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

Colon cancer: the 2023 Korean clinical practice guidelines for diagnosis and treatment

Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients' values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

Neoadjuvant chemotherapy versus upfront surgery as the initial treatment for patients with resectable, synchronous colorectal cancer liver metastases

BACKGROUND

Although perioperative chemotherapy has been the standard treatment for colorectal cancer with resectable liver metastases (CRLM), studies that have compared neoadjuvant chemotherapy (NAC) and upfront surgery, especially in the setting of synchronous metastases are rare.

METHODS

We compared perioperative outcomes, overall survival (OS) and overall survival after recurrence (rOS) in a retrospective study of 281 total and 104 propensity score-matched (PSM) patients who underwent curative resection, with or without NAC, for synchronous CRLM, from 2006 to 2017. A Cox regression model was developed for OS.

RESULTS

After PSM, 52 NAC and 52 upfront surgery patients with similar baseline characteristics were compared. Postoperative morbidity, mortality, and 5-year OS rate (NAC: 78.9%, surgery: 64.0%; p = 0.102) were similar between groups; however, the NAC group had better rOS (NAC: 67.3%, surgery: 31.5%; p = 0.049). Initial cancer stage (T4, N1-2), poorly differentiated histology, and >1 hepatic metastases were independent predictors of worse OS. Based on these factors, patients were divided into low-risk (≤1 risk factor, n = 115) and high-risk (≥2 risk factors, n = 166) groups. For high-risk patients, NAC yielded better OS than upfront surgery (NAC: 74.5%, surgery: 53.2%; p = 0.024).

CONCLUSIONS

Although NAC and upfront surgery-treated patients had similar perioperative outcomes and OS, better postrecurrence survival was shown in patients with NAC. In addition, NAC may benefit patients with worse prognoses; therefore, physicians should consider patient disease risk before initiating treatment to identify patients who are most likely to benefit from chemotherapy.

Neoadjuvant Chemotherapy Followed by Radiofrequency Ablation May Be a New Treatment Modality for Colorectal Liver Metastasis: A Propensity Score Matching Comparative Study

Background: Most colorectal liver metastases (CRLM) are not candidates for liver resection. Radiofrequency ablation (RFA) plays a key role in selected CRLM patients. Neoadjuvant chemotherapy (NAC) followed by liver resection has been widely used for resectable CRLM. Whether NAC followed by radiofrequency ablation (RFA) can achieve a similar prognosis to NAC followed by hepatectomy remains is unclear. The present study aimed to provide a new treatment modality for CRLM patients. Methods: This comparative retrospective research selected CRLM patients from 2009 to 2022. They were divided into NAC + RFA group and NAC + hepatectomy group. The propensity score matching (PSM) was used to reduce bias. We used multivariate cox proportional hazards regression analysis to explore independent factors affecting prognosis. The primary study endpoint was the difference in the progression-free survival (PFS) between the two groups. Results: A total of 190 locally curable CRLM patients were in line with the inclusion criteria. A slight bias was detected in the comparison of basic clinical characteristics between the two groups. RFA showed a significant advantage in the length of hospital stay (median; 2 days vs. 7 days; p < 0.001). The 1- and 3-year PFS in the liver resection and the RFA groups was 57.4% vs. 86.9% (p < 0.001) and 38.8% vs. 55.3% (p = 0.035), respectively. The 1-year and 3-year OS in the liver resection and RFA groups was 100% vs. 96.7% (p = 0.191) and 73.8% vs. 73.6% (p = 0.660), respectively. Conclusions: NAC followed by RFA has rapid postoperative recovery, fewer complications, and better prognosis.

Survival Study: International Multicentric Minimally Invasive Liver Resection for Colorectal Liver Metastases (SIMMILR-2)

