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Rectal Cancer Treatment (PDQ®)

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Treatment Option Overview for Rectal Cancer

The management of rectal cancer varies somewhat from that of colon cancer because of the increased risk of local recurrence and a poorer overall prognosis. Differences include surgical technique, the use of radiation therapy, and the method of chemotherapy administration. In addition to determining the intent of rectal cancer surgery (i.e., curative or palliative), it is important to consider therapeutic issues related to the maintenance or restoration of normal anal sphincter, genitourinary function, and sexual function.[1,2]

The approach to the management of rectal cancer is multimodal and involves a multidisciplinary team of cancer specialists with expertise in gastroenterology, medical oncology, surgical oncology, radiation oncology, and radiology.

Table 6. Standard Treatment Options for Stages 0–III Rectal Cancer
Stage (TNM Staging Criteria) Standard Treatment Options
Stage 0 Rectal CancerPolypectomy or surgery
Stage I Rectal CancerSurgery with or without chemoradiation therapy
Stages II and III Rectal CancerSurgery
Preoperative chemoradiation therapy
Short-course preoperative radiation therapy
Postoperative chemoradiation therapy
Table 7. Treatment Options for Stage IV and Recurrent Rectal Cancer
Stage (TNM Staging Criteria) Treatment Options
Stage IV and Recurrent Rectal CancerSurgery with or without chemotherapy or radiation therapy
First-line chemotherapy and targeted therapy
Second-line chemotherapy
Palliative therapy
Liver MetastasesSurgery
Neoadjuvant chemotherapy
Local ablation
Adjuvant chemotherapy
Intra-arterial chemotherapy

Primary Surgical Therapy

The primary treatment for patients with rectal cancer is surgical resection of the primary tumor. The surgical approach to treatment varies according to the following:

  • Tumor location.
  • Stage of disease.
  • Presence or absence of high-risk features (i.e., positive margins, lymphovascular invasion, perineural invasion, and poorly differentiated histology).

Types of surgical resection include the following:[1-3]

  • Polypectomy for select T1 cancers.
  • Transanal local excision and transanal endoscopic microsurgery for select clinically staged T1/T2 N0 rectal cancers.
  • Total mesorectal excision with autonomic nerve preservation techniques via low-anterior resection.
  • Total mesorectal excision via abdominoperineal resection for patients who are not candidates for sphincter-preservation, leaving patients with a permanent end-colostomy.

Polypectomy alone may be used in certain instances (T1) in which polyps with invasive cancer can be completely resected with clear margins and have favorable histologic features.[4,5]

Local excision of clinical T1 tumors is an acceptable surgical technique for appropriately selected patients. For all other tumors, a mesorectal excision is the treatment of choice. Very select patients with T2 tumors may be candidates for local excision. Local failure rates in the range of 4% to 8% after rectal resection with appropriate mesorectal excision (total mesorectal excision for low/middle rectal tumors and mesorectal excision at least 5 cm below the tumor for high rectal tumors) have been reported.[6-10]

For patients with advanced cancers of the mid- to upper rectum, low-anterior resection followed by the creation of a colorectal anastomosis may be the treatment of choice. For locally advanced rectal cancers for which radical resection is indicated, however, total mesorectal excision with autonomic nerve preservation techniques via low-anterior resection is preferable to abdominoperineal resection.[1,2]

The low incidence of local relapse after meticulous mesorectal excision has led some investigators to question the routine use of adjuvant radiation therapy. Because of an increased tendency for first failure in locoregional sites only, the impact of perioperative radiation therapy is greater in rectal cancer than in colon cancer.[11]

Chemoradiation Therapy

Preoperative chemoradiation therapy

Neoadjuvant therapy for rectal cancer, using preoperative chemoradiation therapy, is the preferred treatment option for patients with stages II and III disease. However, postoperative chemoradiation therapy for patients with stage II or III rectal cancer remains an acceptable option.[12][Level of evidence: 1iA]

Preoperative chemoradiation therapy has become the standard of care for patients with clinically staged T3–T4 or node-positive disease (stages II/III), based on the results of several studies:

Multiple phase II and III studies examined the benefits of preoperative chemoradiation therapy, which include the following:[12]

  • Tumor regression and downstaging of the tumor.
  • Improved tumor resectability.
  • Higher rate of local control.
  • Improved toxicity profile of chemoradiation therapy.
  • Higher rate of sphincter preservation.

