P980Post-procedural plasma brain natriuretic peptide level early after catheter ablation predicts the future clinical outcome in patients with persistent atrial fibrillation and reduced ejection fraction

Background

Successful restoration of sinus rhythm (SR) by catheter ablation (CA) for persistent atrial fibrillation (AF) improves cardiac function, resulting in decrease of plasma brain natriuretic peptide (BNP) level. The exact significance and prognostic implications of this change have yet to be determined.

Purpose

To examine the impact of pre- and post-procedural BNP level on the clinical outcome after CA in patients with persistent AF and reduced left ventricular ejection fraction (LVEF).

Methods

Out of 242 patients with LVEF <50% who underwent first-time CA for persistent AF between March 2012 and September 2018 at our institute, we enrolled 137 patients (61±10 years, 83% male) whose plasma BNP level was available both at baseline and early after CA (during 1–3 month). We evaluated the impact of the BNP levels on future AF recurrence 3 months after CA as the primary endpoint. Additional secondary endpoints included heart failure (HF) hospitalization and cardiovascular death.

Results

All patients successfully restored SR at the end of CA. Within 3 months of a blanking period (BP), improvement of LVEF (from 39±10% to 65±12%, p<0.001) and reduction of BNP levels (from 178 [107–332] pg/ml to 42.3 [21.1–78.6] pg/ml, p<0.001) were observed. During the median follow-up of 21 months after BP, the incidence of AF recurrence, HF hospitalization, and cardiovascular death was 37% (n=50), 3% (n=4), and 1% (n=1), respectively. Cox proportional hazard regression analysis after adjustment for age and gender revealed that post-procedural BNP level was a significant predictor of the AF recurrence (hazard ratio [HR] per 100-pg/ml increase, 1.13; 95% confidence interval [CI], 1.02–1.25; p=0.023), but pre-procedural BNP level was not (1.02; 0.95–1.09; p=0.56). Receiver operating curve analysis determined the post-procedural BNP level of 55.5 pg/ml as the best cut-off value for predicting the AF recurrence, with area under the curve of 0.620 (95% CI, 0.534–0.702; p=0.018). The incidence of AF recurrence was significantly higher in patients with post-procedural BNP level >55.5 pg/ml (n=50) than the others (50% vs. 29%; HR, 3.99; 95% CI, 2.07–7.68; p<0.001). No patients with post-procedural BNP level ≤55.5 pg/ml experienced HF hospitalization and cardiovascular death (8% vs. 0% and 2% vs. 0%, p=0.006 and p=0.17, respectively)

Conclusions

Not pre-procedural but post-procedural BNP level early after CA predicted the future clinical outcome in patients with persistent AF and reduced LVEF. Decreased but still elevated BNP level after restoration of SR would identify the residual risk for developing unfavorable outcome.

P14.01 Differential diagnosis of IDH mutant/IDH wildtype of glioma by using 11C-methionine, 11C-choline, and18F-fluorodeoxyglucose positron emission tomography

BACKGROUND

Positron emission tomography (PET) is important in noninvasive diagnostic imaging of gliomas. There are many PET studies on glioma diagnosis based on the 2007 World Health Organization (WHO) classification; however, there are no studies on glioma diagnosis using the new classification (the 2016 WHO classification).Here we investigated the relationship between PET imaging using 11C-methionine (MET), 11C-choline (CHO), and 18F-fluorodeoxyglucose (FDG) and wildtype isocitrate dehydrogenase (IDH) (IDH-wt)/mutant IDH (IDH-mut) in astrocytic and oligodendroglial tumors according to the 2016 WHO classification.

MATERIAL AND METHODS

In total, 105 patients with newly diagnosed cerebral gliomas (six diffuse astrocytomas [DAs] with IDH-wt, six DAs with IDH-mut, seven anaplastic astrocytomas [AAs] with IDH-wt, 24 AAs with IDH-mut, 26 glioblastomas [GBMs] with IDH-wt, five GBMs with IDH-mut, 19 oligodendrogliomas [ODs], and 12 anaplastic oligodendrogliomas [AOs]) were included. All OD and AO patients had both IDH-mut and 1p/19q codeletion. The maximum standardized uptake values (SUVs) of the tumor/normal cortex mean SUV ratios (T/N ratios) for MET, CHO, and FDG were calculated; the mean T/N ratios of DA, AA, and GBM with IDH-wt/IDH-mut were compared. The diagnostic accuracy for distinguishing gliomas with IDH-wt from those with IDH-mut was assessed using receiver operating characteristic (ROC) curve analysis of the mean T/N ratios for the three PET tracers.

