SURVIVAL OF NODE-NEGATIVE BREAST CANCER PATIENTS TREATED AT  
THE UNIVERSITY MEDICAL CENTRE MARIBOR IN THE PERIOD 2000–2009
Nina FOKTER DOVNIK1*, Darja ARKO2, Nina ČAS SIKOŠEK2, Iztok TAKAČ2,3
1University Medical Centre Maribor, Department of Oncology, Ljubljanska 5, 2000 Maribor, Slovenia
2University Medical Centre Maribor, University Clinical Department of Gynaecology and Perinatology, 
Ljubljanska 5, 2000 Maribor, Slovenia
3University of Maribor, Faculty of Medicine, Taborska 8, 2000 Maribor, Slovenia
Received: May 21, 2016
Accepted: Apr 21, 2017
Original scientific article
Introduction. Breast cancer is increasingly diagnosed in the early stages without regional nodal involvement. The aim 
of the present study was to determine the 5-year overall (OS) and breast cancer specific survival (BCSS) for patients 
with node-negative breast cancer treated at the University Medical Centre Maribor, and compare it with survival at 
the national level.
Methods. Medical records were searched for information on patients with lymph node-negative invasive breast cancer 
who received primary treatment at the University Medical Centre Maribor in the period 2000–2009. Information on all 
Slovenian node-negative breast cancer patients diagnosed in the same period was obtained from the Cancer Registry 
of Republic of Slovenia. Time trends in survival were assessed by comparing the periods 2000–2004 and 2005–2009.
Results. The 5-year OS and BCSS of patients treated in Maribor in the period 2000–2009 were 92.3% (95% CI, 90.5%–
94.1%) and 96.4% (95% CI, 95.2%–97.6%), respectively, and did not differ from the corresponding OS and BCSS for 
Slovenian patients. Although the improvement in OS for patients from Maribor diagnosed in the period 2005–2009 
compared to 2000–2004 did not reach statistical significance (HR 0.73; 95% CI, 0.51–1.05; p=0.086), BCSS significantly 
improved over the same time periods (HR 0.53; 95% CI, 0.30–0.94; p=0.028).
Conclusions. Survival of node-negative breast cancer patients treated at the University Medical Centre Maribor is 
comparable to survival of corresponding patients at the national level. The rising number of long-term breast cancer 
survivors places additional importance on survivorship care.
Uvod. Raka dojk vse pogosteje odkrijemo v zgodnjih stadijih, ko regionalne bezgavke še niso prizadete. Namen te 
raziskave je bil ugotoviti petletno celokupno in specifično preživetje bolnic z rakom dojk brez zasevkov v bezgavkah, 
zdravljenih v Univerzitetnem kliničnem centru Maribor, in ga primerjati s preživetjem na ravni Slovenije.
Metode. Podatke o bolnicah z invazivnim rakom dojk brez zasevkov v bezgavkah, ki so bile primarno zdravljene v 
Univerzitetnem kliničnem centru Maribor v obdobju 2000–2009, smo pridobili iz medicinske dokumentacije. Podatke 
o vseh slovenskih bolnicah z invazivnim rakom dojk brez zasevkov v bezgavkah, odkritim v istem obdobju, smo 
pridobili iz Registra raka Republike Slovenije. Za analizo časovnih vzorcev preživetja smo primerjali dve petletni 
obdobji odkritja bolezni: 2000–2004 in 2005–2009.
