Nivolumab receptor occupancy on effector regulatory T cells predicts clinical benefit

Immune checkpoint inhibitor discovery represents a turning point in cancer treatment. However, the response rates of solid tumors remain ~10%-30%; consequently, prognostic and immune-related adverse event (irAE) predictors are being explored. The programmed cell death protein 1 (PD-1) receptor occupancy (RO) of PD-1 inhibitors depends on the number of peripheral blood lymphocytes and their PD-1 expression levels, suggesting that the RO may be related to efficacy and adverse events. As PD-1 inhibition affects each T-cell subset differently, the RO of each cell population must be characterized. However, relevant data have not been reported, and the prognostic relevance of this parameter is not known. In this study, we aimed to clarify the association between the nivolumab RO in each T-cell population and patient prognosis and reveal the development of irAEs in nivolumab-treated patients. Thirty-two patients were included in the study, and the mean follow-up period was 364 days. The nivolumab RO on effector regulatory T cells (eTregs) was significantly lower in the group that presented clinical benefits, and a significant negative association was observed between PD-1 occupancy on eTregs and all-cause mortality. The results suggest that the nivolumab RO on eTregs may be a prognostic factor in PD-1 inhibitor therapy, implying that the inhibition of PD-1/PD-ligand 1 (PD-L1) signaling on eTregs may attenuate antitumor effects.

Butyricimonas is a key gut microbiome component for predicting postoperative recurrence of esophageal cancer

BACKGROUND

Recently, intestinal bacteria have attracted attention as factors affecting the prognosis of patients with cancer. However, the intestinal microbiome is composed of several hundred types of bacteria, necessitating the development of an analytical method that can allow the use of this information as a highly accurate biomarker. In this study, we investigated whether the preoperative intestinal bacterial profile in patients with esophageal cancer who underwent surgery after preoperative chemotherapy could be used as a biomarker of postoperative recurrence of esophageal cancer.

METHODS

We determined the gut microbiome of the patients using 16S rRNA metagenome sequencing, followed by statistical analysis. Simultaneously, we performed a machine learning analysis using a random forest model with hyperparameter tuning and compared the data obtained.

RESULTS

Statistical and machine learning analyses revealed two common bacterial genera, Butyricimonas and Actinomyces, which were abundant in cases with recurrent esophageal cancer. Butyricimonas primarily produces butyrate, whereas Actinomyces are oral bacteria whose function in the gut is unknown.

CONCLUSION

Our results indicate that Butyricimonas spp. may be a biomarker of postoperative recurrence of esophageal cancer. Although the extent of the involvement of these bacteria in immune regulation remains unknown, future research should investigate their presence in other pathological conditions. Such research could potentially lead to a better understanding of the immunological impact of these bacteria on patients with cancer and their application as biomarkers.

Non-classical Monocytes Enhance the Efficacy of Immune Checkpoint Inhibitors on Colon Cancer in a Syngeneic Mouse Model

BACKGROUND/AIM

The response rate to immune checkpoint inhibitors (ICIs) is approximately 10%-30% and only in a few cancer types. In the present study, we determined whether non-classical monocytes (NCMs) could enhance ICI efficacy in colon cancer using a syngeneic mouse model.

MATERIALS AND METHODS

The MC38 C57BL/6 mouse colon cancer model was used. Cells collected from the bone marrow of C57BL/6 mice were cultured, and NCMs were fractionated by cell sorting and administered via the tail veins to the mice implanted with MC38 cells. The anti-mouse PD-L1 antibody was administered three times, and tumor volume and overall survival were observed.

RESULTS

More tumors were eradicated and more complete response occurred, after cotreatment with ICIs and NCMs than after treatment with ICIs alone. Moreover, no efficacy was observed when NCMs were administered alone.

CONCLUSION

NCMs enhance ICI efficacy. The underlying mechanisms and clinical applications will be studied in the future.

Novel quantitative immunohistochemical analysis for evaluating PD-L1 expression with phosphor-integrated dots for predicting the efficacy of patients with cancer treated with immune checkpoint inhibitors

Introduction

Programmed cell death ligand 1 (PD-L1) expression in tumor tissues is measured as a predictor of the therapeutic efficacy of immune checkpoint inhibitors (ICIs) in many cancer types. PD-L1 expression is evaluated by immunohistochemical staining using 3,3´-diaminobenzidine (DAB) chronogenesis (IHC-DAB); however, quantitative and reproducibility issues remain. We focused on a highly sensitive quantitative immunohistochemical method using phosphor-integrated dots (PIDs), which are fluorescent nanoparticles, and evaluated PD-L1 expression between the PID method and conventional DAB method.

Methods

In total, 155 patients with metastatic or recurrent cancer treated with ICIs were enrolled from four university hospitals. Tumor tissue specimens collected before treatment were subjected to immunohistochemical staining with both the PID and conventional DAB methods to evaluate PD-L1 protein expression.

Results

PD-L1 expression assessed using the PID and DAB methods was positively correlated. We quantified PD-L1 expression using the PID method and calculated PD-L1 PID scores. The PID score was significantly higher in the responder group than in the non-responder group. Survival analysis demonstrated that PD-L1 expression evaluated using the IHC-DAB method was not associated with progression-free survival (PFS) or overall survival (OS). Yet, PFS and OS were strikingly prolonged in the high PD-L1 PID score group.

Conclusion

Quantification of PD-L1 expression as a PID score was more effective in predicting the treatment efficacy and prognosis of patients with cancer treated with ICIs. The quantitative evaluation of PD-L1 expression using the PID method is a novel strategy for protein detection. It is highly significant that the PID method was able to identify a group of patients with a favorable prognosis who could not be identified by the conventional DAB method.

