Prevalence of pathogenic germline variants in the circulating tumor DNA testing.

BACKGROUND: Somatic and germline variants are not distinguishable by circulating tumor DNA (ctDNA) testing without analyzing non-tumor samples. Although confirmatory germline testing is clinically relevant, the criteria for selecting presumed germline variants have not been established in ctDNA testing. In the present study, we aimed to evaluate the prevalence of pathogenic germline variants in clinical ctDNA testing through their variant allele fractions (VAFs). METHODS: A total of consecutive 106 patients with advanced solid tumors who underwent ctDNA testing (Guardant360®) between January 2018 and March 2020 were eligible for this study. To verify the origin of pathogenic variants reported in ctDNA testing, germline sequencing was performed using peripheral blood DNA samples archived in the Clinical Bioresource Center in Kyoto University Hospital (Kyoto, Japan) under clinical research settings. RESULTS: Among 223 pathogenic variants reported in ctDNA testing, the median VAF was 0.9% (0.02-81.8%), and 88 variants with ≥ 1% VAFs were analyzed in germline sequencing. Among 25 variants with ≥ 30% VAFs, seven were found in peripheral blood DNA (BRCA2: n = 6, JAK2: n = 1). In contrast, among the 63 variants with VAFs ranging from 1 to < 30%, only one variant was found in peripheral blood DNA (TP53: n = 1). Eventually, this variant with 15.6% VAF was defined to be an acquired variant, because its allelic distribution did not completely link to those of neighboring germline polymorphisms. CONCLUSION: Our current study demonstrated that VAFs values are helpful for selecting presumed germline variants in clinical ctDNA testing.

How to adjust endoscopic findings to histopathological findings of the stomach: a "histopathology-oriented" correspondence method helps to understand endoscopic findings.

BACKGROUND: Endoscopic findings have now become nearly as detailed as histopathological findings. Thus, one-to-one correspondence and precise feedback of histopathological findings is very desirable but may be very difficult to accomplish. We describe a systematic process called the Kyoto One-to-One Correspondence Method (the KOTO Method) that allows detailed adjustments of endoscopic findings to match histopathological findings. METHODS AND RESULTS: By comparing endoscopic and stereoscopic images of the gastric mucosa, we could obtain one-to-one correspondence between endoscopic images and equivalent histology in 44 of 47 fields. CONCLUSIONS: The histological structure of gastric cancers of the same histological subtype may not be similar. One-to-one correspondence between endoscopic images and gastric mucosal histology (histopathology-oriented correspondence) will improve endoscopic diagnosis and provide more useful information for pathological diagnosis.

Diagnostic ability of magnifying endoscopy with blue laser imaging for early gastric cancer: a prospective study.

BACKGROUND: Blue laser imaging (BLI) is a new image-enhanced endoscopy technique that utilizes a laser light source developed for narrow-band light observation. The aim of this study was to evaluate the usefulness of BLI for the diagnosis of early gastric cancer. METHODS: This single center prospective study analyzed 530 patients. The patients were examined with both conventional endoscopy with white-light imaging (C-WLI) and magnifying endoscopy with BLI (M-BLI) at Kyoto Prefectural University of Medicine between November 2012 and March 2015. The diagnostic criteria for gastric cancer using M-BLI included an irregular microvascular pattern and/or irregular microsurface pattern, with a demarcation line according to the vessel plus surface classification system. Biopsies of the lesions were taken after C-WLI and M-BLI observation. The primary end point of this study was to compare the diagnostic performance between C-WLI and M-BLI. RESULTS: We analyzed 127 detected lesions (32 cancers and 95 non-cancers). The accuracy, sensitivity, and specificity of M-BLI diagnoses were 92.1, 93.8, and 91.6 %, respectively. On the other hand, the accuracy, sensitivity, and specificity of C-WLI diagnoses were 71.7, 46.9, and 80.0 %, respectively. CONCLUSIONS: M-BLI had improved diagnostic performance for early gastric cancer compared with C-WLI. These results suggested that the diagnostic effectiveness of M-BLI is similar to that of magnifying endoscopy with narrow-band imaging (M-NBI).

Incidence of lymphatic involvement in differentiated-type intramucosal gastric cancers as examined by endoscopic resection.

BACKGROUND: Lymphatic involvement may sometimes be detected in differentiated-type intramucosal cancer resected endoscopically during routine examination, but its incidence and clinical significance remain unknown. METHODS: We examined 300 endoscopically resected lesions obtained from 238 patients diagnosed with differentiated-type intramucosal gastric cancer. All sections were subjected to D2-40 monoclonal-based immunohistochemistry. RESULTS: The incidence of lymphatic involvement in differentiated-type intramucosal cancer was 2.0% (6/300). An incidence of 1.8% (5/279) was determined in lesions that were ≤ 3 cm in size and 2.2% (6/276) in those without an ulcer or ulcer scar. Of the six lesions presenting lymphatic involvement, three were determined to be histologically mixed with a predominance of differentiated type, while the other three lesions were pure differentiated type. CONCLUSIONS: We determined that the incidence of lymphatic involvement in differentiated-type intramucosal cancer was 2.0%. To clarify the clinical significance of such lymphatic involvement, it is necessary to detect it with this incidence in mind and to gather and follow up the clinical courses of such cases.