Rezultati. Petletno celokupno preživetje bolnic, zdravljenih v Univerzitetnem kliničnem centru Maribor v letih 
2000–2009, je znašalo 92,3 % (95-odstotni interval zaupanja 90,5–94,1 %), specifično preživetje pa 96,4 % (95-odstotni 
interval zaupanja 95,2–97,6 %). Preživetje bolnic, zdravljenih v Univerzitetnem kliničnem centru Maribor, se ni 
pomembno razlikovalo od ustreznih preživetij vseh slovenskih bolnic. Opazno je bilo izboljšanje celokupnega 
preživetja pri bolnicah, primarno zdravljenih v obdobju 2005–2009, v primerjavi s tistimi, zdravljenimi v obdobju 
2000–2004, čeprav pri bolnicah, zdravljenih v Univerzitetnem kliničnem centru Maribor, ta trend ni dosegel statistične 
značilnosti (Maribor: razmerje tveganj 0,73; 95-odstotni interval zaupanja 0,51–1,05; p=0,086; Slovenija: razmerje 
tveganj 0,77; 95-odstotni interval zaupanja 0,66–0,89; p<0,001). Izboljšanje specifičnega preživetja v istih obdobjih 
diagnoze je bilo statistično značilno pri obeh skupinah bolnic (Maribor: razmerje tveganj 0,53; 95-odstotni interval 
zaupanja 0,30–0,94; p=0,028; Slovenija: razmerje tveganj 0,66; 95-odstotni interval zaupanja 0,54–0,81; p<0,001).
Zaključki. Preživetje bolnic z rakom dojk brez zasevkov v bezgavkah, zdravljenih v Univerzitetnem kliničnem centru 
Maribor, je primerljivo s preživetjem vseh podobnih bolnic v Sloveniji. Zaradi vse večjega števila žensk z dolgotrajnim 
preživetjem po zdravljenju raka dojk, pri katerih se pojavljajo specifične zdravstvene težave in tveganja, postaja 
vse pomembnejša njihova celostna in dolgoročna obravnava.
ABSTRACT
Keywords: 
breast cancer, 
survival, 
time trends, 
regional 
differences, 
Slovenia
IZVLEČEK
Ključne besede: 
rak dojk, 
preživetje, 
časovni vzorci, 
regionalne 
razlike, 
Slovenija
*Corresponding author: Tel: ++ 386 2 321 1905; E-mail: nfokter@gmail.com
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185
PREŽIVETJE BOLNIC Z RAKOM DOJK BREZ ZASEVKOV V BEZGAVKAH, 
ZDRAVLJENIH V UNIVERZITETNEM KLINIČNEM CENTRU MARIBOR 
V OBDOBJU OD LETA 2000 DO LETA 2009
Fokter Dovnik N, Arko D, Čas Sikošek N, Takač I. Survival of node-negative breast cancer patients treated in the University Medical Centre Maribor in the period 
2000–2009. Zdr Varst 2017; 56(3): 185-192.
© Nacionalni inštitut za javno zdravje, Slovenija. 
1 INTRODUCTION
Breast cancer is the most common cancer in women whose 
incidence continues to grow in most parts of the world, 
largely due to the aging population. In Slovenia, crude 
breast cancer incidence has increased from 94.3/100.000 
women in 2000 to 110.7/100.000 women in 2009 (1). 
Breast cancer remains the leading cause of cancer-related 
death in Slovenia (2) as well as in Europe (3) despite the 
remarkable improvements in survival achieved over the 
last decades (2, 4, 5). Breast cancer screening programmes 
have been implemented in many countries across Europe 
since the 1990s (6). These have been shown to improve 
breast cancer specific survival rates by approximately 
20%, mostly due to earlier diagnosis (7-9). In Slovenia, 
national breast cancer screening programme DORA has 
begun with biannual organised screening of women 
aged 50–69 in the Ljubljana region in 2008 and has been 
gradually expanding so that it now includes 72% of the 
target population in Slovenia (10). A slight shift towards 
earlier diagnosis has been already noted in Slovenia before 
widespread organised breast cancer screening (11, 12), 
probably due to a considerable amount of “opportunistic” 
mammography testing and rising public awareness. In 
2013, 55.5% of breast cancers in Slovenian women were 
diagnosed in a localised stage without regional nodal 
involvement (2). This number is expected to rise further 
in the following years.
Irrespective of such a large proportion of patients with 
localised disease, Slovenian data on survival of this 
prognostically favourable group of patients are scarce. 
