Bone Tumor Diagnosis,Another view

When we are confronted with a plain film of a bone , we must think about 6 points to narrow the differential diagnosis of the case.

This six clues are as follow:

1-The first clue is to define the pattern of the bone destruction you see,if it is

a-Geographical or

b-Moth eaten or

c-Permeative.

Examples:

a-geographical lesions such as non-ossifying fibroma and esinophilic granuloma.

b-Moth eaten appearance such as

1-myeloma.

2-metastases.

3-lymphoma.

4-ewings sarcoma.

c-Permeative lesion such as Round-cell lesions .

1-Myeloma.

2-Metastases.

3-Lymphoma.

4-Ewing's Sarcoma

5-Leukaemia

6- Neuroblastoma

7-Osteomyelitis

2-The second clue is the location of the lesion,if it is

- In the transverse plane:
a) Central - Enchondroma
b) Eccentric -GCT, osteosarcoma, chondromyxoid fibroma
c) Cortical - Non-ossifying fibroma, osteoid osteoma
d) Parosteal - Parosteal osteosarcoma, osteochondroma
-In the longitudinal plane:
a) Epiphyseal - GCT, chondroblastoma
b) Metaphyseal - Osteomyelitis, osteosarcoma
c) Diaphyseal - Round cell lesions, ABC, enchondroma

3-The third clue is concerning with the type of periosteal reaction, is it unilamelated ( benign) ,multilamelated,perpendicular or with codemen triangle(malignant).

4-Clues by matrix of the lesion,which could be as follow:

a- Ossification (Osteoblastic process) - Well organized ossified mass with fluffy, cotton-like or cloud-like densities. Eg. Osteosarcoma.

b-Calcification (Cartilaginous process)- Unorganized calcified matrix which is comma-shaped, punctate, annular or popcorn-like. Eg. Enchondroma, Chondrosarcoma, Chondromyxoid fibroma.

5-Clues By Density Of Lesion

1. Sclerotic Cortical lesions- Osteoid osteoma- Brodie's abscess- Stress fracture
2. Lytic lesions in children- Eosinophilic granuloma- Neuroblastoma- Leukemia
3. Lytic lesions in adult- Metastatic lesions (Lung, Kidney, Thyroid)- Multiple myeloma- Primary bone tumor
4. Blastic lesion in children- Medulloblastoma- Lymphoma
5. Blastic lesion in adult- Metastatic disease (Breast, Prostate)- Lymphoma- Paget's disease

6. Clues by number of lesion Multiple lesion: More often benignMalignancies with multiple lesions- Metastatic disease- Multiple myeloma- Lymphoma

Summary:

Let us look at the following:

location, pattern,matrix and the density of the lesion,in addition to type of peri-osteal reaction and number of lesions.