Complete pathologic response rates of 10% to 25% may be achieved with preoperative chemoradiation therapy.[15-22] However, preoperative radiation therapy is associated with increased complications compared with surgery alone; some patients with cancers at a lower risk of local recurrence might be adequately treated with surgery and adjuvant chemotherapy.[23-26]

(Refer to the Preoperative chemoradiation therapy section in the Stages II and III Rectal Cancer section of this summary for more information about these studies.)

Postoperative chemoradiation therapy

Preoperative chemoradiation therapy is the current standard of care for stages II and III rectal cancer. However, before 1990, the following studies noted an increase in both disease-free survival (DFS) and overall survival (OS) with the use of postoperative combined-modality therapy:

  1. The Gastrointestinal Tumor Study Group trial (GITSG-7175).
  2. The Mayo/North Central Cancer Treatment Group trial (NCCTG-794751).
  3. The National Surgical Adjuvant Breast and Bowel Project trial (NSABP-R-01).

Subsequent studies have attempted to increase the survival benefit by improving radiation sensitization and by identifying the optimal chemotherapeutic agents and delivery systems.

Fluorouracil (5-FU): The following studies examined optimal delivery methods for adjuvant 5-FU:

  1. Intergroup protocol 86-47-51 trial (MAYO-864751).[27][Level of evidence: 1iiA]
  2. Intergroup 0114 trial (INT-0114 [CLB-9081]).[25][Level of evidence: 1iiA]
  3. Intergroup 0144.[28]

(Refer to the Stages II and III Rectal Cancer section of this summary for detailed information about these study results.)

Acceptable postoperative chemoradiation therapy for patients with stage II or III rectal cancer not enrolled in clinical trials includes continuous-infusion 5-FU during 45 Gy to 55 Gy pelvic radiation and four cycles of adjuvant maintenance chemotherapy with bolus 5-FU with or without modulation with leucovorin (LV).

Findings from the NSABP-R-01 trial compared surgery alone with surgery followed by chemotherapy or radiation therapy.[29] Subsequently, the NSABP-R-02 study, addressed whether adding postoperative radiation therapy to chemotherapy would enhance the survival advantage reported in R-01.[30][Level of evidence: 1iiA]

In the NSABP-R-02 study, the addition of radiation therapy significantly reduced local recurrence at 5 years (8% for chemotherapy and radiation vs. 13% for chemotherapy alone, P = .02) but failed to demonstrate a significant survival benefit. Radiation therapy appeared to improve survival among patients younger than 60 years and among patients who underwent abdominoperineal resection.

While this trial has initiated discussion in the oncologic community about the proper role of postoperative radiation therapy, omission of radiation therapy seems premature because of the serious complications of locoregional recurrence.

Chemotherapy regimens

Table 8 describes the chemotherapy regimens used to treat rectal cancer.

