[Overview of Clinical Application of Whole Genome Analysis for Cancer]

Cancer genomic medicine in Japan began in earnest with the implementation of gene panel testing covered by national health insurance in June 2019. However, the information obtained from this testing is limited to less than 0.1% of the entire genome. To enhance the effectiveness of therapy, understand the intricate biology of cancer, and develop new therapeutic drugs, it has become essential to promote the analysis of the whole genome. In Japan, the Action Plan for Whole Genome Analysis(Version 1)was released in December 2019. In 2021, AMED project"the full-scale operation of cancer whole genome analysis"was launched. The Action Plan for Whole Genome Analysis 2022 set a goal to return the information promptly to patients and citizens. Project Implementation Preparation Office was organized in April 2023 for acceleration of the system development for the clinical whole genome analysis. This paper introduces the current efforts and discuss the future perspectives of cancer genome medicine in Japan.

Prognostic impact of cancer genomic profile testing for advanced or metastatic solid tumors in clinical practice

Cancer genomic profile (CGP) testing, which is covered by the national health insurance system in Japan, has been introduced as a routine clinical practice. However, the effects of CGP testing on prognoses remain unclear. Drug accessibility rates and prognoses after CGP testing were retrospectively investigated in 713 patients who underwent CGP testing examined by our molecular tumor board between November 2019 and October 2022,. Overall survival (OS) was examined using the log-rank test and the Kaplan-Meier method. The median age of patients (326 males and 387 females) was 58 years (12-85 years). CGP testing revealed one or more gene mutations in 681 cases (95.5%), among which actionable gene mutations were detected in 439 (61.6%). Although treatment options were recommended for 285 cases (40.0%) by the molecular tumor board, only 45 received treatment based on their gene mutations. During the median observation period of 8.6 months, 351 (49.2%) patients died of the exacerbation of existing diseases. No significant differences were observed in OS between patients treated with and without genomically matched therapy (p = 0.285). According to clinical responses to treatment based on gene mutations, median OS was significantly longer in patients who achieved partial response and stable disease (26.5 months; 95% CI 14.4-38.6) than in those with progressive disease and not evaluated (9.8 months; 95% CI 5.8-13.8, p = 0.013). Responses to treatment based on gene mutations may improve prognoses, and it is important to increase the drug accessibility rate after CGP testing.

Druggable gene alterations in Japanese patients with rare malignancy

Without a current standard of care, patients with rare malignancy are subjected to precision oncology with next-generation sequencing to identify a course of treatment. We sought to establish the clinical relevance of comprehensive genomic profiling (CGP) among patients with rare malignancy. Rare malignancy was defined using the Rare Cancers in Europe definition (<6 cases per 100,000 individuals). We analyzed gene mutations, fusions, tumor mutational burden (TMB), and microsatellite instability (MSI) status. Level A gene alterations, categorized using Clinical Interpretations of Variants in Cancer and MD Anderson Knowledge Base for Precision Oncology, were considered druggable. Rare malignancy accounted for 149 (45%) cases, with female genital cancers (32%) most common. Among the rare malignancy cases, we identified a lower frequency of mutation in TP53 (41% vs. 60%, P<0.001), KRAS (13% vs. 43%, P<0.001) and APC (3% vs. 25%, P<0.001), and a higher frequency of ARID1A mutation (14% vs. 6%, P=0.03), as compared with common malignancies. TMB-high and MSI-high cases were found in 8% and 2% of cases, respectively. Druggable alterations were detected in 37 patients with rare malignancy; this percentage tended to be higher than that for patients with common malignancies (25% vs. 17%, P=0.08). Common druggable alterations were BRAF V600E, ERBB2 amplification, PIK3CA E542K, and BRCA1/2 variant. Five of the 37 patients with druggable alterations received genome-driven treatment. There was no significant difference in overall survival between the rare and common malignancy groups. Our results provide clues for future clinical development and treatment success among Japanese patients with rare cancers.

Evaluation of an inflammation-based score for identification of appropriate patients for comprehensive genomic profiling

Performance status (PS) is widely used as an assessment of general condition in patients before performing comprehensive genomic profiling (CGP). However, PS scoring is dependent on each physician, and there is no objective and universal indicator to identify appropriate patients for CGP. Overall, 263 patients were scored using the modified Glasgow prognostic score (mGPS) from 0 to 2 based on the combination of serum albumin and c-reactive protein (CRP): 0, albumin ≥ 3.5 g/dl and CRP ≤ 0.5 mg/dl; 1, albumin < 3.5 g/dl or CRP > 0.5 mg/dl; and 2, albumin < 3.5 g/dl and CRP > 0.5 mg/dl. Overall survival was compared between mGPS 0-1 and mGPS 2 groups. The prognosis of patients with PS 0-1 and mGPS 2 was also evaluated. Thirty-nine patients (14.8%) were mGPS 2. Patients with mGPS 2 had significant shorter survival (14.7 months vs 4.6 months, p < 0.01). Twenty-eight patients were PS 0-1 and mGPS 2, and their survival was also short (5.6 months). Evaluation of mGPS is a simple and useful method for identifying patients with adequate prognosis using CGP.

Abstract 5735: Druggable gene alterations in Japanese patients with rare malignancy

Background: In the absence of a current standard of care, precision oncology with next-generation sequencing provides an important therapeutic option for patients with rare malignancy. Here, we sought to establish the clinical relevancy of comprehensive genomic profiling (CGP) for patients with rare malignancy.

Methods: We reviewed 341 patients who underwent CGP (FoundationOne CDx; OncoGuide NCC OncoPanel System)in our institution between 2019 and 2021. Cases were classified as common or rare malignancy based on the Rare Cancers in Europe (RARECARE) definition (incidence of &lt;6 cases per 100,000 individuals). We analyzed the genomic features in the rare malignancy cohort, including gene mutations, gene fusions, tumor mutational burden (TMB), and microsatellite instability (MSI) status. Gene variants, amplifications, and fusions categorized as evidence level A using Clinical Interpretations of Variants in Cancer (CIViC) and MD Anderson Knowledge Base for Precision Oncology were considered as druggable alterations. CGP testing was used to calculate overall survival (OS) to death or at the last follow-up.

Results: With the exception of 7 unclassifiable cases, rare malignancy accounted for 149 of the 334 cases (45%), with the most common being female genital cancers (32%), followed by digestive cancers (24%), sarcoma (16%), and others (28%). Many (83%) of the patients with rare malignancy harbored at least one pathogenic/likely-pathogenic variant. The commonly mutated genes were TP53 (41%), PIK3CA (20%), ARID1A (14%), and KRAS (13%). ERBB2amplification was detected in 6% of patients (median copy number, 8). Gene fusion in EWSR1 was found in 4% of patients (sarcoma) and in FGFR2 in 1% (cholangiocarcinoma and salivary duct carcinoma). TMB-high (≥10 mut/Mb) and MSI-high cases were found in 8% and 2% of cases, respectively. Druggable alterations were detected in 36 patients; this percentage was not significantly different to that of common malignancy (24% vs. 17%, P=0.10). The common druggable alterations were BRAF V600E (n=10), ERBB2 amplification (n=9), PIK3CA E542K (n=6), and BRCA1/2 variant (n=6). There was no significant difference in OS between the rare and common malignancy groups (1-year OS rate: 62% vs. 46%, P=0.24).

Conclusion: In this study, the ratio of rare malignancy was higher than that typically found in previous epidemiological studies (about 20%-25%). We observed no adverse impact for OS, which might be due to the high number of patients (n=48) with intractable pancreatic cancer. Remarkably, &gt;20% of patients harbored a potential druggable alteration. Our results suggest the clinical relevance of CGP for patients with rare malignancy, and its potential utility to provide clues for future clinical development.

Citation Format: Akihiro Ohmoto, Naomi Hayashi, Ippei Fukada, Masumi Yamazaki, Mayu Yunokawa, Akiyoshi Kasuga, Eiji Shinozaki, Arisa Ueki, Akiko Tonooka, Kengo Takeuchi, Seiichi Mori, Kazuma Kiyotani, Shunji Takahashi. Druggable gene alterations in Japanese patients with rare malignancy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5735.

Serial circulating tumor DNA monitoring of CDK4/6 inhibitors response in metastatic breast cancer

Cyclin‐dependent kinase 4/6 inhibitors (CDK4/6i) significantly improve progression‐free survival and have become the standard therapy for estrogen receptor‐positive/human epidermal growth factor receptor 2‐negative metastatic breast cancer patients. Treatment surveillance by radiological imaging has some limitations in detection and repeated biopsy genomic profiling is not clinically feasible. Serial circulating tumor DNA (ctDNA) analysis may provide insights into treatment response. Here we performed serial ctDNA analysis (n = 178) on 33 patients. Serial ctDNA analysis identified disease progression with sensitivity of 75% and specificity of 92%. In eight of 12 patients (61%) responding to CDK4/6i who eventually developed progressive disease, serial sampling every 3 or 6 months captured the initial rise of ctDNA with an average lead time of 3 months. In three of eight patients that did not respond to CDK4/6i (progressive disease at first radiological assessment, 3 months), biweekly sequencing within the first cycle of CDK4/6i treatment (1 month) detected sustained ctDNA levels (≥0.2% variant allele frequency), with lead time of 2 months. Serial ctDNA analysis tracked RECIST response, including clinically challenging scenarios (bone metastases or small‐sized target lesions), as well as detecting acquired genetic alterations linked to CDK4/6i resistance in the G₁ to S transition phase. Circulating tumor DNA analysis was more sensitive than carcinoembryonic antigen or cancer antigen 15‐3 serum tumor markers at monitoring tumor response to CDK4/6i treatment. Our findings indicated the possible clinical utility of serial ctDNA analysis for earlier progressive disease detection and real‐time monitoring of CDK4/6i response.

Abstract P1-15-02: Low incidence of hepatitis B reactivation after chemotherapy in Japanese breast cancer patients with resolved HBV

Background: Recently, chemotherapy-induced reactivation of hepatitis B virus (HBV) has been reported not only in patients with HBV surface antigen positive (HBsAg+) but also in patients with resolved HBV (HBsAg-, anti-HBV-core antibody positive (anti-HBc+). The incidnce of HBV reactivation after adjuvant/neo-adjuvant chemotherapy for breast cancer in patients with resolved HBV infection remains unclear. In this study, we surveyed the incidence of HBV reactivation in Japanese breast cancer patients who received adjuvant/neo-adjuvant chemotherapy. Methods: A total of 3042 breast cancer patients who received neoadjuvant and/or adjuvant chemotherapy from June 2008 to December 2016 were included in this study. HBsAg, anti-HBc and anti-HBV-surface antibody (anti-HBs) were tested before chemotherapy. Serum HBV-DNA levels were subsequently measured and monitored for one year after the completion of adjuvant/neo-adjuvant chemotherapy if the patient exhibited a resolved HBV infection. Results: Of the 3042 patients (pts), 32 (1.05%)cases were positive for HBsAg and 2992 pts were negative for HBsAg. 301 pts (9.9 %) were revealed resolved HBV infection; 221 pts were with anti-HBc+ and anti-HBs+, 40 pts were with anti-HBc+ and anti-HBs-, and 130 pts were with anti-HBc- and anti-HBs+. Of the 130 pts with anti-HBc- and anti-HBs+, 77 pts were previously vaccinated for hepatitis B. The antibody-positive rate by age group was 2.7% (1/37) for patients in their 20s, 4.1% (14/344) for those in their 30s, 6.5% (67/1037) for those in their 40s, 9.4% (77/817) for those in their 50s, 16.6% (109/655) for those in their 60s, 20% (30/150) for those in their 70s, and 0% (0/2) for those in their 80s. Among the 301 pts with resolved HBV infection, 71 pts were monitored for one year after the completion of their chemotherapy. The median monitoring period was 579 days (386-3458). In our monitoring period, only one patient (1.4%) was diagnosed with HBV reactivation based on a slightly elevated HBV-DNA level at 1-year-test. No death or hepatitis due to HBV reactivation occurred during the monitoring period. Conclusions: The prevalence of resolved HBV infection in Japan showed an increasing trend with age. Adjuvant/neoadjuvant chemotherapy for breast cancer patients with resolved HBV infection has a risk of HBV reactivation. Our study suggested the risk of reactivation was low and the risk of a flare of HBV disease could be controlled with screening and carefully monitoring.

Citation Format: Takayo Fukuda, Masaya Hattori, Yukinori Ozaki, Lina Inagaki, Mari Hosonaga, Ippei Fukada, Kokoro Kobayashi, Fumikata Hara, Takayuki Kobayashi, Sachiyo Yoshio, Takayuki Ueno, Toshimi Takano, Shinji Ohno. Low incidence of hepatitis B reactivation after chemotherapy in Japanese breast cancer patients with resolved HBV [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-15-02.

Trastuzumab and fulvestrant combination therapy for women with advanced breast cancer positive for hormone receptor and human epidermal growth factor receptor 2: a retrospective single-center study

BACKGROUND

Trastuzumab and fulvestrant combination therapy is one of the treatment options for patients with hormone receptor- and human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer; however, there are limited studies evaluating the efficacy of this combination therapy.

METHODS

We retrospectively reviewed the data of women with hormone receptor- and HER2-positive metastatic breast cancer who received trastuzumab and fulvestrant combination therapy between August 1997 and August 2020 at the Cancer Institute Hospital. The primary endpoint of this study was progression-free survival, and the secondary endpoints were response rate, overall survival and safety.

RESULTS

We reviewed the data of 1612 patients with recurrent or metastatic breast cancer, of which 118 patients were diagnosed with hormone receptor- and HER2-positive breast cancer. Of these, 28 patients who received trastuzumab and fulvestrant combination therapy were eligible for this study. The median treatment line for advanced breast cancer was 6 (range, 1-14), the median progression-free survival was 6.4 months (95% confidence interval [CI], 3.46-8.17), and the median overall survival was 35.3 months (95% CI, 20.0-46.7). Of the 28 patients, partial response was observed in 1 (4%), stable disease in 17 (61%), and progressive disease in 10 (36%) patients. The disease control rate was 64%. Adverse events of grade ≥ 3 were not observed.

CONCLUSIONS

Trastuzumab and fulvestrant combination therapy showed moderate clinical efficacy and no severe toxicity after standard anti-HER2 treatment, which is a reasonable treatment option for patients with hormone receptor- and HER2-positive metastatic breast cancer. These data contribute to understanding the efficacy of trastuzumab and fulvestrant combination therapy as control data for further development of anti-HER2 agents plus hormone therapy.

