Lymphadenectomy in colorectal cancer liver metastases resection: incidence of hilar lymph nodes micrometastasis

Prediction of hepatic lymph node metastases based on magnetic resonance imaging before and after preoperative chemotherapy in patients with colorectal liver metastases underwent surgical resection

BACKGROUND

Patients with colorectal liver metastases (CRLM) combined with hepatic lymph node (HLN) metastases have a poor prognosis. In this study, we developed and validated a model using clinical and magnetic resonance imaging (MRI) parameters to predict HLN status before surgery.

METHODS

A total of 104 CRLM patients undergoing hepatic lymphonodectomy with pathologically confirmed HLN status after preoperative chemotherapy were enrolled in this study. The patients were further divided into a training group (n = 52) and a validation group (n = 52). The apparent diffusion coefficient (ADC) values, including ADC_mean and ADC_min of the largest HLN before and after treatment, were measured. rADC was calculated referring to the target liver metastases, spleen, and psoas major muscle (rADC_-LM, rADC_-SP, rADC_-m). In addition, ADC change rate (Δ% ADC) was quantitatively calculated. A multivariate logistic regression model for predicting HLN status in CRLM patients was constructed using the training group and further tested in the validation group.

RESULTS

In the training cohort, post-ADC_mean (P = 0.018) and the short diameter of the largest lymph node after treatment (P = 0.001) were independent predictors for metastatic HLN in CRLM patients. The model's AUC was 0.859 (95% CI, 0.757-0.961) and 0.767 (95% CI 0.634-0.900) in the training and validation cohorts, respectively. Patients with metastatic HLN showed significantly worse overall survival (p = 0.035) and recurrence-free survival (p = 0.015) than patients with negative HLN.

CONCLUSIONS

The developed model using MRI parameters could accurately predict HLN metastases in CRLM patients and could be used to preoperatively assess the HLN status and facilitate surgical treatment decisions in patients with CRLM.

Intrahepatic lymphatic invasion but not vascular invasion is a major prognostic factor after resection of colorectal cancer liver metastases

BACKGROUND

Despite advances in diagnosis and surgical strategies, up to 70% of patients will develop recurrence of the disease after resection of colorectal cancer liver metastases (CRCLM). The purpose of our study was to determine the frequency of four different mechanisms of intrahepatic dissemination, and to evaluate the impact of each mechanism on patient outcomes.

METHODS

The medical records of 118 patients who underwent a first resection of CRCLM during the period between 2000 and 2010 were reviewed. Clinicopathologic variables and outcome parameters were examined. Resected specimens were submitted to routine histological evaluation, and immunohistochemical staining with D2-40 (lymphatic vessels), CD34 (blood vessels), CK-7 (biliary epithelium), and CK-20 (CRC cells).

RESULTS

The mean follow-up after resection was 38 months. Tumor recurrence was observed in 76 patients, with a median interval of 13 months after resection. Overall survival and disease-free survival (DFS) rates after hepatectomy were 62 and 56%, and 26 and 24% at 3 and 5 years, respectively. Intrahepatic microscopic invasion included portal venous in 49 patients, sinusoidal in 43 patients, biliary in 20 patients, and lymphatic in 33 patients. Intra-hepatic lymphatic invasion was the only mechanism of dissemination independently associated with the risk of hepatic recurrence (odds ratio 2.75) and shorter DFS (p = 0.006).

CONCLUSION

Intrahepatic lymphatic invasion is a significant prognostic factor. Other mechanisms of invasion, although frequently observed, are not related to recurrence or survival, suggesting that the lymphatic system is the main route for dissemination of CRCLM. Furthermore, immunohistochemical detection of intrahepatic lymphatic invasion might be of value in clinical practice.

Surgical outcomes and prognostic factors in patients with synchronous colorectal liver metastases

CONTEXT

Colorectal cancer is the second most prevalent cancer worldwide, and the liver is the most common site of metastases. Surgical resection of colorectal liver metastases provides the sole possibility of cure and the best odds of long-term survival. Objectives To describe surgical outcomes and identify features associated with disease prognosis in patients submitted to synchronous colorectal cancer liver metastasis resection.

METHODS

Retrospective study of 59 patients who underwent surgery for synchronous colorectal cancer liver metastasis. Actuarial survival and disease-free survival were assessed, depending on the prognostic variable of interest.

RESULTS

Postoperative mortality and morbidity rates were 3.38% and 30.50% respectively. Five-year disease-free survival was estimated at 23.96%, and 5-year overall survival, at 38.45%. Carcinoembryonic antigen levels ≥ 50 ng/mL and presence of three or more liver metastasis were limiting factors for disease-free survival, but did not affect late survival. No patient with liver metastases and extrahepatic disease had disease-free interval longer than 20 months, but this had no significance or impact on long-term survival. None of the prognostic factors assessed had an impact on late survival, although no patients with more than three liver metastases survived beyond 40 months.

