Investigating the immunological function of alpha-2-glycoprotein 1, zinc-binding in regulating tumor response in the breast cancer microenvironment.

BACKGROUND: Alpha-2-glycoprotein 1, zinc-binding (ZAG), a secreted protein encoded by the AZGP1 gene, is structurally similar to HLA class I. Despite its presumed immunological function, little is known about its role in tumor immunity. In this study, we thus aimed to determine the relationship between the expression of AZGP1/ZAG and the immunological profiles of breast cancer tissues at both the gene and protein level. METHODS: Using a publicly available gene expression dataset from a large-scale breast cancer cohort, we conducted gene set enrichment analysis (GSEA) to screen the biological processes associated with AZGP1. We analyzed the correlation between AZGP1 expression and immune cell composition in breast cancer tissues, estimated using CIBERSORTx. Previously, we evaluated the infiltration of 11 types of immune cells for 45 breast cancer tissues using flow cytometry (FCM). ZAG expression was evaluated by immunohistochemistry on these specimens and analyzed for its relationship with immune cell infiltration. The action of ZAG in M1/M2 polarization models using primary cultures of human peripheral blood mononuclear cells (PBMC)-derived macrophage (Mφ) was analyzed based on the expression of M1/M2 markers (CD86, CD80/CD163, MRC1) and HLA class I/II by FCM. RESULTS: AZGP1 expression was negatively correlated with multiple immunological processes and specific immune cell infiltration including Mφ M1 using GSEA and CIBERSORTx. ZAG expression was associated with decreased infiltration of monocytes/macrophages, non-classical monocytes, and myeloid-derived suppressor cells in tumor tissues assessed using FCM. In in vitro analyses, ZAG decreased the expression of CD80, CD163, MRC1, and HLA classes I/II in the M1 polarization model and the expression of CD163 and MRC1 in the M2 polarization model. CONCLUSION: ZAG is suggested to be a novel immunoregulatory factor affecting the Mφ phenotype in breast cancer tissues.

Changes in cell-free DNA after short-term palbociclib and fulvestrant treatment for advanced or metastatic hormone receptor-positive and human epidermal growth factor 2-negative breast cancer.

PURPOSE: Here, we investigated the potential predictive and elucidating efficacy of cell-free DNA (cfDNA) changes on clinical outcomes and biological effects, respectively, after short-term palbociclib and fulvestrant treatment for patients with hormone receptor (HR)-positive and human epidermal growth factor 2 (HER2)-negative advanced or metastatic breast cancer (ABC). METHODS: In this secondary analysis of the Japan Breast Cancer Research Group-M07 (FUTURE) trial, blood cfDNA was obtained before palbociclib treatment and on day 15 of cycle one (28-day cycle). Target enrichment was performed using next-generation sequencing; progression-free survival (PFS) was compared based on cfDNA changes between baseline and day 15 of cycle one after combination therapy. RESULTS: Fifty-six patients (112 paired blood samples) were examined. The median follow-up time was 8.9 months. PIK3CA (30.4%, 17/56), FOXA1 (30.4%, 17/56), and ESR1 (28.6%, 16/56) were most frequently mutated at baseline. The number of mutated genes was significantly decreased on day 15 compared with that at baseline (paired t test: P value = 0.025). No significant difference was observed in PFS (decrease group, 7.9 m vs the others, 9.3 m; log-rank P value = 0.75; hazard ratio, 1.13; 95% confidence interval, 0.53-2.41). Among patients without previous aromatase inhibitor treatment (n = 15), three (20%) had ESR1 mutations after progression to fulvestrant. CONCLUSION: No significant association was observed between changes in mutated genes after short-term palbociclib and fulvestrant treatment and disease progression; a significant reduction in cfDNA mutation level was observed on day 15 of cycle one. Clinical meanings of cfDNA should be investigated in the future trials.

Prognostic value of the 21-Gene Breast Recurrence Score® assay for hormone receptor-positive/human epidermal growth factor 2-negative advanced breast cancer: subanalysis from Japan Breast Cancer Research Group-M07 (FUTURE trial).

