Mapping the spreading routes of lymphatic metastases in human colorectal cancer

An internally and externally validated nomogram for predicting cancer-specific survival in octogenarians after radical resection for colorectal cancer

AIMS

We aimed to develop an elaborative nomogram that predicts cancer-specific survival (CSS) in American and Chinese octogenarians treated with radical resection for CRC.

METHODS

The patient data of newly diagnosed patients aged 80 years or older who underwent radical resection for CRC from 2010 to 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database and then randomly divided into a training cohort and a validation cohort. The patients collected from our hospital were defined as the external validation cohort. Univariate and multivariate Cox regression was used to select independent predictive factors for the construction of a nomogram to predict 1-, 2- and 3-year CSS.

RESULTS

The multivariate Cox regression model identified age, T stage, N stage, perineural invasion, chemotherapy, tumour deposits, carcinoembryonic antigen level, number of lymph node metastases, and number of solid organ metastases as independent predictors of survival. The C-index of the nomogram for 1-, 2- and 3-year CSS was 0.758, 0.762, and 0.727, respectively, demonstrating significant clinical value and substantial reliability compared to the TNM stage. The calibration curve and area under the curve also indicated considerable predictive accuracy. In addition, decision curve analysis demonstrated desirable net benefits in clinical application.

CONCLUSION

We constructed a nomogram for predicting the CSS of individual octogenarian patients with CRC who underwent radical resection. The nomogram performed better than the TNM staging system in this particular population and could guide clinicians in clinical follow-up and individual therapeutic plan formulation.

Lyophilized lymph nodes for improved delivery of chimeric antigen receptor T cells

Lymph nodes are crucial organs of the adaptive immune system, orchestrating T cell priming, activation and tolerance. T cell activity and function are highly regulated by lymph nodes, which have a unique structure harbouring distinct cells that work together to detect and respond to pathogen-derived antigens. Here we show that implanted patient-derived freeze-dried lymph nodes loaded with chimeric antigen receptor T cells improve delivery to solid tumours and inhibit tumour recurrence after surgery. Chimeric antigen receptor T cells can be effectively loaded into lyophilized lymph nodes, whose unaltered meshwork and cytokine and chemokine contents promote chimeric antigen receptor T cell viability and activation. In mouse models of cell-line-derived human cervical cancer and patient-derived pancreatic cancer, delivery of chimeric antigen receptor T cells targeting mesothelin via the freeze-dried lymph nodes is more effective in preventing tumour recurrence when compared to hydrogels containing T-cell-supporting cytokines. This tissue-mediated cell delivery strategy holds promise for controlled release of various cells and therapeutics with long-term activity and augmented function.

Clinical and Pathologic Predictors of Tumor Deposits in Colorectal Cancer

BACKGROUND

Tumor deposits (TDs) are a special metastatic pattern of colorectal cancer (CRC). This study aims to explore the pathological characteristics of TD and find out the risk factors of TD in CRC.

METHODS

TDs cases of CRC were selected and validated by HE staining. The correlation between TDs and T stages, N stages, and microsatellite instability was calculated by the chi-squared (χ2) test.

RESULTS

A total of 2553 patients with colorectal cancer undergoing intestinal resection were included in this study. Two hundred fifty-nine cases of TDs patients were included. The positive rate of TDs was 1.9% (2/105) in T1, 3.8% (10/266) in T2, 11% (231/2305) in T3, and 22.8% (16/77) in T4. T3 and T4 were more prone to TDs than T1 and T2, but there was no difference between T3 and T4. The positive rate of TDs was 7.2% (107/1491) in N0, 14.3% (152/1062) in N + , and N + was more prone to TDs than N0. The positive rate of TDs was 10.5% (256/2432) in MSS, 2.5% (3/121) in MSI, and MSS was more prone to TDs than MSI. Multivariate analysis showed lymph node invasion, T stage, and MSS were independent risk factors for TDs.

CONCLUSION

Lymph node invasion, T stage, and MSS were independent risk factors for TDs.

Targeting FAPα-positive lymph node metastatic tumor cells suppresses colorectal cancer metastasis

Lymphatic metastasis is the main metastatic route for colorectal cancer, which increases the risk of cancer recurrence and distant metastasis. The properties of the lymph node metastatic colorectal cancer (LNM-CRC) cells are poorly understood, and effective therapies are still lacking. Here, we found that hypoxia-induced fibroblast activation protein alpha (FAPα) expression in LNM-CRC cells. Gain- or loss-function experiments demonstrated that FAPα enhanced tumor cell migration, invasion, epithelial-mesenchymal transition, stemness, and lymphangiogenesis via activation of the STAT3 pathway. In addition, FAPα in tumor cells induced extracellular matrix remodeling and established an immunosuppressive environment via recruiting regulatory T cells, to promote colorectal cancer lymph node metastasis (CRCLNM). Z-GP-DAVLBH, a FAPα-activated prodrug, inhibited CRCLNM by targeting FAPα-positive LNM-CRC cells. Our study highlights the role of FAPα in tumor cells in CRCLNM and provides a potential therapeutic target and promising strategy for CRCLNM.

Tumor-draining lymph nodes: opportunities, challenges, and future directions in colorectal cancer immunotherapy

Tumor-draining lymph nodes (TDLNs) are potential immunotherapy targets that could expand the population of patients with colorectal cancer (CRC) who may benefit from immunotherapy. Currently, pathological detection of tumor cell infiltration limits the acquisition of immune information related to the resected lymph nodes. Understanding the immune function and metastatic risk of specific stages of lymph nodes can facilitate better discussions on the removal or preservation of lymph nodes, as well as the timing of immunotherapy. This review summarized the contribution of TDLNs to CRC responses to immune checkpoint blockade therapy, local immunotherapy, adoptive cell therapy, and cancer vaccines, and discussed the significance of these findings for the development of diagnostics based on TDLNs and the potential implications for guiding immunotherapy after a definitive diagnosis. Molecular pathology and immune spectrum diagnosis of TDLNs will promote significant advances in the selection of immunotherapy options and predicting treatment efficacy.

Integrated multi-omics profiling to dissect the spatiotemporal evolution of metastatic hepatocellular carcinoma

Comprehensive molecular analyses of metastatic hepatocellular carcinoma (HCC) are lacking. Here, we generate multi-omic profiling of 257 primary and 176 metastatic regions from 182 HCC patients. Primary tumors rich in hypoxia signatures facilitated polyclonal dissemination. Genomic divergence between primary and metastatic HCC is high, and early dissemination is prevalent. The remarkable neoantigen intratumor heterogeneity observed in metastases is associated with decreased T cell reactivity, resulting from disruptions to neoantigen presentation. We identify somatic copy number alterations as highly selected events driving metastasis. Subclones without Wnt mutations show a stronger selective advantage for metastasis than those with Wnt mutations and are characterized by a microenvironment rich in activated fibroblasts favoring a pro-metastatic phenotype. Finally, metastases without Wnt mutations exhibit higher enrichment of immunosuppressive B cells that mediate terminal exhaustion of CD8+ T cells via HLA-E:CD94-NKG2A checkpoint axis. Collectively, our results provide a multi-dimensional dissection of the complex evolutionary process of metastasis.

Single-cell deconvolution reveals high lineage- and location-dependent heterogeneity in mesenchymal multivisceral stage 4 colorectal cancer

Metastasized colorectal cancer (CRC) is associated with a poor prognosis and rapid disease progression. Besides hepatic metastasis, peritoneal carcinomatosis is the major cause of death in Union for International Cancer Control (UICC) stage IV CRC patients. Insights into differential site-specific reconstitution of tumor cells and the corresponding tumor microenvironment are still missing. Here, we analyzed the transcriptome of single cells derived from murine multivisceral CRC and delineated the intermetastatic cellular heterogeneity regarding tumor epithelium, stroma, and immune cells. Interestingly, we found an intercellular site-specific network of cancer-associated fibroblasts and tumor epithelium during peritoneal metastasis as well as an autologous feed-forward loop in cancer stem cells. We furthermore deciphered a metastatic dysfunctional adaptive immunity by a loss of B cell-dependent antigen presentation and consecutive effector T cell exhaustion. Furthermore, we demonstrated major similarities of this murine metastatic CRC model with human disease and - based on the results of our analysis - provided an auspicious site-specific immunomodulatory treatment approach for stage IV CRC by intraperitoneal checkpoint inhibition.

A convenient scoring system to distinguish intrahepatic mass-forming cholangiocarcinoma from solitary colorectal liver metastasis based on magnetic resonance imaging features

OBJECTIVES

To develop and validate a diagnostic scoring system to differentiate intrahepatic mass-forming cholangiocarcinoma (IMCC) from solitary colorectal liver metastasis (CRLM).

METHODS

A total of 366 patients (263 in the training cohort, 103 in the validation cohort) who underwent MRI examination with pathologically proven either IMCC or CRLM from two centers were included. Twenty-eight MRI features were collected. Univariate analyses and multivariate logistic regression analyses were performed to identify independent predictors for distinguishing IMCC from solitary CRLM. The independent predictors were weighted over based on regression coefficients to build a scoring system. The overall score distribution was divided into three groups to show the diagnostic probability of CRLM.