Monocyte subsets associated with the efficacy of anti‑PD‑1 antibody monotherapy

Immune checkpoint inhibitors (ICIs) are among the most notable advances in cancer immunotherapy; however, reliable biomarkers for the efficacy of ICIs are yet to be reported. Programmed death (PD)-ligand 1 (L1)-expressing CD14+ monocytes are associated with shorter overall survival (OS) time in patients with cancer treated with anti-PD-1 antibodies. The present study focused on the classification of monocytes into three subsets: Classical, intermediate and non-classical. A total of 44 patients with different types of cancer treated with anti-PD-1 monotherapy (pembrolizumab or nivolumab) were enrolled in the present study. The percentage of each monocyte subset was investigated, and the percentage of cells expressing PD-L1 or PD-1 within each of the three subsets was further analyzed. Higher pretreatment classical monocyte percentages were correlated with shorter OS (r=-0.32; P=0.032), whereas higher non-classical monocyte percentages were correlated with a favorable OS (r=0.39; P=0.0083). PD-L1-expressing classical monocytes accounted for a higher percentage of the total monocytes than non-classical monocytes with PD-L1 expression. In patients with non-small cell lung cancer (NSCLC), a higher percentage of PD-L1-expressing classical monocytes was correlated with shorter OS (r=-0.60; P=0.012), which is similar to the observation for the whole patient cohort. Comparatively, higher percentages of non-classical monocytes expressing PD-L1 were significantly associated with better OS, especially in patients with NSCLC (r=0.60; P=0.010). Moreover, a higher percentage of non-classical monocytes contributed to prolonged progression-free survival in patients with NSCLC (r=0.50; P=0.042), with similar results for PD-L1-expressing non-classical monocytes. The results suggested that the percentage of monocyte subsets in patients with cancer before anti-PD-1 monotherapy may predict the treatment efficacy and prognosis. Furthermore, more classical monocytes and fewer non-classical monocytes, especially those expressing PD-L1, are involved in shortening OS time, which may indicate the poor efficiency of anti-PD-1 treatment approaches.

Case Report: Combined pembrolizumab, 5-fluorouracil, and cisplatin therapy were remarkably effective in p16-positive squamous cell carcinoma of unknown primary

Background

Cancer of unknown primary (CUP) is a malignant tumor without a known primary lesion with a frequency of 3-5%. It can be divided into favorable and unfavorable prognosis subsets. While recommended treatments are available for the former group, there is no established treatment for the latter. Here, we report the effective treatment of a 32-year-old woman with p16-positive squamous cell CUP with pembrolizumab plus 5-fluorouracil and cisplatin therapy.

Case presentation

A 32-year-old woman presented with metastatic lesions in the liver, lung, bone, cervical region, abdominal region, and pelvic lymph nodes. She was diagnosed with p16-positive squamous cell carcinoma of unknown primary origin. The patient received pembrolizumab plus 5-fluorouracil and cisplatin therapy, which markedly reduced the metastasis and improved her Eastern Cooperative Oncology Group performance status after two courses.

Conclusion

This case report highlights the potential of pembrolizumab plus 5-fluorouracil and cisplatin therapy for treating CUP with an unfavorable prognosis. p16 positivity is worth examining for squamous cell carcinoma of unknown primary origin, and if present, this therapy should be considered a promising treatment option.

Turicibacter and Acidaminococcus predict immune-related adverse events and efficacy of immune checkpoint inhibitor

Introduction

Immune checkpoint inhibitors have had a major impact on cancer treatment. Gut microbiota plays a major role in the cancer microenvironment, affecting treatment response. The gut microbiota is highly individual, and varies with factors, such as age and race. Gut microbiota composition in Japanese cancer patients and the efficacy of immunotherapy remain unknown.

Methods

We investigated the gut microbiota of 26 patients with solid tumors prior to immune checkpoint inhibitor monotherapy to identify bacteria involved in the efficacy of these drugs and immune-related adverse events (irAEs).

Results

The genera Prevotella and Parabacteroides were relatively common in the group showing efficacy towards the anti-PD-1 antibody treatment (effective group). The proportions of Catenibacterium (P = 0.022) and Turicibacter (P = 0.049) were significantly higher in the effective group than in the ineffective group. In addition, the proportion of Desulfovibrion (P = 0.033) was significantly higher in the ineffective group. Next, they were divided into irAE and non-irAE groups. The proportions of Turicibacter (P = 0.001) and Acidaminococcus (P = 0.001) were significantly higher in the group with irAEs than in those without, while the proportions of Blautia (P = 0.013) and the unclassified Clostridiales (P = 0.027) were significantly higher in the group without irAEs than those with. Furthermore, within the Effective group, Acidaminococcus and Turicibacter (both P = 0.001) were more abundant in the subgroup with irAEs than in those without them. In contrast, Blautia (P = 0.021) and Bilophila (P= 0.033) were statistically significantly more common in those without irAEs.

Discussion

Our Study suggests that the analysis of the gut microbiota may provide future predictive markers for the efficacy of cancer immunotherapy or the selection of candidates for fecal transplantation for cancer immunotherapy.

Abstract 6179: Increased circulating PD-L1 expressing CD14 high CD16 negative classical monocytes correlate with poor prognosis in cancer patients treated with PD-1 blockade therapies

Background: Immune checkpoint inhibitors (ICIs), like PD-1 and PD-L1 blockade therapies, are currently considered as one of the most significant breakthroughs in potent cancer immunotherapy. However, many patients are non-responders or develop resistance following an initial response to ICIs. ICIs have no accurate predictive biomarkers. Previously, we showed that increased expression of PD-L1 molecules on CD14+ monocytes was significantly correlated with shorter overall survival (OS) for patients with several cancer types on PD-1 blockade therapies. As monocytes can be further classified into subsets (classical, intermediate, non-classical), we herein investigated the prognostic factors in peripheral blood mononuclear cell (PBMC) subsets and assessed the clinical significance for the PD-L1-expressing subsets of each of these cells including classical, intermediate and non-classical monocyte subsets in patients with various cancer types, along with their clinical implications in PD-1 blockade therapies.

Material and Methods: We evaluated 44 patients (20 with gastric cancer, 17 with non-small cell lung carcinoma, and 7 with esophageal cancer) undergoing PD-L1 blockade therapy (pembrolizumab or nivolumab) for PD-L1 expression levels in classical (CD14high, CD16-), intermediate (CD14high, CD16+), and non-classical (CD14low, CD16+) monocytes measured via flow cytometry before ICI treatment. The percentages of PD-L1+ cells in respective monocyte subsets were compared with respect to different clinicopathological conditions and the association with survival time was assessed.