Introduction: Study: International Multicentric Minimally Invasive Liver Resection for Colorectal Liver Metastases (SIMMILR-CRLM) was a propensity score matched (PSM) study that reported short-term outcomes of patients with CRLM who met the Milan criteria and underwent either open (OLR), laparoscopic (LLR) or robotic liver resection (RLR). This study, designated as SIMMILR-2, reports the long-term outcomes from that initial study, now referred to as SIMMILR-1. Methods: Data regarding neoadjuvant chemotherapeutic (NC) and neoadjuvant biological (NB) treatments received were collected, and Kaplan−Meier curves reporting the 5-year overall (OS) and recurrence-free survival (RFS) for OLR, LLR and RLR were created for patients who presented with synchronous lesions only, as there was insufficient follow-up for patients with metachronous lesions. Results: A total of 73% of patients received NC and 38% received NB in the OLR group compared to 70% and 28% in the LLR group, respectively (p = 0.5 and p = 0.08). A total of 82% of patients received NC and 40% received NB in the OLR group compared to 86% and 32% in the RLR group, respectively (p > 0.05). A total of 71% of patients received NC and 53% received NB in the LLR group compared to 71% and 47% in the RLR group, respectively (p > 0.05). OS at 5 years was 34.8% after OLR compared to 37.1% after LLR (p = 0.4), 34.3% after OLR compared to 46.9% after RLR (p = 0.4) and 30.3% after LLR compared to 46.9% after RLR (p = 0.9). RFS at 5 years was 12.1% after OLR compared to 20.7% after LLR (p = 0.6), 33.3% after OLR compared to 26.3% after RLR (p = 0.6) and 22.7% after LLR compared to 34.6% after RLR (p = 0.6). Conclusions: When comparing OLR, LLR and RLR, the OS and RFS were all similar after utilization of the Milan criteria and PSM. Biological agents tended to be utilized more in the OLR group when compared to the LLR group, suggesting that highly aggressive tumors are still managed through an open approach.

Effect of tumour size ratio on liver recurrence-free survival of patients undergoing hepatic resection for colorectal liver metastases

Background

The study aimed to assess the impact of size differences of multiple liver metastases on liver recurrence-free survival (RFS) in patients undergoing hepatic resection for colorectal liver metastases (CRLMs).

Methods

Overall, 147 patients with CRLMs who underwent hepatic resection between January 2010 and December 2016 were retrospectively analysed. Tumour size ratio (TSR) was defined as the maximum diameter of the largest liver lesion over the maximum diameter of the smallest liver lesion. The univariate and multivariate analyses were performed to determine independent prognostic risk factors. The prognostic value of the TSR was further explored in each Tumour Burden Score (TBS) zone. Log-rank survival analyses were used to compare liver RFS in the new clinical score and the Fong clinical score.

Results

Based on the TSR, patients were classified into three groups: TSR < 2, 2 ≤ TSR < 4, and TSR ≥ 4. According to the multivariate analysis, TSR of 2–4 (hazard ratio [HR], 2.580; 95% confidence interval [CI] 1.543–4.312; P < 0.001) and TSR < 2 (HR, 4.435; 95% CI 2.499–7.872; P < 0.001) were associated with worse liver RFS. As TSR decreased, liver RFS worsened. TSR could further stratify patients in zones 1 and 2 into different risk groups according to the TBS criteria (zone 1: median liver RFS, 3.2 and 8.9 months for groups 1 and 2, respectively, P = 0.003; zone 2: median liver RFS, 3.5, 5.0, and 10.9 months for groups 1, 2, and 3, respectively, P < 0.05). The predictive ability of the new clinical score, which includes TSR, was superior to that of the Fong clinical score.

Conclusions

TSR, as a prognostic tool, could accurately assess the effect of size differences across multiple liver metastases on liver RFS in patients undergoing hepatectomy for CRLMs.

Trial registration

Retrospectively registered

Neoadjuvant Chemotherapy Followed by Radiofrequency Ablation Prolongs Survival for Ablatable Colorectal Liver Metastasis: A Propensity Score Matching Comparative Study

Background

Typically, colorectal liver metastasis (CRLM) is not a candidate for hepatectomy. Radiofrequency ablation (RFA) plays a critical role in unresectable CRLM patients. Nevertheless, high local tumor progression (LTP) and distant metastasis limit the development and further adoption and use of RFA. Neoadjuvant chemotherapy (NAC) has been widely used in resectable CRLM and is recommended by the guidelines. There are no studies on whether NAC can improve the prognosis in ablatable CRLM patients. The present study aimed to determine the feasibility and effectiveness of RFA plus NAC.

Methods

This retrospective cohort included CRLM patients from Zhejiang Cancer Hospital records, who received RFA from January 2009 to June 2020 and were divided into two groups according to the presence or absence of NAC. The Kaplan–Meier method was used to evaluate the 3-year local tumor progression-free survival (LTPFS), progression-free survival (PFS), and overall survival (OS) of the two groups. The propensity score matching was used to reduce bias when assessing survival. Multivariate Cox proportional hazards regression analysis was used to study the independent factors affecting LTPFS, PFS, and OS.