RESULTS

Six independent predictors, including hepatic capsular retraction, peripheral hepatic enhancement, vessel penetrating the tumor, upper abdominal lymphadenopathy, peripheral washout at the portal venous phase, and rim enhancement at the portal venous phase were included in the system. All predictors were assigned 1 point. At a cutoff of 3 points, AUCs for this score model were 0.948 and 0.903 with sensitivities of 96.5% and 92.0%, specificities of 84.4% and 71.7%, positive predictive values of 87.7% and 75.4%, negative predictive values of 95.4% and 90.5%, and accuracies of 90.9% and 81.6% for the training and validation cohorts, respectively. An increasing trend was shown in the diagnostic probability of CRLM among the three groups based on the score.

CONCLUSIONS

The established scoring system is reliable and convenient for distinguishing IMCC from solitary CRLM using six MRI features.

CLINICAL RELEVANCE STATEMENT

A reliable and convenient scoring system was developed to differentiate between intrahepatic mass-forming cholangiocarcinoma from solitary colorectal liver metastasis using six MRI features.

KEY POINTS

• Characteristic MRI features were identified to distinguish intrahepatic mass-forming cholangiocarcinoma (IMCC) from solitary colorectal liver metastasis (CRLM). • A model to distinguish IMCC from solitary CRLM was created based on 6 features, including hepatic capsular retraction, upper abdominal lymphadenopathy, peripheral washout at the portal venous phase, rim enhancement at the portal venous phase, peripheral hepatic enhancement, and vessel penetrating the tumor.

Prognosis of carcinoembryonic antigen (CEA) in stage I colorectal adenocarcinoma and development of a prediction model: a retrospective study based on the SEER database

BACKGROUND

To investigate the prognostic significance of preoperative carcinoembryonic antigen (CEA) status in stage I colorectal classical adenocarcinoma (CCA) and mucinous adenocarcinoma (MUC), and to construct a nomogram model of stage I CCA.

METHODS

The SEER database was used to collect 14,226 patients diagnosed with stage I colorectal adenocarcinoma (CA) from 2010 to 2015. The prognostic significance of preoperative CEA status in stage I CA and MUC was examined by propensity-matching score (PSM). We analyzed the factors affecting the prognosis of patients with stage I CCA, and constructed and verified the prognostic model.

RESULTS

After PSM, the cancer-specific survival rate (CCS) of CEA-positive patients in stage T1 and T2 CCA was significantly lower than that of CEA-negative patients in stage T1 and T2 [HR = 0.37 (0.29-0.48), P < 0.001], [HR = 0.52 (0.41-0.65), P < 0.001]. However, there was no significant difference in CSS between CEA-positive and CEA-negative patients in T1 and T2 MUC [HR = 0.58 (0.43-0.79), P = 0.096], [HR = 0.76 (0.36-1.62), P = 0.477]. A nomogram was constructed based on the results of the multivariate COX regression model. Based on the AUC of ROC analysis, calibration plot and decision curve analysis (DCA), we concluded that the risk and prognosis model of CCA showed excellent performance.

CONCLUSION

Elevated CEA is a risk factor for stage I CCA, but not for MUC. And the nomogram is accurate enough to predict the risk and prognostic factors of CCA.

Clinical Effectiveness of Fluorescence Lymph Node Mapping Using ICG for Laparoscopic Right Hemicolectomy: A Prospective Case-Control Study

BACKGROUND

The distinction between D3 lymph nodes and actual lymphatic pathways in primary tumors can be difficult during surgery, making it challenging to confirm the completeness of D3 lymph node dissection. Fluorescence lymph node mapping (FLNM) is a promising method for lymph node visualization.

PURPOSE

This study aimed to assess whether FLNM enhances the effectiveness of D3 lymph node dissection in patients with right-sided colon cancer.

METHODS

Endoscopic submucosal indocyanine green injection were performed on the distal margin of the colon cancer. In an FLNM group, the lymphatic drainage pathway and distribution of D3 lymph nodes were explored. Pathological evaluations were conducted for the fluorescent D3 and non-fluorescent D3 lymph nodes.

RESULTS

The FLNM group showed a significantly higher number of harvested lymph nodes in the D3 area. In stage III patients, the proportion of D3 lymph node metastasis was significantly higher in the FLNM group. The harvested D3 lymph node count showed a proportional correlation with a metastatic lymph node count of up to 15.

CONCLUSION

FLNM could be considered a promising new strategy to potentially increase harvested D3 lymph node counts in colon cancer surgery.

The Negative Prognostic Impact of Lymph Node Skip Metastasis in Stage III Colon Cancer With pN1 Disease: A Single-Center and Retrospective Cohort Study

BACKGROUND

Lymph node skip metastasis is a subgroup of lymph node metastatic patterns with low incidence in node-positive colon cancer. Its clinical significance is still unclear.

OBJECTIVE

This study aimed to investigate the prognostic impact of lymph node skip metastasis in stage III colon cancer.

DESIGN

This is a retrospective observational analysis.

SETTINGS

The study was conducted at the Taipei Veterans General Hospital.

PATIENTS

This study included patients with stage III colon cancer who underwent D3 lymphadenectomy between 2006 and 2015.

MAIN OUTCOME MEASURES

The patients were divided into a lymph node skip metastasis-positive group and a negative group. Recurrence-free survival and overall survival were compared using Kaplan-Meier curves and log-rank test. Cox regression was applied to identify related risk factors influencing survival.

RESULTS

A total of 461 patients were reviewed, and lymph node skip metastasis-positive patients represented 13.2% of our sample. Patients with lymph node skip metastasis tended to present with a higher proportion of right-sided cancer, lower positive lymph nodes, lower lymph node ratio, and higher mean BMI. Liver recurrence was more prevalent in the lymph node skip metastasis group ( p = 0.028) than in the negative group. The presence of lymph node skip metastasis was a negative prognostic factor for 5-year recurrence-free survival (51.4% vs 68.7%; p = 0.002) and 5-year overall survival (66.4% vs 80.4%; p = 0.024) in Kaplan-Meier curves and multivariate Cox regression. Subgroup analysis revealed the survival significance of recurrence-free survival ( p = 0.001) and overall survival ( p = 0.011) in lymph node skip metastasis with pN1 disease.

LIMITATIONS

This study was limited by its retrospective design, single-center nature, and sampling error.

CONCLUSIONS

Lymph node skip metastasis is an independent negative prognostic factor in stage III colon cancer with pN1 disease. More intensive surveillance may be necessary for patients of this subgroup. See Video Abstract at https://links.lww.com/DCR/C60 .

IMPACTO PRONSTICO NEGATIVO DE LAS METSTASIS DISCONTNUAS GANGLIONARES LINFTICAS EN CASOS DE CNCER DE COLON ESTADIO III CON ENFERMEDAD PN ESTUDIO DE COHORTES RETROSPECTIVO MONOCENTRICO

ANTECEDENTES:Las metástasis discontínuas ganglionares linfáticas, son un subgrupo de patrones metastásicos en los ganglios linfáticos con baja incidencia en el cáncer de colon con nódulos positivos. Su significado clínico aún no está claro.OBJETIVO:Estudio que tiene por objetivo el investigar el impacto pronóstico de las metástasis discontínuas de los ganglios linfáticos en el cáncer de colon de estadio III.DISEÑO:Análisis observacional retrospectivo.AJUSTES:El estudio se realizó en el Hospital General de Veteranos de Taipei.PACIENTES:Pacientes con cáncer de colon en estadio III que se sometieron a linfadenectomía D3 entre 2006 y 2015.PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes se dividieron en un grupo positivo de metástasis discontínuas en los ganglios linfáticos y un otro grupo negativo. La sobrevida libre de recidiva y la sobrevida global, fueron comparadas mediante las curvas de Kaplan-Meier y la prueba de rango logarítmico. Se aplicó la regresión de Cox para identificar los factores de riesgo relacionados que influyeron en la sobrevida.RESULTADOS:Se revisaron un total de 461 casos, donde los pacientes positivos con metástasis en los ganglios linfáticos representaron el 13,2% de nuestra muestra. Los pacientes con metástasis discontínuas ganglionares linfáticas tendían a presentar una mayor proporción de cáncer localizado en el lado derecho del colon, presentar un menor numéro de ganglios linfáticos positivos y una proporción menor de ganglios linfáticos con un IMC promedio más alto. Las recidivas hepáticas fueron más prevalentes en el grupo de metástasis discontínuas ganglionares linfáticas ( p = 0,028) que en el grupo negativo. La presencia de metástasis discontínuas ganglionares linfáticas fué un factor de pronóstico negativo en la sobrevida libre de recidiva a 5 años (51,4% frente a 68,7%, p = 0,002) y la sobrevida general a 5 años (66,4% frente a 80,4%, p = 0,024) evaluada por las curvas de Kaplan-Meier y la regresión multivariada de Cox. El análisis de subgrupos reveló la importancia de la sobrevida libre de recidiva ( p = 0,001) y la sobrevida general ( p = 0,011) en los casos con metástasis discontínuas ganglionares linfáticas con enfermedad pN1.LIMITACIONES:Diseño retrospectivo, naturaleza de centro único y error de muestreo.CONCLUSIONES:Las metástasis discontínuas ganglionares linfáticas son un factor pronóstico negativo independiente en los casos de cáncer de colon estadio III con enfermedad pN1. Tal vez sea necesaria una mayor vigilancia de los pacientes en este subgrupo.Consulte Video Resumen en https://links.lww.com/DCR/C60 . (Traducción-Dr. Xavier Delgadillo ).