In addition, separate survival data for patients treated 
at the University Medical Centre Maribor, a combined 
secondary/tertiary care centre treating breast cancer 
patients from the north-eastern region of Slovenia, have 
never been published. We performed this retrospective 
study to determine the 5-year overall and breast cancer 
specific survival for patients with node-negative breast 
cancer who received primary treatment at the University 
Medical Centre Maribor in the period 2000–2009. As 
a quality control measure, we compared the survival 
of our patients with that of patients with the same 
characteristics at the national level.
2 METHODS
Medical records were searched for information on patients 
with lymph node-negative invasive breast cancer without 
distant metastases who received primary treatment at 
the University Medical Centre Maribor, Slovenia, between 
January 1 2000 and December 31 2009. Exclusion criteria 
were systemic treatment or radiotherapy before primary 
surgery and more than one primary cancer. Information 
on date of diagnosis, patient age, primary treatment, 
possible disease recurrence, date and cause of death was 
obtained from hospital medical records. Information on 
possible date and cause of death for the patients who did 
not regularly attend follow-up visits was obtained from 
the Cancer Registry of Republic of Slovenia. The cause 
of death for these patients was double-checked with 
their family physicians. All patients were followed for a 
minimum of 5 years until December 31, 2014. 
The study group was compared with all female permanent 
residents of Slovenia who were diagnosed with invasive 
breast cancer without lymph node or distant metastases 
in the period 2000–2009 who were primarily treated 
with surgery and did not receive preoperative systemic 
treatment or radiotherapy. All data for this group of 
patients were obtained from the Cancer Registry of 
Republic of Slovenia (1). In order to make this group as 
similar to the study group as possible and because the 
Cancer Registry did not yet have information on cause of 
death for patients who died in 2015 and 2016, December 
31, 2014, was chosen as the cut-off date for survival 
analyses for these patients, as well. 
All patients received either lumpectomy with sentinel 
lymph node biopsy followed by radiotherapy or modified 
radical mastectomy as locoregional treatment. Adjuvant 
systemic therapy was given according to the relevant 
clinical practice guidelines and the decision made by 
the multidisciplinary tumour board. In general, all 
patients with hormone receptor positive tumours were 
offered adjuvant hormone therapy, and most patients 
with hormone receptor negative tumours were offered 
adjuvant chemotherapy. Adjuvant chemotherapy in 
addition to adjuvant hormone therapy was offered to high-
risk patients with hormone receptor positive tumours. 
Adjuvant trastuzumab in combination with chemotherapy 
was offered to most patients with HER2 positive tumours 
treated in the period 2005–2009 and to a few selected 
high-risk patients in the period 2000–2004.
To analyse the time trends in survival, patients were 
divided in two groups based on the year of diagnosis: 
2000–2004 and 2005–2009. Overall survival (OS) was 
calculated from the date of diagnosis until the date of 
death from any cause. Breast cancer specific survival 
(BCSS) was calculated from the date of diagnosis until the 
date of death from breast cancer. Kaplan-Meier method 
was used to calculate survival curves and univariate Cox 
regression was used to assess the hazard ratios (HR). 
To control for some other clinically important variables 
apart from treatment period, multivariate analyses were 
performed by applying the multivariate Cox proportional 
hazards model. All tests were performed at a significance 
level of p=0.05 and a confidence interval (CI) of 95%. All p 
values were two-sided. Statistical analysis was performed 
using the SPSS software package v. 22 (IBM, Armonk, NY, 
USA).
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3 RESULTS
In the period 2000–2009, 858 node-negative invasive breast 
cancer patients without distant metastases were treated 
at the University Medical Centre Maribor. This represented 
18.1% of the 4740 corresponding node-negative patients 
who were treated in Slovenia in the same period. The 
characteristics of patients in both groups are shown in 
Table 1. 
Table 1.
Figure 1.
Figure 2.
Characteristics of node-negative breast cancer 
patients treated at the University Medical Centre 
Maribor (N=858) and in Slovenia (N=4740) in the 
period 2000–2009.
Kaplan-Meier plot of overall survival (OS) probability 
for node-negative breast cancer patients treated 
at the University Medical Centre Maribor, according 
to the period of diagnosis (N=858). The difference 
in OS between the two periods of diagnosis is not 
statistically signifi cant (p=0.086).
