Label-free multiphoton excitation imaging as a promising diagnostic tool for breast cancer.

Histopathological diagnosis is the ultimate method of attaining the final diagnosis; however, the observation range is limited to the two-dimensional plane, and it requires thin slicing of the tissue, which limits diagnostic information. To seek solutions for these problems, we proposed a novel imaging-based histopathological examination. We used the multiphoton excitation microscopy (MPM) technique to establish a method for visualizing unfixed/unstained human breast tissues. Under near-infrared ray excitation, fresh human breast tissues emitted fluorescent signals with three major peaks, which enabled visualizing the breast tissue morphology without any fixation or dye staining. Our study using human breast tissue samples from 32 patients indicated that experienced pathologists can estimate normal or cancerous lesions using only these MPM images with a kappa coefficient of 1.0. Moreover, we developed an image classification algorithm with artificial intelligence that enabled us to automatically define cancer cells in small areas with a high sensitivity of ≥0.942. Taken together, label-free MPM imaging is a promising method for the real-time automatic diagnosis of breast cancer.

Nuclear grade and comedo necrosis of ductal carcinoma in situ as histopathological eligible criteria for the Japan Clinical Oncology Group 1505 trial: an interobserver agreement study.

OBJECTIVE: The Japan Clinical Oncology Group 1505 trial is a single-arm multicentre prospective study that examined the possibility of non-surgical follow-up with endocrine therapy for patients with low-grade ductal carcinoma in situ. In that study, the eligible criteria included histopathological findings comprising low to intermediate nuclear grade and absence of comedo necrosis, and cases were entered according to the local histopathological diagnosis. Nuclear grade is largely based on the Consensus Conference criteria (1997), whereas comedo necrosis is judged according to the Rosen's criteria (2017). The purpose of this study was to standardize and examine the interobserver agreement levels of these histopathological criteria amongst the participating pathologists. METHODS: We held slide conferences, where photomicrographs of haematoxylin-eosin-stained slides from 68 patients with ductal carcinoma in situ were presented using PowerPoint. The nuclear grade and comedo necrosis statuses individually judged by the pathologists were analysed using κ statistics. RESULTS: In the first and second sessions, where 22 cases each were presented, the interobserver agreement levels of nuclear grade whether low/intermediate grade or high grade were moderate amongst 29 and 24 participating pathologists, respectively (κ = 0.595 and 0.519, respectively). In the third session where 24 cases were presented, interobserver agreement levels of comedo necrosis or non-comedo necrosis were substantial amongst 25 participating pathologists (κ = 0.753). CONCLUSION: Although the concordance rates in nuclear grade or comedo necrosis were not high in a few of the cases, we believe that these results could provide a rationale for employing the present criteria of nuclear grade and comedo necrosis in the clinical study of ductal carcinoma in situ.

Clinicopathological features of breast cancer patients with internal mammary and/or supraclavicular lymph node recurrence without distant metastasis.

BACKGROUND: Internal mammary and/or supraclavicular (IM-SC) lymph node (LN) recurrence without distant metastasis (DM) in patients with breast cancer is rare, and there have been few reports on its clinical outcomes. METHODS: We enrolled 4237 patients with clinical stage I-IIIC breast cancer treated between January 2007 and December 2012. Clinicopathological features of patients with IM-SC LN recurrence and patients with DM were retrospectively reviewed. RESULTS: With a median follow-up time 78 (range, 13-125) months after the primary operation, 14 (0.3%) had IM-SC LN recurrence without DM and 274 (6.5%) had DM at the first recurrence among 4237 patients. No statistical differences were found in the baseline characteristics of the primary tumor between the two groups. The 5-year overall survival (OS) rate after recurrence in patients with IM-SC LN recurrence was 51% compared with 27% in patients with DM (P = 0.040). In patients with IM-SC LN recurrence, clinically positive axillary LN at diagnosis and pathologically positive axillary LN at primary surgery were poor prognostic factors for distant disease-free survival (DDFS) (P = 0.004 and 0.007, respectively). Clinical and pathological axillary nodal status at primary surgery was associated with OS (P = 0.011 and 0.001, respectively). CONCLUSIONS: Patients with IM-SC LN recurrence without DM who had no clinical and pathological axillary LNs involved at primary surgery had a favorable prognosis. A larger validation study is required.

Characteristics of adverse events of endocrine therapies among older patients with breast cancer.