Associations amongst genes, molecules, cells, and organs in breast cancer metastasis

This paper is a cross fertilization of ideas about the importance of molecular aspects of breast cancer metastasis by basic scientists, a pathologist, and clinical oncologists at the Henry Ford Health symposium. We address four major topics: (i) the complex roles of lymphatic endothelial cells and the molecules that stimulate them to enhance lymph node and systemic metastasis and influence the anti-tumor immunity that might inhibit metastasis; (ii) the interaction of molecules and cells when breast cancer spreads to bone, and how bone metastases may themselves spread to internal viscera; (iii) how molecular expression and morphologic subtypes of breast cancer assist clinicians in determining which patients to treat with more or less aggressive therapies; (iv) how the outcomes of patients with oligometastases in breast cancer are different from those with multiple metastases and how that could justify the aggressive treatment of these patients with the hope of cure.

Genomic and evolutionary characteristics of metastatic gastric cancer by routes

BACKGROUND

In gastric cancer (GC) patients, metastatic progression through the lymphatic, hematogenous, peritoneal, and ovarian routes, is the ultimate cause of death. However, the genomic and evolutionary characteristics of metastatic GC have not been widely evaluated.

METHODS

Whole-exome sequencing data were analyzed for 99 primary and paired metastatic gastric cancers from 15 patients who underwent gastrectomy and metastasectomy.

RESULTS

Hematogenous metastatic tumors were associated with increased chromosomal instability and de novo gain/amplification in cancer driver genes, whereas peritoneal/ovarian metastasis was linked to sustained chromosomal stability and de novo somatic mutations in driver genes. The genomic distance of the hematogenous and peritoneal metastatic tumors was found to be closer to the primary tumors than lymph node (LN) metastasis, while ovarian metastasis was closer to LN and peritoneal metastasis than the primary tumor. Two migration patterns for metastatic GCs were identified; branched and diaspora. Both molecular subtypes of the metastatic tumors, rather than the primary tumor, and their migration patterns were related to patient survival.

CONCLUSIONS

Genomic characteristics of metastatic gastric cancer is distinctive by routes and associated with patients' prognosis along with genomic evolution pattenrs, indicating that both primary and metastatic gastric cancers require genomic evaluation.

Development and validation of a prognostic model incorporating tumor thrombus grading for nonmetastatic clear cell renal cell carcinoma with tumor thrombus: A multicohort study

There is significant variability with respect to the prognosis of nonmetastatic clear cell renal cell carcinoma (ccRCC) patients with venous tumor thrombus (VTT). By applying multiregion whole-exome sequencing on normal-tumor-thrombus-metastasis quadruples from 33 ccRCC patients, we showed that metastases were mainly seeded by VTT (81.8%) rather than primary tumors (PTs). A total of 706 nonmetastatic ccRCC patients with VTT from three independent cohorts were included in this study. C-index analysis revealed that pathological grading of VTT outperformed other indicators in risk assessment (OS: 0.663 versus 0.501-0.610, 0.667 versus 0.544-0.651, and 0.719 versus 0.511-0.700 for Training, China-Validation, and Poland-Validation cohorts, respectively). We constructed a risk predicting model, TT-GPS score, based on four independent variables: VTT height, VTT grading, perinephric fat invasion, and sarcomatoid differentiation in PT. The TT-GPS score displayed better discriminatory ability (OS, c-index: 0.706-0.840, AUC: 0.788-0.874; DFS, c-index: 0.691-0.717, AUC: 0.771-0.789) than previously reported models in risk assessment. In conclusion, we identified for the first-time pathological grading of VTT as an unheeded prognostic factor. By incorporating VTT grading, the TT-GPS score is a promising prognostic tool in predicting the survival of nonmetastatic ccRCC patients with VTT.

Lymphatic Mapping in Colon Cancer Depending on Injection Time and Tracing Agent: A Systematic Review and Meta-Analysis of Prospective Designed Studies

An optimized lymph node yield leads to better survival in colon cancer, but extended lymphadenectomy is not associated with survival benefits. Lymphatic mapping shows several colon cancers feature aberrant drainage pathways inducing local recurrence when not resected. Currently, different protocols exist for lymphatic mapping procedures. This meta-analysis assessed which protocol has the best capacity to detect tumor-draining and possibly metastatic lymph nodes. A systematic review was conducted according to PRISMA guidelines, including prospective trials with in vivo tracer application. The risk of bias was evaluated using the QUADAS-2 tool. Traced lymph nodes, total resected lymph nodes, and aberrant drainage detection rate were analyzed. Fifty-eight studies met the inclusion criteria, of which 42 searched for aberrant drainage. While a preoperative tracer injection significantly increased the traced lymph node rates compared to intraoperative tracing (30.1% (15.4, 47.3) vs. 14.1% (11.9, 16.5), p = 0.03), no effect was shown for the tracer used (p = 0.740) or the application sites comparing submucosal and subserosal injection (22.9% (14.1, 33.1) vs. 14.3% (12.1, 16.8), p = 0.07). Preoperative tracer injection resulted in a significantly higher rate of detected aberrant lymph nodes compared to intraoperative injection (26.3% [95% CI 11.5, 44.0] vs. 2.5% [95% CI 0.8, 4.7], p < 0.001). Analyzing 112 individual patient datasets from eight studies revealed a significant impact on aberrant drainage detection for injection timing, favoring preoperative over intraoperative injection (OR 0.050 [95% CI 0.010-0.176], p < 0.001) while indocyanine green presented itself as the superior tracer (OR 0.127 [95% CI 0.018-0.528], p = 0.012). Optimized lymphatic mapping techniques result in significantly higher detection of aberrant lymphatic drainage patterns and thus enable a personalized approach to reducing local recurrence.

Individualized Clinical Target Volume for Irradiation of the Supraclavicular Region in Breast Cancer Based on Mapping of the Involved Ipsilateral Supraclavicular Lymph Nodes

PURPOSE

To map supraclavicular fossa-involved lymph nodes (SCF-LNs) in patients with nonmetastatic breast cancer, evaluate the coverage of widely adopted atlases, and propose modified borders for individualized regional irradiation.

METHODS AND MATERIALS

M0 patients with biopsy-proven SCF-LNs who were SCF treatment-naïve were included. The SCF was spatially divided into subregions, with each node mapped on the original images. The geographic misses after the borders of multiple atlases were evaluated and factors affecting SCF-LNs' spread pattern were analyzed.

RESULTS

From 1998 to 2022, 209 patients with 1242 SCF-LNs were eligible. Patients had a median of 4 nodes. At least 537 nodes (43.2%) in 147 patients (70.3%) were lateral to the sternocleidomastoid muscle (SCM), and 403 nodes (32.4%) in 127 patients (60.8%) were dorsal to the anterior scalene muscle (ASM). In the 88 patients with ≤3 SCF-LNs, at least 66 nodes (39.1%) in 40 patients (45.5%) were lateral to the SCM, and 34 nodes (20.1%) in 29 patients (33.0%) were dorsal to the ASM. These nodes were not covered by the Radiation Therapy Oncology Group (RTOG) atlas and partly within the Radiotherapy Comparative Effectiveness atlas. One hundred four patients (49.8%) had 432 SCF-LNs (34.8%) beyond the upper border of the European Society for Radiotherapy and Oncology (ESTRO) atlas. In multivariate regression, nodal sizes were associated with wider spread in the primary group. Being triple-negative (TN) subtype was associated with less spread in the recurrent group. Situation-based clinical target volumes (CTVs) were theorized, in which for a sequential spread, the posterior border could be the posterior scalene muscle or even be more constringent; otherwise, it should touch the anterior trapezius surface.

CONCLUSIONS

SCF-LNs tend to spread laterally and dorsally beyond the RTOG borders, even in M0 stages with ≤3 SCF-LNs. The ESTRO upper border does not guarantee coverage with multiple SCF-LNs. Nodal burden and non-TN types are predictive of wider dissemination. A situation-based CTV is possibly feasible. Deciphering the SCF-LN spread route is needed.

The YAP/TEAD4 complex promotes tumor lymphangiogenesis by transcriptionally upregulating CCBE1 in colorectal cancer

The secreted protein Collagen and calcium-binding EGF Domain 1 (CCBE1) is critical for embryonic lymphatic development through its role in the proteolytic activation of mature vascular endothelial growth factor C (VEGFC). We previously reported that CCBE1 is overexpressed in colorectal cancer (CRC) and that its transcription is negatively regulated by the TGFβ-SMAD pathway, but the transcriptional activation mechanism of CCBE1 in CRC remains unknown. Recent studies have revealed the vital role of the hippo effectors YAP/TAZ in lymphatic development; however, the role of YAP/TAZ in tumor lymphangiogenesis has not been clarified. In this study, we found that high nuclear expression of transcription factor TEAD4 is associated with lymph node metastasis and high lymphatic vessel density in CRC patients. YAP/TAZ/TEAD4 complexes transcriptionally upregulated the expression of CCBE1 by directly binding to the enhancer region of CCBE1 in both CRC cells and cancer-associated fibroblasts (CAFs), which resulted in enhanced VEGFC proteolysis and induced tube formation and migration of human lymphatic endothelial cells (HLECs) in vitro and lymphangiogenesis in a CRC cell-derived xenograft (CDX) model in vivo. In addition, the bromodomain and extra-terminal domain (BET) inhibitor JQ1 significantly inhibited the transcription of CCBE1, suppressed VEGFC proteolysis and inhibited tumor lymphangiogenesis in vitro and in vivo. Collectively, our study reveals a new positive transcriptional regulatory mechanism of CCBE1 via YAP/TAZ/TEAD4/BRD4 complexes in CRC, which exposes the protumor lymphangiogenic role of YAP/TAZ and the potential inhibitory effect of BET inhibitors on tumor lymphangiogenesis.

