CEA reduction after cryotherapy for liver metastases from colon cancer predicts survival

Presence of CD44v9-Expressing Cancer Stem Cells in Circulating Tumor Cells and Effects of Carcinoembryonic Antigen Levels on the Prognosis of Colorectal Cancer

Circulating tumor cells (CTCs) are cancer cells released from the primary tumor into the bloodstream, and contain cancer stem cells that influence tumor survival, recurrence, and metastasis. Here, we investigated CD44v9 expression in CTCs and impact of preoperative carcinoembryonic antigen (CEA) levels on colorectal cancer (CRC) prognosis. We analyzed the expression of CD44v9 mRNA in CTCs using reverse transcription-polymerase chain reaction and preoperative CEA levels in blood samples obtained from 300 patients with CRC. Subsequently, we evaluated the association of CD44v9 expression and CEA levels with clinicopathological factors. CD44v9 mRNA was expressed in 31.3% of the patients, and was significantly associated with liver metastasis. Patients with positive CD44v9 expression had a lower 5-year survival rate (62.3%) than those with negative CD44v9 expression (82.8%, p < 0.001). Cox regression analysis identified CD44v9 expression and high CEA levels (≥5 ng/mL) as poor prognostic factors, while negative CD44v9 expression and low CEA levels (<5 ng/mL) were associated with favorable prognosis (hazard ratio = 0.285, p = 0.006). These results suggest that a combination of CD44v9 mRNA expression in CTCs and serum CEA levels could serve as a valuable prognostic marker for CRC, potentially enhancing the accuracy of prognosis predictions.

Clinical significance of changes in systemic inflammatory markers and carcinoembryonic antigen levels in predicting metastatic colorectal cancer prognosis and chemotherapy response

AIM

Metastatic colorectal cancer (mCRC) is associated with poor prognosis, and biomarkers are required for predicting survival and chemotherapy response. This study aimed to evaluate the significance of changes in systemic inflammatory markers and carcinoembryonic antigen (CEA) levels in predicting mCRC prognosis and chemotherapy response.

METHODS

In this retrospective study, 503 patients who received first-line palliative chemotherapy for mCRC between 2008 and 2014 at a tertiary hospital in Korea were evaluated. Changes in neutrophil-to-lymphocyte ratio (NLR) and modified Glasgow prognostic score (mGPS) were divided into low-to-low, high-to-low, low-to-high and high-to-high groups. The CEA response was defined as CEA-complete response (CEA normalization), CEA-partial response (≥50% decrease in CEA levels), CEA-progressive disease (≥50% increase in CEA levels) and CEA-stable disease. Overall survival (OS) and progression-free survival (PFS) were evaluated according to NLR, mGPS and CEA levels.

RESULTS

High prechemotherapy NLR, mGPS and CEA levels independently predicted poor survival and chemotherapy response. Continuously high NLR or change to high NLR was also associated with poor OS and PFS; however, continuously low NLR or reduced NLR showed good prognosis. CEA response was also an independent prognostic marker for OS and PFS. High NLR and mGPS were correlated with elevated CEA levels.

CONCLUSION

Inflammatory marker levels were significantly associated with CEA levels. The prechemotherapy levels of systemic inflammatory markers and CEA were associated with OS or PFS. The change patterns in NLR and CEA levels can be utilized as prognostic and predictive markers for chemotherapy response.

Clinical Significance of Discordance between Carcinoembryonic Antigen Levels and RECIST in Metastatic Colorectal Cancer

Purpose

The purpose of this study was to investigate the prognostic implications of carcinoembryonic antigen (CEA) levels that are inconsistent with Response Evaluation Criteria in Solid Tumor (RECIST) responses in metastatic colorectal cancer patients.

Materials and Methods

We retrospectively evaluated 360 patients with at least one measurable lesion who received first-line palliative chemotherapy. CEA-response was defined as CEA-complete response (CR; CEA normalization), CEA-partial response (PR; ≥ 50% decrease in CEA levels), CEA-progressive disease (PD; ≥ 50% increase in CEA levels), and CEA-stable disease (SD; non-CR/PR/PD). Overall survival (OS) and progression-free survival (PFS) were evaluated according to CEA-response.