PURPOSE: To clarify the profile of adverse events from endocrine therapies in older patients. METHODS: We surveyed 15 subjective symptoms including hot flashes, sweating, knuckle stiffness, knee/shoulder joint pain, limb numbness, lethargy, forgetfulness, depressive state, irritated state, genital bleeding, leukorrhea increase, vaginal dryness, bone fracture, and weight gain by a questionnaire among 2044 patients over 55 years old (total number of answered sheets, 8875) and compared the results according to age (56-69 years old vs. ≥ 70 years old) and type of therapy (aromatase inhibitors (AIs) vs. selective estrogen receptor modulators (SERMs)). Among patients 56-69 years old, 6093 and 314 responses were from patients treated with AIs (1477 patients) and SERMs (123 patients), respectively, and 2292 and 176 responses were from those ≥ 70 years old treated with AIs (581 patients) and SERMs (51 patients), respectively. RESULTS: In patients ≥ 70 years old, sweating, knuckle stiffness, knee/shoulder joint pain, limb numbness, and lethargy were significantly more frequent/severe with AIs than with SERMs. In those aged 56-69, knuckle stiffness and vaginal dryness were significantly more frequent with AIs than with SERMs, but the opposite occurred for hot flashes, leukorrhea increase, genital bleeding, and weight gain. CONCLUSIONS: Among patients ≥ 70 years old, many symptoms were significantly more frequent/severe with AIs than with SERMs, compared with those aged 56-69, which suggests a difference in the profile of adverse events according to the type of endocrine therapy and the patient's age. It is important to consider the benefits and risks of each treatment to optimize endocrine therapy for older patients.

Pattern of Tumor Shrinkage during Neoadjuvant Chemotherapy Is Associated with Prognosis in Low-Grade Luminal Early Breast Cancer.

Purpose To evaluate the association between tumor shrinkage patterns shown with magnetic resonance (MR) imaging during neoadjuvant chemotherapy (NAC) and prognosis in patients with low-grade luminal breast cancer. Materials and Methods This retrospective study was approved by the institutional review board and informed consent was obtained from all subjects. The low-grade luminal breast cancer was defined as hormone receptor-positive and human epidermal growth factor receptor 2-negative with nuclear grades 1 or 2. The patterns of tumor shrinkage as revealed at MR imaging were categorized into two types: concentric shrinkage (CS) and non-CS. Among 854 patients who had received NAC in a single institution from January 2000 to December 2009, 183 patients with low-grade luminal breast cancer were retrospectively evaluated for the development set. Another data set from 292 patients who had received NAC in the same institution between January 2010 and December 2012 was used for the validation set. Among these 292 patients, 121 patients with low-grade luminal breast cancer were retrospectively evaluated. Results In the development set, the median observation period was 67.9 months. Recurrence was observed in 31 patients, and 16 deaths were related to breast cancer. There were statistically significant differences in both the disease-free survival (DFS) and overall survival (OS) rates between patterns of tumor shrinkage (P < .001 and P < .001, respectively). Multivariate analysis demonstrated that the CS pattern had the only significant independent association with DFS (P = .001) and OS (P = .009) rate. In the validation set, the median follow-up period was 56.9 months. Recurrence was observed in 20 patients (16.5%) and eight (6.6%) deaths were related to breast cancer. DFS rate was significantly longer in patients with the CS pattern (72.8 months; 95% confidence interval [CI]: 69.9, 75.6 months) than in those with the non-CS pattern (56.0 months; 95% CI: 49.1, 62.9 months; P ≤ .001). The CS pattern was associated with an excellent prognosis (median OS, 80.6 months; 95% CI: 79.3, 81.8 months vs 65.0 months; 95% CI: 60.1, 69.8 months; P = .004). Multivariate analysis demonstrated that the CS pattern had the only significant independent association with DFS (P = .007) and OS (P = .037) rates. Conclusion The CS pattern as revealed at MR imaging during NAC had the only significant independent association with prognosis in patients with low-grade luminal breast cancer. © RSNA, 2017.

Differences in expression of the cancer stem cell marker aldehyde dehydrogenase 1 among estrogen receptor-positive/human epidermal growth factor receptor type 2-negative breast cancer cases with early, late, and no recurrence.