Kaplan-Meier plot of overall survival (OS) probability 
for all Slovenian node-negative breast cancer 
patients according to the period of diagnosis 
(N=4740). OS was signifi cantly better for patients 
diagnosed in the period 2005–2009, compared to 
those diagnosed in the period 2000–2004 (p<0.001).
Time period
  2000–2004
  2005–2009
Age
  <40 years
  ≥40 and <70 years
  ≥70 years
Postoperative radiation therapy
  no
  yes
Adjuvant systemic therapy
  no
  yes
2253 (47.5)
2487 (52.5)
208 (4.4)
3316 (70.0)
1216 (25.6)
2504 (52.8)
2236 (47.2)
839 (17.7)
3901 (82.3)
373 (43.5)
485 (56.5)
37 (4.3)
561 (65.4)
260 (30.3)
439 (51.2)
419 (48.8)
71 (8.3)
787 (91.7)
Slovenia
N (%)
Maribor
N (%)
Overall survival analysis was based on 163 events in the 
group of patients treated in Maribor, and 943 events in all 
Slovenian patients. The 5- and 10-year OS probabilities 
of patients who underwent primary treatment at the 
University Medical Centre Maribor in the period 2000–2009 
were 92.3% (95% CI, 90.5%–94.1%; 66 events, 44 censored 
cases) and 80.1% (95% CI, 77.0%–83.2%; 133 events, 479 
censored cases), respectively.The 5-year OS probabilities 
of the patients diagnosed in the periods 2000–2004 and 
2005–2009 were 89.2% (95% CI, 86.1%–92.3%) and 94.6% 
(95% CI, 92.6%–96.6%), respectively (HR 0.73; 95% CI, 
0.51–1.05; p=0.086; Figure 1). In the group of all Slovenian 
patients, the 5- and 10-year OS probabilities of patients 
diagnosed in the period 2000–2009 were 91.3% (95% CI, 
90.5%–92.1%; 413 events, no censored cases) and 79.6% 
(95% CI, 78.2%–81.0%; 809 events, 2179 censored cases), 
respectively. For these patients, OS was signifi cantly 
better for patients diagnosed in the period 2005–2009, 
compared to those diagnosed in the period 2000–2004 (HR 
0.77; 95% CI, 0.66–0.89; p<0.001; Figure 2).
A comparison of 1-, 3- and 5-year OS probabilities 
according to the period of diagnosis and site of treatment 
is presented in Table 2. No difference in overall survival 
was observed between the patients treated at the 
University Medical Centre Maribor and all Slovenian 
patients (HR 1.07; 95% CI, 0.91–1.27; p=0.413; Figure 3).
Breast cancer specifi c survival analysis was based on 65 
events in the group of patients treated in Maribor, and 
458 events in all Slovenian patients. The 5- and 10-year 
BCSS probabilities of patients who underwent primary 
treatment at the University Medical Centre Maribor in 
the period 2000–2009 were 96.4% (95% CI, 95.2%–97.6%; 
30 events, 69 censored cases) and 91.1% (95% CI, 88.7%–
93.4%; 57 events, 556 censored cases), respectively. The 
corresponding 5- and 10-year BCSS probabilities in all 
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188
Table 2. Comparison of 1-, 3- and 5-year overall survival (OS) probabilities for node-negative breast cancer patients treated at the 
University Medical Centre Maribor (N=858) and in Slovenia (N=4740) in the period 2000–2009. The only statistically signifi cant 
OS difference was observed between the two periods in Slovenian patients (p<0.001).
