In the Netherlands, Maas and colleagues at Maastricht University described 192 patients treated with combined modality therapy between 2004 and 2010, of whom 21 (11%) had a complete clinical response.4 A complete clinical response was defined as no residual tumor at endoscopy or only a small residual erythematous ulcer or scar; negative biopsies from the scar, ulcer, or former tumor location; no palpable tumor after initial palpability; and no suspicious lymph nodes on magnetic resonance imaging.

Adjuvant chemotherapy was given to those with positive nodal status at primary staging. Twenty (10%) patients were found to have a pathologic complete response and functioned as the comparison group. In the nonoperative management group, 2-year disease-free and overall survival were 100% and 89%, respectively, and not different from the resection group. Compared with the Habr-Gama and colleagues series, this report demonstrated a lower rate of complete clinical response, a similar rate of pathologic complete response, and a lower rate of local recurrence. These differences may be related to patient selection and length of follow-up. Again, these data demonstrate comparable overall and disease-free survival rates between patients selected for nonoperative management and those who had resection with a pathologic complete response as well as the success of salvage surgery.

The experience from Memorial Sloan Kettering Cancer Center was first published in 2012 and updated at the American Society of Clinical Oncology’s Gastrointestinal Cancers Symposium in 2015.5,6 Seventy-three patients were treated nonoperatively between 2006 and 2010. Local tumor regrowth was noted in 19 (26%) patients, who were treated with subsequent resection. Similar to the experience from Sao Paulo and Maastricht, 70% of tumor regrowth occurred within 13 months of completing chemoradiation. The cohort treated with nonoperative management was compared with 72 patients who underwent resection with a pathologic complete response. In this retrospective study, disease-free and overall survival were similar, indicating that tumor regrowth could be salvaged and did not appear to lead to distant metastases.

You can find more in Procedures for Rectal Cancer in Scientific AmericanTM Surgery.

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  1. Habr-Gama A, Perez RO, Nadalin W, et al. Operative versus nonoperative treatment for stage 0 distal rectal cancer following chemoradiation therapy: long-term results. Ann Surg 2004;240:711–7; discussion 717–8.
  2. Habr-Gama A, Perez RO, Proscurshim I, et al. Patterns of failure and survival for nonoperative treatment of stage c0 distal rectal cancer following neoadjuvant chemoradiation therapy. J Gastrointest Surg 2006;10:1319–28; discussion 1328–1319.
  3. Habr-Gama A, Gama-Rodrigues J, São Julião GP, et al. Local recurrence after complete clinical response and watch and wait in rectal cancer after neoadjuvant chemoradiation: impact of salvage therapy on local disease control. Int J Radiat Oncol Biol Phys 2014;88:822–8.
  4. Maas M, Beets-Tan R, Lambregts DM, et al. Wait-and-see policy for clinical complete responders after chemoradiation for rectal cancer. J Clin Oncol 2011;29:4633–40.
  5. Smith JJ, Chow OS, Eaton A, et al. Organ preservation in patients with rectal cancer with clinical complete response after neoadjuvant therapy [abstract]. J Clin Oncol (Meeting Abstracts) 2015;33 (3 Suppl):509.
  6. Helwick C. Observation appropriate for some patients with rectal cancer following neoadjuvant therapy. The ASCO Post. Available at:,-2015/observation-appropriate-for-some-patients-with-rectal-cancer-following-neoadjuvant-therapy.aspx (accessed May 12, 2015).