Neoadjuvant chemotherapy (NCT) plus targeted agents versus NCT alone in colorectal liver metastases patients: A systematic review and meta-analysis

[Colorectal cancer liver metastases: current state of the problem, priority treatment approaches]

The review is devoted to the world trends in epidemiology of colorectal cancer and treatment of colorectal cancer liver metastases. The authors analyze the effectiveness of traditional (resection) and modern minimally invasive methods of local destruction (radiofrequency thermoablation, microwave ablation, cryoablation), stereotactic radiotherapy, radiosurgery, targeted therapy and endovascular techniques (chemoinfusion, chemoembolization, radioembolization). It was emphasized that searching for new chemotherapeutic and targeted drugs is one of the reserve ways to improve treatment outcomes in patients with potentially resectable colorectal cancer liver metastases. The possibilities and prospects of liver transplantation as a priority treatment strategy for patients with unresectable bilobar colorectal cancer liver metastases are highlighted.

Colon Cancer, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation-positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org. Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.

Immune phenotype and histopathological growth pattern in patients with colorectal liver metastases

Background

Patients with desmoplastic (angiogenic) histopathological growth pattern (HGP) colorectal liver metastases (CLM) might derive more benefit from bevacizumab-based chemotherapy than those with replacement (non-angiogenic) HGP. This study investigated the association of HGP with the immune phenotype (IP) and clinical outcome after liver resection.

Methods

CLM of patients treated with perioperative bevacizumab-based chemotherapy and liver resection were investigated. Association of HGP and IP with response, recurrence-free survival (RFS) and overall survival (OS) was investigated.

Results

One hundred and eighteen patients (M/F 66/52, median age 62.3 (31.0–80.4) years, median follow-up 32.2 (5.0–92.7) months) were enrolled. The inflamed IP was associated with the desmoplastic HGP. The desmoplastic HGP was associated with better radiological and histological response compared to the replacement HGP, respectively. The replacement HGP was associated with shorter RFS (8.7 versus 16.3 months, HR 2.60, P = 0.001) and OS (36.6 months versus not reached, HR 2.32, P = 0.027), respectively. The non-inflamed IP was associated with shorter RFS (10.8 versus 16.5 months, HR 1.85, P = 0.029). The HGP but not the IP remained significant in multivariable analysis for RFS.

Conclusions

The desmoplastic HGP is associated with the inflamed IP and HGP may be a potential biomarker for adjuvant treatment that includes targeting the immune contexture.

Laparoscopic Parenchymal-Sparing Hepatectomy for Multiple Colorectal Liver Metastases Improves Outcomes and Salvageability: A Propensity Score-Matched Analysis

BACKGROUND

Parenchymal-sparing hepatectomy (PSH) is regarded as the standard of care for colorectal liver metastases (CRLMs) in open surgery. However, the surgical and oncological benefits of laparoscopic PSH compared with laparoscopic major hepatectomy (MH) have not been fully documented.

METHODS

A total of 269 patients who underwent initial laparoscopic liver resections with curative intent for CRLMs between 2004 and 2017 were enrolled. Preoperative patient characteristics and tumor burden were adjusted with propensity score matching, and laparoscopic PSH was compared with laparoscopic MH after matching.

RESULTS

PSH was performed in 148 patients, while MH was performed in 121 patients. After propensity score matching, 82 PSH and 82 MH patients showed similar preoperative characteristics. PSH was associated with lower rates of major postoperative complications compared with MH (6.1 vs. 15.9%; p = 0.046). Recurrence-free survival (RFS) and liver-specific RFS rates were comparable between both groups (p = 0.595 and 0.683). Repeat hepatectomy for liver recurrence was more frequently performed in the PSH group (63.9 vs. 36.4%; p = 0.022), and the PSH group also showed a trend toward a higher overall survival (OS) rate (5-year OS 79.4 vs. 64.3%; p = 0.067). Multivariate analyses revealed that initial MH was one of the risk factors to preclude repeat hepatectomy after liver recurrence (hazard ratio 2.39, p = 0.047).

CONCLUSIONS

Laparoscopic PSH provided surgical and oncological benefits for CRLMs, with less complications, similar recurrence rates, and increased salvageability through repeat hepatectomy, compared with laparoscopic MH. PSH should be the standard approach, even in laparoscopic procedures.

Laparoscopic versus open two-stage hepatectomy for bilobar colorectal liver metastases: A bi-institutional, propensity score-matched study

BACKGROUND

The safety and feasibility of laparoscopic, two-stage hepatectomy for bilobar colorectal liver metastases is poorly evaluated.

