Kim NK et al. (2006) Oncologic outcomes after neoadjuvant chemoradiation followed by curative resection with tumor-specific mesorectal excision for fixed locally advanced rectal cancer: impact of postirradiated pathologic downstaging on local recurrence and survival. Ann Surg 244: 1024–1030

Surgery for rectal cancer is associated with a high rate of recurrence (50–70%) when the cancer is fixed on presentation. Neoadjuvant chemoradiation can reduce the tumor volume and pathologic tumor stage of locally advanced rectal cancer, increasing the likelihood of curative surgical resectability and improving long-term oncologic outcomes. A retrospective analysis has shown that the pathologic tumor stage after curative resection and neoadjuvant chemoradiotherapy correlates highly with outcome in locally advanced and fixed rectal cancer.

Data were assessed from 114 patients with advanced (stage T3 or T4, N-positive) rectal cancer who had undergone chemoradiation (5,040 cGy in 25 fractions over 5 weeks, with intravenous 5-fluorouracil and leucovorin during weeks 1 and 5), followed 4–6 weeks later by tumor-specific mesorectal excision. Tumors were staged using the pathological tumor–node–metastasis (TNM) system.

Recurrence and 5-year survival rates both correlated positively with pathologic stage. While patients in pathologic complete remission had a highly favorable prognosis, with 100% (10/10) still alive at 5 years, stage II and III patients had overall survival rates of 56.8% and 42.3%, respectively, and disease-free survival rates of 49.7% and 33.6%. In multivariate analysis, pathologic nodal stage and the operative method both independently affected survival, and the authors propose that pathologic nodal status following irradiation has the strongest effect on oncologic outcomes. Longer follow-up is, however, required before a definitive relationship between pathologic complete remission and a favorable prognosis can be inferred.