Outcomes of multimodality therapies for patients with stage II or III rectal cancer in California, 1994-2009.

BACKGROUND: Perioperative chemoradiotherapy is being used for the treatment of locally advanced rectal cancer to improve survival and reduce recurrence. Although several studies have prompted these changes, the survival benefits of additional chemoradiotherapy have not been adequately tested in a large-scale, population-based setting. OBJECTIVE: The purpose of this study was to evaluate survival differences between perioperative chemoradiotherapy and surgery alone for the treatment of rectal cancer. DESIGN: : This was a nonconcurrent cohort study of patients treated for rectal cancer stages II and III between 1994 and 2009. SETTING: The study was conducted through the California Cancer Registry. PATIENTS: Eligible patients were those with rectal cancer stage II or III who received either radical surgery alone (N = 2988) or perioperative chemoradiotherapy (N = 8852) during the study period. MAIN OUTCOME MEASURES: Cox proportional hazards regression was used to assess the risk of mortality associated with perioperative chemoradiotherapy versus surgery alone, adjusting for age, sex, race/ethnicity, socioeconomic status, tumor stage, month/year of surgery, and hospital factors. RESULTS: In multivariable binomial log-linear regression, the adjusted prevalence ratio (PR) for receiving perioperative chemoradiotherapy was lower among patients in the older age groups, especially among those ≥75 years of age (PR = 0.52 [95% CI, 0.49-0.55]), and increased monotonically from lowest (PR = 0.92 [95% CI, 0.89-0.95]) to highest socioeconomic status group (referent). Multivariable Cox proportional hazards regression analysis, adjusting for demographic factors, tumor stage, and hospital identification number, showed that perioperative chemoradiotherapy, relative to surgery alone, was associated with lower mortality during the entire study period, with survival benefit increasing over time (1994-1997: HR = 0.76 [95% CI, 0.66-0.88]; 1998-2001: HR = 0.71 [95% CI, 0.64-0.79]; 2002-2005: HR = 0.63 [95% CI, 0.55-0.71]; 2006-2008: HR = 0.47 [95% CI, 0.39-0.56]). LIMITATIONS: No information was available on comorbidities or specific surgeon factors, which could contribute to survival differences. CONCLUSIONS: Perioperative chemoradiotherapy, compared with surgery alone, was associated with significantly improved survival during the entire study period, with increasing benefit among those treated during the latter years of our studied time period. (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A120).

Predictors of delayed-stage colorectal cancer: are we neglecting critical demographic information?

PURPOSE: We sought to distinguish roles of demographic variables and bowel segments as predictors of delayed versus early stage colorectal cancer in California. METHODS: Demographic and anatomic variables for 66,806 colorectal cancers were extracted from the California Cancer Registry for 2004-2008 and analyzed using logistic regression as delayed versus early stage. RESULTS: Odds ratios (OR) for binary stage categories comparing age <40 (OR=2.58; 95% CI=2.26-2.94), 40-49 (1.71; 95%=1.60-1.83) and 75+ (1.05; 1.02-1.09) relative to 50-74 years were computed. Compared with non-Hispanic whites, ORs for stage categories were: 1.05; 0.99-1.13 (non-Hispanic blacks), 1.08; 1.02-1.13 (Hispanics), and 1.05; 1.00-1.10 (Asian/others). Females had higher odds of delayed diagnosis (1.09; 1.06-1.13) than males. Descending ORs were measured for successively lower to highest socioeconomic status (SES) quintiles (OR 4:5=1.08; 1.03-1.14, OR 3:5=1.13; 1.08-1.19, OR 2:5=1.18; 1.12- 1.24, and OR 1:5=1.21; 1.14-1.28). CONCLUSIONS: Younger and older than age 50-74; females; Hispanic ethnicity; bowel segment contrasts (right/left, proximal/distal, cecum plus appendix/distal), and lower SES were independent predictors of delayed diagnosis. Low SES was the most robust predictor of delayed diagnosis, independent of other covariates. Approximately 77% of delayed diagnoses were in non-Hispanic whites and Asian/others. These findings illustrate the value of a community SES index for targeting egalitarian colorectal cancer screening.