A phase II study of sequential treatment with anthracycline and taxane followed by eribulin in patients with HER2-negative, locally advanced breast cancer (JBCRG-17)

Purpose

The sequence of taxanes (T) followed by anthracyclines (A) as neoadjuvant chemotherapy has been the standard of care for almost 20 years for locally advanced breast cancer (LABC). Sequential administration of eribulin (E) following A/T could provide a greater response rate for women with LABC.

Methods

In this single-arm, multicenter, Phase II prospective study, the patients received 4 cycles of the FEC regimen and 4 cycles of taxane. After the A/T-regimen, 4 cycles of E were administered followed by surgical resection. The primary endpoint was the clinical response rate. Eligible patients were women aged 20 years or older, with histologically confirmed invasive breast cancer, clinical Stage IIIA (T2–3 and N2 only), Stage IIIB, and Stage IIIC, HER2-negative.

Results

A preplanned interim analysis aimed to validate the trial assumptions was conducted after treatment of 20 patients and demonstrated that clinical progressive disease rates in the E phase were significantly higher (30%) than assumed. Therefore, the Independent Data Monitoring Committee recommended stopping the study. Finally, 53 patients were enrolled, and 26 patients received the A/T/E-regimen. The overall observed clinical response rate (RR) was 73% (19/26); RRs were 77% (20/26) in the AT phase and 23% (6/26) in the E phase. Thirty percent (8/26) of patients had PD in the E phase, 6 of whom had achieved cCR/PR in the AT phase. Reported grade ≥ 3 AEs related to E were neutropenia (42%), white blood cell count decrease (27%), febrile neutropenia (7.6%), weight gain (3.8%), and weight loss (3.8%).

Conclusion

Sequential administration of eribulin after the A/T-regimen provided no additional effect for LABC patients. Future research should continue to focus on identifying specific molecular biomarkers that can improve response rates.

Abstract P4-08-29: Lymphatic invasion is an independent risk factor in patients with small node-negative luminal breast cancer

[Background]

In patients with node-negative (N0), hormone receptor-positive, human epidermal growth factor receptor (HER2) -negative (luminal) breast cancer, the impact of lymphatic invasion (ly) on the prognosis remains to be clarified.

[Methods]

Among 3,158 patients with primary breast cancers who underwent surgery in our institute from January 2007 to December 2009, we analyzed 1027 N0 luminal invasive breast cancers without preoperative systemic therapy. The luminal breast cancer was defined as hormone receptor-positive (ER of ≥ 10% or PgR of ≥ 10%) and HER2-negative (immunohistochemistry: 0, 1+ or FISH: ratio &lt; 2.0) cancer in the postoperative pathological specimen. ly was defined as positive when cancer cell nests were detected within the lymph duct in the whole specimen. N0 was confirmed pathologically by the sentinel lymph node biopsy in all the patients. The Fisher's exact test was used for comparison between different categories. The distant recurrence rate (DRR) was analyzed using the Kaplan-Meier method and the log-rank test. For multivariate analysis, Cox's regression analysis was performed.

[Results]

The median follow-up period was 103.8 months (range: 5.6-128.8). Recurrence with distant metastasis occurred in 26 patients (2.5%). There were 5 (0.7%) deaths related to breast cancer. ly was detected in 240 patients (23.4%). In the ly-positive group, the tumor size was larger (p = 0.007), and the nuclear grade (NG) was higher (p &lt; 0.001) than in the ly-negative group. Postoperative endocrine therapy (p &lt; 0.001) and postoperative chemotherapy (p &lt; 0.001) were more frequently employed for patients with ly-positive tumor. The univariate analysis showed that ly positivity (p &lt; 0.001), large tumor size (p &lt; 0.001), high NG (p &lt; 0.001), PgR negativity (p = 0.002) and the history of adjuvant chemotherapy (p &lt; 0.001) were associated with high DRR. In the multivariate analysis, large tumor size (p = 0.007) and PgR negativity (p = 0.015) remained significant. Although positive ly had a risk ratio of 2.2, it was not an independent risk factor.When restricted to T1 tumor (n = 899), the aforementioned factors still showed prognostic value in the univariate analysis, among which ly positivity (p = 0.004)remained significant together with PgR negativity (p = 0.047)in themultivariate analysis.The 8-year DRR was very favorable (0.8%) in patients with ly-negative T1N0 tumor while it was modest (6.6%) in patients with ly-positive T1N0 tumor (p &lt; 0.001). Only 1.3% of the patients had received adjuvant chemotherapy in the ly-negative group while 27% of the patients had in the ly-positive group.

[Conclusion]

Lymphatic invasion was associated with higher DRR although it was not independent in the multivariate analysis among patients with N0 luminal breast cancer. When restricted to patients with T1N0 luminal breast cancer, the presence of ly was independently associated with higher risk of distant recurrence. It suggests that the assessment of ly is clinically more relevant when considering treatment options for small luminal breast cancer.

Citation Format: Abe T, Ito Y, Fukada I, Shibayama T, Ono M, Kobayashi T, Kobayashi K, Takahashi S, Horii R, Akiyama F, Iwase T, Ueno T, Ohno S. Lymphatic invasion is an independent risk factor in patients with small node-negative luminal breast cancer [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 P4-08-29.

Predictive impact of absolute lymphocyte counts for progression-free survival in human epidermal growth factor receptor 2-positive advanced breast cancer treated with pertuzumab and trastuzumab plus eribulin or nab-paclitaxel

Background

Although peripheral blood-based parameters (PBBPs) are reported as prognostic indicators in patients with breast cancers, their utility has not been studied in human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC). Tumor-infiltrating lymphocytes (TILs) might be a predictive factor in patients with HER2-positive ABC treated with pertuzumab and trastuzumab (PT) plus docetaxel. We aimed to evaluate whether PBBPs could have predictive value in HER2-positive ABC treated with pertuzumab and trastuzumab (PT) combined with eribulin (ERI) or nab-paclitaxel (Nab-PTX).

Methods

Data from 51 patients included in two single-arm, phase II trials were included in this retrospective-prospective study; the ERI + PT (N = 30) and Nab-PTX + PT (N = 21) combinations were registered under clinical trials number UMIN000012375 and UMIN000006838, respectively. We assessed PBBPs using prospectively collected data and investigated the association with progression-free survival (PFS); we evaluated absolute lymphocyte count (ALC), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). The cutoff values for ALC, NLR, and PLR were set at 1000 or 1500 cells/μL, 2, and 250, respectively.

Results

PFS was significantly improved in patients with ALC ≥1500/μL compared to those with ALC 1000–, <1500/μL or ALC < 1000/μL (P = 0.0106). High baseline ALC was significantly associated with improved PFS (≥1500/μL; hazard ratio [HR]: 0.3715; 95% confidence interval [CI]: 0.1735–0.7955; P = 0.0108). In contrast, improved PFS was not significantly associated with NLR or PLR. Improved PFS in patients with ALC ≥1500/μL was observed irrespective of visceral metastasis or chemotherapy regimen.

Conclusions

Our results showed that baseline ALC was a predictive factor for PFS in HER2-positive ABC treated with PT irrespective of combined chemotherapy regimen. Anti-tumor effects might be mediated not only by the tumor microenvironment, but also by systemic peripheral circulating lymphocytes. Baseline systemic parameters such as peripheral lymphocyte count might be beneficial in addition to disease extent for predicting the efficacy of PT treatment.