METHODS

We reviewed retrospectively 86 consecutive patients who underwent complete two-stage hepatectomy (left lobe clearance as the first stage and standard/extended right hepatectomy as the second stage) for bilobar colorectal liver metastases between 2007 and 2017 in 2 tertiary centers. Short- and long-term outcomes were compared between laparoscopic and open two-stage hepatectomy before and after propensity score matching.

RESULTS

Laparoscopic two-stage hepatectomy was performed in 38 patients and open two-stage hepatectomy in 48. After propensity score matching, 25 laparoscopic and 25 open patients showed similar preoperative characteristics. For the first stage, a laparoscopic approach was associated with lesser hospital stays (4 vs 7.5 days; P < .001). For the second stage, a laparoscopic approach was associated with less blood loss (250 vs 500 mL; P = .040), less postoperative complications (32% vs 60%; P = .047), lesser hospital stays (9 vs 16 days; P = .013), and earlier administration of chemotherapy (1.6 vs 2 months; P = .039). Overall survival, recurrence-free survival, and liver-recurrence-free survival were comparable between the groups (3-year overall survival: 80% vs 54%; P = .154; 2-year recurrence-free survival: 20% vs 18%; P = .200; 2-year liver-recurrence-free survival: 39% vs 33%; P = .269). Although both groups had comparable recurrence patterns, repeat hepatectomies for recurrence were performed more frequently in the laparoscopic two-stage hepatectomy group (56% vs 0%; P = .006).

CONCLUSION

Laparoscopic two-stage hepatectomy for bilobar colorectal liver metastases is safe and feasible with favorable surgical and oncologic outcomes compared to open two-stage hepatectomy.

Preoperative Chemotherapy and Resection Margin Status in Colorectal Liver Metastasis Patients: A Propensity Score–Matched Analysis

In this article, we compared the early and long-term outcomes of patients with metastatic colorectal cancer treated with chemotherapy followed by resection with those of patients undergoing surgery first, focusing our analysis on resection margin status. Patients who underwent liver resection with curative intent for colorectal liver metastases from July 2001 to January 2018 were included in the analysis. Propensity score matching was used to reduce treatment allocation bias. The cohort comprised 164 patients; 117 (71.3%) underwent liver resection first, whereas the remaining 47 (28.7%) had preoperative chemotherapy. After a 1:1 ratio of propensity score matching, 47 patients per group were evaluated. A positive resection margin was found in 13 patients in the surgery-first group (25.5%) versus 4 (8.5%) in the preoperative chemotherapy group ( P = 0.029). Postmatched logistic regression analysis showed that only preoperative chemotherapy was significantly associated with the rate of positive resection margin (odds ratio 0.24, 95% confidence interval 0.07–0.81; P = 0.022). Median follow-up was 41 months (interquartile range 8–69). Cox proportional hazard regression analysis revealed that only positive resection margin was a significant negative prognostic factor (hazard ratio 2.2, 95% CI 1.18–4.11; P = 0.014). Within the preoperative chemotherapy group, median overall survival was 40 months in R0 patients and 10 months in R1 patients ( P = 0.016). Although preoperative chemotherapy in colorectal liver metastasis patients may affect the rate of positive resection margin, its impact on survival seems to be limited. In the present study, the most important prognostic factor was the resection margin status.

The VEGF rise in blood of bevacizumab patients is not based on tumor escape but a host-blockade of VEGF clearance

Vascular endothelial growth factor (VEGF) has become a major target in cancer treatment as it promotes tumor angiogenesis. Therapy with anti-VEGF antibody bevacizumab reportedly induces high levels of circulating VEGF which may potentially contribute to resistance. Based on animal or computational models, mechanisms of VEGF induction by bevacizumab have been proposed but not verified in the clinical setting. Hence, we evaluated sixty patients with colorectal cancer metastases for changes in plasma VEGF during neoadjuvant/conversion and adjuvant chemotherapy with or without bevacizumab. VEGF expression was assessed in tissue sections of liver metastases. The VEGF source was investigated with in vitro cultures of tumor, endothelial cells, fibroblasts and platelets, and potential protein stabilization due to anti-VEGF therapy was addressed. A VEGF rise was observed in blood of bevacizumab patients but not in chemotherapy controls, and VEGF was found to be largely complexed by the antibody. A comparable VEGF increase occurred in the presence (neoadjuvant) and absence of the tumor (adjuvant). Accordingly, VEGF expression in tumor tissue was not determined by bevacizumab treatment. Investigations with isolated cell types did not reveal VEGF production in response to bevacizumab. However, antibody addition to endothelial cultures led to a dose-dependent blockade of VEGF internalization and hence stabilized VEGF in the supernatant. In conclusion, the VEGF rise in cancer patients treated with bevacizumab is not originating from the tumor. The accumulation of primarily host-derived VEGF in circulation can be explained by antibody interference with receptor-mediated endocytosis and protein degradation. Thus, the VEGF increase in response to bevacizumab therapy should not be regarded as a tumor escape mechanism.

