Comparison of initial and sequential salvage brain-directed treatment in patients with 1-4 vs. 5-10 brain metastases from breast cancer (KROG 16-12).

PURPOSE: We aimed to compare the initial and salvage brain-directed treatment and overall survival (OS) between patients with 1-4 brain metastases (BMs) and those with 5-10 from breast cancer (BC). We also organized a decision tree to select the initial whole-brain radiotherapy (WBRT) for these patients. METHODS: Between 2008 and 2014, 471 patients were diagnosed with 1-10 BMs. They were divided into two groups based on the number of BM: 1-4 BMs (n = 337) and 5-10 BMs (n = 134). Median follow-up duration was 14.0 months. RESULTS: Stereotactic radiosurgery (SRS)/fractionated stereotactic radiotherapy (FSRT) was the most common treatment modality (n = 120, 36%) in the 1-4 BMs group. In contrast, 80% (n = 107) of patients with 5-10 BMs were treated with WBRT. The median OS of the entire cohort, 1-4 BMs, and 5-10 BMs was 18.0, 20.9, and 13.9 months, respectively. In the multivariate analysis, the number of BM and WBRT were not associated with OS, whereas triple-negative BC and extracranial metastasis decreased OS. Physicians determined the initial WBRT based on four variables in the following order: number and location of BM, primary tumor control, and performance status. Salvage brain-directed treatment (n = 184), mainly SRS/FSRT (n = 109, 59%), prolonged OS by a median of 14.3 months. CONCLUSION: The initial brain-directed treatment differed notably according to the number of BM, which was chosen based on four clinical factors. In patients with ≤ 10 BMs, the number of BM and WBRT did not affect OS. The major salvage brain-directed treatment modality was SRS/FSRT and increased OS.

Validation of a nomogram for predicting the risk of lymphedema following contemporary treatment for breast cancer: a large multi-institutional study (KROG 20-05).

PURPOSE: We previously constructed a nomogram for predicting the risk of arm lymphedema following contemporary breast cancer treatment. This nomogram should be validated in patients with different background characteristics before use. Therefore, we aimed to externally validate the nomogram in a large multi-institutional cohort. METHODS: Overall, 8835 patients who underwent breast cancer surgery during 2007-2017 were identified. Data of variables in the nomogram and arm lymphedema were collected. The nomogram was validated externally using C-index and integrated area under the curve (iAUC) with 1000 bootstrap samples and by calibration plots. RESULTS: Overall, 1377 patients (15.6%) developed lymphedema. The median time from surgery to lymphedema development was 11.4 months. Lymphedema rates at 2, 3, and 5 years were 11.2%, 13.1%, and 15.6%, respectively. Patients with lymphedema had significantly higher body mass index (median, 24.1 kg/m2 vs. 23.4 kg/m2) and a greater number of removed nodes (median, 17 vs. 6) and more frequently underwent taxane-based chemotherapy (85.7% vs. 41.9%), total mastectomy (73.1% vs. 52.1%), conventionally fractionated radiotherapy (71.9% vs. 54.2%), and regional nodal irradiation (70.7% vs 22.4%) than those who did not develop lymphedema (all P < 0.001). The C-index of the nomogram was 0.7887, and iAUC was 0.7628, indicating good predictive accuracy. Calibration plots confirmed that the predicted lymphedema risks were well correlated with the actual lymphedema rates. CONCLUSION: This nomogram, which was developed using factors related to multimodal breast cancer treatment and was validated in a large multi-institutional cohort, can well predict the risk of breast cancer-related lymphedema.

The Pattern of Care for Brain Metastasis from Breast Cancer over the Past 10 Years in Korea: A Multicenter Retrospective Study (KROG 16-12).

PURPOSE: We aimed to investigate manifestations and patterns of care for patients with brain metastasis (BM) from breast cancer (BC) and compared their overall survival (OS) from 2005 through 2014 in Korea. MATERIALS AND METHODS: We retrospectively reviewed 600 BC patients with BM diagnosed between 2005 and 2014. The median follow-up duration was 12.5 months. We categorized the patients into three groups according to the year when BM was initially diagnosed (group I [2005-2008], 98 patients; group II [2009-2011], 200 patients; and group III [2012-2014], 302 patients). RESULTS: Over time, the median age at BM diagnosis increased by 2.2 years (group I, 49.0 years; group II, 48.3 years; and group III, 51.2 years; p=0.008). The percentage of patients with extracranial metastasis was 73.5%, 83.5%, and 86.4% for group I, II, and III, respectively (p=0.011). The time interval between BC and BM was prolonged in patients with stage III primary BC (median, 2.4 to 3 years; p=0.029). As an initial brain-directed treatment, whole-brain radiotherapy alone decreased from 80.0% in 2005 to 41.1% in 2014. Meanwhile, stereotactic radiosurgery or fractionated stereotactic radiotherapy alone increased from 13.3% to 34.7% during the same period (p=0.005). The median OS for group I, II, and III was 15.6, 17.9, and 15.0 months, respectively, with no statistical significance. CONCLUSION: The manifestations of BM from BC and the pattern of care have changed from 2005 to 2014 in Korea. However, the OS has remained relatively unchanged over the 10 years.