Trial registration

UMIN000012375, registration date: 21NOV2013, and UMIN000006838, registration date: 6DEC2011.

Abstract P2-09-31: Predictive impact of absolute lymphocyte counts for progression-free survival in HER2-positive advanced breast cancer treated with pertuzumab and trastuzumab plus eribulin or nab-paclitaxel

Background: Tumor-infiltrating lymphocytes might be a one of predictive outcome of human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC) patients (pts) who treated with trastuzumab and pertuzumab (TP) plus docetaxel. Although peripheral blood-based parameter (PBBP) is reported as a prognostic indicator of patients with early breast cancers, utility of PBBP has not been studied in HER2-positive ABC.

Objective:The aim of our study was to determine whether PBBP is significant for predictive efficacy in HER2-positive ABC treated with TP combined with eribulin (ERI) or nab-paclitaxel (Nab-PTX).

Methods: The 51 patients' data from two single arm phase II trials was included in this retrospective-prospective study; ERI + TP (n=30) or Nab-PTX + TP (n=21) registered with UMIN000012375 or UMIN000006838, respectively. We assessed the PBBP in prospectively collected data and investigated their association with progression-free survival (PFS). In consideration of PBBP, we evaluated absolute lymphocyte count (ALC), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). The cutoff values of ALC, NLR, and PLR were set at 1000 cells/μL, 2, and 250, respectively.

Results:Median age at baseline was 58 years (range: 31-77). Median number of previous chemotherapy was 3 (range: 1-10). Pts had multiple metastases, 53% with LNs, 35% with bone, 25% with lung, 20% with liver, and 6% with brain. The objective response rate (CR+PR) and clinical benefit rate (CR+PR+ more than 6 month SD) were 37% (n=19) and 59% (n=30), respectively. The median PFS of all pts was 301 days (range: 21-1281). The PFS of pts with ALC-High was significantly better than those of ALC-low (hazard ratio (HR): 2.74, 95% confidence interval (CI): 1.28 to 5.86; p= .0097). Furthermore, improved PFS was obtained in pts with ALC greater than 1500 cells/μL compared with less than 1000 cells/uL (HR: 4.05, 95% CI: 1.60 to 11.6; p= .0029). Significant associations seem to exist irrespective of number of previous chemotherapy. Since we combined different studies for evaluating PBBP, ERI and Nab-PTX were calculated separately. Marginally significant associations between ALC and PFS were obtained both in ERI (HR: 2.18, 95% CI: 0.87 to 5.60; p=.0973) and Nab-PTX (HR: 3.26, 95% CI: 0.80 to 12.4; p=.0939). The PFS of NLR-low pts was significantly better than those of NLR-high (HR: 2.29, 95% CI: 1.01 to 5.90; p= .0477), but this statistical difference was inferior to those of ALC. There was no significant association between PLR and PFS.

Conclusions: Pre-treatment ALC-High was significantly correlated with favorable PFS of pts treated with TP irrespective of combination chemotherapy in HER2-positve ABC. Prolonged PFS of TP combination therapy might be obtained mediating through host systemic onco-immunity. These data obtained here suggest that a usefulness of ALC for selecting pts who might have clinical benefit from TP combination therapy for heavily treated HER2-positve ABC.

Citation Format: Araki K, Ito Y, Fukada I, Kobayashi K, Ohno S, Miyagawa Y, Imamura M, Kira A, Takatsuka Y, Egawa C, Suwa H, Miyoshi Y. Predictive impact of absolute lymphocyte counts for progression-free survival in HER2-positive advanced breast cancer treated with pertuzumab and trastuzumab plus eribulin or nab-paclitaxel [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 P2-09-31.

Cystoid Macular Edema during Treatment with Paclitaxel and Bevacizumab in a Patient with Metastatic Breast Cancer: A Case Report and Literature Review

We present a case of a metastatic breast cancer patient with cystoid macular edema (CME) occurring during treatment with paclitaxel and bevacizumab. She had a history of neoadjuvant chemotherapy and partial mastectomy plus axillary lymph node dissection for stage IIB left-breast cancer. Twenty-four months later, she was diagnosed with multiple bone metastases and underwent chemotherapy with paclitaxel and bevacizumab. Thirty-three months after the initiation of the chemotherapy, she noticed bilateral blurred vision. The retinal thickening with macular edema was observed by optical coherence tomography, resulting in a diagnosis of CME. With cessation of paclitaxel and administrating ocular instillation of a nonsteroidal anti-inflammatory drug, her macular edema gradually reduced and disappeared in a month. While CME caused by chemotherapy is very rare, taxane may cause ocular adverse events such as CME. It is important to urge patients to consult an ophthalmologist promptly when they have visual complaints during taxane chemotherapy.

A Case of Recurrent Breast Cancer Identified by Pulmonary Tumor Thrombotic Microangiopathy

Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare, cancer-related, pulmonary complication that causes hypoxia and pulmonary hypertension. We report on a 42-year-old woman who was diagnosed with recurrent breast cancer that was detected due to the presence of PTTM. Eleven months after surgery for heterochronous bilateral cancer of the left breast, she developed progressive dyspnea but computerized tomography showed no pulmonary thromboembolism, and a transthoracic echocardiography revealed mild pulmonary hypertension. She was diagnosed with PTTM by cytology from pulmonary artery catheterization and perfusion lung scintigraphy. Also, the patients complained of back pain after admission, bone scintigraphy showed multiple bone metastases. Despite the early diagnosis of PTTM, her platelet count decreased, her performance status rapidly deteriorated, and her dyspnea worsened. Thus, we could not treat her with chemotherapy. She died due to respiratory failure 19 days after admission. To the best of our knowledge, this is the first report of recurrent breast cancer identified by the manifestation of PTTM. Although PTTM is a rare phenomenon, it should be considered in the differential diagnosis of acute dyspnea or pulmonary hypertension in patients with breast cancer. Furthermore, upon diagnosis, the patient should be referred to a cardiologist as soon as possible.

Abstract P5-15-11: Eribulin should be a candidate strategy in combination with pertuzumab plus trastuzumab for taxane pretreated HER2 positive advance breast cancer

