TY - JOUR
T1 - Relative impact of earlier diagnosis and improved treatment on survival for colorectal cancer
T2 - A US database study among elderly patients
AU - Tong, Liyue
AU - Ahn, Chul
AU - Symanski, Elaine
AU - Lai, Dejian
AU - Du, Xianglin L.
N1 - Publisher Copyright:
© 2014 Elsevier Ltd.
PY - 2014/12/1
Y1 - 2014/12/1
N2 - Purposes: To estimate what proportion of improvement in relative survival was attributable to smaller stage/size due to early detection and what proportion was attributable to cancer chemotherapy in patients with colorectal cancer (CRC) Methods: We studied 69,718 patients with CRC aged ≥66 years in 1992-2009 from Surveillance, Epidemiology, and End Results registriesStudy periods were categorized into three periods according to the major changes or advances in screening and chemotherapy regimens: (1) Period-1 (1992-1995), during which there was no evidence-based recommendation for routine CRC screening and 5-fluorouracil was the mainstay for chemotherapy; (2) Period-2 (1996-2000), during which evidences and guidelines supported the use of fecal occult blood test (FOBT) and sigmoidoscopy for routine CRC screening; and (3) Period-3 (2001-2009), during which Medicare Program added the full coverage for colonoscopy screening to average-risk individuals, and several newly developed chemotherapy regimens were approvedOutcome variables included the likelihood of being diagnosed at an early stage or with a small tumor size, and improvement in relative survival Results: Compared to period-1, likelihood of being diagnosed with early stage CRC increased by 20% in period-2 (odds ratio=1.2, 95%CI: 1.1-1.2) and 30% in period-3 (1.3, 1.2-1.4); and likelihood of being diagnosed with small-size CRC increased by 60% in period-2 and 110% in period-3Similarly, 5-year overall relative survival increased from 51% in period-1 to 56% in period-2 and 60% in period-3Increase in survival attributable to migration in stage/size was 9% in period-2 and 20% in period-3, while the remaining survival improvement during period-2 and period-3 were largely attributable to more effective chemotherapy regimens (≥71.6%) and other treatment factors (≤25%) Conclusions: Improvements in CRC screening resulted in a migration of CRC toward earlier tumor stage and smaller size, which contributed to ≤20% of survival increaseSurvival improvement over the past 2 decades was largely explained by more effective chemotherapy regimens (≥71.6%)
AB - Purposes: To estimate what proportion of improvement in relative survival was attributable to smaller stage/size due to early detection and what proportion was attributable to cancer chemotherapy in patients with colorectal cancer (CRC) Methods: We studied 69,718 patients with CRC aged ≥66 years in 1992-2009 from Surveillance, Epidemiology, and End Results registriesStudy periods were categorized into three periods according to the major changes or advances in screening and chemotherapy regimens: (1) Period-1 (1992-1995), during which there was no evidence-based recommendation for routine CRC screening and 5-fluorouracil was the mainstay for chemotherapy; (2) Period-2 (1996-2000), during which evidences and guidelines supported the use of fecal occult blood test (FOBT) and sigmoidoscopy for routine CRC screening; and (3) Period-3 (2001-2009), during which Medicare Program added the full coverage for colonoscopy screening to average-risk individuals, and several newly developed chemotherapy regimens were approvedOutcome variables included the likelihood of being diagnosed at an early stage or with a small tumor size, and improvement in relative survival Results: Compared to period-1, likelihood of being diagnosed with early stage CRC increased by 20% in period-2 (odds ratio=1.2, 95%CI: 1.1-1.2) and 30% in period-3 (1.3, 1.2-1.4); and likelihood of being diagnosed with small-size CRC increased by 60% in period-2 and 110% in period-3Similarly, 5-year overall relative survival increased from 51% in period-1 to 56% in period-2 and 60% in period-3Increase in survival attributable to migration in stage/size was 9% in period-2 and 20% in period-3, while the remaining survival improvement during period-2 and period-3 were largely attributable to more effective chemotherapy regimens (≥71.6%) and other treatment factors (≤25%) Conclusions: Improvements in CRC screening resulted in a migration of CRC toward earlier tumor stage and smaller size, which contributed to ≤20% of survival increaseSurvival improvement over the past 2 decades was largely explained by more effective chemotherapy regimens (≥71.6%)
KW - Chemotherapy
KW - Colorectal cancer
KW - Survival
KW - Tumor stage and size migration
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U2 - 10.1016/j.canep.2014.10.004
DO - 10.1016/j.canep.2014.10.004
M3 - Article
C2 - 25454261
AN - SCOPUS:84912127484
SN - 1877-7821
VL - 38
SP - 733
EP - 740
JO - Cancer Epidemiology
JF - Cancer Epidemiology
IS - 6
ER -