Mantle Cell Lymphoma Presenting as a Subcutaneous Soft Tissue Mass With an Unusual Appearance

CLINICAL HISTORYThe patient is a 61-year-old man with a medical history of hypertension who originally presented for an ultrasound of a right lower-back mass, which had been growing for 2 weeks. A magnetic resonance imaging (MRI) was initially recommended based on the ultrasound appearance. However,