Background: Pertuzumab (P) improves clinical outcome when combined with docetaxel and trastuzumab (T). The efficacy of continuing multiple anti-HER2 therapy including P and/or T after initial progression is unclear. Eribulin mesylate (ERI) is able to overcome taxane (TAX) resistance advanced breast cancer (ABC). The objective of this study is to investigate the efficacy and safety of ERI plus P and T for both TAX and T pretreated HER2-positive ABC. Methods: This is a single institute, open-label, single-arm, Phase II study with pharmacokinetics (PK) of ERI (UMIN000012375). The initial dose of P is 840 mg, followed by 420 mg q3w; the initial dose of T 8 mg/kg, followed by 6 mg/kg q3w; ERI is administered at 1.4 mg on Days 1 and 8 of each cycle, q3w. Dose reductions of ERI (to 1.1 and 0.7 mg/m2) were permitted to manage any toxicity (more than grade 3). Patients (Pts) must have previous treatment with both TAX and T. The primary endpoint is assessed overall response rate (ORR). Secondary endpoints include progression-free survival (PFS), overall survival (OS), safety, and PK of ERI. Left ventricular ejection function (LVEF) was evaluated before and end of this study. Results: Thirty Pts were enrolled. Median age at baseline was 57 years. Half of Pts had endocrine positive. All Pts were treated with TAX and T. Twenty-one Pts were treated with anthracycline-based treatment (70%). Median number of previous chemotherapy was 4 (2-5). Pts had multiple metastases, 40% with bone, 36.7% with lung, 20% with liver, and 10% with brain. Pts received a median number of 8 cycles of ERI (mean dose 1.2 ± 0.19 mg/sqm), 8 cycles of both P and T. Total number of 27 Pts needed to reduce dose of ERI because of adverse events (AEs) especially grade 3 neutropenia. The ORR (CR+PR) was 34.8% (95% CI 16.4-57.3, n=23) with median PFS of 42.6 weeks (95% CI 20.3-51.9, n=30). Clinical benefit rate (CR+PR+≥6 month SD) was 60.9% (95% CI 16.4-57.3%). T-DM1 pretreated affected poor outcome than the other factors (p=0.0011). The most common grade 3/4 AEs were neutropenia in 20 Pts (66.7%) without febrile neutropenia. Grade 1/2 AEs were fatigue in 24 Pts (80%), anorexia in 23 Pts (76.7%), anemia in 22 Pts (73.3%), diarrhea in 20 Pts (66.7%), peripheral neuropathy in 16 Pts (53.3%), and hand-foot syndrome in 12 Pts (43.3%). Baseline LVEF was 67%. One Pt had asymptomatic LVEF decrease (below an absolute value of 55%). Otherwise, there was no overall decrease in mean LVEF from baseline. Nine points (pre-dose, end of infusion, 0.5, 1, 2, 4, 24, 72, and 168 h after ERI) of PK analyses were evaluated in 6 Pts, and 3 point (pre-dose, end of infusion, and 168 h after ERI) in 10 Pts. PK parameters of ERI were as follows; Maximum plasma concentration (Cmax) was 375.96 (257.6-531.8) ng/ml, terminal half-life was 36.807 (31.90-40.80) h, total clearance was 1.945 (1.15-3.15) L/h/m2. Cmax of ERI was not correlated with neutrophil count (R2=0.2338, n=16). Conclusions: The combination of ERI plus P and T was well tolerated; no new safety signals ware observed. PK parameter of ERI were as same as previous reports when combined with both P and T. ERI might be a one of strategy in combination with P plus T for TAX pretreated HER2 positive ABC.

Citation Format: Araki K, Fukada I, Kobayashi K, Takahashi S, Ito Y. Eribulin should be a candidate strategy in combination with pertuzumab plus trastuzumab for taxane pretreated HER2 positive advance breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-15-11.

Imatinib could be a new strategy for pulmonary hypertension caused by pulmonary tumor thrombotic microangiopathy in metastatic breast cancer

Introduction

Pulmonary tumor thrombotic microangiopathy (PTTM) is rare, cancer-related pulmonary complication leading to hypoxia, pulmonary hypertension, and heart failure. The standard treatment for PTTM is not established. However, imatinib, a tyrosine kinase inhibitor of the PDGF receptor, may cause regression of pulmonary hypertension and pulmonary artery remodeling in PTTM.

Case descriptions

We report two cases of PTTM who received an anti-PDGF agent of imatinib for PTTM developed during chemotherapy for metastatic breast cancer. Case 1: 61-year-old woman who underwent resection of the left breast and axillary lymph node dissection and received adjuvant chemotherapy (CAF followed by docetaxel), then endocrine therapy for 5 years. Twelve years after surgery, multiple bone and mediastinal lymph node metastases occurred. She was under treatment with eribulin for one year but admitted because of rapid progressing dyspnea. Case 2: 45-year-old woman with metastatic breast cancer in multiple bones was under treatment for 5 years. Receiving capecitabine, she suffered from dyspnea for 2 months, she was admitted to our hospital with diagnosis of severe hypoxia. In both cases, the wedged pulmonary arterial blood cell sampling revealed cytologically malignant cells which confirmed the diagnosis of PTTM. They were treated with imatinib, which alleviated pulmonary hypertension. However, they died due to progression of metastatic breast cancer.

Discussion and Evaluation

Single use of imatinib did not showed sufficient efficacy. It is necessary to conduct a well-designed clinical trial using chemotherapies combined with imatinib for PTTM.

Conclusions

Imatinib, which alleviated pulmonary hypertension, could be a new strategy for pulmonary tumor thrombotic microangiopathy in patient with metastatic breast cancer.

Eribulin-induced liver dysfunction as a prognostic indicator of survival of metastatic breast cancer patients: a retrospective study

Background

Eribulin is a non-taxane, microtubule dynamics inhibitor that increases survival of patients with metastatic breast cancer. Although eribulin is well tolerated in patients with heavily pretreated disease, eribulin-induced liver dysfunction (EILD) can occur, resulting in treatment modification and subsequent poor disease control. We aimed to clarify the effect of EILD on patient survival.

Methods

The medical records of 157 metastatic breast cancer patients treated with eribulin between July 2011 and November 2013 at Cancer Institute Hospital were retrospectively analyzed. EILD was defined as 1) an increase in alanine aminotransferase or aspartate aminotransferase levels >3 times the upper limit of normal, and/or 2) initiation of a liver-supporting oral drug therapy such as ursodeoxycholic acid or glycyron. Fatty liver was defined as a decrease in the liver-to-spleen attenuation ratio to <0.9 on a computed tomography scan.

Results

EILD occurred in 42 patients, including one patient for whom eribulin treatment was discontinued due to severe EILD. The patients who developed EILD had significantly higher body mass indices (BMIs) than those who did not develop EILD (24.5 vs. 21.5, respectively; P < 0.0001), with no difference in the dose intensity of eribulin between the two groups (P = 0.76). Interestingly, the patients with EILD exhibited significantly longer progression-free survival (PFS) and overall survival (OS) than those without EILD (P = 0.010 and P = 0.032, respectively). Similarly, among 80 patients without liver metastasis, 19 with EILD exhibited significantly longer PFS and OS than the others (P = 0.0012 and P = 0.044, respectively), and EILD was an independent prognostic factor of PFS (P = 0.0079) in multivariate analysis. During eribulin treatment, 18 patients developed fatty liver, 11 of whom developed EILD, with a median BMI of 26.7.

Conclusions

Although EILD and fatty liver occurred at a relatively high frequency in our study, most of the patients did not experience severe adverse effects. Surprisingly, the development of EILD was positively associated with patient survival, especially in patients without liver metastases. EILD may be a clinically useful predictive biomarker of survival, but further studies are needed to confirm these findings in another cohort of patients.

