Metastatic spread pattern after curative colorectal cancer surgery. A retrospective, longitudinal analysis

Exploring the impact of circRNAs on cancer glycolysis: Insights into tumor progression and therapeutic strategies

Cancer cells exhibit altered metabolic pathways, prominently featuring enhanced glycolytic activity to sustain their rapid growth and proliferation. Dysregulation of glycolysis is a well-established hallmark of cancer and contributes to tumor progression and resistance to therapy. Increased glycolysis supplies the energy necessary for increased proliferation and creates an acidic milieu, which in turn encourages tumor cells' infiltration, metastasis, and chemoresistance. Circular RNAs (circRNAs) have emerged as pivotal players in diverse biological processes, including cancer development and metabolic reprogramming. The interplay between circRNAs and glycolysis is explored, illuminating how circRNAs regulate key glycolysis-associated genes and enzymes, thereby influencing tumor metabolic profiles. In this overview, we highlight the mechanisms by which circRNAs regulate glycolytic enzymes and modulate glycolysis. In addition, we discuss the clinical implications of dysregulated circRNAs in cancer glycolysis, including their potential use as diagnostic and prognostic biomarkers. All in all, in this overview, we provide the most recent findings on how circRNAs operate at the molecular level to control glycolysis in various types of cancer, including hepatocellular carcinoma (HCC), prostate cancer (PCa), colorectal cancer (CRC), cervical cancer (CC), glioma, non-small cell lung cancer (NSCLC), breast cancer, and gastric cancer (GC). In conclusion, this review provides a comprehensive overview of the significance of circRNAs in cancer glycolysis, shedding light on their intricate roles in tumor development and presenting innovative therapeutic avenues.

Evaluating the Role of Methylated Circulating Tumor DNA in Combination With Pathological Prognostic Factors for Predicting Recurrence of Colorectal Cancer

Background

Colorectal cancer (CRC) has a high rate of recurrence, in particular for advanced disease, but prognosis based on staging and pathology at surgery can have limited efficacy. The presence of circulating tumor DNA (ctDNA) at diagnosis could be used to improve the prediction for disease recurrence.

Objectives

To assess the impact of detecting methylated BCAT1/IKZF1 ctDNA at diagnosis in combination with demographic, lifestyle, clinical factors and tumor pathology, to assess predictive value for recurrence.

Design

A retrospective cohort study.

Methods

The cohort included 180 patients (36 with recurrent CRC), who had undergone complete treatment and surveillance for a minimum of 3 years. Participant clinical details and ctDNA methylated BCAT1/IKZF1 results were compared between those with and without recurrence, and cox regression analysis assessed each factor on disease-free survival.

Results

Clinical factors independently associated with reduced disease-free survival included nodal involvement (HR = 3.83, 95% CI 1.56-9.43, P = .003), M1 stage (HR = 4.41, 95% CI 1.18-16.45, P = .027), a resection margin less than 2 mm (HR = 4.60, 95% CI 1.19-17.76, P = .027), perineural involvement (HR = 2.50, 95% CI 1.01-6.17, P = .047) and distal tumors (HR = 3.13, 95% CI 1.07-9.18, P = .037). Methylated BCAT1/IKZF1 was detected in 51.7% (93/180) of pre-treatment plasma samples. When a positive ctDNA finding was considered in combination with these clinical prognostic factors, there was improved predictive power of recurrence for patients with perineural involvement (HR = 4.44, 95% CI 1.92-10.26, P < .001), and it marginally improved the predictive factor for M1 stage (HR = 7.59, 95% CI 2.30-25.07, P = .001) and distal tumors (HR = 5.04, 95% CI 1.88-13.49, P = .001).

Conclusions

Nodal invasion, metastatic disease, distal tumor site, low resection margins and perineural invasion were associated with disease recurrence. Pre-treatment methylated ctDNA measurement can improve the predictive value for recurrence in a subset of patients, particularly those with perineural involvement.

Registration

Australian and New Zealand Clinical Trials Registry #12611000318987.

Effectiveness and safety of intraoperative intraperitoneal 5-Fu drug implantation in patients with colorectal cancer: a retrospective cohort study

PURPOSE

The purpose of this clinical study was to evaluate the efficacy and safety of intraoperative chemotherapy (IOC) with intraoperative intraperitoneal implantation of 5-fluorouracil (5-FU) in colorectal cancer (CRC) patients.

METHODS

In this study, 165 patients who underwent colorectal radical surgery were selected, of whom 111 in the experimental group received surgical treatment with an intraperitoneal 5-fluorouracil (5-FU) implantation. Fifty-four patients who did not undergo intraperitoneal implantation of 5-FU were matched to compare the progression-free survival (PFS) and overall survival (OS) with the former.

RESULTS

We also studied the differences in the changes of different biochemical indicators between the two groups before and after surgery, and there were significant differences in leukocytes, neutrophils, and lymphocytes before and after (P < 0.05), while for sodium ions, potassium ions, platelets, alanine transaminase, aspartate transaminase, creatinine, urea, and albumin, there were no significant differences. This may be related to the intraperitoneal chemotherapy implant entering the blood circulation. For 5-year OS, there were 85/111 (76.58%) in the 5-FU group (P = 0.013) and 35/54 (64.81%) in the control group; for 5-year PFS, there were 84/111 (75.68%) in the 5-FU group and 29/54 (53.70%) in the control group (P = 0.02). All the experimental groups were better than the control group with a significant difference in the experimental results.

CONCLUSION

For CRC surgery patients, intraperitoneal implantation of slow-release 5-FU drugs, which is a safe and simple procedure, can improve the prognosis of the patients.

CLINICAL TRIAL REGISTRATION

No clinical trials were performed in the study.

Incidence of adhesive small bowel obstruction after surgery for colorectal cancer in Sweden 2007-2016

AIM

Population-based data on incidence and risk factors of adhesive small bowel obstruction (SBO) are limited. The aims of this study were to assess the risk of SBO and SBO surgery after bowel resection for colorectal cancer (CRC) and to assess whether this risk is modified by minimally invasive surgery (MIS) and radiotherapy in a retrospective national study.

METHODS

CRCBaSe, a nationwide register linkage originating from the Swedish Colorectal Cancer Register, was used to identify Stage I-III CRC patients who underwent resection in 2007-2016, with follow-up throughout 2017. Matched CRC-free comparators (1:6) were included as a reference of SBO and SBO surgery incidence. The association between MIS and preoperative radiotherapy and the incidence rate of SBO was evaluated in adjusted multivariable Cox regression models.

RESULTS

Among 33 632 CRC patients and 198 649 comparators, the 5-year cumulative incidence of SBO and SBO surgery was 7.6% and 2.2% among patients and 0.6% and 0.2% among comparators, with death as a competing risk. In all patients, MIS was associated with a reduced incidence of SBO (hazard ratio [HR] 0.7, 95% CI 0.6-0.8) and SBO surgery (HR 0.5, 95% CI 0.3-0.7). In rectal cancer patients, radiotherapy was associated with an increased incidence of SBO (HR 1.6, 95% CI 1.4-1.8) and SBO surgery (HR 1.7, 95% CI 1.3-2.3).

DISCUSSION

Colorectal cancer surgery is associated with a marked increase in risk of SBO, compared with the general population. The incidence is further increased if open surgery or radiotherapy is performed.

Metachronous colorectal cancer metastasis: Who, what, when and what to do about it

Metachronous colorectal cancer (CRC) metastasis occurs due to micrometastatic disease, in up to 23% of patients who have undergone curative-intent treatment. Metachronous metastasis tends to occur within 2 years of initial treatment. Diagnosis relies on posttreatment surveillance strategies. Care for patients with metachronous CRC metastasis is complex and requires careful multidisciplinary consideration. Those with isolated and technically resectable diseases are recommended to undergo metastasectomy with adjunct chemotherapy, however, survival, even after curative-intent resection, is poor.

Downregulation of osteoprotegerin in colorectal cancer cells promotes liver metastasis via activating tumor-associated macrophage

Osteoprotegerin (OPG) is a secreted cytokine that functions as a decoy receptor for receptor activator of nuclear factor kappa-B (RANK) ligand (RANKL). Anti-RANKL treatment for bone metastasis has been widely accepted for solid tumors. However, the mechanism of OPG-RANKL-RANK signaling in systemic colorectal cancer (CRC) metastasis remains unclear. In this study, we investigated the relevance and function of OPG expression in CRC liver metastasis. First, we performed in silico analysis using The Cancer Genome Atlas public database and found that lower OPG expression in CRC was associated with poor overall survival. Immunohistochemistry analyses using resected specimen from patients with CRC in our institute confirmed the result. Patient-matched primary CRC and liver metastases showed a significant downregulation of OPG expression in metastatic lesions. In CRC cell lines, OPG expression did not suppress cell proliferation and migration. However, OPG expression inhibited macrophage migration by suppressing the RANKL-RANK pathway. Moreover, in vivo mouse liver metastasis models showed that OPG expression in CRC cells suppressed liver metastases. In addition, treatment with an anti-RANKL neutralizing antibody also suppressed liver metastases. These results showed that downregulation of OPG expression in CRC cells promotes liver metastasis by activating tumor-associated macrophage, which can become a candidate for targeted therapy with anti-RANKL neutralizing antibody for CRC liver metastasis.

Extended Right-Sided Colon Resection Does Not Reduce the Risk of Colon Cancer Local-Regional Recurrence: Nationwide Population-Based Study From Danish Colorectal Cancer Group Database

BACKGROUND

It is controversial whether extensive resection of right-sided colon cancer confers oncological benefits.

OBJECTIVE

The aim of this study was to evaluate short- and long-term outcomes of extended surgical removal of the mesocolon compared to the conventional approach.

DESIGN

This was a retrospective population-based study.

SETTING

Study is based on a prospectively maintained Danish Colorectal Cancer Group database.

