Nonresponse to pre-operative chemotherapy does not preclude long-term survival after liver resection in patients with colorectal liver metastases

Predicting response to neoadjuvant chemotherapy for colorectal liver metastasis using deep learning on prechemotherapy cross-sectional imaging

BACKGROUND AND OBJECTIVES

Deep learning models (DLMs) are applied across domains of health sciences to generate meaningful predictions. DLMs make use of neural networks to generate predictions from discrete data inputs. This study employs DLM on prechemotherapy cross-sectional imaging to predict patients' response to neoadjuvant chemotherapy.

METHODS

Adult patients with colorectal liver metastasis who underwent surgery after neoadjuvant chemotherapy were included. A DLM was trained on computed tomography images using attention-based multiple-instance learning. A logistic regression model incorporating clinical parameters of the Fong clinical risk score was used for comparison. Both model performances were benchmarked against the Response Evaluation Criteria in Solid Tumors criteria. A receiver operating curve was created and resulting area under the curve (AUC) was determined.

RESULTS

Ninety-five patients were included, with 33,619 images available for study inclusion. Ninety-five percent of patients underwent 5-fluorouracil-based chemotherapy with oxaliplatin and/or irinotecan. Sixty percent of the patients were categorized as chemotherapy responders (30% reduction in tumor diameter). The DLM had an AUC of 0.77. The AUC for the clinical model was 0.41.

CONCLUSIONS

Image-based DLM for prediction of response to neoadjuvant chemotherapy in patients with colorectal cancer liver metastases was superior to a clinical-based model. These results demonstrate potential to identify nonresponders to chemotherapy and guide select patients toward earlier curative resection.

Hepatectomy versus Chemotherapy for Resectable Colorectal Liver Metastases in Progression after Perioperative Chemotherapy: Expanding the Boundaries of the Curative Intent

Disease progression (PD) at neoadjuvant chemotherapy for patients with colorectal liver metastases (CLMs) is considered a contraindication to hepatic resection. Our aim was to estimate the overall survival (OS) in patients undergoing surgery compared with those treated exclusively with chemotherapy in cases of PD. Patients from a single centre with PD were analyzed and subdivided into two groups: hepatectomy (HEP) versus chemotherapy (CHT). An Inverse Probability Weighting (IPW) was run to balance the baseline differences between the two groups. A Cox regression was carried out on identifying factors predicting mortality. From 2010 to 2020, 105 patients in PD to at least one line of chemotherapy were analyzed. Of these, 27 (25.7%) underwent hepatic resection. After a median follow-up of 30 (IQR 14-46) months, 61.9% were dead. The OS values at 1 and 3 years were 54.4 and 10.6% for CHT, and 95 and 46.8% for HEP (p < 0.001). After IPW, two balanced pseudopopulations were obtained: HEP = 85 and CHT = 103. The OS values at 1 and 3 years were 54.4 and 10.6% for CHT, and 97.8 and 49.3% for HEP (HR 0.256, 95%CI: 0.08-0.78, p = 0.033). After IPW, in the multivariate model, surgery resulted in the only protective variable (HR 0.198, 95%CI: 0.08-0.48, p = 0.0016). Our results show that hepatic resection could offer a chance of a longer OS than the prosecution of chemotherapy only in originally resectable patients.

Oncologic aspects of the decision-making process for surgical approach for colorectal liver metastases progressing during chemotherapy

Colorectal cancer represents the third most diagnosed malignancy in the world. The liver is the main site of metastatic disease, affected in 30% of patients with newly diagnosed disease. Complete resection is considered the only potentially curative treatment for colorectal liver metastasis (CRLM), with a 5-year survival rate ranging from 35% to 58%. However, up to 80% of patients have initially unresectable disease, due to extrahepatic disease or bilobar multiple liver nodules. The availability of increasingly effective systemic chemotherapy has contributed to converting patients with initially unresectable liver metastases to resectable disease, improving long-term outcomes, and accessing tumor biology. In recent years, response to preoperative systemic chemotherapy before liver resection has been established as a major prognostic factor. Some studies have demonstrated that patients with regression of hepatic metastases while on chemotherapy have improved outcomes when compared to patients with stabilization or progression of the disease. Even if disease progression during chemotherapy represents an independent negative prognostic factor, some patients may still benefit from surgery, given the role of this modality as the main treatment with curative intent for patients with CRLM. In selected cases, based on size, the number of lesions, and tumor markers, surgery may be offered despite the less favorable prognosis and as an option for non-chemo responders.

Colorectal liver metastases: ADC as an imaging biomarker of tumor behavior and therapeutic response

PURPOSE

To correlate the ADC values of colorectal liver metastases, evaluated before (preADC) and after (postADC) neoadjuvant chemotherapy (ChT), as well as their difference (ΔADC), with the histological tumor regression grade (TRG) and to determine whether the preADC value can be predictive of the lesion ChT response.

