Cell proliferation-related markers in colorectal liver metastases: correlation with patient prognosis

Surgical Strategies in Colorectal Cancer Metastatic to the Liver

Surgical resection remains a milestone in the treatment of colorectal metastases to the liver. There is a distinct subset of patients who benefit from surgical resection in terms of longer survival or definitive cure. The main effort of the surgical oncological regards the safety of the procedure and the adequacy of the recommendation. Many studies, some of them including multivariate analysis, have shown the presence of prognostic determinants of long-term survival and prognostic indexes of the outcome after hepatectomy. It is now accepted that liver resection should be done when the complete excision of all demonstrable tumor with clear resection margins is feasible. Major contra-indication is represented by the presence of extra-hepatic intra-abdominal disease or of unresectable lung metastatic deposits. There is a wide literature indicating that in very selected patients liver reresection and multiorgan synchronous or metachronous resections are beneficial. The role of neoadjuvant chemotherapy and especially postoperative adjuvant local (intra-hepatic) and systemic chemotherapy is promising and supported by recent multicenter randomised clinical trials.

Management of patients with colorectal liver metastasis in eleven questions and answers

INTRODUCTION

Colorectal liver metastasis (CRLM) is the most frequent indication for liver resection in many centers. Recent improvements in oncology, surgery, interventional radiology, pathology and anesthesiology allow curative treatment in a larger proportion of patients with CRLM. Areas covered: We illustrate the various aspects of the management of CRLM through 11 questions that summarize the topic, from the current obtained survival to future perspectives such as transplantation. The limits of a curative treatment are also presented from different angles, such as the benefits of pathology, the surgical options for extreme resections, the available chemotherapies and their efficacy, or the non-surgical ablative treatments. Expert commentary: Given the increasing therapeutic possibilities, we strengthen the importance to analyze the situation of each patient with CRLM in a dedicated multidisciplinary team, in order to offer the best individualized treatment combination.

Management of colorectal cancer patients after resection of liver metastases: can we offer a tailored treatment?

Surgical resection remains the only option of cure for patients with colorectal liver metastases, and no patient should be precluded from surgery. There is much controversy not only regarding the most appropriate therapeutic approach in the neoadjuvant setting but also after surgery is performed. Many patients will experience early relapses but others will be long survivors. We need to establish reliable prognostic and predictive factors to offer a tailored treatment. Several prognostic factors after metastasectomy have been identified: high C-reactive protein levels, a high neutrophil-lymphocyte ratio, elevated neutrophil count and low serum albumin are related to a worst outcome. Elevated CEA and Ki 67 levels, intrahepatic and perihepatic lymph node invasion are also some of the markers related to a worst outcome. In contrast, the administration of preoperative chemotherapy has been associated with a better prognosis after hepatectomy. The administration of adjuvant chemotherapy should be done taking in consideration these factors. Regarding predictive factors, determination of ERCC1, TS, TP and DPD and UGT1 polymorphisms assessment could be considered prior to chemotherapy administration. This would avoid treatment related toxicities and increase this population quality of life.

Surgical therapy for colorectal metastases to the liver

Colorectal cancer is the fourth most common type of cancer in the West and the second leading cause of cancer-related deaths in the United States. Approximately 35 to 55% of patients with colorectal cancer develop hepatic metastases during the course of their disease. Surgical resection of colorectal liver metastases represents the only chance at potential cure, and long-term survival can be achieved in 35 to 58% of patients after resection. The goal of hepatic resection should be to resect all metastases with negative histologic margins while preserving sufficient functional hepatic parenchyma. In patients with extensive metastatic disease who would otherwise be unresectable, ablative approaches can be used instead of or combined with hepatic resection. The use of portal vein embolization and preoperative chemotherapy may also expand the population of patients who are candidates for surgical treatment. Despite these advances, many patients still experience a recurrence after hepatic resection. More active systemic chemotherapy agents are now available and are being increasingly employed as adjuvant therapy either before or after surgery. Modern treatment of colorectal liver metastasis requires a multidisciplinary approach in an effort to increase the number of patients who may benefit from surgical treatment of colorectal cancer liver metastasis.