1-year
3-year
5-year
98.7
94.3
89.2
98.9
95.2
90.1
99.4
96.7
94.6
99.0
95.5
92.4
97.5–99.9
91.9–96.7
86.1–92.3
98.5–99.3
94.2–96.2
88.9–91.3
98.6–100
95.1–98.3
92.6–96.6
98.6–99.4
94.7–96.3
91.4–93.4
Maribor Slovenia
2000-2004
% % % %95% CI 95% CI 95% CI 95% CI
2005-2009 2000-2004 2005-2009
OS
Figure 3. Figure 4.Kaplan-Meier plot of overall survival (OS) probability 
for node-negative breast cancer patients treated 
at the University Medical Centre Maribor (N=858), 
compared to all Slovenian node-negative breast 
cancer patients (N=4740) diagnosed in the period 
2000–2009. No difference in OS was observed 
(p=0.413). The fi nal part of the line representing the 
Maribor data is less reliable, because of the small 
number of patients at risk.
Kaplan-Meier plot of breast cancer specifi c survival 
(BCSS) probability for node-negative breast cancer 
patients treated at the University Medical Centre 
Maribor, according to the period of diagnosis 
(N=858). BCSS was signifi cantly better for patients 
diagnosed in the period 2005–2009, compared to 
the patients diagnosed in the period 2000–2004 
(p=0.028).
Slovenian patients were 95.1% (95% CI, 94.5%–95.7%; 413 
events, 183 censored cases) and 89.5% (95% CI, 88.5%–
90.5%; 415 events, 2573 censored cases), respectively.
Improved BCSS was noted in patients diagnosed in the 
period 2005–2009, compared to the period 2000–2004 for 
patients treated in Maribor (HR 0.53; 95% CI, 0.30–0.94; 
p=0.028; Figure 4), as well as for all Slovenian patients 
(HR 0.66; 95% CI, 0.54–0.81; p<0.001; Figure 5).
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189
Table 3. Comparison of 1-, 3- and 5-year breast cancer specifi c survival (BCSS) probabilities for node-negative breast cancer patients 
treated at the University Medical Centre Maribor (N=858) and in Slovenia (N=4740) in the period 2000–2009. Statistically 
signifi cant BCSS differences were observed between the two periods in patients treated in Maribor (p=0.028) and in all 
Slovenian patients (p<0.001). No differences were observed according to the site of treatment (p=0.233).
1-year
3-year
5-year
99.5
97.5
95.3
99.4
97.3
94.5
100
98.3
97.3
99.4
97.3
95.6
98.7–100
95.9–99.1
93.1–97.4
99.0–99.8
96.7–97.9
93.5–95.5
99.6–100
97.1–99.5
95.9–98.7
99.0–99.8
96.7–97.9
94.8–96.4
Maribor Slovenia
2000-2004
% % % %95% CI 95% CI 95% CI 95% CI
2005-2009 2000-2004 2005-2009
BCSS
Figure 5. Figure 6.Kaplan-Meier plot of breast cancer specifi c survival 
(BCSS) probability for all Slovenian node-negative 
breast cancer patients according to the period of 
diagnosis (N=4740). BCSS was signifi cantly better 
for patients diagnosed in the period 2005–2009, 
compared to those diagnosed in the period 2000–
2004 (p<0.001).
Kaplan-Meier plot of breast cancer specifi c survival 
(BCSS) probability for node-negative breast cancer 
patients treated at the University Medical Centre 
Maribor (N=858), compared to all Slovenian node-
negative breast cancer patients (N=4740) diagnosed 
in the period 2000–2009. No difference in BCSS was 
observed (p=0.233).
No difference in breast cancer specifi c survival was 
observed between the patients treated at the University 
Medical Centre Maribor and all Slovenian patients (HR 
0.85; 95% CI, 0.66–1.11; p=0.233; Figure 6). Table 3 shows 
a comparison of 1-, 3- and 5-year BCSS probabilities 
according to the period of diagnosis and site of treatment. 
The results of multivariate analyses of OS and BCSS are 
presented in Tables 4 and 5.
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190
Table 4.
Table 5.
Multivariate analysis of factors influencing overall survival (OS) and breast cancer specific survival (BCSS) in node-negative 
breast cancer patients treated at the University Medical Centre Maribor in the period 2000–2009 (N=858). 
Multivariate analysis of factors influencing overall survival (OS) and breast cancer specific survival (BCSS) in node-negative 
breast cancer patients treated in Slovenia in the period 2000–2009 (N=4740). 