BACKGROUND: The significance of the expression of aldehyde dehydrogenase 1 (ALDH1), a cancer stem cell marker, for predicting the recurrence of estrogen receptor (ER)-positive/human epidermal growth factor receptor type 2 (HER2)-negative breast cancer is still poorly understood. The value of ALDH1 in predicting the time of recurrence remains unknown. METHODS: In total, 184 patients with early distant recurrence, 134 patients with late distant recurrence, and 321 control patients without recurrence for more than 10 years after starting initial treatment for ER-positive/HER2-negative breast cancer, registered in 9 institutions, were analyzed. We assessed relationships between ALDH1 and other clinicopathological features, and ALDH1 expression was compared among the three groups. The relationship between ALDH1 expression and overall survival after recurrence was also evaluated in each group. RESULTS: The rates of ALDH1 expression positivity (more than 1 %) in the early, late, and no recurrence groups were 18.4 %, 13.4 %, and 8.4 %, respectively. ALDH1 expression correlated significantly with lymph node metastases (p = 0.048) and the Ki-67 labeling index (p < 0.001) in the early recurrence group. Multivariate analysis revealed ALDH1 expression to be significantly higher in the early recurrence group than in the no recurrence group (adjusted OR 2.140, 95 % CI 1.144-4.003, p = 0.016). Moreover, there was a significant difference in ALDH1 expression between the early and no recurrence groups receiving adjuvant endocrine therapy and chemotherapy (adjusted OR 4.625, 95 % CI 1.881-12.474, p < 0.001). However, there was no difference in ALDH1 expression between the late and no recurrence groups in univariate analysis (OR 1.507, 95 % CI 0.738-2.998, p = 0.253). In multivariate analysis, ALDH1 was not a factor independently predicting overall survival after the detection of recurrence (adjusted OR 1.451, 95 % CI 0.985-2.085, p = 0.059). CONCLUSIONS: Among patients with ER-positive/HER2-negative breast cancer, ALDH1 expression was more common in those with early recurrence, and this expression was found to be associated with a more aggressive breast cancer phenotype than that in the patients without recurrence. Further study is needed to clarify the prognostic significance of the heterogeneity of cancer stem cells and to confirm their role in resistance to chemotherapy.

Prognostic significance of histological therapeutic effect in preoperative chemotherapy for breast cancer.

To establish a prognostic prediction system, we examined the relationships between prognosis and histological therapeutic effect or ypTNM classification in 258 breast cancer patients who received neoadjuvant chemotherapy. The case distribution according to therapeutic effect was nine patients (3.5%) with Grade 0, 169 (65.5%) with Grade 1, 58 (22.5%) with Grade 2, and 22 (8.5%) with Grade 3. The 5-year overall survival (OS) rate by therapeutic effect was 56% in Grade 0, 81% in Grade 1, 87% in Grade 2, and 96% in Grade 3. The higher the therapeutic effect the better the prognosis, with a significant difference among the groups (P = 0.008). The case distribution according to ypTNM classification was 20 patients (7.8%) with Stage 0, 83 (32.2%) with Stage I, 77 (29.8%) with Stage II, and 78 (30.2%) with Stage III. The 5-year OS rate by ypTNM classification was 95% in Stage 0, 94% in Stage I, 89% in Stage II, and 59% in Stage III. While prognosis was mostly comparable in Stages 0 and I, in the other stages it became significantly worse as residual cancer increased (P < 0.001). The prognosis of breast cancer patients with neoadjuvant chemotherapy can be predicted by histological therapeutic effect and staging classification of residual cancer.

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.

Differences in clinical importance of Bcl-2 in breast cancer according to hormone receptors status or adjuvant endocrine therapy.

