Impact of the New ESTRO-ACROP Target Volume Delineation Guideline on Breast-Related Complications after Implant-Based Reconstruction and Postmastectomy Radiotherapy

PURPOSE/OBJECTIVE(S)

The European Society for Radiotherapy and Oncology Advisory Committee in Radiation Oncology Practice (ESTRO-ACROP) recently updated a new target volume delineation guideline for postmastectomy radiotherapy (PMRT) after implant-based reconstruction. This study aimed whether this change has impact on breast-related complications.

MATERIALS/METHODS

We retrospectively reviewed patients who underwent PMRT after mastectomy with tissue expander or permanent implant insertion from 2016 to 2021. In total, 412 patients were included; 277 received RT by the new ESTRO-ACROP target delineation (ESTRO-T), and 135 received RT by conventional target delineation (CONV-T). The primary endpoint was comparison between the target groups of major breast-related complication, including infection, capsular contracture, deformity and necrosis requiring re-operation or re-hospitalization during follow-up after RT or delayed implant replacement. Complications were evaluated according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0., and capsular contracture was graded by the Baker Classification.

RESULTS

The median follow-up was 29.5 months (range, 0.3-76.8). The 1-, 2-, and 3-year incidence rates of major breast-related complication were 5.7%, 10.0%, and 11.6% in the ESTRO-T group, and 8.2%, 13.8%, and 14.7% in the CONV-T groups; it did not show a difference between the groups (P = 0.55). In multivariate analyses, target delineation is not significantly associated with the major complications (hazard ratio [HR] = 0.93; P = 0.83, Table 1). There was no significant difference between the ESTRO-T and CONV-T groups in the incidence of any breast-related complications (3-year cumulative incidence, 37.3% vs. 29.4%, respectively; P = 0.28). Symptomatic RT-induced pneumonitis rates were 2.7% in the ESTRO-T group (7 patients) and 2.2% in the CONV-T group (3 patients). Only one local recurrence event occurred in the ESTRO-T group, which was within the ESTRO-target volume.

CONCLUSION

Target volume delineation according to the new ESTRO-ACROP guideline did not reduce the risk of major or any breast-related complications. As the dosimetric benefits of heart and lung have been reported, further analyses with long-term follow-up are necessary to evaluate whether it could be connected to better clinical outcomes.

Pattern and Complication of Reconstructed Breast Cancer Patients Who Received Postmastectomy Radiotherapy in the National Health Insurance Service Cohort

PURPOSE/OBJECTIVE(S)

This study aimed to analyze the nationwide pattern of reconstruction after mastectomy in patients with breast cancer who received postmastectomy radiotherapy (PMRT) and to compare complications according to fractionation and reconstruction procedures.

MATERIALS/METHODS

By using claim data from the National Health Insurance Service (NHIS) database, we analyzed breast cancer patients who received PMRT and underwent reconstruction between 2015 and 2020. We defined the grade ≥ 3 complications as the primary endpoint which involved hospital admission to the plastic surgery department. The complication was identified by using the procedure code for debridement and the International Classification of Diseases 10th codes for wound infections, dehiscence, necrosis, and mechanical complication of breast prosthesis and implant. The propensity score matching method was adopted to constitute the matched cohort between the hypofractionated fractionation (HF) and the conventional fractionation (CF), adjusted for age, diabetes, hypertension, obesity, smoking history, PMRT technique, use of bolus, year of PMRT delivery, and reconstruction method. Logistic regression was performed to evaluate the association between complication and variables.

RESULTS

Altogether 4,553 patients were analyzed: 1,395 (30.6%) in the HF group and 3,158 (69.4.%) in the CF group. The use of HF has steadily increased from 20.1% in 2015 to 42.2% in 2020. Immediate implant reconstruction (36.8%) method was the most frequently used, followed by immediate autologous (33.3%) and two-stage implant reconstruction methods (19.6%). In the matched cohort (N = 2,052), the major complication rate was not significantly different between the HF group and the CF group (5.9% [60/1,026] vs. 5.4% [55/1,026], P = 0.568) with the median follow-up of 30.9 months (range, 6.0-82.1). Surgical debridement was performed in 3.3% [34/1026] of the HF group and 3.5% [36/1026] of the CF group (P = 0.808). HF was not associated with major complications (odds ratio (OR) 1.09, 95% CI 0.75-1.59, P = 0.128).

CONCLUSION

In a nationwide insurance cohort, the complication rate was not significantly different between the HF group and the CF group. Our data suggest HF for reconstructed breasts is comparable to CF. However, consultation for fractionation regimen for reconstructed breast cancer patients may be still required at time of consideration of PMRT.

Patterns and Longitudinal Changes in The Practice of Breast Cancer Radiotherapy in Korea: Korean Radiation Oncology Group 22-01

PURPOSE/OBJECTIVE(S)

To analyze contemporary practice patterns in breast cancer radiotherapy (RT) and to assess longitudinal changes therein over 5 years in Korea.

MATERIALS/METHODS

A nationwide survey was conducted among board-certified radiation oncologists in Korea by the Division for Breast Cancer of the Korean Radiation Oncology Group in March 2022. The survey consisted of 44 questions related to six domains: hypofractionated (HypoFx) whole breast RT, accelerated partial breast RT (APBI), regional nodal irradiation (RNI), RT for ductal carcinoma in situ (DCIS), postmastectomy RT (PMRT), and tumor bed boost.

