNRI values in patients with GC who underwent curative resection.

PATIENTS AND METHODS

We examined 449 patients who underwent curative resection for GC at Kanagawa Cancer Center between 2013 and 2017. The mNRI cutoff value obtained using a receiver operating characteristic analysis was 23.31. Patients were divided into high and low mNRI groups according to the cutoff value, and the clinicopathological characteristics and outcomes were compared between the two groups.

RESULTS

In terms of clinicopathological characteristics, the high mNRI group had a higher proportion of men, higher BMI, and a higher proportion of patients with American Society of Anesthesiologists physical status class 2/3 compared with the low mNRI group; the low mNRI group had significantly worse 5-year recurrence-free survival (RFS) and overall survival (OS) than the high mNRI group (OS, p=0.005) (OS, p=0.006; RFS, p=0.018) did. In the multivariate analysis, a low mNRI was an independent predictor of OS (p=0.006) and RFS (p=0.013).

CONCLUSION

Preoperative mNRI may be a useful recurrence and prognostic biomarker in patients with GC who have undergone curative resection.

Asialoglycoprotein Receptor 2 Expression in Patients With Locally Advanced Gastric Cancer After Curative Resection

BACKGROUND/AIM

The asialoglycoprotein receptor 2 gene (ASGR2) encodes a subunit of the asialoglycoprotein receptor, a transmembrane protein, which has recently been reported to be involved in gastric cancer (GC) progression. This study aimed to investigate the clinical significance of ASGR2 expression in GC tissues of patients with locally advanced gastric cancer (LAGC) after curative resection.

PATIENTS AND METHODS

ASGR2 expression was measured in GC tissues and adjacent normal gastric mucosa in 253 patients with pStage II/III GC who underwent curative resection, by using quantitative polymerase chain reaction. We compared the expression levels in GC tissues and adjacent normal stomach mucosa, and evaluated the relationship of its expression in GC tissues with clinicopathological factors and overall survival (OS).

RESULTS

ASGR2 expression was significantly associated with lymph node metastasis and venous invasion. The high ASGR2-expression group demonstrated significantly lower survival than the low expression group (5-year survival 55.5% vs. 72.6%; p=0.009). Furthermore, in multivariate analysis, high ASGR2 expression was an independent factor for poor OS (hazard ratio=2.030; 95% confidence interval=1.318-3.127; p=0.001).

CONCLUSION

ASGR2 expression in GC tissues may be a useful prognostic marker in patients with LAGC after curative resection.

Clinical Significance of Chitinase-3-like Protein 1 Gene Expression in Patients With Locally Advanced Gastric Cancer

BACKGROUND/AIM

Chitinase-3-like protein 1 (CHI3L1), encoded by CHI3L1, is thought to be involved in growth, invasion, migration, and resistance to chemotherapy in cancer. This study aimed to investigate the clinical significance of CHI3L1 expression as a biomarker in gastric cancer (GC) tissues of patients with locally advanced GC after curative resection.

PATIENTS AND METHODS

Quantitative polymerase chain reaction (PCR) was used to determined CHI3L1 expression in GC tissues and adjacent normal gastric mucosa of 253 patients with pStage II/III GC who underwent curative resection. We compared the expression levels in GC tissues and adjacent normal gastric mucosa, and examined the relationship between expression in GC tissues and clinicopathological factors and overall survival (OS) in these patients.

RESULTS

CHI3L1 expression was significantly associated with lymph-node metastasis and venous invasion. OS rate was significantly lower in the high- than in the low-CHI3L1 expression group (5-year survival 55.5% vs. 72.6%; p=0.009). Furthermore, in multivariate analysis, high CHI3L1 gene expression was an independent factor for poor OS (hazard ratio=2.030; 95% confidence interval=1.318-3.127; p=0.001).

CONCLUSION

In patients with locally advanced GC after curative resection, expression of the CHI3L1 in GC tissue may be a useful prognostic marker.

Intraoperative Blood Loss Impacts Recurrence and Survival in Patients With Locally Advanced Esophageal Cancer

BACKGROUND/AIM

Intraoperative blood loss (IBL) has been reported to decrease survival after surgical resection of some malignancies; however, there are few reports on the effects of IBL on recurrence and survival in locally advanced esophageal cancer. Therefore, we investigated the relationship between IBL and postoperative recurrence and overall survival in patients who underwent surgery for esophageal cancer.

PATIENTS AND METHODS

One hundred and ninety-eight patients with locally advanced esophageal cancer who underwent preoperative adjuvant chemotherapy and curative resection as standard treatment were included in this study. Based on a defined cut-off value for IBL, 27 and 171 patients were classified into the high and low IBL groups, respectively. The relationship between each group and clinicopathological factors, postoperative recurrence, and overall survival were investigated.

RESULTS

In terms of the relationship between IBL and clinicopathological factors, the high IBL group had significantly more patients with pathological T4, longer operative time, and higher incidence of postoperative complications than the low IBL group. Both recurrence-free and overall survival were significantly worse in the high IBL group than in the low IBL group. Furthermore, multivariate analysis identified high IBL as an independent factor for predicting poor reference free survival and overall survival.

CONCLUSION

Heavy IBL in patients with locally advanced esophageal cancer may be a useful predictor of postoperative recurrence and overall survival.

Evaluation of Irinotecan and Trifluridine/Tipiracil as Fourth-line Treatments After Third-line Nivolumab for Advanced Gastric Cancer

BACKGROUND/AIM

Irinotecan and trifluridine/tipiracil (FTD/TPI) are fourth-line treatment options after third-line nivolumab for advanced gastric cancer (AGC). However, the efficacy and safety of irinotecan and FTD/TPI in the fourth-line setting after third-line nivolumab remains unclear. This study aimed to evaluate the efficacy and safety of irinotecan and FTD/TPI in the fourth-line setting after third-line nivolumab.

PATIENTS AND METHODS

We identified 137 AGC patients treated with nivolumab as third-line treatment in our institute between October 2017 and July 2021. Of these, we recruited 19 AGC patients who initiated irinotecan and 23 AGC patients who initiated FTD/TPI in the fourth-line setting until September 2021.

RESULTS

The median overall survival was 5.83 months for irinotecan and 6.31 months for FTD/TPI. Median time-to-treatment failure was 2.07 months for irinotecan and 1.64 months for FTD/TPI. While the frequency of all-grade diarrhea was higher in irinotecan (36% vs. 17%), grade ≥3 neutropenia tended to be higher in FTD/TPI (21% vs. 35%).

