Muscle lymphoma

Muscle lymphoma is a rare manifestation of lymphoma.

Epidemiology

Muscle lymphoma is rare, representing <2% of all lymphomas. The average age of presentation is 70 years .

Clinical presentation

Focal swelling and/or pain along with B-type symptoms . Any muscle can be involved but most commonly :

  • thigh
  • trunk
  • upper limb
  • leg

Pathology

Muscle lymphoma is typically the non-Hodgkin type. It can manifest in two ways :

  • metastatic spread from primary disease (e.g. nodal, osseous)
  • primary lesion (i.e. primary muscle lymphoma), which is less common
Risk factors

Radiographic features

MRI

Muscle enlargement with focal mass or diffuse abnormal signal :

  • T1: iso- or hyperintense to normal muscle
  • T2: intermediate signal intensity to fat and muscle
  • Gad (C+): diffuse (more common), thick peripheral and/or septal marginal enhancement

Differential diagnosis

Other soft tissue tumors should be considered :

Infection (pyomyositis) should also be considered.