Demographics:
A total of 553 patients were included; 12 (2.2%) were males. The mean age ± SD (71± 5.1), and the median is 70 (7.2) years. However, only 121 (21.9%) were 75 years or older and 40 (7.2%) were ≥ 80 years old. Family history of breast cancer in first degree relatives was identified among 115 (20.8%); 18 (15.7%) of them with an additional cancer other than breast.
Clinicopathologic Features:
Invasive ductal carcinoma (IDC) was the predominant pathology identified among 460 (83.2%) while invasive lobular carcinoma (ILC) was seen among 60 (10.8%). On presentation, 114 (20.6%) patients had metastatic disease and was mostly visceral (81; 71.1%). Patients with non-metastatic disease had poor pathological features including node-positive in 244 (55.6%), grade-III in 170 (38.7%) and lymphovascular invasion in 173 (39.4%). Among the 501 patients with known HER-2 status, 92 (18.4%) were positive and 38 (7.6%) had triple-negative disease. Larger tumors with T3 and T4 disease were seen in 48 (10.9%) and 13 (3.0%), respectively,Table-1.
Table-1: Patients characteristics, (n= 553)
Characteristics
|
Number of patients
|
Percentage
|
Gender
|
Female
|
541
|
97.8%
|
|
Male
|
12
|
2.2%
|
Age group (years)
|
65-69
|
270
|
48.8%
|
|
70-74
|
162
|
29.3%
|
|
75-79
|
81
|
14.6%
|
|
≥ 80
|
40
|
7.2%
|
Histology
|
IDC
|
460
|
83.2%
|
|
ILC
|
60
|
10.8%
|
|
Others#
|
33
|
6.0%
|
Tumor Size (T)*
|
Tis
T1
|
2
114
|
0.23%
26.0%
|
|
T2
|
229
|
52.2%
|
|
T3
|
48
|
10.9%
|
|
T4
|
13
|
3.0%
|
|
Tx
|
35
|
7.5%
|
Axillary nodal metastasis*
|
Negative
|
178
|
40.5%
|
|
Positive
|
244
|
55.6%
|
|
Unknown
|
17
|
3.9%
|
Stage
|
I
|
74
|
13.4%
|
|
II
|
109
|
19.7%
|
|
III
|
241
|
43.6%
|
|
IV
|
114
|
20.6%
|
|
NA
|
15
|
2.7%
|
Grade*
|
I
|
38
|
8.7%
|
|
II
|
226
|
51.5%
|
|
III
|
170
|
38.7%
|
|
NA
|
5
|
1.1%
|
Lymphovascular invasion (LVI)*
|
Unidentified Negative
Identified Unknown
|
204
173
62
|
47.0%
39.4%
14.1%
|
Progesterone Receptors (PR)
|
Negative
Positive
Unknown
|
104
441
8
|
18.8%
79.7%
1.4%
|
Estrogen Receptors (ER)
|
Negative
Positive
Unknown
|
87
458
8
|
15.7%
82.8%
1.4%
|
HER2-neu^
|
Negative
Positive
Unknown
|
409
92
52
|
81.6%
18.4%
9.4%
|
NA: Not available; *For M0 patients n=439; ^ From the 501 patients tested for HER2
# Include: Papillary, Medullary and Metaplastic
Among the patients with non-metastatic disease, modified radical mastectomy was the most performed surgery (274; 62.4%) while 125 (28.5%) patients had breast conserving surgery (BCS). Additionally, 29 (6.6%) never had surgery mostly because of patients’ refusal (n=5), comorbidities or poor performance status (n=20). Sentinel lymph node biopsy (sLN) was performed on 156 (38.0%) while axillary dissection; upfront or following a positive sLN, was performed on 285 (69.5 %%). Breast reconstruction, both immediate and delayed, was performed on only 20 (4.9%) of the patients, Figure-1.
Among patients with non-metastatic disease, 279 (63.6%) were treated with chemotherapy; 67 (24.0%) were in the neoadjuvant setting. However, 144 (32.8%) had no chemotherapy because of low-risk disease, patient refusal or poor performance status. Similarly, chemotherapy was offered for only 16 (14.0%) patients with metastatic disease. All patients, with hormone-receptor positive tumors, were treated with aromatase inhibitors.
Survival:
After a median follow up of 45 (range: 0.23-154) months, 5-year overall survival for the whole group was 67.6% while the median overall survival was 104.2 months. Survival was significantly better for patients with non-metastatic disease with 5-year OS of 78.8% compared to 25.4% for patients with metastatic disease; P<0.0001 (Figure-2).
Among the patients with non-metastatic disease, survival was significantly better for patients with node-negative compared to those with node-positive disease; 5-year OS was 85.4% and 74.1%, respectively, P=0.002 (Figure-3a). Survival advantage was also noted among patients with no lymphovascular invasion (LVI) and those with low-grade disease as illustrated in Figure-3b and Figure-3c, respectively.
On Cox regression, only positive lymph nodes were associated with poor outcome in patients with non-metastatic disease (Hazard Ratio [HR], 1.75; 95% CI: 1.006-3.034, P=0.048). Tumor grade (grade-III versus grade I and II) and LVI were not significant, Table-2.
Table-2: Cox Regression for patients with nonmetastatic disease (n=370)
Parameter
|
p-value
|
Hazard Ratio
|
95% Hazard Ratio Confidence Limits
|
Nodal metastasis
|
Positive vs. Negative
|
0.0476
|
1.747
|
1.006
|
3.034
|
Triple-Negative
|
Yes vs. No
|
0.1901
|
1.696
|
0.770
|
3.735
|
Grade
|
III vs. I+II
|
0.1595
|
1.407
|
0.874
|
2.264
|
Lymphovascular invasion (LVI)
|
Identified vs. Unidentified
|
0.3123
|
1.298
|
0.783
|
2.153
|