MAIN OUTCOME MEASURES

Primary outcome measures included local-regional recurrence in patients who underwent curative resection for right-sided colon cancer and 30-day postoperative complications. Distant metastasis, unplanned intraoperative adverse events, and 30- and 90-day postoperative mortality were also investigated. Patients who had palliative or compromised resection, emergency surgery, or neoadjuvant chemotherapy were excluded.

RESULTS

Of the 12,855 patients with resection of right-sided colon cancer retrieved, 1151 underwent extended right hemicolectomy. Patients who had extended right hemicolectomy were younger males with lower ASA scores, were operated on by colorectal surgeons using a laparoscopic approach, and had a significantly higher number of harvested lymph nodes. The rate of local-regional recurrence was 1.1% (136/12,855), with no difference between conventional right hemicolectomy and extended right hemicolectomy (OR, 1.7; 95% CI, 0.63-2.18). Postoperative medical complications were significantly higher in extended right hemicolectomy even after adjusting for age, comorbidity, access to the abdomen, and other covariates (OR, 1.26; 95% CI, 1.01-1.58). No significant difference was noticed between conventional right hemicolectomy and extended right hemicolectomy in the rates of distant metastasis, unplanned intraoperative adverse events, and mortality.

LIMITATIONS

Because it is a register-based study, underreporting cannot be excluded. Extended right hemicolectomy, as defined in this study, does not reflect the extent of lymphatic dissection performed during the surgery.

CONCLUSIONS

This large population-based register study showed no difference in local-regional recurrence of right-sided colon cancer between conventional and extended right hemicolectomy with mesenteric resection and ligation of the middle colic vessels. Extended resection was associated with higher rates of postoperative complications. See Video Abstract at http://links.lww.com/DCR/B907 .

LA RESECCIN AMPLIADA DEL COLON DERECHO NO REDUCE EL RIESGO DE RECURRENCIA LOCALREGIONAL DEL CNCER DE COLON ESTUDIO POBLACIONAL A NIVEL NACIONAL DE LA BASE DE DATOS DEL GRUPO DANS DE CNCER COLORRECTAL

ANTECEDENTES:Es aun un tema controversial si la resección ampliada del cáncer de colon del lado derecho confiere beneficios oncológicos.OBJETIVOS:El objetivo de este estudio fue examinar los resultados a corto y largo plazo de la resección quirúrgica ampliada del mesocolon en comparación con el enfoque convencional.DISEÑO:Este fue un estudio poblacional de tipo retrospectivo basado en una base de datos del Grupo Danés de Cáncer Colorrectal mantenida de manera prospectiva.AJUSTES:La medida de resultado primaria fue la recurrencia local-regional en pacientes sometidos a resección curativa por cáncer de colon del lado derecho y las medidas de resultado secundarias fueron las complicaciones posoperatorias a los 30 días. También fueron investigadas las metástasis a distancia, los eventos adversos intraoperatorios no planificados y la mortalidad posoperatoria a los 30 y 90 días. Se excluyeron los pacientes sometidos a resección paliativa o comprometida, cirugía de urgencia y quimioterapia neoadyuvante.RESULTADOS:De los 12.855 pacientes recuperados y sometidos a resección de cáncer de colon del lado derecho, 1151 fueron sometidos a hemicolectomía derecha ampliada. Los pacientes sometidos a hemicolectomía derecha ampliada fueron varones más jóvenes con puntuaciones ASA más bajas, operados por cirujanos colorrectales, utilizando la vía laparoscópica, y tuvieron un número significativamente mayor de ganglios linfáticos extraídos. La tasa de recidiva local-regional fue del 1,1% (136 / 12.855) sin diferencia entre la hemicolectomía derecha convencional y la hemicolectomía derecha ampliada (OR 1,7 IC 95% 0,63-2,18). Las complicaciones médicas post operatorias fueron significativamente mayores en la hemicolectomía derecha ampliada incluso después del ajuste por edad, comorbilidad, acceso al abdomen y otras covariables (OR 1,26; IC 95% 1,01-1,58). No se observaron diferencias significativas entre la hemicolectomía derecha convencional y la hemicolectomía derecha ampliada con respecto a las tasas de metástasis a distancia, eventos adversos intraoperatorios no planificados y mortalidad.LIMITACIONES:Es un estudio basado en registros, por lo tanto, no se puede excluir la sub notificación. La hemicolectomía derecha ampliada como se define en este estudio no refleja la extensión de la disección linfática realizada durante la cirugía.CONCLUSIONES:Este gran estudio basado en el registro poblacional no mostró diferencias en la recurrencia local-regional del cáncer de colon del lado derecho entre la hemicolectomía derecha convencional y ampliada con resección mesentérica y ligadura de los vasos cólicos medios. La resección ampliada se asoció con tasas más altas de complicaciones posoperatorias. Consulte Video Resumen en http://links.lww.com/DCR/B907 . (Traducción-Dr. Osvaldo Gauto ).

Identifying Recurrences Among Non-Metastatic Colorectal Cancer Patients Using National Health Data Registries: Validation and Optimization of a Registry-Based Algorithm in a Modern Danish Cohort

Purpose

Colorectal cancer (CRC) recurrence is not routinely recorded in Danish health data registries. Here, we aimed to revalidate a registry-based algorithm to identify recurrences in a contemporary cohort and to investigate the accuracy of estimating the time to recurrence (TTR).

Patients and Methods

We ascertained data on 1129 patients operated for UICC TNM stage I-III CRC during 2012-2017 registered in the CRC biobank at the Department of Molecular Medicine, Aarhus University Hospital, Denmark. Individual-level data were linked with data from the Danish Colorectal Cancer Group database, Danish Cancer Registry, Danish National Registry of Patients, and Danish Pathology Registry. The algorithm identified recurrence based on diagnosis codes of local recurrence or metastases, the receipt of chemotherapy, or a pathological tissue assessment code of recurrence more than 180 days after CRC surgery. A subgroup was selected for validation of the algorithm using medical record reviews as a reference standard.

Results

We found a 3-year cumulative recurrence rate of 20% (95% CI: 17-22%). Manual medical record review identified 80 recurrences in the validation cohort of 522 patients. The algorithm detected recurrence with 94% sensitivity (75/80; 95% CI: 86-98%) and 98% specificity (431/442; 95% CI: 96-99%). The positive and negative predictive values of the algorithm were 87% (95% CI: 78-93%) and 99% (95% CI: 97-100%), respectively. The median difference in TTR (TTR_{Medical_chart}-TTR_algorithm) was -8 days (IQR: -21 to +3 days). Restricting the algorithm to chemotherapy codes from oncology departments increased the positive predictive value from 87% to 94% without changing the negative predictive value (99%).

Conclusion

The algorithm detected recurrence and TTR with high precision in this contemporary cohort. Restriction to chemotherapy codes from oncology departments using department classifications improves the algorithm. The algorithm is suitable for use in future observational studies.

The Anticancer Effects of the Pro-Apoptotic Benzofuran-Isatin Conjugate (5a) Are Associated With p53 Upregulation and Enhancement of Conventional Chemotherapeutic Drug Efficiency in Colorectal Cancer Cell Lines

The present study aimed to investigate in-depth a cytotoxic novel benzofuran-isatin conjugate (5a, 3-methyl-N'-(2-oxoindolin-3-ylidene)benzofuran-2-carbohydrazide) with promising potential anticancer activities in colorectal adenocarcinoma HT29 and metastatic colorectal cancer (CRC) SW620 cell lines. Thus, the primary cell events involved in tumorigenicity, tumor development, metastasis, and chemotherapy response were explored. Both CRC cell lines were exposed to different concentrations of Compound 5a and then subjected to real-time cell viability, migration, and invasion assays, colony formation and cytotoxicity assays, and flow cytometry for cell cycle analysis and apoptosis determination. Western blot and RT-qPCR were performed to assess the protein and transcript expression levels of epithelial-mesenchymal transition (EMT), cell cycle, and apoptosis markers. We showed that the Compound 5a treatment exhibited anticancer effects through inhibition of HT29 and SW620 cell viability, migration, and invasion, in a dose-dependent manner, which were associated with the upregulation of the tumor suppressor p53. Compound 5a also inhibited the colony formation ability of HT29 and SW620 cells and reversed EMT markers E-cadherin and N-cadherin expression. CRC cell exposure to Compound 5a resulted in a cell cycle arrest at the G1/G0 phase in HT29 cells and at the G2/M phase in SW620 cells, along with the downregulation of cyclin A1 expression, described to be involved in the S phase entry. Furthermore, Compound 5a-induced apoptosis was associated with the downregulation of the anti-apoptotic Bcl-xl marker, upregulation of pro-apoptotic Bax and cytochrome c markers, and increased mitochondrial outer membrane permeability, suggesting the involvement of mitochondria-dependent apoptosis pathway. In addition, the combination studies of Compound 5a with the main conventional chemotherapeutic drugs 5-fluorouracil, irinotecan, and oxaliplatin showed a more potent cytotoxic effect in both CRC cells than a single treatment. In conclusion, our findings described the interesting in vitro anticancer properties of Compound 5a, shown to have possible antitumor, antimetastatic, and pro-apoptotic activities, with the enhancement of the cytotoxic efficiency of conventional chemotherapeutic drugs. In vivo studies are requested to confirm the promising anticancer potential of Compound 5a for CRC therapy.

Disparities in post-operative surveillance testing for metastatic recurrence among colorectal cancer survivors

PURPOSE

Among colorectal cancer (CRC) survivors, treatment for metastatic recurrence is most effective when malignancies are detected early through surveillance with carcinoembryonic antigen (CEA) level test and computer tomography (CT) imaging. However, utilization of these tests is low, and many survivors fail to meet the recommended guidelines. This population-based study assesses individual- and neighborhood-level factors associated with receipt of CEA and CT surveillance testing.