PURPOSE: This study aimed to determine whether the 21-Gene Breast Recurrence Score® assay from primary breast tissue predicts the prognosis of patients with hormone receptor-positive and human epidermal growth factor 2-negative advanced breast cancers (ABCs) treated with fulvestrant monotherapy (Group A) and the addition of palbociclib combined with fulvestrant (Group B), which included those who had progression in Group A from the Japan Breast Cancer Research Group-M07 (FUTURE trial). METHODS: Progression-free survival (PFS) and overall survival (OS) were compared using the log-rank test and Cox regression analysis based on original recurrence score (RS) categories (Low: 0-17, Intermediate: 18-30, High: 31-100) by treatment groups (A and B) and types of ABCs (recurrence and de novo stage IV). RESULTS: In total, 102 patients [Low: n = 44 (43.1%), Intermediate: n = 38 (37.5%), High: n = 20 (19.6%)] in Group A, and 45 in Group B, who had progression in Group A were analyzed. The median follow-up time was 23.8 months for Group A and 8.9 months for Group B. Multivariate analysis in Group A showed that low-risk [hazard ratio (HR) 0.15, 95% confidence interval (CI) 0.04-0.53, P = 0.003] and intermediate-risk (HR 0.22, 95% CI 0.06-0.78) with de novo stage IV breast cancer were significantly associated with better prognosis compared to high-risk. However, no significant difference was observed among patients with recurrence. No prognostic significance was observed in Group B. CONCLUSION: We found a distinct prognostic value of the 21-Gene Breast Recurrence Score® assay by the types of ABCs and a poor prognostic value of the high RS for patients with de novo stage IV BC treated with fulvestrant monotherapy. Further validations of these findings are required.

Expression of hormone receptors is associated with specific immunological profiles of the breast cancer microenvironment.

BACKGROUND: Elucidating the unique immunoregulatory mechanisms in breast cancer microenvironment may help develop new therapeutic strategies. Some studies have suggested that hormone receptors also have immune regulatory functions, but their mechanisms are not fully understood. In this study, we have comprehensively analyzed the relationship between the expressions of estrogen (ER), progesterone (PgR), and androgen receptors (AR), and the immunological profile in breast cancer. METHODS: Using publicly available gene expression profile datasets, METABRIC and SCAN-B, the associations between the expressions of hormone receptors and the immune cell compositions in breast cancer tissue, estimated by CIBERSORTx algorithm, were analyzed. We histologically evaluated tumor-infiltrating lymphocytes (hTIL), PD-L1 (hPD-L1) expression, and the infiltration of 11 types of immune cells by flow cytometry (FCM) for 45 breast cancer tissue samples. The relationships between them and the expressions of ER, PgR, and AR of tumor tissues, evaluated immunohistochemically, were analyzed. RESULTS: Expressions of ESR1, PGR, and AR were negatively correlated with overall immune composition. Expressions of ER and AR, but not that of PgR, were inversely associated with hTIL and hPD-L1 expression. FCM analysis showed that the expressions of ER and AR, but not that of PgR, were associated with decreased total leukocyte infiltration. Both CIBERSORTx and FCM analysis showed that ER expression was associated with reduced infiltration of macrophages and CD4+ T cells and that of AR with reduced macrophage infiltration. CONCLUSION: Hormone receptor expression correlates with specific immunological profiles in the breast cancer microenvironment both at the gene and protein expression levels.

Difference of compliance rates for the recommendations in Japanese Guideline on Febrile Neutropenia according to respondents' attributes: the second report on a questionnaire survey among hematology-oncology physicians and surgeons.

PURPOSE: The Japanese Society of Medical Oncology (JSMO) published a guideline (GL) on febrile neutropenia (FN) in 2017. This study aims to identify promoting factors and disincentives for complying with GL recommendations according to attributes of doctors providing chemotherapy. METHODS: A questionnaire survey was conducted with SurveyMonkey™ for physician members of the Japanese Association of Supportive Care in Cancer and relevant academic organizations. Each question had four options (always do, do in more than half of patients, do in less than half, do not at all) and a free description form. Responses were analyzed according to the respondents' attributes. RESULT: Seven hundred eighty-eight out of retrieved 801 responses were available for analysis. Multivariable analysis demonstrated that the percentage of GL users was higher among women and Japanese Society of Clinical Oncology members. The overall compliance rate was higher among women, JSMO members, and board-certified medical oncologists. Internists emphasized the significance of collecting blood cultures at FN onset, and surgeons stressed the importance of G-CSF prophylaxis. Hematologists were less likely to adhere to recommendations on risk assessment of FN by the Multinational Association of Supportive Care in Cancer score and administration of gammaglobulin products. However, those are acceptable due to the characteristics of their practice. Eight recommendations had no difference in compliance rates between users and non-users, some of whose statements were ambiguous and discretionary. CONCLUSION: Women were more likely to use and adhere to GL. The recommendations should be developed considering the characteristics of specialty and subspecialty and avoiding ambiguity and discretionary statements.