Evolutionary route of nasopharyngeal carcinoma metastasis and its clinical significance

It is critical to understand factors associated with nasopharyngeal carcinoma (NPC) metastasis. To track the evolutionary route of metastasis, here we perform an integrative genomic analysis of 163 matched blood and primary, regional lymph node metastasis and distant metastasis tumour samples, combined with single-cell RNA-seq on 11 samples from two patients. The mutation burden, gene mutation frequency, mutation signature, and copy number frequency are similar between metastatic tumours and primary and regional lymph node tumours. There are two distinct evolutionary routes of metastasis, including metastases evolved from regional lymph nodes (lymphatic route, 61.5%, 8/13) and from primary tumours (hematogenous route, 38.5%, 5/13). The hematogenous route is characterised by higher IFN-γ response gene expression and a higher fraction of exhausted CD8⁺ T cells. Based on a radiomics model, we find that the hematogenous group has significantly better progression-free survival and PD-1 immunotherapy response, while the lymphatic group has a better response to locoregional radiotherapy.

The mesocolic apical fragment in complete mesocolic excision colectomies: Should it be analysed separately? A proof-of-concept study

AIM

The aim of this work is to describe a protocol and assess the feasibility of harvesting and analysing the mesocolic apical fragment (MAF) for the presence of central lymph node (LN) metastasis and extra lymphatic free tumour cells in a random subgroup extracted from a cohort of complete mesocolic excision colectomies with central vascular ligation.

METHOD

Forty-seven patients diagnosed with colorectal cancer were included. A 2/2 cm pyramid of tissue was cut around the central tie and sent for pathological examination. The MAF was sectioned into 16 slices. High-definition images were taken from the slices which were merged into a panoramic three-dimensional image of the MAF. The distribution of LNs in the MAF was quantified. Immunohistochemistry staining for cytokeratin 14 was used to identify isolated tumour cells and micrometastases in the extranodal tissue.

RESULTS

No tumoural cells migrating through the apical zone, outside of the LNs, were identified. Margins of resection, mesocolic tissue and LNs were all negative in the subgroup of ultrastaged MAFs. The number of examined central LNs varied between 0 and 24, with positive MAF LNs being identified only in pN2 stages. The rate of positive apical LNs in our cohort was 4.2% (n = 2).

CONCLUSIONS

The MAF can be easily extracted from standard specimens, allowing for accurate analysis of lymphatic and extra-nodal tumour cells on the central resection margins, in central LNs and in the apical mesocolic tissue. Future research on larger cohorts is required to establish if analysing the MAF has an impact on patient staging, prognosis and management.

Modelling metastatic colonization of cholangiocarcinoma organoids in decellularized lung and lymph nodes

Cholangiocarcinoma (CCA) is a type of liver cancer with an aggressive phenotype and dismal outcome in patients. The metastasis of CCA cancer cells to distant organs, commonly lung and lymph nodes, drastically reduces overall survival. However, mechanistic insight how CCA invades these metastatic sites is still lacking. This is partly because currently available models fail to mimic the complexity of tissue-specific environments for metastatic CCA. To create an in vitro model in which interactions between epithelial tumor cells and their surrounding extracellular matrix (ECM) can be studied in a metastatic setting, we combined patient-derived CCA organoids (CCAOs) (n=3) with decellularized human lung (n=3) and decellularized human lymph node (n=13). Decellularization resulted in removal of cells while preserving ECM structure and retaining important characteristics of the tissue origin. Proteomic analyses showed a tissue-specific ECM protein signature reflecting tissue functioning aspects. The macro and micro-scale mechanical properties, as determined by rheology and micro-indentation, revealed the local heterogeneity of the ECM. When growing CCAOs in decellularized lung and lymph nodes genes related to metastatic processes, including epithelial-to-mesenchymal transition and cancer stem cell plasticity, were significantly influenced by the ECM in an organ-specific manner. Furthermore, CCAOs exhibit significant differences in migration and proliferation dynamics dependent on the original patient tumor and donor of the target organ. In conclusion, CCA metastatic outgrowth is dictated both by the tumor itself as well as by the ECM of the target organ. Convergence of CCAOs with the ECM of its metastatic organs provide a new platform for mechanistic study of cancer metastasis.

Prediction model of colorectal cancer (CRC) lymph node metastasis based on intestinal bacteria

BACKGROUND

Lymph node metastasis is the main metastatic mode of CRC. Lymph node metastasis affects patient prognosis.

OBJECTIVE

To screen differential intestinal bacteria for CRC lymph node metastasis and construct a prediction model.

METHODS

First, fecal samples of 119 CRC patients with lymph node metastasis and 110 CRC patients without lymph node metastasis were included for the detection of intestinal bacterial 16S rRNA. Then, bioinformatics analysis of the sequencing data was performed. Community structure and composition analysis, difference analysis, and intragroup and intergroup correlation analysis were conducted between the two groups. Finally, six machine learning models were used to construct a prediction model for CRC lymph node metastasis.

RESULTS

The community richness and the community diversity at the genus level of the two groups were basically consistent. A total of 12 differential bacteria (Agathobacter, Catenibacterium, norank_f__Oscillospiraceae, Lachnospiraceae_FCS020_group, Lachnospiraceae_UCG-004, etc.) were screened at the genus level. Differential bacteria, such as Agathobacter, Catenibacterium, norank_f__Oscillospiraceae, and Lachnospiraceae_FCS020_group, were more associated with no lymph node metastasis in CRC. In the discovery set, the RF model had the highest prediction accuracy (AUC = 1.00, 98.89% correct, specificity = 55.21%, sensitivity = 55.95%). In the test set, SVM model had the highest prediction accuracy (AUC = 0.73, 72.92% correct, specificity = 69.23%, sensitivity = 88.89%). Lachnospiraceae_FCS020_group was the most important variable in the RF model. Lachnospiraceae_UCG - 004 was the most important variable in the SVM model.

CONCLUSION

CRC lymph node metastasis is closely related to intestinal bacteria. The prediction model based on intestinal bacteria can provide a new evaluation method for CRC lymph node metastasis.

Mechanisms of cancer metastasis

Metastatic cancer is almost always terminal, and more than 90% of cancer deaths result from metastatic disease. Combating cancer metastasis and post-therapeutic recurrence successfully requires understanding each step of metastatic progression. This review describes the current state of knowledge of the etiology and mechanism of cancer progression from primary tumor growth to the formation of new tumors in other parts of the body. Open questions, avenues for future research, and therapeutic approaches with the potential to prevent or inhibit metastasis through personalization to each patient's mutation and/or immune profile are also highlighted.

Nomogram for Predicting Distant Metastasis of Pancreatic Ductal Adenocarcinoma: A SEER-Based Population Study

(1) Background: The aim of this study was to identify risk factors for distant metastasis of pancreatic ductal adenocarcinoma (PDAC) and develop a valid predictive model to guide clinical practice; (2) Methods: We screened 14328 PDAC patients from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015. Lasso regression analysis combined with logistic regression analysis were used to determine the independent risk factors for PDAC with distant metastasis. A nomogram predicting the risk of distant metastasis in PDAC was constructed. A receiver operating characteristic (ROC) curve and consistency-index (C-index) were used to determine the accuracy and discriminate ability of the nomogram. A calibration curve was used to assess the agreement between the predicted probability of the model and the actual probability. Additionally, decision curve analysis (DCA) and clinical influence curve were employed to assess the clinical utility of the nomogram; (3) Results: Multivariate logistic regression analysis revealed that risk factors for distant metastasis of PDAC included age, primary site, histological grade, and lymph node status. A nomogram was successfully constructed, with an area under the curve (AUC) of 0.871 for ROC and a C-index of 0.871 (95% CI: 0.860-0.882). The calibration curve showed that the predicted probability of the model was in high agreement with the actual predicted probability. The DCA and clinical influence curve showed that the model had great potential clinical utility; (4) Conclusions: The risk model established in this study has a good predictive performance and a promising potential application, which can provide personalized clinical decisions for future clinical work.