RESULTS

There were significant differences in the mean T/N ratios for all three PET tracers between the IDH-wt and IDH-mut groups including all histological classifications (p<0.001). Among the 27 gliomas with mean T/N ratios higher than the cutoff values for all three PET tracers, 23 (85.2%) were classified into the IDH-wt group using ROC analysis. In DA, there were no significant differences in the T/N ratios for MET, CHO, and FDG between the IDH-wt and IDH-mut groups. In AA, the mean T/N ratios of all three PET tracers in the IDH-wt group were significantly higher than those in the IDH-mut group (p<0.001). In GBM, the mean T/N ratio in the IDH-wt group was significantly higher than that of the IDH-mut group for both MET (p=0.034) and CHO (p=0.01). However, there was no significant difference in the ratio for FDG.

CONCLUSIONS

PET imaging using MET, CHO, and FDG was confirmed to be informative for preoperatively differentiating gliomas according to the 2016 WHO classification, particularly for differentiating IDH-wt and IDH-mut tumors.

Oral environment and taste function of Japanese HIV-infected patients treated with antiretroviral therapy

The aim of the study was to evaluate the oral environment and the taste function of Japanese HIV-infected patients treated with antiretroviral therapy. Their median age of 73 patients taking anti-HIV drugs was 46 years. The median period of taking anti-HIV drugs was 30 months. The oral condition was evaluated by measurement of oral moisture, amount of saliva secretion, the number of oral bacteria, presence of oral candida, a taste test, and the number of missing teeth. The levels of oral moisture and secreted saliva were significantly lower in the HIV-infected group than in the healthy volunteer (control) group. The HIV-infected group showed a more robust decrease in taste sensation than the control group. The number of missing teeth was significantly higher in the HIV-infected group than in the control group. Furthermore, all of the evaluated oral conditions were worse in the HIV-infected patients whose CD4+ T lymphocyte counts were less than 500/mm³ than in the control group. It became clear that the patients taking anti-HIV drugs, especially the CD4+ count < 500/mm3 group, had a deteriorated oral environment and dysgeusia, suggesting that the management of oral hygiene is necessary to maintain oral health, which leads to systemic health.

The geomorphology, color, and thermal properties of Ryugu: Implications for parent-body processes

The near-Earth carbonaceous asteroid 162173 Ryugu is thought to have been produced from a parent body that contained water ice and organic molecules. The Hayabusa2 spacecraft has obtained global multicolor images of Ryugu. Geomorphological features present include a circum-equatorial ridge, east-west dichotomy, high boulder abundances across the entire surface, and impact craters. Age estimates from the craters indicate a resurfacing age of [Formula: see text] years for the top 1-meter layer. Ryugu is among the darkest known bodies in the Solar System. The high abundance and spectral properties of boulders are consistent with moderately dehydrated materials, analogous to thermally metamorphosed meteorites found on Earth. The general uniformity in color across Ryugu's surface supports partial dehydration due to internal heating of the asteroid's parent body.

Abstract P6-02-11: The TILs-US scores based on ultrasonography can predict lymphocyte-predominant breast cancer before surgery

[Purpose]

Tumor-infiltrating lymphocytes (TILs) has been shown to be useful for predicting outcomes after surgery in breast cancer, and while TILs can be evaluated in preoperative biopsy tissue, heterogeneous distribution of TILs requires examination of all biopsied tissue samples.

We gave scores to preoperative ultrasonography (US) images with characteristics indicative of lymphocyte-predominant breast cancer (LPBC) and attempted to apply these for diagnostic prediction of LPBC. In this study, TILs-US scores based on preoperative US were assessed for their usefulness in predicting LPBC, the diagnosis of which was confirmed with postoperative pathology.

[Methods]

We evaluated 161 patients with invasive breast cancer between January 2014 and December 2017. All patients were treated by either mastectomy or breast-conserving surgery. Stromal lymphocytes were evaluated on preoperative biopsy tissues and surgical pathological specimens. Breast cancer samples with ≥ 50% stromal TILs were defined as pre-LPBC (preoperative biopsy tissues) and LPBC (surgical pathological specimens). TILs-US score was calculated from US before curative surgery. Based on clinicopathological factors including TILs-US scores based on preoperative US and pre-LPBC indicators, determinants useful for prediction of LPBC were examined.

