Impact of Cancer Diagnosis and Chemotherapy on Mammography Use
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Transcript of Impact of Cancer Diagnosis and Chemotherapy on Mammography Use
Impact of Cancer Diagnosis and Chemotherapy on Mammography Use
Xinhua Yu, M.B., Ph.D.
A. Marshall McBean, M.D., M.Sc.Beth A. Virnig, Ph.D., M.P.H
Division of Health Policy and ManagementUniversity of Minnesota
Annual Research Meeting: June 9, 2008
Introduction Colorectal cancer is the second leading cancer cause of death in
the US Average age of diagnosis: 71 Life expectancy for elderly women at age 65: 20 years 39% localized stage, and 36% regional stage Relative five year survival rates: 90% for localized, 68% for regional
stage In 2005, over 1 million colorectal cancer survivors, 563,408 women Treatment: surgery, radiation, and chemotherapy
Chemotherapy not recommended for stage I and II colon cancer A second primary cancer is becoming a significant problem among
cancer survivors No evidence of differences in the risk of breast cancer between
female colorectal cancer survivors and women with no history of cancer
Hypotheses Patient’s health belief and behavior may play a significant
role in receiving chemotherapy and mammograms Patients with proactive health behavior are more likely to receive
mammograms and chemotherapy
Mammography use among newly diagnosed colorectal cancer patients will decrease after the cancer diagnosis because of the competing demands of cancer management
Data Source Linked SEER-Medicare data, 2006 batch Women diagnosed of stage 0, I, II, and III colorectal cancer from
1996 to 2001 Unstaged cancer cases were excluded
Aged 67-79 at the time of cancer diagnosis Cost-effectiveness of mammography use Chemotherapy use is lower among patients older than 80
Each cancer patient was matched up to 5 non-cancer controls by age, race, state residence
The time windows before and after the cancer diagnosis were aligned between cancer patients and non-cancer controls
Chemotherapy was identified using both administrative and agents claims Restricted to chemotherapy within one year
Analysis Analysis is based on the matched design Important co-variables include race, age, hospital type, state
buy-in status, zip code median household income, Charlson score, medical oncologist visit, and cancer stage
Stratified by prior mammography use and chemotherapy use Patterns of mammography use after the cancer diagnosis
Survival curves for the time to the first mammogram and cumulative mammography rates
Mammography rates during the third and fourth year after the cancer diagnosis Conditional logistic regression
Results
Comparison of Characteristics between Cancer Patients and Matched controls Cancer patients
Non-cancer controls
(8,294) (38,992)
Age Mean (SD) 73.6 (3.7) 73.7 (3.5) p=0.0004
67-69 16.6% 19.2% p <0.001
70-74 37.5% 36.1%
75-79 45.9% 44.7%
Race/ethnicity White 85.5% 85.7%
Black 7.7% 7.5%
Other 6.8% 6.8%
State buy-in status yes 19.0% 19.2%
Zip code median <38,000 32.0% 28.4% p <0.001
household income 38,001-50,000 36.9% 34.9%
50,001+ 31.1% 36.8%
Charlson score 0 31.6% 40.7% p <0.001
1 33.5% 29.2%
2 18.0% 15.6%
3+ 17.0% 14.6%
Chemotherapy Use by Prior Mammography Use among Women with Colorectal cancer
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
0/I II III
AJCC stage
Ch
em
oth
era
py
ra
te
Mammogram No
Mammogram Yes
Mammography Rates during the Third and Fourth Year after the Cancer Diagnosis among Women, by Chemotherapy Status
After cancer diagnosis
Chemotherapy Cancer
patientsNon-cancer
controls Odds Ratio (95% CI)
Yes 58.8% 50.5% 1.17 (1.10 - 1.25)
No 52.8% 50.2% 1.05 (1.01 - 1.10)
Total 54.9% 50.3% 1.10 (1.06 - 1.13)
Mammography Rates during the Third and Fourth Year after the Cancer Diagnosis among Women Having a Prior Mammogram
AJCC stage ChemotherapyCancer
patientsNon-cancer
controlsOdds Ratio (95%
CI)
0/I Yes 77.9% 68.1% 1.18 (0.87-1.59)
No 73.1% 71.7% 1.02 (0.93-1.17)
II Yes 77.5% 73.9% 1.02 (0.90-1.16)
No 67.9% 71.2% 0.97 (0.87-1.07)
III Yes 75.2% 70.7% 1.09 (0.97-1.22)
No 52.4% 68.0% 0.75 (0.54-1.04)
AJCC stage Chemotherapy
Cancer patients
Non-cancer controls
Odds Ratio (95% CI)
0/I Yes 48.9% 30.9% 1.57 (1.06-2.33)
No 38.4% 30.6% 1.28 (1.16-1.41)
II Yes 45.4% 32.4% 1.47 (1.26-1.74)
No 31.5% 29.5% 1.06 (0.92-1.21)
III Yes 45.4% 32.1% 1.46 (1.27-1.68)
No 22.1% 28.3% 0.71 (0.50-0.99)
Mammography Rates during the Third and Fourth Year after the Cancer Diagnosis among Women NOT Having a Prior Mammogram
Conclusion Chemotherapy rate was higher among those who had
mammography use before the cancer diagnosis than those who did not
A new cancer diagnosis and chemotherapy treatment may reduce mammography use among some patients with advanced cancer stages
The mammography rate after the cancer diagnosis increased among patients with less advanced cancer stages
Those with prior mammograms consistently had higher mammography rates after cancer diagnosis
Among those without prior mammograms, the differences in mammography rates after cancer diagnosis were even greater
Discussion Competing demands exist between cancer management and
mammography use, as seen in those with stage III disease Among those with less advanced cancer stage, the increase
of mammography use may be due to the enhanced positive health beliefs or the favorable change of heath beliefs among these patients
Given the high survival rate and long life-expectancy among colorectal cancer patients, providers should continue to recommend mammograms to them
Thank You!