Prognostic value of radiologically enlarged lymph nodes in node-negative colon cancer

Mesenteric benign lymph node enlargement in colorectal cancer: Friend or foe?

INTRODUCTION

Benign lymph node enlargement (BLNE) is common in colorectal cancer; however, few studies have investigated its influence on prognosis, clinicopathological features, and pathogenesis.

METHODS

A cohort study was conducted to analyze the clinicopathologic features and prognosis of colorectal cancer patients, categorized based on the presence or absence of BLNE. Given the correlation between lymph nodes and immune response, immunohistochemistry, transcriptome analysis, and exon sequencing were employed to further investigate the differences in the immune microenvironment of primary tumors.

RESULTS

Overall, 630 AJCC stage I/II patients were included in the study, with 131 in the BLNE group and 499 in the Non-BLNE (NBLNE) group. Patients in the BLNE group were found to have a significantly better disease-free survival (DFS) (hazard ratio [HR] 0.44, P = 0.016) and overall survival (OS) (HR 0.46, P = 0.011) than those in the NBLNE group. Pathologically, compared with the NBLNE group, the BLNE group had more mature tertiary lymphoid structures (66.7 % vs. 36.5 %, P = 0.002) and higher immunoscores (18.8 % vs. 2.1 %, P = 0.004) in primary tumor tissue. Also, transcriptome analysis showed that, compared with NBLNE, the genes upregulated in BLNE were enriched in immune-related pathways, such as adaptive immune response and immuno-regulatory interactions. Whole-exon sequencing analysis revealed a higher tumor mutation burden (TMB) in the BLNE group [6.03 (5.59, 7.59) vs. 5.33 (4.62, 6.34), P = 0.025].

CONCLUSION

BLNE is positively associated with the prognosis of colorectal cancer, possibly because patients with BLNE have a stronger anti-tumor immune response.

Small arteriole sign: an imaging feature for staging T4a colon cancer

OBJECTIVES

By analyzing the distribution of existing and newly proposed staging imaging features in pT1-3 and pT4a tumors, we searched for a salient feature and validated its diagnostic performance.

METHODS

Preoperative multiphase contrast-enhanced CT images of the training cohort were retrospectively collected at three centers from January 2016 to December 2017. We used the chi-square test to analyze the distribution of several stage-related imaging features in pT1-3 and pT4a tumors, including small arteriole sign (SAS), outer edge of the intestine, tumor invasion range, and peritumoral adipose tissue. Preoperative multiphase contrast-enhanced CT images of the validation cohort were retrospectively collected at Beijing Cancer Hospital from January 2018 to December 2018. The diagnostic performance of the selected imaging feature, including accuracy, sensitivity, and specificity, was validated and compared with the conventional clinical tumor stage (cT) by the McNemar test.

RESULTS

In the training cohort, a total of 268 patients were enrolled, and only SAS was significantly different between pT1-3 and pT4a tumors. The accuracy, sensitivity, and specificity of the SAS and conventional cT in differentiating T1-3 and T4a tumors were 94.4%, 81.6%, and 97.3% and 53.7%, 32.7%, and 58.4%, respectively (all p < 0.001). In the validation cohort, a total of 135 patients were collected. The accuracy, sensitivity, and specificity of the SAS and the conventional cT were 93.3%, 76.2%, and 96.5% and 62.2%, 38.1%, and 66.7%, respectively (p < 0.001, p = 0.021, p < 0.001).

CONCLUSION

Small arteriole sign positivity, an indirect imaging feature of serosa invasion, may improve the accuracy of identifying T4a colon cancer.

CLINICAL RELEVANCE STATEMENT

Small arteriole sign helps to distinguish T1-3 and T4a colon cancer and further improves the accuracy of preoperative CT staging of colon cancer.

KEY POINTS

• The accuracy of preoperative CT staging of colon cancer is not ideal, especially for T4a tumors. • Small arteriole sign (SAS) is a newly defined imaging feature that shows the appearance of tumor-supplying arterioles at the site where they penetrate the intestine wall. • SAS is an indirect imaging marker of tumor invasion into the serosa with a great value in distinguishing between T1-3 and T4a colon cancer.