Combination of molecular-targeted drugs with endocrine therapy for hormone-resistant breast cancer.

Overcoming resistance to endocrine therapy is the most intensive research area in estrogen receptor (ER)-positive breast cancer. A strategy to restore endocrine sensitivity using molecular-targeted drugs such as mammalian target of rapamycin inhibitor everolimus along with endocrine therapy has already been used as a treatment option after the progression of previous aromatase inhibitor therapy. Phase II/III clinical trials of several signal pathway inhibitors and cyclin-dependent kinase 4/6 inhibitors are underway. In addition, a randomized phase II trial of the histone deacetylase inhibitor entinostat showed interesting findings. In this review, we summarize the mechanistic principles of combination therapy of molecular-targeted drugs with endocrine therapy by using a hybrid car model.

The inhibitory effect of heat treatment against epithelial-mesenchymal transition (EMT) in human pancreatic adenocarcinoma cell lines.

Epithelial-mesenchymal transition (EMT) plays a crucial role in cancer metastasis. In this study, we evaluated the effect of heat treatment on tumor growth factor-ß1 (TGF-ß1)-induced EMT in pancreatic cancer cells and tried to ascertain the mechanism related to any observed effects. Human pancreatic cancer cell lines (BxPC-3, PANC-1 and MIAPaCa-2) were stimulated by TGF-ß1, and evaluated for morphological changes using immunofluorescence and EMT-related factors (i.e., E-cadherin, Vimentin, Snail or ZEB-1) using RT-PCR. To examine the effect of heat on EMT, the cancer cells were heat-treated at 43°C for 1 h then stimulated with TGF-ß1. We then evaluated whether or not heat treatment changed the expression of EMT-related factors and cell migration and also whether Smad activation was inhibited in TGF-ß signaling. After being treated with TGF-ß1, pancreatic cancer cells resulted in EMT and cell migration was enhanced. Heat treatment inhibited TGF-ß1-induced changes in morphology, inhibited the expression of EMT-related factors, and attenuated TGF-ß1-induced migration in pancreatic cancer cells. Additionally, we observed that heat treatment blocked TGF-ß1-induced phosphorylation of Smad2 in PANC-1 cells. Our results suggest that heat treatment can suppress TGF-ß1-induced EMT and opens the possibility of a new therapeutic use of hyperthermia as a potential treatment for cancer metastasis.

Association between specific human leukocyte antigen alleles and development of thyroid immune-related adverse event.

Aim: Inherent variations in human leukocyte antigen (HLA) alleles have been revealed epidemiologically to influence the development of autoimmune diseases. HLA alleles may thus also be associated with the development of immune-related adverse events (irAEs), such as thyroid irAE. Materials & methods: In this case-control study, 71 cancer patients who received immune checkpoint inhibitors were enrolled and HLA-genotyped and the frequency of HLA alleles was compared. Results: A*26:01, DPA1*01:03 and DPB1*02:01 were significantly more frequent in patients with thyroid irAE than in patients without any irAEs (35.0 vs 3.2% [p = 0.004], 80.0 vs 45.2% [p = 0.020] and 55.0 vs 25.8% [p = 0.044], respectively). Conclusion: A*26:01, DPA1*01:03 and DPB1*02:01 appear to be associated with thyroid irAE.

Everyone has a unique combination of human leukocyte antigens (HLAs) in their body that help the immune system identify threats. HLAs were named from the fact that they were first identified on the surface of human leukocytes. Afterward, HLAs were also found on all human cells. HLAs present antigens to immune cells. These HLAs also influence how the immune system attacks cancer cells. Immune checkpoint inhibitors are drugs that can help the immune system fight cancer, but they sometimes cause severe adverse events. In this study, we investigated whether specific HLA genes are related to the development of an adverse event that affects the thyroid in cancer patients treated with immune checkpoint inhibitors. We found an association between three HLA genes (A*26:01, DPA1*01:03 and DPB1*02:01) and the development of the thyroid adverse event. However, larger studies are needed to confirm and generalize these initial exploratory findings.

A Case of Squamous Cell Carcinoma of Unknown Primary that Responded to the Multi-Tyrosine Kinase Inhibitor Lenvatinib.