METHODS

We used the Surveillance, Epidemiology and End Results (SEER)-Medicare data to identify Medicare beneficiaries diagnosed with CRC stages II-III between 2010 and 2013. We conducted multivariate logistic regression to estimate the effect of individual and neighborhood factors on receipt of CEA and CT tests within 18 months post-surgery.

RESULTS

Overall, 78% and 58% of CRC survivors received CEA and CT testing, respectively. We found significant within racial/ethnic differences in receipt of these surveillance tests. Medicare-Medicaid dual coverage was associated with 39% lower odds of receipt of CEA tests among non-Hispanic Whites, and Blacks with dual coverage had almost two times the odds of receiving CEA tests compared to Blacks without dual coverage.

CONCLUSIONS

Although this study did not find significant differences in receipt of initial CEA and CT surveillance testing across racial/ethnic groups, the assessment of the factors that measure access to care suggests differences in access to these procedures within racial/ethnic groups.

IMPLICATIONS FOR CANCER SURVIVORS

Our findings have implications for developing targeted interventions focused on promoting surveillance for the early detection of metastatic recurrence among colorectal cancer survivors and improve their health outcomes.

Exosomal miRNAs as a Promising Source of Biomarkers in Colorectal Cancer Progression

Colorectal cancer (CRC) is the third most common type of cancer worldwide amongst males and females. CRC treatment is multidisciplinary, often including surgery, chemotherapy, and radiotherapy. Early diagnosis of CRC can lead to treatment initiation at an earlier stage. Blood biomarkers are currently used to detect CRC, but because of their low sensitivity and specificity, they are considered inadequate diagnostic tools and are used mainly for following up patients for recurrence. It is necessary to detect novel, noninvasive, specific, and sensitive biomarkers for the screening and diagnosis of CRC at earlier stages. The tumor microenvironment (TME) has an essential role in tumorigenesis; for example, extracellular vesicles (EVs) such as exosomes can play a crucial role in communication between cancer cells and different components of TME, thereby inducing tumor progression. The importance of miRNAs that are sorted into exosomes has recently attracted scientists’ attention. Some unique sequences of miRNAs are favorably packaged into exosomes, and it has been illustrated that particular miRNAs can be directed into exosomes by special mechanisms that occur inside the cells. This review illustrates and discusses the sorted and transported exosomal miRNAs in the CRC microenvironment and their impact on CRC progression as well as their potential use as biomarkers.

Reevaluating the Evidence for Intensive Postoperative Extracolonic Surveillance for Nonmetastatic Colorectal Cancer

OBJECTIVES

The FACS, GILDA, and COLOFOL trials have cast doubt on the value of intensive extracolonic surveillance for resected nonmetastatic colorectal cancer and by extension metastasectomy. We reexamined this pessimistic interpretation. We evaluate an alternative explanation: insufficient power to detect a realistically sized survival benefit that may be clinically meaningful.

METHODS

A microsimulation model of postdiagnosis colorectal cancer was constructed assuming an empirically plausible efficacy for metastasectomy and thus surveillance. The model was used to predict the large-sample mortality reduction expected for each trial and the implied statistical power. A potential recurrence imbalance in the FACS trial was investigated. Goodness of fit between model predictions and trial results were evaluated. Downstream life expectancy was estimated and power calculations performed for future trials evaluating surveillance and metastasectomy.

RESULTS

For all 3 trials, the model predicted a mortality reduction of ≤5% and power of <10%. The FACS recurrence imbalance likely led to a large relative bias (>2.5) in the hazard ratio for overall survival favoring control. After adjustment, both COLOFOL and FACS results were consistent with model predictions (P>.5). A 2.6 (95% credible interval 0.5-5.1) and 3.6 (95% credible interval 0.8-7.0) month increase in life expectancy is predicted comparing intensive extracolonic surveillance-routine computed tomography scans and carcinoembryonic antigen assays-with 1 computed tomography scan at 12 months or no surveillance, respectively. An adequately sized surveillance trial is not feasible. A metastasectomy trial should randomize at least 200 to 300 patients.

CONCLUSIONS

Recent trial results do not warrant de novo skepticism of metastasectomy nor targeted extracolonic surveillance. Given the potential for clinically meaningful life-expectancy gain and significant uncertainty, a trial of metastasectomy is needed.

Comparing 5-Year Survival Rates Before and After Re-stratification of Stage I-III Right-Sided Colon Cancer Patients by Establishing the Presence/Absence of Occult Tumor Cells and Lymph Node Metastases in the Different Levels of Surgical Dissection

BACKGROUND

To establish the impact of re-stratification on the outcomes of patients (stage I-III right-sided colon cancer) based on the presence/absence of occult tumor cells (OTC) and/or metastatic lymph nodes in the different levels of surgical dissection.

METHODS

Consecutive patients were drawn from a multicenter prospective trial. After surgery, the surgical specimen was divided into the D1/D2 and D3 volumes before being further analyzed separately. All lymph nodes were examined with cytokeratin CAM 5.2 immunohistochemically. Lymph nodes containing metastases and OTC (micrometastases; isolated tumor cells) were identified. Re-stratification was as follows: RS1, stages I/II, no OTC in D1/D2 and D3 volumes; RS2, stages I/II, OTC in D1/D2 and/or D3; RS3, stage III, lymph node metastases in D1/D2, with/without OTC in D3; RS4, stage III, lymph node metastases in D3, with/without OTC in D3.

RESULTS

Eighty-seven patients (39 men, 68.4 + 9.9 years) were included. The standard stratified (SS) group contained the following: stages I/II (SS1) 57 patients; stage III (SS2) 30 patients. Re-stratified (RS) contained RS1 (38), RS2 (19), RS3 (24), and RS4 (6) patients. Lymph node ratio (OTC) RS2: 0.157 D1/D2; 0.035 D3 and 0.092 complete specimens. Lymph node ratio RS3: 0.113 D1/D2; complete specimen 0.056. Overall survival and disease-free survival were p = 0.875 and p = 0.049 for SS and p = 0.144 and p = 0.001 for RS groups, respectively.

CONCLUSION

This re-stratification identifies a patient group with poor prognosis (RS4). Removing this group from SS2 eliminates all the differences in survival between RS2 and RS3 groups. The level of dissection of the affected nodes may have an impact on survival.

CLINICAL TRIAL

"Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic Multi-Detector Computed Tomography (MDCT) Angiography" registered at http://clinicaltrials.gov/ct2/show/NCT01351714.

Clinical Significance of Lymph Node Dissection and Lymph Node Metastasis in Primary Appendiceal Tumor Patients After Curative Resection: a Retrospective Multicenter Cohort Study

PURPOSE

Due to its rarity and biological heterogeneity, guidelines for primary appendiceal tumor (PAT) are based on scarce evidence, resulting in no strong recommendations. The present study explored prognosis-related factors, including the timing of lymph node dissection (LND), in PAT patients after curative resection (CR) to determine the optimal surgical therapies.

METHODS

We retrospectively collected and analyzed data from 404 patients with PATs who underwent CR at 43 tertiary hospitals from 2000 to 2017. This manuscript is based on revised manuscript during review process. Please, change the bold characters to normal characters in the manuscript.

RESULTS

After propensity score matching, there were no marked differences in the recurrence-free survival (RFS) or overall survival (OS) between the primary and secondary LND groups (P = 0.993 and 0.728). A multivariate analysis showed that lymph node metastasis (LNM) was an independent factor for the RFS (hazard ratio [HR] 2.59; 95% confidence interval [CI] 1.09-6.13; P = 0.031) and OS (HR 4.70; 95% CI 1.40-15.76; P = 0.012). There were significant associations between the LNM rates and tumor depth (P < 0.0001) and the histological type (P = 0.006). There was no LNM in patients with low-grade appendiceal mucinous neoplasm (LAMN) or well-differentiated mucinous adenocarcinoma (G1) or patients with any Tis or T1 PATs.

CONCLUSIONS

LNM was an independent prognostic predictor in PATs after CR with LND. Tumor depth and histological type were not prognostic predictors but were LNM predictors. Secondary LND based on the pathological findings of resected specimens is considered an acceptable surgical management without a worse prognosis than primary LND, and it may be omitted in LAMN+G1 or in any Tis and T1 PATs.

Clinical added value of MRI to CT in patients scheduled for local therapy of colorectal liver metastases (CAMINO): study protocol for an international multicentre prospective diagnostic accuracy study

BACKGROUND

Abdominal computed tomography (CT) is the standard imaging method for patients with suspected colorectal liver metastases (CRLM) in the diagnostic workup for surgery or thermal ablation. Diffusion-weighted and gadoxetic-acid-enhanced magnetic resonance imaging (MRI) of the liver is increasingly used to improve the detection rate and characterization of liver lesions. MRI is superior in detection and characterization of CRLM as compared to CT. However, it is unknown how MRI actually impacts patient management. The primary aim of the CAMINO study is to evaluate whether MRI has sufficient clinical added value to be routinely added to CT in the staging of CRLM. The secondary objective is to identify subgroups who benefit the most from additional MRI.

METHODS

In this international multicentre prospective incremental diagnostic accuracy study, 298 patients with primary or recurrent CRLM scheduled for curative liver resection or thermal ablation based on CT staging will be enrolled from 17 centres across the Netherlands, Belgium, Norway, and Italy. All study participants will undergo CT and diffusion-weighted and gadoxetic-acid enhanced MRI prior to local therapy. The local multidisciplinary team will provide two local therapy plans: first, based on CT-staging and second, based on both CT and MRI. The primary outcome measure is the proportion of clinically significant CRLM (CS-CRLM) detected by MRI not visible on CT. CS-CRLM are defined as liver lesions leading to a change in local therapeutical management. If MRI detects new CRLM in segments which would have been resected in the original operative plan, these are not considered CS-CRLM. It is hypothesized that MRI will lead to the detection of CS-CRLM in ≥10% of patients which is considered the minimal clinically important difference. Furthermore, a prediction model will be developed using multivariable logistic regression modelling to evaluate the predictive value of patient, tumor and procedural variables on finding CS-CRLM on MRI.

