Are we undertreating rectal cancer in the elderly? An epidemiologic study.
OBJECTIVE
To better understand the reasons for decreased survival rates in elderly patients with rectal cancer by performing an epidemiologic evaluation of age-related differences in treatment and survival.


BACKGROUND
The incidence of rectal cancer increases with older age, and localized disease can be curatively treated with stage-appropriate radical surgery. However, older patients have been noted to experience decreased survival.


METHODS
Patients with localized rectal adenocarcinoma were identified in the Surveillance, Epidemiology, and End Results database (1991-2002). Cancer-specific survival by age, sex, surgery type, tumor grade, lymph node status, and use of radiation therapy was evaluated using univariate and multivariate regression analysis.


RESULTS
We identified 21,390 patients who met the selection criteria. The median age was 68 years. Each half-decade increase in age > or =70 years was associated with a 37% increase in the relative risk (RR) for cancer-related mortality (RR = 1.37; 95% confidence interval [CI], 1.33-1.42); decreased receipt of cancer-directed surgery (odds ratio [OR] = 0.56; 95% CI, 0.36-0.63); more local excision and less radical surgery (OR = 0.76; 95% CI, 0.72-0.81); less radiotherapy (OR = 0.64; 95% CI, 0.61-0.67); and greater likelihood of N0 pathologic stage classification (OR = 1.10; 95% CI, 1.05-1.15) (P < 0.0001 for each factor). The effect of age on cancer-specific mortality persisted in multivariate analysis with each half-decade increase in age > or =70 years resulting in a 31% increase in cancer-specific mortality (RR = 1.31; 95% CI, 1.25-1.36; P < 0.0001).


CONCLUSIONS
In elderly patients, rectal cancer is characterized by decreased cancer-related survival rates that are associated with less aggressive treatment overall and decreased disease stages at presentation. Investigation into the reasons for these treatment differences may help to define interventions to improve cancer outcomes.
Department of Surgical Oncology, University of Texas, M.D. Anderson, Cancer Center, Houston, TX 77030, USA. gchang@mdanderson.org
George J
GJ
Chang
John M
JM
Skibber
Barry W
BW
Feig
Miguel
M
Rodriguez-Bigas
D000230:Adenocarcinoma / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D000367:Age Factors; D000368:Aged; D003082:Colectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011379:Prognosis; D012004:Rectal Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D018426:SEER Program / Q000706:statistics & numerical data; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology