c-MET-positive circulating tumor cells and cell-free DNA as independent prognostic factors in hormone receptor-positive/HER2-negative metastatic breast cancer.

BACKGROUND: Endocrine therapy resistance in hormone receptor-positive/HER2-negative (HR+/HER2-) breast cancer (BC) is a significant clinical challenge that poses several unmet needs in the management of the disease. This study aimed to investigate the prognostic value of c-MET-positive circulating tumor cells (cMET+ CTCs), ESR1/PIK3CA mutations, and cell-free DNA (cfDNA) concentrations in patients with hormone receptor-positive (HR+) metastatic breast cancer (mBC). METHODS: Ninety-seven patients with HR+ mBC were prospectively enrolled during standard treatment at Samsung Medical Center. CTCs were isolated from blood using GenoCTC® and EpCAM or c-MET CTC isolation kits. PIK3CA and ESR1 hotspot mutations were analyzed using droplet digital PCR. CfDNA concentrations were calculated using internal control copies from the ESR1 mutation test. Immunocytochemistry was performed to compare c-MET overexpression between primary and metastatic sites. RESULTS: The proportion of c-MET overexpression was significantly higher in metastatic sites than in primary sites (p = 0.00002). Survival analysis showed that c-MET+ CTC, cfDNA concentration, and ESR1 mutations were significantly associated with poor prognosis (p = 0.0026, 0.0021, and 0.0064, respectively) in HR+/HER2- mBC. By contrast, EpCAM-positive CTC (EpCAM+ CTC) and PIK3CA mutations were not associated with progression-free survival (PFS) in HR+/HER2- mBC. Multivariate analyses revealed that c-MET+ CTCs and cfDNA concentration were independent predictors of PFS in HR+/HER2- mBC. CONCLUSIONS: Monitoring c-MET+ CTC, rather than assessing c-MET expression in the primary BC site, could provide valuable information for predicting disease progression, as c-MET expression can change during treatment. The c-MET+ CTC count and cfDNA concentration could provide complementary information on disease progression in HR+ /HER2- mBC, highlighting the importance of integrated liquid biopsy.

Clinicopathologic and Molecular Characteristics of HER2 (ERBB2)-Altered Non-Small Cell Lung Cancer: Implications for Precision Medicine.

The heterogeneous relationship between protein expression, amplification, and mutations in human epidermal growth factor receptor 2 (HER2) in non-small cell lung cancer (NSCLC) and the optimal methods for detecting these alterations remain unclear. We aimed to elucidate the clinicopathological and molecular characteristics of HER2-altered NSCLC and investigate practical approaches for identifying patients who might benefit from HER2-targeted therapies. Using next-generation sequencing data from 1680 individuals, we searched for patients with HER2-altered NSCLCs, including amplifications and mutations. Clinicopathological data and tissue slides were reviewed. Immunohistochemistry (IHC) and silver in situ hybridization were performed according to the American Society of Clinical Oncology/College of American Pathologists guidelines. Our analysis identified 89 (5.3%) patients with HER2-altered NSCLCs, comprising 30 (1.8%) with amplification and 59 (3.6%) mutations, and they were compared with 165 control patients. Of the 59 HER2-mutated cases, 52 harbored tyrosine kinase domain (TKD) mutations, primarily HER2 exon 20 insertions. HER2 TKD alterations were associated with younger age, female sex, nonsmoking status, adenocarcinoma with a micropapillary pattern, lung-to-lung metastasis, and poor overall survival. The 33 patients with TKD mutations and 3 with non-TKD point mutations showed incomplete or complete membranous HER2 immunoreactivity (1+ and 2+, 61.07%). Six patients exhibiting amplifications had an IHC score of ≤2+ despite their high copy numbers and concomitantly displayed other actionable EGFR, KRAS, SMARCA4, and other HER2 mutations. These HER2-altered NSCLCs with molecular coalterations showed heterogeneous patterns through HER2 IHC and silver in situ hybridization. Therefore, next-generation sequencing should be used to identify HER2 mutations in patients with NSCLC who present with concomitant alterations. In addition, the above clinicopathological characteristics and HER2 IHC results can be valuable determinants for identifying patients with HER2-altered NSCLC. These insights hold promise for the development of more effective diagnostic and therapeutic strategies for this complex subset of NSCLC patients.

Distinct Recurrence Pattern and Survival Outcomes of Invasive Mucinous Adenocarcinoma of the Lung: The Potential Role of Local Therapy in Intrapulmonary Spread.