Table 8. Drug Combinations Used to Treat Rectal Cancer
Regimen NameDrug CombinationDose
5-FU = fluorouracil; IV = intravenous; LV = leucovorin.
Arbeitsgemeinschaft Internistische Onkologie (AIO) or German AIOFolic acid, 5-FU, and irinotecanIrinotecan (100 mg/m2) and LV (500 mg/m2) administered as 2-hour infusions on day 1, followed by 5-FU (2,000 mg/m2) IV bolus administered via ambulatory pump weekly over 24 hours, 4 times a year (52 weeks).
CAPOXCapecitabine and oxaliplatinCapecitabine (1,000 mg/m2) twice daily on days 1 through 14, plus oxaliplatin (70 mg/m2) on days 1 and 8 every 3 weeks.
DouillardFolic acid, 5-FU, and irinotecanIrinotecan (180 mg/m2) administered as a 2-hour infusion on day 1, LV (200 mg/m2) administered as a 2-hour infusion on days 1 and 2, followed by a loading dose of 5-FU (400 mg/m2) IV bolus, then 5-FU (600 mg/m2) administered via ambulatory pump over 22 hours every 2 weeks on days 1 and 2.
FOLFIRILV, 5-FU, and irinotecanIrinotecan (180 mg/m2) and LV (400 mg/m2) administered as 2-hour infusions on day 1, followed by a loading dose of 5-FU (400 mg/m2) IV bolus administered on day 1, then 5-FU (2,400–3,000 mg/m2) administered via ambulatory pump over 46 hours every 2 weeks.
FOLFOX4Oxaliplatin, LV, and 5-FUOxaliplatin (85 mg/m2) administered as a 2-hour infusion on day 1, LV (200 mg/m2) administered as a 2-hour infusion on days 1 and 2, followed by a loading dose of 5-FU (400 mg/m2) IV bolus, then 5-FU (600 mg/m2) administered via ambulatory pump over 22 hours every 2 weeks on days 1 and 2.
FOLFOX6Oxaliplatin, LV, and 5-FUOxaliplatin (85–100 mg/m2) and LV (400 mg/m2) administered as 2-hour infusions on day 1, followed by a loading dose of 5-FU (400 mg/m2) IV bolus on day 1, then 5-FU (2,400–3,000 mg/m2) administered via ambulatory pump over 46 hours every 2 weeks.
FOLFOXIRIIrinotecan, oxaliplatin, LV, 5-FUIrinotecan (165 mg/m2) administered as a 60-minute infusion, then concomitant infusion of oxaliplatin (85 mg/m2) and LV (200 mg/m2) over 120 minutes, followed by 5-FU (3,200 mg/m2) administered as a 48-hour continuous infusion.
FUFOX5-FU, LV, and oxaliplatinOxaliplatin (50 mg/m2) plus LV (500 mg/m2) plus 5-FU (2,000 mg/m2) administered as a 22-hour continuous infusion on days 1, 8, 22, and 29 every 36 days.
FUOX5-FU plus oxaliplatin5-FU (2,250 mg/m2) administered as a continuous infusion over 48 hours on days 1, 8, 15, 22, 29, and 36 plus oxaliplatin (85 mg/m2) on days 1, 15, and 29 every 6 weeks.
IFL (or Saltz)Irinotecan, 5-FU, and LVIrinotecan (125 mg/m2) plus 5-FU (500 mg/m2) IV bolus and LV (20 mg/m2) IV bolus administered weekly for 4 out of 6 weeks.
XELOXCapecitabine plus oxaliplatinOral capecitabine (1,000 mg/m2) administered twice daily for 14 days plus oxaliplatin (130 mg/m2) on day 1 every 3 weeks.

Treatment toxicity

The acute side effects of pelvic radiation therapy for rectal cancer are mainly the result of gastrointestinal toxicity, are self-limiting, and usually resolve within 4 to 6 weeks of completing treatment.

Of greater concern is the potential for late morbidity after rectal cancer treatment. Patients who undergo aggressive surgical procedures for rectal cancer can have chronic symptoms, particularly if there is impairment of the anal sphincter.[31] Patients treated with radiation therapy appear to have increased chronic bowel dysfunction, anorectal sphincter dysfunction (if the sphincter was surgically preserved), and sexual dysfunction than do patients who undergo surgical resection alone.[24,32-37]

An analysis of patients treated with postoperative chemotherapy and radiation therapy suggests that these patients may have more chronic bowel dysfunction than do patients who undergo surgical resection alone.[38] A Cochrane review highlights the risks of increased surgical morbidity as well as late rectal and sexual function in association with radiation therapy.[31]

Improved radiation therapy planning and techniques may minimize these acute and late treatment-related complications. These techniques include the following:[39-43]

  • The use of high-energy radiation machines.
  • The use of multiple pelvic radiation fields.
  • Prone patient positioning.
  • Customized patient molds (belly boards) to exclude as much small bowel as possible from the radiation fields and immobilize patients during treatment.
  • Bladder distention during radiation therapy to exclude as much small bowel as possible from the radiation fields.
  • Visualization of the small bowel through oral contrast during treatment planning so that when possible, the small bowel can be excluded from the radiation field.
  • The use of 3-dimensional or other advanced radiation planning techniques.