Results

A total of 149 CRLM patients (88 in the RFA alone group and 61 in the plus NAC group) fulfilled the inclusion criteria. Post-RFA complications were 3.4% in the RFA alone group and 16.4% in the plus NAC group. The 3-year LTPFS, PFS, and OS of the RFA only group were 60.9%, 17.7%, and 46.2%, respectively. The 3-year LTPF, PFS, and OS of the plus NAC group were 84.9%, 46.0%, and 73.6%, respectively. In the 29 pairs of propensity score matching cohorts, the 3-year LTPFS, PFS, and OS in the plus NAC group were longer than those in the RFA group (P < 0.05). NAC was an independent protective factor for LTPFS, PFS, and OS (P < 0.05).

Conclusions

For ablatable CRLM patients, RFA plus NAC obtained a better prognosis than RFA alone. Based on the current results, the application of NAC before RFA may become the standard treatment.

Prognostic impact of neoadjuvant chemotherapy in patients with synchronous colorectal liver metastasis: A propensity score matching comparative study

BACKGROUND

Synchronous colorectal liver metastasis (SCRLM) is at an advanced tumor stage and requires multidisciplinary treatments. Neoadjuvant chemotherapy (NAC) is thought to be an effective treatment modality, but its prognostic impact is still unclear.

MATERIALS AND METHODS

Patients with resectable SCRLM presented to eight university hospitals between 2007 and 2017 were retrospectively reviewed. Propensity score matching (PSM) was performed to adjust baseline characteristics between patients who received NAC with those who underwent up-front hepatectomy. The prognostic impact of NAC was then evaluated.

RESULTS

The cohort comprised of 320 patients: 151 patients received NAC and the remaining 169 patients underwent up-front hepatectomy. After a 1:1 ratio of PSM, 102 patients per group were selected. Within the PSM cohort, 66% patients had multiple liver tumors, with 15% having five or more liver tumors. The median survival (95% confidence interval) periods for patients with and without NAC in the PSM cohort were 88.5 (68.4 - not reached) and 84.2 (52.1 - not reached) months, respectively (P = 0.51). On multivariate analysis, the postoperative events in these patients including operative complications and use of adjuvant chemotherapy after hepatectomy were prognostic factors with hazards (95% confidence interval) being 1.88 (1.18-2.98) and 0.65 (0.42-1.01), respectively.

CONCLUSION

This PSM study was restricted to patients with SCRLM and relatively advanced tumor stagings. NAC did not show any significant prognostic impact. While operative complications had a significant prognostic impact, use of adjuvant chemotherapy after hepatectomy had only a marginal prognostic impact. Reconsideration of indications for NAC is needed.

Neoadjuvant chemotherapy for patients with resectable colorectal cancer liver metastases: A systematic review and meta-analysis

BACKGROUND

In recent years, neoadjuvant chemotherapy (NAC) has been increasingly used in patients with resectable colorectal liver metastases. However, the efficacy and safety of NAC in the treatment of resectable colorectal liver metastases (CRLM) are still controversial.

AIM

To assess the efficacy and application value of NAC in patients with resectable CRLM.

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library from inception to December 2020 to collect clinical studies comparing NAC with non-NAC. Data processing and statistical analyses were performed using Stata V.15.0 and Review Manager 5.0 software.

RESULTS

In total, 32 studies involving 11236 patients were included in this analysis. We divided the patients into two groups, the NAC group (that received neoadjuvant chemotherapy) and the non-NAC group (that received no neoadjuvant chemotherapy). The meta-analysis outcome showed a statistically significant difference in the 5-year overall survival and 5-year disease-free survival between the two groups. The hazard ratio (HR) and 95% confidence interval (CI) were HR = 0.49, 95%CI: 0.39-0.61, P = 0.000 and HR = 0.48 95%CI: 0.36-0.63, P = 0.000. The duration of surgery in the NAC group was longer than that of the non-NAC group [standardized mean difference (SMD) = 0.41, 95%CI: 0.01-0.82, P = 0.044)]. The meta-analysis showed that the number of liver metastases in the NAC group was significantly higher than that in the non-NAC group (SMD = 0.73, 95%CI: 0.02-1.43, P = 0.043). The lymph node metastasis in the NAC group was significantly higher than that in the non-NAC group (SMD = 1.24, 95%CI: 1.07-1.43, P = 0.004).

CONCLUSION

We found that NAC could improve the long-term prognosis of patients with resectable CRLM. At the same time, the NAC group did not increase the risk of any adverse event compared to the non-NAC group.

A Prognostic Scoring System to Predict Survival Outcome of Resectable Colorectal Liver Metastases in this Modern Era

BACKGROUND

An individualized treatment decision is based on the accurate evaluation of clinical risk factors and prognosis for resectable colorectal liver metastases. The current study aimed to develop an effective nomogram to predict progression-free survival (PFS) and to design a treatment schedule preoperatively.

