A 46-year-old woman was diagnosed with right breast cancer (infiltrating ductal carcinoma, locally advanced) in April 2016. She underwent staging by positron emission tomography (PET) which revealed bilateral axillary, supraclavicular, hilar, and mediastinal lymph node metastasis and uptake in the left breast, bone, and several liver metastases with intense uptake in the pituitary. She was started with goserlin, letrazole, and denosumab.
In June 2016, she started complaining of polydipsia. She was drinking more than 5 L of water per day. Magnetic resonance imaging (MRI) of the pituitary gland confirmed pituitary metastasis, and she exhibited signs and symptoms of pituitary insufficiency and diabetes insipidus. She was treated with suprasellar radiation therapy to the pituitary in July 2016 and maintained on replacement therapy mainly with levothyroxine, hydrocortisone, and desmopressin. She also had a small metastasis to the brain detected on MRI and was treated with gamma knife radiotherapy.
In September 2016, follow-up PET showed marked improvement with near resolution of bone uptake, resolution of hepatic uptake, and decrease uptake in both breast lesions.
In December 2016, repeated MRI of the brain showed re-demonstration of the previously depicted asymmetry of the pituitary gland being relatively and mildly more prominent on the right side with mild inclination of the pituitary stalk to the right. These findings are stable since the latest MRI. The previously depicted hyperintense small foci on tbl2 and fluid-attenuated inversion recovery sequences demonstrated a stationary course with no related edema, restricted diffusion, or abnormal enhancement.
Moreover, in December 2016, PET showed hypermetabolic lesion in the right thyroid lobe for further correlation. Moderate hypermetabolic soft tissue lesion was noted in the right breast and required further evaluation. Nonfluorodeoxyglucose-avid multiple sclerotic lesions were observed at multiple levels of the thoracic and lumbar vertebrae.
She maintained the same management, and follow-up imaging continued to show improvement. During this time, the patient was clinically well.
In January 2018, follow-up PET showed clear progression of the disease with progressing neck and mediastinal lymph nodes, as well as right breast lesion and new bone lesions. At this time, the oncologist decided to start second-line treatment for premenopause as ribociclib plus fulvestrant and to continue gosrelin and denosumab. She continued to receive replacement therapy for panhypopituitarism.
She responded well to treatment. In September 2018, the latest PET showed complete metabolic resolution of the disease (Figure 1).