Detection of HPV DNA in Saliva of Patients with HPV-Associated Oropharyngeal Cancer Treated with Radiotherapy.

BACKGROUND: To investigate the technical feasibility of RT-PCR and direct sequencing to quantify HPV DNA in the saliva of patients with Human-Papilloma-Virus related oropharyngeal cancer (HPV-OPC), the level of which is known to predict prognosis after treatment. METHODS: Nine patients with locally advanced HPV-OPC treated with definitive radiotherapy with chemotherapy or cetuximab, or radiotherapy alone between April 2016 and September 2017, were enrolled, two of whom also received induction chemotherapy. Saliva was collected before (baseline), during (mid-RT) and after (post-RT) radiotherapy. HPV-16 DNAs (E6 and E7) in saliva were quantified by RT-PCR and sequencing, the latter using a custom cancer panel. Correlations between HPV DNA levels and clinical outcomes were assessed. RESULTS: Compared to the baseline, the relative cycle threshold (Ct) value of E6 and E7 reduced at the point of mid-RT in the majority of the patients (100% and 75% for E6 and E7, respectively). Similarly, the relative Ct value from the baseline to post-RT reduced in 86% and 100% of the patients for E6 and E7, respectively. During the follow-up period, three patients (33%) experienced disease progression. The relative baseline Ct values of these three patients were in the top 4 of all the patients. The sequences of HPV DNA were detected in five (83%) of six samples of the baseline saliva that underwent DNA sequencing, along with several gene mutations, such as TP53,CDKN2A and PIK3CA. CONCLUSIONS: This study demonstrates that, in addition to detection and quantification of HPV DNA by RT-PCR, detection by sequencing of HPV-DNA using a customized cancer panel is technically possible.

Acute toxicity of hypofractionated radiotherapy for Japanese breast cancer patients after surgery: a single center prospective observational study (HyPORT-BC).

BACKGROUND: This single center prospective observational study was conducted to evaluate the acute toxicity of hypo-fractionated radiotherapy for Japanese breast cancer patients after surgery. METHODS: This study recruited patients who were scheduled for moderately hypo-fractionated radiotherapy including supraclavicular lymph node area (Cohort M) or ultra-hypo-fractionated radiotherapy for the conserved breast (Cohort U) as postoperative treatment for breast cancer. Radiotherapy plans were generated using automated planning system. Irradiation of 42.5 Gy/16 fractions (Cohort M) or 26 Gy/5 fractions (Cohort U) was delivered, and boost irradiation of 10 Gy/5 fractions was added as needed. The primary endpoint was the proportion of grade ≥ 2 acute adverse events within 90 days. The toxicities were evaluated using CTCAE ver 5.0. RESULTS: Between January 2023 and December 2023, 123 patients (81 in Cohort M and 42 in Cohort U) were enrolled. All the included patients were Japanese and completed their planned radiotherapy and were also able to be evaluated for acute adverse events. Grade 1/2/3-5 acute adverse events were observed in 67/12/0 for Cohort M and 31/4/0 for Cohort U. The proportion of grade ≥ 2 acute adverse events within 90 days was 15% (95% confidence interval 8-24%) for Cohort M and 10% (95% confidence interval 3-23%) for Cohort U. CONCLUSIONS: The proportion of acute toxicity of hypo-fractionated radiotherapy for Japanese breast cancer patients after surgery was shown to be acceptable in this study.

Uptake of ultra-hypofractionated radiation therapy following breast-conserving surgery among patients with early-stage breast cancer: a multi-institutional questionnaire survey.

