Organized Breast Cancer Screening Programs in Canada - Report on Program Performance in 2003 and 2004

Appendices

Appendix 3: Glossary

Asymptomatic
A woman who does not report symptoms and appears without signs of disease at screening.

Breast self-examination (BSE)
An examination of the breasts performed by the woman herself in order to learn what is normal for her own breasts and to recognize when something may be wrong.

Cancer
Includes malignant invasive and ductal carcinoma in situ (DCIS) of the breast.

Clinical breast examination (CBE)
A physical examination of the breasts performed by a trained health professional.

Diagnosis
The first pathologic or cytologic diagnosis of cancer, last known biopsy for benign cases, or last intervention before a recommendation to return to screening or return for early recall.

Ductal carcinoma in situ (DCIS)
A non-invasive tumour of the breast, arising from cells that involve only the lining of a breast duct. The cells have not spread outside the duct to other tissues in the breast.

Fine-needle aspiration biopsy
A needle is inserted into a lesion and cells are drawn out using a syringe. The cells are stained and examined by a cytologist in a laboratory to determine if there are any malignant cells.

Incident cancer
Cancer detected by a program screen after the initial screen.

In situ
Refers specifically to ductal carcinoma in situ (DCIS): a non-invasive tumour of the breast, arising from cells that involve only the lining of a breast duct. The cells have not spread outside the duct to other tissues in the breast.

Initial screen
The first Canadian screening program screen provided to a woman.

Interval cancer
Any invasive or ductal carcinoma in situ (DCIS) breast cancer diagnosed in the interval after a “normal” screening result and before the next scheduled screening examination.

Invasive cancer
Cancer cells invading beyond the basement membrane of the milk duct or lobule. A ductal carcinoma in situ component may also be present in cases of invasive cancer.

Negative screening episode
A screening episode that concludes with normal findings, including program-initiated work-up that did not reveal any cancer.

Open biopsy
Surgical removal of a breast abnormality under local anesthesia for subsequent microscopic examination by a pathologist.

Post-screen cancer
Cancers that occur after the recommended 12 or 24 months in women who do not return for their regular annual or biennial screen respectively (non-compliant cancers) or women who become symptomatic before their next regular screen (interval cancers).

Prevalent cancer
The proportion of the population with cancer at a given point in time.

Screen
Can comprise mammography, or both clinical breast examination and mammography, delivered by a program.

Screening episode (completed)
Defi ned for normal screens as the date of the last screen; for abnormal screens, the date of tissue diagnosis if biopsy is performed, the date of the last test before a return to screening or before the recommendation for repeat diagnostic imaging. A "negative screening episode" can include all follow-up, provided that the end result is negative.

Rescreening
Subsequent screening, according to policy, after initial screening under the program. This includes women who miss a scheduled round of screening.

Screen-detected cancer
Cancer detected as a result of a positive test with histologic confirmation attributed to the screening findings of the program.

Sojourn time
The time interval between the onset of detectable pre-clinical disease and symptomatic disease.

Total person-years at risk
Within a 12 or 24-month period after a negative screening episode, women are considered at risk for post-screen detected cancer. Women contribute a count in the denominator for each year or fraction of a year within the period of interest before a post-screen detected cancer or the next regular program screen.