Results: The number of PD-1 positive cells in CD14+ monocytes was very low (almost <1%). Also, the monocyte subset expressing PD-L1 had a high percentage of classical monocytes, whereas non-classical monocytes expressed less PD-L1. Higher levels of classical monocytes were correlated with shorter OS (P = 0.044), whereas higher levels of non-classical monocytes were correlated with longer OS (P = 0.027). Focusing on non-small cell lung cancer population (N = 17), higher levels of PD-L1-expressing CD14+ monocytes were statistically correlated with shorter OS (P = 0.025). Furthermore, analysis of a subset of monocytes showed that the higher PD-L1-expressing classical monocytes correlated with the shorter OS, suggesting that they predict poor prognosis (P = 0.0095).

Conclusion: Circulating PD-L1-expressing classical monocytes in the peripheral bloods were associated with poor prognosis in patients treated with PD-1 blockade therapies. Among the monocyte subsets, classical monocyte, especially PD-L1-expressing classical monocytes can be a potential biomarker for prognosis in these patients.

Citation Format: Ryotaro Ohkuma, Katsuaki Ieguchi, Makoto Watanabe, Tsubasa Goshima, Rie Onoue, Kazuyuki Hamada, Yutaro Kubota, Atsushi Horiike, Toshiaki Tsurui, Risako Suzuki, Nana Iriguchi, Tomoyuki Ishiguro, Yuya Hirasawa, Hirotsugu Ariizumi, Kiyoshi Yoshimura, Mayumi Tsuji, Yuji Kiuchi, Shinichi Kobayashi, Takuya Tsunoda, Satoshi Wada. Increased circulating PD-L1 expressing CD14 high CD16 negative classical monocytes correlate with poor prognosis in cancer patients treated with PD-1 blockade therapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6179.

A case of bronchial asthma as an immune-related adverse event of pembrolizumab treatment for bladder cancer: A case report

RATIONALE

Bladder cancer is one of the most common cancers worldwide. The anti-programmed cell death protein 1 (PD-1) antibody pembrolizumab, which is an immune checkpoint inhibitor (ICI), has improved survival in bladder cancer. We report a case of bladder cancer that had a high antitumor effect with anti-programmed cell death PD-1 antibody pembrolizumab, an ICI, but asthma occurred an immune-related adverse event (irAE).

PATIENT CONCERNS

A 70-year-old female patient was diagnosed as unresectable bladder cancer who was indicated for ICI treatment.

DIAGNOSIS

After ICI administration as a treatment for bladder cancer, the patient had a grade 3 asthma attack. Cytotoxic T lymphocyte antigen 4 (CTLA-4) in CD4+ FOX3+ T cells was upregulated in the early phase before the development of asthma attacks. Moreover, T-cell immunoglobulin and mucin domain 3 (TIM-3) was upregulated in all memory T cells among CD4+ T cells. However, no change in the expression of TIM-3 was observed in any CD8+ T-cell subtype. In contrast, the proportion of CD161- T helper 17 cell (Th17) cells increased.

INTERVENTIONS

The patient was treated with betamethasone, montelukast, salbutamol nebulization, and a combination of salmeterol (50 μg) and fluticasone (500 μg) (SFC).

OUTCOMES

The patient's wheezing resolved, and her peak flow rate reached 100% of the predicted value; therefore, the patient continued treatment with SFC and montelukast and was discharged from the hospital.

CONCLUSION

Increases in CTLA-4 and TIM-3 expression in CD4+ T cells (not CD8+), as well as an increase in Th17 cells, may reflect asthma-related inflammation activity. Immune-related adverse events during immune checkpoint inhibitor administration may be predictive markers of antitumor efficacy.

Antibiotic Usage Reduced Overall Survival by over 70% in Non-small Cell Lung Cancer Patients on Anti-PD-1 Immunotherapy

BACKGROUND/AIM

There is an increasing use of immunotherapy for non-small cell lung cancer (NSCLC) patients. The present study analysed the effect of antibiotic use on the outcome of NSCLC patients undergoing treatment with anti-programmed cell death-1 (anti-PD-1) immunotherapy.

PATIENTS AND METHODS

This was a retrospective study of 69 NSCLC patients. Eighteen out of 69 patients received antibiotics within 21 days before or within 21 days after start of anti-PD-1 therapy.

RESULTS

Patients treated with anti-PD-1 antibodies receiving antibiotics had greatly decreased objective response rate (ORR), overall survival (OS) and progression-free survival (PFS) compared to those who did not use antibiotics. Multivariate analysis showed that antibiotic treatment of patients on anti-PD-1 antibody therapy was an independent negative predictive factor of PFS; however, it was not a significant independent predictive factor of OS.

CONCLUSION

Use of antibiotics within 21 days before and after anti-PD-1 treatment initiation in patients with NSCLC strongly reduced OS and PFS, suggesting the two treatments should not be combined.

Rare Nivolumab-associated Super Hyper Progressive Disease in Patients With Advanced Gastric Cancer

BACKGROUND/AIM

Rapid tumor growth after administration of immune checkpoint inhibitors is designated hyper progressive disease (HPD). In this study, besides the conventional HPD category, we proposed the "super HPD" category where the disease is naturally rapidly growing.

PATIENTS AND METHODS

Patients treated for advanced gastric cancer with irinotecan or nivolumab as a third-line treatment were retrospectively compared.

RESULTS

Eighteen and 26 patients were treated with irinotecan or nivolumab, respectively. There were 3 HPD cases (16.7%) in the irinotecan group, 6 cases (23.1%) in the nivolumab group, and the frequency of HPD was not significantly different. Two cases satisfied the super HPD definition only in the nivolumab group. When one of them was analyzed immunologically, the number of regulatory T cells was found to be increased, resulting in a low neutrophil-to-lymphocyte ratio.