BACKGROUND: In patients with early-stage breast cancer following breast surgery, ultra-hypofractionated (UHF) breast/chest wall radiation therapy (RT) has been shown to be non-inferior to a moderate-hypofractionated (MHF) regimen, with a minimal risk of breast induration, in the FAST-Forward trial, and UHF is now becoming the standard regimen in Europe. Herein, we aimed to investigate Japanese patients' attitudes toward the UHF regimen. METHODS: A questionnaire-based survey was conducted at 13 RT centers in nine prefectures across Japan. All patients underwent breast-conserving surgery, followed by either conventional fractionation (2 Gy/fr) or MHF (2.66 Gy/fr) whole-breast irradiation (WBI) with or without a tumor bed boost. The questionnaire consisted of 13 questions mainly addressing quality-of-life during RT. Key questions included an 11-point scale (0-10) for rating the patients' enthusiasm for the UHF regimen and prioritization of the following treatment-related effects: treatment efficacy, acute/late adverse effects, physical/emotional/financial burden, and breast cosmesis. The patient and treatment characteristics were assessed by a physician. RESULTS: In total, 247 questionnaires were administered between November 2022 and June 2023. The age distribution was as follows: < 50:50 s:60 s: ≥ 70 = 59 (24%):76 (30%):63 (26%):49 (20%). Sixty-nine percent of patients rated their enthusiasm for the UHF regimen at ≥ 6 out of 10 points (45% rated 10/10). Treatment efficacy was the highest priority for most patients (89%), whereas breast cosmesis the lowest priority (53%). CONCLUSIONS: Patients' enthusiasm for UHF-WBI was observed across the cohort. These results could motivate researchers and clinicians to introduce UHF regimens in clinical practice.

Accelerated three-dimensional conformal radiotherapy for early-stage glottic cancer in reducing dose to the internal carotid artery and pharyngeal constrictor muscles.

BACKGROUND: We evaluated clinical and dosimetric outcomes of radiotherapy using two anterior oblique portals (AOP), to reduce the dose to the bilateral internal carotid arteries (CAs) and pharyngeal constrictor muscle (PCM) during early-stage glottic cancer (ESGC) treatment. METHODS: We identified patients with ESGC who underwent definitive radiotherapy between June 2014 and May 2020. RESULTS: Among the 66 patients, 32 (48%) underwent radiotherapy using AOP, and the remaining underwent typical radiotherapy using parallel opposed lateral portals (POLP). The median follow-up duration was 53 months. No significant differences were observed in the 5-year local failure (0%/9.4%), progression-free survival (90.6%/90.8%), and overall survival (90.6%/91.0%) rates between the two groups. The grade ≥2 acute mucositis incidence rate was significantly lower in the AOP group (44%/85%). Radiotherapy using AOP maintained an adequate dose coverage to the target while markedly reducing the CAs and PCM doses. CONCLUSION: Radiotherapy with AOP resulted in favorable clinical and dosimetric outcomes.

Long-term outcomes of patients with oral cavity cancer receiving postoperative radiotherapy after salvage neck dissection for cervical lymph node recurrence.

BACKGROUNDS: We aimed to clarify the outcomes of postoperative radiotherapy (PORT) after salvage neck dissection for cervical lymph node (LN) recurrence in oral cavity cancer. METHODS: We retrospectively evaluated overall survival (OS), recurrence-free survival (RFS), recurrence patterns, and adverse events of 51 patients with high-risk features receiving PORT after salvage neck dissection between 2009 and 2019. RESULTS: After a median follow-up of 7.4 years from PORT initiation, the 7-year OS and RFS rates were 66.3% (95% CI: 54.0-81.3) and 54.6% (95% CI: 42.1-70.9), respectively. Age <70 years and isolated LN recurrence were significantly associated with longer OS and RFS. Among the 22 patients who experienced recurrence, 14 experienced recurrence within the radiation field. PORT-related grade 3 acute mucositis (35%) and late adverse events (osteoradionecrosis [4%] and laryngeal stenosis [2%]) were observed. CONCLUSIONS: PORT after salvage neck dissection for cervical LN recurrence achieved good survival with acceptable toxicity.

Comprehensive single-cell analysis demonstrates radiotherapy-induced infiltration of macrophages expressing immunosuppressive genes into tumor in esophageal squamous cell carcinoma.