METHOD

Twenty-four patients with colorectal liver metastases, who had undergone 3 T-MRI before and after ChT and were subsequently treated by parenchymal-spearing surgery, were retrospectively included. Diffusion-weighted MRI (DW-MRI) was performed using a spin-echo echo-planar sequence with multiple b values, obtaining an ADC map. Fitted ADC values were calculated for each lesion before and after ChT. The maximum diameter of each lesion in both examinations was recorded. Diameter variations and RECIST1.1 criteria were assessed. All MRI findings were histopathologically correlated to TRG of resected liver metastases. Statistical analysis was performed on a per-lesion basis.

RESULTS

A total of 58 colorectal liver metastases were analysed; after ChT, 8 out of 58 lesions disappeared. TRG1, TRG2, TRG3, TRG4 and TRG5 were observed in 6, 12, 12, 13 and 7 lesions, respectively. The preADC values showed a different distribution according to the TRG scores (p = 0.0027), even though the distribution was not linear. The postADC and ΔADC values were significant different based on the TRG system (both p < 0.0001). A significant correlation between the lesion TRG and the evaluation according to RECIST1.1 criteria was observed by a per-lesion analysis (p = 0.0009).

CONCLUSIONS

PostADC and ΔADC could be proposed as reliable biomarkers to assess tumor treatment response after preoperative ChT in patients with colorectal liver metastases.

Comparison of intravoxel incoherent motion imaging, diffusion kurtosis imaging, and conventional DWI in predicting the chemotherapeutic response of colorectal liver metastases

PURPOSE

To assess the usefulness and performance of intravoxel incoherent motion imaging (IVIM) with diffusion kurtosis imaging (DKI) and conventional DWI for predicting the chemotherapeutic response of colorectal liver metastases (CRLMs).

METHOD

A prospective study was conducted. Up to February 2018, forty consecutive patients treated with the standard first-line chemotherapy regimens were enrolled. MRI was performed within 1 week before chemotherapy, as well as 2-3 weeks and 6-8 weeks after chemotherapy. The apparent diffusion coefficient map, IVIM and DKI parameter maps were calculated using a prototype postprocessing software. The response was assessed by the Response Evaluation Criteria in Solid Tumors. The parameters were compared between the responding group (complete and partial response) and the nonresponding group (stable and progressive disease).

RESULTS

A total of 15 responding and 25 nonresponding patients were evaluated. Low baseline ADC, D_slow, and D values (P =  0.001, <0.001, and =0.003, respectively) and a high baseline K value (P =  0.002) were independently associated with a good response to chemotherapy. The combination of all the significant parameters yielded an AUC of 0.867. After treatment, the ADC, D_slow, and D values all showed an upward trend, while the K value showed a decreasing trend, but there were no significant differences (P >  0.05).

CONCLUSION

The study showed that the pretreatment IVIM (D_slow), DKI (D and K), and conventional DWI (ADC) parameters all demonstrated a good diagnostic performance in predicting the chemotherapeutic response of CRLMs.

Response to preoperative chemotherapy: impact of change in total burden score and mutational tumor status on prognosis of patients undergoing resection for colorectal liver metastases

BACKGROUND

Progression of colorectal liver metastasis (CRLM) on preoperative chemotherapy has been associated with a worse prognosis compared with patients who have responsive disease. Defining response can be challenging as traditional criteria largely assess only tumor size.

METHODS

Patients who underwent hepatectomy between 2010 and 2017 were identified using a multi-centric database. This study aimed to define the impact of preoperative chemotherapy response relative to initial tumor burden score (TBS) and determine impact of clinico-pathological variables on overall survival (OS).

RESULTS

Among 784 patients who received preoperative chemotherapy, the regimen was oxaliplatin- (66%) or irinotecan-based (34%). Among patients with a TBS<6 at diagnosis, genetic status was the most important prognostic variable. Patients with a TBS<6, 5-year OS was 55%, 35%, and 0% for patients with KRAS/NRAS/BRAF wild-type, KRAS/NRAS, and BRAF mutations, respectively. Among patients who presented with CRLM with a TBS≥6, only Δ-TBS was prognostically important and patients with a Δ-TBS ≥ -10% had a 5-year OS of 27% compared with 49% for patients with a Δ-TBS < -10%.

CONCLUSIONS

Prognostic stratification of patients with CRLM receiving preoperative chemotherapy should be multi-faceted and include consideration of initial tumor burden, change in tumor burden due to chemotherapy, and tumor genetic status.