BACKGROUND: Bcl-2 plays an anti-apoptotic role, resulting in poor clinical outcome or resistance to therapy in most tumor types expressing Bcl-2. In breast cancer, however, Bcl-2 expression has been reported to be a favorable prognostic factor. The positive correlation of Bcl-2 with estrogen receptor (ER)/progesterone receptor (PR) status, and endocrine therapy frequently given for hormone receptor-positive tumors, may obscure the independent pathobiological role of Bcl-2. We constructed a large systematic study to determine whether Bcl-2 has an independent role in breast cancer. METHODS: Bcl-2 expression was immunohistochemically evaluated and compared with other clinicopathological factors, including clinical outcome, in 1081 breast cancer cases with long follow-up, separately analyzing 634 cases without any adjuvant therapy and 447 cases with tamoxifen monotherapy. The χ (2)-test for independence using a contingency table, the Kaplan-Meier method with the log-rank test, and a Cox proportional hazards model were used for the comparison of clinicopathological factors, assessment of clinical outcome, and multivariate analyses, respectively. RESULTS: In both patient groups, Bcl-2 expression strongly correlated with positive ER/PR status, low grade, negative human epidermal growth factor receptor 2 (HER2) status, and small tumor size, as previously reported. Bcl-2 expression did not independently predict clinical outcome in patients with ER-positive and/or PR-positive tumors or in those who received tamoxifen treatment; however, it was an independent unfavorable prognostic factor in patients with ER-negative/PR-negative or triple-negative (ER-negative/PR-negative/HER2-negative) tumors who received no adjuvant therapy. The latter was even more evident in postmenopausal women: those with hormone receptor-negative or triple-negative tumors lacking Bcl-2 expression showed a favorable outcome. CONCLUSION: Bcl-2 expression is an independent poor prognostic factor in patients with hormone receptor-negative or triple-negative breast cancers, especially in the absence of adjuvant therapy, suggesting that the anti-apoptotic effect of Bcl-2 is clearly exhibited under such conditions. The prognostic value of Bcl-2 was more evident in postmenopausal women. The present findings also highlight Bcl-2 as a potential therapeutic target in breast cancers lacking conventional therapeutic targets such as triple-negative tumors. The favorable prognosis previously associated with Bcl-2-positive breast cancer probably reflects the indirect effect of frequently coexpressed hormone receptors and adjuvant endocrine therapy.

Four types of ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery: classification of IBTR based on precise pathological examination.

We classified ipsilateral breast tumor recurrences (IBTRs) based on strict pathological rules. Ninety-six women who were surgically treated for IBTR were included. IBTRs were classified according to their origins and were distinguished based on strict pathological rules: relationship between the IBTR and the primary lumpectomy scar, surgical margin status of the primary cancer, and the presence of in situ lesions of IBTR. The prognosis of these subgroups were compared to that of new primary tumors (NP) in the narrow sense (NPn) that occurred far from the scar. Distant-disease free survival of IBTR that occurred close to the scar with in situ lesions and a negative surgical margin of the primary cancer (NP occurred close to the scar, NPcs) was similar to that of NPn. In contrast, IBTR that occurred close to the scar without in situ lesions (true recurrence (TR) that arose from residual invasive carcinoma foci, TRinv) had significantly poorer prognosis than NPn. IBTR that occurred close to the scar with in situ lesions and a positive surgical margin of the primary cancer (TR arising from a residual in situ lesion, TRis) had more late recurrences than NPcs. Precise pathological examinations indicated four distinct IBTR subtypes with different characteristics.

Extensive analysis of signaling pathway molecules in breast cancer: association with clinicopathological characteristics.

BACKGROUND: The aim of this study was to extensively analyze the signaling pathway molecules in breast cancer and to explore candidate biomarkers for clinicopathological relevance. METHODS: We assessed the expression of key factors in cell signaling, namely p-AKT, cyclin D1, P27, p-p70S6 K, p-4EBP1, and p-MAPK/ERK, within 338 invasive breast cancer patients. These factors were immunohistochemically examined in tumor tissues and assessed by staining score. Staining scores were analyzed by a clustering method to devise a new classification based on pathway activity. We investigated the relationships among staining scores, the clustering classification, and patient characteristics. RESULTS: The proportion of patients displaying high expression levels were as follows: p-AKT, 75%; cyclin D1, 12%; P27, 53%; p-p70S6 K, 37%; p-4EBP1, 19%; and p-MAPK/ERK, 3%. Patients were classified into two groups on the basis of staining scores. Group 1 (39%) included more positive cases for p-4EBP1, p-MAPK/ERK, and p-p70S6 K and fewer positive cases for P27 and cyclin D1 than Group 2 (61%). The clustering classification was significantly related to subgrouping by hormone receptor and HER2 (P < 0.001), nuclear grade (P < 0.001) and histological subtype (P = 0.034). A strong positive correlation was identified between p-AKT and P27, cyclin D1 and P27, p-p70S6 K and p-4EBP1, p-p70S6 K and p-MAPK/ERK, and between p-4EBP1 and p-MAPK/ERK. Levels of p-p70S6 K were significantly related to recurrence in both univariate (RR = 0.75, P < 0.001) and multivariate (RR = 0.71, P = 0.049) analyses. CONCLUSIONS: The present study helps us to understand the characteristics of signaling pathway status in breast cancers. Moreover, p-p70S6 K expression may be of use in predicting clinical outcome.

