Paraneoplastic cerebellar degeneration due to anti-Yo antibodies.
Metastatic poorly differentiated carcinoma, involving a right axillary lymph node, consistent with metastasis from a primary cancer in the breast (estrogen receptor negative and progesterone receptor negative, with overexpression of HER2/neu).
Figure 1. Imaging Studies.
A sagittal T1-weighted MRI scan obtained on the patient's admission to this hospital (Panel A) shows shrinkage of the cerebellar vermis (arrow). A PET scan obtained after the administration of 18F-fluorodeoxyglucose (Panel B) shows a small focus of uptake in the left axilla and a slightly larger one in the right axilla (arrows). A follow-up PET scan obtained 4 months later (Panel C) shows extensive abnormal uptake of tracer in the region of the right axilla and chest wall (arrow).