CONCLUSION

Irinotecan and FTD/TPI may be clinically useful as fourth-line treatments after nivolumab.

Clinical Effect of the C-Reactive Protein to Serum Albumin Ratio in Patients with Metastatic Gastric or Gastroesophageal Junction Cancer Treated with Trifluridine/Tipiracil

Trifluridine/tipiracil (FTD/TPI) is an oral anticancer agent used as a third- or later-line treatment for patients with metastatic gastric cancer/gastroesophageal junction cancer (mGC/GEJC). The C-reactive protein-to-serum albumin ratio (CAR) is an inflammation-based prognostic marker in gastric cancer. This retrospective study evaluated CAR's clinical significance as a prognostic factor in 64 patients with mGC/GEJC administered FTD/TPI as a third- or later-line therapy. Patients were categorized into high- and low-CAR groups based on pre-treatment blood data. This study evaluated associations between CAR and overall survival (OS), progression-free survival (PFS), clinicopathological features, treatment efficacy, and adverse events. The high-CAR group had significantly worse Eastern Cooperative Oncology Group performance status, a higher prevalence of patients administered with a single course of FTD/TPI, and a higher rate of patients not administered chemotherapy after FTD/TPI therapy than the low-CAR group. Median OS and PFS were significantly poorer in the high-CAR group than in the low-CAR group (113 vs. 399 days; p < 0.001 and 39 vs. 112 days; p < 0.001, respectively). In multivariate analysis, high CAR was an independent prognostic factor for OS and PFS. The overall response rate was not significantly different between the high- and low-CAR groups. Regarding adverse events, the high-CAR group had a significantly lower incidence of neutropenia and a higher incidence of fatigue than the low-CAR group. Therefore, CAR may be a potentially useful prognostic factor for patients with mGC/GEJC treated with FTD/TPI as third- or later-line chemotherapy.

Non-curative resection for surgical T4b esophageal cancer: esophagectomy or non-esophagectomy?

BACKGROUND

Recently, with the development of multidisciplinary treatment, the treatment outcomes of esophageal cancer (EC) have improved. However, despite advances in diagnostic imaging modalities, preoperative diagnosis of T4 EC is still difficult, and the prognosis of T4 EC remains very poor. In addition, the prognosis of surgical T4b EC (sT4b EC) after surgery remains unclear. In this study, we retrospectively reviewed sT4b EC.

METHODS

We evaluated the clinical course of sT4b EC and compared palliative esophagectomy with R2 resection (PE group) with other procedures without esophagectomy (NE group) (e.g., only esophagostomy) for sT4b EC.

RESULTS

Forty-seven patients with thoracic EC underwent R2 resection at our institution between January 2009 and December 2020. Thirty-four patients were in the PE group, and 13 patients were in the NE group. The 2-year overall survival rate was 0% in the PE group and 20.2% in the NE group (p = 0.882). There was one case of long-term survival in the NE group that underwent surgery followed by definitive chemoradiation. Postoperative complications (Clavien-Dindo grade ≥ 3) were observed in 25 patients (73.5%) in the PE group and in three patients (23.1%) in the NE group (p = 0.031). The median time to the initiation of postoperative treatment was 68.1 days in the PE group and 18.6 days in the NE group (p = 0191).

CONCLUSIONS

If EC is diagnosed as sT4b, palliative esophagectomy should be avoided because of the high complication rate and the lack of long-term survival.

Significance of lymphovascular invasion in esophageal squamous cell carcinoma undergoing neoadjuvant chemotherapy followed by esophagectomy

BACKGROUND

Lymphovascular invasion (LVI) was previously reported to be an independent factor associated with survival in locally advanced esophageal squamous cell carcinoma (LAESCC) patients receiving neoadjuvant chemotherapy (NAC); however, the detailed clinicopathological significance of LVI remains unclear. This study evaluated the prognostic impact of LVI in patients with LAESCC after NAC with cisplatin and 5-fluorouracil (CF) or docetaxel, cisplatin and 5-fluorouracil (DCF) followed by surgery and in LAESCC patients with recurrence after NAC and surgery.

METHODS

438 patients with thoracic LAESCC who had undergone NAC followed by an esophagectomy with three-field lymphadenectomy were assessed using a propensity score matched analysis, and their long-term outcomes were retrospectively reviewed.

RESULTS

In matched cohort, a multivariate analysis of relapse-free survival (RFS) in the NAC-CF group suggested that ypN (≥ 1, HR = 3.715, p = 0.004) and LVI (positive, HR = 3.366, p = 0.012) were independent factors associated with RFS; in the NAC-DCF group, ypN (≥ 1, HR = 4.829, p < 0.001) was the only independent factor associated with RFS. Comparisons of overall survival (OS) between the ypN + /LVI + group and other groups among patients with recurrence in each NAC regimen showed significant differences in both of NAC groups (p < 0.001, respectively). The ypN + /LVI + group had a significantly poor OS in both an oligometastatic recurrence (OMR) group (p < 0.001) and a non-OMR group (p < 0.001).

CONCLUSIONS

The present study suggested that the independent factor associated with prognosis of patients with LAESCC after NAC and surgery may differ according to the NAC regimen, and the presence of both ypN and LVI was a prognostic factor for patients with recurrence, including those with OMR. These results might be helpful when deciding on an additional treatment strategy for LAESCC patients.

Clinical Significance of Neutrophil-to-Lymphocyte Ratio/Serum Albumin Ratio in Patients With Metastatic Gastric or Gastroesophageal Junction Cancer Administered Trifluridine/Tipiracil

BACKGROUND/AIM

Trifluridine/tipiracil (FTD/TPI) is an anticancer-agent that is administered as third-line or later chemotherapy for metastatic gastric/gastroesophageal junction cancer (mGC/GEJC). Although inflammatory and nutritional statuses have attracted attention as prognostic factors for patients with mGC/GEJC in this therapy, their usefulness has not been fully clarified. Thus, this study investigated the clinical significance of prognostic nutritional index (PNI), neutrophil/lymphocyte ratio (NLR), and NLR/serum albumin (Alb) ratio in patients administered FTD/TPI.

PATIENTS AND METHODS

This retrospective study included 64 patients who underwent FTD/TPI treatment for mGC/GEJC at Kanagawa Cancer Center, Kanagawa, Japan, between October 2019 and June 2022. Patients were divided into high and low PNI, NLR, and NLR/Alb groups according to their pretreatment blood data. This study evaluated the associations between the inflammatory and nutritional indexes and survivals.