Incidence and prediction of invasive disease and nodal metastasis in preoperatively diagnosed ductal carcinoma in situ.

For breast cancer patients with a preoperative diagnosis of ductal carcinoma in situ (DCIS), sentinel lymph node (SN) biopsy has been proposed as an axillary staging procedure in selected patients with a higher likelihood of having occult invasive lesions. With detailed histological examination of primary tumors and molecular whole-node analysis of SNs, we aimed to validate whether this selective application accurately identifies patients with SN metastasis. The subjects were 336 patients with a preoperative needle-biopsy diagnosis of DCIS who underwent SN biopsy using the one-step nucleic acid amplification assay in the period 2009-2011. The incidence and preoperative predictors of upstaging to invasive disease on final pathology and SN metastasis, and their correlation, were investigated. Of the 336 patients, 113 (33.6%) had invasive disease, and 6 (1.8%) and 17 (5.0%) had macro- and micrometastasis in axillary nodes respectively. Of the 113 patients with invasive disease, 4 (3.5%) and 9 (8.0%) had macro- and micrometastasis. Predictors of invasive disease included palpability, mammographic mass, and calcifications (spread >20 mm), and intraductal solid structure, but no predictor was found for SN metastasis. Therefore, even though occult invasive disease was found at final pathology, most of the patients had no metastasis or only micrometastasis in axillary nodes. Predictors of invasive disease and SN metastasis were not completely consistent, so the selective SN biopsy for patients with a higher risk of invasive disease may not accurately identify those with SN metastasis. More accurate application of SN biopsy is required for patients with a preoperative diagnosis of DCIS.

Lapatinib-associated mucocutaneous toxicities are clinical predictors of improved progression-free survival in patients with human epidermal growth factor receptor (HER2)-positive advanced breast cancer.

This study is aimed to identify clinical predictors, other than HER2 overexpression, for the response to lapatinib plus capecitabine (LAPCAP) in patients with HER2-positive advanced breast cancer (HER2ABC). Data from our medical records of 76 patients from June 2009 to March 2013 were analyzed. Evaluations of these patients with HER2ABC treated with LAPCAP included baseline characteristics, dose modifications, efficacy, and incidence of adverse events (AEs). With a median follow-up of 20 months, the median number of prior therapies for ABC before LAPCAP was 2 (range 0-13), and 66 patients had previously received trastuzumab. For LAPCAP, the overall response rate was 21 %, and the clinical benefit rate was 60 %. During the initial 12-month observation period, 93 % of patients had AEs. The most common AE was hand-foot syndrome (HFS) in 55 patients. Progression-free survival (PFS) was better in patients who had HFS than in those who did not (p = 0.0002). Since HFS is a well-known AE associated with CAP, whether CAP dose affected PFS or not was investigated, but no positive relationship was found. Since several studies with EGFR-targeted agents have suggested a positive correlation between cutaneous toxicities and outcomes, whether the incidence of any AEs affected PFS or not was explored among 76 patients. HFS, diarrhea, and rash were significant favorable factors (p = 0.0002, 0.0088, and 0.0011). The median PFS of patients who had all three AEs was 13.2 months, compared with 2.6 months for those who did not (p = 0.00000174). Mucocutaneous toxicities may be predictors of the response to LAP in patients with HER2ABC.

Trastuzumab deruxtecan for human epidermal growth factor receptor 2-low advanced or metastatic breast cancer: recommendations from the Japanese Breast Cancer Society Clinical Practice Guidelines.

The Japanese Breast Cancer Society Clinical Practice Guidelines are published as timely guidance on clinical issues in breast cancer treatment in Japan. In the recent edition of these guidelines, we addressed a new clinical question 34 (CQ 34, systemic treatment part) "Is trastuzumab deruxtecan recommended for patients with unresectable or metastatic HER2-low breast cancer?" and a new future research question 7 (FRQ 7, pathological diagnosis part) "How is HER2-low breast cancer diagnosed for the indication of trastuzumab deruxtecan?". These questions address use of trastuzumab deruxtecan in patients with unresectable or metastatic HER2-low breast cancer who have previously received chemotherapy for metastatic disease. The strengths of evidence and recommendation were determined through a quantitative and qualitative systematic review using multiple outcomes, including efficacy and safety. We conclude that trastuzumab deruxtecan is recommended for this patient population (strength of recommendation: 1; strength of evidence: moderate; CQ34) and that HER2-low expression for the indication of trastuzumab deruxtecan should be diagnosed using companion diagnostics based on appropriate criteria (FRQ7).

