Post-Operative Radiation Therapy for Patients with Stage I or II Breast Cancer

  • Charts and Tables

    Charts and Tables

    Figure 4.17

    Percentage of Stage I and II breast cancer patients receiving radiation following breast-conserving surgery, by province — from 2009 to 2012 diagnosis years

    “—” Data not available.
    SK: Denominator includes patients who were offered radiation therapy but declined, were treated out of province, went on to have mastectomy, were not seen at cancer centre or received radiation therapy more than 270 days following surgery.
    MB: Radiation therapy not limited to primary tumour site.
    Data include radiation therapy started within 270 days following surgery.
    Data source: Provincial cancer agencies and programs.

    Data Table

    ProvinceDiagnosis yearNumber of patientsPercent (%)Lower bound of 95% confidence intervalUpper bound of 95% confidence interval
    BC2009––––
    BC2010––––
    BC2011––––
    BC2012––––
    AB200965887.485.089.8
    AB201075087.985.790.1
    AB201181388.986.991.0
    AB201287388.586.690.5
    SK200914386.180.991.4
    SK201017884.079.088.9
    SK201115474.068.180.0
    SK201216371.565.677.4
    MB200932876.172.180.1
    MB201032075.871.779.9
    MB201138180.577.084.1
    MB201233381.277.485.0
    ON20093,08288.187.089.1
    ON20103,79579.578.480.7
    ON2011––––
    ON2012––––
    QC2009––––
    QC2010––––
    QC2011––––
    QC2012––––
    NB2009––––
    NB201022484.580.288.9
    NB201131784.580.988.2
    NB201225977.172.681.6
    NS2009––––
    NS2010––––
    NS201126086.782.890.5
    NS201226381.276.985.4
    PE20092790.079.3100.0
    PE20105385.576.794.3
    PE20113886.476.296.5
    PE20124387.878.696.9
    NL20097193.487.899.0
    NL20104583.373.493.3
    NL20117481.373.389.3
    NL20127589.382.795.9

    “—” Data not available.
    SK: Denominator includes patients who were offered radiation therapy but declined, were treated out of province, went on to have mastectomy, were not seen at cancer centre or received radiation therapy more than 270 days following surgery.
    MB: Radiation therapy not limited to primary tumour site.
    Data include radiation therapy started within 270 days following surgery.
    Data source: Provincial cancer agencies and programs.

    Figure 4.18

    Percentage of Stage I or II breast cancer patients receiving radiation following breast-conserving surgery, by age group — from 2009 to 2012 diagnosis years

    Data include AB, MB, PE and NL (provinces that submitted comparable data for all 4 years).
    Data include radiation therapy started within 270 days following surgery.
    Data source: Provincial cancer agencies and programs.

    Data Table

    Diagnosis yearPatient age groupNumber of patientsPercent (%)Lower bound of 95% confidence intervalUpper bound of 95% confidence interval
    200918-5959191.289.093.4
    200960-6936789.586.592.5
    200970-7919881.176.286.1
    200980+7146.138.254.0
    201018-5964589.587.291.7
    201060-6942892.289.894.7
    201070-7922984.279.988.5
    201080+4430.122.737.6
    201118-5971391.389.393.3
    201160-6945692.189.794.5
    201170-7922881.176.685.7
    201180+6336.429.243.6
    201218-5965889.887.692.0
    201260-6946790.087.492.6
    201270-7928084.380.488.2
    201280+8247.440.054.8

    Data include AB, MB, PE and NL (provinces that submitted comparable data for all 4 years).
    Data include radiation therapy started within 270 days following surgery.
    Data source: Provincial cancer agencies and programs.

  • About this indicator

    About this indicator

    Indicator definition

    The percentage of patients diagnosed with Stage I or II breast cancer in 2012 who received post-operative radiation therapy following breast-conserving surgery† (BCS) as per widely published treatment guidelines. Results are reported by province and age.

    Measured since

    The 2010 Cancer System Performance Report.