RESULTS

Overall survival (OS) and progression-free survival (PFS) of patients with low PNI were significantly poorer than those with high PNI. However, low PNI was not an independent prognostic factor for OS and PFS. There was no significant association between NLR and OS or PFS. In contrast, the OS of patients with high NLR/Alb was significantly poorer than those with high PNI and low NLR/Alb. Furthermore, multivariate analysis showed that high NLR/Alb was an independent prognostic factor for OS.

CONCLUSION

The NLR/Alb may be a useful prognostic factor in patients with mGC/GEJC being administered FTD/TPI as third-line or later chemotherapy.

Surveillance Strategy after Curative Resection for Oesophageal Squamous Cell Cancer Using the Hazard Function

Background

The optimal surveillance period and frequency after curative resection for oesophageal squamous cell carcinoma (OSCC) remain unclear, and current guidelines are mainly based on traditional Kaplan–Meier analyses of cumulative incidence rather than risk analysis. The aim of this study was to determine a suitable follow-up surveillance program following oesophagectomy for OSCC using the hazard function.

Methods

A total of 1187 patients who underwent curative resection for OSCC between 2000 and 2014 were retrospectively analyzed. The changes in the estimated hazard rates (HRs) of recurrence over time were analyzed according to tumour-node-metastasis stage.

Results

Four hundred seventy-eight (40.2%) patients experienced recurrence during the follow-up period (median, 116.5 months). The risk of recurrence peaked at 9.2 months after treatment (HR = 0.0219) and then decreased to half the peak value at 24 months post-surgery. The HRs for Stage I and II patients were low (< 0.007) post-treatment. The HR for Stage III patients peaked at 9.9 months (HR = 0.031) and the hazard curve declined to a plateau at 30 months. Furthermore, the HR peaked at 10.8 months (HR = 0.052) in Stage IV patients and then gradually declined from 50 months.

Conclusions

According to tumour-node-metastasis stage, changes in the HRs of postoperative recurrence in OSCC varied significantly. Intensive surveillance should be undertaken for 3 years in Stage III patients and for 4 years in Stage IV patients, followed by annual screening. For Stage I OSCC patients, a reduction in the surveillance intensity could be taken into consideration.

Clinicopathological Features of Early-Stage Esophageal Carcinosarcoma

Esophageal carcinosarcoma (EC) is a rare malignant tumor, accounting for 0.5–2.8% of esophageal cancers. Most are advanced cancers that are detected as polypoid lesions and are treated with multidisciplinary therapy with a focus on surgery. However, endoscopic findings, pathological findings, and long-term outcomes of early-stage EC are often unclear because there are very few reported cases. This paper reports three cases of EC confined to the mucosal layer. The macroscopic type of all tumors was polypoid lesion with a slightly depressed lesion. All cases were clinically diagnosed as invasive cancer before treatment. Pathological diagnosis of tumor depth showed that one case had invaded the lamina propria mucosae, and two cases had invaded the muscularis mucosae (MM). One case of diagnosed MM had lymphoid invasion and lymph node metastasis to the upper mediastinum. After 1 year, although adjuvant treatment had been administered, there was lymph node recurrence in the left upper clavicle, and thus chemoradiation therapy was performed. Two other cases survived without recurrence. Early-stage EC is characterized by polypoid lesions with a slightly depressed lesion, and it is challenging to predict the histology on biopsy. Furthermore, it is difficult to determine the depth of invasion in the MM and submucosal layer in squamous cell carcinoma by endoscopy alone, and hence depth diagnosis by multiple modalities should be considered.

Predictive Ability of the Five-time Chair Stand Test for Postoperative Pneumonia after Minimally Invasive Esophagectomy for Esophageal Cancer

BACKGROUND

The revised sarcopenia guidelines proposed handgrip strength (HGS) and five-time chair stand test (5-CST) as the primary parameters of muscle function. HGS and 5-CST are associated with pulmonary function among community-dwelling people, although few reports have described an association between these parameters and surgical outcomes in carcinomas. We examined the predictive ability of 5-CST for postoperative pneumonia after minimally invasive esophagectomy (MIE) compared with that of HGS.

METHODS

This retrospective, single-center, observational study evaluated 222 male patients who underwent MIE for esophageal cancer between February 2018 and October 2020. Sarcopenia parameters included 5-CST, HGS, and skeletal muscle index. Postoperative pneumonia predictors were determined by using multivariate logistic regression analysis. We assessed the net reclassification improvement (NRI) and integrated discrimination improvement (IDI) to analyze the predictive ability of 5-CST and HGS.

RESULTS

MIE was performed for squamous cell carcinoma (n = 179), adenocarcinoma (n = 38), and other cancers (n = 5). Forty-nine (22.1%) patients developed postoperative pneumonia. Multivariate logistic regression showed that age (odds ratio [OR] 1.05; 95% confidence interval [CI] 1.01-1.10; p = 0.027), 5-CST (OR, 1.19; 95% CI 1.00-1.40; p = 0.046), and recurrent laryngeal nerve palsy (RLNP) (OR, 3.37; 95% CI 1.60-7.10; p = 0.001) significantly predicted postoperative pneumonia. Category-free NRI and IDI showed that adding 5-CST in the prediction model with age and RLNP resulted in significantly greater reclassification and discrimination abilities than did HGS.

CONCLUSIONS

The 5-CST significantly predicted postoperative pneumonia after MIE. NRI and IDI analyses suggested that 5-CST had significantly better predictive ability for postoperative pneumonia than did HGS.

Salvage minimally invasive esophagectomy after definitive chemoradiotherapy for esophageal cancer can improve postoperative complications compared with salvage open esophagectomy

BACKGROUND

Although the advantage of minimally invasive esophagectomy (MIE) over open esophagectomy (OE) in planned esophagectomy is being established, the utility of salvage MIE (S-MIE) remains unclear. We aimed to investigate the feasibility and advantage of S-MIE compared with salvage OE (S-OE).

METHODS

We retrospectively assessed 82 patients who underwent salvage esophagectomy after definitive chemoradiotherapy for thoracic esophageal cancer between January 2007 and April 2020. Perioperative factors and postoperative complications were compared between the S-OE group (n = 62) and the S-MIE group (n = 20). Logistic regression analysis was performed to analyze the factors associated with postoperative complications.