METHODS

The study enrolled a primary cohort of 532 patients with resectable colorectal liver metastases (CRLM) who underwent hepatic resection at two institutions and a validation cohort of 237 patients at two additional institutions with resectable CRLM between 1 January 2008 and 31 December 2018. A nomogram was created based on the independent predictors in the multivariable analysis of progression-free survival in the primary cohort. The predictive accuracy and discriminative ability of the nomogram were determined by the concordance index (C-index) and the calibration curve. The score was compared with the current standard Fong score and validated with an external cohort.

RESULTS

The independent risk factors for CRLM patients identified in the multivariable analysis were tumor larger than 5 cm, more than one tumor, RAS mutation, primary lymph node metastasis, and primary tumor located on the right side. All five factors were considered in the nomogram. The C-index of the nomogram for predicting survival was 0.696. With external validation, the C-index of the nomogram for the prediction of the PFS was 0.682, which demonstrated that this model has a good level of discriminative ability. For high-risk patients (score > 16), neoadjuvant chemotherapy improved PFS and overall survival (OS) after hepatic resection.

CONCLUSION

The current nomogram demonstrated an accurate performance in predicting PFS for resectable CRLM patients with liver-limited disease. Based on the current nomogram, high-risk patients (nomogram score > 16) might benefit from neoadjuvant chemotherapy.

Postoperative liver regeneration does not elicit recurrence of colorectal cancer liver metastases after major hepatectomy

BACKGROUND AND OBJECTIVES

Recurrence is a frequent concern in curatively resected CRC liver metastases. Translational research suggests that regeneration upon hepatectomy may also alleviate metastatic recurrence; however, the significance in patients is unclear. We therefore sought to study the effect of liver regeneration on tumor recurrence in patients.

METHODS

In this retrospective cohort study, we included 58 out of 186 potentially eligible patients from our prospectively maintained database of CRC liver metastasis patients between 2001 and 2012 with a median follow-up of 42 months who underwent a formal right or left hemihepatectomy. Liver regeneration in CT volumetry was correlated with recurrence of CRC liver metastases and overall survival.

RESULTS

Liver regeneration increased up to 14 months to 21.0% for left and 122.6% for right hemihepatectomy, respectively, with comparable final volumes. Regeneration was independent of initial tumor stage, number of metastases, and preoperative chemotherapy. Patients with lower liver regeneration showed earlier recurrence of CRC liver metastases (p = 0.006). Overall survival did not differ in patients with weak versus strong liver regeneration.

CONCLUSIONS

The extent of liver regeneration after major hepatectomy does not impede overall survival. Therefore, our data encourage aggressive therapeutical regimes for CRC liver metastases involving major hepatectomies as part of a curative approach.

Comparison of sequential, delayed and simultaneous resection strategies for synchronous colorectal liver metastases

Background

The present study aimed to compare the perioperative safety and long-term survival of patients with synchronous colorectal liver metastases undergoing sequential resection (SeR), delayed resection (DeR) and simultaneous resection (SiR).

Methods

From January 2007 to December 2016, data from patients undergoing surgery at Peking University Cancer Hospital for synchronous colorectal liver metastases were retrospectively collected. The above three different surgical strategies were compared.

Results

A total of 233 cases were included, with 49 in the SeR group, 98 in the DeR group and 86 in the SiR group. The incidence of severe complications was 26.7% in the SiR group, higher than that in the DeR group (11.2%, P = 0.007) and the SeR group (16.3%, P = 0.166). The overall survival at 1 and 3 years in the SeR group (93.9 and 50.1%) was lower than that in the DeR group (94.9 and 64.8%, P = 0.019), but not significantly different from that in the SiR group (93.0 and 55.2%, P = 0.378). Recurrence-free survival at 1 and 3 years in the SeR group (22.4 and 18.4%) was lower than that in the DeR group (43.9 and 24.2%, P = 0.033) but not significantly different from that in the SiR group (31.4 and 19.6%, P = 0.275). Cox multivariate analysis indicated that T4, lymph node-positive primary tumour, liver metastases > 30 mm and SiR (compared with DeR) were correlated with poor prognosis.

Conclusion

Simultaneous resection has a relatively higher incidence of severe complications, and with a staged resection strategy, the prognosis of delayed resection was better than that of sequential resection.