BACKGROUND: Invasive mucinous adenocarcinoma (IMA) is distinct from non-mucinous adenocarcinoma, but studies on recurrent IMA are scarce. Thus, this study aimed to evaluate the recurrence patterns of IMA and the role of pulmonary local therapy (LT) in resectable pulmonary recurrence of IMA. METHODS: The study reviewed 403 patients with surgically resected IMA between 1998 and 2018. The recurrence patterns were categorized as solitary pulmonary recurrence (SPR), multiple pulmonary recurrence (MPR), and extra-pulmonary recurrence (EPR). The clinicopathologic characteristics, overall survival (OS), and post-recurrence survival (PRS) were analyzed according to the recurrence pattern and LT administration. RESULTS: Recurrences were found in 91 (22.6%) patients, including 18 patients with SPR, 37 patients with MPR, and 36 patients with EPR. Compared with the MPR and EPR groups, the SPR group had a longer disease-free interval (32.5 vs. 9.6 vs. 10.1 months, respectively; p < 0.01) and a better OS (5-year OS: 88.5%, 41.5%, and 22.9%, respectively; p < 0.01). In case of resectable pulmonary recurrence, pulmonary LT was administered to 15 patients with SPR and 3 patients with MPR. These patients showed a better 5-year PRS than the other patients with pulmonary recurrence (86.3% vs. 30.4%; p < 0.01). Notably, long-term survival was observed for one patient with MPR undergoing LT and two patients with SPR undergoing a second LT for a second pulmonary recurrence. CONCLUSIONS: In this series, the patients with recurrent IMA showed different prognoses according to the recurrence pattern. The patients with pulmonary recurrence of IMA undergoing LT showed a favorable prognosis, suggesting the potential role of LT for resectable pulmonary recurrence of IMA.

PD-L1 expression in resected lung adenocarcinoma: prevalence and prognostic significance in relation to the IASLC grading system.

AIMS: Programmed death-ligand 1 (PD-L1) expression is a predictive biomarker for adjuvant immunotherapy and has been linked to poor differentiation in lung adenocarcinoma. However, its prevalence and prognostic role in the context of the novel histologic grade has not been evaluated. METHODS: We analysed a cohort of 1233 patients with resected lung adenocarcinoma where PD-L1 immunohistochemistry (22C3 assay) was reflexively tested. Tumour PD-L1 expression was correlated with the new standardized International Association for the Study of Lung Cancer (IASLC) histologic grading system (G1, G2, and G3). Clinicopathologic features including patient outcome were analysed. RESULTS: PD-L1 was positive (≥1%) in 7.0%, 23.5%, and 63.0% of G1, G2, and G3 tumours, respectively. PD-L1 positivity was significantly associated with male sex, smoking, and less sublobar resection among patients with G2 tumours, but this association was less pronounced in those with G3 tumours. PD-L1 was an independent risk factor for recurrence (adjusted hazard ratio [HR] = 3.25, 95% confidence intervals [CI] = 1.93-5.48, P < 0.001) and death (adjusted HR = 2.69, 95% CI = 1.13-6.40, P = 0.026) in the G2 group, but not in the G3 group (adjusted HR for recurrence = 0.94, 95% CI = 0.64-1.40, P = 0.778). CONCLUSION: PD-L1 expression differs substantially across IASLC grades and identifies aggressive tumours within the G2 subgroup. This knowledge may be used for both prognostication and designing future studies on adjuvant immunotherapy.

Pragmatic nationwide master observational trial based on genomic alterations in advanced solid tumors: KOrean Precision Medicine Networking Group Study of MOlecular profiling guided therapy based on genomic alterations in advanced Solid tumors (KOSMOS)-II study protocol KCSG AL-22-09.

BACKGROUND: Next-generation sequencing (NGS) has been introduced to many Korean institutions to support molecular diagnostics in cancer since 2017, when it became eligible for reimbursement by the National Health Insurance Service. However, the uptake of molecularly guided treatment (MGT) based on NGS results has been limited because of stringent regulations regarding prescriptions outside of approved indications, a lack of clinical trial opportunities, and limited access to molecular tumor boards (MTB) at most institutions. The KOSMOS-II study was designed to demonstrate the feasibility and effectiveness of MGT, informed by MTBs, using a nationwide precision medicine platform. METHODS: The KOSMOS-II trial is a large-scale nationwide master observational study. It involves a framework for screening patients with metastatic solid tumors for actionable genetic alterations based on local NGS testing. It recommends MGT through a remote and centralized MTB meeting held biweekly. MGT can include one of the following options: Tier 1, the therapeutic use of investigational drugs targeting genetic alterations such as ALK, EGFR, ERBB2, BRAF, FH, ROS1, and RET, or those with high tumor mutational burden; Tier 2, comprising drugs with approved indications or those permitted for treatment outside of the indications approved by the Health Insurance Review and Assessment Service of Korea; Tier 3, involving clinical trials matching the genetic alterations recommended by the MTB. Given the anticipated proportion of patients receiving MGT in the range of 50% ± 3.25%, this study aims to enroll 1,000 patients. Patients must have progressed to one or more lines of therapy and undergone NGS before enrollment. DISCUSSION: This pragmatic master protocol provides a mass-screening platform for rare genetic alterations and high-quality real-world data. Collateral clinical trials, translational studies, and clinico-genomic databases will contribute to generating evidence for drug repositioning and the development of new biomarkers. TRIAL REGISTRATION: NCT05525858.