Results

In RECIST-PR patients, poorer CEA-response was associated with disease progression at the subsequent evaluation. In RECIST-SD patients, CEA-CR and -PR were associated with lower disease progression rates than CEA-PD at the subsequent evaluation. Correlations between survival outcome and CEA-response in same-category RECIST patients were assessed. In RECIST-PR patients, discordant CEA-response (CEA-PD/SD) was associated with poorer survival than CEA-CR/PR (median OS and PFS, 44.0 and 15.4 [CEA-CR], 28.9 and 12.5 [CEA-PR], 21.0 and 9.8 [CEA-SD], and 13.0 and 7.0 [CEA-PD] months, respectively; all p < 0.001). In RECIST-SD patients, favorable CEA-response produced better survival (median OS and PFS, 26.8 and 21.0 [CEA-CR], 21.0 and 11.0 [CEA-PR], 16.1 and 8.2 [CEA-SD], and 12.2 and 6.0 [CEA-PD] months, respectively; all p < 0.001). RECIST-PD patients with CEA-CR showed longer OS than those with CEA-PD. Multivariate analysis demonstrated that discordant CEA-response is a powerful prognostic factor for RECIST-PR and RECIST-SD patients.

Conclusion

Among patients of the same RECIST-response categories, CEA-response patterns are significantly prognostic and strongly predictive of subsequent evaluation outcomes.

Concordance of Carcinoembryonic Antigen Ratio and Response Evaluation Criteria in Solid Tumors as Prognostic Surrogate Indicators of Metastatic Colorectal Cancer Patients Treated with Chemotherapy

BACKGROUND

Carcinoembryonic antigen (CEA) is widely used as a tumor marker in colorectal cancer (CRC). This study aimed to evaluate the role of the degree of change in CEA levels during the treatment period and found that the degree of change highly correlated with disease survival and Response Evaluation Criteria in Solid Tumors (RECIST) criteria in evaluating therapy response.

METHODS

A total of 447 metastatic CRC patients treated with surgery of the primary tumor followed by systemic therapy at a single center from the year 2000 through 2011 were reviewed. The degree of change in CEA levels was expressed as the CEA ratio (post-CEA/pre-CEA) and classified into four groups during the treatment period for further evaluation. The imaging change of the same population was also compared with the CEA ratio during the treatment period.

RESULTS

The CEA ratio was significantly correlated with different chemotherapy regimens (p < 0.001), pre-treatment CEA level (p < 0.001), lymphovascular invasion (p = 0.006), and tumor differentiation (p = 0.018). CEA ratio and imaging change according to RECIST criteria were both correlated with overall survival (p < 0.001). These two methods for evaluating treatment response were highly correlated (p < 0.001).

CONCLUSIONS

CEA ratio was found to be a reliable prognostic factor in stage IV CRC, and was highly correlated with the imaging survey according to RECIST criteria. Further prospective studies are essential to validate these findings.

Carcinoembryonic Antigen in the Staging and Follow-up of Patients with Colorectal Cancer

CEA is a complex glycoprotein produced by 90% of colorectal cancers and contributes to the malignant characteristics of a tumor. It can be measured in serum quantitatively, and its level in plasma can be useful as a marker of disease. Because of its lack of sensitivity in the early stages of colorectal cancer, CEA measurement is an unsuitable modality for population screening. An elevated preoperative CEA is a poor prognostic sign and correlates with reduced overall survival after surgical resection of colorectal carcinoma. A failure of the CEA to return to normal levels after surgical resection is indicative of inadequate resection of occult systemic disease. Frequent monitoring of CEA postoperatively may allow identification of patients with metastatic disease for whom surgical resection or other localized therapy might be potentially beneficial. To identify this group, serial CEA measurement appears to be more effective than clinical evaluation or any other diagnostic modality, although its sensitivity for detecting recurrent disease is not as high for locoregional or pulmonary metastases as it is for liver metastases. Several studies have shown that a small percentage of patients followed postoperatively with CEA monitoring and who undergo CEA-directed salvage surgery for metastatic disease will be alive and disease-free 5 years after surgery. Furthermore, CEA levels after salvage surgery do appear to predict survival in patients undergoing resection of liver or pulmonary metastases. However, several authors argue that CEA surveillance is not cost-effective in terms of lives saved. In support of this argument, there is no clear difference in survival after resection of metastatic disease with curative intent between patients in whom the second-look surgery was performed on the basis of elevated CEA levels and those with other laboratory or imaging abnormalities. There is also no clear consensus on the frequency or duration of CEA monitoring, although the ASCO guidelines currently recommend every 2-3 months for at least 2 years after diagnosis. In the follow-up of patients undergoing palliative therapy, the CEA level correlates well with response, and CEA is indicative of not only response but may also identify patients with stable disease for whom there is also a demonstrated benefit in survival and symptom relief with combination chemotherapy. More recently, scintigraphic imaging after administration of radiolabeled antibodies afforded an important radionuclide technique that adds clinically significant information in assessing the extent and location of disease in patients with colorectal cancer above and beyond or complementary to conventional imaging modalities. Immunotherapy based on CEA is a rapidly advancing area of clinical research demonstrating antibody and T-cell responses.

