Towards exertion of immunotherapeutics in the treatment of colorectal cancer; adverse sides, challenges, and future directions

Immunotherapy has growingly been prosperous as a promising therapeutic option for several kinds of solid tumors, such as colorectal cancer (CRC), subsequent to initial successful outcomes in the treatment of melanoma. The use of immunotherapy, like nivolumab and pembrolizumab (which are monoclonal antibodies against programmed cell death 1) has shown prosperous outcomes in a group of CRC patients who represent mismatch-repair-deficient and microsatellite instability-high (dMMR-MSI-H). However, a successful outcome of treatment by immune checkpoint inhibitors (ICIs) has not been observed in all of the metastatic CRC patients with dMMR-MSI-H tumors. ICIs are able to block the co-inhibitory signaling transduced in T cells, resulting in increased cytotoxic activity of T cells and efficient killing of tumor cells. In spite of availability of diverse immunotherapeutics in treatment of advanced CRC, a poor survival rate of such approaches has been reported along with challenges in the clinical practice. It is necessary to identify novel biomarkers and molecular signatures to approximate the outcome of ICI therapy in the metastatic CRC patients with dMMR-MSI-H tumors. Here we tried to clarify the current line of evidence regarding immunotherapeutics in the treatment of CRC, and discuss the challenges and hurdles in the management of these patients.

Elevated Neutrophil-to-Lymphocyte Ratio in Perioperative Periods is Suggestive of Poor Prognosis in Patients with Colorectal Cancer

Background

Recent data suggest that alterations in the neutrophil-to-lymphocyte ratio (NLR) in the perioperative periods can serve as prognostic factors. However, research on the clinical impact has been limited and even discordant in patients with colorectal cancer (CRC).

Patients and Methods

The optimal cut-off value of preoperative NLR (NLR-pre), postoperative NLR (NLR-post), and its change (NLR-delta) were determined to maximize differences in overall survival (OS) between groups. Patients were categorized into four groups (NLR-trend) as follows: G1, low NLR-pre and NLR-post; G2, low NLR-pre and high NLR-post; G3, high NLR-pre and low NLR-post; and G4, high NLR-pre and NLR-post. Discriminatory performance was compared using integrated AUC (iAUC) between all indicators.

Results

A total of 576 patients diagnosed with stage I–IV CRC were included. The cut-off points were determined as 2.33 for NLR-pre, 2.06 for NLR-post, and −1.08 for NLR-delta. Subgroup dichotomization using NLR-pre, NLR-post, NLR-delta and NLR-trend were all identified as significant prognostic factors by univariate analysis. However, NLR-trend was only remained as an independent prognostic factor in the multivariate analysis. The iAUC of the NLR-trend was superior to that of NLR-pre (bootstrap iAUC mean difference=0.036; 95% CI 0.013–0.073), NLR-post (bootstrap iAUC mean difference=0.045; 95% CI 0.019–0.081) and NLR-delta (bootstrap iAUC mean difference=0.061; 95% CI 0.025–0.104).

Conclusion

Risk stratification and combining of preoperative and postoperative NLR (NLR-trend) can improve prognostic discrimination compared with single measurements or simple changes in NLR in patients with CRC.

Nuclear translocation of ATG5 induces DNA mismatch repair deficiency (MMR-D)/microsatellite instability (MSI) via interacting with Mis18α in colorectal cancer

BACKGROUND AND PURPOSE

It is well known that microsatellite instability-high (MSI-H) is associated with 5-fluorouracil (5-FU) resistance in colorectal cancer. MSI-H is the phenotype of DNA mismatch repair deficiency (MMR-D), mainly occurring due to hypermethylation of MLH1 promoter CpG island. However, the mechanisms of MMR-D/MSI-H are unclear. We aim to investigate the pathway of MMR-D/MSI-H involved in 5-FU resistance.