Plasmonic-Magnetic Active Nanorheology for Intracellular Viscosity.

We demonstrate active plasmonic systems where plasmonic signals are repeatedly modulated by changing the orientation of nanoprobes under an external magnetic field, which is a prerequisite for in situ active nanorheology in intracellular viscosity measurements. Au/Ni/Au nanorods act as "nanotransmitters", which transmit the mechanical motion of nanorods to an electromagnetic radiation signal as a periodic sine function. This fluctuating optical response is transduced to frequency peaks via Fourier transform surface plasmon resonance (FTSPR). As a driving frequency of the external magnetic field applied to the Au/Ni/Au nanorods increases and reaches above a critical threshold, there is a transition from the synchronous motion of nanorods to asynchronous responses, leading to the disappearance of the FTSPR peak, which allows us to measure the local viscosity of the complex fluids. Using this ensemble-based method with plasmonic functional nanomaterials, we measure the intracellular viscosity of cancer cells and normal cells in a reliable and reproducible manner.

NTRK Fusion in a Cohort of BRAF p. V600E Wild-Type Papillary Thyroid Carcinomas.

Owing to the availability of a potent tropomyosin receptor kinase (TRK) inhibitor, it is necessary to develop an effective strategy to identify an enriched population of NTRK fusions in papillary thyroid carcinoma (PTC) in routine diagnostic practice. The reported prevalence of NTRK fusion in a large cohort of PTC is ∼3%. We performed an analysis to refine the characteristic histologic features of PTCs harboring NTRK fusions and further validate the diagnostic utility of pan-TRK immunohistochemistry as a screening tool. In this study, 450 PTCs known to harbor no BRAF p. V600E mutations were screened by pan-TRK immunohistochemistry, and the cases with TRK expression were confirmed by RNA-based next-generation sequencing assay. Eleven NTRK fusion cases were detected (2.4%), and all PTCs were classical subtypes. NTRK1 and NTRK3 were involved in the fusion with 9 different partner genes. Most cases showed similar characteristic histologic findings. Nodular permeative border, multinodular growth with a predominantly follicular pattern, extensive lymphatic invasion, and prominent internodular and intratumoral fibrosis were the characteristic histologic features of NTRK-rearranged PTCs. The ill-defined margins in the ultrasonography findings, which could not be clearly distinguished from the adjacent nontumorous thyroid tissue, were nodular permeative margins in histologic findings. Therefore, preoperative ultrasonographic findings in nodule margins were consistent with the final histologic findings. NTRK1/3 fusion in PTCs showed an overall sensitivity of 100% (95% CI, 71.51%-100%) and specificity of 100% (95% CI, 71.51%-100%) in the 22 cases examined, as confirmed with next-generation sequencing. Our study provides an integrative report of the preoperative ultrasonographic, histologic, immunohistochemical, and molecular features of NTRK-rearranged PTCs. Based on these findings, we propose an algorithmic approach for the stepwise assessment of NTRK fusions in PTCs.

Whole-Section Landscape Analysis of Molecular Subtypes in Curatively Resected Small Cell Lung Cancer: Clinicopathologic Features and Prognostic Significance.