A questionnaire survey on evaluation for penetration and compliance of the Japanese Guideline on Febrile Neutropenia among hematology-oncology physicians and surgeons.

PURPOSE: The Japanese Society of Medical Oncology published a guideline (GL) on febrile neutropenia (FN) in 2017. The study's purpose is to reveal how widely GL penetrated among physicians and surgeons providing chemotherapy. METHODS: A questionnaire survey was conducted with SurveyMonkey™ for members of the Japanese Association of Supportive Care in Cancer and relevant academic organizations. Each question had four options (always do, do in more than half of patients, do in less than half, do not at all) and a free description form. Responses were analyzed with statistical text-analytics. RESULT: A total of 800 responses were retrieved. Major respondents were experts with more than 10-year experience, physicians 54%, and surgeons 46%. Eighty-seven percent of respondents knew and used GL. Forty-eight percent assessed FN with Multinational Association of Supportive Care in Cancer (MASCC) score "always" or "more than half." Eighty-one percent chose beta-lactam monotherapy as primary treatment in high-risk patients. Seventy-seven percent did oral antibacterial therapy in low-risk patients ambulatorily. Seventy-eight percent administered primary prophylactic G-CSF (ppG-CSF) in FN frequency ≥ 20% regimen. Fifty-nine percent did ppG-CSF for high-risk patients in FN frequency 10-20% regimen. Ninety-seven percent did not use ppG-CSF in FN frequency < 10% regimen. The medians of complete and complete plus partial compliance rates were 46.4% (range 7.0-92.8) and 77.8% (range 35.4-98.7). The complete compliance rates were less than 30% in seven recommendations, including the MASCC score assessment. CONCLUSION: GL is estimated to be widely utilized, but some recommendations were not followed, presumably due to a mismatch with actual clinical practices in Japan.

Breast cancer survival among Japanese individuals and US residents of Japanese and other origins: a comparative registry-based study.

BACKGROUND: Breast cancer survival outcomes vary across different ethnic groups. We clarified the differences in clinicopathological and survival characteristics of breast cancer among Japanese, US residents with Japanese origin (USJ), and US residents with other origins (USO). METHOD: Using Surveillance, Epidemiology, and End Results (SEER) 18 dataset and Japanese Breast Cancer Society (JBCS) registry, we included patients first diagnosed with breast cancer between 2004 and 2015. We categorized the patients into three groups based on the database and the recorded ethnicity: Japanese (all those from the JBCS registry), USJ (those from SEER with ethnicity: Japanese), and USO (those from SEER with ethnicity other than Japanese). Excluding patients diagnosed after 2012, stage 0, and 4 patients, we examined the overall survival (OS) and breast cancer-specific survival (BCSS) using the Kaplan-Meier method and Cox proportional hazards models, adjusting for age, sex, cancer stage, and hormone receptor (HR) status. RESULTS: We identified 7362 USJ, 701,751 USO, and 503,013 Japanese breast cancer patients. The proportion of HR-positive breast cancer was the highest among USJ (71%). OS was significantly longer among Japanese and USJ than USO (Hazard ratio 0.46; 95% Confidence Interval [CI] 0.45-0.47 for Japanese and 0.66 [95% CI 0.59-0.74] for USJ) after adjusting for baseline covariates. BCSS was also significantly higher in the two groups (HR 0.53 [95% CI 0.51-0.55] for Japanese and 0.53 [95% CI 0.52-0.74] for USJ). CONCLUSIONS: In stage I-III breast cancer, Japanese and US residents with Japanese origin experienced significantly longer survival than US residents with non-Japanese origins.