Radiotherapy (RT) combined with immunotherapy is promising; however, the immune response signature in the clinical setting after RT remains unclear. Here, by integrative spatial and single-cell analyses using multiplex immunostaining (CODEX), spatial transcriptome (VISIUM), and single-cell RNA sequencing, we substantiated the infiltration of immune cells into tumors with dynamic changes in immunostimulatory and immunosuppressive gene expression after RT. In addition, our comprehensive analysis uncovered time- and cell type-dependent alterations in the gene expression profile after RT. Furthermore, myeloid cells showed prominent up-regulation of immune response-associated genes after RT. Notably, a subset of infiltrating tumor-associated myeloid cells showing PD-L1 positivity exhibited significant up-regulation of immunostimulatory (HMGB1 and ISG15), immunosuppressive (SIRPA and IDO1), and protumor genes (CXCL8, CCL3, IL-6, and IL-1AB), which can be targets of immunotherapy in combination with PD-L1. These datasets will provide information on the RT-induced gene signature to seek an appropriate target for personalized immunotherapy combined with RT and guide the timing of combination therapy.

Subclonal accumulation of immune escape mechanisms in microsatellite instability-high colorectal cancers.

BACKGROUND: Intratumor heterogeneity (ITH) in microsatellite instability-high (MSI-H) colorectal cancer (CRC) has been poorly studied. We aimed to clarify how the ITH of MSI-H CRCs is generated in cancer evolution and how immune selective pressure affects ITH. METHODS: We reanalyzed public whole-exome sequencing data on 246 MSI-H CRCs. In addition, we performed a multi-region analysis from 6 MSI-H CRCs. To verify the process of subclonal immune escape accumulation, a novel computational model of cancer evolution under immune pressure was developed. RESULTS: Our analysis presented the enrichment of functional genomic alterations in antigen-presentation machinery (APM). Associative analysis of neoantigens indicated the generation of immune escape mechanisms via HLA alterations. Multiregion analysis revealed the clonal acquisition of driver mutations and subclonal accumulation of APM defects in MSI-H CRCs. Examination of variant allele frequencies demonstrated that subclonal mutations tend to be subjected to selective sweep. Computational simulations of tumour progression with the interaction of immune cells successfully verified the subclonal accumulation of immune escape mutations and suggested the efficacy of early initiation of an immune checkpoint inhibitor (ICI) -based treatment. CONCLUSIONS: Our results demonstrate the heterogeneous acquisition of immune escape mechanisms in MSI-H CRCs by Darwinian selection, providing novel insights into ICI-based treatment strategies.

Transposable elements potentiate radiotherapy-induced cellular immune reactions via RIG-I-mediated virus-sensing pathways.

Radiotherapy (RT) plus immunotherapy is a promising modality; however, the therapeutic effects are insufficient, and the molecular mechanism requires clarification to further develop combination therapies. Here, we found that the RNA virus sensor pathway dominantly regulates the cellular immune response in NSCLC and ESCC cell lines. Notably, transposable elements (TEs), especially long terminal repeats (LTRs), functioned as key ligands for the RNA virus sensor RIG-I, and the mTOR-LTR-RIG-I axis induced the cellular immune response and dendritic cell and macrophage infiltration after irradiation. Moreover, RIG-I-dependent immune activation was observed in ESCC patient tissue. scRNA sequencing and spatial transcriptome analysis revealed that radiotherapy induced the expression of LTRs, and the RNA virus sensor pathway in immune and cancer cells; this pathway was also found to mediate tumour conversion to an immunological hot state. Here, we report the upstream and ligand of the RNA virus sensor pathway functions in irradiated cancer tissues.

Prognostic impact of EGFR/ALK alterations in leptomeningeal metastasis from lung adenocarcinoma treated with whole-brain radiotherapy.

