1 ** 67/F C.C.: right pelvic pain for 3 months PMHx : thyroid
cancer OP history 1)What is your impression? 2) A first impression
and three or less differential diagnoses are acceptable. Slide 2 2
** Plain film: - an expansile, lytic lesion involving medial aspect
of right iliac wing - loss of medial cortical margin &
extension across right SI joint - no internal matrix mineralization
and no periosteal reaction Bone scan - decreased tracer uptake in
right ilium consistent with lytic lesion seen on plain film Slide 3
3 DDX : Meta vs Myeloma * Tumor uptake (-) : extremely aggressive
or purely osteolytic highly aggressive anaplastic tumors, reticulum
cell sarcoma, RCC, thyroid ca, histiocytosis, neuroblastoma, and
multiple myeloma ** Slide 4 4 ** Right iliac bone biopsy :
metastatic thyroid carcinoma Diagnosis : Thyroid cancer metastasis
Slide 5 5 Metastasis Bone scan evaluation Slide 6 6 Target Sites
Red Marrow Lumbar > Thoracic > Cervical Uncommon sites
Mandible, Patella distal to the knee and elbow Slide 7 7
Hematogeneous Route Venous > Arterial Batsons plexus Extensive
comm. Sluggish flow Reflux Slide 8 8 Primary / Metastasis Bone
expansion Periosteal reaction Soft tissue mass Multiplicity
Metastasis + +++ (10% solitary) Primary +++ + * Meta from lung
ca,Thyroid ca, RCC : solitary, expansile Slide 9 9 Typical
Radiologic Appearance of Metastases in Adults Primary site
Appearance on Plain Radiographs Appearance on Bone scan
BreastLytic,mixed or blasticIncreased isotope uptake Prostate
Blastic; occasionally mixed or lytic Increased isotope uptake Lung
Lytic mixed; occasionally blastic Increased isotope uptake
KidneyLytic, blow-out Often decreased isotope uptake Thyroid Lytic,
blow-out; sometimes normal Often decreased or normal uptake Slide
10 10 Bone scan : Application Tumor extent or localization Initial
tumor staging Identify metastatic sites Monitor disease progression
or therapy response Slide 11 11 Bone Metastasis 1. Multiple lesions
of varing intensity,size,shape 2. Irregular distribution in axial
skeleton 3. Photon deficient lesion extremely aggressive or purely
osteolytic 4. Superscan pattern 5. Solitary lesion Slide 12 12
Metastasis Uptake of tracer - dependent on blood flow and on
osteoblastic activity Malignancy hot uptake sensitive than plain
image (3-5% vs 30-50%) Cold uptake extremely aggressive or purely
osteolytic Slide 13 13 Rib metastasis vs Benign fracture Benign
Fracture Focal rather than linear Decreased uptake over 3-6mon
Aligned in same location Slide 14 14 Bone scan : Caution ! Cold
uptake Insufficiency fracture Superscan Flare phenomenon Slide 15
15 In cancer patients, - due to metastatic disease (> 80%) may
occur - aggressive or purely osteolytic tumor - disruption of blood
supply to bone - significant marrow involvement, particularly in a
vertebral body cause - highly aggressive anaplastic tumors, -
reticulum cell sarcoma, - RCC, thyroid carcinoma, - histiocytosis,
neuroblastoma, and - especially multiple myeloma ** Bone scan :
Cold uptake Slide 16 16 Cold uptake Insufficiency fracture
Superscan Flare phenomenon Bone scan : Caution ! Slide 17 17
Kyphosis Linear rib H-shaped sacral uptake Bone scan :
Insufficiency Fx Slide 18 18 Bone scan : Caution ! Cold uptake
Insufficiency fracture Superscan Flare phenomenon Slide 19 19
Superscan ? - Poorly or non-visualization of kidney - bone to
background RI ratio cause far advanced bone metastasis - prostate,
breast, lung, bladder, stomach etc metabolic condition - superscan
in both axial and peripheral skeleton - Renal osteodystrophy,
primary hyperparathyroidism myelofibrosis Bone scan : Superscan
Slide 20 20 Superscan : Metastasis Meta - superscan Normal Slide 21
21 Superscan : renal osteodystrophy Meta - superscan Metabolic -
superscan diffuse skull & mandible (+) Slide 22 22 Bone scan :
Caution ! Cold uptake Insufficiency fracture Superscan Flare
phenomenon Slide 23 23 Bone scan : Caution ! Cold uptake
Insufficiency fracture Superscan Flare phenomenon transient
increase in lesion activity secondary to healing under
antineoplastic treatment concomitant with increased sclerosis Slide
24 24 increase in uptake intensity or appearance of new lesion
within 3-6 months of staisfactory response to therapy improvement
on F/U bone scan incidence up to 20% in breast and prostate ca good
prognostic sign in breast cancer DDX : progression of metastatic
disease Bone scan : Flare phenomenon Slide 25 25 Bone scan : Flare
phenomenon Flare phenomenon < 3 month Disease progress Number
& intensity of lesions beyond 6 months 3 month6monthinitial
Slide 26 26 Bone scan vs MRI MRI : superior sensitivity Limitation
of Scintigraphy - specificity - intramedullary lesion Tumor is in
marrow space only and has not elicited a reactive response in
adjacent bone - aggressive or purely osteolytic lesion Slide 27
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