RESULTS

In total, 70 radiation oncologists from 61 of 101 (60%) institutions participated in the survey. HypoFx RT was used by 62 respondents (89%), which has significantly increased from 36% in 2017. The HypoFx RT was commonly administered at 40-42.5 Gy in 15-16 fractions. APBI was used by 12 respondents (17%), which has increased from 5% in 2017. The use of RNI did not change significantly: ≥ pN2 (6%), ≥ pN1 (33%), and ≥ pN1 with pathological risk factors (61%). However, the indications for use of internal mammary lymph node (IMN) irradiation have expanded. In particular, the rates of routine treatment of IMN (11% from 6% in 2017) and treatment in cases of ≥ pN2 (27% from 14% in 2017) have doubled; however, the rate of treatment for only IMN involvement, identified on imaging, has decreased to 31% from 47% in 2017. With regard to DCIS, the use of hypoFx RT increased to 75% from 25%, and the rate of omission on of RT after breast-conserving surgery decreased to 38% from 48% in 2017. The use of hypoFx RT for PMRT also increased to 36% from 8% in 2017.

CONCLUSION

The adoption of HypoFx RT after breast-conserving surgery in invasive breast cancer and DCIS has increased significantly, whereas that for PMRT has increased moderately, compared to 2017. Further studies are required to determine the optimal use of RNI.

Role of nociceptin/orphanin FQ and nociceptin opioid peptide receptor in depression and antidepressant effects of nociceptin opioid peptide receptor antagonists

Nociceptin/orphanin FQ (N/OFQ) and its receptor, nociceptin opioid peptide (NOP) receptor, are localized in brain areas implicated in depression including the amygdala, bed nucleus of the stria terminalis, habenula, and monoaminergic nuclei in the brain stem. N/OFQ inhibits neuronal excitability of monoaminergic neurons and monoamine release from their terminals by activation of G protein-coupled inwardly rectifying K⁺ channels and inhibition of voltage sensitive calcium channels, respectively. Therefore, NOP receptor antagonists have been proposed as a potential antidepressant. Indeed, mounting evidence shows that NOP receptor antagonists have antidepressant-like effects in various preclinical animal models of depression, and recent clinical studies again confirmed the idea that blockade of NOP receptor signaling could provide a novel strategy for the treatment of depression. In this review, we describe the pharmacological effects of N/OFQ in relation to depression and explore the possible mechanism of NOP receptor antagonists as potential antidepressants.

Porphyromonas gingivalis Impairs Oral Epithelial Barrier through Targeting GRHL2

Oral mucosa provides the first line of defense against a diverse array of environmental and microbial irritants by forming the barrier of epithelial cells interconnected by multiprotein tight junctions (TJ), adherens junctions, desmosomes, and gap junction complexes. Grainyhead-like 2 (GRHL2), an epithelial-specific transcription factor, may play a role in the formation of the mucosal epithelial barrier, as it regulates the expression of the junction proteins. The current study investigated the role of GRHL2 in the Porphyromonas gingivalis (Pg)-induced impairment of epithelial barrier functions. Exposure of human oral keratinocytes (HOK-16B and OKF6 cells) to Pg or Pg-derived lipopolysaccharides (Pg LPSs) led to rapid loss of endogenous GRHL2 and the junction proteins (e.g., zonula occludens, E-cadherin, claudins, and occludin). GRHL2 directly regulated the expression levels of the junction proteins and the epithelial permeability for small molecules (e.g., dextrans and Pg bacteria). To explore the functional role of GRHL2 in oral mucosal barrier, we used a Grhl2 conditional knockout (KO) mouse model, which allows for epithelial tissue-specific Grhl2 KO in an inducible manner. Grhl2 KO impaired the expression of the junction proteins at the junctional epithelium and increased the alveolar bone loss in the ligature-induced periodontitis model. Fluorescence in situ hybridization revealed increased epithelial penetration of oral bacteria in Grhl2 KO mice compared with the wild-type mice. Also, blood loadings of oral bacteria (e.g., Bacteroides, Bacillus, Firmicutes, β-proteobacteria, and Spirochetes) were significantly elevated in Grhl2 KO mice compared to the wild-type littermates. These data indicate that Pg bacteria may enhance paracellular penetration through oral mucosa in part by targeting the expression of GRHL2 in the oral epithelial cells, which then impairs the epithelial barrier by inhibition of junction protein expression, resulting in increased alveolar tissue destruction and systemic bacteremia.

Abstract P3-12-12: Impact of regional nodal irradiation for breast cancer patients with supraclavicular and/or internal mammary lymph node involvement: A multicenter, retrospective study (KROG 16-14)

Purpose: To evaluate the treatment outcomes of radiotherapy (RT) for breast cancer with ipsilateral supraclavicular (SCL) and/or internal mammary (IMN) lymph node involvement.

Methods: A total of 353 patients from 11 institutions were included. One hundred and thirty-six patients had SCL involvement, 148 had IMN involvement, and 69 had both. All patients received neoadjvant systemic therapy followed by breast conserving surgery or mastectomy, and postoperative RT to whole breast/chest wall. As for regional lymph node irradiation, SCL RT was given to 344 patients, and IMN RT to 236 patients. The median RT dose was 50.4 Gy.