[Two Cases of Pneumocystis Pneumonia during Adjuvant Chemotherapy for Breast Cancer].

In recent years, human immunodeficiency virus(HIV)-negative Pneumocystis pneumonia(PCP)onset has been occasionally seen in breast cancer. In particular, dose-dense epirubicin and cyclophosphamide(EC: ddEC)therapy, in which EC is administered every 2 weeks, has been generally used in clinical practice for early stage breast cancers. PCP may develop before and during postoperative chemotherapy. We report the cases of 2 patients who developed PCP during postoperative adjuvant chemotherapy. Case 1: A 62-year-old woman, who underwent postoperative EC therapy, developed PCP during the 4th EC cycle. During EC therapy, steroids(prednisolone[PSL])were administered at an average dose of 11.4mg/day, and the number of lymphocytes at the initiation of the 4th EC cycle was 516/mL. Case 2: After receiving 4 cycles of postoperative ddEC, a 27-year-old woman developed PCP after 1 cycle of docetaxel(DTX)administration. During ddEC therapy, PSL was administered at a dose of 17.14mg/day, and the number of lymphocytes at DTX administration was 311/mL. The onset of PCP is presumed to be related to the steroid dose administered and the number of lymphocytes. Therefore, determining effective indicators in patients at a high risk of PCP onset is important.

Comparison of tumor-infiltrating lymphocytes between primary and metastatic tumors in breast cancer patients.

The presence of tumor-infiltrating lymphocytes (TILs) is associated with favorable long-term outcome in breast cancer. However, little is known about changes in TILs during metastatic progression. To confirm our hypothesis that malignant tumors escape from the host immune system during metastasis, we evaluated the percentage of TILs in paired samples of primary and metastatic breast tumors. We retrospectively identified 25 patients with human epidermal growth factor receptor-2 (HER2+ , n = 14) and triple negative (TN, n = 11) early breast cancer diagnosed between 1990 and 2009 at Tokai University Hospital (Isehara, Japan) and who subsequently experienced regional or distant recurrence confirmed by tumor biopsy/resection. Hematoxylin-eosin-stained slides of these paired samples were evaluated for stromal TILs. Immunohistochemical staining was carried out using primary antibodies against CD4, CD8, Foxp3, programmed cell death ligand 1 (PD-L1), PD-L2, and HLA class I for characterizing the TILs and breast tumors. The percentage of TILs in the primary tumors was significantly higher (average 34.6%) than that in metastatic tumors (average 15.7%) (paired t-test, P = 0.004) and that of CD8+ and CD4+ T cells significantly decreased from primary to metastatic tumors (paired t-test, P = 0.008 and P = 0.026, respectively). The PD-L1, PD-L2, and HLA class I antibody expression changed from positive to negative and vice versa from the primary to the metastatic tumors. Tumors at first metastatic recurrence in HER2+ and TN breast cancers have a lower percentage of TILs and CD8+ and CD4+ T cells compared to primary tumors, which indicates that immune escape plays a role in tumor progression.

Feasibility and pharmacokinetics of combined therapy with S-1 and trastuzumab in patients with human epidermal growth factor receptor 2-positive metastatic or recurrent breast cancer.

BACKGROUND: To clarify the tolerance and pharmacokinetics of combined therapy with S-1 and trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic or recurrent breast cancer. METHODS: From January 2008 through to September 2009, combined therapy with S-1 and trastuzumab was given to 7 patients with HER2-positive metastatic or recurrent breast cancer. The incidence of adverse events and the pharmacokinetics of tegafur, 5-fluorouracil, and gimeracil in plasma were studied. RESULTS: One patient had grade 3 leukopenia, and another had a grade 3 elevation of alanine aminotransferase. All other adverse events were grade 2 or lower. The combination of S-1 and trastuzumab did not cause any new adverse events. The incidence of adverse events was similar to those associated with S-1 alone. The median number of treatment cycles was 11. The pharmacokinetics of tegafur, 5-fluorouracil, and gimeracil after treatment with S-1 plus trastuzumab did not markedly differ from those after S-1 alone. CONCLUSIONS: Combined therapy with S-1 and trastuzumab did not cause any new adverse events, administration continuity was good, and the therapy was well tolerated.