New brain metastases after whole-brain radiotherapy of initial brain metastases in breast cancer patients: the significance of molecular subtypes (KROG 16-12).

PURPOSE: To identify the risk factors leading to new brain metastases (BM) following brain-directed treatment for initial BM resulting from breast cancer (BC). METHODS: In this multi-institutional study, 538 BC patients with available follow-up imaging after brain-directed treatment for initial BM were analyzed. Tumor molecular subtypes were classified as follows: hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-, n = 136), HER2-positive (HER2+, n = 253), or triple-negative BC (TNBC, n = 149). RESULTS: In 37.4% of patients, new BM emerged at a median of 10.5 months after brain-directed treatment for initial BM. The 1-year actuarial rate of new BM for HR+/HER2-, HER2+, and TNBC were 51.9%, 44.0%, and 69.6%, respectively (p = 0.008). Initial whole-brain radiotherapy (WBRT) reduced new BM rates (22.5% reduction at 1 year, p < 0.001) according to molecular subtype (HR+/HER2-, 42% reduction at 1 year, p < 0.001; HER2+, 18.5%, p = 0.004; TNBC, 16.9%, p = 0.071). Multivariate analysis revealed an increased risk of new BM for the following factors: shorter intervals between primary BC diagnoses and BM (p = 0.031); TNBC (relative to HR+/HER2-) (p = 0.016); presence of extracranial metastases (p = 0.019); number of BM (>4) (p < 0.001); and BM in both tentorial regions (p = 0.045). Anti-HER2 therapy in HER2+ patients (p = 0.013) and initial use of WBRT (p < 0.001) significantly lowered new BM development. CONCLUSIONS: Tumor molecular subtypes were associated with both rates of new BM development and the effectiveness of initial WBRT. Anti-HER2 therapy in HER2+ patients significantly lowered new BM occurrence.

Survival outcomes of breast cancer patients with brain metastases: A multicenter retrospective study in Korea (KROG 16-12).

PURPOSE: This study evaluated the influence of prognostic factors and whole brain radiotherapy (WBRT) on overall survival (OS) of breast cancer (BC) patients with brain metastases (BM). METHODS AND MATERIALS: Medical records of 730 BC patients diagnosed with BM from 2000 to 2014 at 17 institutions were retrospectively reviewed. OS was calculated from BM diagnosis. Median follow-up duration was 11.9 months (range, 0.1-126.2). RESULTS: Median OS was 15.0 months (95% CI: 14.0-16.9). Patients with different BC-specific graded prognostic assessment (GPA) scores showed significant differences (p < 0.001) in OS. In multivariate analysis, histologic grade 3 (p = 0.014), presence of extracranial metastasis (p < 0.001), the number of BM (>4; p = 0.002), hormone receptor negativity (p = 0.005), HER2-negativity (p = 0.003), and shorter time interval (<30 months) between BC and BM diagnosis (p = 0.007) were associated with inferior OS. By summing the ß-coefficients of variables that were prognostic in multivariate analyses, we developed a prognostic model that stratified patients into low-risk (≤0.673) and high-risk (>0.673) subgroups; the high-risk subgroup had poorer median OS (10.1 months, 95% CI: 7.9-11.9 vs. 21.9 months, 95% CI: 19.5-27.1, p < 0.001). Univariate and multivariate analyses of propensity score-matched patients diagnosed with BM ≥ 30 months after BC diagnosis (n = 389, "late BM") revealed that WBRT-treated patients showed superior OS compared to non-WBRT-treated patients (p = 0.070 and 0.030, respectively). CONCLUSION: Our prognostic model identified high-risk BC patients with BM who might benefit from increased surveillance; if validated, our model could guide treatment selection for such patients. Patients with late BM might benefit from WBRT as initial local treatment.

The prolyl isomerase Pin1 induces LC-3 expression and mediates tamoxifen resistance in breast cancer.