Results: The median follow-up duration was 61 months (range, 7-173). In-field progression was present in SCL (n=20) and/or IMN (n=7). The 5-year disease-free survival (DFS) and overall survival rates were 57.8% and 75.1%, respectively. On multivariate analysis, both SCL/IMN involvement, number of axillary lymph node ≥4, triple negative subtype, and mastectomy were significant adverse prognosticators for DFS (p = 0.022, 0.001, 0.001, and 0.004, respectively). Regarding the impact of regional nodal irradiation, SCL RT dose ≥54 Gy was not associated with DFS (5-yr rate, 52.9% vs. 50.9%, p = 0.696) in SCL-involved patients, and the receipt of IMN RT was not associated with DFS (5-yr rate, 56.1% vs. 78.1%, p = 0.099) in IMN-involved patients.

Conclusion: Neoadjuvant chemotherapy followed by surgery and postoperative RT achieved an acceptable in-field regional control rate in patients with SCL and/or IMN involvement. However, a higher RT dose to SCL or IMN RT was not associated with the improved DFS in these patients.

Citation Format: Kim K, Jeong Y, Shin KH, Kim JH, Ahn SD, Kim SS, Suh C-O, Kim YB, Choi DH, Park W, Cha J, Chun M, Lee DS, Lee SY, Kim JH, Park HJ. Impact of regional nodal irradiation for breast cancer patients with supraclavicular and/or internal mammary lymph node involvement: A multicenter, retrospective study (KROG 16-14) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-12-12.

Human Papillomavirus 16 E6 Induces FoxM1B in Oral Keratinocytes through GRHL2

High-risk human papillomavirus (HPV) is a major risk factor for oral and pharyngeal cancers (OPCs), yet the detailed mechanisms by which HPV promotes OPCs are not understood. Forkhead box M1B (FoxM1B) is an oncogene essential for cell cycle progression and tumorigenesis, and it is aberrantly overexpressed in many tumors. We previously showed that FoxM1B was the putative target of an epithelial-specific transcription factor, Grainyhead-like 2 (GRHL2). In the current study, we demonstrate that HPV type 16 (HPV-16) E6 induces FoxM1B in human oral keratinocytes (HOKs) and tonsillar epithelial cells (TECs) in part through GRHL2. FoxM1B was barely detectable in cultured normal human oral keratinocytes (NHOKs) and progressively increased in immortalized HOKs harboring HPV-16 genome (HOK-16B) and tumorigenic HOK-16B/BaP-T cells. Retroviral expression of HPV-16 E6 and/or E7 in NHOKs, TECs, and hypopharyngeal carcinoma cells (FaDu) revealed induction of FoxM1B and GRHL2 by the E6 protein but not E7. Both GRHL2 and FoxM1B were strongly induced in the epidermis of HPV-16 E6 transgenic mice and HPV⁺ oral squamous cell carcinomas. Ectopic expression of FoxM1B led to acquisition of transformed phenotype in HOK-16B cells. Loss of FoxM1B by lentiviral short hairpin RNA vector or chemical inhibitor led to elimination of tumorigenic characteristics of HOK-16B/BaP-T cells. Luciferase reporter assay revealed that GRHL2 directly bound and regulated the FoxM1B gene promoter activity. Using epithelial-specific Grhl2 conditional knockout mice, we exposed wild-type (WT) and Grhl2 KO mice to 4-nitroquinolin 1-oxide (4-NQO), which led to induction of FoxM1B in the tongue tissues and rampant oral tumor development in the WT mice. However, 4-NQO exposure failed to induce tongue tumors or induction of FoxM1B expression in Grhl2 KO mice. Collectively, these results indicate that HPV-16 induces FoxM1B in part through GRHL2 transcriptional activity and that elevated FoxM1B level is required for oropharyngeal cancer development.

Exploration of Biomarkers for Amoxicillin/Clavulanate-Induced Liver Injury: Multi-Omics Approaches

To explore potential biomarkers for amoxicillin/clavulanate‐induced liver injury (AC‐DILI), we conducted a clinical trial in 32 healthy subjects based on multi‐omics approaches. Every subject was administered amoxicillin/clavulanate for 14 days. The liver‐specific microRNA‐122 (miR‐122) level increased prior to and correlated well with the observed alanine aminotransferase (ALT) level increase. This result indicates its potential as a sensitive early marker for AC‐DILI. We also identified urinary metabolites, such as azelaic acid and 7‐methylxanthine, with levels that significantly differed among the groups classified by ALT elevation level on day 8 after drug administration (P < 0.05). Lymphocyte proliferation in response to the drug was also observed. These findings demonstrate sequential changes in the process of AC‐DILI, including metabolic changes, increased miR‐122 level, increased liver enzyme activity, and enhanced lymphocyte proliferation after drug administration. In conclusion, this study provides potential biomarkers for AC‐DILI based on currently known mechanisms using comprehensive multi‐omics approaches.

Efficacy of Pre- and Postoperative Chemotherapy in Patients with Osteosarcoma of the Extremities

PURPOSE

We evaluated the treatment efficacy including survival and recurrence, and factors associated with recurrence in osteosarcoma patients treated with preoperative chemotherapy, surgery, and adjuvant chemotherapy.

