Breast cancer recurrence following active treatment: Determining its incidence in the NSW population

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Objectives: It is important for consumers, clinicians and health service planners to know the risk of recurrence of primary breast cancer after initial treatment. At present, none of Australia's state or territory cancer registries routinely report this information. We aimed to determine the incidence of recurrence in New South Wales (NSW) clinical practice for the period 18 months to 6 years after diagnosis of primary breast cancer. Study type: Retrospective cohort study using population-based linked health data. Methods: We identifed 2416 women in the 45 and Up Study who were diagnosed with primary invasive breast cancer between 2003 and 2008 in NSW, and who had not had a recurrence 18 months after diagnosis. Unit-level hospital, pharmacy and outpatient medical claims were used to identify treatment for recurrence. Incidence of recurrence was calculated using individual person-time at risk (18 months to 6 years postdiagnosis), with follow-up censored for death or end of study period (median follow-up 3 years). Time to recurrence was calculated, and Cox proportional regression was used to identify women's baseline and active treatment characteristics that were predictive of recurrence up to 6 years postdiagnosis. Results: 217 women (9%) had a hospital, pharmacy or outpatient claim indicating breast cancer recurrence. Overall annual incidence of recurrence was 3.3%. Recurrence rates were signifcantly higher for women with nodepositive (4.8% vs 2.5% annually; hazard ratio [HR] = 1.7; 95% confdence interval [95% CI] 1.3, 2.3) or hormone receptor-negative tumours (3.8% vs 3.1% annually; HR = 1.3; 95% CI 1.0, 1.7). Women with tumours >2 cm at diagnosis were more likely to experience recurrence than women with smaller/unknown tumours (4.8% vs 2.7% annually; HR = 1.5; 95% CI 1.1, 2.0). Conclusions: A combination of routinely collected administrative health datasets can be used to determine recurrence rates, allowing future assessment of population-level changes over time and investigations of the real-world impact of specifc treatments on outcomes.

Original languageEnglish
Article numbere2611607
Journal Public Health Research & Practice
Volume26
Issue number1
DOIs
Publication statusPublished - 28 Jan 2016

Fingerprint

New South Wales
Breast Neoplasms
Recurrence
Incidence
Population
Therapeutics
Neoplasms
Outpatients
Hospital Units
Health
Health Services
Registries
Cohort Studies
Retrospective Studies

Cite this

@article{1c7ba984e4a24807b3bbbf86e5a9aca4,
title = "Breast cancer recurrence following active treatment: Determining its incidence in the NSW population",
abstract = "Objectives: It is important for consumers, clinicians and health service planners to know the risk of recurrence of primary breast cancer after initial treatment. At present, none of Australia's state or territory cancer registries routinely report this information. We aimed to determine the incidence of recurrence in New South Wales (NSW) clinical practice for the period 18 months to 6 years after diagnosis of primary breast cancer. Study type: Retrospective cohort study using population-based linked health data. Methods: We identifed 2416 women in the 45 and Up Study who were diagnosed with primary invasive breast cancer between 2003 and 2008 in NSW, and who had not had a recurrence 18 months after diagnosis. Unit-level hospital, pharmacy and outpatient medical claims were used to identify treatment for recurrence. Incidence of recurrence was calculated using individual person-time at risk (18 months to 6 years postdiagnosis), with follow-up censored for death or end of study period (median follow-up 3 years). Time to recurrence was calculated, and Cox proportional regression was used to identify women's baseline and active treatment characteristics that were predictive of recurrence up to 6 years postdiagnosis. Results: 217 women (9{\%}) had a hospital, pharmacy or outpatient claim indicating breast cancer recurrence. Overall annual incidence of recurrence was 3.3{\%}. Recurrence rates were signifcantly higher for women with nodepositive (4.8{\%} vs 2.5{\%} annually; hazard ratio [HR] = 1.7; 95{\%} confdence interval [95{\%} CI] 1.3, 2.3) or hormone receptor-negative tumours (3.8{\%} vs 3.1{\%} annually; HR = 1.3; 95{\%} CI 1.0, 1.7). Women with tumours >2 cm at diagnosis were more likely to experience recurrence than women with smaller/unknown tumours (4.8{\%} vs 2.7{\%} annually; HR = 1.5; 95{\%} CI 1.1, 2.0). Conclusions: A combination of routinely collected administrative health datasets can be used to determine recurrence rates, allowing future assessment of population-level changes over time and investigations of the real-world impact of specifc treatments on outcomes.",
author = "Anna Kemp-Casey and Roughead, {Elizabeth E.} and Christobel Saunders and Frances Boyle and Derrick Lopez and Mahesh Bulsara and Preen, {David B.}",
year = "2016",
month = "1",
day = "28",
doi = "10.17061/phrp2611607",
language = "English",
volume = "26",
journal = "Public Health Research & Practice",
issn = "2204-2091",
publisher = "The Sax Institute",
number = "1",

}

TY - JOUR

T1 - Breast cancer recurrence following active treatment

T2 - Determining its incidence in the NSW population

AU - Kemp-Casey, Anna

AU - Roughead, Elizabeth E.