DISCUSSION

The CAMINO study will clarify the clinical added value of MRI to CT in patients with CRLM scheduled for local therapy. This study will provide the evidence required for the implementation of additional MRI in the routine work-up of patients with primary and recurrent CRLM for local therapy.

TRIAL REGISTRATION

The CAMINO study was registered in the Netherlands National Trial Register under number NL8039 on September 20th 2019.

Large Metastatic Cardiac Tumor from Ascending Colon Cancer with Autopsy

A metastatic cardiac tumor from colon cancer is an exceedingly rare clinical feature associated with a poor prognosis without therapeutic intervention; however, such cases may be frequently encountered in clinical practice, especially among the elderly. We report a case of synchronous double cancer of the prostate and ascending colon with metastases to multiple organs, including a large cardiac tumor. A 71-year-old Japanese man had prostate cancer with neck and para-aortic metastasis. He visited our hospital with complaints of fatigue and a positive fecal occult blood test result. Colonoscopy findings revealed the presence of a tumor in the ascending colon, and contrast-enhanced CT revealed a tumor in the heart, which was possibly due to metastasis from the ascending colon. The patient received palliative care and declined anticancer treatment. He died due to respiratory failure 3 months after the first diagnosis but did not show critical arrhythmia until death. Autopsy revealed the presence of a large mass in the right ventricle with tumor embolism of the right coronary artery. The cardiac mass was pathologically consistent with metastasis from the colon. In case of colorectal cancer with cardiac metastasis involving poor prognosis or performance status, best supportive care without any therapeutic intervention could be the optimal treatment for the quality of the remaining time.

Follow-up of colorectal cancer and patterns of recurrence

Colorectal cancer is one of the commonest cancers detected as also amongst the most common causes of cancer death. Survival has improved due to better disease understanding and treatment; however, a substantial proportion of patients recur after curative intent therapy. In this article, we will discuss the imaging features of recurrent colorectal cancer and the role of the radiologist in its management.

Interactions of occult tumor spread and surgical technique on overall and disease-free survival in patients operated for stage I and II right-sided colon cancer

Purpose

To determine if “medial to lateral” (ML) dissection with devascularization first is superior to “lateral to medial” (LM) dissection regarding numbers of lymph node micro metastases (MM) and isolated tumor cells (ITC) as well as 5-year disease-free (5YDFS) and 5-year overall survival (5YOS) in stage I/II right-sided colon cancer.

Methods

Two datasets are used. ML group consists of consecutive stage I/II patients from a prospective trial. LM group is the original dataset from a previous publication. All harvested lymph nodes are examined with monoclonal antibody CAM 5.2 (immunohistochemically). Lymph node harvest and 5YOS/5YDFS were compared between ML/LM groups, stage I/II tumors and MM/ITC presence/absence.

Results

117 patients included ML:51, LM:66. MM/ITC positive in ML 37.3% (19/51), LM 31.8% (21/66) p = 0.54. The 5YDFS for patients in ML 70.6% and LM 69.7%, p = 0.99, 5YOS: 74.5% ML and 71.2% LM (p = 0.73). No difference in 5YDFS/5YOS between groups for Stage I/II tumors; however, LM group had an excess of early tumors (16) when compared to ML group, while lymph node harvest was significantly higher in ML group (p < 0.01) 15.1 vs 26.7. 5YDFS and 5YOS stratified by MM/ITC presence/absence was 67.5%/71.4%, p = 0.63, and 75.0%/71.4%, p = 0.72, respectively. Death due to recurrence in MM/ITC positive was significantly higher than MM/ITC negative (p = 0.012).

Conclusion

Surgical technique does not influence numbers of MM/ITC or 5YDFS/5YOS. Presence of MM/ITC does not affect 5YOS/5YDFS but can be a potential prognostic factor for death due to recurrence.

Clinical trial

Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic Multi-Detector Computed Tomography (MDCT) Angiography” registered at http://clinicaltrials.gov/ct2/show/NCT01351714 .

The oncologic safety of left colectomy with modified complete mesocolic excision for distal transverse colon cancer: Comparison with descending colon cancer

BACKGROUND

The optimal surgical approach for distal transverse colon cancer has not been well established. This study aimed to evaluate the oncologic safety of left colectomy with a modified complete mesocolic excision for distal transverse colon cancer as compared with descending colon cancer.

MATERIAL AND METHODS

This study involved 383 patients who underwent left colectomy with modified complete mesocolic excision for non-metastatic distal transverse and splenic flexure colon (transverse group, N = 110) and descending colon cancer (descending group, N = 237) from 3 institutions. Recurrence-free survival (RFS) and overall survival (OS) were compared between the two groups.

RESULTS

Baseline characteristics between the two groups were similar except for the length of the distal margin (transverse group = 11.0 cm vs descending group = 9.0 cm, p = 0.004). During a median follow-up of 47.0 months, RFS and OS were not different between the transverse and descending groups (5-year RFS: 82% vs 71%, p = 0.139; 5-year OS: 83% vs 79%, p = 0.416, respectively). In multivariable analysis, RFS and OS were not different between the two groups (transverse group vs. descending group: adjusted hazard ratio [aHR] = 1.557, 95% CI = 0.786-3.084, p = 0.204; aHR = 1.251, 95% CI = 0.530-2.952, p = 0.609).

CONCLUSION

The oncologic outcomes of left colectomy with a modified complete mesocolic excision of distal transverse colon cancer were comparable to those of descending colon cancer. Left colectomy with a modified complete mesocolic excision can be an acceptable surgical treatment for distal transverse colon cancer.

Treatment sequencing of metastatic colorectal cancer based on primary tumor location

Colorectal cancer is a heterogeneous disease with various clinical, molecular, and embryological differences related to the origin of the tumor from the right or left colon. Recent studies have demonstrated that tumor sidedness has both a prognostic and predictive value in metastatic colorectal cancer . Patients whose primary tumor originates from the left side of the colon and whose tumor's genome encodes wild-type RAS and BRAF should be offered cetuximab or panitumumab in the first-line treatment of metastatic disease or in subsequent lines. For tumors originating from the right side of the colon, anti-angiogenic treatment, particularly bevacizumab, is an option for this poor prognostic group until better options become available. Specifically, an aggressive initial approach with FOLFOXIRI plus bevacizumab is a treatment option in right-sided tumors under investigation. This report reviews the available data for the treatment of metastatic colorectal cancer according to the location of the primary tumor and proposes the optimal treatment sequencing strategy incorporating the site of origin of the tumor and molecular information into the decision-making process.

LIN28B induces a differentiation program through CDX2 in colon cancer

Most colorectal cancers (CRCs) are moderately differentiated or well differentiated, a status that is preserved even in metastatic tumors. However, the molecular mechanisms underlying CRC differentiation remain to be elucidated. Herein, we unravel a potentially novel posttranscriptional regulatory mechanism via a LIN28B/CDX2 signaling axis that plays a critical role in mediating CRC differentiation. Owing to a large number of mRNA targets, the mRNA-binding protein LIN28B has diverse functions in development, metabolism, tissue regeneration, and tumorigenesis. Our RNA-binding protein IP (RIP) assay revealed that LIN28B directly binds CDX2 mRNA, which is a pivotal homeobox transcription factor in normal intestinal epithelial cell identity and differentiation. Furthermore, LIN28B overexpression resulted in enhanced CDX2 expression to promote differentiation in subcutaneous xenograft tumors generated from CRC cells and metastatic tumor colonization through mesenchymal-epithelial transition in CRC liver metastasis mouse models. A ChIP sequence for CDX2 identified α-methylacyl-CoA racemase (AMACR) as a potentially novel transcriptional target of CDX2 in the context of LIN28B overexpression. We also found that AMACR enhanced intestinal alkaline phosphatase activity, which is known as a key component of intestinal differentiation, through the upregulation of butyric acid. Overall, we demonstrated that LIN28B promotes CRC differentiation through the CDX2/AMACR axis.

Exosomal microRNAs in colorectal cancer: Overcoming barriers of the metastatic cascade (Review)

The journey of cancer cells from a primary tumor to distant sites is a multi-step process that involves cellular reprogramming, the breaking or breaching of physical barriers and the preparation of a pre-metastatic niche for colonization. The loss of adhesion between cells, cytoskeletal remodeling, the reduction in size and change in cell shape, the destruction of the extracellular matrix, and the modification of the tumor microenvironment facilitate migration and invasion into surrounding tissues. The promotion of vascular leakiness enables intra- and extravasation, while angiogenesis and immune suppression help metastasizing cells become established in the new site. Tumor-derived exosomes have long been known to harbor microRNAs (miRNAs or miRs) that help prepare secondary sites for metastasis; however, their roles in the early and intermediate steps of the metastatic cascade are only beginning to be characterized. The present review article presents a summary and discussion of the miRNAs that form part of colorectal cancer (CRC)-derived exosomal cargoes and which play distinct roles in epithelial to mesenchymal plasticity and metastatic organotropism. First, an overview of epithelial-to-mesenchymal transition (EMT), metastatic organotropism, as well as exosome biogenesis, cargo sorting and uptake by recipient cells is presented. Lastly, the potential of these exosomal miRNAs as prognostic biomarkers for metastatic CRC, and the blocking of these as a possible therapeutic intervention is discussed.

Metastases in locally advanced rectal cancer undergoing curatively intended treatment

BACKGROUND

The main cause of mortality in locally advanced rectal cancer (LARC) is metastatic progression. The aim of the present study was to describe frequency, pattern and outcome of metastatic disease in a cohort of LARC patients after curative resection.

