Colorectal cancer adjuvant chemotherapy

Adjuvant therapy differs for colon and rectal cancer because their natural history and recurrence patterns differ. Rectal cancer is more difficult to resect with wide margins, so local recurrences are more frequent than with colon cancer. Adjuvant RT plus chemotherapy is considered standard for stage 11 or 111 rectal cancer. Adjuvant chemotherapy is standard for stage 111 colon cancer and can be considered for high-risk stage II colon cancer. Adjuvant therapy is not indicated for stage I colorectal cancer because most patients are cured by surgical resection alone. 

Fluorouracil-based chemotherapy is the standard of care for the adjuvant treatment of colorectal cancer either as a single agent or, more commonly, in combination with other agents. 5-Fluorouracil (5-FU) alone results in a small improvement in survival that can vary based on the method of 5-FU administration. Studies suggest that protracted or continuous intravenous (IV) 5-FU infusion treatment schedules are more effective than bolus therapy.20... 

Chemotherapy Regimens for the Adjuvant Treatment of Colorectal Cancer... 

Human cancers vary widely in their ability to produce metastasis. At present, there are no reliable methods to predict metastatic potential. For optimum patient management, however, knowledge of the aggressiveness of a tumor is desirable when deciding which patients should receive adjuvant chemotherapy. This type of information is particularly important for axillary node-negative breast cancer and Dukes B colorectal cancer. 

Colorectal cancer is the third most common cancer and the second leading cause of cancer-related deaths in the United States. (77). The incidence is approx. 40 per 100,000 in men and 25-30 per 100,000 in women (78). For those with stage 111 disease with presumed micrometastatic disease, adjuvant chemotherapy is used, typically 5-fluorouracil (5-FU) and leucovorin for 6-8 mo, with a 30% reduction in disease recurrence and 22-32% reduction in mortality (79,80). 

Chemotherapy and radiation therapy play an important role in the management of colorectal carcinoma. Significant improvements in tumor control and overall survival have been demonstrated with the use of combined-modality therapy in several randomized clinical trials performed over the past 25 yr. This chapter reviews the role of adjuvant chemotherapy and radiation therapy for colon and rectal cancer. Issues surrounding chemoradiation for rectal cancer, including sphincter preservation, total mesorectal excision, local excision, and newer chemotherapy agents, are also discussed. 

Elsaleh H, Joseph D, Grieu F, et al. Association of tumour site and sex with survival benefit from adjuvant chemotherapy in colorectal cancer. Lancet 2000 355(9217) 1745-1750. 

Adjuvant chemotherapy involves the use of antineoplastic drugs when surgery or radiation therapy has eradicated the primary tumor but historical experience with similar patients indicates a high risk of relapse due to micrometastases. Adjuvant chemotherapy should employ drugs that are known to be effective in the treatment of advanced stages of the particular tumor being treated. Adjuvant chemotherapy has played a major role in the cure of several types of childhood cancers as well as breast cancer, colorectal cancer, and osteosarcoma in adults. 

Andre T, de Gramont A, Study Group of Clinical Research in Radiotherapies Oncology, Oncology Multi-diciplinary Research Group. An overview of adjuvant systemic chemotherapy for colon cancer. Clin Colorectal Cancer. 2004 4(suppl 1) S22—S28. 

Every Monday in your oncology outpatient department, you run a pharmacist/ nurse-led oral capecitabine clinic, where patients are referred to you by oncologists for pretreatment counselling, drug history-taking and supplementary chemotherapy prescribing (under set clinical management plans) for the adjuvant treatment of colon cancer or treatment of metastatic colorectal cancer. 

Leen, E., Goldberg, J.A., Angerson, W.J., McArdle, C.S. Potential role of Doppler perfusion index in selection of patients with colorectal cancer for adjuvant chemotherapy. Lancet 2000 355 34-37... 

Kerr DJ. A United Kingdom Coordinating Committee on Cancer Research study of adjuvant chemotherapy for colorectal cancer preliminary results Semin Oncol 2001 28 (1 Suppl l) 31-4. 

Vaughn DJ, Haller DG. The role of adjuvant chemotherapy in the treatment of colorectal cancer. Hematol Oncol Clin North Am 1997 11(4) 699-719. 

Hodi FS, Catalano P, Macdonald JS, et al. Age as a factor influencing the toxicity of adjuvant chemotherapy for colorectal cancer. In 2nd International conference on gastrointestinal oncology. Cologne, Germany 1994. 

Microbubbles can also be used as tracers in the liver the time taken for them to cross into the hepatic veins (normally 30 s or more, owing to the slow flow in the liver sinusoids) is shortened when there is arteriovenous shunting, as occurs in metas-tases and cirrhosis (Albrecht et al. 1999 Blomley 1997). This simple test seems to be able to detect occult metastases, for example in colorectal cancer, and might prove useful in selecting patients for adjuvant chemotherapy. 

Scaife CL, Curley SA, Izzo F, et al (2003) Feasibility of adjuvant hepatic arterial infusion of chemotherapy after radiofrequency ablation with or without resection in patients with hepatic metastases from colorectal cancer. Ann Surg Oncol 10 348-354... 

W. B. Forman, The role of chemotherapy and adjuvant therapy in the management of colorectal cancer. Cancer, 1994, 74, 2151-2153. 

Arsenic exposure contributes to cancer risk and has been associated with decreased ERCCl expression in isolated lymphocytes at the mRNA and protein levels (51). Along the same lines, increased expression of defense genes, like ERCCl, has been observed in premalignant lesions, such as colorectal adenomas (52). In early-stage NSCLC, high ERCC 1 expression has been observed in almost half of the patients, indicating both a lower risk of relapse and a lower probability of benefit from adjuvant cisplatin-based chemotherapy. 

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