Unilateral breast metastasis from alveolar rhabdomyosarcoma in adult detected by ¹⁸F-FDG PET/CT.

Fig. 1 shows the images of a 44-year-old woman, who was diagnosed of an alveolar rhabdomyosarcoma of the right heel (dotted arrow in B), during her second trimester of her pregnancy. After diagnosis, she underwent delivery by elective cesarean. In the initial staging of the disease, she had an extensive lymph node involvement of inguinal, iliac and retroperitoneal territories detected by contrast-enhanced CT (prior to first FDG PET/CT), which had a good response to chemotherapy, as well as the primary tumor. During her follow up, in a 18F-FDG PET/CT, an intense focal uptake (SUVmax 5) in the superior external quadrant of the right breast (arrow in B and D) was observed, correlating with a subcentimeter nodal lesion in CT, not present in previous study (A and row C). Subsequently, this lesion was biopsied by ultrasound