Neoadjuvant chemotherapy for patients with liver metastases from colorectal cancer

Colorectal cancer is the second most common type of cancer in industrialized countries. Despite improved resection procedures and optimized adjuvant chemotherapy, local or distant recurrences occur in 22-25% of patients with stage II/III colon cancer. Approximately 30% of patients have advanced disease at presentation. The liver is the most common site of colorectal metastases and, interestingly, 20-30% of patients with colorectal cancer have liver-only metastases. The combined modality of chemotherapy and surgery increases overall survival and the chance of cure for metastatic patients, even if there is no agreement in terms of the best schedule and how long the treatment must last. In this paper, we review the role and the rationale of neoadjuvant chemotherapy within a multimodal approach, and discuss remaining questions and future directions.

Shifting from clinical to biologic indicators of prognosis after resection of hepatic colorectal metastases

Following resection of hepatic colorectal metastases, there are few criteria for predicting which patients have more aggressive disease and are, therefore, more likely to experience recurrence and reduced survival. Traditionally, primary tumor stage, preoperative carcinoembryonic antigen level, time from primary tumor treatment to diagnosis of hepatic metastases (disease-free interval), hepatic tumor size, number of hepatic metastases, and presence of extrahepatic disease have been reported to be predictors of survival after resection. However, the data regarding the prognostic importance of these clinicopathologic factors are inconsistent and conflicting. Therefore, conventional clinicopathologic factors may be inadequate for the purposes of prognostication. More recently, there has been increased interest in identifying biologic indicators that may help better define patients at risk for recurrence after hepatic resection for colorectal metastases. Recent studies have shown that proliferation markers such as p53 expression, tritiated thymidine uptake, thymidylate synthase, Ki-67, and human telomerase reverse transcriptase may be better predictors of outcome after resection of hepatic colorectal metastases. Moreover, tumor response to preoperative chemotherapy may also prove to be a useful predictor of outcome following liver resection for colorectal metastases.

Molecular prognostic markers in resectable colorectal liver metastases: A systematic review

BACKGROUND

Determination of prognosis in patients with resectable colorectal liver metastases (CLM) is desirable in order to improve case selection for surgery and tailor adjuvant treatment according to individual recurrence risk. Conventional clinicopathological factors lack the sensitivity to accurately achieve this goal. Consideration of tumour biology and the identification of molecular prognostic markers may allow more accurate risk stratification.

METHOD

This systematic review examines evidence from published manuscripts looking at molecular markers in resectable colorectal liver metastases and their correlation with disease recurrence and survival following hepatectomy.

RESULTS

Studies have yielded promising results in the search for prognostic molecular markers of CLM. Molecular biomarkers from varied aspects of tumour biology have been examined and a number of these, including proliferation indices, telomerase, thymidylate synthase, microvessel density and thrombospondin-1 appear to have prognostic utility in this context. Validation of other markers, notably p53, has been limited by a failure of methodologies to account for their biological complexity.

CONCLUSIONS

A biomarker-based approach may yield significant benefits through informed treatment of resectable metastatic colorectal malignancy. Standardised retrospective analyses are necessary to confirm preliminary findings and identify existing and novel markers for inclusion into prospective studies. Assessment and verification of multiple molecular markers in this manner may allow molecular profiling of metastases and tailoring of therapy according to the biological aggressiveness of individual tumours. The advent of genomic- and proteomic-based technologies will allow the simultaneous analysis of multiple molecular markers and the derivation of disease profiles associated with disease recurrence and poor survival.

Association of k-ras, b-raf, and p53 status with the treatment effect of bevacizumab

BACKGROUND

A recent phase III trial showed that the addition of bevacizumab, a monoclonal antibody to vascular endothelial growth factor-A, to first-line irinotecan, 5-fluorouracil, and leucovorin (IFL) prolonged median survival in patients with metastatic colorectal cancer. We carried out a retrospective analysis of patients in the trial to evaluate whether mutation status of k-ras, b-raf, or p53 or P53 expression could predict which patients were more likely to respond to bevacizumab.

METHODS

Microdissected tumors from 295 patients (274 primary tumors, 21 metastases) were subject to DNA sequence analysis to identify mutations in k-ras, b-raf, and p53. Nuclear P53 expression was determined by immunohistochemistry. Hazard ratios and 95% confidence intervals (CI) for overall survival were estimated using Cox regression analysis.

