METHODS
We recorded clinicopathological and treatment features of the stage I breast cancer patients and evaluated
long-term outcomes retrospectively. Kaplan-Meier analysis and Cox regression analysis were used
for recurrence and overall survival.
RESULTS
308 patients with stage I breast cancer were involved in the study. The average age was 52 (range 21-81).
The median follow-up was 99 (12-380) months. Forty-three (14%) patients were aged over 65, and 162
(52.7%) patients were postmenopausal. ER, PR, and HER2 receptor positivity were 78.9%, 60.8%, and
14.3%, respectively. Lumpectomy plus adjuvant radiotherapy was performed in 82.1% of the patients,
and mastectomy in 10.7% of the patients for primary treatment. The patients received adjuvant chemotherapy
(42.5%) and adjuvant hormonal therapy (79.9%). Recurrence (local-47.8%, metastatic-52.2%)
occurred in 23 (7.5%) patients. In multivariate Cox regression analysis, we found that primary treatment
(lumpectomy + adjuvant RT or mastectomy) (p=0.614), surgical margin status (p=0.495), adjuvant
chemotherapy (p=0.259), and adjuvant hormonal therapy (p=0.289) were not statistically significant
factors for recurrence. However, aged over 65 years (p=0.002) was statistically significant.
CONCLUSION
In this study, we showed long-term outcomes in stage I breast cancer patients. It was shown that the
primary treatment type (lumpectomy + adjuvant RT or mastectomy) was not different in terms of recurrence.
In addition, it was determined that adjuvant chemotherapy did not provide benefit for recurrence
in stage I breast cancer patients in our results. For this reason, in patients with stage I cancer, more care
should be taken in the decision of adjuvant therapy.
Keywords: Adjuvant; breast cancer; chemotherapy; radiotherapy; stage I.
Although there are many factors that determine
the prognosis in breast cancer, early diagnosis of
the disease is one of the most essential factors that
ensure high survival rates.[
The living status of the patients was questioned through the death notification system of the Ministry of Health. From diagnosis time to death time from any cause was defined as overall survival (OS). Disease-free survival (DFS) was accepted as the time from surgery to the recurrence of the disease. Univariable and multivariable analyses were done on clinical, pathological, and treatment-related factors for DFS.
Statistical Analysis
The statistics of the study were performed via SPSS 29
(IBM, Armonk, NY, USA). Continuous variables in
the study were represented by median (as well as minimum
and maximum values) value numbers and percentages,
while categorical variables were described
by numbers and percentages. For survival analysis,
the Kaplan-Meier method was employed. Univariate
and multivariate analysis with the Cox regression
method was performed on clinical and pathological
factors for recurrence. When the p-value was under
0.05, results were accepted as statistically significant,
and the probability ratio was calculated.
Survival Outcomes
The average follow-up was 99 months. During the follow-
up, 24 patients died. The 5-, 10-, and 20-year OS
rates were 97.5%, 90.1%, and 75.9%, respectively (Fig.
OS: Overall survival.
DFS: Disease-free survival.
In patients with ESBC, overtreatment can be applied
to some patients if the adjuvant treatment decision is
not made according to the appropriate criteria for patient
selection. There are two well-defined markers that
show benefit from adjuvant therapy in patients with
ESBC: ER (for endocrine therapy) and HER2 receptor
(for HER2-directed therapy). In a meta-analysis by the
EBCTCG group, it was shown that the use of tamoxifen
for five years in ER-positive breast cancer patients reduced
the risk of breast cancer-related recurrence and
death for 15 years.[
The study had some limitations due to its retrospective
character. The patient group was heterogeneous, and some
data were missing. Due to the small number of patients with recurrence, multivariate analysis was performed
with a limited number of factors. Some of the HER2-positive
patients could not use trastuzumab because they had
been diagnosed in the pre-trastuzumab period.
Ethics Committee Approval: The study was approved by the İstanbul University Institute of Oncology Ethics Committee (no: 1723130, date: 07/04/2023).
Authorship contributions: Concept - İ.D., A.A.; Design - İ.D., A.A.; Supervision - İ.D., N.K., E.A., N.P., F.F., N.A., S.E., K.İ., S.Ö., M.T., H.K., N.C., S.K., M.M., V.Ö., P.S., A.İ., A.A.; Materials - İ.D., N.K., E.A., N.P., F.F., N.A., S.E., K.İ., S.Ö., M.T., H.K., N.C., S.K., M.M., V.Ö., P.S., A.İ., A.A.; Data collection and/or processing - İ.D., N.K., E.A., N.P., F.F., N.A., S.E., K.İ., S.Ö., M.T., H.K., N.C., S.K., M.M., V.Ö., P.S., A.İ., A.A.; Data analysis and/or interpretation - I.D.; Literature search - I.D.; Writing - İ.D., N.K., E.A., N.P., F.F., N.A., S.E., K.İ., S.Ö., M.T., H.K., N.C., S.K., M.M., V.Ö., P.S., A.İ., A.A.; Critical review - İ.D., N.K., E.A., N.P., F.F., N.A., S.E., K.İ., S.Ö., M.T., H.K., N.C., S.K., M.M., V.Ö., P.S., A.İ., A.A.
Conflict of Interest: All authors declared no conflict of interest. Use of AI for Writing Assistance: Not declared.
Financial Support: None declared.
Peer-review: Externally peer-reviewed.