Efficacy of Nursing Interventions Using Motivational Interviewing Aimed at Weight Loss in Overweight/Obese Breast Cancer Patients Undergoing Endocrine Therapy.

OBJECTIVE: Obesity adversely impacts breast cancer treatment and outcomes. This study assessed the efficacy of nurses' motivational interviews (MI) in promoting weight loss among breast cancer patients. METHODS: Motivational Interviewing was performed at 4, 8, and 12 weeks from baseline in 27 overweight/ obese breast cancer patients receiving adjuvant endocrine therapy. An average weight loss rate of 5% at week 12 was the threshold for determining whether MI intervention was clinically meaningful. Clinical and sociodemographic variables were gathered from medical records and self-administered questionnaires. Body weight, body mass index (BMI), physical activity time, sedentary time, self-efficacy for weight loss, and mood scores were evaluated at baseline, 4, 8, 12, and 24 weeks. RESULTS: Significant reductions in body weight were observed throughout compared with baseline; 51.9% of participants attained the 5% weight loss target, but the average weight loss rate was 3.9% at week 12. BMI notably decreased at 8, 12, and 24 weeks compared with baseline. Physical activity increased significantly at 12 weeks, while sedentary time decreased at 8 and 24 weeks. CONCLUSIONS: Nursing-administered MI did not achieve the goal of 5% weight loss at week 12. However, it increased physical activity and reduced sedentary time, showing potential for promoting healthier habits.

Utility of Echo-planar Imaging with Compressed Sensitivity Encoding (EPICS) in the Evaluation of Small Breast Cancers Using Diffusion-weighted Imaging with Background Suppression (DWIBS).

PURPOSE: High b-value acquisition and diffusion-weighted imaging with background suppression (DWIBS) are desirable in high-specificity breast cancer diagnosis on non-contrast-enhanced magnetic resonance imaging; however, this inherently results in a lower signal-to-noise ratio (SNR). Compressed sensitivity encoding (C-SENSE), which combines SENSE with compressed sensing, improves the SNR by reducing noise. Recent technological improvements allow us to incorporate this acceleration technique into echo-planar imaging, called echo-planar imaging with C-SENSE (EPICS). This study aimed to compare image quality and reliability of the apparent diffusion coefficient (ADC) between DWIBS obtained using SENSE and EPICS in patients with small breast cancers. METHODS: Thirty-seven patients with pathologically confirmed breast cancer underwent DWIBS, and images were reconstructed using both conventional SENSE (SENSE-DWIBS) and EPICS (EPICS-DWIBS). Two board-certified radiologists independently evaluated lesion conspicuity (LC) and noise using a 5-point grading scale. The same 2 radiologists independently measured SNR, contrast-to-noise ratio (CNR), and the mean cancer ADC. The Pearson coefficient and Bland-Altman plot were applied to assess the accuracy of ADCs. RESULTS: LC scores were higher with EPICS than with SENSE, reaching significance for one reviewer but not the other reviewer. Noise ratings on visual evaluation were significantly lower with EPICS than with SENSE (P < 0.001 for both reviewers). SNR was significantly higher with EPICS than with SENSE (P < 0.005 for both reviewers). CNR was significantly higher with EPICS than with SENSE (P < 0.001 for both reviewers). Bland-Altman plots of cancer ADCs using EPICS-DWIBS and SENSE-DWIBS showed excellent concordance, with a bias of 0.026 × 10-3 mm2/s and limits of agreement ranging 0.054 × 10-3 mm2/s; the Pearson's correlation coefficient was 0.997 (P < 0.0001). CONCLUSION: EPICS enhances breast DWIBS image quality, with improved SNR and CNR and reduced noise levels. The ADCs of breast cancers obtained using EPICS were almost perfectly correlated with those obtained using conventional SENSE.

Real-world progression-free survival and overall survival of palbociclib plus endocrine therapy (ET) in Japanese patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer in the first-line or second-line setting: an observational study.

