Early response evaluation during preoperative chemotherapy for colorectal liver metastases: Combined size and morphology-based criteria predict pathological response and survival after resection

Treatment response assessment to chemotherapy with bevacizumab for colorectal liver metastasis by contrast-enhanced ultrasound

Background

Though contrast-enhanced ultrasound (CEUS) perfusion parameters have been approved to be potential indicators for response to chemotherapy in solid tumors, their ability in assessment of colorectal liver metastasis (CRLM) to chemotherapy with bevacizumab (Bev) has rarely been investigated.

Methods

From March 2021 to May 2022, 115 consecutive CRLM patients with CEUS pre- and post-2 months' chemotherapy with Bev were prospectively enrolled. One target lesion per patient underwent CEUS quantitative analysis with SonoLiver software. Rise time, time-to-peak, mean transit time, maximal intensity (IMAX), and area under the time-intensity curve (AUC) were assessed with region of interest (ROI) selected on whole lesion, lesion periphery, and internal lesion, respectively. The reduction and ratio of post- to pre-treatment in parameters were investigated in development cohort (n=89) and validated in internal validation cohort (n=26) according to the chronological order.

Results

With modified Response Evaluation Criteria in Solid Tumor as reference, 48, 14 responders and 41, 12 non-responders were included in development and validation cohort, respectively. Significantly smaller values of IMAX and AUC on ROIwhole, ROIperipheral, and ROIinternal, were observed post-treatment in development cohort (all P<0.05). In predicting treatment response, the influence of ROI selection was observed when using ∆IMAX and ∆AUC, while no influence was observed using ratios. Areas under the receiver operating characteristic curve (AUROCs) for ∆IMAX and ∆AUC on ROIperipheral were 0.939 (0.867-0.979), 0.951 (0.883-0.985), and 0.917 (0.740-0.988), 0.923 (0.748-0.990) in development and validation cohort, respectively. For ratios of IMAX and AUC, AUROCs were 0.976 (0.919-0.997), 0.938 (0.865-0.978), and 0.899 (0.717-0.982), 0.982 (0.836-1.000) in development and validation cohort, respectively.

Conclusions

IMAX and AUC showed significant reductions in responders, and different analyses ROIs influence the performance of ∆IMAX and ∆AUC in response assessment. Parameters derived from ROI peripheral exhibited the most promising results in predicting treatment response.

A machine learning model for colorectal liver metastasis post-hepatectomy prognostications

Background

Currently, surgical resection is the mainstay for colorectal liver metastases (CRLM) management and the only potentially curative treatment modality. Prognostication tools can support patient selection for surgical resection to maximize therapeutic benefit. This study aimed to develop a survival prediction model using machine learning based on a multicenter patient sample in Hong Kong.

Methods

Patients who underwent hepatectomy for CRLM between 1 January 2009 and 31 December 2018 in four hospitals in Hong Kong were included in the study. Survival analysis was performed using Cox proportional hazards (CPH). A stepwise selection on Cox multivariable models with Least Absolute Shrinkage and Selection Operator (LASSO) regression was applied to a multiply-imputed dataset to build a prediction model. The model was validated in the validation set, and its performance was compared with that of Fong Clinical Risk Score (CRS) using concordance index.

Results

A total of 572 patients were included with a median follow-up of 3.6 years. The full models for overall survival (OS) and recurrence-free survival (RFS) consist of the same 8 established and novel variables, namely colorectal cancer nodal stage, CRLM neoadjuvant treatment, Charlson Comorbidity Score, pre-hepatectomy bilirubin and carcinoembryonic antigen (CEA) levels, CRLM largest tumor diameter, extrahepatic metastasis detected on positron emission-tomography (PET)-scan as well as KRAS status. Our CRLM Machine-learning Algorithm Prognostication model (CMAP) demonstrated better ability to predict OS (C-index =0.651), compared with the Fong CRS for 1-year (C-index =0.571) and 5-year OS (C-index =0.574). It also achieved a C-index of 0.651 for RFS.

Conclusions

We present a promising machine learning algorithm to individualize prognostications for patients following resection of CRLM with good discriminative ability.

Long-Term Outcomes of Perioperative Versus Neoadjuvant Chemotherapy for Resectable Colorectal Liver Metastases: An International Multicentre Propensity-Score Matched Analysis with Stratification by Contemporary Risk-Scoring

BACKGROUND

There is still debate regarding the principal role and ideal timing of perioperative chemotherapy (CTx) for patients with upfront resectable colorectal liver metastases (CRLM). This study assesses long-term oncological outcomes in patients receiving neoadjuvant CTx only versus those receiving neoadjuvant combined with adjuvant therapy (perioperative CTx).