METHODS

This was a single-centre cohort study of 628 LARC cases after neoadjuvant chemoradiotherapy/radiotherapy (CRT/RT) and surgery. Data, including the first site of metastasis, was registered in an institutional database linked to the National Cancer Registry.

RESULTS

Metastases were diagnosed in 270 patients (43.0%) with liver and lungs as the first site in 113 and 96 cases, respectively. Involved resection margins, high tumour stage and poor response to CRT/RT were associated with metastasis development and inferior overall survival (OS). Metastasectomy was performed in 76 (67.3%) patients with liver metastases and 28 (29.2%) patients with lung metastases. Five-year OS was 89% in patients without metastases and 32% in metastatic cases. In patients selected for metastasectomy, 5-year OS was 69% and 53% for lung and liver metastases, respectively. Corresponding numbers without metastasectomy were 12% and 0%.

CONCLUSION

In this large LARC cohort undergoing curatively intended treatment, liver and lung metastases occurred at similar frequencies. Liver as the first metastatic site was associated with inferior long-term outcome, while selection for metastasectomy was associated with better OS, with more than half of the resected patients being alive five years after LARC surgery. Our results show that the presence of resectable metastatic disease at diagnosis should not exclude a curative therapeutic approach in LARC.

Prognostic importance of circumferential resection margin in the era of evolving surgical and multidisciplinary treatment of rectal cancer: A systematic review and meta-analysis

BACKGROUND

Circumferential resection margin is considered an important prognostic parameter after rectal cancer surgery, but its impact might have changed because of improved surgical quality and tailored multimodality treatment. The aim of this systematic review was to determine the prognostic importance of circumferential resection margin involvement based on the most recent literature.

METHODS

A systematic literature search of MEDLINE, Embase, and the Cochrane Library was performed for studies published between January 2006 and May 2019. Studies were included if 3- or 5-year oncological outcomes were reported depending on circumferential resection margin status. Outcome parameters were local recurrence, overall survival, disease-free survival, and distant metastasis rate. The Newcastle Ottawa Scale and Jadad score were used for quality assessment of the studies. Meta-analysis was performed using a random effects model and reported as a pooled odds ratio or hazard ratio with 95% confidence interval.

RESULTS

Seventy-five studies were included, comprising a total of 85,048 rectal cancer patients. Significant associations between circumferential resection margin involvement and all long-term outcome parameters were uniformly found, with varying odds ratios and hazard ratios depending on circumferential resection margin definition (<1 mm, ≤1 mm, otherwise), neoadjuvant treatment, study period, and geographical origin of the studies.

CONCLUSION

Circumferential resection margin involvement has remained an independent, poor prognostic factor for local recurrence and survival in most recent literature, indicating that circumferential resection margin status can still be used as a short-term surrogate endpoint.

18F FDG PET/MRI with hepatocyte-specific contrast agent for M staging of rectal cancer: a primary economic evaluation

Purpose

Rectal cancer is one of the most frequent causes of cancer-related morbidity and mortality in the world. Correct identification of the TNM state in primary staging of rectal cancer has critical implications on patient management. Initial evaluations revealed a high sensitivity and specificity for whole-body PET/MRI in the detection of metastases allowing for metastasis-directed therapy regimens. Nevertheless, its cost-effectiveness compared with that of standard-of-care imaging (SCI) using pelvic MRI + chest and abdominopelvic CT is yet to be investigated. Therefore, the aim of this study was to analyze the cost-effectiveness of whole-body ¹⁸F FDG PET/MRI as an alternative imaging method to standard diagnostic workup for initial staging of rectal cancer.

Methods

For estimation of quality-adjusted life years (QALYs) and lifetime costs of diagnostic modalities, a decision model including whole-body ¹⁸F FDG PET/MRI with a hepatocyte-specific contrast agent and pelvic MRI + chest and abdominopelvic CT was created based on Markov simulations. For obtaining model input parameters, review of recent literature was performed. Willingness to pay (WTP) was set to $100,000/QALY. Deterministic sensitivity analysis of diagnostic parameters and costs was applied, and probabilistic sensitivity was determined using Monte Carlo modeling.

Results

In the base-case scenario, the strategy whole-body ¹⁸F FDG PET/MRI resulted in total costs of $52,186 whereas total costs of SCI were at $51,672. Whole-body ¹⁸F FDG PET/MRI resulted in an expected effectiveness of 3.542 QALYs versus 3.535 QALYs for SCI. This resulted in an incremental cost-effectiveness ratio of $70,291 per QALY for PET/MRI. Thus, from an economic point of view, whole-body ¹⁸F FDG PET/MRI was identified as an adequate diagnostic alternative to SCI with high robustness of results to variation of input parameters.

Conclusion

Based on the results of the analysis, use of whole-body ¹⁸F FDG PET/MRI was identified as a feasible diagnostic strategy for initial staging of rectal cancer from a cost-effectiveness perspective.

The landscape of small cell lung cancer metastases: Organ specificity and timing

BACKGROUND

Early metastasis is a hallmark of small cell lung cancer (SCLC). However, the mechanisms and resulting patterns of SCLC dissemination are unclear. Our aim was thus to investigate the organ specificity and timing of blood-borne metastases in a comprehensive large cohort of SCLC patients.

METHODS

In this retrospective non-interventional cross-sectional study of 1009 Caucasian SCLC patients, we investigated the correlation between the distinct locations of the primary tumor and metastatic sites.

RESULTS

The onset of bone (p < 0.001), brain (p < 0.001), and pericardial (p = 0.02) metastases were late events, whereas adrenal gland (p = 0.005) and liver (p < 0.001) metastases occurred earlier. No significant difference was found in the distribution of early versus late metastases when comparing central and peripheral primary tumors. Patients with bone metastases had a higher than expected likelihood of having liver metastases, while brain metastases tended to appear together with adrenal gland metastases. Pleural and both lung and pericardial metastases also tended to co-metastasize together more frequently than expected if metastatic events occurred independently. Notably, patients with central primary tumors had decreased median overall survival (OS) compared to those with peripheral tumors, although this tendency does not appear to be significant (p = 0.072).

CONCLUSION

Our results are suggestive for particular site- and sequence-specific metastasis patterns in human SCLC. SCLC bone metastases tend to appear together with liver metastases, while brain metastases occur together with adrenal gland metastases. Better understanding of metastasis distribution patterns might help to improve the diagnosis and therapeutic decision-making in SCLC patients.

Repeated centralized multidisciplinary team assessment of resectability, clinical behavior, and outcomes in 1086 Finnish metastatic colorectal cancer patients (RAXO): A nationwide prospective intervention study

Background

Resection of colorectal cancer (CRC) metastases provides good survival but is probably underused in real-world practice.

Methods

A prospective Finnish nationwide study enrolled treatable metastatic CRC patients. The intervention was the assessment of resectability upfront and twice during first-line therapy by the multidisciplinary team (MDT) at Helsinki tertiary referral centre. The primary outcome was resection rates and survival.

Findings

In 2012–2018, 1086 patients were included. Median follow-up was 58 months. Multiple metastatic sites were present in 500 (46%) patients at baseline and in 820 (76%) during disease trajectory. In MDT assessments, 447 (41%) were classified as resectable, 310 (29%) upfront and 137 (18%) after conversion therapy. Six-hundred and ninety curative intent resections or local ablative therapies (LAT) were performed in 399 patients (89% of 447 resectable). Multiple metastasectomies for multisite or later developing metastases were performed in 148 (37%) patients. Overall, 414 liver, 112 lung, 57 peritoneal, and 107 other metastasectomies were performed. Median OS was 80·4 months in R0/1-resected (HR 0·15; CI_95% 0·12–0·19), 39·1 months in R2-resected/LAT (0·39; 0·29–0·53) patients, and 20·8 months in patients treated with “systemic therapy alone” (reference), with 5-year OS rates of 66%, 40%, and 6%, respectively.

Interpretation

Repeated centralized MDT assessment in real-world metastatic CRC patients generates high resectability (41%) and resection rates (37%) with impressive survival, even when multisite metastases are present or develop later.

Funding

The funders had no role in the study design, analysis, and interpretation of the data or writing of this report.

Hazard function analysis of metastatic recurrence after colorectal cancer surgery-A nationwide retrospective study

BACKGROUND AND OBJECTIVES

An optimal postoperative surveillance protocol for colorectal cancer (CRC) is dependent on understanding the time line of recurrence. By hazard function analysis, this study aimed at evaluating the time of occurrence of metastasis.

METHODS

A total of 21,671 Stage I-III colon cancer patients were retrospectively included from the Japanese study group for postoperative follow-up of colorectal cancer database.

RESULTS

The 5-year incidence by metastasized organ was 6.3% for liver (right:left = 5.5%:7.0%, p = .0067), 6.0% for lung (right:left:rectum = 3.7%:4.4%:8.8%, p = 7.05E-45), and 2.0% for peritoneal (right:left:rectum = 3.1%:2.0%:1.2%, p = 1.29E-12). The peak of liver metastasis hazard rate (HR) (0.67 years) was earlier and higher than those of other metastases. The peak HR tended to be delayed in early stage CRCs (0.91, 0.76, and 0.52 years; for Stages I, II, and III, respectively). When analyzed as per the primary tumor location (right-sided, left-sided, and rectum), the peak HR for lung metastasis was twice as high for rectal cancer than for colon cancer, and peritoneal metastasis had a high HR in right-sided colon cancers.

CONCLUSION

The time course for the risk of recurrence in various metastatic organs based on the primary tumor site was clearly visualized in this study. This will aid in individualizing postoperative surveillance schedules.

Metabolic syndrome is a predictor of all site and liver-specific recurrence following primary resection of colorectal cancer: Prospective cohort study of 1006 patients

INTRODUCTION

Large epidemiological studies have demonstrated the link between metabolic syndrome and cancer development, including colorectal cancer. However, the influence of metabolic syndrome on disease progression is less well studied, particularly in the post-surgical setting. This study investigates the effect of metabolic syndrome on colorectal cancer recurrence (all-site and liver-specific) after curative surgery for Stage I-III disease.