MATERIALS AND METHODS

Forty nine patients with osteosarcoma were treated with preoperative chemotherapy with intra-arterial cisplatin and adriamycin infusion for 3 cycles, followed by surgery. According to the pathologic response, if tumor was necrotized more than 90%, the same adjuvant chemotherapy was reintroduced for 3 cycles, and if the response was not enough, then the salvage regimen was introduced. Plain chest film and chest CT scan were taken monthly and every 3 months, respectively. When tumor recurred, the metastasectomy was performed whenever possible.

RESULTS

Forty three patients were evaluable with amedian follow up of 53 months. Five-year disease-free and overallsurvival rate was 47.0% and 66.9%, respectively. The recurrence was observed in 22 patients (51.2%) with median time of 12.5 months. Baseline alkaline phosphatase (ALP) was the only significant factor for recurrence (p=0.03) and the patients with the possibility of metastasectomy recurrence showed higher post-relapse survival compared to other treatment modalities (26 momths vs 5~12 months).

CONCLUSION

These results indicates that pre- and postoperative chemotherapy with intra-arterial cisplatin and adriamycin infusion showed comparable treatment efficacy and acceptable toxicities.

Increase in cocaine- and amphetamine-regulated transcript (CART) in specific areas of the mouse brain by acute caffeine administration

Caffeine produces a variety of behavioral effects including increased alertness, reduced food intake, anxiogenic effects, and dependence upon repeated exposure. Although many of the effects of caffeine are mediated by its ability to block adenosine receptors, it is possible that other neural substrates, such as cocaine- and amphetamine-regulated transcript (CART), may be involved in the effects of caffeine. Indeed, a recent study demonstrated that repeated caffeine administration increases CART in the mouse striatum. However, it is not clear whether acute caffeine administration alters CART in other areas of the brain. To explore this possibility, we investigated the dose- and time-dependent changes in CART immunoreactivity (CART-IR) after a single dose of caffeine in mice. We found that a high dose of caffeine (100 mg/kg) significantly increased CART-IR 2 h after administration in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), central nucleus of the amygdala (CeA), paraventricular hypothalamic nucleus (PVN), arcuate hypothalamic nucleus (Arc), and locus coeruleus (LC), and returned to control levels after 8 h. But this increase was not observed in other brain areas. In addition, caffeine administration at doses of 25 and 50 mg/kg appears to produce dose-dependent increases in CART-IR in these brain areas; however, the magnitude of increase in CART-IR observed at a dose of 50 mg/kg was similar or greater than that observed at a dose of 100 mg/kg. This result suggests that CART-IR in AcbSh, dBNST, CeA, PVN, Arc, and LC is selectively affected by caffeine administration.

Desipramine and citalopram attenuate pretest swim-induced increases in prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis and the lateral division of the central nucleus of the amygdala in the forced swimming test

Dynorphin in the nucleus accumbens shell plays an important role in antidepressant-like effect in the forced swimming test (FST), but it is unclear whether desipramine and citalopram treatments alter prodynorphin levels in other brain areas. To explore this possibility, we injected mice with desipramine and citalopram 0.5, 19, and 23 h after a 15-min pretest swim and observed changes in prodynorphin expression before the test swim, which was conducted 24 h after the pretest swim. The pretest swim increased prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis (dBNST) and lateral division of the central nucleus of the amygdala (CeL). This increase in prodynorphin immunoreactivity in the dBNST and CeL was blocked by desipramine and citalopram treatments. Similar changes in prodynorphin mRNA levels were observed in the dBNST and CeL, but these changes did not reach significance. To understand the underlying mechanism, we assessed changes in phosphorylated CREB at Ser(133) (pCREB) immunoreactivity in the dBNST and central nucleus of the amygdala (CeA). Treatment with citalopram but not desipramine after the pretest swim significantly increased pCREB immunoreactivity only in the dBNST. These results suggest that regulation of prodynorphin in the dBNST and CeL before the test swim may be involved in the antidepressant-like effect of desipramine and citalopram in the FST and suggest that changes in pCREB immunoreactivity in these areas may not play an important role in the regulation of prodynorphin in the dBNST and CeA.

Effect of acute and chronic electroconvulsive shock on 5-hydroxytrypamine 6 receptor immunoreactivity in rat hippocampus

Electroconvulsive shock (ECS) induces not only an antidepressant effect but also adverse effects such as amnesia. One potential mechanism underlying both the antidepressant and amnesia effect of ECS may involve the regulation of serotonin (5-hydroxytryptamine) 6 (5-HT6) receptor, but less is known about the effects of acute ECS on the changes in 5-HT6 receptor expression in the hippocampus. In addition, as regulation of 5-HT receptor expression is influenced by the number of ECS treatment and by interval between ECS treatment and sacrifice, it is probable that magnitude and time-dependent changes in 5-HT6 receptor expression could be influenced by repeated ECS exposure. To explore this possibility, we observed and compared the changes of 5-HT6 receptor immunoreactivity (5-HT6 IR) in rat hippocampus at 1, 8, 24, or 72 h after the treatment with either a single ECS (acute ECS) or daily ECS for 10 days (chronic ECS). We found that acute ECS increased 5-HT6 IR in the CA1, CA3, and granule cell layer of hippocampus, reaching peak levels at 8 h and returning to basal levels 72 h later. The magnitude and time-dependent changes in 5-HT6 IR observed after acute ECS were not affected by chronic ECS. These results demonstrate that both acute and chronic ECS transiently increase the 5-HT6 IR in rat hippocampus, and suggest that the magnitude and time-dependent changes in 5-HT6 IR in the hippocampus appear not to be influenced by repeated ECS treatment.

