Long term follow up of a breast abnormality leading to the diagnosis of pleomorphic invasive lobular carcinoma based on imaging changes

Background : Invasive lobular carcinoma (ILC) is often difficult to diagnose because of subtle imaging findings and occasional false-negative biopsy results. Case presentation : A woman was initially referred for further evaluation because of marked breast asymmetry detected during screening. At the initial presentation, ultrasonography revealed an indistinct hypoechoic area, and core needle biopsy demonstrated mastopathy. Twelve years after the initial presentation, screening again prompted evaluation, and repeat core needle biopsy also showed mastopathy; therefore, the patient was returned to routine screening. Fourteen years after the initial presentation, follow-up ultrasonography demonstrated an increased depth–width ratio and newly detected internal vascularity. Vacuum-assisted biopsy was subsequently performed, leading to the diagnosis of pleomorphic invasive lobular carcinoma with loss of E-cadherin expression. Conclusion : Longitudinal imaging assessment, including subtle ultrasonographic changes such as depth–width ratio, may facilitate earlier detection of ILC.