Heterogeneous radiological response to neoadjuvant therapy is associated with poor prognosis after resection of colorectal liver metastases

INTRODUCTION

Surgery combined with perioperative chemotherapy has become standard of care in patients with resectable colorectal liver metastases. However, poor outcome is expected for a significant subgroup. The clinical implications of inter-metastatic heterogeneity remain largely unknown. In a prospective, population-based series of patients undergoing resection of multiple colorectal liver metastases, the aim was to investigate the prevalence and prognostic impact of heterogeneous response to neoadjuvant chemotherapy.

MATERIALS AND METHODS

Radiological response to treatment was evaluated in a lesion-specific manner in 2-5 metastases per patient. Change of lesion diameter was evaluated and response/progression was classified according to three different size thresholds; 3, 4 and 5 mm. A heterogeneous response was defined as progression and response of different metastases in the same patient.

RESULTS

In total, 142 patients with 585 liver metastases were examined with the same radiological method (MRI or CT) before and after neoadjuvant treatment. Heterogeneous response to treatment was seen in 16 patients (11%) using the 3 mm size change threshold, and this group had a 5-year cancer-specific survival of 19% compared to 49% for patients with response in all lesions (p = 0.003). Cut-off values of 4-5 mm were less sensitive for detecting a heterogeneous response, but the survival difference was similar and significant.

CONCLUSION

A subgroup of patients with multiple colorectal liver metastases had heterogeneous radiological response to neoadjuvant chemotherapy and poor prognosis. The evaluation of response pattern is easy to perform, feasible in clinical practice and, if validated, a promising biomarker for treatment decisions.

Survival prediction in patients with resectable colorectal liver metastases: Clinical risk scores and tumor response to chemotherapy

Clinical risk scores and response to pre-operative chemotherapy are prognostic factors of colorectal liver metastases. The aim of the present study was to evaluate the effectiveness of combining these factors to predict patient survival and to select patients for curative therapy. The study included 189 patients who underwent hepatectomy following neo-adjuvant chemotherapy, for initially resectable colorectal liver metastases, between January 2005 and December 2015. Patients were stratified into four sub-groups: A1-2, low clinical risk scores with/without a response to pre-operative chemotherapy; and B1-2, high clinical risk scores with or without a response to pre-operative chemotherapy. Treatment and survival data were analysed. Survival was significantly longer in patients with low clinical risk scores and a response to pre-operative chemotherapy; these factors were confirmed as independent prognostic factors by multivariate analysis. Combining clinical risk score and chemotherapy response classification, patient survival was significantly longer for groups A1-2/B1 compared with for group B2, in which only 10.2% of patients were alive after 5 years. Of those with no response to first-line chemotherapy, survival was significantly longer in patients who responded to second-line chemotherapy. A combined clinical risk score and chemotherapy response classification may aid in identifying suitable candidates for potentially curative therapy.

Non-response to preoperative chemotherapy is a contraindication to hepatectomy plus radiofrequency ablation in patients with colorectal liver metastases

The long-term outcome of 228 patients with colorectal liver metastases (CRLM) who underwent preoperative chemotherapy followed by hepatectomy ± RFA were retrospectively analyzed. Stratified by chemotherapy response, patients were divided into responding (n=129) and non-responding groups (n=99). Patients who underwent hepatectomy-RFA had a greater number of metastases (median of 4 vs. 2, p=0.000), a higher incidence of bilobar involvement (66.7% vs. 49.1%, p=0.014) and longer chemotherapy cycles (median of 6 vs. 4, p=0.000). In the responding group, the median overall survival (OS) and recurrence free survival (RFS) of hepatectomy-RFA and the hepatectomy alone subgroups were comparable (38.6 months vs. 43.2 months, p=0.824; 8.2 months vs. 11.4 months, p=0.623). In the non-responding group, the median OS and RFS of patients treated with hepatectomy-RFA were significantly shorter (18.5 months vs. 34.2 months, p=0.000; 5.1 months vs. 5.9 months, p=0.002). RFA was identified as the unfavorable independent factor for both OS (HR=3.60, 95%CI=1.81-7.16, p=0.039) and RFS (HR=1.70, 95%CI=1.00-2.86, p=0.048) in non-responsive patients. Local recurrence rate after hepatectomy-RFA was higher in the non-responding group (48.1% vs. 23.6%, p=0.018). Non-response to preoperative chemotherapy may be a contraindication to hepatectomy-RFA in patients with CRLM.

3T diffusion-weighted MRI in the response assessment of colorectal liver metastases after chemotherapy: Correlation between ADC value and histological tumour regression grading

PURPOSE

The purpose of the study was to correlate the apparent diffusion coefficient (ADC) values of diffusion-weighted MR imaging (DW-MRI) by 3T device with the histological tumour regression grading (TRG) analysis of colorectal liver metastases after preoperative chemotherapy.