Adjuvant chemotherapy does not provide survival benefits to elderly patients with stage II colon cancer

To date, the effect of adjuvant chemotherapy after curative resection in patients with stage II colon cancer remains controversial. Still, little is known about the effects of adjuvant chemotherapy in patients with stage II colon cancer who are older than 70 years, as most studies did not focus on this population. This study aimed to investigate the oncologic outcomes of elderly patients with stage II colon cancer who underwent curative resection with or without postoperative adjuvant chemotherapy. We retrospectively reviewed medical records of patients older than 70 years who underwent curative resection of stage II primary colon cancer during 2002–2015. Patients were classified into surgery alone (SA) and adjuvant chemotherapy (AC) groups and propensity score-matched at a 1:1 ratio using a logistic regression. The end points were recurrence-free (RFS), cancer-specific (CSS) and overall survival (OS). Of the 623 patients who met the criteria, 145 were assigned to each arm after propensity score matching. The mean ages of the SA and AC groups were 74.3 and 74.0 years, respectively. A log-rank test revealed no significant inter-group differences in RFS (p = 0.202), CSS (p = 0.486) or OS (p = 0.299). In a Cox regression analysis, adjuvant chemotherapy was not found to be an independent factor affecting RFS (p = 0.206), CSS (p = 0.487) or OS (p = 0.301). Adjuvant chemotherapy does not appear to yield survival benefits in elderly patients with stage II colon cancer.

High hepatic expression of PDK4 improves survival upon multimodal treatment of colorectal liver metastases

BACKGROUND

Patients with borderline resectable colorectal liver metastases (CRLM) frequently receive neoadjuvant chemotherapy (NC) to reduce tumour burden, thus making surgical resection feasible. Even though NC can induce severe liver injury, most studies investigating tissue-based prognostic markers focus on tumour tissue. Here, we assessed the prognostic significance of pyruvate-dehydrogenase-kinase isoenzyme 4 (PDK4) within liver tissue of patients undergoing surgical resection due to CRLM.

METHODS

Transcript levels of hypoxia-adaptive genes (such as PDK isoenzymes) were assessed in the tissue of healthy liver, corresponding CRLM, healthy colon mucosa and corresponding tumour. Uni- and multivariate analyses were performed. Responses to chemotherapy upon up- or down-regulation of PDK4 were studied in vitro.

RESULTS

PDK4 expression within healthy liver tissue was associated with increased overall survival and liver function following surgical resection of CRLM. This association was enhanced in patients with NC. PDK4 expression in CRLM tissue did not correlate with overall survival. Up-regulation of PDK4 increased the resistance of hepatocytes and colon cancer cells against chemotherapy-induced toxicity, whereas knockdown of PDK4 enhanced chemotherapy-associated cell damage.

CONCLUSION

Our findings suggest that up-regulated PDK4 expression reduces hepatic chemotherapy-induced oxidative stress and is associated with improved postoperative liver function in patients undergoing multimodal treatment and resection of CRLM.

Prognostic indicators lose their value with repeated resection of colorectal liver metastases

BACKGROUND

The liver is the most common site of colorectal liver metastases (CRLM) and surgical resection improves overall survival in selected patients. Here, we investigate outcomes and relevant prognostic factors after repeated hepatic resections for CRLM.

METHODS

From a prospective database, 578 patients who underwent 788 resections of colorectal liver metastases were included into this study. In total, 169 patients underwent a second and 41 patients had a third operation due to intrahepatic metastatic recurrence. Univariate and multivariate analyses were performed to determine prognostic risk factors.

RESULTS

5-year overall survival was 36.7% (95% CI: 30.2%; 43.2%) and 10-year survival was 20.3% (95% CI: 7.6%; 33.0%) in patients undergoing single resection. In patients undergoing a second or third resection, 5- and 10-year survival rates were 56.6% (95% CI: 45.0%; 68.2%) and 21.9% (95% CI: 6.8%; 37.0%) or 53.2% (95% CI: 32.4%; 74.0%) and 25.4%, respectively. In patients undergoing single resection, established markers (number, size and pattern of CRLM [p = 0.030/0.015/<0.001], R-status [p = 0.001], surgical/medical complications [p = 0.001/0.008], CEA-level [p = 0.001] and Fong-Score [p = 0.02]) were significantly associated with survival. In patients undergoing three resections, the only predictive markers were pT-stage of the primary tumor in univariate analysis (p = 0.013) and metachronous metastasis and medical complications in multivariate analysis (p = 0.001/0.025). The Fong-Score had no predictive value in patients undergoing two (p = 0.08) or three (p = 0.7) resections.

CONCLUSION

Established prognostic indicators are not applicable in patients undergoing repeated CRLM resection. In a highly-selected group of patients, repeated hepatic resections can be performed safely with favorable long-term outcomes.