CONCLUSION

Our proposed super HPD was likely to represent a true HPD, with a frequency of 7.7%.

A case report on severe nivolumab-induced adverse events similar to primary sclerosing cholangitis refractory to immunosuppressive therapy

INTRODUCTION

Immune checkpoint inhibitors (ICIs), particularly anti-PD-1 antibody, have dramatically changed cancer treatment; however, fatal immune-related adverse events (irAEs) can develop. Here, we describe a severe case of sclerosing cholangitis-like irAE. We report the use of 3 immunosuppressive agents that resulted in the death of the patient due to treatment inefficacy. According to a postmarketing study of nivolumab, the frequency of ICI-related sclerosing cholangitis is 0.27% and that of ICI-related cholangitis is 0.20%. There have been 4 case reports of sclerosing cholangitis-like irAE, with imaging findings, including typical intrahepatic bile duct beaded constriction in primary sclerosing cholangitis. Treatment starts with prednisolone and is combined with an immunosuppressant in refractory cases. There are no reports of severe cases that ultimately led to death.

PATIENTS CONCERNS

The patient is a 64-year-old male with Stage IV squamous cell lung carcinoma; he was hospitalized with abdominal pain and elevation of aspartate transaminase and alanine transaminase, approximately 4 months after ICI administration was suspended. This occurred because the patient treated with nivolumab as the second-line chemotherapy and developed type 1 diabetes mellitus after 11 courses.

DIAGNOSIS

A grade 3 increase in bilirubin was observed and he was diagnosed with sclerosing cholangitis, based on magnetic resonance cholangiopancreatography imaging and pathological findings of the liver and bile duct.

INTERVENTIONS

Prednisolone, mycophenolate mofetil, and tacrolimus combination therapy was administered.

OUTCOMES

The treatment was difficult and failed. He died from liver failure 8 months after diagnosis. In this case, hepatitis and cholangitis, mainly alanine transaminase-dominant liver disorder, developed in the early stages of irAEs. Although he showed some improvement after prednisolone administration, bilirubin levels began rising again, and sclerosing cholangitis did not improve even with the use of 3 immunosuppressive agents recommended by the ESMO Clinical Practice Guidelines for immune-related hepatotoxicity management. Although the antitumor effect showed a complete response, liver failure led to death.

CONCLUSION

This is the first case report on the ineffectiveness of triple immunosuppressant combination therapy recommended by the guidelines for immune-related hepatotoxicity. It is necessary to develop more appropriate treatment for severe sclerosing cholangitis-like irAE based on the robust evidence.

Minimal contribution of the hepatic uptake transporter OATP1B1 to the inter-individual variability in SN-38 pharmacokinetics in cancer patients without severe renal failure

PURPOSE

SN-38, a pharmacologically active metabolite of irinotecan, is taken up into hepatocytes by organic anion transporting polypeptide (OATP) 1B1. The effects of functional OATP1B1 521T>C on the pharmacokinetics of SN-38 remain controversial. Here, we prospectively examined the effects of OATP1B1 function on the area under the plasma total or unbound concentration-time curve (tAUC or uAUC) of SN-38 by assessing OATP1B1 521T>C and the plasma levels of endogenous OATP1B1 substrates, coproporphyrin (CP)-I and III, in cancer patients treated with irinotecan.

METHODS

We enrolled cancer patients who were treated with an irinotecan-containing regimen and did not have severe renal failure. The total and unbound concentrations of SN-38 in the plasma were measured by high-performance liquid chromatography. AUC values were calculated and normalized to the actual irinotecan dose (AUC/dose). The OATP1B1 521T>C was analyzed by direct sequencing. Concentrations of the endogenous substrates in plasma before irinotecan treatment (baseline) were determined by liquid chromatography with tandem mass spectrometry.

RESULTS

Twenty-two patients with a median estimated glomerular filtration rate of 74.8 mL/min (range 32.6-99.6) were examined. Both tAUC/dose and uAUC/dose were associated with the grade of neutropenia; however, they were not associated with OATP1B1 521T>C or baseline CP-I and III levels. It is worth noting that these baseline concentrations were significantly higher in patients with OATP1B1 521C, supporting functional changes in OATP1B1.

CONCLUSION

The contribution of OATP1B1 activity to inter-patient variability in the systemic exposure to SN-38 is likely minimal in patients without severe renal failure.

The Prognostic Impact of Eosinophils and the Eosinophil-to-Lymphocyte Ratio on Survival Outcomes in Stage II Resectable Pancreatic Cancer

OBJECTIVES

The relationship between eosinophils and cancer prognosis is unknown. Therefore, we analyzed the relationship between circulating eosinophils and the survival of stage IIA and IIB pancreatic cancer patients who underwent surgical resection.

METHODS

This study included a retrospective cohort of 67 consecutive patients. Patients were categorized into two different groups based on the optimal cutoff for pretreatment levels of each biomarker, according to the receiver operating characteristic curves.

RESULTS

The Kaplan-Meier method showed that low eosinophil (P = 0.0403), high neutrophil (P = 0.0066), and high monocyte (P = 0.0003) counts were associated with short overall survival (OS). Low lymphocyte-to-monocyte ratio (P = 0.0194) and eosinophil-to-lymphocyte ratio (ELR) (P = 0.0413) were associated with reduced OS. In multivariate analysis, histological differentiation (P = 0.0014), high neutrophils (P = 0.047), high monocytes (P = 0.029), and low eosinophils (P < 0.0001) were correlated with poorer OS. Histological differentiation (P = 0.033), low lymphocyte-to-monocyte ratio (P = 0.029), and low ELR (P = 0.005) were correlated with poor OS and were significant independent prognostic factors of poor outcomes.

CONCLUSIONS

Low eosinophils and low ELR were significant independent prognostic factors of poor outcomes.