MATERIALS AND METHODS

Our study included thirty-five patients with colorectal liver metastases who had undergone MRI by 3T device (GE DISCOVERY MR750; GE Healthcare) after preoperative chemotherapy. DW-MRI was performed using a single-shot spin-echo echo-planar sequence with multiple b-values (0, 150, 500, 1000, 1500s/mm²), thus obtaining an ADC map. For each liver lesion (more than 1cm in diameter) the fitted ADC values were calculated by two radiologists in conference and three ROIs were drawn: around the entire tumour (ADC_e), at the tumour periphery (ADC_p) and at the tumour center (ADC_c). All ADC values were correlated with histopathological findings after surgery. Hepatic metastases were pathologically classified into five groups on the basis of TRG. Statistical analysis was performed on a per-lesion basis utilizing the one-way analysis of variance (ANOVA). This retrospective study was approved by our institutional review board; written informed consent was obtained from all patients.

RESULTS

A total of 106 colorectal liver metastases were included for image analysis. TRG1, TRG2, TRG3, TRG4 and TRG5 were observed in 4, 14, 36, 35 and 17 lesions, respectively. ADC_e and ADC_p values were significantly higher in lesions classified as TRG1 (2.40±0.12×10^-9m²/s and 2.28±0.26×10^-9m²/s, respectively) and as TRG2 (1.40±0.31×10^-9m²/s and 1.44±0.35×10^-9m²/s), compared to TRG3 (1.16±0.13×10^-9m²/s and 1.01±0.18×10^-9m²/s), TRG4 (1.10±0.26×10^-9m²/s and 0.97±0.24×10^-9m²/s), and TRG5 (0.93±0.17×10^-9m²/s and 0.82±0.28×10^-9m²/s). ADC_e, ADC_p and ADC_c values were significantly different in TRG classes (p<0.0001). Statistical correlations were found between the ADC_e, ADC_p, ADC_c values and the TRG classes (Spearman correlation coefficient were -0.568, -0.542 and -0.554, respectively).

CONCLUSION

Our study showed a significant correlation between ADC values of 3T DW-MRI and histological TRG of colorectal liver metastases after preoperative chemotherapy.

BRAZILIAN CONSENSUS FOR MULTIMODAL TREATMENT OF COLORECTAL LIVER METASTASES. MODULE 3: CONTROVERSIES AND UNRESECTABLE METASTASES

In the last module of this consensus, controversial topics were discussed. Management of the disease after progression during first line chemotherapy was the first discussion. Next, the benefits of liver resection in the presence of extra-hepatic disease were debated, as soon as, the best sequence of treatment. Conversion chemotherapy in the presence of unresectable liver disease was also discussed in this module. Lastly, the approach to the unresectable disease was also discussed, focusing in the best chemotherapy regimens and hole of chemo-embolization.

Rebound growth of hepatic colorectal metastases after neo-adjuvant chemotherapy: effect on survival after resection

BACKGROUND

A period of recovery is commonly allowed between completion of chemotherapy for colorectal liver metastases (CRLM) and resection, during which tumour progression may occur. The study-aim is to assess the growth of CRLM in this interval and association with outcome.

METHOD

Data on 146 patients were analysed. Change in tumour size was assessed by comparing size determined by imaging performed on completion of chemotherapy with that determined by examination of the resected specimen, categorised by RECIST criteria.

RESULTS

In the interval before surgery sixteen patients (11%) fulfilled criteria for partial response (PR), 48 (33%) had stable disease (SD) and 82 (56%) had progressive disease (PD). Among patients with PD following chemotherapy the median disease-free survival of patients who initially responded (26 months) was longer than in those who initially had stable disease (7 months) (P = 0.002). No association was noted between rate of tumour growth after completion of chemotherapy and disease-free survival.

CONCLUSION

Change in tumour size after completion of chemotherapy is variable and can be rapid, especially in patients who initially respond to treatment. However, disease-free survival is determined by tumour behaviour during treatment and not by change in size after completion of chemotherapy.

Oncological Outcomes of Major Liver Resection Following Portal Vein Embolization: A Systematic Review and Meta-analysis

BACKGROUND

Preoperative portal vein occlusion with either percutaneous portal vein embolization (PVE) or portal vein ligation is routinely used to induce liver hypertrophy prior to major liver resection in patients with hepatic malignancy. While this increases the future liver remnant, and hence the number of patients suitable for resection, recent evidence suggests that induction of liver hypertrophy preoperatively may promote tumor growth and increase recurrence rates. The aims of this current study were to evaluate the impact of PVE on hepatic recurrence rate and survival in patients with colorectal liver metastases (CRLM).

METHODS

The MEDLINE, EMBASE and Web of Science databases were searched to identify studies assessing the oncological outcomes of patients undergoing major liver resection for CRLM following PVE. Studies comparing patients undergoing one-stage liver resection with or without preoperative PVE were included. The primary outcome was postoperative hepatic recurrence (PHR), while secondary outcomes were 3- and 5-year overall survival (OS).