[Results]

There were 39 cases of LPBCs and 122 cases of non-LPBCs in surgical pathological specimens. We set TILs-US score cut-offs for predicting LPBC at 4 points based on the receiver operating characteristics (ROC) curves (AUC, 0.88). There were significant predictors for LPBC in maltivariate logistic analysis (TILs-US score: OR26.8, p&lt;0.001; pre- LPBC: 18.6, p=0.002; HER-2: OR9.2, p=0.009) in preoperative clinicopathological factor. The sensitivity, specificity and accuracy of TILs-US score for predicting LPBC were 0.74 (0.62-0.84), 0.89 (0.85-0.92) and 0.85 (0.79-0.90). Those of pre-LPBC were 0.51(0.42-0.55), 0.98 (0.96-1.00) and 0.87 (0.82-0.89), and those of HER2 were 0.28(0.19-0.36), 0.94(0.91-0.97) and 0.78 (0.74-0.82), respectively. The sensitivity of TILs-US score for predicting LPBC was significantly greater than those of pre- LPBC (p=0.04) and HER2 (p&lt;0.001). On the other hand, the specificity of pre- LPBC for predicting LPBC was significantly greater than that of TILs-US score(p=0.002).

The sensitivity, specificity and accuracy of predicting LPBCPerformance measureTILs-US score (95%CI)Preoperative biopsyHER-2P, TILs-US score vs. Preoperative biopsyP, TILs-USscore vs. HER-2Sensitivity0.74 (0.62-0.84)0.51 (0.42-0.55)0.28 (0.19-0.36)0.04&lt;0.001Specificity0.89 (0.85-0.92)0.98 (0.96-1.00)0.94 (0.91-0.97)0.0020.11Accuracy0.85 (0.79-0.90)0.87 (0.82-0.89)0.78 (0.74-0.82)0.230.11

[Conclusions]

TILs-US scores are an important factor that can predict LPBC preoperatively. The TILs-US score has particularly high sensitivity and may be an applicable index in the preoperative evaluation for LPBC.

Citation Format: Kanou A, Masumoto N, Shiroma N, Fukui K, Sasada S, Emi A, Kadoya T, Yokozaki M, Arihiro K, Okada M. The TILs-US scores based on ultrasonography can predict lymphocyte-predominant breast cancer before surgery [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 P6-02-11.

Abstract P6-02-06: Characteristics of lymphocyte-predominant breast cancer in ultrasound images and their application to diagnostic prediction

[Purpose]

Tumor-infiltrating lymphocytes (TILs) is a prognostic factor for breast cancer, however, an accurate and simple evaluation method remains elusive. Therefore, we focused on findings characteristic of lymphocyte-predominant breast cancer (LPBC) in ultrasound (US) images. In this study, the application of preoperative US image assessment to diagnostic prediction of LPBC evaluated from postoperative pathological specimens, was appraised.

[Methods]

We evaluated 191 patients with invasive breast cancer between January 2014 and December 2017. All patients were treated by either mastectomy or breast-conserving surgery. Stromal lymphocytes were evaluated on surgical pathological specimens. Breast cancer samples with ≥ 50% stromal TILs were defined as LPBC. Preoperative US was performed in all cases and images were examined for characteristics indicative of TILs. Scores were given to US images with characteristic TILs and these TILs-US scores were assessed for their application to predict LPBC.

[Results]

There were 39 cases of LPBCs and 122 cases of non-LPBCs in surgical pathological specimens.

The characteristic US image findings predicting LPBC were shape (more lobulated), internal echo level (weaker) and posterior echoes (stronger). The TILs-US scores were given based on these three ultrasound tissue characterizations.We set TILs-US score cut-offs for predicting LPBC at 4 points (Sensitivity, 0.73; specificity, 0.87; accuracy, 0.83) based on the receiver operating characteristics (ROC) curves (AUC, 0.88). There were significant predictors for LPBC in maltivariate logistic analysis (Nuclear Grade (NG): OR3.4, p=0.02; ER: 5.7, p =0.007;HER-2: OR4.1, p=0.04; TILs-US score2: OR14.9, p&lt;0.001) in preoperative clinicopathological factor. The sensitivity, specificity and accuracy of NG for predicting LPBC were 0.75, 0.69 and 0.71. Those of ER and HER2 were 0.33, 0.96 and 0.79.Sensitivity, specificity, and accuracy of NG, ER, and HER2 diagnoses were all lower than the TILs-US score, and the TILs-US score showed the best diagnostic ability.