Applying Fong's CRS Liver Score in Patients with Colorectal Liver Metastases Treated by Cryotherapy

BACKGROUND

A significant proportion of patients with liver metastases from colorectal cancer have unresectable disease and we have used cytoablative treatment such as cryotherapy in some of these patients. We retrospectively reviewed patients who underwent hepatic cryotherapy for colorectal metastases and studied the effect of the clinical risk score (CRS) reported by Fong et al, which can predict survival following liver resection.

METHODS

A retrospective study was performed on patients who underwent hepatic cryotherapy between 1990 and 2000 in St George Hospital. There were 61 patients in this study and they were stratified into prognostic groups based on five preoperative CRS parameters: primary node positive, disease-free interval from primary to metastases < 12 months, number of hepatic tumours > 1, largest hepatic tumour > 5 cm and carcinoembryonic antigen level > 200 ng/mL. The median follow-up was 25 months.

RESULTS

The median survival was 26 months and the 3-year survival rate was 37%. Median survivals for patients with CRS scores 1 (13%), 2 (25%), 3 (53%), 4 (6%) and 5 (4%) were 37, 25, 30, 21 and 15 months, respectively (R2 = 0.81).

CONCLUSION

The CRS score can be used to predict outcome of hepatic cryotherapy, but the difference in survival between CRS 2, 3 and 4 is modest.

Recurrence after Complete Cryoablation of Colorectal Liver Metastases: Analysis of Prognostic Features

This study critically evaluated the prognostic determinants for disease-free survival (DFS) after cryoablation for colorectal liver metastases. An observational cohort study of prospectively collected data on 135 patients who underwent cryoablation with or without resection for colorectal liver metastases was performed. Univariate and multivariate analyses were used to determine the prognostic factors for overall DFS, cryosite DFS, remaining liver DFS, and extrahepatic DFS. Overall, 115 patients (85%) developed recurrence at the cryosite (44%), and the remaining patients developed recurrence at the liver (62%) and extrahepatic site (71%). In univariate analysis, pre-operative and postoperative carcinoembryonic antigen (CEA) were significant for overall DFS. Distribution of metastases, operation type, total number of metastases, number of cryotreated metastases, largest size of cryotreated metastasis, and postoperative CEA were significant for cryosite DFS. The number of cryotreated metastases and postoperative CEA were significant for remaining liver DFS. The largest size of cryotreated metastasis, and preoperative and postoperative CEA were significant for extrahepatic DFS. In multivariate analysis, resection plus cryoablation, ≤7 liver metastases and ≤3 cm cryotreated metastasis were independently associated with an improved cryosite DFS. Preoperative CEA of ≤5 ng/mL was independently associated with an improved overall and extrahepatic DFS. The role of CEA in colorectal metastasis is important. Resection plus cryoablation rather than cryoablation alone should be used for larger lesions.

Longterm Results and Prognostic Indicators after Cryotherapy and Hepatic Arterial Chemotherapy With or Without Resection for Colorectal Liver Metastases in 224 Patients: Longterm Survival Can Be Achieved in Patients With Multiple Bilateral Liver Metastases

BACKGROUND

Only a minority of patients are suitable for liver resection for colorectal liver metastases. Cryotherapy was the first widely used ablative technique, achieving a median survival of more than 2 years. Patient selection is important, but the prognostic criteria have been controversial. The combined treatment modality of cryotherapy, resection, and hepatic arterial chemotherapy has been used in treating unresectable liver disease. Many centers would not surgically treat patients with multiple (five or more lesions) bilateral liver metastases. This series reports on longterm results after cryotherapy and hepatic arterial chemotherapy with or without liver resection in 224 patients with colorectal liver metastases, especially in patients with multiple bilateral liver disease, and identifies important prognostic determinants for survival.

STUDY DESIGN

A longterm retrospective analysis was performed of prospectively collected clinical data of 224 patients with colorectal liver metastases who received cryotherapy and hepatic arterial chemotherapy with or without resection. Morbidity, mortality, recurrence, and survival rates were reported and Kaplan-Meier and Cox regression analysis were used to identify prognostic indicators.

RESULTS

Median length of followup was 26 months (range 1 to 130 months). Perioperative mortality rate was 0.4% and morbidity rate was 21%. Cryosite, remaining liver, and extrahepatic recurrence rates were 39%, 62%, and 67%, respectively. Median survival was 31 months (range 1 to 130 months) with 1-, 3-, and 5-year survival rates of 87%, 43%, and 23%, respectively. Ninety-one patients had five or more bilateral lesions. Median and 5-year survival was 31 months (2 to 88 months) and 26%, respectively. Four factors were independently associated with favorable survival outcomes: cryotherapy with resection, complete tumor eradication, low pre- and postoperative CEA levels.