Detection of occult invasion in ductal carcinoma in situ of the breast with sentinel node metastasis.

By definition, ductal carcinoma in situ (DCIS) - pre-invasive breast cancer - does not metastasize to the lymph nodes. However, since the introduction of molecular whole-node analysis using the one-step nucleic acid amplification assay for sentinel node (SN) biopsies, the number of patients with DCIS and SN metastasis has increased. The pathogenesis and clinical management of DCIS with SN metastasis remain controversial. In this case-control study, in order to elucidate the pathogenesis of SN metastasis in DCIS, we compared occult invasions between the SN-positive and SN-negative DCIS and investigated predictive factors of occult invasion. The subjects were 24 patients selected from 285 patients with a routine postoperative diagnosis of DCIS who had undergone SN biopsy using the one-step nucleic acid amplification whole-node assay between 2009 and 2011. Of these 24 patients, 12 were SN-positive, and 12 were SN-negative. The 12 SN-negative patients make up the control group and were selected from the 273 SN-negative patients based on patient characteristics. All paraffin blocks of the primary tumor from each patient were step-sectioned with 500-µm intervals until the block was exhausted and histopathologically examined. We analyzed 1830 step-sectioned slides and found occult invasions were more frequent in the SN-positive group (7/12, 58.3%) than in the SN-negative group (3/12, 25.0%). All occult invasions were <5 mm. There was no correlation between occult invasion and SN tumor burden, non-SN metastasis, or patient characteristics. Our results suggest true metastasis from occult invasion may be a potent pathogenesis indicating nodal metastasis in postoperatively diagnosed DCIS. Patient follow-up is required to elucidate the prognostic impact of nodal metastasis and occult invasion.

Interobserver concordance of Ki67 labeling index in breast cancer: Japan Breast Cancer Research Group Ki67 ring study.

The standardized assessment of Ki67 labeling index (LI) is of clinical importance to identify patients with primary breast cancer who could benefit from chemotherapy. In this study, we evaluated the interobserver concordance of Ki67 LI assessment. Six surgical pathologists participated and all the slides were prepared from archival breast cancer tissues fixed in 10% buffered formalin for 24 h and stained with MIB-1. Three independent studies were conducted. In the first study, 30 stained slides were assessed using two different methods: the scoring system, with a positive rate scored from 1 (0-9%) to 10 (90-100%) by visual estimate; and the counting method, with approximately 1000 cells counted in hot spots. In the second study, 20 tumors with Ki67 LI 5-25% were assessed, and in the third study, 15 printed photographs of stained slides were assessed to avoid variations by selecting different fields. In study 1, the counting system (intraclass correlation coefficient [ICC], 0.66 [95% confidence interval 0.52-0.78]) demonstrated a better correlation than the scoring system (ICC, 0.57 [0.42-0.72]). In study 2, the assessment for Ki67 LI of 5-25% demonstrated a correlation (ICC, 0.68 [0.50-0.81]) similar to that of study 1 (unrestricted range of Ki67 LI). In study 3, the assessment of Ki67 LI by counting yielded a good concordance (ICC, 0.94 [0.88-0.97]). In conclusion, there was better concordance with the counting system, and concordance was high when the assessed field was predetermined, indicating that the selection of the evaluation area is critical for obtaining reproducible Ki67 LI in breast cancer.

Secretory carcinoma of the breast and its histopathological mimics: value of markers for differential diagnosis.