RESULTS

Of the 2131 studies identified, six non-randomized studies (n = 668) met the eligibility criteria, comparing outcomes of patients undergoing major liver resection with or without PVE (n = 182 and n = 486, respectively). No significant difference was observed in PHR (odds ratio [OR] 0.78; 95 % confidence interval [CI] 0.42-1.44), 3-year OS (OR 0.80; 95 % CI 0.56-1.14) or 5-year OS (OR 1.12; 95 % CI 0.40-3.11).

CONCLUSIONS

PVE does not have any adverse effect on PHR or OS in patients undergoing major liver resection for CRLM. Further studies based on individual patient data are needed to provide definitive answers.

'Liver-first' approach for metastatic colorectal cancer

The liver-first approach was proposed for the first time in 2006 to obtain resectability of stage IV colorectal cancer patients and complete the therapeutic plan. From then some groups have used this new revolutionary approach reporting promising results. Other alternative strategies have been proposed for metastatic patients. The authors reviewed the literature weighing the pros and cons of each strategy proposed to manage these advanced tumor stages. The therapeutic options are analyzed in the light of oncologic problems and evidence. Also problems, questions and perspectives are given. Even if the 'liver-first' approach seems to be a promising strategy, the ideal diagnostic-therapeutic flowchart for metastatic colorectal cancer is still difficult to standardize. The great heterogeneity of this population of patients is one of the main problems. A 'tailored approach' philosophy is necessary to calibrate, in a multidisciplinary setting, a case-by-case choice of therapeutic options.

Diffusion-weighted and hepatobiliary phase gadoxetic acid-enhanced quantitative MR imaging for identification of complete pathologic response in colorectal liver metastases after preoperative chemotherapy

PURPOSE

To evaluate the diagnostic performance of diffusion-weighted imaging (DWI) and gadoxetic acid-enhanced magnetic resonance imaging (MRI) to differentiate colorectal liver metastasis (CRLM) with complete pathologic response from those with incomplete response in patients treated with preoperative chemotherapy.

METHODS

Gadoxetic acid-enhanced liver MRI and DWI were performed after completion of preoperative chemotherapy in patients with CRLM scheduled for liver resection. Metastases were classified as those with complete pathologic response (CR-CRLM) or incomplete response (IR-CRLM) according to postsurgical histopathology. Quantitative analysis was performed on non-contrast-enhanced images and hepatobiliary phase images following gadoxetic acid administration. Apparent diffusion coefficient values (ADC), normalized relative enhancement (NRE), and relative signal intensity difference (RSID) along with their diagnostic measures for detection of CR-CRLM were calculated for all lesions.

RESULTS

In 23 patients, 10 CR-CRLM and 35 IR-CRLM (mean diameter, 21.2 mm) were evaluated. In CR-CRLM, ADC was significantly higher after exclusion of the outliers (p = 0.030); and RSID was significantly lower (p = 0.008). Combined indices range of ADC = 1.25-1.9 × 10(-3) mm(2)/s, NRE = 0-35% and RSID <120 had 60% sensitivity and 100% specificity for detection of CR-CRLM.

CONCLUSION

DWI and gadoxetic acid-enhanced MRI appear promising for the detection of CRLM with complete response to preoperative chemotherapy. This could have significant implications for liver resection planning after preoperative chemotherapy.

Surgical management of hepatic metastases of colorectal cancer

For the 20% of patients with resectable colorectal liver metastases (CRLM), hepatic resection is safe, effective and potentially curative. Factors related to the primary and metastatic tumors individually and in clinical risk-scoring schemes are the best prognostic factors, although it is difficult to define patient groups with resectable, liver-limited CRLM that should be excluded from surgery. Systemic chemotherapy for metastatic colorectal cancer has improved but does not improve overall survival as adjuvant therapy after resection. Conversion to complete resection with systemic and/or hepatic arterial infusion chemotherapy is an appropriate goal for patients with unresectable CRLM.

Portal vein embolization and its effect on tumour progression for colorectal cancer liver metastases

BACKGROUND

The aim of this study was to evaluate the long-term outcomes of patients with colorectal cancer liver metastasis (CRCLM) exhibiting disease progression after portal vein embolization (PVE).

METHODS

Patients with CRCLM requiring PVE before hepatectomy between 2003 and 2014 were included. Clinical variables, and liver and tumour volumes determined by three-dimensional CT volumetry were assessed before and after PVE. Overall and disease-free survival data were obtained. Univariable and multivariable logistic regression analyses were performed to identify predictors of tumour progression after PVE.