CONCLUSIONS

Cryotherapy and hepatic arterial chemotherapy with or without resection can achieve long survival advantage in patients with unresectable colorectal liver metastases.

Surgical strategies for colorectal liver metastases

Colorectal cancer remains the second commonest cause of death from cancer in Western society. Nearly half of all patients will develop liver metastases and many will die with disease confined to the liver. The accepted modern definitions of resectability now mean that over twenty per cent of patients are now resectable (with operative mortality of >2%) with curative intent, and nearly one third will be alive, disease free, five years later. The use of additional techniques such as radiofrequency ablation may bring many more patients the possibility of long term survival. The introduction of new chemotherapy regimens, including those based on oxaliplatin may convert one third of non-resectable patients to resectability with curative intent. Therefore, in 2004 nearly one third of patients with disease confined to the liver can now look forward to possibly curative liver surgery.

An analysis of newspaper reports of cancer breakthroughs: hope or hype?

OBJECTIVE

To assess the importance of cancer "breakthroughs" reported in the popular media 10 years after their publication.

STUDY DESIGN

Questionnaire-based survey in 2003 of expert opinion on the importance of all alleged cancer "breakthroughs" in cancer research or treatment reported in news articles in The Sydney Morning Herald between 1992 and 1994.

MAIN OUTCOME MEASURES

Assessment of each "breakthrough" by an expert in the relevant cancer subspecialty on seven measures of current importance.

RESULTS

31 unique reports of alleged cancer "breakthroughs" were identified, and experts responded to questionnaires on 30. Thirteen of these 30 reports (43%) were judged as not having been supported by further research in the following decade, with three (10%) having been refuted, while 16 (53%) were judged to remain potential breakthroughs, but more research was required. Eight "breakthroughs" (27%) had, or would soon be, incorporated into practice.

CONCLUSION

Cancer research findings reported in newspapers as "breakthroughs" are often not true breakthroughs but may be important for ongoing research. Consumers are likely to be receiving an overly optimistic picture of progress in understanding and treating cancer.

Interstitial ablative techniques for hepatic tumours

BACKGROUND

Most patients with liver tumours are not suitable for surgery but interstitial ablative techniques may control disease progression and improve survival rates.

METHODS

A review was undertaken using Medline of all reported studies of cryoablation, radiofrequency ablation, microwave ablation, interstitial laser photocoagulation, high-intensity focused ultrasound and ethanol ablation of primary liver tumours and hepatic metastases.

RESULTS

Although there are no randomized clinical trials, cryoablation, thermal ablation and ethanol ablation have all been shown to be associated with improved palliation in patients with primary and secondary liver cancer. The techniques can be undertaken safely with minimal morbidity and mortality.

CONCLUSION

Although surgical resection remains the first line of treatment for selected patients with primary and secondary liver malignancies, interstitial ablative techniques are promising therapies for patients not suitable for hepatic resection or as an adjunct to liver surgery.

Arterial chemotherapy as adjuvant and palliative treatment of hepatic colorectal metastases: an update

Regional hepatic chemotherapy with FUDR significantly improves local recurrence rates and may impact overall survival in patients with hepatic colorectal metastases. The results of prospective randomized trials confirm that careful patient selection, a thorough knowledge of intricate hepatic arterial anatomy, and an understanding of the pharmacokinetics and delivery of FUDR optimize treatment efficacy. A multimodality approach that includes adjuvant therapy in addition to cytoreductive surgery offers promise for the treatment of unresectable hepatic metastases. Because many tumors recur in extrahepatic sites, the addition of novel systemic agents such as CPT-11 may further reduce recurrences. Molecular analysis of the tumor may ultimately help select patients who are good candidates for regional chemotherapy.

Cryotherapy in the treatment of liver metastases from colorectal cancer

Although hepatic resection remains the treatment of choice for metastatic disease to the liver from colorectal cancer, the procedure is only possible for approximately 10% of patients. Ninety percent of patients with liver metastases ultimately die of liver failure. Thus, attention has turned to other, locoregional techniques that may be used alone or in conjunction with resection to increase the eligibility for some type of surgical, potentially curative treatment. One such option is cryotherapy. This review provides technical, physiologic, and outcome information regarding this technique. Semin Oncol 29:183-191.

Systemic irinotecan and regional floxuridine after hepatic cytoreduction in 185 patients with unresectable colorectal cancer metastases

BACKGROUND

This study evaluated our 7-year experience treating unresectable colorectal cancer (CRC) hepatic metastases refractory to systemic 5-fluorouracil.