Therapeutic effect of taxanes on metastatic breast cancer of various immunohistochemical subtypes

Taxane drugs play a central role in chemotherapy for breast cancer. However, previous studies have reported that taxanes are relatively ineffective in patients with operable luminal breast cancer compared with other subtypes. Between January 2000 and August 2008, 293 patients with metastatic breast cancer were treated with taxanes in The Cancer Institute Hospital of The Japanese Foundation for Cancer Research and were included in the present study. The patients were divided into 4 subtypes based on the immunohistochemically evaluated estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor 2 (HER2) status. The clinicopathological features, response rate (RR) and time to progression (TTP) were analyzed retrospectively. In total, 159 patient tissues were classified as luminal type (ER⁺ and/or PgR⁺ and HER2^-), 28 patient tissues were classified as luminal-HER2 type (ER⁺ and/or PgR⁺ and HER2⁺), 57 patient tissues were classified as HER2 type (ER^-, PgR^- and HER2⁺), and 49 patient tissues were classified as triple-negative type (ER^-, PgR^- and HER2^-). Among the 4 subtypes, the clinical benefit rate was 51.6, 78.6, 71.9 and 40.8%, respectively. There were significant differences in TTP between subtypes (median TTP, 8.3 months in luminal, 14.1 months in luminal-HER2, 10.6 months in HER2, and 4.2 months in triple-negative; P<0.001). Patients with luminal type tumors had a significantly longer TTP than patients with triple-negative type tumors. The present data suggested that the immunohistochemical subtypes were associated with the therapeutic effect of taxanes for metastatic breast cancer and that taxanes yielded an acceptable RR and TTP in luminal metastatic breast cancer. Additional investigations are required to elucidate the predictive markers of taxane therapy for patients with metastatic breast cancer in each immunohistochemical subtype.

Abstract P4-02-13: The pattern of tumor shrinkage is associated with prognosis in low grade luminal early breast cancer during neoadjuvant chemotherapy

BACKGROUND: In neoadjuvant chemotherapy (NAC) for early breast cancer, the pathological response rate in estrogen receptor (ER)-positive tumors has been low in comparison with those of ER-negative tumors. Therefore, surrogate makers other than the pCR rate are needed during NAC for luminal breast cancer. Using MRI, we analyzed the patterns of tumor shrinkage after NAC as a surrogate prognostic factor in low grade luminal breast cancer. METHODS: Of 854 patients who had received NAC in a single institute from Jan. 2000 to Dec. 2009, 183 patients with low grade luminal breast cancer were retrospectively evaluated for this study. They were defined as ER and/or PgR positive in more than 10% of cancer cells and HER2 negative (IHC 0, 1+ or FISH &lt;2.0) with nuclear grade 1 and 2. RESULTS: The median observation period was 67.9 months following surgery, and recurrence was observed in 31 patients (16.9%). The median age was 49 (22-76) years. One hundred eighty patients received anthracycline-containing chemotherapy, and 158 received taxane. There were 16 deaths (8.7%) related to breast cancer. We categorized the patterns of tumor shrinkage by MRI into 6 types: concentric shrinkage (CS), diffuse decrease (DD), reduction to small foci (RSF), decrease of intensity only (DIO), no change (NC), and enlargement (EL). According to our categorization, CS occurred in 97 (53.0%), RSF in 7 (3.8%), DD in 62 (33.9%), DIO in 7 (3.8%), NC in 5 (2.7%), and EL in 5 (2.7%). As expected, there were statistically significant differences in both the median DFS and OS in each pattern of tumor shrinkage (p &lt;0.001 and p=0.001, respectively); in particular, the CS pattern had excellent prognosis. Multivariate analysis demonstrated that concentric shrinkage was the only significant good prognostic factor for OS (p=0.015). CONCLUSIONS: Tumor shrinkage patterns as revealed by MRI could be important surrogate prognostic factors for NAC in early low grade luminal breast cancer.

Citation Format: Fukada I, Araki K, Kobayashi K, Gomi N, Horii R, Akiyama F, Takahashi S, Iiwase T, Ohno S, Ito Y. The pattern of tumor shrinkage is associated with prognosis in low grade luminal early breast cancer during neoadjuvant chemotherapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-02-13.

Abstract P3-14-10: Phase Ia/Ib study of taselisib (GDC-0032), a potent and selective phosphoinositide 3-kinase inhibitor, in Japanese patients with advanced solid tumors or hormone receptor-positive locally advanced or metastatic breast cancer (JO29196 study)

Background:

Taselisib (GDC-0032) is an orally bioavailable, potent and selective phosphoinositide 3-kinase (PI3K) inhibitor. Preclinical data showed that taselisib had increased antitumor activity against PIK3CA (gene encoding the PI3Kα isoform) mutant tumors. This study aimed to investigate the safety, tolerability and pharmacokinetics (PK) of taselisib as monotherapy and in combination with fulvestrant in Japanese patients (pts).

Materials and methods:

A 3+3 design was used. In Phase Ia, pts with advanced solid tumors received taselisib tablet monotherapy (2, 4 or 6 mg once daily [QD]), and safety and PK were evaluated. In Phase Ib, pts with hormone receptor-positive locally advanced or metastatic breast cancer received taselisib (2 or 4 mg QD) in combination with fulvestrant (500 mg at a time), and safety and PK were evaluated. Maximal administered doses of 6 mg QD as a single agent and 4 mg QD in combination with fulvestrant were based upon prior clinical trial experience with taselisib (Juric D. et al. AACR 2013, Abstract LB-64; Juric D. et al. SABCS 2013, Abstract PD1-3).

Results:

As of 15 Mar 2015, 9 pts (PIK3CA mutant: 2 pts) were enrolled in Phase Ia and 3 pts in Phase Ib. Phase Ia dose-escalation study has been completed and Phase Ib is ongoing.

In Phase Ia, no dose-limiting toxicity (DLT) was observed at any dose level tested (maximum administered dose of 6 mg QD). Common (≥3 pts) adverse reactions (ARs) were stomatitis (4 pts), rash (3 pts) and diarrhea (3 pts); the only Grade ≥3 AR was neutropenia (1 pt). Partial response was observed in 1 pt who received taselisib 4 mg and had a PIK3CA mutant breast tumor. Stable disease was observed in 4 pts. Cmax and AUC indicated a dose-proportional PK profile of taselisib within the dose range tested. Moreover, taselisib PK in Japanese pts was consistent with the PK reported from North American and European pts (Juric D. et al. AACR 2013, Abstract LB-64).

In Phase Ib, 3 pts received taselisib 2 mg in combination with fulvestrant and no DLT was observed. Preliminary ARs were similar to those with monotherapy and no Grade ≥3 AR was reported. Confirmation of tolerability of taselisib 4 mg in combination with fulvestrant is under evaluation.

Conclusion:

Taselisib monotherapy was well tolerated in Japanese pts up to a dose of 6 mg, which is the recommended dose in non-Japanese pts. Promising preliminary activity of monotherapy was observed in advanced solid tumors, especially in a pt with PIK3CA mutant tumor. The combination of taselisib 2 mg with fulvestrant is well tolerated. Investigation of tolerability of taselisib 4 mg in combination with fulvestrant is ongoing. Final results of this study will be presented here at the Symposium this year.

Citation Format: Kobayashi T, Nakano K, Tomomatsu J, Nara E, Ito Y, Kobayashi K, Fukada I, Araki K, Shimomura A, Shimoi T, Kodaira M, Yunokawa M, Yonemori K, Shimizu C, Nakamura K, Kotani N, Inatani M, Tamura K, Takahashi S. Phase Ia/Ib study of taselisib (GDC-0032), a potent and selective phosphoinositide 3-kinase inhibitor, in Japanese patients with advanced solid tumors or hormone receptor-positive locally advanced or metastatic breast cancer (JO29196 study). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-14-10.

Impact of immunohistological subtypes on the long-term prognosis of patients with metastatic breast cancer

PURPOSE

Although improved long-term prognoses for patients with metastatic breast cancer (MBC) have been demonstrated, few reports address overall survival (OS) with sufficient follow-up. Furthermore, the relevance of immunohistological subtypes to OS in MBC has not been clarified.