RESULTS

Of 141 patients who underwent PVE, 93 (66.0 per cent) had tumour progression and 17 (12.1 per cent) developed new contralateral lesions. Significantly fewer patients had resectable disease in the group with disease progression than among those with stable disease: 43 (46 per cent) of 93 versus 36 (75 per cent) of 48 respectively (P = 0.001). Median survival was similar in patients with and without tumour growth after PVE: 22.5 versus 26.0 months for patients with unresectable tumours (P = 0.706) and 46.2 versus 52.2 months for those with resectable disease (P = 0.953). However, disease-free survival for patients with tumour progression after PVE was shorter than that for patients with stable disease (6.0 versus 20.2 months; P = 0.045). Response to neoadjuvant chemotherapy was the only significant factor associated with tumour progression in multivariable analysis.

CONCLUSION

Tumour progression after PVE did not affect overall survival, but patients with resected tumours who had tumour growth after embolization experienced earlier recurrence. A borderline response to neoadjuvant chemotherapy seemed to be associated with tumour progression after PVE.

Role of neoadjuvant chemotherapy in resectable synchronous colorectal liver metastasis; An international multi-center data analysis using LiverMetSurvey

BACKGROUND AND OBJECTIVES

The use of neo-adjuvant chemotherapy in resectable synchronous liver metastasis is ill defined. The aim of this study was to evaluate neo-adjuvant chemotherapy on outcomes following liver resection for synchronous CLM.

METHODS

An analysis of a multi-centric cohort from the LiverMetSurvey International Registry, who had undergone curative resections for synchronous CLM was undertaken. Patients who received neo-adjuvant chemotherapy prior to liver surgery (group NAS; n = 693) were compared with those treated by surgery alone (group SG; n = 608). Baseline clinicopathological variables were compared. Predictors of overall (OS) and disease free survival (DFS) were subsequently identified.

RESULTS

Clinicopathological comparison of the groups revealed a greater proportion of solitary metastasis in the SG compared to the NAS group (58.8% versus 38.4%; P < 0.001) therefore a separate analysis of solitary versus multi-centric analysis was performed. N-stage (> N1), number of metastasis (> 3), serum CEA (> 5 ng/ml) and no adjuvant chemotherapy independently predicted poorer OS, while N-stage (> N1), serum CEA (> 5 ng/ml) and no adjuvant chemotherapy independently predicted poorer DFS. Neo-adjuvant chemotherapy did not independently affect outcome.

CONCLUSION

We present an analysis of a large multi-center series of the role of neo-adjuvant chemotherapy in resectable CLM and demonstrate no survival advantage in this setting.

[Neoadjuvant chemotherapy or primary surgery for colorectal liver metastases. Pro primary surgery]

Approximately 50 % of patients with colorectal cancer (CRC) develop liver metastases, with the liver being the only site of metastasis in the majority of patients. Liver resection is the standard treatment of CRC liver metastases as it achieves a 5-year survival of 36-51 %. The primary goal in the treatment of non-resectable liver metastases is to achieve resectability by preoperative chemotherapy as even secondary liver resection after down-sizing is associated with improved overall survival. Furthermore, resectability can be increased by two-stage surgical procedures; however, the assessment of resectability varies widely even among experts in the field. In cases of suspected non-resectability patients should therefore be liberally admitted for a second opinion to centers of liver surgery. Perioperative chemotherapy in primarily resectable cases has only demonstrated an improvement in recurrence-free survival in subgroup analyses. Moreover, modern potent chemotherapy regimens increase the surgical morbidity depending on the duration of treatment: the lower the histological response of the metastases and the more treatment cycles are applied, the higher is the parenchymal damage with related surgical morbidity. Therefore, perioperative chemotherapy of resectable liver metastases should be viewed with caution and should not be considered the standard of care.

Assessment of chemotherapy response in colorectal liver metastases in patients undergoing hepatic resection and the correlation to pathologic residual viable tumor

BACKGROUND

The Response Evaluation Criteria in Solid Tumors (RECIST), which evaluates maximum tumor diameter only, is commonly used to determine response to chemotherapy in patients with colorectal liver metastases. Limitations of RECIST include its inability to assess the changes in tumor enhancement. The aim of this study was to assess the correlation of these criteria as well as the modified RECIST (mRECIST) with pathologic tumor response. A novel semi-automated volumetric assessment of tumor size was also investigated.

STUDY DESIGN

A review of a 1,948-patient prospective hepatic database to assess response and pathologic criteria was performed. Patients undergoing preoperative chemotherapy before hepatic resection for colorectal liver metastases were reviewed. Radiographic responses according to RECIST and mRECIST were determined. The percentage of viable tumor cells compared with the total tumor area was determined from the pathologic specimens.