METHODS

International multicentre retrospective analysis of patients with CRLM undergoing liver resection between 2010 and 2015. Characteristics and outcomes were compared before and after propensity score matching (PSM). Primary endpoints were long-term oncological outcomes, such as recurrence-free survival (RFS) and overall survival (OS). Furthermore, stratification by the tumour burden score (TBS) was applied.

RESULTS

Of 967 patients undergoing hepatectomy, 252 were analysed, with a median follow-up of 45 months. The unmatched comparison revealed a bias towards patients with neoadjuvant CTx presenting with more high-risk patients (p = 0.045) and experiencing increased postoperative complications ≥Clavien-Dindo III (20.9% vs. 8%, p = 0.003). Multivariable analysis showed that perioperative CTx was associated with significantly improved RFS (hazard ratio [HR] 0.579, 95% confidence interval [CI] 0.420-0.800, p = 0.001) and OS (HR 0.579, 95% CI 0.403-0.834, p = 0.003). After PSM (n = 180 patients), the two groups were comparable regarding baseline characteristics. The perioperative CTx group presented with a significantly prolonged RFS (HR 0.53, 95% CI 0.37-0.76, p = 0.007) and OS (HR 0.58, 95% CI 0.38-0.87, p = 0.010) in both low and high TBS patients.

CONCLUSIONS

When patients after resection of CRLM are able to tolerate additional postoperative CTx, a perioperative strategy demonstrates increased RFS and OS in comparison with neoadjuvant CTx only in both low and high-risk situations.

Interobserver Variability in CT-based Morphologic Tumor Response Assessment of Colorectal Liver Metastases

Purpose To evaluate interobserver variability in the morphologic tumor response assessment of colorectal liver metastases (CRLM) managed with systemic therapy and to assess the relation of morphologic response with gene mutation status, targeted therapy, and Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 measurements. Materials and Methods Participants with initially unresectable CRLM receiving different systemic therapy regimens from the randomized, controlled CAIRO5 trial (NCT02162563) were included in this prospective imaging study. Three radiologists independently assessed morphologic tumor response on baseline and first follow-up CT scans according to previously published criteria. Two additional radiologists evaluated disagreement cases. Interobserver agreement was calculated by using Fleiss κ. On the basis of the majority of individual radiologic assessments, the final morphologic tumor response was determined. Finally, the relation of morphologic tumor response and clinical prognostic parameters was assessed. Results In total, 153 participants (median age, 63 years [IQR, 56-71]; 101 men) with 306 CT scans comprising 2192 CRLM were included. Morphologic assessment performed by the three radiologists yielded 86 (56%) agreement cases and 67 (44%) disagreement cases (including four major disagreement cases). Overall interobserver agreement between the panel radiologists on morphology groups and morphologic response categories was moderate (κ = 0.53, 95% CI: 0.48, 0.58 and κ = 0.54, 95% CI: 0.47, 0.60). Optimal morphologic response was particularly observed in patients treated with bevacizumab (P = .001) and in patients with RAS/BRAF mutation (P = .04). No evidence of a relationship between RECIST 1.1 and morphologic response was found (P = .61). Conclusion Morphologic tumor response assessment following systemic therapy in participants with CRLM demonstrated considerable interobserver variability. Keywords: Tumor Response, Observer Performance, CT, Liver, Metastases, Oncology, Abdomen/Gastrointestinal Clinical trial registration no. NCT02162563 Supplemental material is available for this article. © RSNA, 2022.

The management of colorectal liver metastases amenable of surgical resection: How to shape treatment strategies according to clinical, radiological, pathological and molecular features

Metastatic colorectal cancer (mCRC) patients have poor chances of long term survival, being < 15% of them still alive after 5 years from diagnosis. Nonetheless, patients with colorectal liver metastases (CRLM) may be eligible for metastases resection thus being able to achieve long-term disease remission and survival. The likelihood for patients with CRLM of being or becoming eligible for liver metastasectomy is increasing, thanks to the evolution of surgical techniques, the availability of active systemic treatments and the widespread diffusion of experienced multidisciplinary boards to manage these patients. However, disease relapse after liver surgery is common and occurs in two-thirds of resected patients. Therefore, adequate radiological staging and risk stratification is crucial for the optimal selection of patients candidate to surgery in order to maximize the benefit-risk ratio of liver metastasectomy and to individualize the treatment strategy. Based on the multidimensional assessment, three possible approaches are available: upfront liver surgery followed by adjuvant chemotherapy, perioperative chemotherapy preceding and following liver surgery, and an upfront systemic treatment including chemotherapy plus a targeted agent, both chosen according to patients' and tumours' characteristics, then followed by liver surgery if indicated. In this review, we describe the most important factors impacting the therapeutic choices in patients with resectable and potentially resectable CRLM, and we discuss the most promising factors that may reshape the future decision-making process of these patients.

