The mass was found by accident. An 18-year-old woman had been admitted for viral pneumonia complicated by a staph infection, and somewhere in the workup, a clinician felt something above her left collarbone. It was causing her no symptoms at all.
Ultrasound measured it at roughly 5.9 by 4.0 by 2.1 centimeters, with sharp borders and heavy blood flow inside. A PET-CT scan showed uneven uptake and raised suspicion of a malignant lesion. A needle biopsy came back as a spindle cell tumor in which low-grade malignancy could not be excluded.