The functions of N6-methyladenosine (m6A) RNA modifications in colorectal cancer

Colorectal cancers (CRC), which includes colon cancer (CC) and rectal cancer (RC), are some of the most common malignant tumors that are prone to distant metastasis. Its high incidence rate and high mortality rate have attracted much attention. In recent years, epigenetics has attracted increasing attention and has been the focus of many research studies. N6-methyladenosine(m6A) RNA modifications can modify eukaryotic mRNA to impact metabolism. The changes in the m6A regulatory genes are related to the occurrence and development of CRC and play an important role in the pathogenesis of CRC. The effect of m6A RNA modification is regulated by its related regulatory factors ("writer", "eraser", "reader"). In this review, we comprehensively analyzed the effect of m6A methylation on CRC and the relationship between the expression of related regulatory factors and the development and occurrence of CRC. Then, we summarized the roles of m6A and its regulatory factors in CRC and its potential clinical value, which provides a basis for further research on the mechanism of m6A methylation in CRC.

Risk of Local Recurrence After Complete Mesocolic Excision for Right-Sided Colon Cancer: Post-Hoc Sensitivity Analysis of a Population-Based Study

BACKGROUND

A causal treatment effect of complete mesocolic excision for right-sided colon cancer on the risk of recurrence has been shown, but it is still unclear whether this is caused solely by a risk reduction of local recurrence.

OBJECTIVE

The goal of this study was to assess to what extent complete mesocolic excision contributes to the risk of local recurrence.

DESIGN

This study was a posthoc analyses of data from a population-based cohort. Inverse probability of treatment weighting and competing risk analyses were used to estimate the possible causal effects of complete mesocolic excision.

SETTING

Data were collected from the 4 public colorectal cancer centers in the Capital Region of Denmark.

PATIENTS

Patients undergoing elective colon resections for right-sided colon cancer without distant metastases during the period 2010-2013 were included. One center performed complete mesocolic excision and the remaining 3 centers performed conventional resections.

MAIN OUTCOME MEASURES

The primary outcome was the cumulative incidence of solely local recurrence 5.2 years after surgery. Secondary outcomes were solely distant recurrence and both local and distant recurrence diagnosed within 180 days.

RESULTS

A total of 807 patients were included with 186 undergoing complete mesocolic excision and 621 conventional resections. The 5.2-year cumulative incidence of a solely local recurrence was 3.7% (95% CI, 0.5-6.1) after complete mesocolic excision compared with 7.0% (5.0-8.9) in the control group, and the absolute risk reduction of complete mesocolic excision was 3.7% (2.5-7.1; p = 0.035). The absolute risk reduction on local and distant recurrence was 3.4% (1.3-5.6; p = 0.002) and on solely distant recurrence was 3.1% (0.0-6.2; p = 0.052).

LIMITATIONS

The recurrence risk after conventional resection might be underestimated by the use of inappropriate modalities to diagnose local recurrence for some patients and the shorter duration in this group.

CONCLUSION

This study shows a causal treatment effect of complete mesocolic excision on the risk of a solely local recurrence and of distant recurrence with or without local recurrence. See Video Abstract at http://links.lww.com/DCR/B832 .RIESGO DE RECURRENCIA LOCAL DESPUÉS DE LA ESCISIÓN MESOCÓLICA COMPLETA PARA EL CÁNCER DE COLON DEL LADO DERECHO: ANÁLISIS DE SENSIBILIDAD POST-HOC DE UN ESTUDIO POBLACIONALANTECEDENTES:Se ha demostrado un efecto del tratamiento causal de la escisión mesocólica completa para el cáncer de colon del lado derecho sobre el riesgo de recurrencia, pero aún no está claro si esto se debe únicamente a una reducción del riesgo de recurrencia local.OBJETIVO:Evaluar en qué medida la escisión mesocólica completa se atribuye al riesgo de recurrencia local.DISEÑO:Análisis posthoc de datos de una cohorte poblacional. Se utilizaron análisis de probabilidad inversa de ponderación del tratamiento y de riesgo competitivo para estimar los posibles efectos causales de la escisión mesocólica completa.AJUSTE:Datos de los cuatro centros públicos de cáncer colorrectal en la Región Capital de Dinamarca.PACIENTES:Pacientes sometidos a resecciones de colon electivas por cáncer de colon derecho sin metástasis a distancia durante el período 2010-2013. Un centro realizó escisión mesocólica completa, el resto resecciones convencionales.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario fue la incidencia acumulada de la recidiva local únicamente, 5,2 años después de la cirugía. Los resultados secundarios fueron únicamente la recidiva a distancia y ambas,la recidiva local y a distancia diagnosticada dentro de los 180 días.RESULTADOS:Se incluyeron un total de 807 pacientes, 186 sometidos a escisión mesocólica completa y 621 resecciones convencionales. La incidencia acumulada de 5,2 años de una recidiva únicamente local fue del 3,7% (IC del 95%: 0,5 a 6,1) después de la escisión mesocólica completa en comparación con el 7,0% (5,0 a 8,9) en el grupo de control, y la reducción del riesgo absoluto de la escisión mesocólica completa fue del 3,7% (2,5-7,1; p = 0,035). La reducción del riesgo absoluto de recidiva local y distante fue del 3,4% (1,3-5,6; p = 0,0019) y de recidiva únicamente a distancia 3,1% (0,0-6,2; p = 0,052).LIMITANTES:El riesgo de recurrencia después de la resección convencional podría subestimarse por el uso de modalidades inapropiadas para el diagnostico de la recurrencia local en algunos pacientes y la duración más corta en este grupo.CONCLUSIÓN:Este estudio muestra un efecto del tratamiento causal de la escisión mesocólica completa sobre el riesgo de una recidiva únicamente local y de recidiva a distancia con o sin recidiva local. Consulte Video Resumen en http://links.lww.com/DCR/B832 . (Traducción-Dr. Mauricio Santamaria ).

Risk factors of central area lymph nodes metastasis for guiding optimal right colon cancer surgery: A retrospective multicenter study.. [DOI: 10.21203/rs.3.rs-1991182/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background: D3 or CME lymphadenectomy for right colon cancer (RCC) with lymph nodes metastasis (LNM) is strongly recommended but the anatomical landmark remains controversial. Central LNM predicted poor prognosis in RCC and determined the extent of lymphadenectomy. Methods: Data for 1712 RCC patients treated with D3/CME lymphadenectomy were reviewed. These patients had been treated in 9 centers. A total of 1023 RCC patients were enrolled in the derivation cohort while 689 patients were enrolled in the validation cohort. Results: The overall central LNM incidence was 12.58% (215/1712). In the derivation cohort, univariate and multivariate cox regression analyses revealed that preoperative N staging based on CT scan (OR=7.85, 95% CI, 4.53-14.51, p<0.001), tumor differentiation (OR=0.53, 95% CI, 0.33-0.86, p=0.01) and intraoperative view of tumor movability (OR=0.53, 95% CI, 0.33-0.86, p=0.02) were significant independent factors. Areas under receiver-operating characteristic curves (AUC) for assessing central LNM in the derivation and validation cohorts were 0.802 and 0.750, respectively. The risk-scoring system for patients with RCC was also established. A score of 0 points was the optimal cut-off value for central LNM. Compared to patients in the low-risk group, patients in the high-risk group exhibited worse overall survival outcomes (p<0.001).Conclusions: The established model can be used for preoperative assessment of the risk of central LNM in RCC patients, and for determining the landmark for D3/CME lymphadenectomy, therefore might contribute to decreased therapeutic complications and improved clinical outcomes.

Whole-Exome Sequencing Reveals the Genomic Features of the Micropapillary Component in Ground-Glass Opacities

Background: Micropapillary components are observed in a considerable proportion of ground-glass opacities (GGOs) and contribute to the poor prognosis of patients with invasive lung adenocarcinoma (LUAD). However, the underlying mutational processes related to the presence of micropapillary components remain obscure, limiting the development of clinical interventions. Methods: We collected 31 GGOs, which were separated into paired micropapillary and non-micropapillary components using microdissection. Whole-exome sequencing (WES) was performed on the GGO components, and bioinformatics analysis was conducted to reveal the genomic features of the micropapillary component in invasive LUAD. Results: The micropapillary component had more genomic variations, including tumor mutation burden, intratumoral heterogeneity, and copy number variation. We also observed the enrichment of AID/APOBEC mutation signatures and an increased activation of the RTK/Ras, Notch, and Wnt oncogenic pathways within the micropapillary component. A phylogenetic analysis further suggested that ERBB2/3/4, NCOR1/2, TP53, and ZNF469 contributed to the micropapillary component’s progression during the early invasion of LUAD, a finding that was validated in the TCGA cohort. Conclusions: Our results revealed specific mutational characteristics of the micropapillary component of invasive LUAD in an Asian population. These characteristics were associated with the formation of high-grade invasive patterns. These preliminary findings demonstrated the potential of targeting the micropapillary component in patients with early-stage LUAD.

Lymphatic vessels in cancer

The lymphatic system, composed of initial and collecting lymphatic vessels as well as lymph nodes that are present in almost every tissue of the human body, acts as an essential transport system for fluids, biomolecules and cells between peripheral tissues and the central circulation. Consequently, it is required for normal body physiology but is also involved in the pathogenesis of various diseases, most notably cancer. The important role of tumor-associated lymphatic vessels and lymphangiogenesis in the formation of lymph node metastasis has been elucidated during the last two decades, whereas the underlying mechanisms and the relation between lymphatic and peripheral organ dissemination of cancer cells are incompletely understood. Lymphatic vessels are also important for tumor-host communication, relaying molecular information from a primary or metastatic tumor to regional lymph nodes and the circulatory system. Beyond antigen transport, lymphatic endothelial cells, particularly those residing in lymph node sinuses, have recently been recognized as direct regulators of tumor immunity and immunotherapy responsiveness, presenting tumor antigens and expressing several immune-modulatory signals including PD-L1. In this review, we summarize recent discoveries in this rapidly evolving field and highlight strategies and challenges of therapeutic targeting of lymphatic vessels or specific lymphatic functions in cancer patients.