METHODS

A total of 185 patients with unresectable 5-fluorouracil-resistant CRC hepatic metastases underwent surgical cytoreduction. Postoperatively patients received either hepatic arterial floxuridine (FUDR) and systemic irinotecan as part of a phase II trial or no further treatment.

RESULTS

Of the 185 patients undergoing surgical cytoreduction, 71 patients received adjuvant irinotecan/FUDR. There were no appreciable differences in synchronous or metachronous lesions or the median number or size of lesions between treatment groups. At a median follow-up of 20 months, there were fewer recurrences in patients treated with postoperative irinotecan/FUDR compared with untreated patients for both hepatic and extrahepatic recurrences. Progression-free and overall survival were longer for patients who received irinotecan/FUDR compared with patients who did not receive adjuvant therapy. The 2-year survival rate was significantly better for patients receiving adjuvant therapy compared with patients receiving no additional treatment. Predictors of improved survival included a preoperative carcinoembryonic antigen level <100 ng/dl, >30% postoperative reduction in carcinoembryonic antigen level, and adjuvant therapy.

CONCLUSIONS

Combined therapy with irinotecan/FUDR may improve the results of surgical cytoreduction for unresectable CRC hepatic metastases.

Electrolysis and other local ablative treatments for non-resectable colorectal liver metastases

The present paper is a review of the current ablative treatment options for the treatment of colorectal liver metastases. Cryotherapy, microwave coagulation therapy, radiofrequency ablation and laser-induced thermotherapy are discussed. Electrolysis, a novel non-thermal ablative treatment, is described. Potential benefits of electrolysis include the apparent ability to safely and effectively treat lesions abutting major hepatic structures and the lack of a systemic inflammatory reaction following electrolytic ablation. Further studies in animals and humans are needed to confirm this potential and to further refine the methods of electrolytic treatment of colorectal liver metastases.

Randomised trial of SIR-Spheres plus chemotherapy vs. chemotherapy alone for treating patients with liver metastases from primary large bowel cancer

PURPOSE

SIR-Spheres are radioactive yttrium90 microspheres (SIR-Spheres, Sirtex Medical Limited, Australia) used to selectively target high levels of ionising radiation to tumors within the liver. This trial was designed to measure any increased patient benefit by adding a single administration of SIR-Spheres to a regimen of regional hepatic artery chemotherapy (HAC) administered as a 12 day infusion of floxuridine and repeated at monthly intervals, vs. the same chemotherapy alone.

PATIENTS AND METHODS

A phase III randomised clinical trial entering 74 patients was undertaken on patients with bi-lobar non-resectable liver metastases from primary adenocarcinoma of the large bowel. Patient benefit criteria assessed in the trial were tumor response, time to disease progression in the liver, overall survival, quality of life, and treatment related toxicity. Tumor response was measured by serial changes in both cross-sectional tumor areas and total tumor volumes, provided any response lasted not less than three months as well as changes in serum carcino-embryonic antigen (CEA).

RESULTS

The partial and complete response rate (PR + CR) was significantly greater for patients receiving SIR-Spheres when measured by tumor areas (44%) vs. 17.6%, P = 0.01) tumor volumes (50% vs. 24%, P = 0.03) and CEA (72% vs. 47%, P = 0.004). The median time to disease progression in the liver was significantly longer for patients receiving SIR-Spheres in comparison to patients receiving HAC alone when measured by either tumor areas (9.7 vs. 15.9 months, P = 0.001), tumor volumes (7.6 vs. 12.0 months, P = 0.04) or CEA (5.7 vs. 6.7 months, P = 0.06). The one, two, three and five-year survival for patients receiving SIR-Spheres was 72%, 39%, 17% and 3.5%, compared to 68%, 29%, 6.5% and 0% for HAC alone. Cox regression analysis suggests an improvement in survival for patients treated with SIR-Spheres who survive more than 15 months (P = 0.06). There was no increase in grade 3-4 treatment related toxicity and no loss of quality of life for patients receiving SIR-Spheres in comparison to patients receiving HAC alone.

CONCLUSION

The combination of a single injection of SIR-Spheres plus HAC is substantially more effective in increasing tumor responses and progression free survival than the same regimen of HAC alone.