CONCLUSIONS

Although Carcinoembryonic antigen levels and number of metastases are prognostic factors that limit disease-free survival, they had no impact on 5-year survival and, therefore, should not determine exclusion from surgical treatment. Resection is the best treatment option for synchronous colorectal liver metastases, and even for patients with multiple metastases, large tumors and extrahepatic disease, it can provide long-term survival rates over 38%.

Lymphatic drainage of the liver and its implications in the management of colorectal cancer liver metastases

The liver is the most common site of distant metastases in patients with colorectal cancer. Surgery represents the mainstream for curative treatment of colorectal cancer liver metastases (CRCLM) with long-term survival up to 58 and 36 % at 5 and 10 years, respectively. Despite advances on diagnosis, staging and surgical strategies, 60-70 % of patients will develop recurrence of the disease even after R0 resection of CRCLM. Tumor staging, prognosis, and therapeutic approaches for cancer are most often based on the extent of involvement of regional lymph nodes (LNs) and, to a lesser extent, on the invasion of regional lymphatic vessels draining the primary tumor. For CRCLM, the presence of intra hepatic lymphatic and blood vascular dissemination has been associated with an increased risk of intra hepatic recurrence, poorer disease-free and overall survival after liver resection. Also, several studies have reviewed the role of surgery in the patient with concomitant CRCLM and liver pedicle LN metastasis. Although pedicle LN involvement is related to worst survival rates, it does not differentiate patients that will relapse from those that will not. This review aims to briefly describe the anatomy of the liver's lymphatic drainage, the incidence of intrahepatic lymphatic invasion and hilar lymph node involvement, as well as their clinical impact in CRCLM. A better understanding of the role of liver lymphatic metastasis might, in the near future, impact the strategy of systemic therapies after liver resection as for primary colorectal tumors.

Lymphatics and colorectal liver metastases: the case for sentinel node mapping

BACKGROUND

Hepatic resection remains the treatment of choice for patients with colorectal liver metastases (CLM). Indications for hepatic resection have been extended to include extrahepatic lymph node groups, resulting in increased survival benefits. The identification of specific lymph pathways and involved nodes is necessary to support the development of guidelines for a more focused approach to the management of this disease. The feasibility of sentinel node mapping should be investigated to define specific lymphatic groups involved in CLM.

METHODS

Scientific papers published from 1950 to 2012 were sought and extracted from the MEDLINE, PubMed and University of Melbourne databases.

RESULTS

Several studies have reported microscopic lymph node involvement in 10-15% of patients undergoing hepatic resection for CLM in which no macroscopic involvement was evident. In retrospect, over 80% of lymphadenectomies are proven unnecessary. Traditional imaging modalities have limited predictive value in detecting lymph node involvement. Sentinel node mapping has proved an extremely accurate tool in detecting lymph node involvement and can identify patients in whom lymphadenectomy may be beneficial.

CONCLUSIONS

Current imaging techniques are inadequate to detect microscopic lymph node involvement in patients with resectable CLM. The use of sentinel node mapping is proposed to identify nodal groups involved and provide management strategies.

Surgery for colorectal liver metastases

Half of all patients with colorectal cancer develop metastatic disease. The liver is the principal site for metastases, and surgical resection is the only modality that offers the potential for long-term cure. Appropriate patient selection for surgery and improvements in perioperative care have resulted in low morbidity and mortality rates, resulting in this being the therapy of choice for suitable patients. Modern management of colorectal liver metastases is multimodal incorporating open and laparoscopic surgery, ablative therapies such as radiofrequency ablation or microwave ablation and (neo)adjuvant chemotherapy. The majority of patients with hepatic metastases should be considered for resectional surgery, if all disease can be resected, as this offers the only opportunity for prolonged survival.

Long-term survival after hepatic and pulmonary resection of colorectal cancer metastases

BACKGROUND

Recent changes in adjuvant therapies improved the prognosis of metastatic colorectal cancers. Curative resection may be considered, even for both pulmonary and hepatic metastases, but prognostic factors are not well identified.

METHODS

From 1995 to 2010, 69 patients had curative resection of pulmonary metastases of colorectal cancer; 31 had also hepatic metastases. Pulmonary and hepatic resection occurred in 2 steps (87%). We studied overall and disease-free survival and prognostic factors.

RESULTS

Primary tumor location was the rectum in 10 cases (32%). Pulmonary metastases were synchronous in 5 (16%) and bilateral in 6 (19%). One patient (3%) died after pulmonary surgery. One (3%) had positive surgical margins for pulmonary metastases. Median overall survival was 44 months (5-year rate = 36%); median disease-free survival was 22 months (5-year rate = 10%). Factors linked to impaired survival were rectal primary tumor (P = 0.04) and bilateral pulmonary metastases (P = 0.02) for overall survival, and pulmonary metastase ≥ 20 mm (P = 0.04) for disease-free survival.