The sensitivity, specificity and accuracy of predicting LPBCPerformance measureTILs-US score (95%CI)NGER or HER-2P, TILs-US score vs. NG,P, TILs-USscore vs. ER or HER-2Sensitivity0.73 (0.63-0.81)0.75 (0.64-0.84)0.327 (0.24-0.39)0.08&lt;0.001specificity0.87 (0.83-0.90)0.69 (0.65-0.72)0.957 (0.93-0.98)&lt;0.001&lt;0.001accuracy0.83 (0.77-0.88)0.707 (0.65-0.376)0.785 (0.74-0.82)0.0040.25

Conclusions

LPBC has characteristic ultrasound tissue characterizations in US images. Thus, TILs-US scores based on US may be applicable to accurate and convenient preoperative diagnosis of LPBC.

Citation Format: Fukui K, Masumoto N, Shiroma N, Kanou A, Yokozaki M, Sasada S, Emi A, Kadoya T, Arihiro K, Okada M. Characteristics of lymphocyte-predominant breast cancer in ultrasound images and their application to diagnostic prediction [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 P6-02-06.

Abstract P6-02-09: Diagnostic performance of dedicated breast PET for the prediction of pathological response after neoadjuvant chemotherapy

Background: Neoadjuvant chemotherapy (NAC) is a standard treatment for operable breast cancer. However, imaging methods for evaluating treatment response have not been established. Previous studies reported that ring-type dedicated breast positron emission tomography (DbPET) detected residual tumors following NAC more accurately than whole-body PET/CT. This study assessed DbPET parameters for predicting pathological complete response (pCR) in patients with breast cancer.

Patients and Methods: Among patients with breast cancer who underwent surgery after NAC, 61 were examined using ring-type DbPET before and after NAC. The maximum standardized uptake values (SUVmax) and tumor-to-normal-tissue ratio (TNR) were calculated before and after NAC (pre-SUVmax, pre-TNR, post-SUVmax and post-TNR, respectively). Moreover, the reduction rates (ΔSUVmax and ΔTNR) were determined. pCR was defined as complete remission of breast cancer.

Results: The median patient age was 52 years. Forty patients (65.6%) were estrogen receptor (ER)-positive, whereas 25 patients (41.0%) were HER2-positive. Fifteen patients (24.6%) achieved pCR after NAC. The calculated values for the parameters of DbPET are summarized in Table 1. The most promising parameters for predicting pCR were ΔSUVmax (area under the curve [AUC]: 0.506) and post-TNR (AUC: 0.640). Although neither of these two parameters reflected the pathological response to NAC in patients with ER-positive disease, post-TNR showed the highest AUC (i.e., AUC: 0.750) for pCR in patients with ER-negative disease. The sensitivity and specificity of post-TNR in the ER-positive group were 85.7% and 39.4%, respectively. In the ER-negative group, these values were 100% and 58.3%, respectively [Table 2]

Table 1.Diagnostic performance of dedicated breast positron-emission tomography for the prediction of pathological complete response after neoadjuvant chemotherapyParameterspCR Median (IQR)Non-pCR Median (IQR)PAUC (95% CI)Pre-SUVmax14.8 (9.2–17.7)14.4 (10.7–19.8)0.6040.454 (0.285–0.624)Post-SUVmax1.8(1.5–2.1)2.0 (1.6–3.4)0.2370.603 (0.460–0.746)ΔSUVmax (%)87.32 (81.5–91.8)88.6(82.8–91.8)0.9540.506 (0.329–0.682)Pre-TNR8.0 (5.3–9.2)7.3(5.9–10.2)0.7570.472 (0.297–0.647)Post-TNR1.7(1.0–1.1)1.2 (1.0–2.4)0.0980.640 (0.506–0.774)ΔTNR (%)87.3 (78.3–89.1)79.8 (62.7–86.7)0.1130.638 (0.472–0.803)pCR, pathological complete response; IQR, interquartile range; AUC, area under the curve; CI, confidence interval, SUV, standardized uptake value; TNR, tumor-to-normal-tissue ratio.Table 2.Diagnostic accuracy of post-TNR according to estrogen receptor status Sensitivity (%)Specificity (%)Accuracy (%)PPV (%)NPV (%)ER-positive85.739.447.523.192.9ER-negative10058.375.061.5100TNR, tumor-to-normal-tissue ratio; ER, estrogen receptor; PPV, positive predictive value; NPV, negative predictive value