Systemic irinotecan or regional floxuridine chemotherapy prolongs survival after hepatic cryosurgery in patients with metastatic colon cancer refractory to 5-fluorouracil

Most colorectal cancers metastatic to the liver are resistant to chemotherapy and are not amenable to surgical resection. This study evaluated our 6-year experience (July 1992-July 1998) in treating patients with unresectable hepatic colorectal metastases refractory to systemic 5-fluorouracil (5-FU). One hundred fifty-three patients underwent cryosurgical ablation (CSA) of 5-FU-resistant hepatic metastases. The patients then received either hepatic arterial floxuridine (FUDR), systemic CPT-11, or no postoperative adjuvant chemotherapy. Number, size, and location of hepatic metastases, carcinoembryonic antigen (CEA) levels, and type of postoperative treatment were analyzed. One to 15 lesions were frozen (median number, 3; median size, 6 cm), for a total of 73 synchronous and 80 metachronous lesions. Overall median survival was 28.4 months from the date of diagnosis of liver metastases and 16.1 months from the time of CSA. After cryosurgery alone, median survival was 13 months, which was significantly shorter than the post-CSA survival of 23.6 months with adjuvant CPT-11 and 21.2 months with hepatic FUDR (P = 0.007). Predictors of survival included preoperative CEA, postoperative reduction in CEA, and adjuvant chemotherapy (P < 0.05). Neither size, number of lesions, nor tumor location impacted survival. At a median follow-up of 13 months, 67% of patients have recurred (35% hepatic, 16% extrahepatic, and 49% both). Twenty percent of the recurrences were in the lobe of the CSA site. The 25 patients who underwent a second CSA had a median survival of 28.4 months from CSA and 40 months from the date of diagnosis of liver metastases. These data indicate that CSA offers an effective alternative for unresectable patients resistant to 5-FU. Systemic CPT-11 or regional FUDR may further prolong survival after CSA.

Resection with cryotherapy of colorectal hepatic metastases has the same survival as hepatic resection alone

BACKGROUND

Hepatic resection is well established as a potentially curative treatment for hepatic colorectal cancer metastases. However, only a small proportion of patients with liver metastases are suitable for resection because they either have extrahepatic disease, or the extent and/or the distribution of their hepatic disease would make excision impossible. We have previously described the use of cryotherapy for inadequate resection margins and lesions in the remaining lobe of the liver. Combining such cryodestructive techniques with resection offers the possibility of increasing the proportion of patients to whom potentially curative treatment can be offered. The aim of this study was to compare survival in patients treated with resection and cryotherapy against those of patients treated with resection alone. Potential prognostic variables were also examined.

METHOD

Patients undergoing a hepatic resection with or without cryotherapy at our unit between April 1990 and July 1997 were identified from our database and their notes reviewed. Survival was estimated using the Kaplan-Meier method and compared using the Log rank test.

RESULTS

One hundred and seven patients were treated in total: 32 underwent resection alone, and 75 underwent resection combined with cryotherapy. There was no significant difference between the survival of patients treated with resection alone and those treated with resection and cryotherapy.

CONCLUSIONS

Edge and contralobe cryotherapy can be combined with hepatic resection to allow a greater proportion of patients with hepatic colorectal metastases to be offered treatment, and results in similar survival figures comparable to hepatic resection for at least 3 years.

Indicators of recurrence following cryotherapy for hepatic metastases from colorectal cancer

BACKGROUND

This retrospective review aimed to assess the incidence of local recurrence at the cryosite, hepatic and extrahepatic recurrence and the corresponding disease-free intervals. Prognostic indicators following hepatic cryotherapy were also identified.

METHODS

Eighty-five patients underwent complete cryotreatment of colorectal liver metastases between April 1990 and May 1997. Possible prognostic indicators were tested for their impact on the disease-free interval at the cryosite, liver disease-free survival and overall disease-free survival with univariate and multivariate analysis.

RESULTS

At a median follow-up of 22 months 66 patients developed tumour recurrence: 18 in the liver only; 15 in the liver and lung; 22 in the liver and extrapulmonary areas; and 11 at extrahepatic sites only. Local recurrence at the cryosite occurred in 28 patients. Cryotreated metastases larger than 3 cm were associated with a shorter disease-free interval at the cryosite and liver disease-free survival; persistently raised serum carcinoembryonic antigen (CEA) levels after operation were associated with shorter liver disease-free and overall disease-free intervals in multivariate analysis.

CONCLUSION

Improvements in probe placement and monitoring of the freezing process are required to allow successful treatment of large liver metastases. A failure in complete postoperative CEA response indicates that hepatic or extrahepatic disease was not detected before operation, which may be avoided with better staging procedures.

Patterns of serum CEA fall after hepatic arterial chemotherapy as sole therapy and combined with cryotherapy for colorectal metastases

BACKGROUND

Hepatic artery chemotherapy (HAC) and cryoablation are treatments for unresectable liver metastases from colorectal carcinomas. Our centre has previously published data that describe survival statistics of patients after each of these treatments. It has also been established that serial serum carcinoembryonic antigen (CEA) concentrations may be used to monitor disease progress, and that the magnitude of fall is prognostic for both treatments. The pattern of fall of CEA following cryotherapy and regional chemotherapy has not previously been compared.