In Europe, it is common to deliver preoperative radiation therapy alone in one week (5 Gy  × five daily treatments) followed by surgery one week later, rather than the long-course chemoradiation approach used in the United States. One reason for this difference is the concern in the United States for heightened late effects when high radiation doses per fraction are given.

A Polish study randomly assigned 316 patients to preoperative long-course chemoradiation therapy (50.4 Gy in 28 daily fractions with 5-FU and LV) or short-course preoperative radiation therapy (25 Gy in five fractions).[37] Although the primary endpoint was sphincter preservation, late toxicity was not statistically significantly different between the two treatment approaches (7% long course vs. 10% short course). Of note, data on anal sphincter and sexual function were not reported, and toxicity was physician determined, not patient reported.

Ongoing clinical trials comparing preoperative and postoperative adjuvant chemoradiation therapy should further clarify the impact of either approach on bowel function and other important quality-of-life issues (e.g., sphincter preservation) in addition to the more conventional endpoints of DFS and OS.


  1. Balch GC, De Meo A, Guillem JG: Modern management of rectal cancer: a 2006 update. World J Gastroenterol 12 (20): 3186-95, 2006. [PUBMED Abstract]
  2. Baxter NN, Garcia-Aguilar J: Organ preservation for rectal cancer. J Clin Oncol 25 (8): 1014-20, 2007. [PUBMED Abstract]
  3. Guillem JG, Cohen AM: Current issues in colorectal cancer surgery. Semin Oncol 26 (5): 505-13, 1999. [PUBMED Abstract]
  4. Cooper HS, Deppisch LM, Gourley WK, et al.: Endoscopically removed malignant colorectal polyps: clinicopathologic correlations. Gastroenterology 108 (6): 1657-65, 1995. [PUBMED Abstract]
  5. Seitz U, Bohnacker S, Seewald S, et al.: Is endoscopic polypectomy an adequate therapy for malignant colorectal adenomas? Presentation of 114 patients and review of the literature. Dis Colon Rectum 47 (11): 1789-96; discussion 1796-7, 2004. [PUBMED Abstract]
  6. MacFarlane JK, Ryall RD, Heald RJ: Mesorectal excision for rectal cancer. Lancet 341 (8843): 457-60, 1993. [PUBMED Abstract]
  7. Enker WE, Thaler HT, Cranor ML, et al.: Total mesorectal excision in the operative treatment of carcinoma of the rectum. J Am Coll Surg 181 (4): 335-46, 1995. [PUBMED Abstract]
  8. Zaheer S, Pemberton JH, Farouk R, et al.: Surgical treatment of adenocarcinoma of the rectum. Ann Surg 227 (6): 800-11, 1998. [PUBMED Abstract]
  9. Heald RJ, Smedh RK, Kald A, et al.: Abdominoperineal excision of the rectum--an endangered operation. Norman Nigro Lectureship. Dis Colon Rectum 40 (7): 747-51, 1997. [PUBMED Abstract]
  10. Lopez-Kostner F, Lavery IC, Hool GR, et al.: Total mesorectal excision is not necessary for cancers of the upper rectum. Surgery 124 (4): 612-7; discussion 617-8, 1998. [PUBMED Abstract]
  11. Gunderson LL, Sosin H: Areas of failure found at reoperation (second or symptomatic look) following "curative surgery" for adenocarcinoma of the rectum. Clinicopathologic correlation and implications for adjuvant therapy. Cancer 34 (4): 1278-92, 1974. [PUBMED Abstract]
  12. Sauer R, Becker H, Hohenberger W, et al.: Preoperative versus postoperative chemoradiotherapy for rectal cancer. N Engl J Med 351 (17): 1731-40, 2004. [PUBMED Abstract]
  13. Sauer R, Liersch T, Merkel S, et al.: Preoperative versus postoperative chemoradiotherapy for locally advanced rectal cancer: results of the German CAO/ARO/AIO-94 randomized phase III trial after a median follow-up of 11 years. J Clin Oncol 30 (16): 1926-33, 2012. [PUBMED Abstract]