Conclusion: In DbPET, ΔSUVmax and post-TNR were shown to be promising parameters for predicting pathological response to NAC. Post-TNR provided the highest sensitivity for predicting pCR in patients with ER-negative breast cancer.

Citation Format: Suzuki E, Sasada S, Sueoka S, Masumoto N, Goda N, Kajitani K, Emi A, Haruta R, Kadoya T, Kataoka T, Okada M. Diagnostic performance of dedicated breast PET for the prediction of pathological response after neoadjuvant chemotherapy [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 P6-02-09.

Abstract P6-02-17: Hand-held impulse-radar detector for breast cancer: development and a pilot study

Background: Microwave breast imaging, which using the difference in the dielectric properties between breast cancer and normal breast tissue, is a painless and non-radiation method. We have created a novel hand-held prototype of breast cancer detector using impulse-radar based imaging system, and conducted a pilot clinical study.

Methods: The detector consists of complementary metal-oxide-semiconductor (CMOS) integrated circuits covering the ultrawideband width from 3.1 to 10.6 GHz, which enable the generation and transmission of Gaussian monocycle pulse (GMP) trains and single port eight throw switching matrices (SP8T-SW) for controlling a 4×4 cross-shaped dome antenna array. The size of the detector was 19.1 × 17.7 × 18.8 cm. After evaluation using a breast tumor phantom and the resected breast specimens obtained through mastectomy, we recruited 5 patients with histologically confirmed breast cancers in the clinical study. The detector was placed on the breast with the patient in a supine position. The primary endpoint was a detection rate of breast cancers, and the secondary endpoints were positional accuracy and adverse event. This study was registered with the UMIN Clinical Trials Registry (UMIN000026181).

Results: The three-dimensional positions of the tumors in the imaging results using a phantom and resected specimens are consistent with the results of histopathology analysis. In the clinical study, all 5 targeted breast cancers were detected and were visualized at the sites confirmed by other diagnostic modalities. Among 5 tumors, one was not detected via mammography because of heterogeneously dense breast and another was a microinvasive carcinoma of invasive tumor size 0.5 mm. No study-related adverse events occurred.

Conclusions: We succeeded in creating a new device of hand-held impulse-radar detector for breast cancer. The detector has sufficient detective capability, is safe for clinical use, and might detect an early stage breast cancer. In the future, we will proceed with the development to clinical application.

Citation Format: Sasada S, Masumoto N, Song H, Goda N, Kajitani K, Emi A, Kadoya T, Arihiro K, Kikkawa T, Okada M. Hand-held impulse-radar detector for breast cancer: development and a pilot study [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 P6-02-17.

Blister-based-laser-induced-forward-transfer: a non-contact, dry laser-based transfer method for nanomaterials

We show that blister-based-laser-induced forward-transfer can be used to cleanly desorb and transfer nano- and micro-scale particles between substrates without exposing the particles to the laser radiation or to any chemical treatment that could damage the intrinsic electronic and optical properties of the materials. The technique uses laser pulses to induce the rapid formation of a blister on a thin metal layer deposited on glass via ablation at the metal/glass interface. Femtosecond laser pulses are advantageous for forming beams of molecules or small nanoparticles with well-defined velocity and narrow angular distributions. Both fs and ns laser pulses can be used to cleanly transfer larger nanoparticles including relatively fragile monolayer 2D transition metal dichalcogenide crystals and for direct transfer of nanoparticles from chemical vapour deposition growth substrates, although the mechanisms for inducing blister formation are different.