RESULTS

In all biomarker subgroups, estimated hazard ratios for risk of death were less than 1 for bevacizumab-treated patients as compared with those for placebo-treated patients. Mutations in k-ras and/or b-raf were observed in 88 of 213 patients (41%). Hazard ratios for death among patients with tumors with wild-type k-ras/b-raf status, as compared with those of patients with mutations in one or both genes, were 0.51 (95% CI = 0.28 to 0.95) among those treated with IFL plus bevacizumab and 0.66 (95% CI = 0.37 to 1.18) among those treated with IFL plus placebo. Mutations in p53 were found in 139 of 205 patients (68%), and P53 was overexpressed in 191 of 266 patients (72%); neither p53 mutation nor P53 overexpression was statistically significantly associated with survival.

CONCLUSIONS

We did not find a statistically significant relationship between mutations of k-ras, b-raf, or p53 and the increase in median survival associated with the addition of bevacizumab to IFL in metastatic colorectal cancer.

Catalytic Subunit of Human Telomerase Reverse Transcriptase Is an Independent Predictor of Survival in Patients Undergoing Curative Resection of Hepatic Colorectal Metastases: A Multicenter Analysis

Purpose

To determine the role of the catalytic subunit of human telomerase reverse transcriptase (hTERT) in predicting survival after resection of hepatic colorectal metastases (CRM).

Patients and Methods

Two hundred one patients who underwent curative resection of hepatic CRM between 1990 and 2000 were identified from a multicenter database. The CRM were analyzed for hTERT nucleolar expression by standard immunohistochemical techniques. hTERT expression and known clinicopathologic factors of survival were examined.

Results

With a median follow-up of 80 months, 152 patients (75.6%) had died; the 5-year overall survival was 30.7%. On univariate analysis, number of metastases greater than two (P = .0005), extrahepatic disease (P = .0054), disease-free interval less than 12 months (P = .006), carcinoembryonic antigen level greater than 200 ng/mL (P = .0071), and positive hTERT nucleolar staining (P < .0001) were associated with decreased survival. On multivariate analysis, three factors independently predicted survival: number of metastases (relative risk [RR] = 1.74; P = .0011); disease-free interval (RR = 1.70; P = .0035); and positive hTERT nucleolar staining (RR = 2.03; P < .0001). Patients with none or one of these factors had a 5-year survival rate of 48%, whereas those with two or three of these factors had a 5-year survival of 15% (P < .0001).

Conclusion

hTERT nucleolar expression is associated with worse survival after resection of hepatic CRM. hTERT expression in conjunction with number of hepatic metastases and disease-free interval may permit more accurate prediction of survival after resection of hepatic CRM.

Microsatellite Instability as a Prognostic Factor in Resected Colorectal Cancer Liver Metastases

BACKGROUND

Two distinct genetic mutational pathways characterized by either chromosomal instability or high-frequency microsatellite instability (MSI-H) are currently recognized in the pathogenesis of colorectal cancer (CRC). Recently, it has been shown that patients with primary CRC that displays MSI-H have a significant, stage-independent, multivariate survival advantage. Untreated CRC hepatic metastases are incurable and are associated with a median survival of 4 to 12 months. Conversely, surgical resection in selected patients results in a 20% to 50% cure rate. The aim of this study was to investigate the prognostic importance of MSI-H in patients undergoing resection of hepatic CRC metastases.

METHODS

DNA was extracted from paraffin-embedded, resected metastatic CRC liver lesions and corresponding normal liver parenchyma from 190 patients. MSI-H status was determined by polymerase chain reaction-based evaluation of the noncoding mononucleotide repeats BAT-25 and BAT-26.

RESULTS

MSI was detected in tumors from 5 (2.7%) of the 190 CRC patients. All MSI-H tumors were in patients with node-positive CRC primary tumors. The median survival after hepatic resection of MSI-H and non-MSI-H tumors was 67 and 61 months, respectively (P = .9).