  14. Roh MS, Colangelo LH, O'Connell MJ, et al.: Preoperative multimodality therapy improves disease-free survival in patients with carcinoma of the rectum: NSABP R-03. J Clin Oncol 27 (31): 5124-30, 2009. [PUBMED Abstract]
  15. Janjan NA, Khoo VS, Abbruzzese J, et al.: Tumor downstaging and sphincter preservation with preoperative chemoradiation in locally advanced rectal cancer: the M. D. Anderson Cancer Center experience. Int J Radiat Oncol Biol Phys 44 (5): 1027-38, 1999. [PUBMED Abstract]
  16. Crane CH, Skibber JM, Birnbaum EH, et al.: The addition of continuous infusion 5-FU to preoperative radiation therapy increases tumor response, leading to increased sphincter preservation in locally advanced rectal cancer. Int J Radiat Oncol Biol Phys 57 (1): 84-9, 2003. [PUBMED Abstract]
  17. Grann A, Minsky BD, Cohen AM, et al.: Preliminary results of preoperative 5-fluorouracil, low-dose leucovorin, and concurrent radiation therapy for clinically resectable T3 rectal cancer. Dis Colon Rectum 40 (5): 515-22, 1997. [PUBMED Abstract]
  18. Rich TA, Skibber JM, Ajani JA, et al.: Preoperative infusional chemoradiation therapy for stage T3 rectal cancer. Int J Radiat Oncol Biol Phys 32 (4): 1025-9, 1995. [PUBMED Abstract]
  19. Chari RS, Tyler DS, Anscher MS, et al.: Preoperative radiation and chemotherapy in the treatment of adenocarcinoma of the rectum. Ann Surg 221 (6): 778-86; discussion 786-7, 1995. [PUBMED Abstract]
  20. Hyams DM, Mamounas EP, Petrelli N, et al.: A clinical trial to evaluate the worth of preoperative multimodality therapy in patients with operable carcinoma of the rectum: a progress report of National Surgical Breast and Bowel Project Protocol R-03. Dis Colon Rectum 40 (2): 131-9, 1997. [PUBMED Abstract]
  21. Bosset JF, Magnin V, Maingon P, et al.: Preoperative radiochemotherapy in rectal cancer: long-term results of a phase II trial. Int J Radiat Oncol Biol Phys 46 (2): 323-7, 2000. [PUBMED Abstract]
  22. Hiotis SP, Weber SM, Cohen AM, et al.: Assessing the predictive value of clinical complete response to neoadjuvant therapy for rectal cancer: an analysis of 488 patients. J Am Coll Surg 194 (2): 131-5; discussion 135-6, 2002. [PUBMED Abstract]
  23. Lai LL, Fuller CD, Kachnic LA, et al.: Can pelvic radiotherapy be omitted in select patients with rectal cancer? Semin Oncol 33 (6 Suppl 11): S70-4, 2006. [PUBMED Abstract]
  24. Peeters KC, van de Velde CJ, Leer JW, et al.: Late side effects of short-course preoperative radiotherapy combined with total mesorectal excision for rectal cancer: increased bowel dysfunction in irradiated patients--a Dutch colorectal cancer group study. J Clin Oncol 23 (25): 6199-206, 2005. [PUBMED Abstract]
  25. Tepper JE, O'Connell M, Niedzwiecki D, et al.: Adjuvant therapy in rectal cancer: analysis of stage, sex, and local control--final report of intergroup 0114. J Clin Oncol 20 (7): 1744-50, 2002. [PUBMED Abstract]
  26. Gunderson LL, Sargent DJ, Tepper JE, et al.: Impact of T and N stage and treatment on survival and relapse in adjuvant rectal cancer: a pooled analysis. J Clin Oncol 22 (10): 1785-96, 2004. [PUBMED Abstract]
  27. O'Connell MJ, Martenson JA, Wieand HS, et al.: Improving adjuvant therapy for rectal cancer by combining protracted-infusion fluorouracil with radiation therapy after curative surgery. N Engl J Med 331 (8): 502-7, 1994. [PUBMED Abstract]
  28. Smalley SR, Benedetti JK, Williamson SK, et al.: Phase III trial of fluorouracil-based chemotherapy regimens plus radiotherapy in postoperative adjuvant rectal cancer: GI INT 0144. J Clin Oncol 24 (22): 3542-7, 2006. [PUBMED Abstract]