The prognosis and prognostic factors of patients receiving whole-brain radiotherapy (WBRT) for leptomeningeal metastasis (LM) from lung adenocarcinoma have not been established. Particularly, the impact of EGFR mutations and ALK rearrangements on survival remains unclear. This retrospective study evaluated the prognosis and prognostic factors of patients receiving WBRT for LM. We evaluated overall survival (OS) from WBRT initiation and clinical variables in 80 consecutive patients receiving WBRT for LM from lung adenocarcinoma at our institution between June 2013 and June 2021. After a median follow-up of 5.2 (range 0.5-56.5) months, the median OS was 6.2 months (95% CI 4.4-12.4). Of the 80 patients, 51 were classified as EGFR/ALK mutant (EGFR: 44; ALK: 6; both: 1) and 29 as wild-type. The median OS was 10.4 (95% CI 5.9-20.9) versus 3.8 (95% CI 2.5-7.7) months in the EGFR/ALK-mutant versus wild-type patients (HR = 0.49, P = 0.0063). Multivariate analysis indicated that EGFR/ALK alterations (HR = 0.54, P = 0.021) and Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-1 (HR = 0.25, P < 0.001) were independent factors associated with favorable OS. Among the patients who underwent brain MRI before and after WBRT, intracranial progression-free survival was longer in the 26 EGFR/ALK-mutant than 13 wild-type patients (HR = 0.31, P = 0.0039). Although the prognosis of patients receiving WBRT for LM remains poor, EGFR/ALK alterations and good ECOG PS may positively impact OS in those eligible for WBRT.

Impacts of the STING-IFNAR1-STAT1-IRF1 pathway on the cellular immune reaction induced by fractionated irradiation.

Radiotherapy (RT) combined with immune checkpoint inhibitors has recently produced outstanding results and is expected to be adaptable for various cancers. However, the precise molecular mechanism by which immune reactions are induced by fractionated RT is still controversial. We aimed to investigate the mechanism of the immune response regarding multifractionated, long-term radiation, which is most often combined with immunotherapy. Two human esophageal cancer cell lines, KYSE-450 and OE-21, were irradiated by fractionated irradiation (FIR) daily at a dose of 3 Gy in 5 d/wk for 2 weeks. Western blot analysis and RNA sequencing identified type I interferon (IFN) and the stimulator of IFN genes (STING) pathway as candidates that regulate immune response by FIR. We inhibited STING, IFNAR1, STAT1, and IFN regulatory factor 1 (IRF1) and investigated the effects on the immune response in cancer cells and the invasion of surrounding immune cells. We herein revealed type I IFN-dependent immune reactions and the positive feedback of STING, IRF1, and phosphorylated STAT1 induced by FIR. Knocking out STING, IFNAR1, STAT1, and IRF1 resulted in a poorer immunological response than that in WT cells. The STING-KO KYSE-450 cell line showed significantly less invasion of PBMCs than the WT cell line under FIR. In the analysis of STING-KO cells and migrated PBMCs, we confirmed the occurrence of STING-dependent immune activation under FIR. In conclusion, we identified that the STING-IFNAR1-STAT1-IRF1 axis regulates immune reactions in cancer cells triggered by FIR and that the STING pathway also contributes to immune cell invasion of cancer cells.

Comparative analysis of the immune responses in cancer cells irradiated with X-ray, proton and carbon-ion beams.

Radiotherapy (RT) is an effective treatment option for cancer; however, its efficacy remains less than optimal in locally advanced cancer. Immune checkpoint inhibitor-based therapy, including the administration of anti-PD-L1 antibodies, is a promising approach that works synergistically with RT. Proton beam therapy and carbon-ion therapy are common options for patients with cancer. Proton and carbon ions are reported to induce an immune reaction in cancer cells; however, the underlying mechanisms remain unclear. Here, we aimed to compare the immune responses after irradiation (IR) with X-ray, protons, and carbon ions in an oesophageal cancer cell line and the underlying mechanisms. An oesophageal cancer cell line, KYSE450, was irradiated with 1 fraction/15 GyE (Gy equivalent) of X-ray, proton, or carbon-ion beams, and then, the cells were harvested for RNA sequencing and gene enrichment analysis. We also knocked out STING and STAT1 in the quest for mechanistic insights. RNA sequencing data revealed that gene expression signatures and biological processes were different in KYSE450 irradiated with X-ray, proton, and carbon-ion beams 6-24 h after IR. However, after 3 days, a common gene expression signature was detected, associated with biological pathways involved in innate immune responses. Gene knock-out experiments revealed that the STING-STAT1 axis underlies the immune reactions after IR. X-Ray, proton, and carbon-ion IRs induced similar immune responses, regulated by the STING-STAT1 axis.