CONCLUSION

When associated to adjuvant therapy, complete resection of pulmonary and hepatic metastases of colorectal cancer allows long-term survival in one third of the patients.

The role of hilar lymphadenectomy in patients subjected to hepatectomy due to colorectal metastasis

CONTEXT

Hepatectomy is the treatment of choice for colorectal liver metastases, and several studies have shown good results, with 5-year survival rates ranging from 40% to 57%. Several clinical and pathological predictive factors for survival after liver resection have been studied. Involvement of the hepatic hilum lymph nodes, the incidence of which varies from 2% to 10%, indicates a poor long-term prognosis.

RESULTS

Despite variable results, some authors have reported a not-insignificant improvement in survival rate in liver-metastasis patients with hilar lymph node involvement who undergo combined liver resection and lymphadenectomy. Due to the low rates of morbidity and mortality for liver-resection surgery, several specialized centers perform liver resections combined with lymphadenectomies in selected cases. It should be noted that the therapeutic value of systemic lymphadenectomy is not yet entirely understood, and only controlled studies comparing groups with and without lymphadenectomy can fully resolve the issue.

CONCLUSION

In any case, hilar lymph node dissection has been shown to be a useful tool for improving the accuracy of extra hepatic disease staging, regardless of its impact on survival.

Current state of surgical treatment of liver metastases from colorectal cancer

Hepatic resection is the procedure of choice for curative treatment of colorectal liver metastases (CLM). Objectives of surgical strategy are low intraoperative blood loss, short liver ischemic times and minor postoperative morbidity and mortality. Blood loss is an independent predictor of mortality and compromises, in common with postoperative complications, long-term outcome after hepatectomy for CLM. The type of liver resection has no impact on the outcome of patients with CLM; wedge resections are not inferior to anatomical resections in terms of tumor clearance, pattern of recurrence or survival. Despite the lack of proof of survival benefit, routine lymphadenectomy has been advocated, allowing the detection of microscopic lymph node metastases and with prognostic value. In experienced hands, minimally invasive liver surgery is safe with acceptable morbidity and mortality and oncological results comparable to open hepatic surgery, but with reduced blood loss and earlier recovery. The European Colorectal Metastases Treatment Group recommended treating up front with chemotherapy for patients with both resectable and unresectable CLM. However, neoadjuvant chemotherapy can induce damage to the remnant liver, dependent on the number of chemotherapy cycles. Therefore, in our opinion, preoperative chemotherapy should be reserved for patients whose CLM are marginally resectable or unresectable. A meta analysis of randomized trials dealing with perioperative chemotherapy for the treatment of resectable CLM demonstrated a benefit of systemic chemotherapy but did not answer the question of whether a neoadjuvant or adjuvant approach should be preferred. Analysis of the literature demonstrates that the results of specialized centers cannot be attained in the reality of comprehensive patient care. Reasons behind the commonly poorer results seen in cancer networks as compared with literature-based data are, on the one hand, geographical disparities in access to specialized surgical and medical care. On the other hand, a selection bias in the reports of the literature may be assumed. Studies of surgical resection for CLM derive almost exclusively from case series generally drawn from large academic centers where patient selection or surgical expertise is superior to what is found in many communities. Therefore, we may conclude that the comprehensive propagation of the standards outlined in this paper constitutes a major task in the near future to reduce the variations in survival of patients with CLM.

Hepatectomy and resection of concomitant extrahepatic disease for colorectal liver metastases--a systematic review

BACKGROUND

Recent data suggest that hepatectomy for patients with colorectal liver metastases (CLM) with concomitant extrahepatic disease (EHD) achieve encouraging survival result. The authors examine the clinical efficacy of this treatment approach through a systematic review of the published literature.

METHODS

Electronic search of the MEDLINE and PubMed databases (January 2000 to January 2011) to identify studies reporting outcomes of hepatectomy for CLM with resection of EHD was undertaken. Two reviewers independently appraised each study using a predetermined protocol. Clinical efficacy was synthesised through a narrative review with full tabulation of results of all included studies.

RESULTS

Twenty-two studies were examined. This comprised 1142 patients. The median disease-free survival was 12 (range, 4-22) months, median overall survival was 30 (range, 14-44) months and median 5-year survival rate was 19% (range, 0-42%). Median 5-year survival of patients with R0 hepatectomy with resection of EHD was 25% (range, 19-36%). Survival based on site of EHD include lung; median survival (M/S) was 41 (range, 32-46) months, porto-caval lymph node; M/S was 25 (range, 19-48) months, peritoneal metastases; M/S was 25 (range, 18-32) months.

CONCLUSION

In the era of effective systemic therapies, surgical resection of CLM and concomitant EHD in carefully selected patients may achieve survival results superior to non-surgically treated patients. This treatment strategy may be considered appropriate especially when a R0 hepatectomy and complete resection of EHD may be achieved.