METHODS

We evaluated, retrospectively, the OS of patients who had been initiated on systemic therapy for MBC between 2000 and 2008.

RESULTS

The subjects of this study were 527 patients with MBC treated by systemic therapy. The median survival time (MST) was 55.5 months. The MST for each immunohistological subtype was as follows: luminal, 59.9 months; luminal-HER2, not reached; triple-negative, 18.6 months; and HER2-enriched, 49.9 months. According to multivariate analysis, metastasis-free intervals of ≥2 years and treatment with anthracycline for MBC were predictive of better OS. The predictors of shorter OS included disease progression after first-line treatment for MBC, triple-negative, and all histological factors, except papillotubular carcinoma, with liver metastasis, and having three or more initial metastatic sites.

CONCLUSIONS

The prognosis of the patients with MBC in this series was better than that reported before 2000, which is probably attributable to the use of novel, improved pharmacological agents. For example, luminal-HER2 tumors can be treated using both aromatase inhibitors and trastuzumab. Because of the lower toxicities, it is now possible to administer these agents for longer periods, resulting in better prognoses.

Combination chemotherapy with mitomycin C and methotrexate is active against metastatic HER2-negative breast cancer even after treatment with anthracycline, taxane, capecitabine, and vinorelbine

Background

Combination chemotherapy with mitomycin C and methotrexate (MM) was reported to be effective for 24% of patients with metastatic breast cancer (MBC) who had been treated with anthracycline and taxane. Antimetabolites such as capecitabine and antitubulins such as vinorelbine have been generally used for MBC treatment after anthracycline and taxane. A subsequent choice of chemotherapy should be offered to patients with MBC who have kept good performance status (PS) after being aggressively treated with anthracycline, taxane, capecitabine, and vinorelbine (ATCV), but is not well clear which treatment is superior to others after ATCV. In this study, we examined whether MM treatment is a good choice following ATCV.

Methods

We retrospectively reviewed the medical records of 31 patients with HER2-negative metastatic breast cancer who were treated with MM following ATCV. One cycle of MM was defined as MMC 8 mg/m² on day 1 and MTX 60 mg/m² on day 1 and day 15, administered intravenously every 4 weeks.

Results

Response rate and clinical benefit rate were 9.7 and 19.4%, respectively. Median times to progression and times to failure were 3.9 and 3.7 months, respectively. Adverse events of grade 3 and/or 4 were observed in 36% patients. Thrombocytopenia of grade 3 or 4 was 12.9 and 3.2%. Grades 3 and 4 of leucopenia and anemia were 12.9 and 9.7%, respectively.

Conclusion

MM is effective and tolerable for MBC patients even after aggressive treatment with ATCV. MM is one treatment choice when patients have kept good PS and bone marrow function even after multiple regimens of chemotherapy.

Decreased hormonal sensitivity after childbirth rather than the tumor size influences the prognosis of very young breast cancer patients

Purpose

There is a significant difference in the mean tumor size between very young breast cancer patients and their elder counterparts. A simple comparison may show obvious prognostic differences. We investigated the prognostic impact of age by reducing the influence of the tumor size, which is thought to be a confounding factor.

Patients and methods

We investigated 1,880 consecutive pT1-4N0-3M0 breast cancer patients treated at less than 45 years of age between 1986 and 2002 and conducted a case–control study of breast cancer subjects less than 30 years of age. Each patient (Younger than 30) was matched with a corresponding control subject (Elder counterpart) based on an age 15 years above the patient’s age, a similar tumor size and a status of being within 1 year after surgery. In addition, we assessed 47 patients with pregnancy-associated breast cancer (PABC). The levels of hormone receptors were measured using an enzyme immunoassay (EIA), and receptor-positive cases were divided into “weakly” and “strongly” positive groups based on the median value. Years from the last childbirth (YFLC) was categorized as “recent” and “past” at the time point of 8 years.

Results

There were fewer past YFLC cases, more partial mastectomy cases, a higher rate of scirrhous carcinoma or solid-tubular carcinoma in the Younger than 30 group than in the Elder counterpart group. The rates of a PgR-negative status in the Younger than 30 and Elder counterpart groups were 45.1 and 29.9%, respectively, As for the relationship between the PgR-negative rate and YFLC, the rates of a PgR-negative status in the past YFLC, nulliparous, recent YFLC and PABC groups were 31.9, 37.7, 44.4 and 65.7%, respectively. On the other hand, the rates of strongly positive cases were 42.6, 30.2, 22.2 and 8.6%, respectively. The 10-year recurrence-free survival rates in the Younger than 30, Elder counterpart and PABC groups were 61.7, 65.6 and 54.1%, respectively. The differences between the groups were not significant. In a multivariate analysis, independent prognostic facers included the number of lymph node metastases (4–9, HR:3.388, 95% CI 1.363–8.425, p = 0.0086, over 10, HR: 6.714, 2.033–22.177, p = 0.0018), solid-tubular carcinoma (HR 3.348, 1.352–8.292, p = 0.0090), scirrhous carcinoma (HR 2.294, 1.013–5.197, p = 0.0465) and past YFLC (HR 0.422, 0.186–0.956, p = 0.0387). An age younger than 30 was not found to be an independent prognostic factor.

Conclusions

The prognosis of the very young women was the same as their elder counterparts with a matched tumor size, and age was not identified to be an independent prognostic factor according to the multivariate analysis. Recent childbirth probably influences the prognosis of patients younger than 30 years of age with breast cancer by lowering hormonal sensitivity.

Abstract P5-13-12: Risk of hepatitis B virus (HBV) reactivation in hepatitis B surface antigen negative/ hepatitis B core antibody positive and/or hepatitis B surface antibody positive breast cancer patients who receive chemotherapy

Background: Recently, chemotherapy-induced reactivation of hepatitis B virus (HBV) has been reported not only in patients positive for hepatitis B surface antigen (HBsAg), but also in patients negative for it. Although HBV reactivation is associated with substantial morbidity and mortality in patients undergoing cancer chemotherapy, the exact frequency and risk for HBV reactivation in HBsAg-negative breast cancer patients who receive chemotherapy remains unclear. In this study, we examined the frequency and risk for HBV reactivation in Japanese breast cancer patients who have received chemotherapy.

Methods: A total of 562 HBsAg-negative breast cancer patients received chemotherapy from June 2008 to May 2009 at the Cancer Institute Hospital of JFCR in Japan. Antibody to hepatitis B core antigen (anti-HBc) and antibody to hepatitis B surface antigen (anti-HBs) were screened for before chemotherapy in all patients. In patients who were positive for anti-HBc and/or anti-HBs, serum HBV-DNA levels were measured and monitored during and after chemotherapy.

Results: 93 (17.4%) HBsAg-negative breast cancer patients were found to have resolved hepatitis B (HBsAg-negative, anti-HBc-positive and/or anti-HBs-positive). One patient was found to be positive for HBV DNA before the initiation of chemotherapy and received adjuvant chemotherapy with Entecavir prophylaxis. 65 patients received chemotherapy in adjuvant or neoadjuvant setting, 28 patients received it for metastatic disease. In our monitoring period (median 15.3 months), no HBsAg-negative/ anti-HBc-positive and/or anti-HBs-positive breast cancer patients developed HBV reactivation during and after their chemotherapy.

