Adjuvant chemotherapy improves survival in patients with American Joint Committee on Cancer stage II colon cancer

Location matters: spatial dynamics of tumor-infiltrating T cell subsets is prognostic in colon cancer

Background

Colon cancer is a heterogeneous disease and consists of various molecular subtypes. Despite advances in high-throughput expression profiling, limitations remain in predicting clinical outcome and assigning specific treatment to individual cases. Tumor-immune interactions play a critical role, with tumors that activate the immune system having better outcome for the patient. The localization of T cells within tumor epithelium, to enable direct contact, is essential for antitumor function, but bulk DNA/RNA sequencing data lacks spatial distribution information. In this study, we provide spatial T cell tumor distribution and connect these data with previously determined genomic data in the AC-ICAM colon cancer patient cohort.

Methods

Colon cancer patients (n=90) with transcriptome data available were selected. We used a custom multiplex immunofluorescence assay on colon tumor tissue sections for quantifying T cell subsets spatial distribution in the tumor microenvironment, in terms of cell number, location, mutual distance, and distance to tumor cells. Statistical analyses included the previously determined Immunologic Constant of Rejection (ICR) transcriptome correlation and patient survival, revealing potential prognostic value in T cell spatial distribution.

Results

T cell phenotypes were characterized and CD3+CD8-FoxP3- T cells were found to be the predominant tumor-infiltrating subtype while CD3+FoxP3+ T cells and CD3+CD8+ T cells showed similar densities. Spatial distribution analysis elucidated that proliferative T cells, characterized by Ki67 expression, and Granzyme B-expressing T cells were predominantly located within the tumor epithelium. We demonstrated an increase in immune cell density and a decrease in the distance of CD3+CD8+ T cells to the nearest tumor cell, in the immune active, ICR High, immune subtypes. Higher densities of stromal CD3+FoxP3+ T cells showed enhanced survival outcomes, and patients exhibited superior clinical benefits when greater spatial distances were observed between CD3+CD8-FoxP3- or CD3+CD8+ T cells and CD3+FoxP3+ T cells.

Conclusion

Our study's in-depth analysis of the spatial distribution and densities of major T cell subtypes within the tumor microenvironment has provided valuable information that paves the way for further research into the intricate relationships between immune cells and colon cancer development.

Prediction of Survival Rate and Chemotherapy Effect by an Immune Score Model in Colorectal Cancer

Colorectal cancer is the third most common cancer and the second leading cause of cancer-related deaths. Immune cells in the tumor microenvironment play an important role in the development of tumors. In this study, CIBERSORT was used to estimate the subset of the immune cells using bulk gene expression data (i.e., TCGA, GEO, and cBioPortal databases). 1,087 samples were included in the analysis. The results revealed that among the 22 immune cell subsets that were evaluated, resting and activated NK cells, macrophage M1 and M2, and resting mast cells are associated with significant improvements in patient survival of colorectal cancer. The 15-year survival rates for the training cohort showed 49.1% and 32.5%, respectively, for the low- and high-risk groups. Likewise, the validation and entire cohorts showed 77.3% versus 47.2% and 65.3% versus 46.5%, respectively, for the low- and high-risk groups. Also, the prognostic immune score in predicting the chemotherapy effects showed that the low-risk group had a better survival superiority over the high-risk group, whether patients received chemotherapy or not. The gene set enrichment analysis showed that the low-risk group was highly enriched in pathways or processes related to immune response. The immune checkpoint assessment revealed significantly higher mRNA expressions of CTLA4 in the lower risk group than in the higher risk group. Altogether, this study offers information that could improve the prognosis of colorectal cancer.