AU - Saunders, Christobel

AU - Boyle, Frances

AU - Lopez, Derrick

AU - Bulsara, Mahesh

AU - Preen, David B.

PY - 2016/1/28

Y1 - 2016/1/28

N2 - Objectives: It is important for consumers, clinicians and health service planners to know the risk of recurrence of primary breast cancer after initial treatment. At present, none of Australia's state or territory cancer registries routinely report this information. We aimed to determine the incidence of recurrence in New South Wales (NSW) clinical practice for the period 18 months to 6 years after diagnosis of primary breast cancer. Study type: Retrospective cohort study using population-based linked health data. Methods: We identifed 2416 women in the 45 and Up Study who were diagnosed with primary invasive breast cancer between 2003 and 2008 in NSW, and who had not had a recurrence 18 months after diagnosis. Unit-level hospital, pharmacy and outpatient medical claims were used to identify treatment for recurrence. Incidence of recurrence was calculated using individual person-time at risk (18 months to 6 years postdiagnosis), with follow-up censored for death or end of study period (median follow-up 3 years). Time to recurrence was calculated, and Cox proportional regression was used to identify women's baseline and active treatment characteristics that were predictive of recurrence up to 6 years postdiagnosis. Results: 217 women (9%) had a hospital, pharmacy or outpatient claim indicating breast cancer recurrence. Overall annual incidence of recurrence was 3.3%. Recurrence rates were signifcantly higher for women with nodepositive (4.8% vs 2.5% annually; hazard ratio [HR] = 1.7; 95% confdence interval [95% CI] 1.3, 2.3) or hormone receptor-negative tumours (3.8% vs 3.1% annually; HR = 1.3; 95% CI 1.0, 1.7). Women with tumours >2 cm at diagnosis were more likely to experience recurrence than women with smaller/unknown tumours (4.8% vs 2.7% annually; HR = 1.5; 95% CI 1.1, 2.0). Conclusions: A combination of routinely collected administrative health datasets can be used to determine recurrence rates, allowing future assessment of population-level changes over time and investigations of the real-world impact of specifc treatments on outcomes.

AB - Objectives: It is important for consumers, clinicians and health service planners to know the risk of recurrence of primary breast cancer after initial treatment. At present, none of Australia's state or territory cancer registries routinely report this information. We aimed to determine the incidence of recurrence in New South Wales (NSW) clinical practice for the period 18 months to 6 years after diagnosis of primary breast cancer. Study type: Retrospective cohort study using population-based linked health data. Methods: We identifed 2416 women in the 45 and Up Study who were diagnosed with primary invasive breast cancer between 2003 and 2008 in NSW, and who had not had a recurrence 18 months after diagnosis. Unit-level hospital, pharmacy and outpatient medical claims were used to identify treatment for recurrence. Incidence of recurrence was calculated using individual person-time at risk (18 months to 6 years postdiagnosis), with follow-up censored for death or end of study period (median follow-up 3 years). Time to recurrence was calculated, and Cox proportional regression was used to identify women's baseline and active treatment characteristics that were predictive of recurrence up to 6 years postdiagnosis. Results: 217 women (9%) had a hospital, pharmacy or outpatient claim indicating breast cancer recurrence. Overall annual incidence of recurrence was 3.3%. Recurrence rates were signifcantly higher for women with nodepositive (4.8% vs 2.5% annually; hazard ratio [HR] = 1.7; 95% confdence interval [95% CI] 1.3, 2.3) or hormone receptor-negative tumours (3.8% vs 3.1% annually; HR = 1.3; 95% CI 1.0, 1.7). Women with tumours >2 cm at diagnosis were more likely to experience recurrence than women with smaller/unknown tumours (4.8% vs 2.7% annually; HR = 1.5; 95% CI 1.1, 2.0). Conclusions: A combination of routinely collected administrative health datasets can be used to determine recurrence rates, allowing future assessment of population-level changes over time and investigations of the real-world impact of specifc treatments on outcomes.

UR - http://www.scopus.com/inward/record.url?scp=84994169044&partnerID=8YFLogxK

U2 - 10.17061/phrp2611607

DO - 10.17061/phrp2611607

M3 - Article

VL - 26

JO - Public Health Research & Practice

JF - Public Health Research & Practice

SN - 2204-2091

IS - 1

M1 - e2611607

ER -