High levels of human epididymis protein 4 mRNA and protein expression are associated with chemoresistance and a poor prognosis in pancreatic cancer

Pancreatic cancer is associated with an exceedingly poor prognosis, warranting the development of novel therapeutic strategies and discovery of prognostic predictors. Given that chemoresistance‑related molecules are reportedly associated with the poor prognosis of pancreatic cancer, the present study aimed to identify molecules that could be efficacious therapeutic targets for pancreatic cancer. First, 10 patient‑derived xenografts (PDXs) were established from patients with pancreatic cancer. Subsequently, after treating tumor tissue generated from the PDXs with standard drugs, next‑generation sequencing (NGS) was performed using these tissues. The results of NGS analysis and immunohistochemical analysis on 80 pancreatic cancer tissues revealed that human epididymis protein 4 (HE4) expression in the anticancer drug‑treated PDX group was higher than that in the untreated PDXs. In addition, chemoresistance ability was observed in tumor cell lines overexpressing HE4. Furthermore, Kaplan‑Meier analysis of tumor tissues from 80 patients with pancreatic cancer was performed and it was found that patients with a high HE4 expression level had a poor survival rate compared with those who had a low HE4 expression level. Multivariate analysis also indicated the high expression level of HE4 was an independent poor prognostic biomarker. Thus, it was concluded that high gene and protein expression levels of HE4 mediate chemoresistance and are independent prognostic factors for pancreatic cancer.

Cauda Equina and Filum Terminale Arteriovenous Fistulas: Anatomic and Radiographic Features

Intradural AVF below the conus medullaris may develop either on the filum terminale or the cauda equina (lumbosacral and coccygeal radicular nerves). Although not a few filum terminale AVFs are found in the literature, only 3 detailed cauda equina AVFs have been reported. Here, we analyze the angiographic and MR imaging findings of our cauda equina and filum terminale AVF cases, supplemented with literature research to characterize the radiologic features of the 2 entities. On angiography, filum terminale AVFs were invariably supplied by the extension of the anterior spinal artery accompanied by a closely paralleling filum terminale vein. Cauda equina AVFs were fed by either a radicular or a spinal artery or both arteries, often with a characteristic wavy radicular-perimedullary draining vein. On thin-section axial MR imaging, the filum terminale AVF draining vein joined the spinal cord at the conus medullaris apex, but that of the cauda equina AVF joined above the conus medullaris apex.

A high number of PD-L1+ CD14+ monocytes in peripheral blood is correlated with shorter survival in patients receiving immune checkpoint inhibitors

PURPOSE

Targeting of anti-programmed cell death protein-1 (PD-1) and anti-programmed death-ligand 1 (PD-L1) is a standard therapeutic strategy for various cancers. The aim of the present study was to investigate the prognostic effect of pretreatment PD-L1 expression levels in peripheral blood mononuclear cell (PBMC) subsets for patients with several cancer types receiving anti-PD-1 blockade therapies.

PATIENTS AND METHODS

Thirty-two patients undergoing anti-PD-L1 blockade therapy, including 15 with non-small cell lung cancer, 14 with gastric cancer, 1 with melanoma, 1 with parotid cancer, and 1 with bladder cancer, were recruited for the present study. PD-L1 expression levels in CD3⁺, CD4⁺, CD8⁺, CD45RA⁺ and CCR7⁺ T cells; CD20⁺ B cells; CD14⁺ and CD16⁺ monocytes were measured via flow cytometry before treatment. The percentages of PD-L1⁺ cells in respective PBMC subsets were compared with respect to different clinicopathological conditions and the association with overall survival (OS) was assessed.

RESULTS

The percentages of PD-L1⁺ with CD3⁺, CD4⁺ and CD8⁺ T cells including naïve and memory T cell subsets, or CD20⁺ B cells during pretreatment were not markedly correlated with the OS of patients (p > 0.05); however, the percentage of the PD-L1⁺ CD14⁺ monocyte subset was significantly correlated with OS (p = 0.0426).

CONCLUSION

Increase in pretreatment expression levels of PD-L1 on CD14⁺ monocytes is associated with the OS of patients treated with immune checkpoint inhibitors. Further evaluation of large sample size and each specific cancer type might clarify the predictive role of PBMC in patients.

Variants of carboxylesterase 1 have no impact on capecitabine pharmacokinetics and toxicity in capecitabine plus oxaliplatin treated-colorectal cancer patients

PURPOSE

Capecitabine is a prodrug that undergoes metabolism in three steps to form an active 5-fluorouracil (5-FU). The first step is primarily catalyzed by liver carboxylesterases (CES) 1. Here, we examined the effects of CES1 variants on pharmacokinetics and toxicity of capecitabine.

METHODS

We enrolled postoperative colorectal cancer (CRC) patients administered with adjuvant capecitabine plus oxaliplatin (CapeOX) and metastatic CRC patients receiving CapeOX. The pharmacokinetic analysis of the first capecitabine dose (1000 mg/m²) was done on day 1, and oxaliplatin administration was shifted to day 2. Plasma concentrations of capecitabine, 5'-deoxy-5-fluorocytidine, 5'-deoxy-5-fluorouridine (5'-DFUR), and 5-FU were analyzed by high-performance liquid chromatography. CES1 polymorphisms (rs3217164, rs2244614, rs2244613, rs7187684, and rs11861118) and the functional CES1 genes (1A1, var1A1, 1A2, and pseudo 1A3) in their diplotype configurations were analyzed by direct sequencing.

RESULTS

Thirty-seven patients were enrolled from September 2017 to February 2020. Patients with a higher area under the plasma concentration-time curve to capecitabine dose ratio (AUC/dose) of 5'-DFUR than its mean showed a higher frequency of overall ≥ grade 3 toxicity and lower relative dose intensity (RDI) of capecitabine than those with a lower ratio. Higher CES1 activity expressed as a metabolic ratio (AUC of capecitabine/sum of three AUCs of each metabolite) lower than its mean was associated with higher 5'-DFUR AUC/dose and lower RDI, indicating essential roles of CES1 in capecitabine activation to produce 5'-DFUR. However, the association between CES1 variants and capecitabine pharmacokinetics and toxicity was not significant.

CONCLUSION

CES1 variants are not associated with capecitabine pharmacokinetics and toxicity.