Efficacy and Safety of Subcutaneous Belimumab in Anti-Double-Stranded DNA-Positive, Hypocomplementemic Patients With Systemic Lupus Erythematosus

OBJECTIVE

To investigate the efficacy and safety of belimumab, a human immunoglobulin monoclonal antibody against B lymphocyte stimulator, in a subset of patients with systemic lupus erythematosus (SLE) who were hypocomplementemic (C3 <90 mg/dl and/or C4 <10 mg/dl) and anti-double-stranded DNA (anti-dsDNA) positive (≥30 IU/ml) at baseline.

METHODS

In this phase III, double-blind, placebo-controlled study (BEL112341; ClinicalTrials.gov identifier: NCT01484496), patients with moderate to severe SLE (Safety of Estrogens in Lupus Erythematosus National Assessment version of the Systemic Lupus Erythematosus Disease Activity Index [SELENA-SLEDAI] score ≥8) were randomized (2:1) to receive weekly subcutaneous (SC) belimumab 200 mg or placebo, plus standard SLE therapy, for 52 weeks. The primary end point was SLE Responder Index 4 (SRI-4) response rate at week 52. Secondary end points were time to severe flare and reduction in corticosteroid dose (weeks 40-52). Safety was assessed throughout.

RESULTS

Of the 836 patients in the intent-to-treat (ITT) population, 356 were hypocomplementemic and anti-dsDNA positive at baseline (108 in the placebo group and 248 in the SC belimumab 200 mg group). Compared with placebo, the belimumab group contained more SRI-4 responders (47.2% versus 64.6%; P = 0.0014), had a lower incidence of severe flare according to the SELENA-SLEDAI flare index (31.5% versus 14.1%), and had a greater percentage of patients who reduced corticosteroid dosage by ≥25% to ≤7.5 mg/day during weeks 40-52 (11.4% versus 20.7%; P = 0.0844). Adverse events (AEs) were similar between treatment groups.

CONCLUSION

Our findings indicate that in hypocomplementemic, anti-dsDNA-positive SLE patients, weekly SC belimumab 200 mg significantly improves SRI-4 response, decreases severe flare incidence, and reduces corticosteroid use versus placebo; a trend toward greater benefit compared with the overall ITT population was observed. AEs were consistent with the known safety profile of belimumab.

Abstract P5-02-03: Evaluation of pathological malignancy grade and neoplastic progress of breast cancer using dedicated breast positron emission tomography

Background: Dedicated breast positron emission tomography (DbPET)provides detailed high resolution images of the breast and enables quantitative assessment using standard uptake values (SUVs). We aimed to determine whether DbPET can predict the pathological malignancy grade and neoplastic progress of breast cancer compared with whole body (WB) PET.

Methods: We investigated 196 consecutive patients with invasive breast cancerwho underwent concurrent Db- and WB-PET from January 2016 to March 2017. All Db- and WB-PET were quantified based on SUVs. We also investigated pathological features of breast cancer who had a ring-like uptake (RU) without central FDG accumulation on DbPET.

Results:

The associations between the SUVs for DB- and WB-PET and the pathological factors in breast cancerCharacteristicSUV WBPETDbPET Mean ± SDpMean ± SDpall3.6 ± 3.4 9.4±7.9 Tumor size    ≤2.0 cm2.2±1.6&lt;0.0016.5±5.2&lt;0.001&gt;2.0 cm5.5±4.1 13.3±9.2 LN    Negative3.1±3.3&lt;0.0018.4±7.8&lt;0.001Positive4.9±3.2 11.8±7.7 NG    1 or 22.4±2.1&lt;0.0016.6±5.9&lt;0.00135.1±4.0 12.7±8.7 Ki67    &lt; 201.8±1.1&lt;0.0015.2±3.3&lt;0.001≥ 204.4±3.7 11.4±8.6 ER    positive3.4±3.30.028.8±7.60.006negative5.2±3.6 13.5±8.6 HER-2    positive4.6±3.10.0911.8±7.60.04negative3.4±3.4 9.0±7.9 Sub type vs Lumnal A vs Lumnal ALuminal A1.8±1.1 5.2±3.3 Luminal B4.0±3.8&lt;0.00110.1±8.5&lt;0.001HER24.6±3.1&lt;0.00111.8±7.6&lt;0.001Triple negative5.3±3.8&lt;0.00113.8±9.2&lt;0.001

summarizes the association between SUVs for Db- and WB-PET and pathological factors inbreast cancer.SUVs on PET were significantly higher for the tumor size of &gt;2.0 cm than for tumor size ≤2.0 cm (p&lt;0.001), for LN-positive than for LN-negative (p&lt;0.001), for NG3 than for NG1-NG2 (p&lt;0.001), for higher Ki67 expression than for lower Ki67 expression (p&lt;0.001), and for ER-negative than for ER-positive (WBPET, p=0.02; DbPET, p=0.006). SUVs were significantly lower for Luminal A than for Luminal B, HER2, and triple-negative cancer (p&lt;0.001 for all three).SUVs for DbPET was significantly higher for HER2-positive than for HER2-negative (p=0.02).