Lenvatinib is an oral tyrosine kinase inhibitor of vascular endothelial growth factor receptors 1, 2, and 3, fibroblast growth factor receptors 1 through 4, as well as platelet-derived growth factor receptor α, RET, and KIT. At present, lenvatinib is used in the treatment of thyroid cancer and renal cell carcinoma. We herein report a case of a 67-year-old patient with squamous cell carcinoma of unknown primary who was effectively treated with lenvatinib. The patient was initially diagnosed as having undifferentiated thyroid cancer, and after total thyroidectomy and bilateral lymph node dissection, lenvatinib was administered for the treatment of residual lymph node metastasis. A computed tomography scan after 1 month of lenvatinib administration showed marked regression of the lymph nodes, but interstitial pneumonia was also detected. Because the drug lymphocyte stimulation test for lenvatinib was strongly positive, we concluded that the interstitial pneumonia was induced by lenvatinib. The interstitial pneumonia only improved by the withdrawal of lenvatinib. Finally, his thyroid tumor was diagnosed as a metastasis of squamous cell carcinoma; however, we were unable to identify the primary lesion. This is the first reported case of interstitial pneumonia induced by lenvatinib.

Magnifying Endoscopy with Blue Laser Imaging Improves the Microstructure Visualization in Early Gastric Cancer: Comparison of Magnifying Endoscopy with Narrow-Band Imaging.

BACKGROUNDS: Magnifying endoscopy with blue laser imaging (ME-BLI) for diagnosis of early gastric cancer (EGC) is as effective as magnifying endoscopy with narrow-band imaging (ME-NBI). However, there are different EGCs in microstructure visualization between ME-BLI and ME-NBI. This study aimed to clarify the pathological features of the EGCs, in which microstructure visualization was different between ME-NBI and ME-BLI. METHODS: EGCs were classified into groups A (irregular microsurface pattern (MSP) in ME-BLI and absent MSP in ME-NBI), B (irregular MSP in two modalities), or C (absent MSP in two modalities), according to the vessel plus surface classification. We compared the pathological features of EGCs between the three groups. RESULTS: 17, four, and five lesions could be evaluated in detail in groups A, B and C, respectively. Well-differentiated adenocarcinomas with shallow crypts were more frequent in group A than in group B (58.8 and 0%, resp.). The mean crypt depth of group A was significantly shallower than that of group B (56 ± 20, 265 ± 64 µm, resp., P = 0.0002). CONCLUSIONS: ME-BLI could better visualize the microstructures of the EGCs with shallow crypts compared with ME-NBI. Therefore, ME-BLI could enable a more accurate diagnosis of EGC with shallow crypts.

Blue Laser Imaging-Bright Improves Endoscopic Recognition of Superficial Esophageal Squamous Cell Carcinoma.

Background/Aims. The aim of this study was to evaluate the endoscopic recognition of esophageal squamous cell carcinoma (ESCC) using four different methods (Olympus white light imaging (O-WLI), Fujifilm white light imaging (F-WLI), narrow band imaging (NBI), and blue laser imaging- (BLI-) bright). Methods. We retrospectively analyzed 25 superficial ESCCs that had been examined using the four different methods. Subjective evaluation was provided by three endoscopists as a ranking score (RS) of each image based on the ease of detection of the cancerous area. For the objective evaluation we calculated the color difference scores (CDS) between the cancerous and noncancerous areas with each of the four methods. Results. There was no difference between the mean RS of O-WLI and F-WLI. The mean RS of NBI was significantly higher than that of O-WLI and that of BLI-bright was significantly higher than that of F-WLI. Moreover, the mean RS of BLI-bright was significantly higher than that of NBI. Furthermore, in the objective evaluation, the mean CDS of BLI-bright was significantly higher than that of O-WLI, F-WLI, and NBI. Conclusion. The recognition of superficial ESCC using BLI-bright was more efficacious than the other methods tested both subjectively and objectively.

Linked color imaging improves endoscopic diagnosis of active Helicobacter pylori infection.

BACKGROUND AND STUDY AIMS: Linked color imaging (LCI) is a new image-enhanced endoscopy technique using a laser light source to enhance slight differences in mucosal color. The aim of this study was to compare the usefulness of LCI and conventional white light imaging (WLI) endoscopy for diagnosing Helicobacter pylori (H. pylori). PATIENTS AND METHODS: We retrospectively analyzed images from 60 patients examined with WLI and LCI endoscopy between October 2013 and May 2014. Thirty patients had H. pylori infections, and other thirty patients tested negative for H. pylori after eradication therapy. Four endoscopists evaluated the 2 types of images to determine which was better at facilitating a diagnosis of H. pylori infection. RESULTS: H. pylori infection was identified with LCI by enhancing the red appearance of the fundic gland mucosa. The accuracy, sensitivity, and specificity for diagnosing H. pylori infection using WLI were 74.2 %, 81.7 %, and 66.7 %, respectively, while those for LCI were 85.8 %, 93.3 %, and 78.3 %, respectively. Thus, the accuracy and sensitivity for LCI were significantly higher than those for WLI (P = 0.002 and P = 0.011, respectively). The kappa values for the inter- and intraobserver variability among the 4 endoscopists were higher for LCI than for WLI. CONCLUSIONS: H. pylori infection can be identified by enhancing endoscopic images of the diffuse redness of the fundic gland using LCI. LCI is a novel image-enhanced endoscopy and is more useful for diagnosing H. pylori infection than is WLI.