High expression levels of polymeric immunoglobulin receptor are correlated with chemoresistance and poor prognosis in pancreatic cancer

Pancreatic cancer has extremely poor prognosis, warranting the discovery of novel therapeutic and prognostic markers. The expression of polymeric immunoglobulin receptor (pIgR), a key component of the mucosal immune system, is increased in several cancers. However, its clinical relevance in pancreatic cancer remains unclear. In the present study, the prognostic value of pIgR in pancreatic cancer patients after surgical resection was assessed and it was determined that the expression of pIgR was correlated with poor prognosis. Ten pancreatic cancer patient‑derived xenograft (PDX) lines were established, followed by next‑generation sequencing of tumor tissues from these lines after standard chemotherapy. Immunohistochemical analysis of chemoresistance‑related molecules using 77 pancreatic cancer tissues was also performed. The expression of pIgR mRNA in the PDX group treated with anticancer drugs was higher than in the untreated group. High pIgR expression in tissue specimens from 77 pancreatic cancer patients was significantly associated with poor prognosis and was revealed to be an independent prognostic factor, predicting poor outcomes. High pIgR mRNA and protein levels were independent prognostic factors, indicating that pIgR could be a novel predictor for poor prognosis of pancreatic cancer patients.

Indocyanine green fluorescence angiography of the reconstructed gastric tube during esophagectomy: efficacy of the 90-second rule

By examining the reconstructed gastric tube during esophagectomy using indocyanine green fluorescence (ICG) angiography, we have established a '90-second rule' to confirm good blood perfusion at the anastomosis site. We examined the surgical outcome (rate of anastomotic leakage) of 70 consecutive patients who underwent esophagectomy with gastric tube reconstruction using ICG fluorescence angiography. All of the anastomoses were made in the area where less than 90 seconds was needed for enhancement using ICG fluorescence angiography (i.e. within the 90-second rule). In 18 cases for which the time until enhancement of the gastric tube tip exceeded 60 seconds, the anastomosis site was decided by reference to the ICG fluorescence angiogram, and the hypoperfused area was excised, and this significantly shortened the median time until enhancement of the gastric tube tip from 95.5 (60.0-204.0) seconds to 41.0 (9.0-77.0) seconds (P < 0.001). In three cases, the anastomosis was made at the site where more than 60 seconds was needed for ICG enhancement. In one case where ICG enhancement had taken 77 seconds, minor anastomotic leakage occurred. The overall rate of anastomotic leakage in this series was 1.4%. Blood flow in the reconstructed gastric tube is sufficient if the anastomosis is made in the area where ICG fluorescence angiography demonstrates enhancement within 60 seconds. Gastric tube necrosis can be avoided if the area showing an enhancement time exceeding 90 seconds is excised. The 90-second rule is a safe and effective method for deciding the site of anastomosis.

Endocytoscopic observation of various esophageal lesions at ×600: can nuclear abnormality be recognized?

Endocytoscopy (ECS) is a novel endoscopic technique that allows detailed diagnostic examination of the gastrointestinal tract at the cellular level. We previously reported that use of ECS at ×380 magnification (GIF-Y0002) allowed a pathologist to diagnose esophageal squamous cell carcinoma (ESCC) with high sensitivity (94.9%) but considerably low specificity (46.7%) because this low magnification did not reveal information about nuclear abnormality. In the present study, we used the same magnifying endoscope to observe various esophageal lesions, but employed digital 1.6-fold magnification to achieve an effective magnification of ×600, and evaluated whether this improved the diagnostic accuracy in distinguishing neoplastic from non-neoplastic lesions.We examined the morphology of surface cells using vital staining with toluidine blue and compared the histological features of 40 cases, including 19 case of ESCC and 21 non-neoplastic esophageal lesions (18 cases of esophagitis, 1 case of glycogenic acanthosis, 1 case of leiomyoma, and 1 case of normal squamous epithelium). One endoscopist classified the lesions using the type classification, and we consulted one pathologist for judgment of the ECS images as 'neoplastic', 'borderline', or 'non-neoplastic'. At ×600 magnification, the pathologist confirmed that nuclear abnormality became evident, in addition to the information about nuclear density provided by observation at ×380. The overall sensitivity and specificity with which the endoscopist was able to predict neoplastic lesions using the type classification was 100% (19/19) and 90.5% (19/21), respectively, in comparison with values of 94.7% (18/19 cases) and 76.2% (16/21), respectively, for the pathologist using a magnification of ×600. The pathologist diagnosed two non-neoplastic lesions and one case of ESCC showing an apparent increase of nuclear density with weak nuclear abnormality as 'borderline'. Among the 21 non-cancerous lesions, two cases of esophagitis that were misdiagnosed by the endoscopist were also misinterpreted as 'neoplastic' by the pathologist. We have shown, by consultation with a pathologist, that an ECS magnification of ×600 (on a 19-inch monitor) is adequate for recognition of nuclear abnormality. We consider that it is feasible to diagnose esophageal neoplasms on the basis of ECS images, and that biopsy histology can be omitted if a combination of increased nuclear density and nuclear abnormality is observed.

Femtosecond-laser-driven photoelectron-gun for time-resolved cathodoluminescence measurement of GaN

A rear-excitation femtosecond-laser-driven photoelectron gun (PE-gun) is developed for measuring time-resolved cathodoluminescence (TRCL) spectrum of wide bandgap materials and structures such as semiconductors and phosphors. The maximum quantum efficiency of a 20-nm-thick Au photocathode excited using a frequency-tripled Al(2)O(3):Ti laser under a rear-excitation configuration is 3.6×10(-6), which is a reasonable value for a PE-gun. When the distance between the front edge of the PE-gun and the observation point is 10 mm, the narrowest electron-beam (e-beam) diameter is 19 μm, which corresponds to one tenth of the laser-beam diameter and is comparable to the initial e-beam diameter of a typical W hair-pin filament of thermionic electron-gun. From the results of TRCL measurements on the freestanding GaN grown by the ammonothermal method and a GaN homoepitaxial film grown by metalorganic vapor phase epitaxy, overall response time for the present TRCL system is estimated to be 8 ps. The value is the same as that of time-resolved photoluminescence measurement using the same excitation laser pulses, meaning that the time-resolution is simply limited by the streak-camera, not by the PE-gun performance. The result of numerical simulation on the temporal e-beam broadening caused by the space-charge-effect suggests that the present PE-gun can be used as a pulsed e-beam source for spatio-time-resolved cathodoluminescence, when equipped in a scanning electron microscope.