MATERIALS AND METHODS

Consecutive patients who underwent curative resection for Stage I-III colorectal cancer in a single UK centre were prospectively recruited. Disease-free and overall survival with metabolic syndrome as a factor, were determined using the Kaplan-Meier technique. Hazard ratios for all-site and liver-specific recurrence were determined using univariable and multivariable Cox-regression models.

RESULTS

1006 patients were recruited and followed up for a median of 50 months (IQR 30-67). 177 patients (17.6%) met the criteria for metabolic syndrome. 245 patients (25.4%) developed recurrence, 161 (16.0%) of these had liver recurrence. The presence of metabolic syndrome was associated with a reduction in disease-free survival from 69 to 58 months (p < 0.001) and overall survival from 74 to 61 months (p < 0.001). Metabolic syndrome was an independent predictor of all-site (HR 1.76; p < 0.001) and liver-specific (HR 1.74; p = 0.01) recurrence.

CONCLUSION

Metabolic syndrome is a predictor of all-site and liver-specific recurrence after primary resection of stage I-III colorectal cancer.

Disease recurrence after colorectal cancer surgery in the modern era: a population-based study

PURPOSE

This population-based study determined the cumulative incidence (CI) of local, regional, and distant recurrences, examined metastatic patterns, and identified risk factors for recurrence after curative treatment for CRC.

METHODS

All patients undergoing resection for pathological stage I-III CRC between January 2015 and July 2015 and registered in the Netherlands Cancer Registry were selected (N = 5412). Additional patient record review and data collection on recurrences was conducted by trained administrators in 2019. Three-year CI of recurrence was calculated according to sublocation (right-sided: RCC, left-sided: LCC and rectal cancer: RC) and stage. Cox competing risk regression analyses were used to identify risk factors for recurrence.

RESULTS

The 3-year CI of recurrence for stage I, II, and III RCC and LCC was 0.03 vs. 0.03, 0.12 vs. 0.16, and 0.31 vs. 0.24, respectively. The 3-year CI of recurrence for stage I, II, and III RC was 0.08, 0.24, and 0.38. Distant metastases were found in 14, 12, and 16% of patients with RCC, LCC, and RC. Multiple site metastases were found often in patients with RCC, LCC, and RC (42 vs. 32 vs. 28%). Risk factors for recurrence in stage I-II CRC were age 65-74 years, pT4 tumor size, and poor tumor differentiation whereas in stage III CRC, these were ASA III, pT4 tumor size, N2, and poor tumor differentiation.

CONCLUSIONS

Recurrence rates in recently treated patients with CRC were lower than reported in the literature and the metastatic pattern and recurrence risks varied between anatomical sublocations.

Dietary fats suppress the peritoneal seeding of colorectal cancer cells through the TLR4/Cxcl10 axis in adipose tissue macrophages

Peritoneal carcinomatosis (PC) of colorectal cancer (CRC) is a terminal phase of malignancy with no effective strategies for the prevention of this condition. Here we established PC models in mice by intraperitoneal engraftment of CRC cells and revealed an unexpected role for a high-fat diet (HFD) in preventing metastatic seeding in the visceral fat. Mechanistically, the HFD stimulated the activation of adipose tissue macrophages (ATMs) toward an M1-like phenotype and enhanced ATM tumor phagocytosis in a TLR4-dependent manner. Furthermore, the TLR4–Cxcl10 axis in ATMs promoted T cell recruitment, and M1-like macrophages stimulated T cell activation in tumor-seeded fats. The inhibitory effect of the HFD on tumor seeding was abolished with the ablation of macrophages, inactivation of T cells, or blockade of the TLR4–Cxcl10 axis in macrophages. Finally, we showed that a HFD and conventional chemotherapeutic agents (oxaliplatin or 5-fluorouracil) synergistically improved the survival of tumor-seeded mice. Collectively, our findings demonstrate that peritoneal seeding of CRC can be suppressed by short-term treatment with a HFD in the early phase, providing a novel concept for the management of these patients in the clinic.

Relative effects of direct spread, lymph node metastasis and venous invasion in relation to blood borne distant metastasis present at the time of resection of colorectal cancer

Conventionally, lymphatic spread is regarded as the principal mechanism by which haematogenous metastasis occurs in colorectal cancer. The aim of this cross sectional study was to determine the relative strengths of direct tumour spread, the presence of lymph node metastasis and histologically demonstrated venous invasion as drivers of haematogenous metastasis diagnosed at the time of resection of colorectal cancer. The data were drawn from a hospital database of consecutive bowel cancer resections between 1995 and 2017 inclusive. The presence of haematogenous metastasis was determined at the time of surgery by imaging or other investigations or operative findings. Where possible, histological confirmation was obtained. Specimen dissection and reporting followed a standardised procedure. Tumour staging was according to the 7th edition of the UICC/AJCC pTNM system. Analysis was by multivariable logistic regression. After exclusions 3133 patients remained, among whom 380 (12.1%) had one or more haematogenous metastases. In bivariate analyses, the frequency of haematogenous metastasis was directly associated with increasing T status (p<0.001), increasing N status (p<0.001) and increasing extent of venous invasion (p<0.001) and with some other patient and tumour features. In a multivariable model, after adjustment for other features, associations with the occurrence of haematogenous metastasis were as follows: T3 odds ratio (OR) 4.41 (95% confidence interval 2.40-8.10), p<0.001; T4a OR 6.29 (3.27-12.10), p<0.001; T4b OR 5.50 (2.71-11.15), p<0.001; N1 OR 3.39 (2.47-4.64), p<0.001; N2 OR 4.59 (3.21-6.54), p<0.001; mural venous invasion OR 2.18 (1.14-4.16), p=0.018; extramural venous invasion OR 2.91 (2.21-3.83), p<0.001. Only three other features had significant, though weak effects in the model. These results led to the conclusion that venous invasion, demonstrated histologically and also inferred independently by the extent of direct tumour spread, made a greater contribution to the occurrence of haematogenous metastasis than did spread through lymphatics. Our approach and findings may have implications for other cancer sites apart from colorectal cancer.

Colorectal Cancer Metastases to Brain or Bone and the Relationship to Primary Tumor Location: a Population-Based Study

BACKGROUND

The association of primary tumor location with incidence and prognosis of brain or bone metastasis in metastatic colorectal cancer (mCRC) patients remains unclear. We dissect this association across a large population.

METHODS

A total of 202,401 CRC patients from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015 were included. For brain metastasis, 9478 cases without brain metastasis information were excluded, leaving 192,923 CRC for incidence analysis and multivariable logistic/Cox regression analyses. Similarly, 193,013 CRC were eligible for bone metastasis analyses.

RESULTS

The incidence of brain or bone metastasis at initial diagnosis was 1.38% and 6.12% in mCRC cohort, respectively. Median survival of CRC patients with brain or bone metastasis was 4 and 5 months, respectively. Primary tumor location is not associated with the incidence of brain metastasis but with bone metastasis. For bone metastasis, right-sided colon cancer (RCC) patients exhibited the lowest incidence, whereas rectal cancer (RC) patients had the highest. For both brain and bone metastases, RCC patients always had the shortest median survival, whereas RC patients had the longest. The common risk factors for brain or bone metastasis were grade III and multi-extracerebral or ectosteal metastases. The favorable prognostic factors for brain or bone metastasis were being female, married, insured, and RC. RCC is an unfavorable prognostic factor.

CONCLUSIONS

Primary tumor location impacts incidence proportions of bone metastasis and survival of both brain and bone mCRC patients. Primary tumor location should be taken into consideration in clinical practice and prognostic assessment.

Perioperative COX2 and β-adrenergic blockade improves biomarkers of tumor metastasis, immunity, and inflammation in colorectal cancer: A randomized controlled trial

BACKGROUND

Preclinical studies have implicated excess release of catecholamines and prostaglandins in the mediation of prometastatic processes during surgical treatment of cancer. In this study, we tested the combined perioperative blockade of these pathways in patients with colorectal cancer (CRC).

METHODS

In a randomized, double-blind, placebo-controlled biomarker trial involving 34 patients, the β-blocker propranolol and the COX2-inhibitor etodolac were administered for 20 perioperative days, starting 5 days before surgery. Excised tumors were subjected to whole genome messenger RNA profiling and transcriptional control pathway analyses.

RESULTS

Drugs were well-tolerated, with minor complications in both the treatment group and the placebo group. Treatment resulted in a significant improvement (P < .05) of tumor molecular markers of malignant and metastatic potential, including 1) reduced epithelial-to-mesenchymal transition, 2) reduced tumor infiltrating CD14⁺ monocytes and CD19⁺ B cells, and 3) increased tumor infiltrating CD56⁺ natural killer cells. Transcriptional activity analyses indicated a favorable drug impact on 12 of 19 a priori hypothesized CRC-related transcription factors, including the GATA, STAT, and EGR families as well as the CREB family that mediates the gene regulatory impact of β-adrenergic- and prostaglandin-signaling. Alterations observed in these transcriptional activities were previously associated with improved long-term clinical outcomes. Three-year recurrence rates were assessed for long-term safety analyses. An intent-to-treat analysis revealed that recurrence rates were 12.5% (2/16) in the treatment group and 33.3% (6/18) in the placebo group (P = .239), and in protocol-compliant patients, recurrence rates were 0% (0/11) in the treatment group and 29.4% (5/17) in the placebo group (P = .054).

CONCLUSIONS

The favorable biomarker impacts and clinical outcomes provide a rationale for future randomized placebo-controlled trials in larger samples to assess the effects of perioperative propranolol/etodolac treatment on oncological clinical outcomes.