Despite the recognition of various molecular subtypes in small cell lung cancer (SCLC), most information has been derived from tissue microarrays or biopsy samples. Using whole sections of curatively resected SCLCs, we aimed to elucidate the clinicopathologic relevance and prognostic significance of the molecular subtypes. Whole-section immunohistochemistry was conducted for 73 resected SCLC samples using antibodies representative of molecular subtypes: ASCL1 (SCLC-A), NEUROD1 (SCLC-N), POU2F3 (SCLC-P), and YAP1. Furthermore, multiplexed immunofluorescence was performed to evaluate the spatial relationship of YAP1 expression with other markers. The molecular subtype was correlated with clinical and histomorphologic features, and its prognostic role was explored in this cohort and validated in a previously published surgical cohort. Overall, the molecular subtypes were SCLC-A (54.8%), SCLC-N (31.5%), SCLC-P (6.8%), and SCLC-TN (triple negative, 6.8%). We found significant enrichment of SCLC-N (48.0%; P = .004) among combined SCLCs. Although a distinct subtype with high YAP1 expression was not found, YAP1 expression was reciprocal with ASCL1/NEUROD1 at the cellular level within tumors and was increased in areas with non-small cell-like morphology. Furthermore, the YAP1-positive SCLCs showed significantly increased recurrence at mediastinal lymph nodes (P = .047) and are an independent poor prognostic factor after surgery (adjusted hazard ratio, 2.87; 95% CI, 1.20-6.86; P = .017). The poor prognostic impact of YAP1 was also validated in the external surgical cohort. Our whole-section analysis in resected SCLCs reveals the highly heterogeneous nature of the molecular subtype and its clinicopathologic relevance. Although YAP1 is not a subtype delineator, YAP1 relates to the phenotypic plasticity of SCLC and may serve as a poor prognostic factor in resected SCLC.

Different prognostic role of EGFR mutation according to the IASLC histological grade in patients with resected early-stage lung adenocarcinoma.

AIMS: The prognostic role of EGFR mutations remains controversial. We aimed to evaluate the prognostic role of EGFR mutation in consideration of the IASLC histological grade in patients with resected early-stage lung adenocarcinoma. METHODS AND RESULTS: A total of 3297 patients with stages I-IIA resected lung adenocarcinoma who had had EGFR mutation tests between January 2014 and December 2019 at the Samsung Medical Center, Seoul, Korea were included. Recurrence-free survival (RFS) was compared by EGFR mutation status (EGFR-M+ versus EGFR-WT) and IASLC histological grade (G1, G2 and G3). Cox proportional hazards models were used to estimate the adjusted HRs (aHRs) and 95% confidence intervals (CIs). RESULTS: Compared to the EGFR-WT group, the EGFR-M+ group had a significantly lower proportion of G3 tumour (16 versus 33%, P < 0.001). During a median follow-up of 41.4 months, 376 patients experienced recurrence. After adjusting for histological grade, the aHR for recurrence comparing the EGFR-M+ to the EGFR-WT was 1.30 (95% CI = 1.04-1.62, P = 0.022). The EGFR-M+ group had a significantly lower 5-year RFS than the EGFR-WT group among G3 patients (58.4 versus 71.5%, P < 0.001), but not among G1 and G2 patients. CONCLUSIONS: EGFR mutation status was associated with a risk of recurrence after consideration of the IASLC histological grading, especially in G3 tumours. The results of this study would be useful for developing a new staging system and identifying a subset of patients who may benefit from adjuvant targeted therapy.

Clinical Course of Patients With Mediastinal Lymph Node Tuberculosis and Risk Factors for Paradoxical Responses.

BACKGROUND: Paradoxical responses (PR) occur more frequently in lymph node tuberculosis (LNTB) than in pulmonary tuberculosis and present difficulties in differential diagnosis of drug resistance, new infection, poor patient compliance, and adverse drug reactions. Although diagnosis of mediastinal LNTB has become much easier with the development of endosonography, limited information is available. The aim of this study was to investigate the clinical course of mediastinal LNTB and the risk factors associated with PR. METHODS: Patients diagnosed with mediastinal LNTB via endosonography were evaluated retrospectively between October 2009 and December 2019. Multivariable logistic regression was applied to evaluate the risk factors associated with PR. RESULTS: Of 9,052 patients who underwent endosonography during the study period, 158 were diagnosed with mediastinal LNTB. Of these, 55 (35%) and 41 (26%) concurrently had pulmonary tuberculosis and extrapulmonary tuberculosis other than mediastinal LNTB, respectively. Of 125 patients who completed anti-tuberculosis treatment, 21 (17%) developed PR at a median of 4.4 months after initiation of anti-tuberculosis treatment. The median duration of anti-tuberculosis treatment was 6.3 and 10.4 months in patients without and with PR, respectively. Development of PR was independently associated with age < 55 years (adjusted odds ratio [aOR], 5.72; 95% confidence interval [CI], 1.81-18.14; P = 0.003), lymphocyte count < 800/µL (aOR, 8.59; 95% CI, 1.60-46.20; P = 0.012), and short axis diameter of the largest lymph node (LN) ≥ 16 mm (aOR, 5.22; 95% CI, 1.70-16.00; P = 0.004) at the time of diagnosis of mediastinal LNTB. CONCLUSION: As PR occurred in one of six patients with mediastinal LNTB during anti-tuberculosis treatment, physicians should pay attention to patients with risk factors (younger age, lymphocytopenia, and larger LN) at the time of diagnosis.

