1. Lecturer of Clinical oncology department Menoufia university- Egypt
Study of Distribution of bone metastases in metastatic breast cancer patients compared to other major cancer
Presenting author:
Dr. Suzy.F. Gohar
Lecturer of Clinical oncology department
Menoufia university- Egypt

2. Introduction
Any malignant tumor can metastasize to bone. Mainly breast cancer in females and prostate cancer in males and lung cancer in both.
Bone scan is a sensitive but not specific method for evaluation of bone metastases.
However, the clinical data and the pattern of bone scan findings help the physician to narrow the diagnostic differentials.

3. Aim of the work
Evaluation of pattern of distribution of skeletal metastases in patients with breast carcinoma compared to other common cancers .
Explore if there is a specific distribution of bony deposits in breast cancer patients compared to all other major malignancies to reduce diagnostic differentials.

4. Method
Positive bone scan films were collected and studied regarding number and sites of metastatic lesions.
The involved areas were divided into nine portions: skull, sternum, spine, ribs, pelvic bones, sacrum, humeri , scapulae, femora and clavicles.
Based on number of metastatic lesions patients were divided into three categories:
few metastatic lesions (≤ 3lesions),
intermediate metastatic lesions (4-≤9 lesions)
extensive metastatic lesions (≥10 lesions).

5. Results
We collected 134 patients who were histologically proved to have malignancies and whom bone scans were positive for bone deposits.

6. Distribution of the studied patients regarding their demographic characteristics:%
Age
Mean ±SD
Range
53.88±11.98
28-90
Sex
Male
Female 85 89
33.6
66.4
Type of cancer
Breast
HCC
Prostate
Lung
Bladder
Head and neck 81 8 24 12 6 3
60.4
6.0
17.9
9.0
4.5
2.2

7. Distribution of the studied group according number of metastatic lesions (few, intermediate and extensive).
Cancer
Breast
(n=81)
HCC
(n=8)
Prostate
(n=24)
Lung
(n=12)
Bladder
(n=6)
Head and neck
(n=3) no %
Metastasis
Few
Intermediate
Extensive 37 29 15
45.7
35.8
18.5 7 1
87.5
12.5 4 8 12
16.7
33.3
50.0 3 2
58.3
25.0 6
100.0
66.7

8. Distribution of the studied group according to Frequency of involved sites
Cancer
Breast
(n=81)
HCC
(n=8)
Prostate
(n=24)
Lung
(n=12)
Bladder
(n=6)
Head and neck
(n=3) no %
Ribs 18
22.2 1
12.5 10
41.7 4
33.3
0.0
Scapula 3
3.8
8.3
Skull 7
8.6 5
 20.8
Sternum 11
13.6
Spine 68
84.0
37.5 21
87.5 9
75.0
Spine site
Cervical
Thoracic
Lumber only
Cer+Th
Th+Lumb
Cer+Th+Lumb 19 25
1.5
27.9
36.8
4.4 2
66.7 6 8
4.8
28.6
38.1
23.8
11.1
55.6
Sacrum 14
17.3

9. Cancer Breast (n=81) HCC (n=8) Prostate (n=24) Lung (n=12) Bladder
Cancer
Breast
(n=81)
HCC
(n=8)
Prostate
(n=24)
Lung
(n=12)
Bladder
(n=6)
Head and neck
(n=3) no %
Pelvis 30
37.0 4
50.0 16
66.7 3
25.0 2
33.3 1
Iliac
13.3 7
43.8
100.0
Pubic
3.3
Ischium
Hip 6
20.0
6.2
Iliac +pubic
Iliac + ischium
6.7
Iliac+ hip 9
30.0
Iliac + obturator
Hip+ ischium
12.5
Acetabulum
(Ischium+ ileum+ acetabulum+ hip)
(Ischium+ ileum+ acetabulum+ pubis)
Pubic+ acteabulum

10. Cancer
Breast
(n=81)
HCC
(n=8)
Prostate
(n=24)
Lung
(n=12)
Bladder
(n=6)
Head and neck
(n=3) no %
Humeri 13
16.0 2
25.0 7
29.2 3 4
66.7
Site humeri
Upper shaft
Lower shaft
Whole length 11
84.6
15.4 1
50.0 6
85.7
14.3
100.0
75.0
Femuri 25
30.9 10
41.7
16.7
33.3
Site femuri 20
80.0
12.0
8.0 9
90.0
10.0
Tibii
2.5
Site tibii

