Management and Outcomes of Pathologic Upstaging of Clinical Stage I Rectal Cancers: An Exploratory Analysis

BACKGROUND: Preoperative staging of clinical stage I rectal cancer can fail to diagnose T3 or nodal disease. Adjuvant treatment of these upstaged patients remains controversial.OBJECTIVE: The objective was to identify predictors of clinical stage I rectal cancer upstaging and quantify rates of local and systemic recurrence. DESIGN: This was a retrospective cohort study.SETTINGS: The study was conducted using data from the United States Rectal Cancer Consortium, a registry of 1881 rectal cancer resections performed at 6 academic medical centers.PATIENTS: There were a total of 94 clinical stage I rectal cancer patients who underwent proctectomy without preoperative therapy.MAIN OUTCOME MEASURES: The primary measures were incidence of pathologic upstaging, recurrence (local and systemic), and overall survival.RESULTS: Among 94 clinical stage I patients who underwent proctectomy without preoperative therapy, 23 (24.5%) were upstaged by surgical pathology. There were 6 pT3N0 patients, 8 pT1-2N+ patients, and 9 pT3N+ patients. There were no significant differences in demographic or clinical characteristics between upstaged and nonupstaged patients. Of the 6 patients who were upstaged to T3N0 disease, none received adjuvant therapy and none developed recurrence. Of the 17 patients who were upstaged to N+ disease, 14 (82%) received adjuvant chemotherapy and 6 (35%) received adjuvant chemoradiation. None developed a local recurrence, but 4 (24%) developed systemic recurrence, and 2 (12%) died of disease over a mean of 36 months of follow-up. Among the 9 pT3N+ patients, the systemic recurrence rate was 33%, despite 8 of 9 patients receiving adjuvant fluorouracil, leucovorin, and oxaliplatin.LIMITATIONS: Small sample size hinders the ability to draw significant conclusions. CONCLUSIONS: One in 4 patients with stage I rectal cancer had unrecognized T3 or nodal disease found on operative pathology. Occult nodal disease was associated with worse outcomes, despite receiving adjuvant therapy. Systemic recurrence was more common than local recurrence.