Acute generalized exanthematous pustulosis during the puerperal period: a case report

BACKGROUND

Acute generalized exanthematous pustulosis (AGEP) is an uncommon adverse cutaneous reaction, most commonly associated with drugs.

CASE

A 38-year-old primigravida whose labor had been induced developed erythema over her chest and abdomen. She was transferred to our department after a failed vacuum extraction, and delivered a mature infant by forceps. On day three postpartum she developed a 40.4 degrees C fever. Although ceftriaxone was administered, her fever persisted (>38 degreesC). On day six of the puerperium, diffuse non-follicular pustules appeared over her neck and trunk, and AGEP was suspected. Two days after ceftriaxone was withdrawn, the eruptions started to resolve without any medical intervention.

CONCLUSION

Once the diagnosis of AGEP has been made, the antibiotics being administered must be discontinued. If continued treatment is required, pharmacologically distinct antibiotics must be used instead to aid the rapid self-limitation of the disease.

Curative colectomy via minilaparotomy approach without utilizing specific instruments

BACKGROUND

This study evaluated the need for specific instruments when performing a curative resection of colon cancer via a minilaparotomy approach, which has been reported to be a minimally invasive alternative to a laparoscopic approach.

METHODS

The feasibility, safety, and early oncological outcome were compared among 73 patients (first group), in whom a curative resection of colon cancer was performed via a minilaparotomy (skin incision < or =7 cm) utilizing specific instruments (North-bridge retractor system) between September 2002 and March 2005, and 94 patients (second group), in whom a similar procedure was performed without utilizing specific instruments between April 2005 and October 2007.

RESULTS

The two groups did not differ significantly in terms of age, sex, body mass index, site of tumor, level of lymph node dissection, blood loss, UICC stage, number of harvested lymph nodes, incidence of postoperative complications, length of postoperative hospital days, or overall survival, although the frequency of prior abdominal surgery was higher (38.3 vs. 21.9%; P = 0.03) and the median operating time required for a standard lymph node dissection was shorter (120 vs. 135 min; P = 0.03) in the second group.

CONCLUSION

With improved techniques and experience, specific instruments are not necessary for the performance of a curative colectomy via a minilaparotomy approach.

Intrauterine fetal demise due to streptococcal toxic shock syndrome: a case report

BACKGROUND

Toxic shock syndrome caused by group A streptococci (GAS) is rare around the time of delivery, but it may predispose pregnant women to a life-threatening condition.

CASE

A 32-year-old primigravida at 21 weeks of gestation was taken to our hospital with acute severe abdominal pain following fever. On admission the fetus was found to be dead, and intrauterine fetal demise due to placental abruption was suspected. An emergency cesarean section found no sign of placental abruption. Soon after the surgery, the patient went into shock but was successfully treated with intensive care. Although repeated blood cultures failed to detect microorganisms, the patient was positive for streptococcal pyrogenic toxin A, which is a superantigen of GAS.

CONCLUSION

Once GAS infection is suspected, regardless of negative blood cultures, supportive care in the intensive care unit is mandatory.

Polymorphisms of GSTP1, GSTT1, GSTM1, MTHFR, TS, ERCC1, and ERCC2 in metastatic colorectal cancer treated by first-line mFOLFOX6 chemotherapy

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Background: It was reported that determining functional polymorphisms of genes involved in drug-metabolising pathways and DNA repair may be useful for predicting the response to 5-FU/oxaliplatin chemotherapy in Caucasian patients with metastatic colorectal cancer. This study was performed to examine whether determining these polymorphisms had any clinical value in Asian patients with colorectal cancer receiving 5-FU/oxaliplatin therapy. Methods: Genomic DNA was extracted from peripheral blood lymphocytes (n=25) or colonic mucosa (n=47) in Japanese patients with metastatic colorectal cancer who were receiving first-line therapy with the modified FOLFOX6 regimen followed by FOLFIRI (n=42). Polymorphisms of 5 genes involved in drug metabolism (glutathione S-transferase (GST) P1 (IIe 105 Val), GSTT1 deletion, and GSTM1 deletion, methylenetetrahydrofolate reductase (MTHFR) (Ala 677 Val), and a 6-base pair (bp) deletion in the 3’-untranslated region (UTR) of thymidylate synthase (TS)), and polymorphisms of two DNA repair genes (excision repair cross complementing group 1 (ERCC1): Asp 118 Asn and ERCC2: Lys 751 Gln) were assessed in these patients by PCR-RFLP or the invader technique. Correlations between polymorphisms of these genes and the response to therapy were evaluated. Results: The distribution of the genotypes of GSTP1, GSTT1, TS, ERCC1, and ERCC2 in the present Japanese patients (but not that of GSTM1 or MTHFR), differed significantly from the distribution of these genotypes in a Caucasian population. The response rate and progression-free survival were not correlated with any of the functional polymorphisms investigated. However, patients who had both alleles containing the 6-bp nucleotide fragment in the 3’UTR of TS showed significantly shorter overall survival than those who had at least one allele without the 6-bp nucleotide fragment (p=0.03). Conclusions: These results suggest that 3’UTR polymorphism of TS may be an important predictor of overall survival for Japanese patients with metastatic colorectal cancer receiving first-line 5-FU/oxaliplatin therapy.

No significant financial relationships to disclose.