Effect of desipramine and citalopram treatment on forced swimming test-induced changes in cocaine- and amphetamine-regulated transcript (CART) immunoreactivity in mice

Recent study demonstrates antidepressant-like effect of cocaine- and amphetamine-regulated transcript (CART) in the forced swimming test (FST), but less is known about whether antidepressant treatments alter levels of CART immunoreactivity (CART-IR) in the FST. To explore this possibility, we assessed the treatment effects of desipramine and citalopram, which inhibit the reuptake of norepinephrine and serotonin into the presynaptic terminals, respectively, on changes in levels of CART-IR before and after the test swim in mouse brain. Levels of CART-IR in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), and hypothalamic paraventricular nucleus (PVN) were significantly increased before the test swim by desipramine and citalopram treatments. This increase in CART-IR in the AcbSh, dBNST, and PVN before the test swim remained elevated by desipramine treatment after the test swim, but this increase in these brain areas returned to near control levels after test swim by citalopram treatment. Citalopram, but not desipramine, treatment increased levels of CART-IR in the central nucleus of the amygdala (CeA) and the locus ceruleus (LC) before the test swim, and this increase was returned to control levels after the test swim in the CeA, but not in the LC. These results suggest common and distinct regulation of CART by desipramine and citalopram treatments in the FST and raise the possibility that CART in the AcbSh, dBNST, and CeA may be involved in antidepressant-like effect in the FST.

Is elective nodal irradiation beneficial in patients with pathologically negative lymph nodes after neoadjuvant chemotherapy and breast-conserving surgery for clinical stage II-III breast cancer? A multicentre retrospective study (KROG 12-05)

BACKGROUND

To evaluate the effects of elective nodal irradiation (ENI) in clinical stage II-III breast cancer patients with pathologically negative lymph nodes (LNs) (ypN0) after neoadjuvant chemotherapy (NAC) followed by breast-conserving surgery (BCS) and radiotherapy (RT).

METHODS

We retrospectively analysed 260 patients with ypN0 who received NAC followed by BCS and RT. Elective nodal irradiation was delivered to 136 (52.3%) patients. The effects of ENI on survival outcomes were evaluated.

RESULTS

After a median follow-up period of 66.2 months (range, 15.6-127.4 months), 26 patients (10.0%) developed disease recurrence. The 5-year locoregional recurrence-free survival and disease-free survival (DFS) for all patients were 95.5% and 90.5%, respectively. Pathologic T classification (0-is vs 1 vs 2-4) and the number of LNs sampled (<13 vs ≥13) were associated with DFS (P=0.0086 and 0.0012, respectively). There was no significant difference in survival outcomes according to ENI. Elective nodal irradiation also did not affect survival outcomes in any of the subgroups according to pathologic T classification or the number of LNs sampled.

CONCLUSIONS

ENI may be omitted in patients with ypN0 breast cancer after NAC and BCS. But until the results of the randomised trials are available, patients should be put on these trials.

Abstract P3-08-14: Could the preoperative systemic therapy be a risk factor for breast cancer-related lymphedema in stage II/III breast cancer?

Background: The breast cancer-related lymphedema (LE) has been known to be closely related to axillary lymph nodes dissection (ALND), chemotherapy, and radiation therapy. In this study, we evaluated whether the sequence of systemic chemotherapy and surgery could be a predictive factor in stage II/III breast cancer.

Methods and Materials: A total of 867 patients with stage II/III breast cancer, who underwent curative surgery with adequate systemic therapy from 2004 to 2009, were retrospectively analyzed. Adjuvant chemotherapy (ACT) was performed in 571 patients (65.9%) and preoperative systemic chemotherapy (PSC) in 296 (34.1%). We evaluated the incidence of LE by clinicopathologic factors and treatments.

Results: At a median follow-up of 5.1 years (range, 3.0-8.3 years), 360 patients (41.5%) had experienced LE, 244 patients have retained LE (permanent LE), and 116 patents were normalized. The overall 5-year cumulative incidence of LE was 17%. LE occurred in 188 patients (32.9%) in patients with ACT, 172 patients (58.1%) with PSC (P&lt;0.001), permanent LE in 121 (21.2%) with ACT, 123 (41.6%) with PSC (P&lt;0.001), respectively. Multivariate analysis showed that PSC (hazard ratio [HR], 1.65; P&lt;.001), radiotherapy (HR, 2.24; P&lt;0.01), ALND (HR, 1.41; P = 0.04), and nodal stage (HR, 1.93; P = 0.04) were independent risk factors for LE occurrence. For the permanent LE, PSC (HR, 1.44; P = 0.05), radiotherapy (HR, 2.79; P&lt;0.01), ALND (HR, 1.77; P&lt;0.01), and nodal stage (HR, 3.01; P = 0.02) showed the associations.

Conclusions: The risk factors associated with LE were advanced stage, ALND and radiotherapy. PSC was one of predictors for transients LE. However, further evaluation should be done whether it is a risk factor for permanent LE.

This research was supported by National Cancer Center Grant NCC-1210181-2 by the National Cancer Center, Republic of Korea.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-08-14.