AIMS: Secretory carcinoma (SC) is a rare histological type of breast cancer, and ETV6-NTRK3 gene fusion is highly specific to it. The differential diagnoses of SC include acinic cell carcinoma (ACCA) and cystic hypersecretory carcinoma (CHC), as well as invasive ductal carcinoma (IDC). For patients with these rare but distinctive histological subtypes, SC and its histopathological mimics should be differentiated from each other. However, differential markers have not yet been assessed systematically, and we aimed to identify and evaluate novel and existing markers. METHODS AND RESULTS: We reviewed 19 cases diagnosed initially as SC using integrated diagnostic techniques, including morphology, immunohistochemistry and molecular pathology, and validated promising markers in 445 breast cancers. We reclassified 19 formerly diagnosed 'SCs' into nine SCs, three ACCAs, three CHCs, three IDCs and one microglandular adenosis. We confirmed that ETV6-NTRK3 gene rearrangement and amylase positivity are good diagnostic markers for SC and ACCA, respectively. Vacuolar staining for adipophilin, positivity for α-lactalbumin and negativity for ETV6 rearrangement are diagnostic markers for CHC. CONCLUSIONS: In this study, we propose a panel of four markers (ETV6 rearrangement, amylase, α-lactalbumin and adipophilin) for distinguishing SC, ACCA, CHC and IDC. This simple but robust panel will serve pathologists well as a practical guide for reaching an appropriate diagnosis.

Intratumoral heterogeneity, treatment response, and survival outcome of ER-positive HER2-positive breast cancer.

BACKGROUND: ER+HER2+ breast cancer requires most types of systemic therapies perioperatively. However, treatment resistance is often experienced. The current study investigated the predictive and prognostic value of intratumoral heterogeneity and conventional clinicopathological factors in patients with ER+HER2+ breast cancer. METHODS: This research included two patient cohorts with ER+HER2+ breast cancer. Cohort A included patients who underwent surgery without neoadjuvant chemotherapy (NAC). Cohort B comprised patients who received NAC followed by surgery. Intratumoral heterogeneity was assessed via ER and HER2 double staining, and the number of cells stained with different patterns of ER and HER2 was counted. RESULTS: In total, 11 of 92 tumors in cohort A and four of 45 tumors in cohort B consisted exclusively of double-positive (ER+ and HER2+) cells (homogeneous). The rest had different combinations of cells (heterogeneous). The pathological complete response (pCR) rates differed based on tumoral cell components but not intratumoral heterogeneity. The pCR rate of tumors with ER-HER2+ cells but without HER2- cells was higher than that of others (45.5% vs 4.3%; p = 0.0013). Low ER and PgR Allred scores indicated better pCR rates than high scores (p = 0.0005 and 0.024, respectively). Multivariate analysis showed that the ER Allred score and cell component of ER-HER2+ cells without HER2- cells were independent predictors of pCR (p = 0.0055 and 0.0081, respectively). In cohort B, posttreatment Ki67, but not pCR, was a prognostic factor of DFS and OS (p = 0.028 and 0.017, respectively). The prognostic value of combined posttreatment Ki67 and pCR was superior to that of either alone. Combined pCR and posttreatment Ki67 had an independent prognostic value for DFS and OS (p = 0.0068 and 0.0101, respectively). CONCLUSIONS: In ER+HER2+ breast cancer, the presence of ER-HER2+ cells without HER2- cells was independently associated with pCR. Combined posttreatment Ki67 and pCR can be more precise in predicting prognosis than pCR alone.

Prospective randomized phase II study determines the clinical usefulness of genetic biomarkers for sensitivity to primary chemotherapy with paclitaxel in breast cancer.

In patients with breast cancer, taxane as well as anthracycline play central roles in systemic chemotherapy. By evaluating the pathological response, we can gauge sensitivity to primary chemotherapy. However, biomarkers that would predict a response to taxane have not yet been established. We conducted a prospective randomized trial to evaluate whether selecting patients using sensitivity testing based on the gene expression of the tumor might enhance the probability of the pathological response. Five genes were identified as biomarkers derived from a microarray of DNA gene profiles from microdisected breast tumors. In the experimental arm (B1), 12 cycles of weekly paclitaxel, 80 mg/m(2) , were preoperatively given when the sensitivity test was positive and therefore judged to be sensitive to paclitaxel. When the test was negative, meaning insensitive to paclitaxel, four cycles of FEC100 were given (arm B2). In the control arm (A), paclitaxel was administered weekly without the use of the sensitivity test. A total of 92 patients were enrolled and 86 patients were analyzed. The pathological response rate (pRR) of each arm was 36.4% in B1 (expected sensitive to paclitaxel), 21.1% in A (control) and 12.5% in B2, respectively. Weekly paclitaxel-treated patients selected by the sensitivity test did not enhance the pRR. The study failed to validate sensitivity testing using five gene expressions for primary chemotherapy with paclitaxel in patients with breast cancer. However, this study suggests that a randomized phase II study is a robust tool for obtaining a rapid conclusion on the usefulness of biomarkers and could be the foundation for further large clinical trials.