RESULTS

We identified 38 patients with adequate imaging who had undergone anatomic hepatic resection and full pathologic evaluation. The percentages of residual viable tumor in the resected specimens were significantly different across RECIST categories (p = 0.045), but not mRECIST (p = 0.305). For mRECIST, there were improved and significant linear trends for residual viable tumor, necrosis, and necrosis + fibrosis when compared with RECIST (p = 0.056). Neither RECIST nor mRECIST responses were predictive of residual viable tumor burden in regression analyses. A novel semi-automated volumetric assessment of tumor size correlated well with pathologic tumor size.

CONCLUSIONS

Neither RECIST nor mRECIST were predictive of residual viable burden, although the linear trend for mRECIST and residual necrosis + fibrosis compared favorably with RECIST. Continued evaluation for tumor enhancement and standardization of tumor size remain a critical unmet need in patients with solid organ disease.

Selection for hepatic resection of colorectal liver metastases: expert consensus statement

Hepatic resection offers a chance of a cure in selected patients with colorectal liver metastases (CLM). To achieve adequate patient selection and curative surgery, (i) precise assessment of the extent of disease, (ii) sensitive criteria for chemotherapy effect, (iii) adequate decision making in surgical indication and (iv) an optimal surgical approach for pre-treated tumours are required. For assessment of the extent of the disease, contrast-enhanced computed tomography (CT) and/or magnetic resonance imaging (MRI) with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) is recommended depending on the local expertise and availability. Positron emission tomography (PET) and PET/CT may offer additive information in detecting extrahepatic disease. The RECIST criteria are a reasonable method to evaluate the effect of chemotherapy. However, they are imperfect in predicting a pathological response in the era of modern systemic therapy with biological agents. The assessment of radiographical morphological changes is a better surrogate of the pathological response and survival especially in the patients treated with bevacizumab. Resectability of CLM is dependent on both anatomic and oncological factors. To decrease the surgical risk, a sufficient volume of liver remnant with adequate blood perfusion and biliary drainage is required according to the degree of histopathological injury of the underlying liver. Portal vein embolization is sometimes required to decrease the surgical risk in a patient with small future liver remnant volume. As a complete radiological response does not signify a complete pathological response, liver resection should include all the site of a tumour detected prior to systemic treatment.

Survival after liver resection in metastatic colorectal cancer: review and meta-analysis of prognostic factors

Background

Hepatic metastases develop in approximately 50% of colorectal cancer (CRC) cases. We performed a review and meta-analysis to evaluate survival after resection of CRC liver metastases (CLMs) and estimated the summary effect for seven prognostic factors.

Methods

Studies published between 1999 and 2010, indexed on Medline, that reported survival after resection of CLMs, were reviewed. Meta-relative risks for survival by prognostic factor were calculated, stratified by study size and annual clinic volume. Cumulative meta-analysis results by annual clinic volume were plotted.

Results

Five- and 10-year survival ranged from 16% to 74% (median 38%) and 9% to 69% (median 26%), respectively, based on 60 studies. The overall summary median survival time was 3.6 (range: 1.7–7.3) years. Meta-relative risks (95% confidence intervals) by prognostic factor were: node positive primary, 1.6 (1.5–1.7); carcinoembryonic antigen level, 1.9 (1.1–3.2); extrahepatic disease, 1.9 (1.5–2.4); poor tumor grade, 1.9 (1.3–2.7); positive margin, 2.0 (1.7–2.5); >1 liver metastases, 1.6 (1.4–1.8); and >3 cm tumor diameter, 1.5 (1.3–1.8). Cumulative meta-analyses by annual clinic volume suggested improved survival with increasing volume.

Conclusion

The overall median survival following CLM liver resection was 3.6 years. All seven investigated prognostic factors showed a modest but significant predictive relationship with survival, and certain prognostic factors may prove useful in determining optimal therapeutic options. Due to the increasing complexity of surgical interventions for CLM and the inclusion of patients with higher disease burdens, future studies should consider the potential for selection and referral bias on survival.

ESMO Consensus Guidelines for management of patients with colon and rectal cancer. a personalized approach to clinical decision making

Colorectal cancer (CRC) is the most common tumour type in both sexes combined in Western countries. Although screening programmes including the implementation of faecal occult blood test and colonoscopy might be able to reduce mortality by removing precursor lesions and by making diagnosis at an earlier stage, the burden of disease and mortality is still high. Improvement of diagnostic and treatment options increased staging accuracy, functional outcome for early stages as well as survival. Although high quality surgery is still the mainstay of curative treatment, the management of CRC must be a multi-modal approach performed by an experienced multi-disciplinary expert team. Optimal choice of the individual treatment modality according to disease localization and extent, tumour biology and patient factors is able to maintain quality of life, enables long-term survival and even cure in selected patients by a combination of chemotherapy and surgery. Treatment decisions must be based on the available evidence, which has been the basis for this consensus conference-based guideline delivering a clear proposal for diagnostic and treatment measures in each stage of rectal and colon cancer and the individual clinical situations. This ESMO guideline is recommended to be used as the basis for treatment and management decisions.