Abstract P5-16-03: Influence of radiotherapy boost in patients with ductal carcinoma in situ of breast cancer: A multicenter, retrospective study in Korea (KROG 11-04)

Purpose

We aimed to estimate the effect of boost radiotherapy on local relapse-free survival (LRFS) in patients with ductal carcinoma in situ (DCIS) of breast cancer.

Material and Methods

We included patients from 8 institutions who met the following inclusion criteria: having tumor status Tis, age 18 years or older at diagnosis, having had breast conserving surgery (BCS) and radiotherapy within 12 weeks after surgery. From January 1995 through December 2006, 594 patients with DCIS breast cancer treated with BCS and radiotherapy were analyzed retrospectively in a study by Korean Radiation Oncology Group (KROG). All patients received whole breast radiotherapy (median 5040 cGy) after BCS. Among them, 154 patients (25.9%) received boost radiotherapy (median 1000 cGy) after whole breast radiotherapy. Patients who received boost radiotherapy had higher tumor grade, more comedo pattern and less papillary pattern. Other patients’ or tumor characteristics were not statistically different between boost group and no boost group.

Results

After median follow-up of 89 months (range 26-200), 5 year and 10 year LRFS was 98.3% and 95.6%. There was no statistically significant difference of LRFS between boost group and no boost group.

Local relapse free survival according to boost radiotherpay 5-year LRFS* (%)10-year LRFS (%)p-value**Boost group98.196.20.626No boost group98.495.4 *Local relapse free survival, **Log-rank test

Nineteen (3.2%) patients had ipsilateral breast recurrences, of whom, 12 patients had invasive breast cancer and 7 had DCIS. Positive HER2 receptor was associated with higher invasive recurrences.

Ipsilateral breast recurrences according to HER2 receptor TotalHER2 receptor (+)HER2 receptor (-)p-value*Ipsilateral breast121110.017Invasive8800.023DCIS**4310.642*Fisher's exact test, **Ductal carcinoma in situ

Nine (1.5%) patients developed contralateral breast cancer, of whom, 6 were invasive breast cancer and 3 were DCIS. On multivariate analysis, only margin status was a significant prognostic factor for LRFS.

Conclusion

In the absence of randomized trials, boost radiotherapy could not decrease local recurrence in DCIS of breast cancer after BCS and radiotherapy. In addition, patients with positive HER2 receptor would need further treatment like target agent, trastuzumab. NSABP B-43 study result would answer the question.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-16-03.

Changes in c-Fos Expression in the Forced Swimming Test: Common and Distinct Modulation in Rat Brain by Desipramine and Citalopram

Rodents exposed to a 15-min pretest swim in the forced swimming test (FST) exhibit prolonged immobility in a subsequent 5-min test swim, and antidepressant treatment before the test swim reduces immobility. At present, neuronal circuits recruited by antidepressant before the test swim remain unclear, and also less is known about whether antidepressants with different mechanisms of action could influence neural circuits differentially. To reveal the neural circuits associated with antidepressant effect in the FST, we injected desipramine or citalopram 0.5 h, 19 h, and 23 h after the pretest swim and observed changes in c-Fos expression in rats before the test swim, namely 24 h after the pretest swim. Desipramine treatment alone in the absence of pretest swim was without effect, whereas citalopram treatment alone significantly increased the number of c-Fos-like immunoreactive cells in the central nucleus of the amygdala and bed nucleus of the stria terminalis, where this pattern of increase appears to be maintained after the pretest swim. Both desipramine and citalopram treatment after the pretest swim significantly increased the number of c-Fos-like immunoreactive cells in the ventral lateral septum and ventrolateral periaqueductal gray before the test swim. These results suggest that citalopram may affect c-Fos expression in the central nucleus of the amygdala and bed nucleus of the stria terminalis distinctively and raise the possibility that upregulation of c-Fos in the ventral lateral septum and ventrolateral periaqueductal gray before the test swim may be one of the probable common mechanisms underlying antidepressant effect in the FST.

Volumetric response evaluation after intensity modulated radiotherapy in patients with supratentorial gliomas

Radiotherapy is frequently indicated to treat cerebral gliomas. Accurate response evaluation after radiotherapy is essential to determine the efficacy of treatment. We retrospectively analyzed the volumetric tumor response after simultaneous integrated boost-intensity modulated radiotherapy (SIB-IMRT) in patients with gliomas. Thirty-five patients (Grade II, 7 patients; Grade III, 12; and Grade IV, 16) were treated with SIB-IMRT with a median total dose of 55.9 Gy/26 fractions for Grade II and 60 Gy/25 fractions for Grade III-IV tumors. Tumor responses were evaluated for enhancing volume on post-gadolinium T1-weighted images (Vgd) and hyper-intensity volume on T2-weighted FLAIR images (V(fl)) on serial MRIs. With the median follow-up of 24.0 months, overall response rates (RRs) were 57% for V(gd) and 51% for V(fl). Tumor grade was predictive of response favoring the lower grade in Vfl with RRs of 86% for Grade II, 75% for Grade III, and 19% for Grade IV tumors (p = 0.004). Time to 50% or greater volume reduction (T50) in Vgd was 8 months for grade III. The T50 in V(fl) was approximately 24 months both for Grade II and III tumors. Majority of Grade IV tumors continued to progress and never reached the T50 in Vgd or Vfl. Responders survived longer than non-responders for V(gd) and V(fl). Volume response after radiotherapy was dependent upon tumor grade and time. LGGs are very responsive to radiotherapy with the RRs of 86% in V(fl). The response of Vfl is more protracted compared to V(gd). Further investigation is needed to determine the clinical significance of volumetric response evaluation.