RESULTS

Regarding the patients' preoperative characteristics, the S-OE group had a significant number of grade ≥ cT3 patients vs the S-MIE group (69% vs 35%, respectively; p = 0.006), whereas ycT rates were comparable. Compared with S-OE, S-MIE had comparable operative time, number of harvested thoracic lymph nodes, and R0 resection, but significantly less estimated blood loss (150 ml and 395 ml, respectively; p = 0.003). Regarding postoperative complications, total complications (79% vs 50%; p = 0.01) and pneumonia (48.3% vs 20%; p = 0.02) rates were significantly lower with S-OE vs S-MIE, respectively. On multivariate analysis, S-MIE was an independent factor associated with postoperative pneumonia (odds ratio: 0.29, 95% confidence interval: 0.06-0.99; p = 0.04) and total complications (odds ratio: 0.26, 95% confidence interval: 0.07-0.86; p = 0.02).

CONCLUSION

S-MIE was feasible for salvage esophagectomy, with favorable short-term outcomes vs S-OE regarding postoperative pneumonia and total complications.

Feasibility of conversion thoracoscopic esophagectomy after induction therapy for locally advanced unresectable esophageal squamous cell carcinoma

BACKGROUND

Recently, patients with cT4b esophageal cancer often require conversion surgery following induction therapy, for which the standard procedure is open esophagectomy. However, thoracoscopic esophagectomy, including thoracoscopic esophagectomy in the prone position, is increasingly used. We compared short-term outcomes of thoracoscopic esophagectomy and open esophagectomy in this setting.

METHODS

We retrospectively analyzed 14 patients who underwent thoracoscopic esophagectomy, and 10 who underwent open esophagectomy, for locally advanced unresectable esophageal cancer after induction therapy between March 2007 and July 2020.

RESULTS

The two groups did not significantly differ in patient background. Median total and thoracic surgical times were both significantly longer for open esophagectomy than for thoracoscopic esophagectomy. Median blood loss was also greater in the open esophagectomy group than in the thoracoscopic esophagectomy group. The thoracoscopic esophagectomy group also had significantly shorter median chest drain duration; and lower C-reactive protein levels on the second and third postoperative days. The two groups did not significantly differ in total complications or postoperative hospital stay.

CONCLUSIONS

Thoracoscopic esophagectomy is as safe and feasible as open esophagectomy for conversion surgery after induction therapy for locally advanced unresectable esophageal squamous cell carcinoma.

Impact of reduced skeletal muscle volume on clinical outcome after esophagectomy for esophageal cancer: A retrospective study

The aim of the study was to clarify the impact of reduced skeletal muscle volume on the morbidity of patients who underwent esophagectomy for esophageal cancer.Malnutrition and reduced skeletal muscle volume, that is, presarcopenia, are reportedly associated with a high frequency of postoperative complications after esophagectomy. However, it remains unclear whether the reduction of skeletal muscle volume following esophagectomy may affect clinical outcomes including pneumonia occurred beyond the preoperative period.From February 2009 to June 2015, in 123 patients, we retrospectively evaluated the postoperative changes of the psoas muscle index (PI) on computed tomography and assessed their impact on the incidence of pneumonia after esophagectomy.There was a significant reduction in the PI 6 months after surgery compared to the preoperative value. The incidence of pneumonia as of 6 months after surgery was 23.6%, which was higher in patients of advanced age (P = .02), those with a lower body mass index (P = .02), and those with a greater reduction of PI during 6 months after surgery (P = .03). It was not associated with preoperative nutritional data, pulmonary function, operative procedure, and preoperative PI. Multivariate analysis demonstrated that age and postoperative PI reduction were independently associated with the incidence of pneumonia 6 months after surgery (hazard ratio [HR] = 2.92, 95% confidence interval [CI] 1.16-7.32, P = .02; HR = 3.25, 95% CI 1.15-9.15, P = .03, respectively). Patients with pneumonia 6 months after surgery had significantly poorer overall survival than those without pneumonia at that time.Postoperative reduction of skeletal muscle volume was independently associated with the occurrence of pneumonia beyond the preoperative period, which might indicate the importance of a postoperative nutritional support after perioperative period in esophageal cancer patients.

[A Case of Sigmoid Colon Cancer with Locally Advanced Infiltration Curatively Resected after CapeOX Therapy]

A 68-year-old man presented with malaise and abdominal swelling.Lower gastrointestinal endoscopy revealed a type 2 circumferential sigmoid colon cancer.Computed tomography suggested the cancer infiltrating bladder and abdominal wall with abscess.Because of locally advanced infiltration, the patient was treated with capecitabine plus oxaliplatin(CapeOX) plus bevacizumab therapy after loop-colostomy.After 2 courses of chemotherapy, a CT revealed tumor reduction and increased abscess, which was punctured drainage.After 4 courses of chemotherapy, a CT revealed abscess reduction, we tried to operation.Sigmoidectomy with combined resection of abdominal wall and bladder total hysterectomy and fascia lata grafting were performed.The pathological diagnosis was tub1, T4b, ly2, v2, PN0, N0, M0, Stage II, pR0, Grade I a.We reported a case of curative resection of locally advanced sigmoid colon cancer treated with combined resection of bladder and abdominal wall after CapeOX therapy.

[A Case of a Bulky Axillary Ectopic Breast Cancer Which Successfully Resected after Chemotherapy(Docetaxel)]

A 78-year-old woman presented with a right axillary mass.With an incisional biopsy a diagnosis of invasive ductal carcinoma was achieved.In the whole body search, any primary focus including the breast was unclear, advanced occult breast cancer with supraclavicular lymph node metastases was diagnosed.Administration of 3 courses of docetaxel achieved disappearance of supraclavicular lymph node and reduction of an axillary mass.Right axillary lymph node dissection could be successfully performed.Pathological report showed a right ectopic cancer with right axillary lymph node metastases.The patient has been well without any relapse for 3 years.

[Prolonged Survival Achieved with Surgical Resection and Multidisciplinary Therapy for Acinar Cell Carcinoma of the Pancreas with Liver Metastases]

We report 2 cases of prolonged survival achieved with surgical resection and multidisciplinary therapy for acinar cell carcinoma of the pancreas with liver metastases.Case 1: The patient was a 55-year-old woman.She presented with upper right abdominal pain and anemia.We diagnosed a tumor originating from the pancreas and multiple liver metastases.To avoid death caused by bleeding from the tumor, we performed pancreaticoduodenectomy and right-hemi hepatectomy, and a rapid diagnosis of acinar cell carcinoma of the pancreas was confirmed intraoperatively.After the hospital discharge, we administered hepatic intra-arterial chemotherapy and performed microwave ablation for the remnant liver metastases.Additionally, systemic chemotherapy with gemcitabine was administered; however, multiple metastases of the lung and liver became uncontrollable and she died 2 and half years postoperatively.Case 2: The patient was a 42-year-old woman.Through a medical checkup, gastric varix and elevated tumor markers were detected.The examination revealed a tumor at the tail of the pancreas and liver metastasis.We performed distal pancreatomy and partial liver resection.The pathological diagnosis was acinar cell carcinoma and liver metastasis.We administered adjuvant chemotherapy by using gemcitabine and achieved 5 years of relapse-free survival.The prognosis of ACC is better than that for PDAC.However, prognosis of unresectable cases is still unfavorable.Therapeutic strategies including aggressive surgical resection for metastatic ACC are worthy of consideration.