Deciphering clonal dynamics and metastatic routines in a rare patient of synchronous triple-primary tumors and multiple metastases with MPTevol

Multiple primary tumor (MPT) is a special and rare cancer type, defined as more than two primary tumors presenting at the diagnosis in a single patient. The molecular characteristics and tumorigenesis of MPT remain unclear due to insufficient approaches. Here, we present MPTevol, a practical computational framework for comprehensively exploring the MPT from multiregion sequencing (MRS) experiments. To verify the utility of MPTevol, we performed whole-exome MRS for 33 samples of a rare patient with triple-primary tumors and three metastatic sites and systematically investigated clonal dynamics and metastatic routines. MPTevol assists in comparing genomic profiles across samples, detecting clonal evolutionary history and metastatic routines and quantifying the metastatic history. All triple-primary tumors were independent origins and their genomic characteristics were consistent with corresponding sporadic tumors, strongly supporting their independent tumorigenesis. We further showed two independent early monoclonal seeding events for the metastases in the ovary and uterus. We revealed that two ovarian metastases were disseminated from the same subclone of the primary tumor through undergoing whole-genome doubling processes, suggesting metastases-to-metastases seeding occurred when tumors had similar microenvironments. Surprisingly, according to the metastasis timing model of MPTevol, we found that primary tumors of about 0.058–0.124 cm diameter have been disseminating to distant organs, which is much earlier than conventional clinical views. We developed MPT-specialized analysis framework MPTevol and demonstrated its utility in explicitly resolving clonal evolutionary history and metastatic seeding routines with a rare MPT case. MPTevol is implemented in R and is available at https://github.com/qingjian1991/MPTevol under the GPL v3 license.

Intranodal delivery of modified docetaxel: Innovative therapeutic method to inhibit tumor cell growth in lymph nodes

Delivery of chemotherapeutic agents into metastatic lymph nodes (LNs) is challenging as they are unevenly distributed in the body. They are difficult to access via traditional systemic routes of drug administration, which produce significant adverse effects and result in low accumulation of drugs into the cancerous LN. To improve the survival rate of patients with LN metastasis, a lymphatic drug delivery system (LDDS) has been developed to target metastatic LN by delivering chemotherapy agents into sentinel LN (SLN) under ultrasound guidance. The LDDS is an advanced method that can be applied in the early stage of the progression of tumor cells in the SLN before tumor mass formation has occurred. Here we investigated the optimal physicochemical ranges of chemotherapeutic agents’ solvents with the aim of increasing treatment efficacy using the LDDS. We found that an appropriate osmotic pressure range for drug administration was 700–3,000 kPa, with a viscosity < 40 mPa⋅s. In these physicochemical ranges, expansion of lymphatic vessels and sinuses, drug retention, and subsequent antitumor effects could be more precisely controlled. Furthermore, the antitumor effects depended on the tumor progression stage in the SLN, the injection rate, and the volumes of administered drugs. We anticipate these optimal ranges to be a starting point for developing more effective drug regimens to treat metastatic LN with the LDDS.

Seven Genes Associated With Lymphatic Metastasis in Thyroid Cancer That Is Linked to Tumor Immune Cell Infiltration

Objective

Since there are few studies exploring genes associated with lymphatic metastasis of thyroid carcinoma (THCA), this study was conducted to explore genes associated with lymphatic metastasis of THCA and to investigate the relationship with immune infiltration.

Methods

Differentially expressed genes associated with THCA lymphatic metastasis were analyzed based on The Cancer Genome Atlas Program (TCGA) database; a protein-protein interaction(PPI)network was constructed to screen for pivotal genes. Based on the identified hub genes, their expression in THCA with and without lymphatic metastasis were determined. Functional enrichment analysis was performed. The correlation between the identified genes and immune cell infiltration was explored. LASSO logistic regression analysis was performed to determine the risk score of the most relevant gene constructs and multifactor COX regression analysis based on genes in the risk score formula.

Results

A total of 115 genes were differentially expressed in THCA with and without lymphatic metastasis, including 28 upregulated genes and 87 downregulated genes. The PPI network identified seven hub genes (EVA1A, TIMP1, SERPINA1, FAM20A, FN1, TNC, MXRA8); the expression of all seven genes was upregulated in the group with lymphatic metastasis; Immuno-infiltration analysis showed that all seven genes were significantly positively correlated with macrophage M1 and NK cells and negatively correlated with T-cell CD4+ and myeloid dendritic cells. LASSO logistic regression analysis identified the five most relevant genes (EVA1A, SERPINA1, FN1, TNC, MXRA8), and multi-factor COX regression analysis showed EVA1A, SERPINA1 and FN1 as independent prognostic factors.

Conclusion

Seven genes were associated with lymphatic metastasis of THCA and with tumor immune cell infiltration.

Single-Cell DNA Sequencing Reveals Punctuated and Gradual Clonal Evolution in Hepatocellular Carcinoma

BACKGROUND & AIMS

Copy number alterations (CNAs), elicited by genome instability, are a major source of intratumor heterogeneity. How CNAs evolve in hepatocellular carcinoma (HCC) remains unknown.

METHODS

We performed single-cell DNA sequencing (scDNA-seq) on 1275 cells isolated from 10 patients with HCC, ploidy-resolved scDNA-seq on 356 cells from 1 additional patient, and single-cell RNA sequencing on 27,344 cells from 3 additional patients. Three statistical fitting models were compared to investigate the CNA accumulation pattern.

RESULTS

Cells in the tumor were categorized into the following 3 subpopulations: euploid, pseudoeuploid, and aneuploid. Our scDNA-seq analysis revealed that CNA accumulation followed a dual-phase copy number evolution model, that is, a punctuated phase followed by a gradual phase. Patients who exhibited prolonged gradual phase showed higher intratumor heterogeneity and worse disease-free survival. Integrating bulk RNA sequencing of 17 patients with HCC, published datasets of 1196 liver tumors, and immunohistochemical staining of 202 HCC tumors, we found that high expression of CAD, a gene involved in pyrimidine synthesis, was correlated with rapid tumorigenesis and reduced survival. The dual-phase copy number evolution model was validated by our single-cell RNA sequencing data and published scDNA-seq datasets of other cancer types. Furthermore, ploidy-resolved scDNA-seq revealed the common clonal origin of diploid- and polyploid-aneuploid cells, suggesting that polyploid tumor cells were generated by whole genome doubling of diploid tumor cells.

CONCLUSIONS

Our work revealed a novel dual-phase copy number evolution model, showed HCC with longer gradual phase was more severe, identified CAD as a promising biomarker for early recurrence of HCC, and supported the diploid origin of polyploid HCC.

A Novel and Effective Model to Predict Skip Metastasis in Papillary Thyroid Carcinoma Based on a Support Vector Machine

INTRODUCTION

Skip metastasis, referred to as lymph node metastases to the lateral neck compartment without involvement of the central compartment, is generally unpredictable in papillary thyroid carcinoma (PTC). This study aims to establish an effective predictive model for skip metastasis in PTC.

METERIALS AND METHODS

Retrospective analysis was performed of clinical samples from 18192 patients diagnosed with thyroid cancer between 2016 to 2020. The First Affiliated Hospital of Wenzhou Medical University. The lateral lymph node metastasis was occureed in the training set (630 PTC patients) and validation set (189 PTC patients). The univariate and multivariate analyses were performed to detect the predictors of skip metastasis and the support vector machine (SVM) was used to establish a model to predict skip metastasis.

RESULTS

The rate of skip metastasis was 13.3% (84/631). Tumor size (≤10 mm), upper location, Hashimoto's thyroiditis, extrathyroidal extension, absence of BRAFV600E mutation, and less number of central lymph node dissection were considered as independent predictors of skip metastasis in PTC. For the training set, these predictors performed with 91.7% accuracy, 86.4% sensitivity, 92.2% specificity, 45.2% positive predictive value (PPV), and 98.9% negative predictive value (NPV) in the model. Meanwhile, these predictors showed 91.5% accuracy,71.4% sensitivity, 93.1% specificity, 45.5% PPV, and 97.6% NPV in validation set.

CONCLUSION

This study screened the predictors of the skip lateral lymph node metastasis and to establish an effective and economic predictive model for skip metastasis in PTC. The model can accurately distinguish the skip metastasis in PTC using a simple and affordable method, which may have potential for daily clinical application in the future.