Progression while receiving preoperative chemotherapy should not be an absolute contraindication to liver resection for colorectal metastases

PURPOSE

Tumor progression while receiving neoadjuvant chemotherapy (PD) has been associated with poor outcome and is commonly considered a contraindication to liver resection (LR). This study aims to clarify in a large multicenter setting whether PD is always a contraindication to LR.

METHODS

Data from the LiverMetSurvey international registry were analyzed. Patients undergoing LR for colorectal metastases without extrahepatic disease after neoadjuvant chemotherapy between 1990 and 2009 were reviewed.

RESULTS

Among 2143 patients, PD occurred in 176 (8.2 %). Risk of progression was increased after 5-FU or irinotecan (22.7 % vs. 6.8 % after other regimens, p < 0.0001; 14.9 % vs. 7.2 %, p < 0.0001), while it was reduced after oxaliplatin (5.6 % vs. 12.0 %, p < 0.0001) and still diminished among patients receiving targeted therapies (2.6 %). PD was an independent prognostic factor of survival at multivariate analysis (35 % vs. 49 %, p = 0.0006). In the PD group, 3 independent prognostic factors were identified: carcinoembryonic antigen (CEA) ≥ 200 ng/mL (p = 0.003), >3 metastases (p = 0.028), and tumor diameter ≥ 5 0 mm (p = 0.002). A survival predictive model showed that patients without any risk factors had 5-year survival rates of 53.3 %; good survival results were still observed if metastases were >3 or ≥ 50 mm (29.9 and 19.1 %, respectively). On the contrary, survival was less than 10 % at 3 years in the presence of >1 prognostic factor or CEA of ≥ 200 ng/mL.

CONCLUSIONS

PD is a negative prognostic factor, but it is not an absolute contraindication to LR. Patients with PD could be scheduled for LR except for those with >3 metastases and ≥ 50 mm, or CEA ≥ 200 ng/mL in whom further chemotherapy is recommended.

Curative strategies for liver metastases from colorectal cancer: a review

Colorectal cancer is a very common malignancy and frequently manifests with liver metastases, often without other systemic disease. Margin-negative (R0) resection of limited metastatic disease, in conjunction with systemic antineoplastic agents, is the primary treatment strategy, leading to long survival times for appropriately selected patients. There is debate over whether the primary tumor and secondaries should be removed at the same time or in a staged manner. Chemotherapy is effective in converting some unresectable liver metastases into resectable disease, with a correspondingly better survival outcome. However, the ideal chemotherapy with or without biological agents and when it should be administered in the course of treatment are uncertain. The role of neoadjuvant chemotherapy in initially resectable liver metastases is controversial. Local delivery of chemotherapy, with and without surgery, can lead to longer disease-free survival times, but it is not routinely used with curative intent. This review focuses on methods to maximize the disease-free survival interval using chemotherapy, surgery, and local methods.

Multi-modality treatment of colorectal liver metastases

Liver metastases synchronously or metachronously occur in approximately 50% of colorectal cancer patients. Multimodality comprehensive treatment is the best therapeutic strategy for these patients. However, the optimal pattern of multimodality therapy is still controversial, and it raises several significant concerns. Liver resection is the most important treatment for colorectal liver metastases. The definition of resectability has shifted to focus on the completion of R0 resection and normal liver function maintenance. The role of neoadjuvant and adjuvant chemotherapy still needs to be clarified. The management of either progression or complete remission during neoadjuvant chemotherapy is challenging. The optimal sequencing of surgery and chemotherapy in synchronous colorectal liver metastases patients is still unclear. Conversional chemotherapy, portal vein embolization, two-stage resection, and tumor ablation are effective approaches to improve resectability for initially unresectable patients. Several technical issues and concerns related to these methods need to be further explored. For patients with definitely unresectable liver disease, the necessity of resecting the primary tumor is still debatable, and evaluating and predicting the efficacy of targeted therapy deserve further investigation. This review discusses different patterns and important concerns of multidisciplinary treatment of colorectal liver metastases.

Surgery Combined with Oncological Treatments in Liver Metastases from Colorectal Cancer

The patients with colorectal liver metastases used to have a rather disappointing prognosis in the past. At present there is moderate possibility for cure with liver resection. In addition more patients are accessible for liver resection and potential cure when modern chemotherapy combined with biological agents is used. At the time of diagnosis liver metastases of 10–20% of patients are resectable. Potentially unresectable metastases can be converted to resectable in 10–15% of patients with advances in surgery together with improved oncological therapy. Resection rate increases linearly with the response rate to chemotherapy. In this century the 5-year survival rates after resection have improved remarkably being around 50% in many reports. Multidisciplinary management of metastatic colorectal cancer has increased the number of patients with potentially curative treatment and has improved patient survival.