COX-2 inhibition attenuates cough reflex sensitivity to inhaled capsaicin in patients with asthma

BACKGROUND AND OBJECTIVE

Cyclooxygenase (COX) is an enzyme that converts arachidonic acid to prostanoids. There are two isoforms of COX, namely COX-1 and COX-2. COX-2 is highly inducible by several stimuli and is associated with inflammation. Recent studies have shown that COX-2 is upregulated in the airway epithelium of patients with asthma but little is known about the role it plays in cough, a common symptom of bronchial asthma. This study was designed to investigate the role of COX-2 in cough reflex sensitivity in patients with asthma.

PATIENTS AND METHODS

The effect of etodolac, a potent COX-2 inhibitor, on cough response to inhaled capsaicin was examined in 17 patients with stable asthma in a randomized, placebo-controlled crossover study. Capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting 5 or more coughs, was measured as an index of airway cough reflex sensitivity.

RESULTS

The geometric mean (geometric SEM) cough threshold was significantly increased after a 2-week treatment program with oral etodolac (200 mg twice a day) compared with placebo (36.7 [1.2] vs 21.6 [1.2] gM, P<.02).

CONCLUSIONS

These findings indicate that COX-2 may be a possible modulator augmenting airway cough reflex sensitivity in asthmatic airways.

The localization of phytate in tofu curd formation and effects of phytate on tofu texture

The localization of phytate on tofu making and its effects on tofu texture were investigated. Thirty-eight percent and 3% of phytate in soymilk were bound to soluble protein and particulate protein, respectively, and the others were in free form. In the early stage of curd formation, phytate bound to particulate proteins and then a large part of phytate was taken into the tofu curd. Increase of phytate contents in soymilk resulted in the increase of coagulant requirement to make firm tofu. Optimal coagulant concentration (OCC) for making tofu was influenced by phytate contents. The increase of phytate in tofu caused decrease of hardness at OCC and resulted in the increase of brittleness and viscosity of tofu. We concluded that the phytate content is one important factor that contributes to tofu texture.

Urethral transitional cell carcinoma in a cat

A 15-year-old, male neutered cat was referred for investigation of dysuria. A retrograde urethrography was performed which showed two space-occupying masses within the lumen of the mid-to-proximal urethra. Exploratory coeliotomy revealed two urethral masses. Segmental urethrectomy was performed to resect the mass, and the lower urinary tract was reconstructed by vesico-urethral anastomosis. Histopathology showed the mass to be a transitional cell carcinoma with incomplete surgical margins. Tumour regrowth was suspected when dysuria was found approximately 318 days after surgery. Clinical signs were palliated by radiation using weekly fractions of 6 Gy for three weeks. The cat died of unknown causes 386 days postoperatively.

Pitfalls during the Embolization and Evaluation after the Embolization for the Skull Base Meningiomas

Pitfall during the embolization and evaluation after the embolization for skull base meningiomas supplied by meningeal arteries of internal carotid artery (ICA) are reported. This study includes 15 cases of skull base meningiomas (two males and 13 females) that supplied by meningeal branches of internal carotid artery. The preoperative embolization was performed by these feeders. MRI findings and serum levels of C-reactive protein (CRP) after the embolization were examined. In ten patients among 15 patients the meningeal branches of ICA were dominant feeders. In ten patients out of 15 patients, the embolization from the meningeal branches of ICA was possible. Eight patients out of these ten patients were suffered from high fever and increase of serum level of CRP after the embolization. During the embolization for skull base meningiomas, the existence of collateral pathways between the ICA system and external carotid artery system were identified. The increase of serum levels of CRP might be recognized in the patients that effective embolization were performed.

Enhanced signal transduction by a directly fused protein of interleukin-6 and its receptor

In order to develop a new type of agonist for the interleukin 6 (IL-6) signal, the gene encoding a directly fused protein (DFP) was constructed by joining the N-terminal portion of IL-6 and the C-terminal (soluble) portion of IL-6R (sIL-6R) without using a flexible polypeptide linker. The biological activity if DFP from a recombinant Pichia pastoris was examined by growth stimulation of IL-6-dependent BAF130 cells expressing human gp130, a membrane receptor. The recombinant DFP exhibited a much stronger growth stimulation (10 times) than the independent IL-6 and sIL-6R (IL-6/sIL-6R), mainly because association of the IL-6 and IL-6R could be maintained even at lower concentrations of DFP. Surface plasmon resonance (SPR) analysis showed that DFP bound to the extracellular portion of gp130 in the biphasic mode, and the dissociation constants of DFP for two phases were the same as those of IL-6/sIL-6R. In cells treated with DFP, stimulation of Stat3 phosphorylation was maintained for a longer period (150 min) than in cells treated with IL6/Il-6R, suggesting that the signal mediated by the DFP was more durable than that mediated by IL-6/sIL-6R, although the signal transduction mechanisms are almost the same for both DFP and IL-6/IL-6R. Therefore, the stronger activity of DFP was attributed to the maintained association of its subunits and/or prolonged phosphorylation of Stat3.

Homogenous simultaneous detection of HCV RNA and internal control by two-color fluorescence real-time monitoring of isothermal sequence amplification with INAF probes

We demonstrated the homogenous simultaneous detection of HCV RNA and internal control by two-color fluorescence real-time monitoring of isothermal sequence amplification with INAF probes.

Biological Properties of Allogenic Articular Chondrocytes on the Surface of Bovine Cartilage Explants in vitro

Bovine cartilage explants were co-cultured with or without allogenic chondrocytes for 4 weeks. The attachment of the applied chondrocytes to cartilage after labelling with fluorescence was assessed using a confocal laser microscope. Morphological changes and the production of extracellular matrix (ECM) of co-cultured chondrocytes on intact and damaged surfaces of cartilage were evaluated by histological and immunohistochemical methods. Co-cultured chondrocytes attached to and proliferated on the intact and damaged areas of cartilage, and a new layer was created there. The defects were also filled with ECM produced by the co-cultured chondrocytes. Glycosaminoglycans and collagen type II were detected in the newly formed ECM, and large numbers of rounded chondrocytes were observed at primitive lacunae in this matrix at 4 weeks of culture. The results suggest that chondrocytes have the ability to attach to, to proliferate on and to establish a new matrix on the intact and damaged surfaces of cartilage explants.