Stage IV colon cancer denotes distant metastatic disease. Treatment of recurrent colon cancer depends on the sites of recurrent disease demonstrable by physical examination and/or radiographic studies. In addition to standard radiographic procedures, radioimmunoscintography may add clinical information that may affect management. Such approaches have not led to improvements in long-term outcome measures such as survival.
Treatment Options for Stage IV and Recurrent Colon Cancer
Treatment options for stage IV and recurrent colon cancer include the following:
- Surgical resection of locally recurrent cancer.
- Surgical resection and anastomosis or bypass of obstructing or bleeding primary lesions in selected metastatic cases.
- Resection of liver metastases in selected metastatic patients (5-year cure rate for resection of solitary or combination metastases exceeds 20%) or ablation in selected patients.[2,3,4,5,6,7,8,9,10,11]
- Resection of isolated pulmonary or ovarian metastases in selected patients.
- Palliative radiation therapy.
- Palliative chemotherapy.
- Targeted therapy.
- Clinical trials evaluating new drugs and biological therapy.
- Clinical trials comparing various chemotherapy regimens or biological therapy, alone or in combination.
Treatment of Liver Metastasis
Approximately 50% of colon cancer patients will be diagnosed with hepatic metastases, either at the time of initial presentation or as a result of disease recurrence. Although only a small proportion of patients with hepatic metastases are candidates for surgical resection, advances in tumor ablation techniques and in both regional and systemic chemotherapy administration provide for a number of treatment options. These include the following:
- Neoadjuvant chemotherapy.
- Local ablation.
- Adjuvant chemotherapy.
- Intra-arterial chemotherapy.
Hepatic metastasis may be considered to be resectable based on the following:[5,7,13,14,15,16]
- Limited number of lesions.
- Intrahepatic locations of lesions.
- Lack of major vascular involvement.
- Absent or limited extrahepatic disease.
- Sufficient functional hepatic reserve.
For patients with hepatic metastasis considered to be resectable, a negative margin resection resulted in 5-year survival rates of 25% to 40% in mostly nonrandomized studies, such as the NCCTG-934653 trial.[5,7,13,14,15,16] Improved surgical techniques and advances in preoperative imaging have allowed for better patient selection for resection. In addition, multiple studies with multiagent chemotherapy have demonstrated that patients with metastatic disease isolated to the liver, which historically would be considered unresectable, can occasionally be made resectable after the administration of chemotherapy.