Matrix metalloproteinase 11 (MMP11) in macrophages promotes the migration of HER2-positive breast cancer cells and monocyte recruitment through CCL2-CCR2 signaling.

Matrix metalloproteinase 11 (MMP11), a member of the MMP family involved in the degradation of the extracellular matrix, has been implicated in cancer progression. Despite the stromal expression of MMP11 in breast cancer, the prognostic significance and role of MMP11 in immune or stromal cells of breast cancer remain unclear. Based on the immunohistochemical analysis of breast cancer tissues from 497 patients, we demonstrated that MMP11 expression in mononuclear inflammatory cells (predominantly macrophages) is an independent negative prognostic factor in breast cancer, whereas MMP11 expression in tumor cells and fibroblasts is not associated with patient survival. Enforced MMP11 expression in breast cancer cells did not promote cell proliferation and migration. However, MMP11-overexpressing macrophages enhanced the migration of HER2-positive (HER2+) breast cancer cells, recruitment of monocytes, and tube formation of endothelial cells. Furthermore, we found that the chemokine CCL2 secreted from MMP11-overexpressing macrophages activated the MAPK pathway via its receptor CCR2 in breast cancer cells, thereby promoting the migration of HER2+ breast cancer cells through MMP9 upregulation. We also found that MMP11 expression in macrophages was stimulated by MMP11-overepressing HER2+ breast cancer cells. Collectively, our findings provide evidence that MMP11 in macrophages may play a pro-tumoral role in HER2+ breast cancer through interaction with cancer cells, monocytes, and endothelial cells.

Durvalumab and tremelimumab with definitive chemoradiotherapy for locally advanced esophageal squamous cell carcinoma.

BACKGROUND: The current standard treatment for patients with inoperable, locally advanced esophageal squamous cell carcinoma (ESCC) is definitive concurrent chemoradiotherapy (CCRT). METHODS: Patients with locally advanced ESCC received 2 cycles of 5-fluorouracil, cisplatin, durvalumab, and tremelimumab every 3 weeks with concurrent radiation therapy (60.2 or 64.5 grays). After completing CCRT plus immunotherapy, patients received 2 cycles of consolidative durvalumab and tremelimumab followed by durvalumab monotherapy every 4 weeks for 2 years after enrollment. Their survival outcomes were compared with those from a propensity score-matched historical control group that had received CCRT alone. RESULTS: In total, 40 patients were enrolled and analyzed. The 24-month progression-free survival (PFS) and overall survival rates were 57.5% and 75%, respectively. Compared with the historical control group (n = 75), the study population had significantly longer PFS (hazard ratio [HR], 0.52; 95% confidence interval [CI], 0.28-0.97; P = .040) and overall survival (HR, 0.49; 95% CI, 0.25-0.98; P = .043). In the study population, patients who had PD-L1-positive tumors (n = 28) had significantly longer PFS (HR, 0.20; 95% CI, 0.07-0.54; P < .001) and overall survival (HR, 0.16; 95% CI, 0.05-0.56; P = .001) compared with those who had PD-L1-negative tumors (n = 11). However, there was no difference in survival outcomes according to PD-L1 status in the historical control group, indicating a strong interaction between PD-L1-positive status and survival outcomes in the treatment groups (PFS, P for interaction = .003; overall survival, P for interaction = .002). CONCLUSIONS: Durvalumab and tremelimumab with definitive CCRT had promising efficacy in patients with locally advanced ESCC. In addition, PD-L1 expression had strong predictive value in the study population.

Trimodality therapy for locally advanced esophageal squamous cell carcinoma: the role of volume-based PET/CT in patient management and prognostication.

PURPOSE: To evaluate the role of positron emission tomography/computed tomography (PET/CT) in predicting pathologic complete response (pCR) and identify relevant prognostic factors from clinico-imaging-pathologic features of locally advanced esophageal squamous cell carcinoma (eSCC) patients undergoing trimodality therapy. METHODS: We evaluated 275 patients with eSCCs of T3-T4aN0M0 and T1-T4aN1-N3M0 who received trimodality therapy. We correlated volume-based PET/CT parameters before and after concurrent chemoradiation therapy with pCR after surgery, clinico-imaging-pathologic features, and patient survival. RESULTS: pCR occurred in 75 (27.3%) of 275 patients, of whom 61 (80.9%) showed 5-year survival. Pre-total lesion glycolysis (pre-TLG, OR = 0.318, 95% CI 0.169 to 0.600), post-metabolic tumor volume (post-MTV, OR = 0.572, 95% CI 0.327 to 0.999), and % decrease of average standardized uptake value (% SUVavg decrease, OR = 2.976, 95% CI = 1.608 to 5.507) were significant predictors for pCR. Among them, best predictor for pCR was pre-TLG with best cutoff value of 205.67 and with AUC value of 0.591. Performance status (HR = 5.171, 95% CI 1.737 to 15.397), pathologic tumor size (HR = 1.645, 95% CI 1.351 to 2.002), pathologic N status (N1, HR = 1.572, 95% CI 1.010 to 2.446; N2, HR = 3.088, 95% CI 1.845 to 5.166), and post-metabolic tumor volume (HR = 1.506, 95% CI 1.033 to 2.195) were significant predictors of overall survival. CONCLUSION: Pre-TLG, post-MTV, and % SUVavg decrease are predictive of pCR. Additionally, several clinico-imaging-pathologic factors are significant survival predictors in locally advanced eSCC patients undergoing trimodality therapy.