Endocrine therapies, which inhibit estrogen receptor signaling, are the most common and effective treatments for estrogen receptoralpha-positive breast cancer. However, the utility of these agents is limited by the frequent development of resistance, and the precise mechanisms underlying endocrine therapy resistance remain incompletely understood. Here, we demonstrate that peptidyl-prolyl isomerase Pin1 is an important determinant of resistance to tamoxifen and show that Pin1 increases E2F-4- and Egr-1-driven expression of LC-3 as a result of an increased interaction with and phosphorylation of MEK1/2. In human tamoxifen-resistant breast cancer, our results show a significant correlation between Pin1 overexpression and high levels of LC-3. Promoter activity as well as expression levels of Pin1 were drastically higher in tamoxifen-resistant MCF7 cells than control MCF7 cells, as were levels of LC-3 mRNA and protein, an autophagy marker. Pin1(-/-) mouse embryonic fibroblasts showed lower 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MEK1/2 phosphorylation than Pin1(+/+) mouse embryonic fibroblasts. Silencing of Pin1 expression inhibited TPA-induced MEK1/2 phosphorylation in MCF7 cells. Moreover, PD98059, a specific inhibitor of MEK1/2, and juglone, a potent Pin1 inhibitor, significantly suppressed the TPA-induced expression of E2F-4 as well as Egr-1 transcription factors, which control LC-3 gene expression. Importantly, 4-hydroxy tamoxifen, when used in combination with silencing of Pin1 or LC-3, increased cleaved poly(ADP-ribose) polymerase and DNA fragmentation to inhibit cologenic growth of MCF7 cells. We therefore link the Pin1-MEK pathway and LC-3-mediated tamoxifen resistance and show the therapeutic potential of Pin1 in the treatment of tamoxifen-resistant breast cancer.

Balance of NF-kappaB and p38 MAPK is a determinant of radiosensitivity of the AML-2 and its doxorubicin-resistant cell lines.

This study investigated radioresistance mechanisms in the doxorubicin-resistant acute myelogenous leukemia (AML)-2/DX100. AML-2/DX100 also showed resistance to radiation. AML-2/DX100 characterized by down-regulated catalase expression was supersensitive to exogenous hydrogen peroxide whereas they increased defense mechanisms against endogenous reactive oxygen species (ROS) as compared with AML-2/WT. In AML-2/WT, radiation increased Bax expression and its translocation to mitochondria but had little effect on translocation of Bcl-2 and consequently induced the release of cytochrome c from the mitochondria with the subsequent caspase-3 activation. On the contrary, in AML-2/DX100, radiation neither increased Bax expression nor its translocation to mitochondria while it increased Bcl-2 translocation to mitochondria. A specific p38 MAPK inhibitor SB203580 increased radioresistance in AML-2/WT but little in AML-2/DX100. It inhibited radiation-induced Bax translocation in AML-2/WT but not in AML-2/DX100, indicating that p38 MAPK is working after irradiation in AML-2/WT but not in AML-2/DX100. Electrophoretic mobility shift assay and Western blot analysis revealed that NF-kappaB in AML-2/DX100 was more activated with degradation of cytosolic IkappaBalpha than was that of AML-2/WT. cDNA microarray showed that Bfl-1/A1 and granzyme H in AML-2/DX100 were highly up-regulated (6.21-fold) and down-regulated (6.49-fold), respectively, as compared with each of AML-2/WT, which were confirmed by RT-PCR assay. Taken together, these results indicate that radioresistance mechanisms of AML-2/DX100 could be related to alterations in ROS-scavenging activity, in mitochondrial translocation of Bax and Bcl-2, and in expression of pro-apoptotic (granzyme H) and anti-apoptotic (Bfl-1/A1) genes. It has been shown that balance of p38 MAPK and NF-kappaB signals is a determinant in radiosensitivity of AML-2/WT and AML-2/DX100.

Clinical experience of patients with ductal carcinoma in situ of the breast treated with breast-conserving surgery plus radiotherapy: a preliminary report.