CONCLUSIONS

These data suggest that MSI-H is not a common feature in resected CRC liver metastases and do not suggest a role for MSI in stratifying good versus poor prognosis in these patients.

p53 and HLA class-I expression are not down-regulated in colorectal cancer liver metastases

p53 overexpression occurs in more than 50% of colorectal carcinomas, which makes it an interesting target for immunotherapy. HLA class I expression on tumor cells is required for the presentation of p53 peptides and an effective T-cell mediated-immune response to ensue. To analyze to which extent p53 and HLA-I expression in a primary tumor reflects expression in liver metastases, we investigated p53, HLA-A and HLA-B/C expression in 82 colorectal carcinomas and 143 associated liver metastases of 82 patients. We used the monoclonal antibodies DO-7 (p53), HCA2 (HLA-A) and HC-10 (HLA-B/C) on formalin-fixed, paraffin embedded tissue. The percentage of expressing cells was estimated. P53 was overexpressed in 73% of the colorectal carcinomas and 66% of liver metastases. HLA-A was expressed in 98% and 96% and HLA-B/C in 100% and 94% of colorectal cancers and liver metastases respectively. There were no significant differences between the primary tumors and the liver metastases for each marker. The concordance was also very high in those cases in which more than one metastasis was available. Discordant cases consisted of tumors in which expression of p53 or HLA-A was lost in the liver metastases, whereas it was present in only a few tumor cells in the primary tumor. The combined analysis of p53 and HLA-I expression in liver metastases demonstrated that both molecules were expressed in 63% of the cases. P53 and HLA-I were expressed in the majority of primary tumors and their associated liver metastases. This allows to select patients for p53-immunotherapy on the basis of p53 and HLA-I expression in the primary tumor.

Human telomerase reverse transcriptase (hTERT) and Ki-67 are better predictors of survival than established clinical indicators in patients undergoing curative hepatic resection for colorectal metastases

BACKGROUND

We evaluated hTERT and Ki-67 expression in patients who underwent curative resection of hepatic colorectal metastases to determine if these markers of cell proliferation correlated better with survival than an established scoring system that is based on clinical predictors.

METHODS

Patients operated on between 1993 and 1997 whose survival time was known were analyzed. For each patient, the clinical prognostic score was derived on the basis of primary node status, disease-free interval, number of hepatic tumors, largest tumor, and carcinoembryonic antigen level, and tumor specimens were analyzed for Ki-67 and hTERT with use of standard immunohistochemical techniques. The immunohistochemical analysis was blinded to all patient characteristics.

RESULTS

The study included 66 patients. Twenty-six survived less than 2 years after surgery, 19 survived 2-5 years, and 21 survived more than 5 years. Ki-67 positivity and hTERT positivity (labeling indexes greater than or equal to 50%) were observed in 24 patients and 23 patients, respectively. The clinical score did not predict survival, although there was a weak trend toward a lower score in patients with better survival. Both Ki-67 (P =.04) and hTERT (P =.0001) correlated better with survival than did the clinical score.

CONCLUSIONS

In patients undergoing curative resection of hepatic colorectal metastases, hTERT and Ki-67 are better predictors of survival than is a score based on clinical features.

A critical review of the major indicators of prognosis after resection of hepatic metastases from colorectal carcinoma

Hepatic resections for metastatic colorectal cancer have dramatically increased, and there is clear evidence of the effectiveness of this type of surgery. Controversy, however, persists regarding appropriate patient selection, extent and timing of liver resection, and adjuvant or alternative therapeutic options. This article reviews the authors' experience with more than 600 hepatic resections and the relevant literature is discussed. The results underscore the importance of macroscopically and histologically complete tumor clearance, a so-called "R0 resection."

p53, DCC and thymidylate synthase as predictors of survival after resection of hepatic metastases from colorectal cancer

BACKGROUND

Hepatic metastasis from colorectal cancer is a common problem. Hepatic resection offers the only chance of cure. Prognosis of patients following hepatic resection is currently based on clinicopathological factors (of both the primary cancer and the hepatic metastasis), which do not accurately predict the subsequent behaviour of the tumour. The aim of this study was to evaluate three molecular genetic markers - p53, DCC (deleted in colonic cancer) and thymidylate synthase - in both the primary colorectal tumour and the resected hepatic metastases, and to determine their correlation, if any, with survival in patients with resected hepatic metastases from colorectal cancer.

METHODS

Sixty-three patients with hepatic metastases and 40 corresponding colorectal primary tumours were studied using immunohistochemical staining for p53, DCC and thymidylate synthase, as well as p53 gene mutations using polymerase chain reaction-single-stranded conformational polymorphism (PCR-SSCP) analysis. The results were correlated with survival.

