A diagnostic mammogram is a specialized breast imaging procedure that uses low-dose X-rays to obtain detailed images of breast tissue. Its purpose is to investigate specific concerns, such as a new breast symptom or an abnormal finding detected during a routine screening mammogram. This targeted approach allows healthcare providers to closely examine areas of interest, helping to determine the nature of any changes within the breast.
How it Differs from a Screening Mammogram
A key distinction between a diagnostic mammogram and a screening mammogram lies in their intent. Screening mammograms are routine examinations performed on individuals without symptoms, aiming to detect potential breast changes early. In contrast, a diagnostic mammogram is conducted when there’s an existing reason for concern, such as a palpable lump or an unclear area on a prior screening image. During a diagnostic mammogram, the technologist typically captures more images, often including specialized views like spot compression or magnification, to focus on the area of concern. Unlike screening mammograms, where results might take days, a radiologist is often present to review images in real-time, allowing for immediate assessment and the possibility of acquiring additional views or recommending further tests during the same appointment.
Reasons for a Diagnostic Mammogram
Several specific circumstances can lead to a recommendation for a diagnostic mammogram. One common reason is the discovery of a new lump or mass in the breast or armpit. Other physical changes, such as alterations in breast size or shape, dimpling or puckering of the skin, or nipple discharge (especially if bloody or from a single nipple), also prompt this type of examination. Persistent or localized breast pain, particularly if it’s new and doesn’t resolve, can also be a reason. An abnormal or suspicious finding on a routine screening mammogram frequently leads to a diagnostic follow-up.
What to Expect During the Procedure
Before your appointment, avoid using deodorant, antiperspirant, lotions, or powders on your breasts or underarms, as these can interfere with image clarity. You will change into a gown, removing clothing and jewelry from the waist up.
The procedure involves standing in front of a specialized X-ray machine. A technologist will position one breast at a time on a platform, and a clear plastic paddle will gently compress the breast. This compression, while potentially uncomfortable, is necessary to spread out the breast tissue evenly, minimize radiation dose, and ensure clear images. The machine will then capture images from different angles.
The radiologist may request additional views, such as spot compression or magnification, to focus on specific areas. Because the radiologist often reviews images in real-time, the appointment may take longer than a screening mammogram, typically 30 minutes to an hour.
Interpreting Your Results and Next Steps
Following a diagnostic mammogram, the radiologist will interpret the images and often discuss the findings with you before you leave the facility. Results are typically communicated using the Breast Imaging Reporting and Data System (BI-RADS), a standardized scoring system that categorizes findings from 0 to 6.
A score of BI-RADS 0 means additional imaging or comparison with previous mammograms is needed, while BI-RADS 1 indicates a negative, normal result. BI-RADS 2 means a benign (non-cancerous) finding was identified, and BI-RADS 3 suggests a probably benign finding with a very low chance of cancer, usually recommending a follow-up in six months. Higher scores, like BI-RADS 4 or 5, indicate suspicious findings that may require further investigation, such as an ultrasound, MRI, or a biopsy.
Most diagnostic mammograms do not reveal cancer; only a small percentage of call-backs result in a cancer diagnosis. Your healthcare provider will discuss the BI-RADS score and recommend the appropriate next steps based on your specific results.