PURPOSE: Breast-conserving therapy (BCT) is a practical alternative to mastectomy for treating ductal carcinoma in situ (DCIS). We reviewed our experience for treating patients with DCIS of the breast to evaluate the outcome after performing breast-conserving surgery plus radiotherapy (BCS-RT). MATERIALS AND METHODS: Between January 1983 and December 2002, 25 patients with clinically or mammographically detected DCIS were treated by BCS-RT. One patient was diagnosed with bilateral DCIS. Thirteen cases (50%) had symptomatic lesions at presentation. All 26 cases of 25 patients underwent BCS such as lumpectomy, partial mastectomy or quadrantectomy. All of them received whole breast irradiation to a median dose of 50.4 Gy. Twenty-four cases (92.3%) received a boost to the tumor bed for a median total dose of 59.4 Gy. The median follow up period was 67 months (range: 38 to 149 months). RESULTS: Two cases (7.7%) experienced ipsilateral breast tumor recurrence (IBTR) after BCS-RT. The histology results at the time of IBTR showed invasive ductal carcinoma (IDC), and the median time to IBTR was 25.5 months. On the univariate analysis, there were no significant factors associated with IBTR in the DCIS patients. The three-year local recurrence free survival rate was 96.0% and the overall survival rate was 96.3%. CONCLUSION: After the treatment for DCIS, the IBTR rate in our study was similar to other previous studies. Considering that we included patients who had many symptomatic lesions, close or positive margins and less that complete early data, our result is comparable to the previous studies. We could not find the prognostic significant factors associated with IBTR after BCS-RT. A longer follow up period with more patients would be required to evaluate the role of any predictive factors and to confirm these short-term results.

Anti-oxidant adaptation in the AML cells supersensitive to hydrogen peroxide.

The purpose of this study was to investigate the adaptive mechanisms of hydrogen peroxide-supersensitive AML cells against the reactive oxygen species (ROS). Their scavenging capacity against ROS was determined using a fluorometric probe in the doxorubicin-resistant AML-2/DX100 cell characterized by the down-regulation of catalase. AML-2/DX100 cells had more scavenging capacity against endogenous pro-oxidants than did the parental cells AML-2/WT, suggesting that an anti-oxidant adaptation against ROS occurred. cDNA microarrays for 8000 human genes revealed that among 21 anti-oxidant genes, each four gene was up- and down-regulated more than 1.5-fold in AML-2/DX100 compared with AML-2/WT. The mRNA expression of glutathione S-transferase Pi, peroxiredoxin 2, thioredoxin 2, and glutaredoxin was elevated whereas that of peroxiredoxin 3, metallothionein-1F, superoxide dismutase 2, and thioredoxin reductase 1 was depressed. The result indicates that the down-regulation of certain anti-oxidant mechanisms can be compensated for by the up- and down-regulation of the other anti-oxidant mechanisms.

Results of Curative Radiotherapy Alone in Patients with Uterine Cervical Carcinomas.

PURPOSE: To evaluate the role of curative radiotherapy alone in the treatment of uterine cervical carcinomas, by a retrospective analysis with respects to survival and pelvic control, and to find any risk factors of failure. MATERIALS AND METHODS: Between Jan. 1990 and Dec. 1995, a total of 187 patients, diagnosed with uterine cervical carcinomas in FIGO stages greater than IA, were treated by curative radiotherapy alone with no chemotherapy. The ages of the patients ranged from 26 to 80 years, with a median of 60 years. The number of patients diagnosed with squamous cell carcinomas were 183 (97.9%). The number of patients with FIGO stage IB1, IB2, IIA, IIB, IIIA, IIIB and IVA were 61 (32.6%), 7 (3.7%), 43 (23.0%), 62 (33.3%), 3 (1.6%), 7 (3.7%) and 4 (2.1%), respectively. External radiotherapy was performed with 6 MV or 10 MV X-rays, with a dose range of 19.8 Gy~ 50.4 Gy (median; 30.6), to whole pelvis. Intracavitary radiation (ICR) was then performed using a high-dose rate remote controlled afterloader with radioisotopes of Co-60 and Cs-137. The fraction size of the ICR was 5 Gy twice a week, and was delivered up to total doses of 10 Gy~ 55 Gy (median; 40). After the ICR, additional pelvic external radiotherapy with midline shielding width of 4 cm was performed with the dose range of 0~30.6 Gy (median; 19.8), and the resultant total doses of A points ranged between 49.8 Gy and 86.0 Gy (median; 70.6). RESULTS: The five-year overall survival rates of FIGO IB1, IB2, IIA, IIB, III and IVA were 88.3%, 83.3%, 86.1%, 65.2%, 60.0% and 50.0%, respectively (p=0.005). The pelvic control rates of each stage were 90.1%, 85.7%, 86.1%, 69.4%, 68.6% and 50.0%, respectively (p=0.03). From the multivariate analysis, the radiation response and tumor diameter were found to be significant factors affecting the overall survival. The significant factors influencing pelvic control were the radiation response and pre-treatment hemoglobin level. CONCLUSION: The radiation response and tumor diameter were significant factors affecting survival, so patients with tumor diameters greater than 4 cm should be considered for a combined modality, such as concurrent chemoradiotherapy.