Delineating the intra-patient heterogeneity of molecular alterations in treatment-naïve colorectal cancer with peritoneal carcinomatosis

In a non-negligible number of patients with metastatic colorectal cancer (mCRC), the peritoneum is the predominant site of dissemination. Cure can be achieved by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), but this procedure is associated with long-term morbidity and high relapse rates. Thus, there is a pressing need for improved therapeutic strategies and complementary biomarkers. The present study explored the molecular heterogeneity in mCRC with peritoneal carcinomatosis (PC), and the potential clinical implications thereof. Multi-region immunohistochemical profiling and deep targeted DNA-sequencing was performed on chemotherapy-naïve tumours from seven patients with synchronous colorectal PC who underwent CRS and HIPEC. In total, 88 samples (5-19 per patient) were analysed, representing primary tumour, lymph node metastases, tumour deposits, PC and liver metastases. Expression of special AT-rich sequence-binding protein 2 (SATB2), a marker of colorectal lineage, was lacking in the majority of cases, and a conspicuous intra-patient heterogeneity was denoted for expression of the proposed prognostic and predictive biomarker RNA-binding motif protein 3 (RBM3). Loss of mismatch repair proteins MLH1 and PSM2, observed in one case, was concordant with microsatellite instability and the highest tumour mutational burden. When present in a patient, mutations in key CRC driver genes, i.e., KRAS, APC and TP53, were homogenously distributed across all samples, while less common mutations were more heterogenous. On the same note, copy number variations showed intra-patient as well inter-patient heterogeneity. In two out of seven cases, hierarchical clustering revealed that samples from the PC and lymph node metastases were more similar to each other than to the primary tumour. In summary, these findings should encourage additional studies addressing the potential distinctiveness of mCRC with PC, which might pave the way for improved personalized treatment of these patients.

Molecular mechanisms of cancer metastasis via the lymphatic versus the blood vessels

Cancer metastasis is the process by which primary cancer cells invade through the lymphatic or blood vessels to distant sites. The molecular mechanisms by which cancer cells spread either through the lymphatic versus blood vessels or both are not well established. Two major developments have helped us to understand the process more clearly. First, the development of the sentinel lymph node (SLN) concept which is well established in melanoma and breast cancer. The SLN is the first lymph node in the draining nodal basin to receive cancer cells. Patients with a negative SLN biopsy show a significantly lower incidence of distant metastasis, suggesting that the SLN may be the major gateway for cancer metastasis in these cancer types. Second, the discovery and characterization of several biomarkers including VEGF-C, LYVE-1, Podoplanin and Prox-1 have opened new vistas in the understanding of the induction of lymphangiogenesis by cancer cells. Cancer cells must complete multiple steps to invade the lymphatic system, some of which may be enabled by the evolution of new traits during cancer progression. Thus, cancer cells may spread initially through the main gateway of the SLN, from which evolving cancer clones can invade the blood vessels to distant sites. Cancer cells may also enter the blood vessels directly, bypassing the SLN to establish distant metastases. Future studies need to pinpoint the molecules that are used by cancer cells at different stages of metastasis via different routes so that specific therapies can be targeted against these molecules, with the goal of stopping or preventing cancer metastasis.

Molecular differences between lymph nodes and distant metastases compared with primaries in colorectal cancer patients

Lymph nodes (LNs) and distant metastases can arise from independent subclones of the primary tumor. Herein, we characterized the molecular landscape and the differences between LNs, distant metastases and primary colorectal cancers (CRCs). Samples were analyzed using next generation sequencing (NGS, MiSeq on 47 genes, NextSeq on 592 genes) and immunohistochemistry. Tumor mutational burden (TMB) was calculated based on somatic nonsynonymous missense mutations, and microsatellite instability (MSI) was evaluated by NGS of known MSI loci. In total, 11,871 samples were examined, comprising primaries (N = 5862), distant (N = 5605) and LNs metastases (N = 404). The most frequently mutated genes in LNs were TP53 (72%), APC (61%), KRAS (39%), ARID1A (20%), PIK3CA (12%). LNs showed a higher mean TMB (13 mut/MB) vs distant metastases (9 mut/MB, p < 0.0001). TMB-high (≥17mut/MB) and MSI-H (8.8% and 6.9% vs 3.7%, p < 0.001 and p = 0.017, respectively) classifications were more frequent in primaries and LNs vs distant metastases (9.5% and 8.8% vs 4.2%, p < 0.001 and p = 0.001, respectively). TMB-high is significantly more common in LNs vs distant metastases and primaries (P < 0.0001), regardless MSI-H status. Overall, LNs showed significantly different rates of mutations in APC, KRAS, PI3KCA, KDM6A, and BRIP1 (p < 0.01) vs primaries, while presenting a distinct molecular profile compared to distant metastases. Our cohort of 30 paired samples confirmed the molecular heterogeneity between primaries, LNs, and distant metastases. Our data support the hypothesis that lymphatic and distant metastases harbor different mutational landscape. Our findings are hypothesis generating and need to be examined in prospective studies.

Mechanisms and Clinical Significance of Tumor Lymphatic Invasion

Tumor-associated lymphatic vessels play an important role in tumor progression, mediating lymphatic dissemination of malignant cells to tumor-draining lymph nodes and regulating tumor immunity. An early, necessary step in the lymphatic metastasis cascade is the invasion of lymphatic vessels by tumor cell clusters or single tumor cells. In this review, we discuss our current understanding of the underlying cellular and molecular mechanisms, which include tumor-specific as well as normal, developmental and immunological processes “hijacked” by tumor cells to gain access to the lymphatic system. Furthermore, we summarize the prognostic value of lymphatic invasion, discuss its relationship with local recurrence, lymph node and distant metastasis, and highlight potential therapeutic options and challenges.

Modeling colorectal cancer evolution

Understanding cancer evolution provides a clue to tackle therapeutic difficulties in colorectal cancer. In this review, together with related works, we will introduce a series of our studies, in which we constructed an evolutionary model of colorectal cancer by combining genomic analysis and mathematical modeling. In our model, multiple subclones were generated by driver mutation acquisition and subsequent clonal expansion in early-stage tumors. Among the subclones, the one obtaining driver copy number alterations is endowed with malignant potentials to constitute a late-stage tumor in which extensive intratumor heterogeneity is generated by the accumulation of neutral mutations. We will also discuss how to translate our understanding of cancer evolution to a solution to the problem related to therapeutic resistance: mathematical modeling suggests that relapse caused by acquired resistance could be suppressed by utilizing clonal competition between sensitive and resistant clones. Considering the current rate of technological development, modeling cancer evolution by combining genomic analysis and mathematical modeling will be an increasingly important approach for understanding and overcoming cancer.

IDH Mutation Subgroup Status Associates with Intratumor Heterogeneity and the Tumor Microenvironment in Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is highly heterogeneous. Here, the authors perform exome sequencing and bulk RNA sequencing on 73 tumor regions from 14 ICC patients to portray the multi-faceted intratumor heterogeneity (ITH) landscape of ICC. The authors show that ITH is highly concordant across genomic, transcriptomic, and immune levels. Comparison of these data to 8 published datasets reveals significantly higher degrees of ITH in ICC than hepatocellular carcinoma. Remarkably, the authors find that high-ITH tumors highly overlap with the IDH (isocitrate dehydrogenase)-mutant subgroup (IDH-SG), comprising of IDH-mutated tumors and IDH-like tumors, that is, those IDH-wildtype tumors that exhibit similar molecular profiles to the IDH-mutated ones. Furthermore, IDH-SG exhibits less T cell infiltration and lower T cell cytotoxicity, indicating a colder tumor microenvironment (TME). The higher ITH and colder TME of IDH-SG are successfully validated by single-cell RNA sequencing on 17 503 cells from 4 patients. Collectively, the study shows that IDH mutant subgroup status, rather than IDH mutation alone, is associated with ITH and the TME of ICC tumors. The results highlight that IDH-like patients may also benefit from IDH targeted therapies and provide important implications for the diagnosis and treatment of ICC.

Spatiotemporal Immune Landscape of Colorectal Cancer Liver Metastasis at Single-Cell Level

Liver metastasis, the leading cause of colorectal cancer mortality, exhibits a highly heterogeneous and suppressive immune microenvironment. Here, we sequenced 97 matched samples by using single-cell RNA-seq and Spatial Transcriptomics. Strikingly, metastatic microenvironment underwent remarkable spatial reprogramming of immunosuppressive cells such as MRC1+ CCL18+ M2-like macrophages. We further developed scMetabolism, a computational pipeline for quantifying single-cell metabolism, and observed that those macrophages harbored enhanced metabolic activity. Interestingly, neoadjuvant chemotherapy could block this status and restore the antitumor immune balance in responsive patients, while the non-responsive patients deteriorated into a more suppressive one. Our work described the immune evolution of metastasis and uncovered the black box of how tumors respond to neoadjuvant chemotherapy.

Follistatin-Like 3 Correlates With Lymph Node Metastasis and Serves as a Biomarker of Extracellular Matrix Remodeling in Colorectal Cancer

Background

As a heterogeneous disease, colorectal cancer (CRC) presents a great challenge to individualized treatment due to its lymph node metastasis (LNM). Existing studies have shown that immune and stromal components in extracellular matrix (ECM) act as important part in tumorigenicity and progression, while their roles in LNM have not been fully elucidated. Here, crucial ECM-related genes responsible for LNM in CRC were selected by multi-omics analysis.