Treatment period
(2005–2009 vs. 2000–2004)
Adjuvant radiotherapy
(yes vs. no)
Adjuvant chemotherapy
(yes vs. no)
Age
<40 years vs. ≥70 years
40–70 years vs. ≥70 years
Treatment period
(2005–2009 vs. 2000–2004)
Adjuvant radiotherapy
(yes vs. no)
Adjuvant chemotherapy
(yes vs. no)
Age
<40 years vs. ≥70 years
40–70 years vs. ≥70 years
0.63 (0.44–0.90)
0.36 (0.22–0.57)
0.56 (0.36–0.85)
0.55 (0.22–1.42)
0.33 (0.23–0.49)
0.76 (0.66–0.88)
0.60 (0.51–0.71)
0.75 (0.65–0.87)
0.37 (0.26–0.54)
0.30 (0.26–0.34)
0.51 (0.29–0.91)
0.41 (0.22–0.76)
0.39 (0.20–0.78)
2.17 (0.77–6.13)
0.80 (0.45–1.42)
0.67 (0.55–0.82)
0.65 (0.52–0.81)
0.77 (0.62–0.96)
0.86 (0.57–1.30)
0.47 (0.38–0.58)
0.011
<0.001
0.007
<0.001
  0.217
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
0.021
0.005
0.007
0.105
0.142
0.442
<0.001
<0.001
0.019
<0.001
0.475
<0.001
OS
OS
BCSS
BCSS
HR (95% CI)
HR (95% CI)
HR (95% CI)
HR (95% CI)
p
p
p
p
Factor
Factor
4 DISCUSSION
Despite some limitations as pertains the comparability of 
the groups due to the differences in data collection, we 
believe that our results show clearly enough that overall 
and breast cancer specific survival of early stage breast 
cancer patients treated at the University Medical Centre 
Maribor do not differ from the survival of all Slovenian 
patients with similar characteristics. This expected result 
serves as important evidence that the quality of treatment 
of early breast cancer patients in our centre is not inferior 
to Slovenian average. Of course, this result will also 
encourage us to try to further improve our patient care.
Improvement of survival was noted over two five-
year periods of diagnosis, 2000–2004 and 2005–2009. In 
multivariate analyses, controlling for other clinically 
important variables, statistically significant improvement 
of both OS and BCSS persisted, irrespective of patient 
age and adjuvant treatment. One of the reasons for this 
improvement is probably the increasing proportion of 
small nonpalpable tumours detected by screening. The 
other major reason for improved survival is undoubtedly 
the improvement of both adjuvant systemic treatment 
and treatment of metastatic breast cancer, as exemplified 
by the use of trastuzumab in HER2-positive disease (13).
In general, a marked improvement of 5-year relative 
survival rates of all breast cancer patients has been noted 
in most of the European countries in the first decade 
of the 21st century (14). In Slovenia, 5-year relative 
survival for breast cancer patients has risen from 81.8% 
for those diagnosed in the period 2000–2004 to 88.1% in 
the period 2005–2009 (15). However, some data suggest 
that the larger part of survival improvement in developed 
countries has been seen in higher-stage, node-positive 
disease, while little or no improvement has been noted 
in the prognostically more favourable group of node-
10.1515/sjph-2017-0025 Zdr Varst 2017; 56(3): 185-192
191
negative patients (16). In contrast, strong improvement 
of survival rates over time has been observed in node-
negative breast cancer patients in some less developed 
countries, for example, in Malaysia, where an increase of 
5-year overall survival probability from 79% in the period 
1993–1997 to 94% in 1998–2002 has been reported in a 
single-institution study (17).
The other factors associated with better survival in 
multivariate analyses of both the Maribor and the Slovenian 
cohort were adjuvant radiotherapy and adjuvant systemic 
therapy. These findings are consistent with large reviews 
of the literature (18, 19). However, firm conclusions 
about the effects of adjuvant treatment cannot be 
drawn based on our study, because we did not have exact 
information on important confounding prognostic factors 
that influence adjuvant treatment decisions. Additionally, 
age was a significant factor in our multivariate analyses as 
well. Expectedly, patients aged 70 and above were at an 
increased risk of dying of any cause, compared to younger 
patients. In the larger Slovenian cohort, these patients 
also had worse BCSS, compared to patients aged 40–70 
years, but no worse than patients under 40. Similar trends 
have been reported in other countries (20).
