Sphincter preservation rates after radical resection for rectal cancer in the United States veteran population: opportunity for improvement in early disease.

BACKGROUND

Sphincter preservation (SP) is an important goal of rectal cancer surgery. We hypothesized that SP rates among veteran patients have increased and are comparable to national rates, and that a subset of patients with early disease still undergo non-SP procedures.

METHODS

Patients with nonmetastatic primary rectal adenocarcinoma who underwent curative-intent rectal resection were identified from the Veterans Affairs Central Cancer Registry (VACCR) database (1995-2010). SP trends over time were described and compared to the Surveillance, Epidemiology, and End-Results (SEER) population. Subset analysis was performed in patients with nonirradiated, pathologic stage 0-I rectal cancers, a population that may qualify for novel SP strategies.

RESULTS

Of 5,145 study patients, 3,509 (68 %) underwent SP surgery. The VACCR SP rate increased from 59.9 % in 1995-1999 to 79.3 % in 2005-2010, when it exceeded that of SEER (76.9 %, p = 0.023). On multivariate analysis, recent time period was independently associated with higher likelihood of SP (odds ratio [OR] 2.64, p < 0.001). Preoperative radiotherapy (OR 0.51, p < 0.001) and higher pathologic stage (OR 0.37, stage III, p < 0.001) were negative predictors. In patients with nonirradiated pathologic stage 0-I cancers, SP rates also increased, but 25 % of these patients underwent non-SP procedures. Within this subset, patients with clinical stage 0 and I disease still had significant rates of abdominoperineal resection (7.7 and 17.0 %, respectively).

CONCLUSIONS

SP rates among veterans have increased and surpass national rates. However, an unacceptable proportion of patients with stage 0-I rectal cancers still undergo non-SP procedures. Multimodal treatment with local excision may further improve SP rates in this subset of patients.