NTRK oncogenic fusions are exclusively associated with the serrated neoplasia pathway in the colorectum and begin to occur in sessile serrated lesions.

Neurotrophic tropomyosin receptor kinase (NTRK) gene fusions are emerging tissue-agnostic drug targets in malignancies including colorectal carcinomas (CRCs), but their detailed landscape in the context of various colorectal carcinogenesis pathways remains to be investigated. In this study, pan-tropomyosin receptor kinase (TRK) protein expression was assessed by immunohistochemistry (IHC) in retrospectively collected colorectal epithelial tumor tissues, including 441 CRCs [133 microsatellite instability-high (MSI-high) and 308 microsatellite stable (MSS)] and 595 premalignant colorectal lesions (330 serrated lesions and 265 conventional adenomas). TRK-positive cases were then subjected to next-generation sequencing and/or fluorescence in situ hybridization to confirm NTRK rearrangements. TRK IHC positivity was not observed in any of the MSS CRCs, conventional adenomas, traditional serrated adenomas, or hyperplastic polyps, whereas TRK positivity was observed in 11 of 58 (19%) MLH1-methylated MSI-high CRCs, 4 of 23 (17%) sessile serrated lesions with dysplasia (SSLDs), and 5 of 132 (4%) sessile serrated lesions (SSLs). The 11 TRK-positive MSI-high CRCs commonly harbored CpG island methylator phenotype-high (CIMP-high), MLH1 methylation, BRAF/KRAS wild-type, and NTRK1 or NTRK3 fusion (TPM3-NTRK1, TPR-NTRK1, LMNA-NTRK1, SFPQ-NTRK1, ETV6-NTRK3, or EML4-NTRK3). Both NTRK1 or NTRK3 rearrangement and BRAF/KRAS wild-type were detected in all nine TRK-positive SSL(D)s, seven of which demonstrated MSS and/or CIMP-low. TRK expression was selectively observed in distorted serrated crypts within SSLs and was occasionally localized at the base of serrated crypts. NTRK fusions were detected only in SSLs of patients aged ≥50 years, whereas BRAF mutation was found in younger age-onset SSLs. In conclusion, NTRK-rearranged colorectal tumors develop exclusively through the serrated neoplasia pathway and can be initiated from non-dysplastic SSLs without BRAF/KRAS mutations prior to full occurrence of MSI-high/CIMP-high. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

High concordance of actionable genomic alterations identified between circulating tumor DNA-based and tissue-based next-generation sequencing testing in advanced non-small cell lung cancer: The Korean Lung Liquid Versus Invasive Biopsy Program.

BACKGROUND: Because of the growing number of actionable biomarkers in non-small cell lung cancer (NSCLC), sufficient tissue availability for testing is becoming a greater challenge. Liquid biopsy offers a potential solution by complementing standard tissue-based methods. In this study, the authors analyzed the concordance of actionable genomic alterations sequenced from circulating tumor DNA (ctDNA; Guardant360) and tissue (Oncomine Focus Assay). METHODS: From September 2015 to May 2018, 421 paired plasma and tissue samples from patients with advanced NSCLC who had previously undergone tissue testing by standard methods were collected. Both types of samples were available for 287 patients (262 in cohort 1 [treatment-naive] and 25 in cohort 2 [treatment failure]), and only 1 sample type was available for 134 patients (50 in cohort 3 [plasma only] and 84 in cohort 4 [tissue only]). RESULTS: In cohort 1, 198 samples (77.6%) showed concordance between tissue and plasma next-generation sequencing (NGS). Among the discordant cases, plasma testing detected additional genomic alterations in 11 patients (4.2%). In 50 patients without tissue-based NGS results (cohort 3), the ctDNA-based test detected genomic alterations in 20 samples (40.0%). The median allele frequency (AF) of mutations identified with ctDNA-based NGS (0.74%) was lower than that identified with the tissue-based NGS test (13.90%). Clinical responses to matched targeted therapy occurred, regardless of the ctDNA AF. Upfront ctDNA-based testing identified 60.4% of patients with genomic alterations. In addition, ctDNA-based testing uncovered 12.0% more actionable alterations when it was performed after tissue-based NGS testing. CONCLUSIONS: The results indicate that a ctDNA-based test identifies additional patients with actionable genomic alterations and could, therefore, be used to complement traditional tissue-based testing for NSCLC. LAY SUMMARY: Circulating tumor DNA (ctDNA)-based next-generation sequencing (NGS) testing is becoming essential as the number of actionable genomic biomarker increases for the treatment selection of non-small cell lung cancer. This study demonstrates the additive value of ctDNA-based testing in addition to tissue-based NGS and standard of care-based biomarker testing for detecting additional patients with actionable genomic alterations. Clinical responses have also been observed in patients with a low allele frequency detected by ctDNA-based NGS testing.