Somatic POLE exonuclease domain mutations elicit enhanced intratumoral immune responses in stage II colorectal cancer

Previous studies found patients with POLE exonuclease domain mutations (EDMs) in targeted exons were related to significant better outcomes in stage II-III colorectal cancer (CRC). The detailed mutational profile of the entire POLE exonuclease domain, tumor mutation burden (TMB) and immune cell infiltration in POLE EDMs tumors, and the prognostic value of such mutations in stage II CRCs were largely unknown to us. This study was to clarify the characteristics, immune response and prognostic value of somatic POLE EDMs in stage II CRC. A total of 295 patients with stage II CRC were sequenced by next-generation sequencing with a targeted genetic panel. Simultaneous detection of the immune cells was conducted using a five-color immunohistochemical multiplex technique. The detailed molecular characteristics, tumor-infiltrating lymphocyte (TIL) and prognostic effect of POLE EDMs in stage II CRC were analyzed. For stage II CRCs, the POLE EDMs were detected in 3.1% of patients. Patients with POLE EDMs were more prone to be microsatellite instability-high (MSI-H) (33.3% vs 11.2%, p=0.043), younger at diagnosis (median 46 years vs 62 years, p<0.001) and more common at right-sided location (66.7% vs 23.1%; p=0.003). All patients with POLE EMDs were assessed as extremely high TMB, with a mean TMB of 200.8. Compared with other stage II CRCs, POLE EDMs displayed an enhanced intratumoral cytotoxic T cell response, evidenced by increased numbers of CD8+TILs and CD8A expression. Patients with stage II CRCs could be classified into three risk subsets, with significant different 5 years disease-free survival rates of 100% for POLE EDMs, 82.0% for MSI-H and 63.0% for MSS, p=0.013. In conclusion, characterized by a robust intratumoral T cell response, ultramutated POLE EDMs could be detected in a small subset of stage II CRCs with extremely high TMB. Patients with POLE EDMs had excellent outcomes in stage II CRCs, regardless of MSI status. Sequencing of all the exonuclease domain of POLE gene is recommended in clinical practice.

Lymphovascular Invasion and Perineural Invasion Negatively Impact Overall Survival for Stage II Adenocarcinoma of the Colon

BACKGROUND

Lymphovascular invasion and perineural invasion are histopathological features associated with higher-risk colon cancer.

OBJECTIVE

The purpose of this study was to quantify the impact of lymphovascular and perineural invasion on overall survival after diagnosis and to determine the protective effect of adjuvant chemotherapy for early adenocarcinoma with high-risk factors.

DESIGN

This was a retrospective database review of the 2010-2014 National Cancer Database for colon cancer.

SETTINGS

Individuals diagnosed with invasive adenocarcinoma of the colon (histology code 8140) with primary surgical resection with >12 nodes harvested and no positive nodes on pathological examination were included.

PATIENTS

A total of 32,493 patients underwent surgical resection for stage II adenocarcinoma of the colon.

INTERVENTIONS

The study involved multivariate Cox regression analysis of the impact of lymphovascular and perineural invasion and adjuvant chemotherapy on overall survival after a diagnosis of stage II adenocarcinoma of the colon.

MAIN OUTCOME MEASURES

Survival after a diagnosis of stage II adenocarcinoma of the colon was measured.

RESULTS

Five-year survival after diagnosis and surgical resection without adjuvant chemotherapy was lower for patients with lymphovascular (60.0%), perineural (56.9%), and lymphovascular and perineural invasion (55.8%) compared with double-negative disease (66.1%). Log-rank testing confirmed that adjuvant chemotherapy improved 5-year survival after diagnosis for lymphovascular (85.5%), perineural (83.6%), and lymphovascular and perineural invasion (74.3%). After controlling for differences in cohorts, Cox regression analysis showed an increased HR for mortality of 14.0% for lymphovascular (HR = 1.141 (95% CI, 1.060-1.228)), 32.1% for perineural (HR = 1.321 (95% CI, 1.176-1.483)), and 41.0% for lymphovascular and perineural invasion (HR = 1.409 (95% CI, 1.231-1.612)) compared with having neither. Chemotherapy showed a 43% reduction in hazard for mortality (HR = 0.570 (95% CI, 0.513-0.633)).

LIMITATIONS

The study was limited by its retrospective review and observational bias.

CONCLUSIONS

Lymphovascular and perineural invasion have a detrimental effect on survival after diagnosis of stage II adenocarcinoma of the colon. Chemotherapy may be protective specifically when lymphovascular and perineural invasion are present. See Video Abstract at http://links.lww.com/DCR/A786.