Early tumor shrinkage and response assessment according to mRECIST predict overall survival in hepatocellular carcinoma patients under sorafenib

Background

The aim of this study was to explore the relationship between follow-up imaging characteristics and overall survival (OS) in advanced hepatocellular carcinoma (HCC) patients under sorafenib treatment.

Methods

Associations between OS and objective response (OR) by mRECIST or early tumor shrinkage (ETS; ≥20% reduction in enhancing tumor diameter at the first follow-up imaging) were analyzed in HCC patients treated with sorafenib within a multicenter phase II trial (SORAMIC). 115 patients were included in this substudy. The relationship between survival and OR or ETS were explored. Landmark analyses were performed according to OR at fixed time points. Cox proportional hazards models with OR and ETS as a time-dependent covariate were used to compare survival with factors known to influence OS.

Results

The OR rate was 29.5%. Responders had significantly better OS than non-responders (median 30.3 vs. 11.4 months; HR, 0.38 [95% CI, 0.22–0.63], p < 0.001), and longer progression-free survival (PFS; median 10.1 vs. 4.3 months, p = 0.015). Patients with ETS ≥ 20% had longer OS (median 22.1 vs. 11.4 months, p = 0.002) and PFS (median 8.0 vs. 4.3 months, p = 0.034) than patients with ETS < 20%. Besides OR and ETS, male gender, lower bilirubin and ALBI grade were associated with improved OS in univariate analysis. Separate models of multivariable analysis confirmed OR and ETS as independent predictors of OS.

Conclusion

OR according to mRECIST and ETS in patients receiving sorafenib treatment are independent prognostic factors for OS. These parameters can be used for assessment of treatment benefit and optimal treatment sequencing in patients with advanced HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40644-021-00439-x.

The Prognostic Value of Total Tumor Volume Response Compared With RECIST1.1 in Patients With Initially Unresectable Colorectal Liver Metastases Undergoing Systemic Treatment

Objectives

Compare total tumor volume (TTV) response after systemic treatment to Response Evaluation Criteria in Solid Tumors (RECIST1.1) and assess the prognostic value of TTV change and RECIST1.1 for recurrence-free survival (RFS) in patients with colorectal liver-only metastases (CRLM).

Background

RECIST1.1 provides unidimensional criteria to evaluate tumor response to systemic therapy. Those criteria are accepted worldwide but are limited by interobserver variability and ignore potentially valuable information about TTV.

Methods

Patients with initially unresectable CRLM receiving systemic treatment from the randomized, controlled CAIRO5 trial (NCT02162563) were included. TTV response was assessed using software specifically developed together with SAS analytics. Baseline and follow-up computed tomography (CT) scans were used to calculate RECIST1.1 and TTV response to systemic therapy. Different thresholds (10%, 20%, 40%) were used to define response of TTV as no standard currently exists. RFS was assessed in a subgroup of patients with secondarily resectable CRLM after induction treatment.

Results

A total of 420 CT scans comprising 7820 CRLM in 210 patients were evaluated. In 30% to 50% (depending on chosen TTV threshold) of patients, discordance was observed between RECIST1.1 and TTV change. A TTV decrease of >40% was observed in 47 (22%) patients who had stable disease according to RECIST1.1. In 118 patients with secondarily resectable CRLM, RFS was shorter for patients with less than 10% TTV decrease compared with patients with more than 10% TTV decrease (P = 0.015), while RECIST1.1 was not prognostic (P = 0.821).

Conclusions

TTV response assessment shows prognostic potential in the evaluation of systemic therapy response in patients with CRLM.

Assessing prognostic value of early tumor shrinkage and depth of response in first-line therapy for patients with advanced unresectable pancreatic cancer

Background

The prognostic potential of early tumor shrinkage (ETS) and depth of response (DpR) in pancreatic cancer (PC) is unclear. Here, we recruited 90 patients with recurrent and metastatic PC (RMPC) who had received chemotherapy as first-line therapy to assess the prognostic potential of these markers.