The Evolving Genomic Landscape of Esophageal Squamous Cell Carcinoma Under Chemoradiotherapy.

Esophageal squamous cell carcinoma (ESCC) often recurs after chemoradiotherapy, and the prognosis of ESCC after chemoradiotherapy has not improved over the past few decades. The mutation process in chemoradiotherapy-resistant clones and the functional relevance of genetic alterations remain unclear. To address these problems, we performed whole-exome sequencing of 52 tumor samples from 33 patients with ESCC who received radiotherapy combined with 5-fluorouracil/platinum. In multiregion analyses of pretreatment and locally recurrent lesions from five cases, most driver gene-altered clones remained under chemoradiotherapy selection pressure, while few driver gene alterations were acquired at recurrence. The mutation signatures of recurrent ESCC, including increased deletion frequency and platinum dose-dependent base substitution signatures, were substantially different from those of primary ESCC and reflected the iatrogenic impacts of chemoradiotherapy. Single-region analysis of 28 pretreatment tumors indicated that focal copy-number gain at the MYC locus was significantly associated with poor progression-free survival and overall survival after chemoradiotherapy. MYC gain remained throughout the chemoradiotherapy course and potentially contributes to intrinsic resistance to chemoradiotherapy. Consistent with these findings, MYC copy number and mRNA and protein levels in ESCC cell lines correlated positively with resistance to radiotherapy, and MYC knockdown improved sensitivity to radiotherapy. Overall, these data characterize the clonal evolution process induced by chemoradiotherapy and clinically relevant associations for genetic alterations in ESCC. These findings increase our understanding of therapeutic resistance and support the rationale for precision chemoradiotherapy. SIGNIFICANCE: Whole-exome sequencing reveals the genetic evolution of ESCC during chemoradiotherapy, highlighting MYC gain in pretreatment tumors as a potential marker of therapy resistance.

Comparison of a Hybrid IMRT/VMAT technique with non-coplanar VMAT and non-coplanar IMRT for unresectable olfactory neuroblastoma using the RayStation treatment planning system-EUD, NTCP and planning study.

The purpose of this study was to compare hybrid intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (Hybrid IMRT/VMAT), with non-coplanar (nc) IMRT and nc-VMAT treatment plans for unresectable olfactory neuroblastoma (ONB). Hybrid IMRT/VMAT, nc-IMRT and nc-VMAT plans were optimized for 12 patients with modified Kadish C stage ONB. Dose prescription was 65 Gy in 26 fractions. Dose-volume histogram parameters, conformation number (CN), homogeneity index (HI), integral dose and monitor units (MUs) delivered per fraction were assessed. Equivalent uniform dose (EUD) and normal tissue complication probability (NTCP) based on the EUD model (NTCPLogit) and the Lyman-Kutcher-Burman model (NTCPLKB) were also evaluated. We found that the Hybrid IMRT/VMAT plan significantly improved the CN for clinical target volume (CTV) and planning treatment volume (PTV) compared with the nc-VMAT plan. In general, sparing of organs at risk (OARs) is similar with the three techniques, although the Hybrid IMRT/VMAT plan resulted in a significantly reduced Dmax to contralateral (C/L) optic nerve compared with the nc-IMRT plan. The Hybrid IMRT/VMAT plan significantly reduce EUD to the ipsilateral (I/L) and C/L optic nerve in comparison with the nc-IMRT plan and nc-VMAT plan, but the difference in NTCP between the three technique was <1%. We concluded that the Hybrid IMRT/VMAT technique can offer improvement in terms of target conformity and EUD for optic nerves, while achieving equal or better OAR sparing compared with nc-IMRT and nc-VMAT, and can be a viable radiation technique for treating unresectable ONB. However, the clinical benefit of these small differences in dosimetric data, EUD and NTCP of optic nerves may be minimal.

Adverse Events of Concurrent Radiotherapy and ALK Inhibitors for Brain Metastases of ALK-Rearranged Lung Adenocarcinoma.