METHODS

In this study, we examined 26 HAC patients and 24 cryotherapy patients.

RESULTS

The mean percentage of the pre-treatment CEA concentration for the HAC group was 60.5% at 50 days and 29.4% at 150 days, and for the cryotherapy group 24.9% at 50 days and 24.3% at 150 days. Calculating the difference between means revealed a significantly different mean fall in the cryotherapy group at 50 days (P < 0.001) and a difference in mean fall at 150 days (P > 0.1) which was not significant. In patients who responded to hepatic artery chemotherapy, the eventual CEA fall was very similar in magnitude.

CONCLUSIONS

The pattern of fall of CEA differs in these two treatments.

Laparoscopic cryoablation of hepatic metastases

Cryosurgery for liver metastases may improve survival for unresectable hepatic metastases. The laparoscopic approach to managing these tumors is a novel method fostered by increasing surgeon and patient interest in minimally invasive surgical techniques and the development of laparoscopic ultrasound and cryoprobes. A retrospective review of our patients who underwent laparoscopic cryoablation of hepatic tumors from April 1996 to December 1997 was conducted. We report on this experience and comment on the feasibility and safety of the procedure based on this early trial.

Prognostic factors after cryotherapy for hepatic metastases from colorectal cancer

OBJECTIVE

To establish the prognostic importance of different patient and tumor characteristics in cryotherapy for liver metastases from colorectal cancer.

SUMMARY BACKGROUND DATA

Hepatic cryotherapy has been used as a treatment of nonresectable liver metastases from colorectal cancer in almost 1000 patients worldwide, and its safety and efficacy are well established. However, tumor eventually recurs in most patients and they die of their disease. The knowledge of prognostic factors would allow the selection of patients who are more likely to benefit from this treatment and patients who may need additional treatment.

METHODS

Between April 1990 and May 1997, 195 patients were treated with hepatic cryotherapy. Out of this group, the authors identified 116 patients with colorectal cancer who received cryotherapy for ablation of liver metastases. Survival was estimated with the Kaplan-Meier method, using the log-rank test for univariate analysis for significance of possible prognostic factors. For multivariate analysis, a Cox regression was used.

RESULTS

One patient (0.9%) died of postoperative myocardial infarction. The total perioperative morbidity rate was 27.6%. Median survival and the 5-year survival rate were 26 months and 13.4%. The following factors were identified as independently associated with a favorable outcome: low presurgical serum level of carcinoembryonic antigen (CEA), small (< or =3 cm) diameter of cryoablated metastases, absence of untreated extrahepatic disease at laparotomy, absence of nodal involvement at primary resection, complete cryotreatment, synchronous development of liver metastases, and good or moderate differentiation of the primary tumor. Although univariate analysis suggested a favorable prognosis in patients who did not receive blood transfusion during surgery and patients younger than 51 years, this was not confirmed in multivariate analysis. In addition, normalization of the serum CEA level after treatment was an important prognostic marker in the subgroup of patients with elevated serum CEA levels before surgery.

CONCLUSIONS

Hepatic cryotherapy is a safe and effective treatment option for patients with nonresectable liver metastases from colorectal cancer, with promising results regarding survival. The prognostic factors established in this series may allow better patient selection to improve the outcome in suitable patients.

Cryotherapy for neuroendocrine liver metastases

While the prognosis for patients with untreated liver metastases from neuroendocrine primaries is rather good, they often suffer disabling symptoms due to syndromes of hormonal excess. Thirteen patients with metastatic neuroendocrine tumours were treated by hepatic cryotherapy; seven patients were symptomatic and five of these had elevated levels of hormonal tumour markers. Twelve patients are alive and mostly asymptomatic with a median follow up of 13.5 months; one patient died after 45 months of bronchopneumonia without evidence of tumour recurrence. All patients with elevated preoperative tumour markers have had a significant fall in markers postoperatively. Two patients were returned to the operating theatre for coagulopathy-associated bleeding: one patient each developed acute renal failure and pulmonary embolism, but there was no mortality. This study shows that hepatic cryotherapy offers a useful treatment option for this group of patients, alleviates symptoms and may have an impact on survival.

Treatment of colorectal liver metastases by cryotherapy

One hundred fifty-eight procedures were performed on 136 patients with unresectable hepatic metastases using hepatic cryotherapy to ablate the tumors. The median age was 62 years. Patients included 90 males and 46 females. Fifty-eight patients had synchronous metastases, 55 had bilobar lesions, and 90 had precryo chemotherapy. Median preoperative carcinoembryonic antigen (CEA) level was 14.4 ng/dl. The numbers of lesions treated, frozen, and resected were two and one. Median survival of all patients was 30 months. Survival for 39 patients was 37 months. Patients with a CEA level > 100 ng/dl had a statistically worse survival rate than those with a level < 100 ng/dl (P < .001). Twenty patients underwent recryotherapy with median survival of 34 months. Recurrent disease developed in 78% of patients--82% of the patients developed liver recurrence. Complication rates were comparable to liver resection. Operative mortality was 3.7%. Hepatic cryotherapy is effective and safe in treating colorectal hepatic metastases under ultrasound guidance.