EXPERIMENTAL APPROACH

Human colorectal cancer specimens were diagnosed for MSI-H by immunohistochemistry and western blotting. Proteome microarray interactome assay was performed to screen nuclear proteins interacting with ATG5. Nuclear ATG5 and ATG5-Mis18α overexpression were analysed in ATG5^high colorectal cancer bearing mice. The methylation assay determined the hypermethylation of hMLH1 promoter CpG island in freshly isolated human colorectal cancer tissue samples and HT29^atg5 and SW480^atg5 cancer cells.

KEY RESULTS

In ATG5^high colorectal cancer patients, 5-FU-based therapy resulted in nuclear translocation of ATG5, leading to MSI-H. Colorectal cancer in Atg5 Tg mice demonstrated 5-FU resistance, compared to Atg5^+/- and WT mice. Proteome microarray assay identified Mis18α, a protein localized on the centromere and a source for methylation of the underlying chromatin, which responded to the translocated nuclear ATG5 leading to ATG5-Mis18α conjugate overexpression. This resulted in MLH1 deficiency due to hypermethylation of hMLH1 promoter CpG island, while the deletion of nuclear Mis18α failed to induce ATG5-Mis18α complex and MMR-D/MSI-H.

CONCLUSIONS AND IMPLICATIONS

Nuclear ATG5 resulted in MMR-D/MSI-H through its interaction with Mis18α in ATG5^high colorectal cancer cells. We suggest that ATG5-Mis18α or Mis18α may be a therapeutic target for treating colorectal cancer.

High level of unmet needs and anxiety are associated with delayed initiation of adjuvant chemotherapy for colorectal cancer patients

AIMS

Adjuvant chemotherapy is recommended for patients with curatively resected colorectal cancer. The aim of this study is to evaluate the impact of unmet supportive care needs and anxiety on the initiation of postoperative adjuvant chemotherapy in colorectal cancer patients.

METHODS

This is a retrospective study from a single tertiary referral hospital. Patients diagnosed with colorectal cancer who met the inclusion criteria were included. The Hospital Anxiety and Depression Scale (HADS) and modified 34-item Supportive Care Needs Survey (SCNS-SF34) were applied to assess patient's anxiety level and unmet needs. The time intervals between initiation of adjuvant chemotherapy and operation were recorded. Factors associated with delayed initiation of chemotherapy were investigated in univariate and multivariate analysis.

RESULTS

A total of 135 patients with colorectal cancer were included. In total, 16.3% (22/135) and 5.2% (7/135) reported symptoms of anxiety and depression. In multivariate analysis, low to moderate income status, postoperative complications, anxiety, and high level of unmet needs are independent risk factors for late initiation of chemotherapy.

CONCLUSIONS

Our findings showed that psychological problems such as anxiety and high unmet supportive needs are correlated with delayed initiation of adjuvant chemotherapy in colorectal cancer patients.

Preoperative Nutritional Status Contributes to the Development of Neutropenia Event in Patients With Gastric Cancer Receiving CAPEOX Adjuvant Chemotherapy

Purpose: The aim of this study is to evaluate the risk factors for ≥ grade 3 neutropenia in gastric cancer patients receiving postoperative adjuvant chemotherapy. Methods: This is a retrospective study from a single tertiary referral hospital. Patients diagnosed with gastric cancer who met the inclusion criteria were included in this study. Baseline and clinicopathological characteristics of the patients were collected. Patients were followed-up for 12 months and the incidence of neutropenia were recorded. Factors associated with neutropenia of chemotherapy in cycle 1 were investigated. Results: A total of 202 patients with gastric cancer were included. All patients received oxaliplatin plus oral capecitabine (CAPEOX) as the adjuvant chemotherapy. The incidence of ≥ grade 3 neutropenia is 11.9% (24/202) in cycle 1 among all patients. In multivariate analysis, independent risk factors for ≥ grade 3 neutropenia were serum prealbumin level (p = 0.041), prognostic nutritional index (PNI) (p = 0.049) and pre-cycle neutrophil count (p = 0.007). Conclusions: Our findings for the first time showed that nutritional parameter as prealbumin level and PNI are independent risk factors for neutropenia in gastric cancer patients receiving adjuvant chemotherapy. This may provide evidence for further investigation on prophylaxis use of granulocyte colony-stimulating factor in selected high-risk patients to prevent sever neutropenia in cycle 1 of adjuvant chemotherapy.