    Update frequency

    Every two years

    Why measure this?

    Most women diagnosed with non-metastatic breast cancer are candidates for surgery (either BCS or mastectomy).1 Mastectomy and BCS followed by radiation therapy (referred to as breast-conservation therapy) result in comparable survival outcomes. But BCS followed by radiation therapy is less invasive and is associated with lower morbidity as well as better cosmetic and psychological outcomes.1 Given that BCS (followed by radiation therapy) and mastectomy yield comparable survival outcomes, the choice of surgical procedure should be made by the patient based on a clear understanding of the risks, benefits and practical considerations associated with each choice.

    What are the key findings?

    In the 2012 diagnosis year, the percentage of patients with Stage I or II breast cancer who received radiation therapy following BCS ranged from 71.5% in Saskatchewan to 89.3% in Newfoundland and Labrador (seven provinces submitted data) (Figure 4.17).

    Patients aged 18–69 were almost twice as likely as patients aged 80 or older to receive radiation following BCS (92.4% vs. 48.9%) (Figure 4.18).

    Notes

    † Breast-conserving surgery involves complete removal of the tumour along with a margin of non-cancerous breast tissue.

    References

    1. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Breast Cancer Version 1.2016. 2015.
  • Data specifications

    Data specifications

    Definition: The percentage of patients diagnosed with stage I or II breast cancer who received post-operative radiation therapy following breast-conserving surgery (BCS)

    Numerator: Stage I and II breast cancer cases (female) starting radiation therapy within 270 days following breast-conserving surgery

    Denominator: Stage I and II breast cancer cases (female) receiving breast-conserving surgery within one year of diagnosis

    Data source: Provincial cancer agencies

    Measurement timeframe: 2009, 2010, 2011 and 2012 diagnosis years

    Stratification variables: Province, age group

    Provinces submitting data: AB, SK, MB, ON, NB, NS, PE, NL

    Province specific notes:

    • AB: For 2009, segmental resections were included as lumpectomy. For 2010/2011/2012, treatment information is based on initially planned treatment to the primary site (ACR data). The CCI codes are not used by the ACR Data, as such Breast conserving surgery has been identified by a registry surgical modality variable with values ‘lumpectomy' or ‘segmental resection'. If more than one surgical procedure is performed as a part of the initial treatment, the most definitive procedure is documented. The definition of definitive is the surgical procedure with the intent to cure. Cases with radiation therapy before surgery were excluded.
    • SK: Date of surgery was not available for cases diagnosed in 2009.
    • ON: Radiation therapy was not limited to primary tumor site.
    • MB: For 2011 and 2012, treatment intent filter was not applied. Radiation therapy was not limited to primary tumor site.
    • PE: Treatment intent filter applied for 2009, but not applied for 2010 as it was only entered part way through the year so data is missing for half of the applicable cases. For 2010, radiation therapy is limited to primary tumor site. For 2011 and 2012, malignant phylodes tumor is included.
    • NL: For 2009/2010/ 2011/2012, treatment intent filter applied and radiation therapy is limited to primary tumor site.

    Notes:

    1. Breast cases identified as ICDO3 codes: C50.0 to C50.9, AJCC group stage at Diagnosis = I or II.
    2. Exclude male and lymphoma codes M-95 to M-98. For 2010 /2011/2012, also excluded sarcoma codes (see Appendix 1), neuroendocrine carcinoma and squamous cell carcinoma.
    3. Cases for patients under 18 years of age (at diagnosis) were excluded.
    4. Breast-conserving surgery cases are identified using CCI codes: 1YM87 or 1YM88.
    5. Cases with a subsequent mastectomy within one year of breast conserving surgery were excluded, using CCI codes 1YM89 to 1YM92 in the specified time period.
    6. Resected cases included regardless of margin status (due to data limitations).
    7. Included cases which last resection date (if multiple) – diagnosis date <= 365 days, radiation start date – last resection date (if multiple) <=270 days.
  • Related indicators