RESULTS

There was no correlation between p53, DCC or thymidylate synthase immunohistochemical staining, or between p53 PCR-SSCP analysis, and survival for either hepatic metastases or the colorectal primary tumour.

CONCLUSION

Prediction of prognosis in patients having resection of hepatic metastases from colorectal cancer continues to be problematic. Other genetic markers or combination of markers need to be evaluated.

2000 update of recommendations for the use of tumor markers in breast and colorectal cancer: clinical practice guidelines of the American Society of Clinical Oncology

OBJECTIVE

To update the 1997 clinical practice guidelines for the use of tumor marker tests in the prevention, screening, treatment, and surveillance of breast and colorectal cancers. These guidelines are intended for use in the care of patients outside of clinical trials.

OPTIONS

Six tumor markers for colorectal cancer and eight for breast cancer were considered. They could be recommended or not for routine use or for special circumstances. In addition to carcinoembryonic antigen (CEA) and CA 15-3, CA 27.29 was also considered among the serum tumor markers for breast cancer.

OUTCOMES

In general, the significant health outcomes identified for use in making clinical practice guidelines (overall survival, disease-free survival, quality of life, lesser toxicity, and cost-effectiveness) were used.

EVIDENCE

A computerized literature search from 1994 to March 1999 was performed.

VALUES

The same values for use, utility, and levels of evidence were used by the committee.

BENEFITS, HARMS, AND COSTS

The same benefit, harms, and costs were used.

RECOMMENDATION

Changes were recommended (see Appendix).

VALIDATION

The updated recommendations were validated by external review by the American Society of Clinical Oncology's (ASCO's) Health Services Research Committee and by ASCO's Board of Directors.

SPONSOR

American Society of Clinical Oncology.

Expression of apoptosis-related markers and clinical outcome in patients with advanced colorectal cancer

The clinical relevance of bax and bcl-2 protein expression has been investigated in 84 patients with recurrent or metastatic colorectal cancer submitted to a chemotherapy regimen including methotrexate and fluorouracil/leucovorin. Cytoplasmic immunostaining of bax and bcl-2 was present in 65.5% and 38%, respectively, of the tumours. No association was found between bax and bcl-2 or between p53 and bax or bcl-2 protein expression. Moreover, the biomarkers were unrelated to patient and tumour characteristics known to affect the clinical outcome of colorectal cancer patients. In general, the apoptosis-related markers did not appear indicative of short- and long-term clinical response nor of prognosis. Bcl-2-negative lesions were more frequent among patients who reached an objective clinical response, which is in agreement with previously reported data regarding other tumour types. When the interrelationship between p53 and bax expression was examined, a better response rate (40%) was found for patients whose tumours did not express p53 and bax, and a better prognosis (2-year probability of overall survival 75%) for patients with p53-positive and bax-negative tumours. In the present series of patients with advanced colorectal cancer submitted to systemic chemotherapy we did not find a clear association between expression of apoptosis-related markers and clinical outcome, even in the subset of patients in which the apoptotic index as determined by the TUNEL approach was investigated.

Relevance of Ki-67 antigen expression and K-ras mutation in colorectal liver metastases

AIMS

The liver is a frequent site of metastases from colorectal cancer. While these lesions are potentially amenable to surgical resection, they are usually very aggressive, and recurrence is frequent. Mutations of the proto-oncogene K- ras are thought to impart a strong growth signal to tumour cells and are closely associated with the development of malignancies of the colon and rectum. Hepatic metastases from colorectal cancer have notably elevated proliferative rates. The present study was performed to investigate the relationship between proliferation or K- ras mutation and prognosis following curative resection of colorectal liver metastases.

METHODS

Colorectal liver metastases from 41 patients undergoing curative hepatic resection were examined for proliferation status and presence of K- ras mutations. The proliferative activity was assessed by Ki-67 immunohistochemistry. DNA from the same tissue samples was screened for point mutations in codon 12 of the K- ras gene using a novel microplate-based allelic-specific hybridization assay. Ki-67 scores and K- ras status were then related with patient survival as determined through retrospective analysis.