Prognostic Significance of Enlarged Lymph Nodes in Stage II Colorectal Cancer

BACKGROUND

Many studies have reported a correlation between lymph node metastasis and prognosis in patients with colorectal cancer. However, the clinical significance of enlarged lymph nodes for prognosis has scarcely been explored.

OBJECTIVE

This study aimed to assess the clinical significance of enlarged lymph nodes in stage II colorectal cancer.

DESIGN

This is a multicenter retrospective observational study with a median follow-up period of 66.8 months.

SETTINGS

Patients' medical records were retrospectively collected from the Japanese Study Group for Postoperative Follow-up of Colorectal Cancer database.

PATIENTS

This study included 2212 patients with stage II colorectal cancer who underwent surgical resection between January 2009 and December 2012. Patients were classified into the enlarged lymph node and nonenlarged lymph node groups and their data were compared.

MAIN OUTCOME MEASURES

Clinicopathological characteristics and prognoses of the 2 groups were compared. The main outcomes measured were recurrence-free survival and overall survival.

RESULTS

The enlarged lymph node group showed significantly better overall survival and recurrence-free survival in pT4b cases but not in pT3 or pT4a cases. In pT4b cases, an enlarged lymph node (HR, 0.53; 95% CI, 0.29-0.98) was an independent prognostic factor for longer recurrence-free survival, whereas a rectal lesion (HR, 3.46; 95% CI, 1.90-6.29) was an independent prognostic factor for shorter recurrence-free survival. An enlarged lymph node was associated with a lower distant recurrence rate (HR, 0.49; 95% CI, 0.26-0.92) and a tendency to correlate with better overall survival (HR, 0.50; 95% CI, 0.22-1.14).

LIMITATIONS

The retrospective design may have increased the risk of selection bias. Inadequate information regarding enlarged lymph nodes is another study limitation.

CONCLUSIONS

This study showed that enlarged lymph nodes are associated with a favorable prognosis in patients with pT4b stage II colorectal cancer. See Video Abstract at http://links.lww.com/DCR/C246 .

IMPORTANCIA PRONSTICA DE LOS GANGLIOS LINFTICOS AGRANDADOS EN EL CNCER COLORRECTAL EN ESTADIO II

ANTECEDENTES:Muchos estudios han informado una correlación entre la metástasis en los ganglios linfáticos y el pronóstico en pacientes con cáncer colorrectal. Sin embargo, apenas se ha explorado la importancia clínica de los ganglios linfáticos agrandados para el pronóstico.OBJETIVO:El objetivo fue evaluar la importancia clínica de los ganglios linfáticos agrandados en el cáncer colorrectal en estadio II.DISEÑO:Este es un estudio observacional retrospectivo multicéntrico con una mediana de seguimiento de 66,8 meses.CONFIGURACIÓN:Los registros médicos de los pacientes se recopilaron retrospectivamente de la base de datos del Grupo de estudio japonés para el seguimiento posoperatorio del cáncer colorrectal.PACIENTES:Incluimos 2212 pacientes con cáncer colorrectal en estadio II que se sometieron a resección quirúrgica entre enero de 2009 y diciembre de 2012. Los pacientes se clasificaron en grupos de ganglios linfáticos agrandados y no agrandados y se compararon sus datos.PRINCIPALES MEDIDAS DE RESULTADO:Se compararon las características clinicopatológicas y los pronósticos de los dos grupos. Los principales resultados medidos fueron la supervivencia sin recurrencia y la supervivencia general.RESULTADOS:El grupo de ganglios linfáticos agrandados mostró una supervivencia general significativamente mejor y una supervivencia libre de recurrencia en los casos pT4b, pero no en los casos pT3 ni pT4a. En los casos de pT4b, el agrandamiento de los ganglios linfáticos (CRI, 0,53; IC 95 %, 0,29-0,98) fue un factor pronóstico independiente para una supervivencia sin recidiva más prolongada, mientras que la lesión rectal (CRI, 3,46; IC 95%, 1,90-6,29) fue un factor pronóstico independiente para RFS más cortos. Los ganglios linfáticos agrandados se relacionaron con una tasa más baja de recurrencia a distancia (CRI, 0,49; IC 95%, 0,26-0,92) y una tendencia a correlacionarse con una mejor supervivencia general (CRI, 0,50; IC 95%, 0,22-1,14).LIMITACIONES:El diseño retrospectivo puede haber aumentado el riesgo de sesgo de selección. La información inadecuada sobre el agrandamiento de los ganglios linfáticos es otra limitación del estudio.CONCLUSIONES:Este estudio mostró que los ganglios linfáticos agrandados están asociados con un pronóstico favorable en pacientes con cáncer colorrectal pT4b en estadio II. Consulte Video Resumen en http://links.lww.com/DCR/C246 . ( Traducción - Dr. Mauricio Santamaria ).

