Imaging studies of 14 patients with suspected musculoskeletal lymphoma were retrospectively reviewed.
Two patients presented with palpable mass (PML cases,
Fig.
11,
13-14),
whereas pain was the major symptom in the rest (PBL patients).
PBL was located in the extremities in 5 patients (Fig.
1-2,3-4,7),
the pelvis in 2 patients (Fig.
9-10,12) and the spine in 3 patients (Fig.
5,6,8).
Two patients presented with multifocal PBL (Fig.
6,8).
Associated soft-tissue mass was depicted in four PBL cases (Fig.
8).
X-rays showed a permeative pattern in long bone lesions with variable degrees of bone erosion (ranging from “near normal” to extensive) and periosteal reaction (Fig.
1,3-4).
CT better demonstrated soft-tissue extension and cortical involvement,
a finding often elusive on X-ray (Fig.
1,3,9).
MRI showed extensive bone-marrow involvement in all cases,
with/without soft-tissue mass or cortical disruption.
Differential diagnosis included osteosarcoma,
Ewing’s sarcoma,
osteomyelitis and non-specific bone-marrow edema (younger population,
Fig.
2,3,13),
and solid-tumor metastases (older patients,
Fig.
11,12).
MRI/DCE-MRI and PET-CT were used in the follow-up evaluation.
Scintigraphy was available in two cases (Fig.
1,3).
Biopsy revealed primary bone NHL in all but one patients,
who was diagnosed with primary Hodgkin’s lymphoma of the bone (Fig.
9,10).
Follow-up imaging with CT and MRI mediated the evaluation of response to treatment and in some cases designated alterations of therapy (Fig.
7,8,9-10,14).
Emphasis was put in the differential diagnosis of lymphomatous musculoskeletal lesions,
from both benign entities,
such as seronegative spondyloarthritis (Fig 5) and Paget disease of the bone (Fig.
12),
as well as from other osseous malignancies or metastatic disease.