BACKGROUND: We investigated acute adverse events in patients with brain metastases (BMs) of anaplastic lymphoma kinase-rearranged (ALKr) non-small cell lung cancer (NSCLC) treated with both cranial radiotherapy and tyrosine kinase inhibitors (TKIs) of ALK. PATIENTS AND METHODS: Acute AEs were retrospectively investigated in patients with BMs of ALKr-NSCLC who received both whole-brain radiotherapy (WBRT) and ALK-TKI. For comparison, they were also assessed in patients with epidermal growth factor receptor (EGFR)-mutated NSCLC and wild-type with neither ALK rearrangement nor EGFR mutation treated with WBRT. RESULTS: Two ALKr cases were consequently eligible. Grade 3 otitis media unexpectedly occurred in both cases, while there was one case out of 11 and one case out of 18 of grade 2 otitis media among the EGFR-mutated cases and wild-type cases (p=0.013), respectively. CONCLUSION: Concurrent treatment with WBRT and ALK-TKI may be associated with acute severe ear toxicity in patients with BMs of ALKr-NSCLC.

Serial mutational tracking in surgically resected locally advanced colorectal cancer with neoadjuvant chemotherapy.

BACKGROUND: We aim to investigate the utility of serial gene mutation tracking for locally advanced CRC in those who underwent curative resection following neoadjuvant chemotherapy. METHODS: We prospectively collected 10 locally advanced CRC cases for which curative resection was performed following preoperative neoadjuvant chemotherapy. Tissues from the primary tumour, distant metastatic tumours, and blood plasma were obtained during serial treatment. Comprehensive mutation analysis of 47 cancer-associated genes was performed using a pre-designed gene panel and next-generation sequencing. RESULTS: All cases showed a partial response to neoadjuvant chemotherapy, and pathological R0 resection was accomplished. In primary tumours, non-synonymous mutations were detected at between 1 and 14 sites before chemotherapy and at between 1 and 2 sites after. Founder mutations were precisely detected in blood plasma and metastatic tumours during longitudinal treatment. CONCLUSIONS: Serial mutational analysis indicated that subclonal selection occurs during chemotherapy and that plasma can substitute for tumourous tissue in mutational analysis for drug selection and treatment decisions.

A temporal shift of the evolutionary principle shaping intratumor heterogeneity in colorectal cancer.

Advanced colorectal cancer harbors extensive intratumor heterogeneity shaped by neutral evolution; however, intratumor heterogeneity in colorectal precancerous lesions has been poorly studied. We perform multiregion whole-exome sequencing on ten early colorectal tumors, which contained adenoma and carcinoma in situ. By comparing with sequencing data from advanced colorectal tumors, we show that the early tumors accumulate a higher proportion of subclonal driver mutations than the advanced tumors, which is highlighted by subclonal mutations in KRAS and APC. We also demonstrate that variant allele frequencies of subclonal mutations tend to be higher in early tumors, suggesting that the subclonal mutations are subject to selective sweep in early tumorigenesis while neutral evolution is dominant in advanced ones. This study establishes that the evolutionary principle underlying intratumor heterogeneity shifts from Darwinian to neutral evolution during colorectal tumor progression.

Identification of UHRF2 as a Negative Regulator of Epithelial-Mesenchymal Transition and Its Clinical Significance in Esophageal Squamous Cell Carcinoma.

OBJECTIVE: The involvement of epithelial-mesenchymal transition (EMT) in esophageal squamous cell carcinoma (ESCC) has not been fully elucidated. Here, we aimed to identify EMT-related genes associated with TGF-ß in ESCC and to clarify the role of these genes in the progression of ESCC. METHODS: EMT-related genes associated with TGF-ß expression were identified in patients with ESCC using microarray analysis and public datasets. The effects of ubiquitin-like with PHD and ring finger domains 2 (UHRF2) expression were analyzed in ESCC cell lines. Cell proliferation and invasion were measured using MTT and invasion assays, respectively. UHRF2 mRNA expression was also analyzed in 75 ESCC specimens to determine the clinical significance of UHRF2 in ESCC. RESULTS: Treatment of ESCC cell lines with TGF-ß increased UHRF2 expression. UHRF2 overexpression increased CDH1 (E-cadherin) expression and decreased invasive capacity. The 75 ESCC specimens were divided into the UHRF2 high-expression group (n = 61) and the UHRF2 low-expression group (n = 14). Low UHRF2 expression was significantly correlated with vascular invasion (p = 0.034) and was an independent prognostic factor for poor prognosis (p = 0.005). CONCLUSION: UHRF2 may be a negative regulator of EMT and a novel prognostic biomarker for ESCC.