Prognosis and risk factors for the development of pulmonary metastases after preoperative chemoradiotherapy and radical resection in patients with locally advanced rectal cancer

Background

Although preoperative chemoradiotherapy (CRT) followed by total mesorectal excision (TME) is currently considered effective for treating locally advanced rectal cancer (LARC), a proportion of patients develop postoperative pulmonary metastases. The current study aimed to assess the prognostic characteristics and risk factors for the development of rectal cancer pulmonary metastases after CRT and radical resection.

Methods

We retrospectively analyzed data collected on 544 consecutive patients who were diagnosed with LARC and underwent preoperative CRT followed by tumor radical resection between December 2003 and June 2014. Overall survival (OS), disease-free survival (DFS), and pulmonary metastasis rates were calculated and compared among the subgroups, and risk factors for pulmonary metastases were identified by Cox models.

Results

A total of 61 (11.2%) patients developed pulmonary metastases postoperatively, 45 of whom (73.8%) developed the condition in the first 24 months. The 1-, 2-, and 3-year pulmonary metastasis rates were 6.7%, 10.4%, and 11.7%, respectively. Compared with the disease-free group, the pulmonary metastases group had a significantly lower proportion of downstaging and pathological complete regression (pCR) rate and a significantly higher proportion of low rectum tumor. In multivariate analysis, a distance of the tumor ≤5 cm from the anal verge [hazard ratio (HR), 1.394; 95% confidence interval (CI), 1.211-3.736; P=0.003] was identified as an independent negative predictor of the 3-year pulmonary metastasis rate, and N0 stage (HR, 0.490; 95% CI, 0.261-0.919; P=0.026) and TNM downstaging (HR, 0.514; 95% CI, 0.265-0.997; P=0.049) were identified as independent positive predictors of the 3-year pulmonary metastasis rate.

Conclusions

Pulmonary metastases warranted a more intensive follow-up in patients with low rectal cancer, lymph node metastases and poor response after preoperative CRT and radical tumor resection.

Impact of RAS/RAF mutations on clinical and prognostic outcomes in metastatic colorectal cancer

Introduction: Early-activated RAS/RAF mutation status is a key molecular finding in colorectal cancer (CRC), while these mutations have been proposed as predictive and prognostic biomarkers. The present study has been designed as a longitudinal study to evaluate and summarize the different genotypes of metastatic CRC (mCRC), and assessing any association with the disease prognosis and clinicopathological characteristics. This study was performed in two main referral hospitals of Tabriz University of Medical Sciences, over three years (2016-2018).

Methods: Mutations were detected by Idylla tests of KRAS/NRAS/BRAF among a total of 173 mCRCs, using surgically-resected specimens or biopsied samples. To evaluate the factors associated with overall survival (OS) and prognosis, the Cox proportional hazards model was used in two steps to estimate the outcome measures (hazard ratio, or HR) with a 95% confidence interval (CI).

Results: The nominal 1 to 5-year OS rates were 78%, 65%, 55%, 46%, and 42%, respectively. KRAS mutations in codon 12 was an independent significant prognostic factor, as the patients with codon 12 mutations had a significantly lower OS (P Log-rank=0.049) and a higher hazard of mortality (HR=2.30; 95% CI: 0.95-5.58; P =0.066). Also, the mCRC patients with liver metastasis (HR=2.49; 95% CI: 1.49-12.52; P =0.002) and tumors of the distal colon (HR=3.36; 95% CI: 1.07-10.49; P =0.037) had a significantly worse prognosis.

Conclusion: KRAS mutation in codon 12 was an independent significant poor prognostic factor, and patients with liver metastasis had a significantly worse prognosis. Routinely performing specific oncogenic tests may help improve the patients’ prognosis and life expectancy.

Time of Metastasis and Outcome in Colorectal Cancer

OBJECTIVE

The aim of this study was to evaluate outcomes of metastases at various time intervals after colorectal cancer (CRC) diagnosis.

BACKGROUND

Earlier studies have indicated a short time interval between CRC diagnosis and distant metastases to be associated with poor prognosis. The majority of studies assessed outcome from CRC diagnosis or metastasis resection rather than from metastasis diagnosis and might be subject to immortal time bias.

METHODS

Patients in the population-based DACHS study were stratified: metastases at/within 1 month (immediate), 2 to 6 months (early), 7 to 12 months (intermediate), and >12 months (late) after CRC diagnosis. The primary endpoint was overall survival (OS) from metastasis diagnosis. Cox proportional hazards regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CI). HRs were adjusted for important confounders and immortal time.

RESULTS

A total of 1027 patients were included. T4 (P < 0.0001) and node-positive tumors (P < 0.0001) were more frequent in the immediate group. Lung metastases (P < 0.0001) and single-site metastases (P < 0.0001) were more prevalent in the late group. In multivariable analysis, immediate metastases were not associated with poor OS compared to metastases at later time points (late vs immediate: HR 1.21; 95% CI, 0.98-1.48). Subgroup analyses revealed poor OS of late versus immediate metastases for females (1.45; 1.08-1.96), proximal colon cancer (1.54; 1.09-2.16), and N0 (1.46; 1.00-2.12) or N1 disease (1.88; 1.17-3.05).

CONCLUSIONS

Immediate or early metastases are not associated with unfavorable outcome compared to late metastases. These findings challenge the current notion of poor outcome for CRC with immediate or early metastases.

Molecular subtyping improves prognostication of Stage 2 colorectal cancer

Background

Post-surgical staging is the mainstay of prognostic stratification for colorectal cancer (CRC). Here, we compare TNM staging to consensus molecular subtyping (CMS) and assess the value of subtyping in addition to stratification by TNM.

Methods

Three hundred and eight treatment-naïve colorectal tumours were accessed from our institutional tissue bank. CMS typing was carried out using tumour gene-expression data. Post-surgical TNM-staging and CMS were analysed with respect to clinicopathologic variables and patient outcome.

Results

CMS alone was not associated with survival, while TNM stage significantly explained mortality. Addition of CMS to TNM-stratified tumours showed a prognostic effect in stage 2 tumours; CMS3 tumours had a significantly lower overall survival (P = 0.006). Stage 2 patients with a good prognosis showed immune activation and up-regulation of tumour suppressor genes.

Conclusions

Although stratification using CMS does not outperform TNM staging as a prognostic indicator, gene-expression based subtyping shows promise for improved prognostication in stage 2 CRC.

Association of Adjuvant Chemotherapy With Overall Survival in Patients With Rectal Cancer and Pathologic Complete Response Following Neoadjuvant Chemotherapy and Resection

Importance

Adjuvant chemotherapy (AC) in patients with rectal cancer with pathologic complete response following neoadjuvant chemoradiotherapy (nCRT) and resection is recommended by treatment guidelines. However, its role in this setting is equivocal because data supporting benefits are lacking.

Objective

To compare the overall survival (OS) between AC and postoperative observation (OB) in patients with rectal cancer with pathologic complete response following nCRT and resection.

Design, Setting, and Participants

We identified a cohort of patients with rectal cancer and a complete pathological response (ypT0N0) after nCRT in the National Cancer Database between 2006 and 2012. Patients who received AC were compared with OB patients by propensity score matching. Overall survival was compared using the stratified log-rank test and stratified Cox regression model. The outcomes after AC vs OB were also evaluated in patient subgroups. The data analysis was completed in June 2017.

Exposures

Adjuvant chemotherapy and OB.

Main Outcomes and Measures

Overall survival.

Results

We identified 2764 patients (mean [SD] age, 60.0 [12.3] years; 40% female) with clinical stage II or III resected adenocarcinoma of the rectum who had received nCRT and were complete responders (ypT0N0M0). Of this cohort, 741 patients in the AC group were matched by propensity score to 741 patients who underwent OB. The AC cohort had better OS compared with the OB cohort (hazard ratio, 0.50; 95% CI, 0.32-0.79). The 1-, 3-, and 5-year OS rates were 99.7%, 97.1%, and 94.7% for the AC group and 99.2%, 93.6%, and 88.4% for the OB group (P = .005). In subgroup analysis, patients with clinical stage T3/T4 and node-positive disease benefited most from AC (hazard ratio, 0.47; 95% CI, 0.25-0.91).

Conclusions and Relevance

Adjuvant chemotherapy was associated with improved OS in patients with pathologic complete response after nCRT for resected locally advanced rectal cancer. This study supports the use of AC in this setting where there is currently paucity of data.

Validation of immunogenic PASD1 peptides against HLA-A*24:02 colorectal cancer

Colorectal cancer is the third commonest malignancy in Asia including Malaysia. The immunogenic cancer-testis antigens, which are expressed in a variety of cancers but with limited expression in normal tissues except the testis, represent an attractive approach to improve treatment options for colorectal cancer. We aimed to validate four PASD1 peptides as the immunotherapeutic targets in colorectal cancer. First, PASD1 mRNA and protein expression were determined via real-time polymerase chain reaction (RT-PCR) and immunohistochemistry. The PASD1 peptides specific to HLA-A*24:02 were investigated using IFN-y-ELISpot assay, followed by the cytolytic and granzyme-B-ELISpot assays to analyze the cytolytic effects of CD8⁺ T cells. Gene and protein expressions of PASD1 were detected in 20% and 17.3% of colorectal cancer samples, respectively. PASD1(4) peptide was shown to be immunogenic in colorectal cancer samples. CD8⁺ T cells raised against PASD1(4) peptide were able to lyze HLA-A*24:02+ PASD1+ cells. Our results reveal that PASD1(4) peptide represents a potential target for colorectal cancer.

Time from incident primary cancer until recurrence or second primary cancer: Risk factors and impact in general practice

OBJECTIVE

Specialised follow-up care after cancer treatment is changing towards increased involvement of general practice. To ensure timely detection of new cancer events, knowledge is warranted on the timing of cancer recurrence (CR) and second primary cancer (SPC), including risk factors for CR.

