Rectal cancer therapy

There is currently no definitive role for adjuvant radiation in colon cancer. However, patients who receive surgery for rectal cancer receive radiation therapy to reduce local tumor recurrence. Adjuvant radiation plus chemotherapy is considered standard treatment for patients with stage II or III rectal cancer after the surgical procedure is complete.17 Preoperative radiation may be used to reduce the initial size of rectal cancers in order to make the surgical procedure easier. 

Another unique aspect of rectal cancer is the use of neoadjuvant therapy. Preoperative radiation with or without chemotherapy is given to downstage the tumor prior to surgical resection to improve sphincter preservation by making the surgical procedure easier to perform. The issue of preoperative versus postoperative radiation is a subject of debate and investigation in the United States and will require further data to determine the superiority of one method over the other. 

A phase I study of Xeloda in combination with XRT in rectal cancer is in the adjuvant, neoadjuvant, and palliative settings (71-73). The DLT of the combination is hand-foot syndrome and mild to moderate leukopenia, diarrhea, and local skin reaction (71-73). The recommended dose for phase 2 studies is Xeloda 825 mg/m2 twice daily without interruption in combination with standard dose of radiation. Promising activity has been demonstrated in neoadjuvant therapy with six objective responses in seven evaluable patients including one pathological confirmed CR. 

Dukes B2 and C rectal cancer GITSG No adjuvant therapy Radiation (40 14 Gy + 5-FU + semustine 35%b 55%b... 

Hoff PM, Janjan N, Saad Ed, et al. Phase I study of preoperative oral uracil and tegafurplus leucovorin and radiation therapy in rectal cancer. J Clin Oncol 2000 18 3529-3534. 

O Connell MJ, Martenson JA, Wieand HS, et al. Improving adjuvant therapy for rectal cancer by combining protracted-infusion fluoro uracil with radiation therapy after curative surgery. N Engl J Med 1994 331 502-507. 

Radiation Therapy Oncology Group RTOG R-0012 Randomized Phase II Trial of Preoperative Combined Modality Chemoradiation for Distal Rectal Cancer... 

Mitchell EP. Irinotecan in preoperative combined-modality therapy for locally advanced rectal cancer. Oncology (Huntingt) 2000 14(12 Suppl 14) 56-59. 

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. 

Table 4 Accepted Adjuvant Therapy Regimens for High-Risk Rectal Cancer Patients ...

Tepper JE, Cohen AM, Wood WC, et al. Postoperative radiation therapy of rectal cancer. Int J Radiat Oncol Biol Phys 1987 13 5-10. 

Fisher B, Wolmark N, Rockette H, et al. Postoperative adjuvant chemotherapy or radiation therapy for rectal cancer results from NSABP protocol R-01. J Natl Cancer Inst 1988 80 21-29. 

NIH Consensus Conference. Adjuvant therapy for patients with colon and rectal cancer. J Am Med Assoc 1990 264 1444-1450. 

Tepper JE, O Connell MJ, Petroni GR, et al. Adjuvant postoperative fluorouracil-modulated chemotherapy combined with pelvic radiation therapy for rectal cancer initial results of Intergroup 0114. J Clin Oncol 1997 15(5) 2030-2039. 

Haller DG. Defining the optimal therapy for rectal cancer [letter]. JNatl Cancer Inst 2000 92(5) 361-362. 

Minsky BD, Cohen AM, Enker WE, et al. Preoperative 5-FU, low-dose leucovorin, and radiation therapy for locally advanced and unresectable rectal cancer. Ini J Radiat Oncol Biol Phys 1997 37(2) 289-295. 

Wagman R, Minsky BD, Cohen AM, et al. Sphincter preservation in rectal cancer with preoperative radiation therapy and coloanal anastomosis long term follow-up. Int JRadiat Oncol Biol Phys 1998 42 51-57. 

Francois Y, Nemoz CJ, Baulieux J, et al. Influence of the interval between preoperative radiation therapy and surgery on downstaging and on the rate of sphincter-sparing surgery for rectal cancer the Lyon R90-01 randomized trial. J Clin Oncol 1999 17(8) 2396-2402. 

Ota DM, Skibber J, Rich TA. M.D. Anderson Cancer Center experience with local excision and multimodality therapy for rectal cancer. Surg Oncol Clin North Am 1992 1 147-152. 

MeLeod HL, Tan B, Malyapa R et al. Genotype-guided neoadjuvant therapy for rectal cancer. Proc Am Soc Clin Oncol 2005 23 197. 

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