The results of our study confirm excellent 5-year survival 
rates in breast cancer patients without lymph node 
metastases throughout the study period. BCSS of patients 
treated at the University Medical Centre Maribor in the 
period 2000–2009 was 96.4%, and the corresponding 
BCSS of all Slovenian patients was 95.1%. These numbers 
are similar to the reported 96.9% 5-year cause-specific 
survival of node-negative breast cancer patients treated 
in Sweden in the period 2000–2004 (21). A CONCORD 
high-resolution study that compared breast cancer 
survival data across seven US states and twelve European 
countries, including Slovenia, reported 92–98% 5-year age-
standardised net survival of node-negative patients with 
small (T1) tumours, and 84–93% 5-year age-standardised 
net survival of node-negative patients with larger (T2-3) 
tumours for patients diagnosed in the period 1994–1999 
(22). 
Due to these high and further rising survival rates, it 
is essential to emphasise the need for coordinated 
survivorship care. Patients may face long-term medical 
issues, such as cardiac issues, bone health problems, 
lymphedema and thromboembolic events as a consequence 
of their disease or its treatment. In addition to follow-
up for breast cancer recurrence, it is important to keep 
in mind that these patients are at an increased risk for 
second primary malignancies. Furthermore, survivorship 
care should routinely incorporate advice on a healthy diet 
and an active lifestyle (23).
5 CONCLUSIONS
We have shown that overall and breast cancer specific 
survival of node-negative breast cancer patients treated 
at the University Medical Centre Maribor are not inferior 
to survival of patients treated elsewhere in Slovenia. 
Although survival rates of these patients who now 
constitute more than half of all Slovenian breast cancer 
patients are already very high, there was still a clear 
trend of improvement over two time periods, both in 
Maribor and in Slovenia. The rising number of long-term 
breast cancer survivors places an additional importance 
on survivorship care.
ACKNOWLEDGEMENTS
The authors would like to thank Tina Žagar, PhD, from the 
Cancer Registry of Republic of Slovenia, for providing the 
cancer registry data.
CONFLICTS OF INTEREST
The authors declare that no conflicts of interest exist.
FUNDING
No funding has been received for the conduct of this study 
and/or preparation of this manuscript.
ETHICAL APPROVAL
Received from the Republic of Slovenia National Medical 
Ethics Committee, approval No. 55/11/13.
REFERENCES
1. Zadnik V, Primic Žakelj M. SLORA: Slovenija in rak. Epidemiologija 
in register raka. Onkološki inštitut Ljubljana. Available Mar 25, 2017 
from: www.slora.si.
2. Cancer in Slovenia 2013. Ljubljana: Institute of Oncology Ljubljana, 
Epidemiology and Cancer Registry, Cancer Registry of Republic of 
Slovenia, 2016.
3. Ferlay J, Steliarova-Foucher E, Lortet-Tieulent J, Rosso S, Coebergh 
JW, Comber H et al. Cancer incidence and mortality patterns in 
Europe: estimates for 40 countries in 2012. Eur J Cancer 2013; 49: 
1374-403.
4. Amaro J, Severo M, Vilela S, Fonseca S, Fontes F, La Vecchia C et al. 
Patterns of breast cancer mortality trends in Europe. Breast 2013; 
22: 244-53.
5. Zadnik V, Žagar T, Žakelj MP. Cancer patients’ survival: standard 
calculation methods and some considerations regarding their 
interpretation. Zdr Varst 2016; 55: 134-41.
6. Altobelli E, Lattanzi A. Breast cancer in European Union: an update 
of screening programmes as of March 2014 (review). Int J Oncol 2014; 
45: 1785-92.