Prognostic significance of circulating tumor cells (CTCs) in Egyptian non-metastatic colorectal cancer patients: A comparative study for four different techniques of detection (Flowcytometry, CellSearch, Quantitative Real-time PCR and Cytomorphology)

PURPOSE

We assessed CTCs counts in NMCRC patients using four different techniques.

METHODS

CTCs were detected in 63 NMCRC patients, 40 benign bowel diseases (BBD) and 40 normal controls (NC) using, flow-cytometry (FCM), CellSearch (CS), cytomorphology and quantitative real time (qPCR) for CK19, MUC1, CD44, CD133, ALDH1 expression. Results were correlated to progression free (PFS) and overall (OS).

RESULTS

Positive CTCs (≥4 cells /7.5 mL blood) were detected in 50.8% (32/63) NMCRC by FCM and 7.5% (3/40) BBD (p < .001). CTCs were detected in 34/63 (54%) NMCRC, 4/40 (10%) BBD (p < .001) by CS. CK19, MUC1, CD44, CD133 and ALDH1 were expressed in 35 (55.6%), 29 (46.0%), 28 (44.4%), 26 (41.3%) and 25 (41.3%) cases of NMCRC. In BBD 4/40 (10%) cases expressed CK19, MUC1 and CD44, while 2/40 (5%) expressed CD133. Cytomorphology showed the lowest sensitivity (47.6%) and specificity (90%) for CTCs detection. The combined use of FCM or CS with CTCs-mRNA markers improved the sensitivity and specificity to 68.3%, and 95.0%; respectively. Positive CTCs and mRNA markers expression were significantly associated with shorter 5-yr PFS and OS. In multivariate analysis, CTCs mRNA markers were independent prognostic factors for PFS and OS.

CONCLUSIONS

Enumeration of CTCs by FCM and RNA expression for specific colon cancer markers are comparable to CS regarding sensitivity and specificity. CTCs also represent novel therapeutic targets for NMCRC cases.

Prognostic Relevance of the Timing of Initiating and the Completion of Adjuvant Therapy in Patients with Resected Pancreatic Ductal Adenocarcinoma

BACKGROUND

Although the role of adjuvant therapy in patients with pancreatic ductal adenocarcinoma (PDAC) is well established, its optimal timing and duration are still controversial.

METHODS

The study included 311 patients with PDAC who underwent curative resection followed by adjuvant therapy. We analyzed survival data according to the timing of initiation and completion of adjuvant therapy.

RESULTS

There were no differences in 5-year overall survival (OS) (32.8 vs. 35.4%, p = 0.539) and disease-free survival (DFS) rates (26.2 vs. 23.3%, p = 0.865) between early (≤6 weeks) and late (>6 weeks) initiation of adjuvant therapy. However, the 5-year OS (42.6 vs. 22.2%, p < 0.001) and DFS (29.2 vs. 18.4%, p = 0.042) rates were significantly greater in patients with complete versus incomplete adjuvant therapy. Multivariable analysis revealed that incomplete adjuvant therapy was an independent prognostic factor for decreased OS (p = 0.001; hazard ratio 1.850; 95% confidence interval 1.266-2.702).

CONCLUSIONS

The results show that complete adjuvant therapy is a more important prognostic factor than early initiation for improving the survival of patients with resected PDAC.

Age and factors associated with access and time to post-operative adjuvant chemotherapy in colon cancer: a French epidemiological study

Background

Studies have shown the negative prognostic impact of increased time between colectomy and postoperative adjuvant chemotherapy (AC) in colon cancer (CC). Our aim was to investigate the role of age and non-organizational factors on access and time to AC.

Methods

All adult patients undergoing surgery for stage II or III CC in the "Région Centre-Val de Loire" in 2013, were selected. Time to AC and socio-demographic factors were collected. Logistic regression modeling was used to identify factors associated with access to AC, and a multivariate analysis performed to identify factors associated with time to AC.

Results

Among 404 stage II or III patients who underwent colectomy, 182 (45%; sex ratio 1.5; mean age 67.6 years; range 32-90) received AC. AC patients were younger than those without AC (67.6 vs. 77.9 years) and the difference was even greater for stage III patients (69.0 vs. 82.4). The median time to AC was 48 days, exceeding 42 days in 60% of cases. Living alone, postoperative morbidities, and emergency colectomy were independently associated with increased time to AC. Age and other factors were not associated with delayed AC.

Conclusions

Emergency colectomy, postoperative morbidities, and living alone are associated with increased time to AC. Organizational measures to reduce the time to AC are therefore unlikely to have an impact. In contrast, age is not associated with increased time to AC, but to access to AC. Reasons for omitting AC in older patients requires further study.

Initiation of adjuvant chemotherapy within 8 weeks of elective colorectal resection improves overall survival regardless of reoperation

AIM

Reoperation after elective colorectal resection may delay the start of adjuvant chemotherapy (AC). The study investigated the dual impact of a reoperation and AC delay on overall survival (OS).

METHOD

The Hospital Episode Statistics database was analysed between 1997 and 2012. Patients were divided into colon and rectal cancer cohorts and data were analysed based on whether there was delay in receiving AC beyond 8 weeks and whether a patient suffered reoperation within 30 days. Multivariate regression analysis was undertaken to investigate the relationship between delay in giving AC and reoperation and their combined effect on OS.

RESULTS

Logistic regression showed reoperation, amongst other things, to be an independent predictor of AC delay, in both colon and rectal cancer (colon, odds ratio 2.31, P < 0.001; rectal, odds ratio 2.19, P < 0.001). There was no significant difference in OS between patients who had no AC delay but suffered a reoperation and patients who had no AC delay and no reoperation. Patients who had AC delay but no reoperation, however, had significantly worse OS compared to those who had no AC delay and no reoperation [colon, hazard ratio (HR) 1.16, P < 0.001; rectal, HR 1.17, P < 0.001]. Individuals who had both AC delay and a reoperation also had worse OS compared with patients who had neither (colon, HR 1.33, P = 0.037; rectal, HR 1.38, P < 0.001).

CONCLUSION

Delayed receipt of AC beyond 8 weeks after surgery is associated with significantly reduced OS regardless of reoperation status in both colon and rectal cancer patients.

The impact of adjuvant chemotherapy timing on overall survival following colorectal cancer resection

BACKGROUND

Several studies including two meta-analyses have showed that delay between surgery and adjuvant chemotherapy adversely impacts colorectal cancer survival. This study investigated this impact at a population level over a fifteen year period in England.

METHODS

The Hospital Episode Statistics database was analysed between 1997 and 2012. Colonic cancer and rectal cancer patients were collated and multivariate Cox regression analyses were undertaken to ascertain the relationship between chemotherapy delay and overall survival.