Methods

Firstly, we characterized the immune infiltration landscape of CRC samples from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases by using ssGSEA algorithm. The CRC patients were divided into several immune subgroups by hierarchical clustering analyses. Then, differential genes were identified among immune subgroups and CRC vs. normal tissues in TCGA and GEO GSE39582 cohorts, respectively. Next, weighted correlation network analysis (WGCNA) was employed to construct a co-expression network to find LNM-related modules and hub genes. Subsequently, we evaluated the clinical value of hub gene in prognostic prediction and chemotherapy/immunotherapy. Besides, the protein level of key gene was verified in an external cohort from our center. Finally, we explored the underlying mechanism of FSTL3-mediated LNM by Gene function annotation and correlation analysis.

Results

Two immune subgroups, namely Immunity_High and Immunity_Low, were defined among the two CRC cohorts using ssGSEA algorithm, respectively. Based on the two immune subgroups, 2,635 overlapping differentially expressed genes were obtained from two cohorts, which were sequentially subjected to WGCNA and univariate Cox regression analysis. Ultimately, FSTL3 was selected as the key gene. Here, we first confirmed that overexpression of FSTL3 correlated with LNM and worse prognosis in CRC and was verified at the protein level in the external validation cohort. Moreover, FSTL3 expression showed strongly positive correlation with immune and stromal components in ECM. We furthermore found that FSTL3 may accelerate LNM through the formation of inhibitory immune microenvironment via promoting macrophage and fibroblast polarization and T cell exhaustion. Interestingly, high FSTL3 expression is linked to chemoresistance, but immunotherapy-sensitive.

Conclusion

FSTL3 is identified as a biomarker for ECM remodeling and worse clinical outcomes for the first time in CRC and is also a potential immunotherapeutic target to block LNM for CRC.

Comparative analysis of clonal evolution among patients with right- and left-sided colon and rectal cancer

Tumor multiregion sequencing reveals intratumor heterogeneity (ITH) and clonal evolution playing a key role in tumor progression and metastases. Large-scale high-depth multiregional sequencing of colorectal cancer, comparative analysis among patients with right-sided colon cancer (RCC), left-sided colon cancer (LCC), and rectal cancer (RC), as well as the study of lymph node metastasis (LN) with extranodal tumor deposits (ENTDs) from evolutionary perspective remain weakly explored. Here, we recruited 68 patients with RCC (18), LCC (20), and RC (30). We performed high-depth whole-exome sequencing of 206 tumor regions including 176 primary tumors, 19 LN, and 11 ENTD samples. Our results showed ITH with a Darwinian pattern of evolution and the evolution pattern of LCC and RC was more complex and divergent than RCC. Genetic and evolutionary evidences found that both LN and ENTD originated from different clones. Moreover, ENTD was a distinct entity from LN and evolved later.

MesKit: a tool kit for dissecting cancer evolution of multi-region tumor biopsies through somatic alterations

Background

Multi-region sequencing (MRS) has been widely used to analyze intra-tumor heterogeneity (ITH) and cancer evolution. However, comprehensive analysis of mutational data from MRS is still challenging, necessitating complicated integration of a plethora of computational and statistical approaches.

Findings

Here, we present MesKit, an R/Bioconductor package that can assist in characterizing genetic ITH and tracing the evolutionary history of tumors based on somatic alterations detected by MRS. MesKit provides a wide range of analysis and visualization modules, including ITH evaluation, metastatic route inference, and mutational signature identification. In addition, MesKit implements an auto-layout algorithm to generate phylogenetic trees based on somatic mutations. The application of MesKit for 2 reported MRS datasets of hepatocellular carcinoma and colorectal cancer identified known heterogeneous features and evolutionary patterns, together with potential driver events during cancer evolution.

Conclusions

In summary, MesKit is useful for interpreting ITH and tracing evolutionary trajectory based on MRS data. MesKit is implemented in R and available at https://bioconductor.org/packages/MesKit under the GPL v3 license.

Organ tropism in solid tumor metastasis: an updated review

Tumors are equipped with a highly complex machinery of interrelated events so as to adapt to hazardous conditions, preserve a growing cell mass and thrive at the site of metastasis. Tumor cells display metastatic propensity toward specific organs where the stromal milieu is appropriate for their further colonization. Effective colonization relies on the plasticity of tumor cells in adapting to the conditions of the new area by reshaping their epigenetic landscape. Breast cancer cells, for instance, are able to adopt brain-like or epithelial/osteoid features in order to pursue effective metastasis into brain and bone, respectively. The aim of this review is to discuss recent insights into organ tropism in tumor metastasis, outlining potential strategies to address this driver of tumor aggressiveness.

Progression of Metastasis through Lymphatic System

Lymph nodes are the most common sites of metastasis in cancer patients. Nodal disease status provides great prognostic power, but how lymph node metastases should be treated is under debate. Thus, it is important to understand the mechanisms by which lymph node metastases progress and how they can be targeted to provide therapeutic benefits. In this review, we focus on delineating the process of cancer cell migration to and through lymphatic vessels, survival in draining lymph nodes and further spread to other distant organs. In addition, emerging molecular targets and potential strategies to inhibit lymph node metastasis are discussed.

Metastatic Spread in Prostate Cancer Patients Influencing Radiotherapy Response

Radiotherapy and surgery are curative treatment options for localized prostate cancer (PCa) with a 5-year survival rate of nearly 100%. Once PCa cells spread into distant organs, such as bone, the overall survival rate of patients drops dramatically. The metastatic cascade and organotropism of PCa cells are regulated by different cellular subtypes, organ microenvironment, and their interactions. This cross-talk leads to pre-metastatic niche formation that releases chemo-attractive factors enforcing the formation of distant metastasis. Biological characteristics of PCa metastasis impacting on metastatic sites, burden, and latency is of clinical relevance. Therefore, the implementation of modern hybrid imaging technologies into clinical routine increased the sensitivity to detect metastases at earlier stages. This enlarged the number of PCa patients diagnosed with a limited number of metastases, summarized as oligometastatic disease. These patients can be treated with androgen deprivation in combination with local-ablative radiotherapy or radiopharmaceuticals directed to metastatic sites. Unfortunately, the number of patients with disease recurrence is high due to the enormous heterogeneity within the oligometastatic patient population and the lack of available biomarkers with predictive potential for metastasis-directed radiotherapy. Another, so far unmet clinical need is the diagnosis of minimal residual disease before onset of clinical manifestation and/or early relapse after initial therapy. Here, monitoring of circulating and disseminating tumor cells in PCa patients during the course of radiotherapy may give us novel insight into how metastatic spread is influenced by radiotherapy and vice versa. In summary, this review critically compares current clinical concepts for metastatic PCa patients and discuss the implementation of recent preclinical findings improving our understanding of metastatic dissemination and radiotherapy resistance into standard of care.

Molecular Alterations in Metastatic Ovarian Cancer From Gastrointestinal Cancer

Reports indicate that most metastatic ovarian cancer (MOC) originates from gastrointestinal cancer (GIC). Notably, GICs metastasize to the ovary frequently via 3 main routes including hematogenous spread, lymphogenous spread, and transcoelomic spread. Nonetheless, the mechanism of the progression remains unknown, and only a handful of literature exists on the molecular alteration implicated in MOC from GIC. This work collected existing evidence and literature on the vital molecules of the metastatic pathway and systematically analyzed them geared toward exploring the mechanism of the metastatic pathway of MOC. Further, this review described dominating molecular alteration in the metastatic process from cancer cells detaching away from lesions to arrive at the ovary, including factors for regulating signaling pathways in epithelial-interstitial transformation, invading, and surviving in the circulatory system or abdominal cavity. We interrogated the basis of the ovary as a distant metastatic site. This article provides new insights into the metastatic pathway and generates novel therapeutic targets for effective treatment and satisfactory outcomes in GIC patients.

LncRNA AC010789.1 Promotes Colorectal Cancer Progression by Targeting MicroRNA-432-3p/ZEB1 Axis and the Wnt/β-Catenin Signaling Pathway

Accumulating literatures have indicated that long non-coding RNAs (lncRNAs) are crucial molecules in tumor progression in various human cancers, including colorectal cancer (CRC). However, the clinical significance and regulatory mechanism of a vast majority of lncRNAs in CRC remain to be determined. The current study aimed to explore the function and molecular mechanism of lncRNA AC010789.1 in CRC progression. AC010789.1 found to be overexpressed in CRC tissues and cells. High expression of AC010789.1 was associated with lymph node metastasis and poor prognosis. Moreover, AC010789.1 silencing inhibited proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in vitro as well as tumorigenesis and metastasis in vivo. Mechanistically, we demonstrated that repression of AC010789.1 promoted miR-432-3p expression, and miR-432-3p directly binds to ZEB1. We then proved the anti-tumor role of miR-432-3p in CRC, showing that the inhibitory effect of AC010789.1 knockdown on CRC cells was achieved by the upregulation of miR-432-3p but downregulation of ZEB1. We also established that silencing AC010789.1 suppressed the Wnt/β-catenin signaling pathway. However, this inhibitory effect was partially counteracted by inhibition of miR-432-3p. In summary, these results reveal that silencing AC010789.1 suppresses CRC progression via miR-432-3p-mediated ZEB1 downregulation and suppression of the Wnt/β-catenin signaling pathway, highlighting a potentially promising strategy for CRC treatment.