The association between SUVs for breast cancer with and without RU on DbPETCharacteristicRU(-), nRU(+), npall17323 Tumor size   ≤2.0 cm1095&lt;0.001&gt;2.0 cm6418 LN   Negative1299&lt;0.001Positive4414 NG   1 or 210070.0237316 Ki67   &lt; 206130.03≥ 2011220 ER   positive152190.49negative214 HER-2   positive2620.38negative14721 Sub type  vs Lumnal ALuminal A493 Luminal B84150.02HER22620.81Triple negative1430.04

summarizes the association between SUVs for breast cancer with and without RU on DbPET. SUVs for breast cancer with RU on DbPET were significantly higher for the tumor size of &gt;2.0 cm than for tumor size ≤2.0 cm, for LN -positive than for LN-negative (p&lt;0.001), for NG3 than for NG1-2 (p=0.02), and for higher Ki67 expression than for lowerKi67 expression (p=0.03). SUVs were significantly lower for Luminal A than for Luminal B (p=0.02) and triple-negative cancer (p=0.04).

Conclusions: SUVs for DbPET were equal or superiorto WBPET in predicting the pathological malignancy grade and neoplastic progress in tumors. Furthermore, the presence of RU on DbPET can provide excellent predictive value for high-grade malignancy and might help to determine appropriate therapeutic strategies.

Citation Format: Masumoto N, Kadoya T, Nishina M, Kimura Y, Suzuki E, Sueoka S, Goda N, Sasada S, Kajitani K, Emi A, Haruta R, Kataoka T, Okada M. Evaluation of pathological malignancy grade and neoplastic progress of breast cancer using dedicated breast positron emission tomography [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-02-03.

Abstract P6-03-08: Detection ability of dedicated breast positron emission tomography for small-sized breast cancer

Background: Whole body (WB) 18F-fluorodeoxyglucose positron emission tomography (PET) has a relatively poor spatial resolution (&gt;1 cm), which limits the capability to detect small lesions. Therefore, small-sized breast cancers (≤1 cm) may not be visible on WBPET. To overcome these limitations, dedicated breast PET (DbPET) has been developed to improve spatial resolution. DbPET enables detailed high-resolution images within the breast. We aimed to determine whether DbPET can detect small-sized breast cancer compared to WBPET.

Methods: We investigated 203 consecutive patients (217 tumors) (T1–3, N0–3a, M0) with breast cancer who underwent concurrent DbPET and WBPET between January 2016 and March 2017. All DbPET and WBPET images were semi-quantified based on standard uptake values. The diagnostic performance of each scanner was assessed in DbPET and WBPET. Tumors were classified based on pathological classification as follows: Tis, ductal carcinoma in situ (DCIS); T1a, ≤0.5 cm; T1b, 0.5–1 cm; and T1c, 1–2 cm; T2, 2–5 cm; T3, &gt;5 cm. The sensitivities of DbPET and WBPET were compared in each size group.

Results: Table 1 shows the detection rate of breast cancer in WBPET and DbPET

The detection rate of breast cancer in WB- and Db-PET DbPETWBPETpTumor sizeDetection (-) n(%)Detection (+) n(%)Detection (-) n(%)Detection (+) n(%) Tis6(14.6)35(85.4)18(43.9)23(56.1)0.0030T1a2(8)23(92)7(28)18(72)0.0594T1b2(6.5)29(93.5)10(32.3)21(67.7)0.0077T1c5(8.2)56(91.8)11(18)50(82)0.1038T20(0)57(100)1(1.8)56(98.2)0.2375T30(0)2(100)0(0)2(100)-total15(6.9)202(93.1)47(21.7)170(78.3)&lt;0.0001

. The overall detection rate in DBPET [93.1% (202/217)] was significantly higher than that of WBPET [78.3% (170/217)] (P &lt; 0.001). For smaller tumors, DbPET was more sensitive than WBPET: Tis (85.4% vs. 56.1%), T1a (92% vs. 72%), T1b (93.5% vs. 67.7%), T1c (91.8% vs. 82%), T2 (100% vs. 98.2%), and T3 (100% vs. 100%). The sensitivity of DbPET was significantly higher than that of WBPET in Tis (P = 0.003) and T1b (P = 0.008) and tended to be higher than that of WBPET in T1a (P = 0.059). Conversely, no significant differences were observed in T1c (P = 0.103) and T2 (P = 0.238).

