Utilization and determinants of adjuvant therapy among older patients who receive curative surgery for pancreatic cancer.
OBJECTIVE
We conducted a population-based study to describe the utilization, determinants, and survival effects of adjuvant therapies after surgery among older patients with pancreatic cancer.


METHODS
Using Surveillance, Epidemiology, and End Results-Medicare data, we identified patients older than 65 years who received surgical resection for pancreatic cancer during 1992-2002. We constructed multiple logistic regression models to examine patient, clinical, and hospital factors associated with receiving adjuvant therapy. Cox proportional hazards models were used to examine the effect of therapy on survival.


RESULTS
Approximately 49% of patients received adjuvant therapy after surgery. Patient factors associated with increased receipt of adjuvant therapy included more recent diagnosis, younger age, stage II disease, higher income, and geographic location. Hospital factors associated with increased receipt of adjuvant therapy included cooperative group membership and larger size. Adjuvant treatments associated with a significant reduction in 2-year mortality (relative to surgery alone) were chemoradiation or radiation alone but not chemotherapy alone.


CONCLUSIONS
Our findings suggest that adjuvant chemoradiation and, to a lesser degree, radiation only are associated with a reduction in the risk of mortality among older patients who undergo surgery for pancreatic cancer. However, receipt of adjuvant therapy varied by period and geography as well as by certain patient and hospital factors.
Davila
Jessica A
JA
Sections of Health Services Research, The Houston Veterans Affairs Medical Center, Baylor College of Medicine, Houston, TX, USA. jdavila@bcm.tmc.edu
Chiao
Elizabeth Y
EY
Hasche
Jennifer C
JC
Petersen
Nancy J
NJ
McGlynn
Katherine A
KA
Shaib
Yasser H
YH
D000367:Age Factors; D000368:Aged; D017024:Chemotherapy, Adjuvant / Q000706:statistics & numerical data; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D007182:Income / Q000706:statistics & numerical data; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D006278:Medicare; D009367:Neoplasm Staging; D010180:Pancreatectomy / Q000706:statistics & numerical data*; D010190:Pancreatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D018579:Patient Selection; D016016:Proportional Hazards Models; D018714:Radiotherapy, Adjuvant / Q000706:statistics & numerical data; D012111:Residence Characteristics / Q000706:statistics & numerical data; D012189:Retrospective Studies; D018570:Risk Assessment; D018426:SEER Program; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology
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