The role of neoadjuvant chemotherapy for resectable colorectal liver metastases: a systematic review and meta-analysis

Neoadjuvant chemotherapy is being increasingly accepted as an effective treatment of resectable colorectal liver metastases (CRLM), but it may also damage the hepatic parenchyma. We performed a meta-analysis to compare the outcomes of patients who received neoadjuvant chemotherapy (NEO) prior to hepatic resection with hepatic resection without neoadjuvant chemotherapy (SG). Eligible trials were identified from Embase, PubMed, the Web of Science and the Cochrane library. Hazard ratios (HRs) with a 95% confidence intervals (CIs) were used to measure the pooled effect using a random-effects model. Statistical heterogeneity was detected by I2 test. Sensitivity analyses and publication bias were also assessed. The study outcomes included 3-year, 5-year disease-free and overall survival rate, respectively. Eighteen studies involving 6,254 patients were included. The pooled HRs for 5-year DFS and 5-year OS for NEO in the included studies calculated using the random-effects model were 1.38 (95 % CI; 1.26-1.51, p=0.00; I2=9.6%, p=0.36) and 1.19 (95% CI: 1.02-1.38; p=0.03; I2=49.2%, p=0.03), respectively. For CRLM patients with factors indicating a high risk of recurrence, the pooled HR for 5-year OS of NEO in the included studies calculated using the random-effects model was 0.69 (95% CI: 0.55-0.87; p=0.00; I2=0.0%, p=0.48). These results suggest neoadjuvant chemotherapy improved survival of patients with initially resectable CRLM and a high risk of disease recurrence.

Microscopic biliary and perineural invasion and clinical outcome after neoadjuvant bevacizumab-based chemotherapy and liver resection in patients with colorectal liver metastases

BACKGROUND

The value of microscopic biliary and perineural invasion as prognostic biomarkers in patients with resectable colorectal liver metastases (CLM) who undergo neoadjuvant chemotherapy and liver resection is still unclear. This retrospective study was performed to elucidate this issue.

METHODS

Histologic slides of resected CLM of patients who underwent neoadjuvant bevacizumab-based chemotherapy and liver resection were investigated with respect to biliary and perineural invasion. Presence of invasion was correlated with radiologic and histologic response, recurrence-free survival (RFS) and overall survival (OS).

RESULTS

One hundred forty-one patients were enrolled. There was a significant association between biliary and perineural invasion, respectively (P = 0.001). Moreover, both biliary and perineural invasion were associated with bilobar metastatic spread and higher number of metastases, while perineural invasion was also associated with a higher Fong score. No significant association was found with response. In univariable analysis, biliary and perineural invasion were associated with shorter RFS (median 10.1 vs. 13.5 months, HR 2.09, P = 0.010 and 7.6 vs. 14.0, HR 2.23, P = 0.001, respectively). Biliary invasion was also associated with shorter OS (median 32.8 months vs. not reached, HR 2.78, P = 0.010), however these results did not remain significant in multivariable analysis.

CONCLUSIONS

In patients with resectable colorectal liver metastases undergoing neoadjuvant bevacizumab-based chemotherapy and liver resection, biliary and perineural invasion are associated with higher tumor load but may not be prognostic biomarkers.

Influence of neoadjuvant chemotherapy on resection of primary colorectal liver metastases: A propensity score analysis

BACKGROUND AND OBJECTIVES

There is ongoing debate about whether patients planned for liver resection of colorectal liver metastases (CRLM) benefit from neoadjuvant chemotherapy (NC). Therefore, we performed a retrospective survival analysis of patients with and without NC prior to surgery.

METHODS

Data prospectively collected from 468 consecutive patients were analyzed in a retrospective design. We performed a survival analysis and added propensity score matching (PSM). Univariate and multivariate analysis was performed to determine independent prognostic risk factors.

RESULTS

NC was performed in 145/468 patients. NC did not have a significant influence on overall survival (OS) either before or after PSM. Patients receiving NC showed increased complication rates, especially concerning non-surgical complications after primary resection (P = 0.025) of CRLM. Multivariate analysis before and after PSM revealed that the Memorial Sloan Kettering Cancer Center (MSKCC) score and CEA values are strong predictors for OS in patients with CRLM.

CONCLUSIONS

NC was not associated with increased OS in patients suffering from CRLM. Additionally, potentially harmful chemotherapy prior to surgery increases the risk of postoperative complications in these patients.