P4-17-12: Analysis of Predictive and Prognostic Factors for Metastatic Breast Cancer Patients with Brain Metastasis Treated by Whole Brain Radiotherapy

Background We addressed the progression free survival of brain metastasis (PFS_BM) in metastatic breast cancer (MBC) patients treated by whole brain radiotherapy (WBRT) for brain metastasis (BM). In addition, we investigated predictive and prognostic factors for the PFS_BM and OS_BM.

Patients and methods A total of 212 patients with BM, treated by WBRT at the National Cancer Center between January 2000 and December 2010 were reviewed. The PFS_BM was defined as the time interval from the date of start of WBRT to the date of a progression of metastatic lesions in the brain or death or last follow-up.

Results The median age of patients was 45 years (range, 22–72 years) and the median time to brain metastasis was 12.7 months (range, 0.0−72.8 months).

Abstract P4-09-14: Invasive Lobular Carcinoma Is a Prototype of Luminal A Breast Cancer Subtype and Rare in Korea

Purpose Invasive lobular carcinoma (ILC) is known to be the second most frequent histologic subtype, occupying 10% of invasive breast cancer in the Western countries. The present study was designed to assess the clinical characteristics and outcomes of ILC compared to general invasive ductal carcinoma (IDC) and the luminal A subtype (LA-IDC).

Methods The study population included d 2916 patients with invasive breast cancer consecutively diagnosed at the National Cancer Center, Korea between 2001 and 2008. The clinicopathological characteristics and clinical outcomes were retrospectively reviewed.

Results There were 83 pts (2.8%) diagnosed with ILC and 1,088 pts (37.3%) with LA-IDC. Mean age was 48.2 years of all patients, 48.3 years of ILC group and 47.9 years of LA-IDC group. The ILC patients presented with a larger tumor size (≥T2, 59.8% vs. 38.8%, P=0.001), lower histologic grade (HG 1 or 2, 90.4% vs 64.4%, P&lt;0.001), more often estrogen receptor (ER) and progesterone receptor (PgR) positivity (ER+, 90.4% vs. 64.4%, P&lt;0.001; PgR+, 71.1% vs. 50.1%, P&lt;0.001), HER2 negativity (97.5% vs. 74.9%, P&lt;0.001), lower Ki-67 expression (10.3% ± 10.6% vs. 20.6% ± 19.8%, P&lt;0.001), and luminal A subtypes (91.4% vs. 51.2%, P&lt;0.001) compared to the IDC group. Six (7.2%) ILC patients and 359 (12.7%) IDC patients developed disease recurrence with a median follow-up of 56.4 months (range 4.9-136.6 months). Although ILC showed similar prognosis to IDC in general (5-year DFS rate, 91.7% in ILC vs. 87.4% in IDC, P=0.31; 5-year OS rate, 93.6% in ILC vs. 92.5% in IDC, P=0.38), its outcome was closer to LA-IDC, and better than non LA-IDC (LA-IDC (ref); ILC, HR 0.77 in recurrence, 95% CI 0.31-1.90, P=0.57; HR 0.75 in death, 95% CI 0.18-3.09, P=0.70; non LA-IDC, HR 1.69 in recurrence, 95% CI 1.23-2.33, P=0.001; HR 1.50 in death, 95% CI 0.97-2.33, P=0.07) in univariate and multivariate analysis.

Conclusions ILC is a very rare histologic subtype of breast cancer in Korea compared to the Western countries and has distinctive clinicopathological characteristics similar to those of LA-IDC. Acknowledgement: supported by NCC grant #0910320

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-09-14.

Synthesis of flavonoids and their effects on aldose reductase and sorbitol accumulation in streptozotocin-induced diabetic rat tissues

Aldose reductase, the key enzyme of the polyol pathway, and oxidative stress are known to play important roles in the complications of diabetes. A drug with potent inhibition of aldose reductase and oxidative stress, therefore, would be a most promising drug for the prevention of diabetic complications. The purpose of this study was to develop new compounds with these dual-effects through synthesis of chalcone derivatives and by examining the structure-activity relationships on the inhibition of rat lens aldose reductase as well as on antioxidant effects. A series of 35 flavonoid derivatives were synthesized by Winget's condensation, oxidation, and reduction of appropriate acetophenones with appropriate benzaldehydes. The inhibitory activity of these derivatives on rat lens aldose reductase and their antioxidant effects, measured using Cu2+ chelation and radical scavenging activities on 1,1-diphenyl-picrylhydrazyl in-vitro, were evaluated. Their effect on sorbitol accumulation in the red blood cells, lenses and sciatic nerves of streptozotocin-induced diabetic rats was also estimated. Among the new flavonoid derivatives synthesized, those with the 2′,4′-dihydroxyl groups in the A ring such as 2,4,2′,4′-tetrahydroxychalcone (22), 2,2′,4′-trihydroxychalcone (11), 2′,4′-dihydroxy-2,4-dimethylchalcone (21) and 3,4,2′,4′-tetrahydroxychalcone (18) were found to possess the highest rat lens aldose reductase inhibitory activity in-vitro, their IC50 values (concentration of inhibitors giving 50% inhibition of enzyme activity) being 1.6 times 10−7, 3.8 times 10−7, 4.0 times 10−7 and 4.6 times 10−7 M, respectively. All of the chalcones tested except 3, 18, 23 with o-dihydroxy or hydroquinone moiety showed a weak free radical scavenging activity. In the in-vivo experiments, however, compound 18 with o-dihydroxy moiety in the B ring showed the strongest inhibitory activity in the accumulation of sorbitol in the tissues. It also showed the strongest activity in transition metal chelation and free radical scavenging activity. Of the 35 4,2′-dihydroxyl and 2′,4′-dihydroxyl derivatives of flavonoid synthesized, including chalcone, flavone, flavanone, flavonol and dihydrochalcone, some chalcone derivatives synthesized were found to possess aldose reductase inhibition and antioxidant activities in-vitro as well as inhibition in the accumulation of sorbitol in the tissues in-vivo. 3,4,2′,4′-Tetrahydroxychalcone (18, butein) was the most promising compound for the prevention or treatment of diabetic complications.