  29. 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 80 (1): 21-9, 1988. [PUBMED Abstract]
  30. Wolmark N, Wieand HS, Hyams DM, et al.: Randomized trial of postoperative adjuvant chemotherapy with or without radiotherapy for carcinoma of the rectum: National Surgical Adjuvant Breast and Bowel Project Protocol R-02. J Natl Cancer Inst 92 (5): 388-96, 2000. [PUBMED Abstract]
  31. Wong RK, Tandan V, De Silva S, et al.: Pre-operative radiotherapy and curative surgery for the management of localized rectal carcinoma. Cochrane Database Syst Rev (2): CD002102, 2007. [PUBMED Abstract]
  32. Randomised trial of surgery alone versus surgery followed by radiotherapy for mobile cancer of the rectum. Medical Research Council Rectal Cancer Working Party. Lancet 348 (9042): 1610-4, 1996. [PUBMED Abstract]
  33. Initial report from a Swedish multicentre study examining the role of preoperative irradiation in the treatment of patients with resectable rectal carcinoma. Swedish Rectal Cancer Trial. Br J Surg 80 (10): 1333-6, 1993. [PUBMED Abstract]
  34. Dahlberg M, Glimelius B, Graf W, et al.: Preoperative irradiation affects functional results after surgery for rectal cancer: results from a randomized study. Dis Colon Rectum 41 (5): 543-9; discussion 549-51, 1998. [PUBMED Abstract]
  35. Birgisson H, Påhlman L, Gunnarsson U, et al.: Adverse effects of preoperative radiation therapy for rectal cancer: long-term follow-up of the Swedish Rectal Cancer Trial. J Clin Oncol 23 (34): 8697-705, 2005. [PUBMED Abstract]
  36. Marijnen CA, van de Velde CJ, Putter H, et al.: Impact of short-term preoperative radiotherapy on health-related quality of life and sexual functioning in primary rectal cancer: report of a multicenter randomized trial. J Clin Oncol 23 (9): 1847-58, 2005. [PUBMED Abstract]
  37. Bujko K, Nowacki MP, Nasierowska-Guttmejer A, et al.: Long-term results of a randomized trial comparing preoperative short-course radiotherapy with preoperative conventionally fractionated chemoradiation for rectal cancer. Br J Surg 93 (10): 1215-23, 2006. [PUBMED Abstract]
  38. Kollmorgen CF, Meagher AP, Wolff BG, et al.: The long-term effect of adjuvant postoperative chemoradiotherapy for rectal carcinoma on bowel function. Ann Surg 220 (5): 676-82, 1994. [PUBMED Abstract]
  39. Martling A, Holm T, Johansson H, et al.: The Stockholm II trial on preoperative radiotherapy in rectal carcinoma: long-term follow-up of a population-based study. Cancer 92 (4): 896-902, 2001. [PUBMED Abstract]
  40. Dahlberg M, Glimelius B, Påhlman L: Improved survival and reduction in local failure rates after preoperative radiotherapy: evidence for the generalizability of the results of Swedish Rectal Cancer Trial. Ann Surg 229 (4): 493-7, 1999. [PUBMED Abstract]
  41. Guerrero Urbano MT, Henrys AJ, Adams EJ, et al.: Intensity-modulated radiotherapy in patients with locally advanced rectal cancer reduces volume of bowel treated to high dose levels. Int J Radiat Oncol Biol Phys 65 (3): 907-16, 2006. [PUBMED Abstract]
  42. Koelbl O, Richter S, Flentje M: Influence of patient positioning on dose-volume histogram and normal tissue complication probability for small bowel and bladder in patients receiving pelvic irradiation: a prospective study using a 3D planning system and a radiobiological model. Int J Radiat Oncol Biol Phys 45 (5): 1193-8, 1999. [PUBMED Abstract]
  43. Gunderson LL, Russell AH, Llewellyn HJ, et al.: Treatment planning for colorectal cancer: radiation and surgical techniques and value of small-bowel films. Int J Radiat Oncol Biol Phys 11 (7): 1379-93, 1985. [PUBMED Abstract]
  • Updated: January 26, 2015