Open AccessDelays on Breast Cancer Treatment in Brazil: Implications on Survival
Author(s) -
I.F.d. Silva,
Simone Monteiro,
Rosalina Jorge Koifman
Publication year - 2018
Publication title -
journal of global oncology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.002
H-Index - 17
ISSN - 2378-9506
DOI - 10.1200/jgo.18.59700
Subject(s) - medicine , breast cancer , cohort , hazard ratio , proportional hazards model , cancer , retrospective cohort study , cancer registry , demography , log rank test , confidence interval , survival analysis , cohort study , gynecology , sociology
Background: Breast cancer survival may vary among regions in Brazil, being lower in northern and northeastern than in southern and southeastern regions. Earlier studies in developed countries have suggested that increased time intervals of care are associated with poorer chances for survival. There is a lack of studies on developing countries about the effect of time interval on survival. Aim: To estimate the effect of treatment delay on 3- and 5-years survival among women diagnosed with breast cancer treated on the National Cancer Institute in Rio de Janeiro, Brazil. Methods: A retrospective study on a cohort of 3220 women newly diagnosed with breast cancer between 2011 and 2013 was accomplished. Follow-up time was 60 months for women diagnosed in 2011-2012 (n=836), and 36 months for the whole cohort. Times from diagnose to treatment initiation were analyzed according to the Brazilian law for cancer patient treatment ( days). All data were obtained from hospital-based cancer registry and medical reports. Estimates of 3- and 5-survival were proceeded by Kaplan-Meier method. Survival curves differences were evaluated by 95% log-rank test. Crude and adjusted hazard ratios between delay on treatment initiation, age, education, stage and 1st treatment and death risk were estimated by proportional Cox regression with respective 95% confidential interval. Results: Mean time follow-up in the 2011-2012 cohort was 55.3 (± 12.7) months with median time of 60 months; while in the whole cohort mean follow-up time was 34.1 (± 6.1) months with 36 months of median time. Concerning the treatment delay, 3-years survival rates were 88.7% among women with ≤ 60 days for treatment initiation and 88% among women with delay on treatment (log-rank: 0.786); while 5-years survival rates were 85.2% among women with ≤ 60 days to treatment and 82.5% for women with delays on treatment (log-rank: 0.373). Delay on treatment (OR=0.77; 95 CI: 0.61-0.97), age ≥ 70 years old (OR=2.03; 95% CI: 1.46-2.82), late stage at diagnosis (OR=7.48; 95% CI: 2.27-24.61), and 1st treatment (OR CHEMO =2.66; 95% CI: 1.82-3.90; OR RADIATION/HORMONE =2.53; 95% CI: 1.58-4.06) were independently associated with death risk in 3 years. Death risk in 5 years is independently associated to age ≥ 70 years (OR=3.37; 95% CI: 1.89-6.00), chemotherapy as 1st treatment (OR=2.05; 95% CI: 1.04-4.03), and late stage (OR=11.14; 95% CI: 1.41-88.06). Conclusion: Delay on treatment initiation seems not influence 3- and 5-years survival rates in the studied population. However, after adjusted by age, stage, and treatment, delays on treatment initiation affected negatively the death risk in 3 years. On the other hand, 5-years death risk was independently associated with age ≥ 70 years, chemotherapy as 1st treatment, and late stage.