Biochemical, hematologic, and immunologic alterations following hepatic cryotherapy

Hepatic cryosurgery causes hepatocellular damage primarily by inducing the formation of ice crystals. Cell necrosis is enhanced using two or more freeze-thaw cycles. The resultant damage to hepatocytes induces alterations in a number of biochemical and hematologic parameters, including hepatic function tests, serum bilirubin, serum and urine myoglobin, platelet count, and coagulation measures. Further, in experimental models, cryogenic surgery appears to stimulate the immune system of the host leading to an anti-tumor immune response. These perturbations in biochemical and hematologic parameters are usually transient, and long-term adverse sequelae are uncommon and preventable.

High serum carcinoembryonic antigen concentration in patients with colorectal liver metastases is associated with poor cell-mediated immunity, which is predictive of survival

BACKGROUND

Carcinoembryonic antigen (CEA) inhibits lymphocyte function and patients with cancer have lower cell-mediated immunity (CMI) than the normal population. To test this association an investigation was made of the relationship between CMI score, CEA level and survival.

METHODS

CEA level, CMI score and other variables were compared with the survival time of 109 patients with colorectal liver metastases using Cox regression analysis.

RESULTS

There was a significant association between CMI and CEA categories (P = 0.04, chi 2 test). The odds of patients with normal CMI having a CEA level in the upper quartile observed for all patients were 22 per cent of those of patients with depressed CMI (odds ratio 0.22 (95 per cent confidence interval (c.i.) 0.03-0.90), mid-P corrected). The median survival time of patients with normal CMI scores was 943 days compared with 488 days for those with depressed CMI (P = 0.03, log rank test; P = 0.04, Peto). The mortality risk of patients with normal CMI at entry to the study was, in the first 2 years of treatment, 40 per cent of that of patients with depressed CMI (95 per cent c.i. for relative risk 0.20-0.82, Cox regression).

CONCLUSION

In patients with colorectal hepatic metastases, CMI is predictive of survival and a raised serum CEA level is associated with depressed CMI.

Management strategies for colorectal liver metastases--Part II

Liver metastases are relatively common in colorectal cancer and a small proportion of patients may benefit from resection of these liver metastases. In a selected subgroup of patients, 5-year survival rates of 25-35% may be achieved following liver resection. These survival figures compare favourably with those of patients with untreated liver secondaries. In the second part of this review the surgical and non-surgical treatment options for treating colorectal liver metastases are examined in detail.

Previous intravenous chemotherapy does not alter response rate or survival time of patients with hepatic metastases from colorectal cancer treated by hepatic artery chemotherapy

BACKGROUND

The present paper addressed the issue of whether pretreatment with intravenous (i.v.) chemotherapy affects response rate or survival in patients receiving hepatic artery chemotherapy (HAC).

METHODS

Case note reviews of 164 patients treated in a teaching hospital from June 1990 to July 1996 were carried out.

RESULTS

The response rate and carcino-embryonic antigen (CEA) fall in the two groups was almost identical. There was a nonsignificant survival advantage in the non-pretreatment group.

CONCLUSIONS

Previous administration of i.v. chemotherapy did not affect the CEA response of patients receiving HAC.

Cryotherapy treatment of patients with hepatic metastases from neuroendocrine tumors

BACKGROUND

Liver metastases from neuroendocrine tumors often present with disabling symptoms due to syndromes of hormonal excess. A locally destructive technique such as hepatic cryotherapy not only alleviates symptoms but may improve survival in this group of patients.

METHODS

Six patients with metastatic neuroendocrine tumors were treated with hepatic cryotherapy. Four patients were symptomatic and three of these had elevated tumor markers from ectopic hormone production.

RESULTS

All patients are alive and asymptomatic, with a median follow-up of 24 months (range, 6 months to 6 years). All have had a complete radiologic response. All with elevated preoperative markers have had a greater than 89% decrease in tumor markers. Coagulopathy occurred in two patients necessitating additional surgery, but there was no other morbidity attributable to the cryotherapy.

CONCLUSION

To the authors' knowledge, this study demonstrates for the first time that hepatic cryotherapy offers supportive treatment for patients with neuroendocrine tumors metastatic to the liver. Cryotherapy alleviates symptoms and may improve survival.