Weekly paclitaxel therapy for gastric cancer in patients with renal dysfunction: A case report

A 57-year-old woman was admitted to National Defense Medical College hospital for treatment of gastric cancer with pyloric stenosis. She had been diagnosed with chronic kidney disease (CKD) 10 years prior, but received no hemodialysis. Because of peritoneal dissemination, a palliative distal gastrectomy was performed. In consideration of renal dysfunction, we decided for chemotherapy with paclitaxel, but not S-1 plus cisplatin regimen which is renal toxic agents. On the 29th postoperative day, chemotherapy using paclitaxel was initiated at a dose of 80 mg/m². Paclitaxel was administered weekly on days 1, 8, and 15 on a 28-day cycle. The patient tolerated 13 courses of this treatment without any severe adverse effect, such as exacerbation of renal function. Despite the gradual increase in the level of tumor markers, metastases were not detected via radiography during the clinical course. Moreover, renal function was maintained for the duration of the clinical course. To date, standard chemotherapeutic treatment for patients with CKD has not been established. We conclude that weekly paclitaxel is a suitable treatment regimen for patients with renal failure requiring chemotherapy for advanced gastric cancer.

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In Japan, the standard therapy for unresectable advanced gastric cancer is S-1 and cisplatin combination chemotherapy. However, the pharmacodynamics of these agents in patients with renal dysfunction remains unclear.

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We herein present a case of chronic kidney disease (CKD) in which the patient was safely given paclitaxel to treat gastric cancer with peritoneal dissemination.

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Weekly paclitaxel therapy is feasible and effective for patients with advanced gastric cancer and renal impairment.

Successful laparoscopic repair of an incarcerated Bochdalek hernia associated with increased intra-abdominal pressure during use of blow gun: A case report

BACKGROUND

Bochdalek hernia is a congenital diaphragmatic hernia, and adult cases are rare, with a reported frequency of 0.17%-6% among all diaphragmatic hernias.

PRESENTATION OF CASE

A 78-year-old man was referred to our hospital with a sudden onset of whole abdominal pain after playing with a blow gun. Chest radiography and computed tomography revealed diaphragmatic hernia with the small intestine. We therefore diagnosed him with an incarcerated Bochdalek hernia associated with increased intra-abdominal pressure during use of blow gun. Laparoscopic repair was performed. The omentum, transverse colon, and small intestine were located in the left thoracic cavity, without ischemic change. After placing the herniated organs into the abdominal cavity, we performed a primary closure of the diaphragmatic defect with interrupted non-absorbable sutures.

DISCUSSION

It is generally recommended that all adult Bochdalek hernia patients undergo surgical repair to prevent life-threatening complications due to incarceration. Recently, laparoscopic techniques for repair the hernia have gained popularity, especially in elective cases. In our case, we could successfully perform emergency laparoscopic repair, as it is associated with a shorter inpatient hospitalization period.

CONCLUSION

An incarcerated Bochdalek hernias associated with increased intra-abdominal pressure is an uncommon clinical finding in an adult, and laparoscopic repair of an incarcerated Bochdalek hernia is safe, feasible, and an excellent option as it is minimally invasive.

In vivo evaluation of a modified linear stapling device designed to facilitate accurate pathologic examination of the surgical margin

BACKGROUND

Microscopic involvement of the resection margin could influence the long-term outcome of patients undergoing curative surgery for gastric cancer. Linear staplers, commonly used for gastrectomies, are often equipped with three lines of staples on either side of the resection line. Although multiple lines of staples reinforce closure of the gastric or intestinal stump, they could hinder accurate histopathologic evaluation of the surgical margin of the resected specimen.

METHODS

We modified a linear stapling device by removing one line (stapler E2) or two lines (stapler E1) of staples on the specimen side, and attempted to dissect a silicon film and then the stomach from a porcine model using the stapling device and examined the distances between the cutting edge and the nearest staple line.

RESULTS

The distance between the cutting edge and the staple line for stapler E1 was significantly greater than the distance between the cutting edge and the nearest staple line for stapler E2 or the control device. Consequently, specimens of exemplary quality were available for pathologic examination of the surgical margin. Moreover, the lack of multiple layers of staples did not result in contamination of the abdominal cavity with gastric juice during laparoscopic procedures in the porcine model.

CONCLUSIONS

Stapler E1 is safe and could be useful for the pathologic evaluation of the true surgical margin.

Efficacy of totally laparoscopic distal gastrectomy for gastric cancer in elderly patients

Elderly patients are often considered as high-risk for major abdominal surgery due to reduced functional reserve and increased comorbidities. We herein evaluated the efficacy of totally laparoscopic distal gastrectomy (TLDG) in elderly patients with gastric cancer by measuring the postoperative systemic responses and postoperative analgesic consumption. A total of 102 patients with gastric cancer [57 who underwent TLDG and 45 who underwent laparoscopy-assisted distal gastrectomy (LADG)] were enrolled in this study. The patients were classified as elderly (aged ≥75 years) and non-elderly (aged <75 years) groups. The surgical outcome and postoperative analgesic consumption were evaluated. The elderly group exhibited a higher incidence of comorbidities and a longer postoperative hospital stay compared with those of younger patients, although there was no difference in the incidence of postoperative complications. In addition, the total consumption of additional analgesics until postoperative day 5 in patients who underwent TLDG was significantly lower compared with that in patients who underwent LADG in the elderly group; there was no such difference in the non-elderly group. The results suggested that TLDG was better for the management of postoperative pain in elderly patients with gastric cancer, who exhibit the highest mortality rates in the adult surgical population.