Conclusions: A number of HBsAg-negative breast cancer patients have received chemotherapy with a risk for HBV reactivation; however, it has been determined that conventional chemotherapy regimens for breast cancer are unlikely to increase the risk of developing HBV reactivation in these patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-13-12.

Abstract P6-06-45: Predictive significance of the mucocutaneous toxicities, but not dose intensity of capecitabine for the treatment of lapatinib plus capecitabine in patients with HER2 positive metastatic breast cancer

Background: There are no definitive predictive markers, except HER2 overexpression, for anti-HER2 therapeutic sensitivity of patients (Pts) with HER2-positive breast cancer. The aim of this study was to evaluate clinical predictive factors for lapatinib plus capecitabine (LAPCAP) in Pts with HER2 positive metastatic breast cancer (HER2MBC).

Methods: This retrospective observational study was used data from our single institutional medical record system from June 2009 to March 2013. Evaluation of female Pts with HER2MBC who were treated with LAPCAP (LAP at 1250 mg/day continuously plus CAP at 2000 mg/m2 on days 1 through 14 of a 21-day cycle) included baseline clinical characteristics, dose modifications of LAPCAP, clinical efficacy, and incidence of adverse events (AEs). Dose-intensity was compared with reference standard regimens. The Kaplan Meier method was used to estimate time to progression free survival (PFS).

Results: A total 76 Pts were included in this analysis. At a median follow-up of 20 months, median age was 56 years (range, 36 to 75) and 41 of 76 Pts had received prior (neo- or) adjuvant chemotherapy including 18 trastuzumab (Tmab) containing regimen. Visceral metastases (Mets) were identified in 49, bone Mets in 37, lymph nodes Mets in 36, brain Mets in 17, and chest wall Mets in 16. The median number of prior chemotherapy or hormonal therapy for MBC before LAPCAP was 2 (range, 0 to 13), and 66 of 76 Pts had previously received Tmab containing regimen with taxanes for 40 Pts, vinorelbine for 36, CAP for 29, and hormonal therapies for 15. In LAPCAP, the overall response rate was 21% including 2 CRs and 14 PRs, and the clinical-benefit rates which had more than 6-month SD was 60%. During initial 12 months observation, 93% of Pts had any AEs. The most common AEs were hand-foot syndrome (HFS) in 55 Pts. Those Pts who had HFS had better PFS than those who did not have (p = 0. 23×10−4). Since HFS was one of the well-known AEs associated with CAP, we sought whether CAP dose influenced PFS or not. However, we did not find any relationship between cumulative or relative dose intensity of CAP and PFS in Pts who treated with LAPCAP. Because several studies with EGFR-targeted agents showed a positive correlation between cutaneous toxicities and outcomes, we sought whether the incidence of any AEs other than HFS influenced PFS in 76 Pts. HFS, and diarrhea, as well as skin rash were statistically significant favorable factors (p = 0. 23×10−4, 0. 60×10−2, and 0. 28×10−1) in Log rank analysis. Furthermore, median PFS of Pts who had all 3 AEs (n = 21) were 377 days, while 84 days (n = 7) who had not (p = 0.58×10−8). We did not find any other clinical predictive factors except these 3 AEs. Furthermore, we compared 20 Pts with longer PFS who had more than 12-month to 26 Pts with shorter PFS that had less than 6-month. Longer PFS had more statistically significant incidence of diarrhea (p = 0. 49×10−2), HFS (p = 0. 49×10−2), and skin rash (p = 0.36×10−1) than shorter one.

Conclusions: In LAPCAP, dose of CAP did not influence PFS, but EGFR inhibitor related toxicities might be alternative predicative markers for LAPCAP in HER2MBC.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-45.

Magnetic resonance imaging with concentric shrinkage as a prognostic factor in patients with luminal breast cancer during neoadjuvant chemotherapy

e11587

Background: The important characteristics of breast cancer is its tumor heterogeneity and response to neoadjuvant chemotherapy (NAC). We analyzed the patterns of tumor shrinkage as a prognostic indicator after NAC for luminal breast cancer. Methods and Results. Methods: Of 854 patients who had received NAC in the single institute between January 2000 and December 2009, 265 luminal breast cancerwere retrospevively examined. Luminal breast cancer was defined as ER and/or PgR positive in more than 10% of cancer cells and HER2 negative (IHC 0, 1+ or FISH <2.0). Before and after NAC, the primary lesion was evaluated by enhanced MRI in 235 patients. Results: The median follow-up period was 51.4 months. 38 patients(16.2%) experienced recurrence after a median DFI of 49.1 months. The median age was 50 and 232 patients received anthracycline containing chemotherapy and 179 patients received taxane. 120 out of 235 patients exhibited concentric shrinkage pattern. Multivariate analysis for DFS identified Age(49>), strong ER/PgR positivity and concentric shrinkage as significantly favorable, and lymph node metastases as significantly unfavorable prognostic factors. Multivariate analysis for OS identified tumor size as significantly unfavorable prognostic factors(p=0.012). Conclusions: the tumor shrinkage pattern could be an important prognostic factor for luminal breast cancer and this suggests that a concentric shrinkage pattern of response may be infrequently associated with chemotherapy-resistant residual cancer cells.

Clear cell sarcoma of the neck which metastasized to the mammary gland

Malignant neoplasms very rarely metastasize to the mammary gland, the incidence of which is reported as 0.5-2%. Clear cell sarcoma is a rare neoplasm, accounting for approximately 1% of all soft tissue tumors, which commonly occurs in the distal extremities of young adults aged approximately 20 to 40 years. So it is also called malignant melanoma of soft parts because it frequently produces melanin. We report a case of a 26-year-old woman who presented with a neck mass. The mass was surgically removed, and pathological diagnosis was clear cell sarcoma of the neck, harboring the EWS-ATF1 chimeric gene. Computed tomography detected a right breast mass 11 months after operation. She was referred to our department, and the right breast tumor was resected. Histopathological examination revealed a 2.5-cm, well-defined mass composed of nests of small, spindle-shaped tumor cells with abundant, clear cytoplasm containing round nuclei and prominent nucleoli. The tumor cells were immunohistochemically positive for HMB45, S-100, and Melan-A. These findings led to a diagnosis of metastasis of clear cell sarcoma to the mammary gland. This is the first report of clear cell sarcoma of the neck which metastasized to the mammary gland.

[A case of recurrent pancreatic cancer with lung metastasis responding to S-1 combined gemcitabine chemotherapy]

The patient was a 54-year-old male. In July 2004, he underwent resection of the pancreatic body tail region to treat pancreatic body tail cancer. On histopathological examination, the stump of the extirpated specimen was positive for tumor cells. After surgery, 10 courses of therapy with gemcitabine hydrochloride(GEM, 1, 000 mg/m(2), 3-week administration followed by 1-week discontinuation)were performed, and follow-up was continued. In February 2006, local relapse was detected. Chemotherapy with GEM was administered for 1 year and 9 months. However, in November 2007, an increase in the recurrent lesion size and right lung metastasis were noted. The regimen was switched to combination therapy with S-1 and GEM(S-1 60 mg/m(2) day, continuous administration on days 1 to 14 and 2-week discontinuation; and GEM 1, 000 mg/ m(2), administered on days 8 and 15). After the end of the 11th course, PET-CT revealed the disappearance of FDG accumulation in the recurrent and metastatic lesion sites. During the treatment period, there were no grade 3 or higher adverse reactions. The patient is being treated at the outpatient clinic (as of January 2009).