It’s not unusual for radiologists reviewing prior breast imaging exams to discover cancers that went missed the first time around. Such circumstances can and should provide a valuable learning opportunity, according to the authors of an article running in the November-December edition of Current Problems in Diagnostic Radiology.
Citing several studies showing that around one-third of newly diagnosed cancers are, in fact, visible in retrospect on the prior mammogram, Anubha Wadhwa, MD, and colleagues at the Medical college of Wisconsin describe some common culprits behind many a missed breast cancer.
These include not only perception errors and poor technique but also misinterpretation of malignancy as benign, dense breast tissue’s masking effect, invasive lobular cancer (a particular false-negative offender), developing asymmetries and unrecognized discordance between imaging features and pathology from core needle biopsy.
To reckon with such potentially hazardous pitfalls, the authors encourage breast radiologists to keep some key imperatives top of mind. These include:
- Pay attention to the subtle features of malignancy, both on mammography and ultrasound.
- Do not make a diagnosis on a screening mammogram. Always obtain adequate diagnostic work-up such as magnification views, spot compression views or ultrasound.
- If a finding catches your attention on the mammogram, look at multiple prior mammograms to evaluate for a possible subtle developing change.
- A developing asymmetry merits a tissue diagnosis, especially if there are associated microcalcifications or architectural distortion, or if the finding is palpable.
- Be very particular about patient positioning and proper exam technique.
Wadhwa and co-authors further urge their peers to always act on the most worrisome feature of any given lesion and to repeat core biopsy or surgical excision when a pathology result fails to explain an imaging finding.
“Studying the imaging findings of cancers that went undetected is a good learning exercise for the radiologist to identify common patterns and mistakes that lead to a missed cancer,” they write. “This allows the radiologist to improve mammographic sensitivity and overall diagnostic accuracy.”