Pneumatosis intestinalis with obstructing intussusception: A case report and literature review

Pneumatosis intestinalis (PI) often represents a benign condition that should not be considered as an argument for surgery. We report a patient with PI and obstructing intussusception who underwent urgent colectomy and review the literatures regarding PI with intussusception. A 20-year-old man presented at our hospital with a 3-d intermittent lower abdominal pain history. He underwent steroid therapy for membranoproliferative glomerulonephritis for 4 years. Computed tomography revealed ascending colon intussusception with air within the wall. Intraoperative colonoscopy revealed numerous soft polypoid masses with normal overlying mucosa and right hemicolectomy was performed. Histological examination of colonic wall sections revealed large cysts in the submucosal layer. The pathological diagnosis was PI. Nine cases of intussusception associated with primary PI have been reported. Although primary PI often represents a benign condition that should not be considered as an argument for surgery, if the case involves intussusception and obstruction, emergent laparotomy should be considered.

Laparoscopic jejunostomy for obstructing upper gastrointestinal malignancies

The aim of this study was to describe a minimally invasive laparoscopic jejunostomy (Lap-J) technique for obstruction due to upper gastrointestinal malignancies and evaluate the nutritional benefit of Lap-J during neoadjuvant chemotherapy (NAC) in cases with obstructing esophageal cancer. Under general anesthesia, the jejunum 20-30 cm distant from the Treitz ligament was pulled out through an extended umbilical laparoscopic incision and a jejunal tube was inserted to 30 cm. The loop of bowel was gently returned to the abdomen and the feeding tube was drawn through the abdominal wall via the left lower incision. The jejunum was then laparoscopically sutured to the anterior abdominal wall. Lap-J was performed in 26 cases. The median operative time was 82 min. The postoperative course was uneventful. Lap-J prior to NAC was not associated with a decrease in body weight or serum total protein during NAC, compared with patients who received NAC without Lap-J. This minimally invasive jejunostomy technique may be particularly useful in patients in whom endoscopic therapy is not feasible due to obstruction from upper gastrointestinal malignancies.

Laparoscopic resection of a huge retroperitoneal cystic lymphangioma after successful reduction of tumor size with a double balloon catheter

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We present a rare case of huge retroperitoneal cystic lymphangioma, diagnosed radiologically.

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The lymphangioma was successfully resected laparoscopically after aspiration using a SAND balloon catheter.

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Our case demonstrates the feasibility of minimally invasive laparoscopic resection of such lesions.

Introduction

Retroperitoneal cystic lymphangiomas are rare. We report a case of retroperitoneal huge cystic lymphangioma that was successfully aspirated the cyst’s contents with double balloon catheter and excised laparoscopically.

Presentation of case

A 34-year-old man was admitted to our hospital with low-grade fever and abdominal pain that had lasted for 1 week. Abdominal computed tomography and magnetic resonance imaging showed a fluid-filled multilocular mass measuring 13.5 cm in diameter around the tail of the pancreas, which was diagnosed as a retroperitoneal cystic lymphangioma. We successfully excised the tumor by laparoscopic distal pancreatosplenectomy. We punctured and aspirated the tumor with a double-balloon catheter to decrease the tumor’s size without spilling the tumor content. Cytology showed no malignant cells, and histopathological examination confirmed cystic lymphangioma. No recurrence was noted on radiographic imaging 10 months postoperatively.

Discussion and conclusion

Laparoscopic treatment for retroperitoneal huge cystic lymphangioma is feasible, and the double balloon catheter is useful for reducing the tumor volume.

Influence of experimental esophageal acidification on sleep bruxism: a randomized trial

The aim of this cross-over, randomized, single-blinded trial was to examine whether intra-esophageal acidification induces sleep bruxism (SB). Polysomnography with electromyogram (EMG) of masseter muscle, audio-video recording, and esophageal pH monitoring were performed in a sleep laboratory. Twelve healthy adult males without SB participated. Intra-esophageal infusions of 5-mL acidic solution (0.1 N HCl) or saline were administered. The frequencies of EMG bursts, rhythmic masticatory muscle activity (RMMA) episodes, grinding noise, and the RMMA/microarousal ratio were significantly higher in the 20-minute period after acidic infusion than after saline infusion. RMMA episodes including SB were induced by esophageal acidification. This trial is registered with the UMIN Clinical Trials Registry, UMIN000002923.

ABBREVIATIONS

ASDA, American Sleep Disorders Association; EMG, electromyogram; GER, gastroesophageal reflux; LES, lower esophageal sphincter; NREM, non-rapid eye movement; REM, rapid eye movement; RMMA, rhythmic masticatory muscle activity; SB, sleep bruxism; SD, standard deviation; UES, upper esophageal sphincter.

Effects of glutamate receptor agonist on extracellular glutamate dynamics during moderate cerebral ischemia

We performed real-time monitoring of the extracellular glutamate dynamics in the rat striatum in vivo using the microdialysis electrode technique, during an experimental penumbral condition of moderate global cerebral ischemia and activated glutamate receptors. The local cerebral blood flow (CBF) was measured with a laser-Doppler probe. One minute after bilateral common carotid artery occlusion (BCAO), CBF was reduced to approximately 60% of the pre-ischemic value and it remained at this level during the period of occlusion. After BCAO, a transient depolarization and a transient increase in extracellular glutamate concentration ([Glu]e) were seen. In other rats, 500 microM N-methyl-D-aspartate (NMDA) was locally micro-transfused for 30 min prior to BCAO. Upon induction of BCAO, an anoxic depolarization-like depolarization and a gradual increase in [Glu]e that continued over the duration of BCAO were seen. After BCAO was terminated, the direct current (DC) rapidly recovered to the basal level, while [Glu]e gradually decreased to the basal level. In rats that were locally micro-transfused with 500 microM Kainate prior to BCAO, DC and [Glu]e did not differ significantly from control. Pretreatment with MK-801 prior to NMDA treatment completely inhibited the NMDA-induced changes in DC and [Glu]e. Pretreatment with NBQX prior to NMDA treatment did not inhibit the NMDA-induced changes in DC and [Glu]e. Consequently, we found that activation of NMDA receptors by elevated [Glu]e exerts an important effect on [Glu]e dynamics in the spreading stroke region very early in the acute stage of cerebral ischemia in vivo.