PDX models of human lung squamous cell carcinoma: consideration of factors in preclinical and co-clinical applications.

BACKGROUND: Treatment of human lung squamous cell carcinoma (LUSC) using current targeted therapies is limited because of their diverse somatic mutations without any specific dominant driver mutations. These mutational diversities preventing the use of common targeted therapies or the combination of available therapeutic modalities would require a preclinical animal model of this tumor to acquire improved clinical responses. Patient-derived xenograft (PDX) models have been recognized as a potentially useful preclinical model for personalized precision medicine. However, whether the use of LUSC PDX models would be appropriate enough for clinical application is still controversial. METHODS: In the process of developing PDX models from Korean patients with LUSC, the authors investigated the factors influencing the successful initial engraftment of tumors in NOD scid gamma mice and the retainability of the pathological and genomic characteristics of the parental patient tumors in PDX tumors. CONCLUSIONS: The authors have developed 62 LUSC PDX models that retained the pathological and genomic features of parental patient tumors, which could be used in preclinical and co-clinical studies. Trial registration Tumor samples were obtained from 139 patients with LUSC between November 2014 and January 2019. All the patients provided signed informed consents. This study was approved by the institutional review board (IRB) of Samsung Medical Center (2018-03-110).

Soft tissue sarcoma: DWI and DCE-MRI parameters correlate with Ki-67 labeling index.

OBJECTIVES: To examine the correlation of diffusion-weighted and dynamic contrast-enhanced magnetic resonance imaging (MRI) parameters with Ki-67 labeling index (LI) in soft tissue sarcoma (STS). METHODS: The institutional review board approved this retrospective study, and the requirement for informed consent was waived. Thirty-six patients with STS who underwent 3.0-T MRI, including diffusion-weighted and dynamic contrast-enhanced MRI, between July 2011 and February 2018, were included in this study. The mean and minimum apparent diffusion coefficients (ADCs) (ADCmean and ADCmin, respectively), volume transfer constant, reflux rate, and volume fraction of the extravascular extracellular matrix of each lesion were independently analyzed by two readers. Their relationship with the Ki-67 LI was examined using Spearman's correlation analyses. Differences between low- and high-proliferation groups based on Ki-67 LI were evaluated statistically. Optimal cut-off points were determined using the area under the curve analysis for significant parameters. Interobserver agreement was assessed with the intraclass correlation coefficient. RESULTS: ADCmean (ρ = - 0.333, p = 0.047) was significantly and inversely correlated with Ki-67 LI. The high-proliferation group showed a significantly lower ADCmean than did the low-proliferation group (median, 1.08 vs. 1.20; p = 0.048). When a cut-off ADCmean value of 1.16 × 10-3 mm2/s was used, the sensitivity, specificity, and area under the curve for differentiating low- and high-proliferation groups were 75.0%, 60.0%, and 0.712, respectively. Interobserver agreements between the two readers were almost perfect for all parameters. CONCLUSIONS: ADCmean was correlated with Ki-67 LI and could help differentiate between STS with low and high proliferation potential. KEY POINTS: • ADC meanwas significantly and inversely correlated with Ki-67 labeling index in soft tissue sarcoma. • In the high-proliferation group, ADC meanvalues were significantly lower than those of the low-proliferation group.

Nomogram for prediction of lymph node metastasis in patients with superficial esophageal squamous cell carcinoma.