11. Distribution of the studied group regarding Frequency of involved sites
Cancer
Breast
(n=81)
HCC
(n=8)
Prostate
(n=24)
Lung
(n=12)
Bladder
(n=6)
Head and neck
(n=3) no %
Ribs 18
22.2 1
12.5 10
41.7 4
33.3
0.0
Scapula 3
3.8
8.3
Skull 7
8.6 5
 20.8
Sternum 11
13.6
Spine 68
84.0
37.5 21
87.5 9
75.0
Spine site
Cervical
Thoracic
Lumber only
Cer+Th
Th+Lumb
Cer+Th+Lumb 19 25
1.5
27.9
36.8
4.4 2
66.7 6 8
4.8
28.6
38.1
23.8
11.1
55.6
Sacrum 14
17.3

12. Cancer
Breast
(n=81)
HCC
(n=8)
Prostate
(n=24)
Lung
(n=12)
Bladder
(n=6)
Head and neck
(n=3) no %
Pelvis 30
37.0 4
50.0 16
66.7 3
25.0 2
33.3 1
Iliac
13.3 7
43.8
100.0
Pubic
3.3
Ischium
Hip 6
20.0
6.2
Iliac +pubic
Iliac + ischium
6.7
Iliac+ hip 9
30.0
Iliac + obturator
Hip+ ischium
12.5
Acetabulum
(Ischium+ ileum+ acetabulum+ hip)
(Ischium+ ileum+ acetabulum+ pubis)
Pubic+ acteabulum

13. Cancer
Breast
(n=81)
HCC
(n=8)
Prostate
(n=24)
Lung
(n=12)
Bladder
(n=6)
Head and neck
(n=3) no %
Humeri 13
16.0 2
25.0 7
29.2 3 4
66.7
Site humeri
Upper shaft
Lower shaft
Whole length 11
84.6
15.4 1
50.0 6
85.7
14.3
100.0
75.0
Femuri 25
30.9 10
41.7
16.7
33.3
Site femuri 20
80.0
12.0
8.0 9
90.0
10.0
Tibii
2.5
Site tibii

14. Comparison between breast cancer patients and other malignancies regarding number and site of involved sites.
Cancer χ2
Test P-
value
Breast
(N=81)
Others
(N=53) No %
Origin
Primary
Secondary 46 35
56.8
43.2
15.34
<0.001
Number of Metastasis
Few
Intermediate
Extensive 37 29 15
45.7
35.8
18.5 26 11 16
49.1
20.8
30.2
4.39
0.111
Ribs 18
22.2
1.07
0.300
Scapula 3
3.8 1
1.9
0.35
0.550
Skull 7
8.6 5
9.4
0.02
0.875
Sternum
13.6
*5.37
0.028(S)
Spine 68
84.0 33
62.3
8.11
0.004(S)
Spine site
Cervical
Thoracic
Lumber
Cer+Th
Th+Lum
Cer+Th+Lumb 19 25
1.5
27.9
36.8
4.4 6
3.0
18.2
21.2
33.3 Z
0.25
0.81
1.35
0.33
2.30
0.800
0.415
0.176
0.745
0.021(S)

15. Cancer χ2
Test P-
value
Breast
(N=81)
Others
(N=53) No %
Pelvis 30
37.0 26
49.1
1.90
0.168
Iliac
Pubic
Ischium
Hip
Iliac +pubic
Iliac + ischium
Iliac+ hip
Iliac + obturator
Hip+ ischium
Acetabulum
(Ischium+ ileum+ acetabulum+ hip)
(Ischium+ ileum+ acetabulum+ pubis)
Pubic+ acteabulum 4 1 6 2 9
13.3
3.3
20.0
6.7
30.0
0.0 10 3
38.5
3.8
7.7
11.5 Z
3.17
0.33
2.44
1.70
3.51
0.70
2.02
1.52
0.73
1.04
0.001(S)
0.473
0.014(S)
0.089
0.743
0.740
0.0004(S)
0.481
0.043(S)
0.128
0.462
0.297

16. conclusion
In breast cancer patients, spine especially (lumbar region) is the most frequent site of involvement followed by pelvic bones and then axial skeleton(especially upper third of femur).
Compared to other malignancies Spine , sternal and iliac bone involvement were significantly more frequent in breast cancer patients.