Methods

ETS is characterized as a ≥ 20% depletion in the sum-of-the-longest-diameters (SLD) of measurable tumor lesions at 6–12 weeks than the baseline. DpR is the maximum shrinkage (%) from the baseline to nadir. We evaluated corrections in ETS and DpR with survival.

Results

Of the 63 patients in which ETS assessment was possible, 21 (33.3%) achieved ETS. We found a significant association between the incidence of ETS and an improved rate of progression-free survival (PFS; 6.5 vs. 2.2 months; p < 0.001) and overall survival (OS; 12.1 vs. 6.0 months; p = 0.014). The median value of DpR was − 23.66%. DpR was also related to improved PFS (9.3 vs. 3.1 months; p < 0.001) and OS (18.2 vs. 7.3 months; p < 0.001). Patients who had distant metastasis, not local recurrence, with ETS showed markedly better outcomes. In a multivariate model, both ETS and DpR were independent predictors of OS in the whole population.

Conclusions

ETS and DpR may predict favorable outcomes for RMPC patients who had received chemotherapy as first-line therapy, independent of the agents used. Further studies on the exploratory analyses of the optimum ETS cut-off value in recurrent PC patients to predict favorable clinical outcomes are required.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01870-x.

Association of tumor size with prognosis in colon cancer: A Surveillance, Epidemiology, and End Results (SEER) database analysis

BACKGROUND

Thus far, the association of tumor size with prognosis in colon cancer has not been considered and has remained unclear. This study, therefore, aimed to investigate the association between tumor size as a continuous variable and prognosis in colon cancer using Cox models with restricted cubic splines.

METHODS

Using the Surveillance, Epidemiology, and End Results database, we selected 128,369 patients with colon cancer who underwent surgery. Overall survival and colon cancer-specific survival were separately analyzed, and tumor size was separately evaluated as a continuous variable and a categorical variable. To investigate the relationship after adjusting for covariates, we used the proportional hazards models. The restricted cubic splines model was used to determine the presence of nonlinear or linear association and flexibly visualize the association.

RESULTS

The adjusted covariate model showed that the hazard ratio of colon cancer rapidly increased with a tumor size of 4 cm and slowly increased with a tumor size larger than 4 cm. When tumor size was analyzed as a categorical variable, the multivariable-adjusted model demonstrated a nearly linear relationship between tumor size and hazard ratio regardless of overall survival or cancer-specific survival, and the hazard ratio of group 5 (4.1-5 cm) was nearly a turning point. Subgroup analysis with respect to lymph node metastasis showed that the relationship between tumor size and prognosis in colon cancer was evident in lymph node metastasis.

CONCLUSION

There was a strong negative relationship between tumor size and prognosis in colon cancer. However, when tumor size was less than 4 cm, the relationship between tumor size and prognosis was steep compared with that when tumor size was larger than 4 cm, especially in lymph node metastasis.

Early response evaluation during preoperative chemotherapy for colorectal liver metastases: Combined size and morphology-based criteria predict pathological response and survival after resection

BACKGROUND

Short treatment-duration with early restaging is crucial to avoid liver injury after preoperative chemotherapy (preopCTX) for colorectal liver metastases (CRLM). Response evaluation according to response evaluation criteria in solid tumors (RECIST) criteria implies several limitations. Early tumor shrinkage (ETS; ≥20% size reduction <6-12 weeks) or morphological criteria (MC) may better predict oncological outcome.

METHODS

In patients undergoing resection after preopCTX between 2003-2017 pathological and radiological response was reassessed according to Blazer classification, ETS, MC, and RECIST within 90 days and correlated with survival.

RESULTS

Seventy-two patients were included, with a median of two (1-10) liver lesions, 53% bilobar involvement, and 7% extrahepatic disease. PreopCTX was applied for 3 months in median (1-6). During restaging after a median of 62 days, presence of ETS was associated with improved median overall survival (OS; 57.1 vs 33.7 months; P = .010) and disease-free survival (16 vs 7.2 months; P = .025). MC significantly correlated with major pathological response (P = .021). When combining ETS with optimal MC, presence of one or both factors was associated with pathological response (61.5% and 92.3%; P = .044) and OS in log-rank (P = .011), and multivariable analysis (hazard ratio [HR] 0.41; 95% confidence interval [CI], 0.19-0.90 and HR 0.32; 95%CI, 0.11-0.97).

CONCLUSION

Response-grading by combined ETS/MC criteria less than 90 days after preopCTX initiation predicts pathological response and postoperative survival in CRLM.