Oxygen-independent real-time monitoring of distinct biphasic glutamate release using dialysis electrode in rat striatum during anoxia: in vivo evaluation of glutamate release and reversed uptake

Using a dialysis electrode, previous studies showed a clear biphasic release of glutamate during anoxia and ischemia. In this study, we examined two hypotheses: (1) glutamate is of vesicular origin and its release is thus Ca2+- and ATP-dependent in the first phase, while in the second phase glutamate is derived primarily from the metabolic pool, and (2) reversed glutamate uptake, due to electrogenic stoichiometry, produces the second phase during anoxic insult in the rat brain. A dialysis electrode continuously perfused with glutamate oxidase and ferrocene-conjugated bovine serum albumin (BSA) optimized the time resolution of monitoring, allowing quantitative oxygen-independent, real-time measurement of the extracellular glutamate concentration ([Glu]e) during anoxia. [Glu]e dynamics were analyzed during anoxia by combining the dialysis electrode with focal microinjection of substances inducing glutamate release. Following anoxia in the rat brain, a sharp and rapid [Glu]e elevation took place (first phase). The [Glu]e elevation then shifted, continuing a gently sloping rise throughout the anoxic period (second phase). This first phase disappeared with intracranial administration of either Co2+ or omega-conotoxin. The second phase rise increased with focal microinjection of KCl (300 mM, 1 microL) and decreased with NaCl (300 mM, 1 microL), ultimately reaching a plateau in both cases. Preloading with a novel glutamate transporter inhibitor (tPDC) decreased both the first and second phases of [Glu]e elevation. This dialysis electrode system provides data supporting in vivo evidence that the peak of the first phase of [Glu]e elevation is derived from the "neurotransmitter pool," while the second phase is derived from the neuronal and glial "metabolic pool," which is, at least, partly related to a "reversed uptake" mechanism in the anoxic rat brain.

Transient in vivo membrane depolarization and glutamate release before anoxic depolarization in rat striatum

Increased extracellular glutamate ([GLU]e), under the condition of cerebral ischemia, anoxia or hypoxia, has been recognized as being associated with neuronal cell damage and death. We performed real-time monitoring of [GLU]e dynamics in vivo in the rat striatum during systemic acute anoxia or hypoxia, as well as monitoring the direct current potential (DC) and cerebral blood flow (CBF). Adult Wistar rats were orotracheally intubated and artificially ventilated with room air. A microdialysis electrode, temperature sensor probe, DC microelectrode and laser Doppler probe were then implanted. The inspired gas was changed to 100% N(2) (anoxia), or to 3, 5 or 8% O(2) (remainder N(2)) (hypoxia). With 100% N(2), distinct biphasic [GLU]e elevations were observed. With 3% O(2), a transient [GLU]e increase was seen before anoxic depolarization (AD). With 5% O(2), however, the start of the transient [GLU]e increase was significantly delayed. Anoxia-induced depolarization started at about 100 s. The 3% O(2)-induced transient depolarization and AD began at nearly the same time as the transient and AD-induced increase in [GLU]e. Similarly, the responses to 5% O(2) showed significant delays in the transient depolarization and AD-induced increase in [GLU]e. CBF during 3 or 5% O(2) hypoxic insult was consistently maintained above the control level, i.e., prior to cardiac arrest. Our new dialysis electrode method employing both GOX and ferrocene-conjugated bovine serum albumin allowed evaluation of transient [GLU]e dynamics in the early phase of severe hypoxia in vivo.

Anticancer activity of morphine and its synthetic derivative, KT-90, mediated through apoptosis and inhibition of NF-kappaB activation

We recently reported that morphine inhibits growth of various human cancer cell lines (IC50/2.7-8.8 mM). We then extended the study using newly synthesized morphine derivatives, such as KT-90 and KT-87, which are analgesics 5 times more potent than morphine. KT-90 was found to inhibit growth of human cancer cell lines (IC50/42-70 microM) up to 80 times more potently than morphine. As for mechanisms of action, KT-90 and morphine induced apoptosis, and inhibited tumor necrosis factor alpha (TNF-alpha) gene expression induced by tumor promoters, okadaic acid and 12-O-tetradecanoylphorbol-13-acetate, associated with reduction of NF-kappaB DNA binding activity. This paper provides evidence that KT compounds confirmed the presence of anticancer activity of morphine in addition to its analgesic action.

[Ligand recognition in the opioid receptors by modeling methods and the design of opioids]

For understanding the three-dimensional mechanisms that control potency and selectivity of the ligand binding at the atomic level, we have analysed opioid receptor-ligand interaction based on the receptor's 3D model. The analyses of the interactions of some opioid ligands with the predicted ligand binding sites are consistent with the results of the affinity labeling experiments. On the basis of the three-dimensional structures of the putative binding sites in the opioid receptors, a potent kappa agonist KT-95 was designed in our laboratory.

Real-time monitoring of the effects of normothermia and hypothermia on extracellular glutamate re-uptake in the rat following global brain ischemia

Brain hypothermia during ischemia may have a neuroprotective effect on pathological and functional outcomes in vivo. Although a microdialysis study demonstrated that hypothermia decreases glutamate release into the extracellular space, the issue of whether this suppression of the glutamate elevation normally accompanying ischemia is attributable to inhibition of intra-ischemic release or acceleration of post-ischemic re-uptake was not addressed. Recently, we established a real-time method for monitoring glutamate levels in extracellular space, utilizing a dialysis electrode. This method allows detailed analysis of the in vivo dynamics of biphasic glutamate elevation in the extracellular space during the intra-ischemic period and post-ischemic re-uptake. The present results show that post-ischemic hypothermia has little effect on the initial glutamate release, but remarkably enhances post-ischemic glutamate re-uptake.

Ligand recognition in mu opioid receptor: experimentally based modeling of mu opioid receptor binding sites and their testing by ligand docking

For three-dimensional understanding of the mechanisms that control potency and selectivity of the ligand binding at the atomic level, we have analysed opioid receptor-ligand interaction based on the receptor's 3D model. As a first step, we have constructed molecular models for the multiple opioid receptor subtypes using bacteriorhodopsin as a template. The S-activated dihydromorphine derivatives should serve as powerful tools in mapping the three-dimensional structure of the mu opioid receptor, including the nature of the agonist-mediated conformational change that permits G protein-coupling to "second messenger' effector molecules, and in identifying specific ligand-binding contacts with the mu opioid receptor. The analyses of the interactions of some opioid ligands with the predicted ligand binding sites are consistent with the results of the affinity labeling experiments.