T4 Colon Cancer - Current Management

Colorectal cancer is the third most often encountered type of cancer and represents the third leading cause of cancer related deaths, on both sexes. One of the most important prognostic parameters is the tumor’s stage at the time of the diagnosis. T4 cancers represent advanced tumors associated with penetration of the visceral peritoneum (T4a) and/or direct invasion in adjacent structures (T4b). Preoperative diagnosis is influenced by the inability of the existent imaging modalities to accurately differentiate the true invasion from the simple, inflammatory adherence to the neighboring structures. As a consequence surgical treatment must follow the principle of en bloc resection; however the ability of achieving an R0 resection depends on the tumor location, invaded organ, and the type of the surgical procedure required. Neoadjuvant treatment for advanced colon cancer it may be very difficult to be applied. This review is focused on preoperative workup, therapeutic strategies and subsequent results in advanced T4 colon cancers.

Extramural Venous Invasion as Prognostic Factor of Recurrence in Stage 1 and 2 Colon Cancer

Aim

Extramural venous invasion (EMVI) is a prognostic indicator in patients with colorectal cancer. However, its additional value in patients with stage 1 and 2 colorectal cancer is uncertain. In the present study, the incidence of EMVI and the hazard ratio for recurrence in patients with stage 1 and 2 colon cancer were studied.

Methods

184 patients treated for stage 1 and 2 colon cancer were included with a follow-up of at least 5 years. Chart review was performed and EMVI was assessed by two separate pathologists. EMVI was scored with additional caldesmon staining on the resection specimen. Primary outcomes were recurrence-free survival (RFS) measured through the Cox regression analysis and prevalence of EMVI.

Results

There were 10 cases of EMVI and 3 cases of intramural venous invasion (IMVI) all occurring in patients with stage 2 disease corresponding to a prevalence of 9%. Thirty-one percent of the patients with venous invasion experienced recurrence versus 14% in patients without, corresponding with a hazard ratio of 2.39 (p = 0.11).

Conclusion

The present study demonstrates a trend towards an increased risk of recurrence in patients with stage 2 colon cancer with venous invasion. This warrants consideration of adjuvant chemotherapy despite the lack of lymph node metastases.

Examining the impact of regular aspirin use and PIK3CA mutations on survival in stage 2 colon cancer

BACKGROUND/AIM

Data suggest aspirin improves survival in colorectal cancer (CRC) harbouring PIK3CA mutations. The impact of aspirin is thought predominantly to be through an anti-inflammatory effect. The aim of this study is to explore the effect of aspirin use on survival in a real-world cohort of stage 2 colon cancer (CC) patients.

METHODS

A prospective CRC database identified patients diagnosed with stage 2 CC between 2000 and 2011. PIK3CA mutation status was determined by next generation sequencing. Neutrophil-lymphocyte ratio greater than 5 at diagnosis represented systemic inflammation. Chart review was used to record regular aspirin use at diagnosis. Clinico-pathological features and survival data were available. Survival analyses used the Cox proportional hazards method.

RESULTS

Of 488 patients with stage 2 CC, 95 patients were aspirin users and 70 patients had PIK3CA mutations. Aspirin users were more likely to be older (median: 76.4 years vs 68.3 years, P < 0.001), to be less fit (American Society of Anaesthetists Score 3-4: 58% vs 31%, P < 0.001) and to have systemic inflammation (neutrophil-lymphocyte ratio > 5: 39% vs 27%, P = 0.027). Regular aspirin use did not significantly improve recurrence-free survival. In the PIK3CA mutated group, there was a trend towards improved recurrence-free survival (hazard ratio: 0.45, P = 0.42).

CONCLUSIONS

Our study did not demonstrate a significant survival advantage from aspirin use in stage 2 PIK3CA mutated CC. The 'real-world' nature of our cohort and the subsequent uncontrolled differences in age and fitness in aspirin users are likely to have contributed to this result. Defining the true impact of aspirin in CRC requires prospective randomised clinical trials.

Adjuvant chemotherapy is associated with improved survival in patients with stage II colon cancer

BACKGROUND

The role of adjuvant chemotherapy in patients with stage II colon cancer remains to be elucidated and its use varies between patients and institutions. Currently, clinical guidelines suggest discussing adjuvant chemotherapy for patients with high-risk stage II disease in the absence of conclusive randomized controlled trial data. To further investigate this relationship, the objective of the current study was to determine whether an association exists between overall survival (OS) and adjuvant chemotherapy in patients stratified by age and pathological risk features.