METHODS

This population-based register study included 67,092 patients diagnosed with malignant melanoma, bladder, lung, ovarian, endometrial, colorectal and breast cancer in Denmark in 2008-2016. The time from primary cancer to CR or SPC and risk factors for prolonged time to CR were analysed and stratified on sex and primary cancer type.

RESULTS

Cancer recurrence proportions ranged from 6% to 35%. The risk of CR increased profoundly within the first 3 years and then levelled off, except for breast cancer. A total of 3%-6% of patients had SPC, with monotonously increasing cumulative incidence proportions. Besides primary tumour characteristics, lower educational level, living alone and comorbidity were associated with earlier CR. For example, in female malignant melanoma, HRs and 95% confidence intervals were 0.47 (0.37-0.61) for high educational level, 1.40 (1.16-1.68) for living alone and 2.38 (1.53-3.70) for high comorbidity.

CONCLUSION

The results may inform stratified risk assessment in decision of frequency, location and duration of post-cancer follow-up care.

Advances in Biomaterials and Technologies for Vascular Embolization

Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology used for the deliberate occlusion of blood vessels for the treatment of diseased or injured vasculature. A wide variety of embolic agents including metallic coils, calibrated microspheres, and liquids are available for clinical practice. Additionally, advances in biomaterials, such as shape-memory foams, biodegradable polymers, and in situ gelling solutions have led to the development of novel preclinical embolic agents. The aim here is to provide a comprehensive overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. Limitations and challenges in embolic materials are also discussed to promote advancement in the field.

Hyaluronic acid synthase 2 promotes malignant phenotypes of colorectal cancer cells through transforming growth factor beta signaling

Hyaluronic acid synthase 2 (HAS2) is suggested to play a critical role in malignancy and is abnormally expressed in many carcinomas. However, its role in colorectal cancer (CRC) malignancy and specific signaling mechanisms remain obscure. Here, we report that HAS2 was markedly increased in both CRC tissue and malignant CRC cell lines. Depletion of HAS2 in HCT116 and DLD1 cells, which express high levels of HAS2, critically increased sensitivity of radiation/oxaliplatin‐mediated apoptotic cell death. Moreover, downregulation of HAS2 suppressed migration, invasion and metastasis in nude mice. Conversely, ectopic overexpression of HAS2 in SW480 cells, which express low levels of HAS2, showed the opposite effect. Notably, HAS2 loss‐ and gain‐of‐function experiments revealed that it regulates CRC malignancy through TGF‐β expression and SMAD2/Snail downstream components. Collectively, our findings suggest that HAS2 contributes to malignant phenotypes of CRC, at least partly, through activation of the TGF‐β signaling pathway, and shed light on the novel mechanisms behind the constitutive activation of HAS2 signaling in CRC, thereby highlighting its potential as a therapeutic target.

Dealing with insufficient liver remnant: Associating liver partition and portal vein ligation for staged hepatectomy

Liver resection for colorectal liver metastases has emerged to highly successful treatment in the last decades. Key to this success is complete hepatic tumor removal and systemic disease control by chemotherapy. Associating liver partition and portal vein ligation for staged hepatectomy is the most recent two-stage resection strategy for patients with very small future liver remnant making complete tumor removal possible within 1 to 2 weeks. Oncological outcome data are being collected at the moment and first results from small series reveal promising results.

Metastatic Profile of Colorectal Cancer: Interplay Between Primary Tumor Location and KRAS Status

BACKGROUND

Mutant KRAS tumors are purported to metastasize differently than wild-type KRAS tumors. The biological heterogeneity of tumors from different parts of the colon are also reported to affect metastasis. This study aims to characterize the metastatic profile by evaluating these factors in unison.

METHODS

Retrospective analysis of 899 patients with metastatic colorectal cancers treated from January 2010 to December 2014 was conducted. KRAS mutation status and primary tumors location were correlated with single-site metastasis (liver, lung, and peritoneum) and dual-site metastases (liver-peritoneum, liver-lung, and lung-peritoneum). Patients without KRAS analyses were excluded.

RESULTS

Right-sided tumors had highest frequency of peritoneal metastasis as compared to left-sided or rectal tumors (34.7% versus 15.8% versus 8.8%, P = 0.00) regardless of KRAS status (32.6% versus 38.5%, P = 0.62). Left-sided tumors with wild-type KRAS had greater proportion of liver metastasis (78.6% versus 53.5%, P = 0.00), whereas those with mutant KRAS had greater proportion of lung metastasis (23.3% versus 8.7%, P = 0.02). Rectal tumors with wild-type KRAS tend to spread to the liver (81.4% versus 48.0%, P = 0.00) and not to the peritoneum (2.3% versus 20.0%, P = 0.01). In dual-site metastases, left-sided tumors with wild-type KRAS had more liver-peritoneal metastases (75.0% versus 29.4%, P = 0.00), whereas mutant KRAS had greater lung-liver metastases (64.7% versus 20.8%, P = 0.01). Rectal tumors had the predilection for lung-liver metastases as compared to right-sided and left-sided tumors (92.3% versus 40.0% versus 39.0%, P = 0.00) regardless of KRAS status (100% versus 75%, P = 0.12).

CONCLUSIONS

Our results may streamline surveillance programs based on primary tumor location and KRAS mutational status.

Pattern, Stage, and Time of Recurrent Colorectal Cancer After Curative Surgery

Surgery remains the mainstay of curative treatment for colorectal cancer (CRC). Despite curative surgery, some patients experience cancer recurrence. However, the pattern, stage, and time of recurrent disease (RD) remain unknown. We aimed to determine the pattern and stage of RD after curative open and laparoscopic surgery for CRC. Databases were searched using selected keywords for clinical studies that analyzed the pattern, stage, and time of RD from CRC. A systematic protocol was used for data extraction, data synthesis, and interpretation of results. Of 455 publications retrieved from databases, 9 clinical studies were selected for this systematic review. There is substantial evidence that pulmonary recurrence is most commonly associated with rectal tumors, and multisite RD appears more frequently with right-sided CRC. RD from colon cancers predominantly appears early in liver, while recurrences from rectal cancer appear late in lungs. Approximately 30% to 50% of RD after curative resection of CRC occurs within the first 2 years; however, median time to recurrence is gradually increasing, particularly for patients with rectal cancers. Advanced primary CRC is significantly correlated with more locoregional and distant RD, with worse disease-free survival. There is a decrease in the 5-year incidence of RD that is associated with prolongation of time of RD for both locoregional and metastatic disease. The duration and design of postoperative follow-up protocols for recurrences from CRC should be tailored to site and stage of primary tumor, as rectal cancers demand longer surveillance times than colon cancer.

Is adjuvant chemotherapy necessary for locally advanced rectal cancer patients with pathological complete response after neoadjuvant chemoradiotherapy and radical surgery? A systematic review and meta-analysis

PURPOSE

Current clinical guidelines recommended the routine use of adjuvant chemotherapy for locally advanced rectal cancer (LARC) patients. However, the effects of adjuvant chemotherapy in patients with pathological complete response (pCR) after neoadjuvant chemoradiotherapy and radical surgery showed discrepancies in different investigations.

METHODS

A systematic review and meta-analysis were conducted using PubMed, Embase and Web of Science databases. All original comparative studies published in English that were related to adjuvant versus non-adjuvant chemotherapy for LARC patients with pCR were included.

RESULTS

A total of 6 studies based on 18 centres or databases involving 2948 rectal cancer patients with pCR (adjuvant group = 1324, non-adjuvant group = 1624) were included in our overall analysis. Based on our meta-analysis, LARC patients with pCR who received adjuvant chemotherapy showed a significantly improved overall survival (OS) when compared to patients with observation (HR = 0.65, 95% CI = 0.46-0.90, P = 0.01). In addition, investigations focused on this issue based on the National Cancer Database (NCDB) were systematically reviewed in our current study. Evidence from all three analyses demonstrated that LARC patients with clinical nodal positive disease that achieved pCR might benefit the most from additional adjuvant chemotherapy.

CONCLUSION

Our meta-analysis indicated that adjuvant chemotherapy is associated with improved OS in LARC patients with pCR after neoadjuvant chemoradiotherapy and radical surgery.

The impact of primary tumor location in patients with metastatic colorectal cancer: a Korean Cancer Study Group CO12-04 study

BACKGROUND/AIMS

Colorectal cancer is associated with different anatomical, biological, and clinical characteristics. We determined the impact of the primary tumor location in patients with metastatic colorectal cancer (mCRC).

METHODS

Demographic data and clinical information were collected from 1,115 patients from the Republic of Korea, who presented with mCRC between January 2009 and December 2011, using web-based electronic case report forms. Associations between the primary tumor location and the patient's clinical characteristics were assessed, and factors inf luencing overall survival were analyzed using Cox proportional hazards regression models.

RESULTS

Of the 1,115 patients recruited to the study, 244 (21.9%) had right colon cancer, 483 (43.3%) had left colon cancer, and 388 (34.8%) had rectal cancer. Liver and lung metastases occurred more frequently in patients with left colon and rectal cancer (p = 0.005 and p = 0.006, respectively), while peritoneal and ovarian metastases occurred more frequently in patients with right and left colon cancer (p < 0.001 and p = 0.031, respectively). The median overall survival of patients with tumors originating in the right colon was significantly shorter than that of patients whose tumors had originated in the left colon or rectum (13.7 months [95% confidence interval (CI), 12.0 to 15.5] vs. 18.0 months [95% CI, 16.3 to 19.7] or 19.9 months [95% CI, 18.5 to 21.3], respectively; p = 0.003). Tumor resection, the number of metastatic sites, and primary tumor location correlated with overall survival in the univariate and multivariate analyses.

CONCLUSION

Primary tumor location influences the metastatic sites and prognosis of patients with mCRC.