BACKGROUND AND AIM: Knowledge of lymph node metastasis (LNM) status is crucial to determine whether patients with superficial esophageal squamous cell carcinoma (ESCC) can be cured with endoscopic resection alone, without the need for additional esophagectomy. The present study aimed to identify predictive factors and develop a prediction model for LNM in patients with superficial ESCC. METHODS: Clinicopathologic data from 501 patients with superficial ESCC treated with radical esophagectomy were reviewed. Stepwise logistic regression analysis determined the predictors of LNM. Using these predictors, a nomogram for predicting the risk of LNM was constructed and internally validated using a bootstrap resampling method. RESULTS: LNM rates of tumors invading the lamina propria, muscularis mucosa, and SM1 layers were 3.7%, 15.5%, and 40.7%, respectively. Deep tumor invasion depth, moderately or poorly differentiated histology, and lymphovascular invasion were independent predictors of LNM. ESCC with muscularis mucosa and SM1 invasion had odds ratios of 3.635 and 11.834, respectively, compared with that for ESCC confined to the lamina propria. Large tumor size (>2.0 cm) and presence of tumor budding showed borderline significance for LNM prediction. These five variables were incorporated into a nomogram. A constructed nomogram showed good calibration and good discrimination with an area under the receiver-operating characteristic curve (area under the curve [AUC]) of 0.812. After bootstrapping, AUC was 0.811. CONCLUSIONS: We developed a nomogram that can facilitate individualized prediction of risk of LNM in patients with superficial ESCC. This model can aid in decision-making for the need for additional esophagectomy after endoscopic resection for superficial ESCC.

High expression of NR1D1 is associated with good prognosis in triple-negative breast cancer patients treated with chemotherapy.

BACKGROUND: Nuclear receptor subfamily 1, group D, member 1 (NR1D1) is a ligand-regulated nuclear receptor and transcriptional factor. Although recent studies have implicated NR1D1 as a regulator of DNA repair and proliferation in breast cancers, its potential as a therapeutic target for breast cancer has not been assessed in terms of clinical outcomes. Thus, this study aims to analyze NR1D1 expression in breast cancer patients and to evaluate its potential prognostic value. METHODS: NR1D1 expression was analyzed by immunohistochemistry using an anti-NR1D1 antibody in 694 breast cancer samples. Survival analyses were performed using the Kaplan-Meier method with the log-rank test to investigate the association of NR1D1 expression with clinical outcome. RESULTS: One hundred thirty-nine of these samples exhibited high NR1D1 expression, mostly in the nucleus of breast cancer cells. NR1D1 expression correlated significantly with histological grade and estrogen receptor status. Overall survival (OS) and disease-free survival (DFS) did not correlate significantly with NR1D1 expression in breast cancer patients regardless of whether they had received chemotherapy. Subgroup analysis performed according to molecular subtype of breast cancer showed a significant influence of high NR1D1 expression on OS (P = 0.002) and DFS (P = 0.007) in patients with triple-negative breast cancer (TNBC) treated with chemotherapy. CONCLUSIONS: High NR1D1 expression level had a favorable impact on OS and DFS in patients with TNBC treated with chemotherapy. NR1D1 should be investigated further as a possible prognostic marker in TNBC patients receiving chemotherapeutic treatment and as a target in the development of chemotherapeutic approaches to treating TNBC.

Co-expression of MDM2 and CDK4 in transformed human mesenchymal stem cells causes high-grade sarcoma with a dedifferentiated liposarcoma-like morphology.

Amplification and overexpression of MDM2 and CDK4 are well-known diagnostic criteria for well-differentiated liposarcoma (WDLPS)/dedifferentiated liposarcoma (DDLPS). Although it was reported that the depletion of MDM2 or CDK4 decreased proliferation in DDLPS cell lines, whether MDM2 and CDK4 induce WDLPS/DDLPS tumorigenesis remains unclear. We examined whether MDM2 and/or CDK4 cause WDLPS/DDLPS, using two types of transformed human bone marrow stem cells (BMSCs), 2H and 5H, with five oncogenic hits (overexpression of hTERT, TP53 degradation, RB inactivation, c-MYC stabilization, and overexpression of HRASv12). In vitro functional experiments revealed that the co-overexpression of MDM2 and CDK4 plays a key role in tumorigenesis by increasing cell growth and migration and inhibiting adipogenic differentiation potency when compared with the sole expression of MDM2 or CDK4. Using mouse xenograft models, we found that the co-overexpression of MDM2 and CDK4 in 5H cells with five additional oncogenic mutations can cause proliferative sarcoma with a DDLPS-like morphology in vivo. Our results suggest that the co-overexpression of MDM2 and CDK4, along with multiple genetic factors, increases the tendency for high-grade sarcoma with a DDLPS-like morphology in transformed human BMSCs by accelerating their growth and migration and blocking their adipogenic potential.