A Case of Diffuse Large B Cell Lymphoma of the Breast with Predominantly High-Level Internal Echoes

Metastatic lymph nodes of occult breast cancer show very low internal echoes

A 62-year-old woman showed an elevation of carcinoembryonic antigen (CEA) level 15 years after the left breast cancer, i.e., tubule forming type luminal micro invasive cancer, operation. Positron emission tomography/computed tomography (PET/CT) showed avid radio-tracer uptake in her right axillary and supraclavicular lymph nodes. Mammography, ultrasound (US), PET/CT, and magnetic resonance imaging showed no abnormalities in her right breast. US of the enlarged lymph nodes showed very low internal echoes. Pathological study using a core needle biopsy specimen of a right axillary node showed human epidermal growth factor receptor type 2 (HER2) positive atypical cells growing in solid and trabecular fashions. Under the presumed diagnosis of right occult breast cancer, the patient received anti-HER2 agents-containing chemotherapy, leading to marked shrinkage of the enlarged lymph nodes with normalization of the elevated CEA level. To confirm the pathological efficacy, sentinel plus sampling node biopsy was done to the patient. Postoperative pathological study of the resected nodes showed fibrosis and no viable cancer cells. The patient further received radiotherapy both to the right breast and suprarclavicular region followed by adjuvant anti-HER2 agents therapy, and has been well without any recurrences for 39 months. Diagnostic physicians should note that metastatic lymph nodes of occult breast cancer show very low internal echoes.

Surgery to Oligometastatic Breast Cancer after Excellent Response to Palbociclib and Letrozole Therapy: Pitfall of Ultrasound Therapeutic Evaluation

A 48-year-old woman with regional recurrences of breast cancer in the axillar and supraclavicular regions was referred to our hospital. Under the diagnosis of recurrent luminal breast cancer with a high Ki-67 labeling index of >30% and a disease-free interval of 13 years, the patient began to receive palbociclib, letrozole, and luteinizing hormone-releasing hormone agonist, resulting in marked response of the supraclavicular lesion and stable disease of the axillar lesion on ultrasound (US) evaluation. Positron emission tomography (PET)/computed tomography of the axillar and supraclavicular foci showed high and no avidities before and after treatment, respectively. The unmovable neck lesion became movable with the treatment. The patient, therefore, underwent surgical resection of the 2 metastatic foci to examine the discordant therapeutic efficacy against the 2 metastatic foci on 2 image modalities, that is, US and PET, and to possibly get a cure of the breast cancer oligometastasis. Pathological examination showed marked fibrosis and scant cancer cell residuals with microcalcifications in the neck tumor and massive sarcoid-like reaction with scant cancer cell residuals in the axillary nodes. The residual cancer cells showed estrogen and progesterone receptor positivities, human epidermal growth factor receptor type 2 negativity, and an extremely low Ki-67 labeling index of 2.5%. The patient recovered uneventfully and has continued palbociclib-containing endocrine therapy for 1 year without any recurrences. Breast oncologists should well understand the basic principles of internal echo formation on US and take the presence of sarcoid-like reaction in the cancer cell clusters into consideration on the therapeutic evaluation of metastatic breast cancer.