Radiological lymph-node size improves the prognostic value of systemic inflammation index in rectal cancer with pathologically negative nodes

BACKGROUND

The relationship between the radiological lymph node (rLN) size and survival outcome in node-negative rectal cancer is still uncertain. In this study, we aimed to explore the role of enlarged rLN in predicting the survival of node-negative rectal cancers.

METHODS

We retrospectively reviewed the records of 722 node-negative rectal cancer who underwent curative resection. Factors associated with DFS (disease-free survival) and CSS (cancer-specific survival) were assessed with univariate and multivariate analysis. Survival analysis was performed according to presence with or without enlarged rLN. Combining rLN with NLR as a new index-inflammation immune score (IIS) for predicting survival. Comparing different models to assess the predictive powers.

RESULTS

A total of 119 patients had tumor recurrence and 73 patients died due to cancer. Patients with enlarged rLN (≥5 mm) was significantly associated with better DFS (HR:0.517, 95%CI:0.339-0.787, p = 0.002) and CSS (HR:0.43, 95%CI:0.242-0.763, p = 0.004). The risk factors of recurrence were rLN, neutrophil-lymphocyte ratio (NLR), CEA level, and distance from the anal verge. The risk of recurrence increased by 1.88- and 2.83-fold for the high score in IIS compared with the low and intermediate score group (All p < 0.001). Similarly, the high score in IIS also increased the risk of cancer-specific death. In the model comparison, the AIC and LR were improved by including the rLN into the NLR model for DFS and CSS prediction (All p < 0.05).

CONCLUSIONS

Node-negative rectal cancer patients with enlarged rLN had a better survival outcome. IIS might be a more comprehensive and complete inflammation immune index for survival prediction.

Correlation and prognostic value of CT-detected extramural venous invasion and pathological lymph-vascular invasion in colon cancer

PURPOSE

To explore the association between CT-detected extramural vascular invasion (ctEMVI) and lymph-vascular invasion (LVI) in colon cancer, and analyze the prognostic value of ctEMVI in different conditions of LVI.

METHODS

This single-center, retrospective study included 448 colon cancer patients from January 2015 to December 2017. Preoperative CT features and clinical and pathological data were collected. Associations between ctEMVI and LVI were tested. Univariate and multivariate logistic regression was performed. Multivariate Cox regression was performed adjusted with propensity score(PS). Kaplan-Meier method was used to compare survival differences between the ctEMVI and LVI groups. A 1:1 patient pairing was conducted using PS matching to assess the prognostic effect of ctEMVI in LVI subgroups.

RESULTS

Among the 448 patients, there were 261 men and 187 women, with an average age of 63 ± 12 years. The coincidence rate of ctEMVI and LVI was 73.9%. The k coefficient for identifying ctEMVI was 0.84. ctEMVI and LVI were both independent risk factors for overall survival (ctEMVI: HR 2.8, 95% CI 1.5-5.5; LVI: HR 2.2, 95% CI 1.2-4.1) and metastasis-free survival (ctEMVI: HR 3.3, 95% CI 1.7-6.4; LVI: HR 2.4, 95% CI 1.3-4.5) adjusted with PS. In the LVI(+) subgroup, the prognosis of ctEMVI(+) was significantly worse than that of ctEMVI(-); in the LVI(-) subgroup, the prognosis of different ctEMVI states was similar.

CONCLUSION

ctEMVI is an independent prognostic risk factor and has different prognostic value in different LVI states. It is recommended to perform the evaluation in routine work, especially for patients with positive LVI.