BACKGROUND: A recent large real-world study conducted in the United States reported the effectiveness of palbociclib plus aromatase inhibitor in HR+/HER2- advanced breast cancer (ABC). However, local clinical practice and available medical treatment can vary between Japan and Western countries. Thus, it is important to investigate Japanese real-world data. This observational, multicenter study (NCT05399329) reports the interim analysis of effectiveness of palbociclib plus ET as first-line or second-line treatment for HR+/HER2- ABC by estimating real-world progression-free survival (rwPFS) and overall survival (OS) in Japanese routine clinical practice. METHODS: Real-world clinical outcomes and treatment patterns of palbociclib plus ET were captured using a medical record review of patients diagnosed with HR+/HER2- ABC who had received palbociclib plus ET in the first-line or second-line treatment across 20 sites in Japan. The primary endpoint was rwPFS; secondary endpoints were OS, real-world overall response rate, real-world clinical benefit rate, and chemotherapy-free survival. RESULTS: Of the 677 eligible patients, 420 and 257 patients, respectively, had received palbociclib with ET as first-line and second-line treatments. Median rwPFS (95% confidence interval) was 24.5 months (19.9-29.4) for first-line and 14.5 months (10.2-19.0) for second-line treatment groups. Median OS was not reached in the first-line group and was 46.7 months (38.8-not estimated) for the second-line group. The 36-month OS rates for de novo metastasis, treatment-free interval (TFI) ≥ 12 months, and TFI < 12 months were 80.2% (69.1-87.7), 82.0% (70.7-89.3), and 66.0% (57.9-72.9), respectively. CONCLUSION: The addition of palbociclib to ET was effective for treating HR+/HER2- ABC in Japanese routine clinical practice.

Computed diffusion-weighted imaging with a low-apparent diffusion coefficient-pixel cut-off technique for breast cancer detection.

OBJECTIVE: This study aimed to compare the image quality and diagnostic performance of computed diffusion-weighted imaging (DWI) with low-apparent diffusion coefficient (ADC)-pixel cut-off technique (cDWI cut-off) and actual measured DWI (mDWI). METHODS: Eighty-seven consecutive patients with malignant breast lesions and 72 with negative breast lesions who underwent breast MRI were retrospectively evaluated. Computed DWI with high b-values of 800, 1200, and 1500 s/mm2 and ADC cut-off thresholds of none, 0, 0.3, and 0.6 (×10-3 mm2/s) were generated from DWI with two b-values (0 and 800 s/mm2). To identify the optimal conditions, two radiologists evaluated the fat suppression and lesion reduction failure using a cut-off technique. The contrast between breast cancer and glandular tissue was evaluated using region of interest analysis. Three other board-certified radiologists independently assessed the optimised cDWI cut-off and mDWI data sets. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis. RESULTS: When an ADC cut-off threshold of 0.3 or 0.6 (× 10-3 mm2/s) was applied, fat suppression improved significantly (p < .05). The contrast of the cDWI cut-off with a b-value of 1200 or 1500 s/mm2 was better than the mDWI (p < .01). The ROC area under the curve for breast cancer detection was 0.837 for the mDWI and 0.909 for the cDWI cut-off (p < .01). CONCLUSION: The cDWI cut-off provided better diagnostic performance than mDWI for breast cancer detection. ADVANCES IN KNOWLEDGE: Using the low-ADC-pixel cut-off technique, computed DWI can improve diagnostic performance by increasing contrast and eliminating un-suppressed fat signals.

Ataxia Telangiectasia in a Patient with Breast Cancer: A Case Report.

Ataxia telangiectasia (AT) is a rare autosomal recessive disorder caused by the pathological variants of the ATM gene. Owing to i ts r arity a nd n ature, complications of AT, such a s malignant tumors, a re often difficult to manage with standard imaging studies and treatments, and there are no established management strategies. We report the case of a woman who had AT in childhood and developed breast cancer in her 20s; the disease was successfully managed by the decision-making of multidisciplinary physicians professionals with ethics support. She was immunocompromised, ataxic, and mentally impaired. The patient's mother noticed a tumor in her right breast and subsequently brought her to our department. Although preoperative testing and surgical procedures were limited as AT is extremely radiosensitive, the patient was diagnosed with cT2N0M0 breast cancer and underwent right mastectomy and axillary lymph node sampling. The final diagnosis was pT2N0M0 pStage IIA mucinous carcinoma, and immunohistochemistry of the tumor specimen was estrogen receptor-positive, progesterone receptor-positive, and HER2-negative. Tamoxifen was administered as postoperative adjuvant therapy, and the patient has survived to date without recurrence. Here, we report our experience with breast cancer treatment for AT, along with a review of the literature.