Trastuzumab treatment beyond brain progression in HER2-positive metastatic breast cancer

BACKGROUND

Although trastuzumab therapy improves survival in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer, 40% of patients develop brain metastasis (BM) even when extracranial disease is under control. We studied whether trastuzumab therapy beyond or after BM was beneficial to patients with BM.

PATIENTS AND METHODS

The effect of trastuzumab on survival after BM was analyzed in 78 HER2-positive breast cancer patients. Patients were grouped according to trastuzumab therapy; no treatment and treatment before and after BM were diagnosed.

RESULTS

Overall survival after the diagnosis of BM as well as time to progression (TTP) of intracranial tumors was prolonged in patients who received trastuzumab after BM was diagnosed. Conversely, BM occurred much later in patients who received trastuzumab before BM. In the multivariate Cox regression model, age at BM <50 years, disease-free interval >or=24 months, TTP of intracranial tumor >or=4.8 months, and trastuzumab treatment after BM were significantly associated with longer survival after the onset of BM.

CONCLUSIONS

Trastuzumab therapy after the onset of BM in HER2-positive breast cancer patients is associated with a significant survival benefit after BM diagnosis compared with patients who never received or completed trastuzumab before the BM diagnosis.

Tunneling anisotropic magnetoresistance in multilayer-(Co/Pt)/AlO_(x)/Pt structures

We report observations of tunneling anisotropic magnetoresitance (TAMR) in vertical tunnel devices with a ferromagnetic multilayer-(Co/Pt) electrode and a nonmagnetic Pt counterelectrode separated by an AlOx barrier. In stacks with the ferromagnetic electrode terminated by a Co film the TAMR magnitude saturates at 0.15% beyond which it shows only weak dependence on the magnetic field strength, bias voltage, and temperature. For ferromagnetic electrodes terminated by two monolayers of Pt we observe order(s) of magnitude enhancement of the TAMR and a strong dependence on field, temperature and bias. The discussion of experiments is based on relativistic ab initio calculations of magnetization orientation dependent densities of states of Co and Co/Pt model systems.

The clinical values of squamous cell carcinoma antigen and carcinoembryonic antigen in patients with cervical cancer treated with concurrent chemoradiotherapy

The objective of this study was to determine the prognostic significance of the pre- and posttreatment serum levels of the squamous cell carcinoma antigen (SCC-Ag) and carcinoembryonic antigen (CEA). From 2001 to 2005, 211 patients were treated with concurrent chemoradiotherapy (CCRT). The SCC-Ag and CEA levels were measured before treatment, 1 month after treatment, and during the follow-up. The association between the pretreatment tumor marker levels and the clinical prognostic factors was evaluated. The frequency of complete remission (CR) and the normalization of the posttreatment tumor marker were also analyzed. The pretreatment serum levels of CEA and SCC-Ag were elevated in 68 (32.2%) and 148 (70.1%) patients, respectively. The number of patients with an elevated pretreatment SCC-Ag level was associated with the FIGO stage, tumor volume, and pelvic lymph node status. The pretreatment CEA was only significantly related to the tumor volume and pelvic lymph node involvement. One month after completing CCRT, the CEA and SCC-Ag levels were normalized in almost all patients with an incidence of 88.2% (60/68) and 93.2% (138/148), respectively. Among the patients who gained CR with a previously elevated pretreatment CEA and SCC-Ag, the values were normalized in 92.1% (58/63) and 96.4% (134/139) at 1 month, respectively. Combination assays of the pre- and posttreatment serum CEA and SCC-Ag levels appear to be useful for both predicting the prognosis and estimating the clinical response in cervical cancer. However, the routine combined measurement with SCC-Ag of CEA in all patients had limited additional effect in predicting the prognostic significance.

Kondo effect in magnetic tunnel junctions

Tunneling magnetoresistance was found to be suppressed with decreasing temperature for magnetic tunnel junctions (MTJs) oxidized under high plasma power. A strong temperature dependence of the junction resistance was observed, along with zero-bias anomalies of dynamic resistance at low temperatures. Resistance shows a logarithmic dependence on temperature, and resistance versus temperature exhibits a scaling behavior. Our experimental data can be explained in a consistent way by the Kondo effect in the MTJs with the Kondo temperature TK=20-30 K.