Invasive lobular carcinoma stable for 4.5 years in a postmenopausal woman user of hormone therapy for 25 years.

We present a case of a 72-year-old woman referred to the breast disorder service due to abnormalities on mammography and breast ultrasound. The patient reported using different hormone therapy (HT) formulations during 25 years and had stopped taking HT for 4 years. Physical examination showed no alterations in the breasts or axilla. Mammography from 2012 detected asymmetry at the 3 o'clock position in the anterior right breast. Ultrasound revealed an irregular, hypoechoic mass with indistinct margins, and posterior acoustic shadowing. A retrospective analysis of mammographies from 2007, 2009 and 2010 showed that a very subtle asymmetry had existed since 2007. Follow-up imaging demonstrated no change in asymmetry during 4.5 years. The patient underwent breast-conserving therapy and sentinel lymph node biopsy. Histopathologic examination demonstrated classic invasive lobular carcinoma. There were no sentinel node metastases. The patient received radiotherapy and endrocrine therapy. This case demonstrates that breast cancer may remain stable and not grow for many years. This aspect should be kept in mind by all professionals dealing with women's healthcare, in particular HT users who may develop breast cancer with a less aggressive behavior. Any suspicious finding on mammography, despite being unchanged for a number of years, must be investigated.