METHODS

Data from the National Cancer Data Base were analyzed for demographics, tumor characteristics, management, and survival of patients with stage II colon cancer who were diagnosed from 1998 to 2006 with survival information through 2011. Pearson Chi-square tests and binary logistic regression were used to analyze disease and demographic data. Survival analysis was performed with the log-rank test and Cox proportional hazards regression modeling. Propensity score weighting was used to match cohorts.

RESULTS

Among 153,110 patients with stage II colon cancer, predictors of receiving chemotherapy included age <65 years, male sex, nonwhite race, use of a community treatment facility, non-Medicare insurance, and diagnosis before 2004. Improved and clinically relevant OS was associated with the receipt of adjuvant chemotherapy in all patient subgroups regardless of high-risk tumor pathologic features (poor or undifferentiated histology, <12 lymph nodes evaluated, positive resection margins, or T4 histology), age, or chemotherapy regimen, even after adjustment for covariates and propensity score weighting (hazard ratio, 0.76; P<.001). There was no difference in survival noted between single and multiagent adjuvant chemotherapy regimens.

CONCLUSIONS

In what to the authors' knowledge is the largest group of patients with stage II colon cancer evaluated to date, improved OS was found to be associated with adjuvant chemotherapy regardless of treatment regimen, patient age, or high-risk pathologic risk features. Cancer 2016;122:3277-3287. © 2016 American Cancer Society.

Prognostic factors and the role of adjuvant chemotherapy in post-curative surgery for Dukes B and C colon cancers and survival outcomes: a Malaysian experience

BACKGROUND

Adjuvant chemotherapy improves survival in Dukes C colon cancers post-curative resection. However, the evidence for a role with Dukes B lesions remains unproven despite frequent use for disease characterized by poor prognostic features. In view of limited Asia-specific data, this study aimed to determine survival outcomes and identify prognostic factors in a tertiary teaching hospital in Malaysia.

MATERIALS AND METHODS

A total of 116 subjects who underwent curative surgery with and without adjuvant chemotherapy for Duke B and C primary colon adenocarcinomas diagnosed from 2004-2009 were recruited and data were collected retrospectively. Five-year overall survival (OS) and disease free survival (DFS) were analysed using Kaplan-Meier survival analysis and log-rank (Mantel-Cox) test. Prognostic factors were determined using Cox proportional hazards regression with both univariate and multivariate analyses.

RESULTS

The survival analysis demonstrated a 5-year OS of 74.0% for all patients, with 74.9% for Dukes C subjects receiving chemotherapy compared to 28.6% in those not receiving chemotherapy (p=0.001). For Dukes B disease, the 5-year survival rate was 82.6% compared to 75.0% for subjects receiving and not receiving chemotherapy, respectively (p=0.17). Independent prognostic factors identified included a CEA level more than 3.5 ng/ml (hazard ratio (HR)=4.78; p=0.008), serosal involvement (HR=3.75; p=0.028) and completion of chemotherapy (HR= 0.20; p=0.007).

CONCLUSIONS

In a regional context, this study supports current evidence from the West that adjuvant chemotherapy improves survival in Dukes C colon cancers post curative surgery. However, although a clear benefit has yet to be proven for Dukes B disease, our results suggest survival improvement in selected cases.

High Risk Stage 2 and Stage 3 Colon Cancer, Predictors of Recurrence and Effect of Adjuvant Therapy in a Nonselected Population

Patients with stage 2 and stage 3 colon cancer often are treated with adjuvant chemotherapy. However, patients seen in daily practice have more comorbidity than those enrolled in clinical trials. This study aims to evaluate prognostic factors for recurrence and to ascertain the benefit of adjuvant chemotherapy on recurrence-free survival (RFS) of patients in a nonselected population. Furthermore, the impact of relative dose intensity (RDI) of adjuvant therapy on RFS is examined. Chart review was performed for 243 consecutive patients diagnosed and treated at a single center for stage 2 and stage 3 colon cancer from 2002 to 2008. Adjuvant chemotherapy was administered to 66 patients. Median overall survival (OS) was 5.84 years and median RFS was 5.37 years. For stage 2 disease, patients treated with or without adjuvant therapy had a median RFS of 5.49 and 5.73, respectively (p = ns). For stage 3 disease, median RFS rates were 5.08 and 1.19, respectively (p = 0.084). Overall RDI of oxaliplatin based chemotherapy higher than median was associated with increased RFS (p = 0.045). In conclusion, adjuvant therapy did not significantly increase recurrence-free survival. This could be the result of comorbidity in patients. Relative dose intensity of oxaliplatin based therapy is associated with RFS.