10.1515/sjph-2017-0025 Zdr Varst 2017; 56(3): 185-192
192
7. Independent UK Panel on Breast Cancer Screening. The benefits and 
harms of breast cancer screening: an independent review. Lancet 
2012; 380: 1778-86.
8. Myers ER, Moorman P, Gierisch JM, Havrilesky LJ, Grimm LJ, Ghate 
S et al. Benefits and harms of breast cancer screening: s systematic 
review. JAMA 2015; 314: 1615-34.
9. Lousdal ML, Kristiansen IS, Møller B, Støvring H. Trends in breast 
cancer stage distribution before, during and after introduction of 
a screening programme in Norway. Eur J Public Health 2014; 24: 
1017-22.
10. Anon. DORA v letu 2016 izpolnila vse zastavljene cilje širitve. Available 
Mar 25, 2017 from: http://dora.onko-i.si/novice/novica/article/142/
index.html?cHash=d525be78f0fef15ce00576373dde5a8d.
11. Cancer incidence in Slovenia 2001. Ljubljana: Institute of Oncology 
Ljubljana, Epidemiology and Cancer Registry, Cancer Registry of 
Republic of Slovenia, 2004.
12. Cancer in Slovenia 2010. Ljubljana: Institute of Oncology Ljubljana, 
Epidemiology and Cancer Registry, Cancer Registry of Republic of 
Slovenia, 2013.
13. Munoz D, Near AM, van Ravesteyn NT, Lee SJ, Schechter CB, Alagoz 
O et al. Effects of screening and systemic adjuvant therapy on ER-
specific US breast cancer mortality. J Natl Cancer Inst 2014; 106: 
dju289.
14. Sant M, Chirlaque Lopez MD, Agresti R, Sánchez Pérez MJ, Holleczek 
B, Bielska-Lasota M et al. Survival of women with cancers of breast 
and genital organs in Europe 1999-2007: results of the EUROCARE-5 
study. Eur J Cancer 2015; 51: 2191-205.
15. Cancer in Slovenia 2009. Ljubljana: Institute of Oncology Ljubljana, 
Epidemiology and Cancer Registry, Cancer Registry of Republic of 
Slovenia, 2013.
16. Imkampe AK, Bates T. Improvements in breast cancer survival over 
time, related to adjuvant treatment and node status. Eur J Surg 
Oncol 2009; 35: 151-5.
17. Taib NA, Akmal M, Mohamed I, Yip CH. Improvement in survival of 
breast cancer patients - trends over two time periods in a single 
institution in an Asia Pacific country, Malaysia. Asian Pac J Cancer 
Prev 2011; 12: 345-9.
18. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG), Darby S, 
McGale P, Correa C, Taylor C, Arriagada R et al. Effect of radiotherapy 
after breast-conserving surgery on 10-year recurrence and 15-year 
breast cancer death: meta-analysis of individual patient data for 
10,801 women in 17 randomised trials. Lancet 2011; 378: 1707-16.
19. Early Breast Cancer Trialists’ Collaborative Group (EBCTCG). Effects 
of chemotherapy and hormonal therapy for early breast cancer on 
recurrence and 15-year survival: an overview of the randomised 
trials. Lancet 2005; 365: 1687-717.
20. Roder DM, de Silva P, Zorbas HM, Kollias J, Malycha PL, Pyke CM et al. 
Age effects on survival from early breast cancer in clinical settings in 
Australia. ANZ J Surg 2012; 82: 524-8.
21. Andersson Y, Frisell J, Sylvan M, de Boniface J, Bergkvist L. Breast 
cancer survival in relation to the metastatic tumor burden in axillary 
lymph nodes. J Clin Oncol 2010; 28: 2868-73.
22. Allemani C, Sant M, Weir HK, Richardson LC, Baili P, Storm H et 
al. Breast cancer survival in the US and Europe: a CONCORD high-
resolution study. Int J Cancer 2013; 132: 1170-81.
23. Bodai BI, Tuso P. Breast cancer survivorship: a comprehensive review 
of long-term medical issues and lifestyle recommendations. Perm J 
2015; 19: 48-79.