RESULTS

A total of 181 984 patients underwent resection without any reoperation (106 477 (58.5%) having colonic cancer and 75 507 (41.5%) having rectal cancer). In total, 30 836 (16.9%) received adjuvant chemotherapy. 9019 (49.3%), 4573 (25.0%), 2587 (14.1%), 1323 (7.2%) and 804 (4.4%) of 18 306 colonic cancer patients received within 8 weeks, 8-10 weeks, 10-12 weeks, 12-14 weeks and 14-16 weeks, respectively. Sequentially worse overall survival was observed: <8 weeks: Ref; 8-10 wks: Hazard Ratio (HR) 1.09; 10-12 wks: HR 1.13; 12-14 wks HR 1.32 and 14-16 wks: HR 1.32, p < 0.001. 5625 (44.9%), 3087 (24.6%), 1940 (15.5%), 1162 (9.3%) and 716 (5.7%) of 12 530 rectal cancer patients received within 8 weeks, 8-10 weeks, 10-12 weeks, 12-14 weeks and 14-16 weeks, respectively. Sequentially worse overall survival was observed: <8 weeks: Ref; 8-10 wks: HR 1.09; 10-12 wks: HR 1.22; 12-14 wks HR 1.23 and 14-16 wks: HR 1.31, p < 0.001.

CONCLUSION

Adjuvant chemotherapy delay adversely impacts colonic and rectal cancer survival. Efforts to prevent complications such as reoperation and to improve access to chemotherapy services, will improve survival in this patient cohort.

Timeliness of adjuvant chemotherapy for stage III adenocarcinoma of the colon: a measure of quality of care

BACKGROUND

Findings from multiple clinical trials established AC as a standard of care for stage III colon cancer. However, there is no recommended standard time for delivery of AC. We explored the timeliness of AC with FOLFOX as a predictor of recurrence and its role as a quality indicator in patients with stage III colon cancer.

PATIENTS AND METHODS

We conducted a retrospective analysis of patients with colon cancer who received AC at Los Angeles County Hospital and Norris Cancer Center between 2003 and 2011. Time to recurrence (TTR) was the primary end point of the study, Kaplan-Meier curves and log-rank tests were used to assess the association between timing of the AC and TTR.

RESULTS

We identified 102 patients with stage III colon cancer who had received AC. With a median follow-up of 3.2 years, time from surgery to AC was not a predictor of recurrence (P = .19). However, there was a nonsignificant trend toward higher risk of systemic recurrence when the delay of AC was more than 12 weeks (P = .068). Additionally, a significant association was found between age, race, type of hospital, and timeliness of AC.

CONCLUSION

To date, our study is the largest data set to assess the timeliness of FOLFOX as a predictor of outcome in stage III colon cancer. Because FOLFOX is the current standard for AC for colon cancer, we report a trend toward worse outcome when FOLFOX is delayed more than 12 weeks. This result, thus supports quality measures to assess the timeliness of AC in stage III colon cancer and might have a meaningful effect on the care of patients with colon cancer.

Optimal time of initiating adjuvant chemotherapy after curative surgery in colorectal cancer patients

Purpose

Adjuvant chemotherapy is routinely recommended for locally advanced colorectal cancer (CRC). There are very few data for the optimal starting date of adjuvant chemotherapy after the surgery. This study aimed to evaluate the effectiveness of earlier adoption of adjuvant chemotherapy after curative surgery for stage III CRC.

Methods

In this study, 159 patients with stage III CRC, who had undergone a curative resection, were enrolled retrospectively. Patients were categorized into 3 groups representing different timings to initiate the chemotherapy; less than 2 weeks (group 1), 3 to 4 weeks (group 2), and more than 5 weeks (group 3). The overall survival rate (OS) and the relapse-free survival rate (RFS) were analyzed to evaluate the effectiveness of adjuvant chemotherapy.

Results

The 5-year OSs of the patients were 73.7% in group 1, 67.0% in group 2, and 55.2% in group 3. The 5-year RFSs of the patients were 48.8% in group 1, 64.7% in group 2, and 57.1% in group 3. There were no significant differences in either the OS or the RFS (P = 0.200, P = 0.405).

Conclusion

Starting chemotherapy earlier than 6 weeks after surgery does not show any significant difference. Thus, although adjuvant chemotherapy should preferably begin within 6 weeks, the starting date should not necessarily be hastened, and the patient's general condition should be taken into consideration.