Initial safety report on the tolerability of modified FOLFOX6 as adjuvant therapy in patients with curatively resected stage II or III colon cancer (JFMC41-1001-C2: JOIN trial)

PURPOSE

Adjuvant FOLFOX is a widely accepted standard therapy for resected colon cancer. The incidence of grade 3-4 peripheral sensory neuropathy (PSN) was 12.4 and 5.7 % in the MOSAIC and Eastern MASCOT trials, while that of grade 3-4 allergic reactions (AR) was 2.9 and 3.1 %, respectively. The JFMC41-1001-C2 trial (JOIN trial) investigated the tolerability of modified FOLFOX6 (mFOLFOX6) in Japanese colon cancer patients.

METHODS

Twelve cycles of mFOLFOX6 were given to patients with the same eligibility criteria as in the MOSAIC study: stage II or III curatively resected colon cancer, performance status of 0-1, aged 20 years or older, starting mFOLFOX6 within 7 weeks of surgery, and adequate organ function. The primary endpoints were the incidence of PSN persisting for ≥8 days that interfered with daily activities and the incidence of grade 3-4 AR. The target sample size was 800.

RESULTS

From November 2010 to March 2012, 882 patients were enrolled at 198 institutions. Safety was analyzed in 828 patients with finalized data out of 848 patients receiving mFOLFOX6. The incidence of PSN persisting ≥8 days was 3.3 % [95 % confidence interval (CI) 2.2-4.7], while that of grade 3-4 AR was 1.7 % (95 % CI 0.9-2.8). The treatment completion rate was 67.0 %. The median total dosage of oxaliplatin was 811.1 mg/m(2). The overall incidence of grade 3-4 PSN was 5.8 %. Interstitial pneumonitis occurred in one patient. There were no treatment-related deaths.

CONCLUSIONS

Adjuvant mFOLFOX6 is tolerable for Japanese patients with colon cancer.

Survival paradox between stage IIB/C (T4N0) and stage IIIA (T1-2N1) colon cancer

BACKGROUND

The survival paradox between stage IIB/C (T4N0) and stage IIIA (T1-2N1) colon cancer remains in the 7th edition of the American Joint Committee on Cancer staging system. This multicenter study aimed to compare the oncologic outcomes of T4N0 and T1-2N1 colon cancers and to investigate the presumptive prognostic factors that might influence the survival paradox.

METHODS

Patients who underwent curative surgery for pT4N0 (n = 224) and pT1-2N1 (n = 135) primary colon cancer between January 1999 and December 2010 at five tertiary referral cancer centers were included for analysis. The clinicopathologic, treatment-related factors, and oncologic outcomes in terms of the 5-year overall survival (5-OS) and 5-year disease-free survival (5-DFS) were compared.

RESULTS

The T4N0 group had significantly worse 5-OS and 5-DFS rates than the T1-2N1 group (5-OS: 84.0 vs. 92.3 %, p = 0.012; 5-DFS: 73.6 vs. 88.0 %, p = 0.001). T4N0 cancers more frequently showed elevated preoperative carcinoembryonic antigen, lower grade of differentiation, larger tumor size, and higher proportions of perineural invasion, microsatellite instability, obstruction, and perforation than T1-2N1 cancers. Peritoneal seeding and liver metastasis were the predominant recurrence pattern in the T4N0 and T1-2N1 groups, respectively (p = 0.042). The T4N0 group showed inferior survival to the T1-2N1 group in postoperative adjuvant chemotherapy (5-OS: 87.1 vs. 93.2 %, p = 0.045; 5-DFS: 76.1 vs. 89.0 %, p = 0.001).