Pharmacological characterization of KT-90 using cloned mu-, delta- and kappa-opioid receptors

We analyzed the pharmacological characteristics of (-)-3-acetyl-6 beta-acetylthio-N-cyclopropylmethyl-normorphine (KT-90) using Chinese hamster ovary (CHO) cells expressing cloned rat mu-, delta- and kappa-opioid receptors. KT-90 displaced the specific binding of the following radiolabeled ligands selective to the mu-, delta- and kappa-opioid receptors, [3H][D-Ala2,MePhe4,Gly(ol)5]enkephalin (DAMGO), [3H][D-Pen2,D-Pen5]enkephalin (DPDPE), [3H] (+)-(5 alpha, 7 alpha, 8 beta)-N-methyl-N-[7-(1-pyrrolidinyl) l-oxaspiro-(4,5)dec-8-yl]benzeneacetamide (U69,593), with Ki values of 3.3 +/- 0.7, 22.8 +/- 1.5 and 1.9 +/- 0.3 nM, respectively In CHO cells expressing the mu-, delta- and kappa-opioid receptors, KT-90 inhibited forskolin (10 microM)-induced cyclic AMP accumulation in a concentration-dependent manner with IC50 values of 2337 +/- 750, 17.3 +/- 4.6 and 2.0 +/- 0.1 nM, respectively. The maximal inhibitory effects of KT-90 in the cells expressing mu-, delta- and kappa-opioid receptors were significantly lower than those of the type-selective agonists DAMGO, DPDPE and U69,593, respectively. These results indicated that KT-90 acts as a partial agonist on mu-, delta- and kappa-opioid receptors. KT-90 (10 and 100 nM), when added with morphine, produced a rightward shift of the concentration-response curve of morphine to inhibit the cyclic AMP accumulation in CHO cells expressing mu-, but not delta- or kappa-, opioid receptors. This finding is consistent with the findings that lower doses of KT-90 antagonize morphine analgesia in vivo.

Some pharmacological properties of a newly synthesized 3-acetoxy-6 beta-acetylthio-10-oxo-N-cyclopropylmethyl-dihydronormorphine (KT-95)

The pharmacological properties of a newly synthesized 3-acetoxy-6 beta-acetylthio-10-oxo-N-cyclopropylmethyl-dihydronormorphine (KT-95) were examined. This compound, as well as (-)-3-acetyl-6 beta-acetylthio-N-cyclopropylmethylnormorphine (KT-90) and morphine, inhibited the twitch response to electrical stimulation of the guinea-pig ileal preparation that contains mu- and kappa-receptors. The inhibitory effect of KT-95 was about 17 times more potent than morphine, and about 4 times more potent than KT-90. In the guinea-pig ileal preparation, KT-95 behaved as a mu-antagonist against morphine in the presence of norbinaltorphimine (3 x 10(-8) M). In the rabbit vas deferens, containing kappa-opioid receptors, KT-95 inhibited the twitch response to electrical stimulation in a concentration-dependent manner. Norbinaltorphimine concentration-dependently caused parallel rightward shifts of the concentration-response curves to KT-95 in the guinea-pig ileum and in the rabbit vas deferens after electrical stimulation, suggesting that KT-95 behaved as an agonist for the kappa-opioid receptor. In the mouse vas deferens, that contains delta-receptors. KT-95 behaved also as a delta-antagonist against Leu-enkephalin in the presence of norbinaltorphimine. KT-95, KT-90 and morphine were examined for their potencies in displacing the specific binding of [3H]naloxone (mu-selective ligand), [3H]U69593 (kappa-selective ligand), and [3H]D-Ala2-D-Leu5-enkephalin (delta-selective ligand) to synaptosomal fractions from rat brain. Although KT-95 had a higher nonselective affinity to mu-receptors than KT-90 and morphine, the affinity of KT-95 to kappa-receptors was about 18 times higher than that of morphine, and about 5 times higher than that of KT-90. In the acetic acid-induced writhing test, subcutaneously injected KT-95 was more potent than morphine. Furthermore, the analgesic effect, induced by KT-95 (0.062 mumol/kg, s.c.), was abolished by simultaneous administration of norbinaltorphimine (0.020 mumol/mouse, s.c.), suggesting that the analgesic action of KT-95 is mediated through the kappa-opioid receptor. In the pressure test, KT-95 was 20.17 times more potent than morphine. The analgesic action, induced by KT-95 (2.05 mumol/kg, s.c.), was also in this test abolished by simultaneous administration of norbinaltorphimine (0.14 mumol/rat, s.c.), suggesting that this action of KT-95 is mediated through the kappa-opioid receptor. These results indicate that KT-95 behaves as a kappa-agonist with mu- and delta-antagonistic activities, and suggest that analgesia, induced by KT-95, is mainly mediated through kappa-receptors.

Production and characterization of an anti-chicken transferrin

Several lines of recent evidence have suggested that transferrin plays a significant role in tissue interaction or morphogenesis at early stages of embryo development. In the present study, an anti-chicken transferrin antibody was produced and its basic characteristics were clarified as a basis for use in further studies. An antiserum termed Toraji 3 was raised against chicken transferrin and purified into IgG and ligand-affinity-purified fractions. These three preparations of the antibody gave an intense immunohistochemical signal in visceral yolk sac and developing liver, both of which are known to be major producers of transferrin in early development. In immunoblot analysis, these three preparations detected 70-kDa transferrin, whereas the ligand-affinity-purified preparation showed higher specificity. It was also demonstrated by enzyme-linked immunosorbent assay and immunoblotting that Toraji 3 antibody bound preferentially to chicken transferrin and showed a negligible binding to human transferrin.

Comparison between diurnal distribution of onset of infarction in patients with acute myocardial infarction and circadian variation of blood pressure in patients with coronary artery disease

We analyzed the diurnal distribution of the onset of infarction in 636 patients with acute myocardial infarction (MI) and compared it with the circadian variation of blood pressure in 57 patients with coronary artery disease (CAD). In addition, we studied the modification of the circadian blood pressure variation during treatment with antianginal medications in 20 patients with CAD. A marked diurnal periodicity (p < 0.05) was observed for the onset of MI, with peaks seen in the late morning, late evening, and very early morning. The blood pressure in the patients with CAD was elevated in the morning, reduced in the late evening, and was the lowest in the very early morning. The peaks of onset of infarction temporally corresponded to the characteristic feature of blood pressure profile observed in the patients with CAD, that is, the morning rise, the late evening decline, and the very early morning reduction. Antianginal medications significantly reduced the blood pressure, not only during the day (p < 0.02) but also at night (p < 0.05). These observations suggest that the decline in blood pressure, as well as the morning surge in blood pressure, may be closely related to the onset of MI. Therefore, when treating patients with CAD with antianginal medications which can potentially reduce blood pressure, the effects on the circadian variation of blood pressure should be considered.

Molecular structure of (-)-3-acetyl-6 beta-(acetylthio)-N-(cyclopropyl-methyl) normorphine and its 14-hydroxy congeners

The stereochemistry of the title compound 3 was confirmed by X-ray analysis. The 6-acetylthio derivatives with an OH group at C-14 were also designed and synthesized.