Conclusion: The imaging sensitivity of DbPET was higher than that of WBPET. DbPET showed significant sensitivity in DCIS and tumors ≤1 cm, which is a weak point for WBPET. DbPET may serve as a new diagnostic modality to detect small-sized breast cancer.

Citation Format: Sueoka S, Masumoto N, Nishina M, Kimura Y, Suzuki E, Goda N, Sasada S, Kajitani K, Emi A, Haruta R, Kadoya T, Kataoka T, Okada M. Detection ability of dedicated breast positron emission tomography for small-sized breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-03-08.

A Modified Method of Activity-based Costing for Objectively Reducing Cost Drivers in Hospitals

Objectives: Activity-based costing (ABC) is widely used to precisely allocate indirect costs to medical services. In the ABC method, the indirect cost is divided among the medical services in proportion to the volume of “cost drivers”, for example, labor hours and the number of hours of surgery. However, the workload of data collection of cost drivers can be time-consuming and a considerable burden if there are many cost drivers. The authors aim to develop a method for objectively reducing the cost drivers used in the ABC method.

Methods: In the ABC method, the cost driver is assigned for each activity. We assume that these activities and cost drivers are the best combination. Our method, that is cost driver reduction (CDR), can objectively select surrogates of the cost drivers for each activity in ABC from candidate cost drivers. Concretely, the total indirect cost of an activity is temporarily allocated to the medical services using each candidate of cost drivers. The difference between the costs calculated by each candidate and the proper cost driver used in ABC is calculated to evaluate the similarity by the evaluation function.

Results: We estimated the cost of laboratory tests using our method and revealed that the number of cost drivers could be reduced from seven in the ABC to four. Similarly, the results of cost estimation obtained by our method were as accurate as those calculated using the ABC.

Conclusions: Our method provides two advantages compared to the ABC method: 1) it provides results that are as accurate as those of the ABC method, and 2) it is simpler to perform complicated estimation of hospital costs.

Efficacy of Eculizumab Therapy for Atypical Hemolytic Uremic Syndrome Recurrence and Antibody-Mediated Rejection Progress After Renal Transplantation With Preformed Donor-Specific Antibodies: Case Report

Atypical hemolytic uremic syndrome (aHUS) develops as the result of unregulated complement progression and precipitates de novo thrombotic microangiopathy. Plasma therapy is used to control the progression of the complement cascade, but that therapy is not effective in all patients and is accompanied by risk of infection and/or allergy. Eculizumab has been reported as an efficient therapy for aHUS. We report the case of a 35-year old woman who underwent effective eculizumab therapy for aHUS recurrence and antibody-mediated rejection (AMR) progress after renal transplantation with preformed donor-specific antibodies (DSA). She developed end-stage renal disease due to suspicious IgA nephropathy at age 33 years. Kidney transplantation was performed at age 35 years, and aHUS recurred 2 weeks later, leading to the progressive hemolytic anemia and renal dysfunction. Therefore, she underwent plasma therapy several times. Because it was difficult to continue to plasma therapy for severe allergy, eculizumab was proposed as an alternate therapy. Treatment with eculizumab was initiated 36 days after renal transplantation. After 3 years of eculizumab treatment, and without plasma therapy, schistocytes decreased, haptoglobin increased to within normal limits, creatinine levels stabilized, and no further episodes of diarrhea were reported. At protocol biopsy 1 year after transplantation, she was diagnosed with C4d-negative subclinical AMR. However, her pathologic findings at follow-up biopsy 3 years after transplantation were recovered. We conclude that eculizumab alone, without plasma therapy, is sufficient to treat recurrence of aHUS and AMR due to DSA after renal transplantation and to maintain long-term graft function.