Immunohistochemical Ki67 labeling index has similar proliferation predictive power to various gene signatures in breast cancer.

The objective of this study was to examine the association between the immunohistochemical Ki67 labeling index (IHC Ki67), Ki67 mRNA expression level, and first-generation gene signatures in a cohort of breast cancer patients. We assessed associations between IHC Ki67 and first-generation gene signatures in a panel of 39 tumor samples, using an oligonucleotide microarray. Gene expression analyses included Ki67 alone (MKi67), 21-gene signature, mitosis kinome score signature, and genomic grade index. Correlation coefficients were calculated by Spearman's rank correlation test. In all cases, IHC Ki67, MKi67, and three genetic markers were highly correlated (ρ, 0.71-0.97). Estrogen receptor (ER)-positive cases showed strong correlations between IHC Ki67 and other signatures (ρ, 0.79-0.83). The ER-negative cases showed slightly lower correlations (ρ, 0.58-0.73). In ER-positive cases, the low IHC Ki67 group showed significantly longer relapse-free survival than the high IHC Ki67 group (P = 0.007). This difference was confirmed by multivariate analysis. Our data indicate that IHC Ki67 shows similar predictive power for proliferation in ER-positive cancers as genomic markers. Further study of IHC Ki67 is needed to define prognostic factors and predictive factors for chemotherapy using central laboratory assessment.

Immunological profiles of the breast cancer microenvironment represented by tumor-infiltrating lymphocytes and PD-L1 expression.

Tumor-infiltrating lymphocytes (TILs) and programmed cell death 1 ligand 1 (PD-L1) are established prognostic and predictive biomarkers for certain breast cancer subsets. However, their association with the immune response complexity is not fully understood. Therefore, we analyzed the association between the immune cell fractions in breast cancer tissues and histologically assessed TIL (hTIL) and PD-L1 (hPD-L1). Forty-five tumor and eighteen blood samples were collected from patients with breast cancer. Total leukocyte counts, frequency of 11 immune cell populations, and PD-L1 expression in each cell fraction were evaluated by flow cytometry. TILs and PD-L1 were assessed by hematoxylin and eosin staining and immunohistochemistry, respectively. A higher hTIL score showed association with increased leukocyte infiltration, higher CD4+ and CD8+ T cell proportions, and lower natural killer and natural killer T cell proportions. PD-L1 was highly expressed in nonclassical monocytes, monocyte/macrophages, myeloid-derived suppressor cells, myeloid dendritic cells, dendritic cells, and other lineages in tumors. hPD-L1 positivity reflected PD-L1 expression accurately in these fractions, as well as increased leukocyte infiltration in tumors. These results indicate that hTILs reflect differences in the immune responses in the tumor microenvironment, and certain immune cell fractions are favorably expressed in the PD-L1 pathway in breast cancer microenvironments.

Post-marketing safety evaluation of S-1 in patients with inoperable or recurrent breast cancer: especially in patients treated with S-1 + trastuzumab.

OBJECTIVE: The purpose of this study was to assess the safety of S-1 in Japanese in inoperable or recurrent breast cancer patients. METHODS: A prospective post-marketing surveillance was performed at 313 sites in Japan in patients with inoperable or recurrent breast cancer treated with S-1. We examined 1361 patients between January 2006 and December 2007 with regard to the incidence of adverse drug reactions graded by the Common Terminology Criteria for Adverse Events (CTCAE), version 3.0. RESULTS: At least one adverse drug reaction was encountered by 858 patients, with an overall incidence of 63.0% (858/1361). The incidence of Grade 3 or higher adverse drug reactions in a descending order was 14.7% (200/1361). In this study, the most common combination drug was trastuzumab. The overall incidence of adverse drug reactions was 63.5% (431/679 patients) in patients treated with S-1 alone, and 55.9% (66/118 patients) in patients treated with S-1 + trastuzumab. CONCLUSIONS: Monotherapy with S-1 or combination therapy with S-1 + trastuzumab was well tolerated for inoperable or recurrent breast cancer patients.