Colorectal cancer--what is standard surgery?

Surgery for colorectal liver metastases: expanding the boundaries but where have all the patients gone

AIM

To review and discuss the current strategies and controversies in the surgical management of colorectal cancer liver metastases.

METHODS

An analysis of indications, contraindications and scoring systems and concepts for expanding the indications for resection are discussed. The findings and discussion are related to our own experience, especially with radiofrequency assisted liver resection for colorectal cancer liver metastases.

RESULTS

Resection is the only management strategy that can potentially cure the patient. Certain controversies still exist, such as contraindications for surgery, timing of treatment of synchronous metastases, significance of extra-hepatic disease etc. Strategies that can improve respectability are discussed. Parenchyma oriented, tissue sparing surgery facilitates reresection should it become necessary.

CONCLUSION

The management of colorectal cancer liver metastases is still a confusing issue for general oncologists and general surgeons. A multidisciplinary approach that tailors the management strategy to the individual patient is the only option that provides optimal results for patients with advanced disease.

Colorectal cancer follow-up: Useful or useless?

Follow-up of surgically treated colorectal cancer patients is not supported by objectively certain data. Despite the thousands of investigations reported in the scientific literature, only six randomized prospective studies and two meta-analysis of randomized studies provide data suggesting clear conclusions. Our review of the literature revealed that intensive colorectal follow-up should be performed even if the long-term survival benefit is small. The timing and investigations conducted in follow-ups diverge. The inconsistency of follow-ups is revealed by the fact that the leading USA and European societies propose different guidelines. One datum that the literature agrees on is that pancolonoscopy performed at 3-5 year intervals in colorectal cancer surgery patients supports diagnosis of adenomatous polyps and metachronous cancers. Cost analysis have shown that intensive follow-up would certainly exceed the cut-off point level set for every additional year of good quality of life.

OncoSurge: a strategy for improving resectability with curative intent in metastatic colorectal cancer

PURPOSE

Most patients with colorectal liver metastases present to general surgeons and oncologists without a specialist interest in their management. Since treatment strategy is frequently dependent on the response to earlier treatments, our aim was to create a therapeutic decision model identifying appropriate procedure sequences.

METHODS

We used the RAND Corporation/University of California, Los Angeles Appropriateness Method (RAM) assessing strategies of resection, local ablation and chemotherapy. After a comprehensive literature review, an expert panel rated appropriateness of each treatment option for a total of 1,872 ratings decisions in 252 cases. A decision model was constructed, consensus measured and results validated using 48 virtual cases, and 34 real cases with known outcomes.

RESULTS

Consensus was achieved with overall agreement rates of 93.4 to 99.1%. Absolute resection contraindications included unresectable extrahepatic disease, more than 70% liver involvement, liver failure, and being surgically unfit. Factors not influencing treatment strategy were age, primary tumor stage, timing of metastases detection, past blood transfusion, liver resection type, pre-resection carcinoembryonic antigen (CEA), and previous hepatectomy. Immediate resection was appropriate with adequate radiologically-defined resection margins and no portal adenopathy; other factors included presence of < or = 4 or > 4 metastases and unilobar or bilobar involvement. Resection was appropriate postchemotherapy, independent of tumor response in the case of < or = 4 metastases and unilobar liver involvement. Resection was appropriate only for > 4 metastases or bilobar liver involvement, after tumor shrinkage with chemotherapy. When possible, resection was preferred to local ablation.

CONCLUSION

The results were incorporated into a decision matrix, creating a computer program (OncoSurge). This model identifies individual patient resectability, recommending optimal treatment strategies. It may also be used for medical education.

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.

OncoSurge: a strategy for long-term survival in metastatic colorectal cancer

OncoSurge is a combined modality strategy for the management of colorectal cancer with hepatic metastases. It has emerged as a result of new and expanded patient selection criteria for resectability of metastases, coupled with more effective neoadjuvant and postoperative chemotherapy. By bringing together these developments in surgery and medical oncology, the new approach promises to increase significantly the resectability rate and long-term survival in colorectal cancer patients with liver metastases. Surgery for colorectal liver metastases should now be considered across a range of clinical circumstances that would historically have been contraindications to resection. These contraindications include multiple or bilobar metastases, large tumour size, a Dukes stage C or poorly differentiated primary tumour, synchronous detection of metastases with the primary tumour, disease in elderly patients, or a resection margin of less than 1 cm. None of these criteria should necessarily exclude a patient from resection, because although they may be associated with a less favourable prognosis they do not exclude the possibility of long-term survival. Non-resectable extrahepatic disease and portal lymph node involvement, however, remain contraindications to resection in most circumstances. Retrospective studies of neoadjuvant therapy have indicated that a regimen based on low dose oxaliplatin, 5-fluorourucil (5-FU) and leucovorin increased the overall resectability rate of patients presenting with hepatic colorectal metastases from 20% to 30%, with 13.6% of patients with unresectable metastases becoming eligible for curative resection. More recently, studies using more potent oxaliplatin-based regimens have reported significantly higher resectability rates of at least 40%, with 5-year survival of 50% reported in one large study among patients whose liver metastases were resected after initial neoadjuvant therapy for unresectable tumours. Following resection, postoperative therapy based on a combination of hepatic artery infusion (HAI) and systemic chemotherapy reduces hepatic recurrence and increases survival, but more potent systemic therapy is required to reduce the rate of extrahepatic recurrence. Studies are now in progress combining HAI with oxaliplatin-based systemic therapy to address this issue. By combining a more inclusive approach to surgery with more effective neoadjuvant and postoperative chemotherapy, the OncoSurge treatment model is likely to increase significantly the number of patients with hepatic colorectal metastases who can be treated with curative intent, and thus has the potential to improve overall patient survival.

Radio (chemo) therapy in locally advanced rectal cancer

Radiotherapy has an role in combined treatment to lower local recurrence in resectable rectal cancer. Radiotherapy also has an established role in nonresectable rectal cancers to increase the operability, but radiochemotherapy is more efficient. Radiotherapy can be administered as a transcutaneous therapy on the megavoltage machines as well as brachytherapy and combined--transcutaneous and brachytherapy.