RESULTS

Median survival was 40 months. Patients with high Ki-67 scores (> or = 50%) had significantly shorter median survival compared with those with low scores (30 vs 44 months, log-rank P=0.02). A high Ki-67 score was an independent negative prognostic factor by multivariate regression analysis (relative risk=3.04, P=0.036). K- ras point mutations were detected in 6/41 patients (15%), but mutational status did not correlate with Ki-67 score or survival.

CONCLUSIONS

These findings suggest that the tumour proliferative index is a useful predictor of aggressive tumour behaviour and an indicator of patient survival. The presence of K- ras mutations does not appear to correlate with tumour proliferation status or patient survival.

Extension of the frontiers of surgical indications in the treatment of liver metastases from colorectal cancer: long-term results

OBJECTIVE

To evaluate retrospectively the long-term results of an approach consisting of performing surgery in every patient in whom radical removal of all metastatic disease was technically feasible.

SUMMARY BACKGROUND DATA

The indications for surgical resection for liver metastases from colorectal cancer remain controversial. Several clinical risk factors have been reported to influence survival.

METHODS

Between March 1980 and December 1997, 235 patients underwent hepatic resection for metastatic colorectal cancer. Survival rates and disease-free survival as a function of clinical and pathologic determinants were examined retrospectively with univariate and multivariate analyses.

RESULTS

The overall 3-, 5-, 10-, and 15-year survival rates were 51%, 38%, 26%, and 24%, respectively. The stage of the primary tumor, lymph node metastasis, and multiple nodules were significantly associated with a poor prognosis in both univariate and multivariate analyses. Disease-free survival was significantly influenced by lymph node metastasis, a short interval between treatment of the primary and metastatic tumors, and a high preoperative level of carcinoembryonic antigen. The 10-year survival rate of patients with four or more nodules (29%) was better than that of patients with two or three nodules (16%), and similar to that of patients with a solitary lesion (32%).

CONCLUSIONS

Surgical resection is useful for treating liver metastases from colorectal cancer. Although multiple metastases significantly impaired the prognosis, the life expectancy of patients with four or more nodules mandates removal.

Biological considerations with pelvic neoplasms

The strategy of therapy for any neoplasm is determined to a significant degree by the biological characteristics of the neoplasm. The ones benefited most by surgical ablation are the cancers that grow locally but never metastasize. The second group is composed of neoplasms with exceedingly slow growth rates permitting long periods of symptom-free survival before recidivation. Many such cancers occur in pelvic structures requiring understanding of the nature of the cancers and then techniques necessary for their resection. The review provides an introduction to some of the relevant biological considerations.

Resection of liver metastases from colorectal cancer: the real impact of the surgical margin

AIMS

The benefit of liver resection for metastatic colorectal cancer is now established. Nevertheless if the surgical margin on pre-operative imaging is considered to be less than 10 mm, this is considered an absolute contraindication to surgery by some, and a relative contraindication by others, so its real impact on prognosis is not clear.

METHODS

From 1984 to 1996, 269 patients underwent hepatectomy for liver metastases and were prospectively studied. The only two objectives of this surgery were to be curative (or achieve complete R0 resection), and to avoid mortality. Of the 269, 187 patients had surgical margins inferior to 10 mm. Sixty per cent had multiple liver metastases, and 37% had extrahepatic metastatic sites. Their clinical and pathological factors were specifically studied.

RESULTS

The crude 5-year survival of these 187 patients (including the 2% post-operative mortality) was 24.7%, and the disease-free survival was 18.8%. The surgical margin was 0 mm in 60 cases and was histologically invaded in 20 cases. The most important prognostic factor was whether the resection was considered palliative (R1-R2 resection according to UICC criteria) (P < 0.0001). When the cases with invaded margins were excluded, there was not prognostic difference between the 107 patients with a margin of 0-4 mm and the 143 patients with a margin greater than 4 mm. However, a surgical margin greater than 9 mm appears to be a second prognostic factor (P = 0.001), when these 187 patients are compared to others. The reasons behind this are that there is a close relationship between narrow margins and extensive disease (high number of metastases, bilateral localization and extended hepatectomy), and also an increased possibility of microscopic satellite lesions within 10 mm around the metastases.

CONCLUSION

The real prognostic impact of the surgical margin must not be overestimated. Hepatectomy for metastases can provide long-term survival in patients with supposed poor prognostic factors. Resection is justified so long as it is complete and with minimal risk. An experienced, specialized centre can be a prognostic determinant.