Additional radiotherapy following endoscopic submucosal dissection for T1a-MM/T1b-SM esophageal squamous cell carcinoma improves locoregional control.

BACKGROUND: Endoscopic submucosal dissection (ESD) can be used as a less invasive treatment option for superficial esophageal cancer involving the muscularis mucosae (T1a-MM) or upper third of the submucosa (T1b-SM1). Additional treatment after ESD is needed to prevent lymph node metastasis. However, the efficacy of radiotherapy following ESD has not been well evaluated. Moreover, the clinical outcomes of patients with large mucosal defects of the esophagus who received radiotherapy after ESD have not been reported. This study aimed to clarify the efficacy of additional radiotherapy following ESD for esophageal squamous cell cancer involving T1a-MM or T1b-SM1. METHODS: We analyzed twenty-seven patients with pathologically confirmed T1a-MM or T1b-SM1 esophageal squamous cell cancer treated by ESD. Thirteen patients received additional radiotherapy (RT group), and the remaining patients did not (non-RT group). Locoregional control (LRC), overall survival, cause-specific survival, and adverse events including treatment-related esophageal strictures were evaluated. RESULTS: The three-year LRC was significantly better for the RT than the non-RT group (100% vs. 57.8%, respectively; p = 0.022). Chemotherapy following ESD did not improve LRC. Multivariate analysis showed that radiotherapy was an independent prognostic factor for better LRC (p = 0.0022). Contrary to the results in LRC, overall and cause-specific survival were not significantly different between the RT and non-RT groups. A subgroup analysis of patients with mucosal defects involving ≥ 3/4 of the esophageal circumference after ESD showed that LRC of the RT group was better than that of the non-RT group (p = 0.049). Treatment-related esophageal strictures were observed in 2 of 6 patients in the RT group with large mucosal defects after ESD. No patients with mucosal defects involving less than 3/4 of the circumference after ESD developed treatment-related strictures. CONCLUSIONS: Radiotherapy after ESD contributed to better LRC in esophageal squamous cell cancer involving pT1a-MM and pT1b-SM1. Esophageal strictures were observed in some patients with large mucosal defects after ESD. Despite leading to better LRC, radiotherapy after ESD should be undertaken after careful consideration for patients with large mucosal defects after ESD.

Circulating exosomal microRNA-203 is associated with metastasis possibly via inducing tumor-associated macrophages in colorectal cancer.

A primary tumor can create a premetastatic niche in distant organs to facilitate the development of metastasis. The mechanism by which tumor cells communicate with host cells to develop premetastatic niches is unclear. We focused on the role of microRNA (miR) signaling in promoting metastasis. Here, we identified miR-203 as a signaling molecule between tumors and monocytes in metastatic colorectal cancer (CRC) patients. Notably, high expression of serum exosomal miR-203, a major form in circulation, was associated with distant metastasis and an independent poor prognostic factor, whereas low expression in tumor tissues was a poor prognostic factor in CRC patients. We also found that exosomes carrying miR-203 from CRC cells were incorporated into monocytes and miR-203 could promote the expression of M2 markers in vitro, suggesting miR-203 promoted the differentiation of monocytes to M2-tumor-associated macrophages (TAMs). In a xenograft mouse model, miR-203-transfected CRC cells developed more liver metastasis compared to control cells. In conclusion, serum exosomal miR-203 expression is a novel biomarker for predicting metastasis, possibly via promoting the differentiation of monocytes to M2-TAMs in CRC. Furthermore, we propose the concept of site-dependent functions for miR-203 in tumor progression.