CONCLUSIONS

T4N0 colon cancer had significantly worse oncologic outcomes than T1-2N1 cancer regardless of adjuvant chemotherapy. The survival paradox may result from the biologic aggressiveness of T4N0 colon carcinomas.

TNM staging of colorectal cancer should be reconsidered by T stage weighting

AIM: To verify that the T stage has greater weight than the N stage in the staging of colorectal cancer.

METHODS: Open data from the Surveillance, Epidemiology, and End Results program were reviewed and analyzed according to the T stage, N stage, and patients’ observed survival (OS). The relative weights of the T and N stages were calculated by multiple linear regressions based on their impact on survival. Risk scores for 25 TN categories were then calculated from the T and N stage relative weights, and a rearranged tumor node metastasis (TNM) staging system was proposed via a cluster analysis of the TN scores.

RESULTS: Both T and N stages significantly affect the OS of patients with colorectal cancer. Moreover, the T stage has greater weight than the N stage in the TNM staging system of colorectal cancer. For colon cancer, the relative T and N stage weights were 0.58 and 0.42, respectively, and for rectal cancer, the relative T and N stage weights were 0.61 and 0.39, respectively. On the basis of cluster analysis of the TN scores, T1N1a was classified to stage I, and T2N1a-1b and T1N1b-2a were classified to stage II in our revised TNM staging system for both colon and rectal cancer. For colon cancer, T4bN0 was classified to stage IIIa, but for rectal cancer, it was classified to stage IIIb.

CONCLUSION: As the T stage affects colorectal cancer survival more significantly than the N stage, the TNM staging should be revised by relative T stage weight.

Prognostic factors of stage Ⅱa colon cancer

AIM: To investigate the prognostic factors of stage Ⅱa (pT3N0M0) colon cancer.

METHODS: The demographic, clinical and laboratory data for 161 patients with stage Ⅱa colon cancer treated with curative surgery alone at Peking University Cancer Hospital from January 2004 to June 2008 were reviewed retrospectively. Eighty-four valid cases were selected in this study based on inclusive and exclusive criteria. The 3-year disease-free survival (DFS) was tested by univariate and multivariate analyses to identify prognostic factors.

RESULTS: The overall 3-year DFS for the selected 84 cases was 88.1%. The 3-year DFS for patients with elevated CEA levels was significantly lower than those with normal CEA levels (76.5% vs 95.8%, P = 0.007). Multivariate analysis demonstrated that CEA level (OR = 8.013, 95% CI 1.573-40.817, P = 0.012), expression of Ki67 (OR = 3.298, 95% CI 0.799-13.610, P = 0.099), male gender (OR = 7.212, 95% CI 1.293-40.237, P = 0.024) and anemia (OR = 6.461, 95% CI 1.537-27.151, P = 0.011) were independent prognostic factors for the 3-year DFS. Stratified analysis revealed that elevated level of CEA combined with high expression of Ki67 was associated with a poorer prognosis (3-year DFS = 70%).

CONCLUSION: Elevated preoperative serum level of CEA and high expression of Ki67 in cancer tissue are predictors of poor prognosis for stage Ⅱa colon cancer. More intensive adjuvant treatment should be considered in patients with such high risk factors.

Clinical management of localized colon cancer with capecitabine

Large randomized trials demonstrated a benefit of adjuvant chemotherapy after resection of the primary colon cancer. It improves overall survival and reduces the risk of death, by 5% in UICC (Union Internationale Contre le Cancer) stage II and approximately 15%-20% in stage III. Fluoropyrimidines have been the standard drugs for the treatment of colon cancer since large randomized controlled trials demonstrated their efficacy and safety in treating patients suffering from this disease. Capecitabine is an orally administered fluoropyrimidine, which is preferably activated in tumor tissue to the active moiety 5-fluorouracil (5FU) and is cytotoxic through inhibition of DNA synthesis. It has proven equivalent efficacy and tolerability despite a changed toxicity profile compared to 5FU with less myelosuppression but more hand-and-foot syndrome. Capecitabine is well tolerated in elderly patients. The oral route of administration avoids frequent clinical visits as well as insertion of central venous catheters. The impact of the particular drug features on daily clinical practice is discussed in this review.