Analysis of prognosis in different subtypes of invasive lobular carcinoma using the Japanese National Cancer Database-Breast Cancer Registry.

PURPOSE: Many studies have shown that the prognosis of invasive lobular carcinoma (ILC) is better than that of invasive ductal carcinoma (IDC). However, both disorders exhibit different prognoses according to molecular subtype, and the prognosis of ILC subtypes might depend on their hormone receptor positivity rate. This study clarified the prognosis of ILC and IDC in each subtype and examined the effectiveness of adjuvant chemotherapy (CT) in luminal ILC. METHODS: We planned the analysis using data from the Breast Cancer Registry in Japan. Because it was presumed that there are differences in characteristics between ILC and IDC, we created matched cohorts using exact matching to compare their prognoses. We compared the prognosis of ILC and IDC for each subtype. We also compared the prognosis of luminal ILC between the CT and non-CT groups. RESULTS: For all subtypes, the disease-free survival (DFS) and overall survival (OS) of ILC were poorer than those of IDC. In the analysis by each subtype, no statistically significant difference was found in DFS and OS in luminal human epidermal growth factor 2 (HER2), HER2, and triple-negative cohorts; however, luminal ILC had significantly poorer DFS and OS than luminal IDC. The CT effects on the prognosis of luminal ILC were greater in more advanced cases. CONCLUSION: Luminal ILC had a poorer prognosis than luminal IDC, contributing to the worse prognosis of ILC than that of IDC in the overall cohort. Different therapeutic approaches from luminal IDC are essential for a better prognosis of luminal ILC.

The Absence of Cancer in the Location of a Breast Tissue Marker After Neoadjuvant Chemotherapy may Predict Pathological Complete Response with High Accuracy: Results from a Phase II Trial.

BACKGROUND: It is difficult to determine pathological complete response (pCR) before surgery in clinical complete response (cCR) cases by imaging alone. We designed a prospective study to evaluate whether a breast tissue marker placed in a tumor before neoadjuvant chemotherapy (NAC) can predict a pCR, possibly removing the need for surgery. METHODS: We recruited patients with primary invasive breast cancer assigned to undergo curative surgery and possible NAC. A breast marker (UltraClip®) was placed in the primary tumor before standard NAC. We evaluated the probability of no cancer in the marker but cancer in removed specimens from a cCR group. RESULTS: A total of 102 patients were enrolled. Patients were categorized by cancer stage and subtypes. Seventy-two patients (70.6%) received standard NAC; 23 (34.3%) attained cCR, of whom pCR was obtained in 12 (52.2%). The probability of no cancer in the marker's location but cancer in the removed specimens was 4.3% (95% confidence interval, 0.1-21.9). The false-negative rate was 9.1% (1/11), and the negative predictive value was 92.3% (12/13). In only one case, no cancer was found in the marker's location, but cancer cells were present in the removed specimen. CONCLUSIONS: The absence of cancer in the location of a breast tissue marker after NAC predicted pCR with high accuracy. Therefore, the rebiopsy of a marker's location might mean surgery is unnecessary.

Satisfaction survey on a preoperative explanation method using three-dimensional breast imaging for breast cancer patients considering breast-conserving surgery.

PURPOSE: Although one of the essential factors in surgical shared decision-making is the body image, the breast morphology after breast-conserving surgery is particularly difficult to explain in a uniform manner due to large individual differences. METHODS: Patients with breast cancer eligible for breast-conserving surgery (BCS) were recruited between June 2020 and October 2021. We surveyed the patients' satisfaction with our method of explaining the likely breast morphology after BCS using three-dimensional (3D) breast imaging in the form of a questionnaire. RESULTS: A total of 162 patients were enrolled, and 137 (84.6%) answered the questionnaire. One hundred and sixteen patients (84.6%) answered that they were very satisfied or satisfied with our explanation method, and 100 (73.0%) patients were very satisfied or satisfied with the 3D breast imaging. Some patients answered that 3D breast imaging helped them prepare for BCS, or on the contrary, made them choose mastectomy with breast reconstruction because the deformation likely with BCS was considered unacceptable. Only a few patients who underwent BCS felt that their postoperative morphology was more deformed than the preoperatively imagined one. CONCLUSION: Our results suggest that our preoperative explanation method using 3D breast imaging was useful for shared decision-making.

Compression therapy using surgical gloves does not prevent paclitaxel-induced peripheral neuropathy: results from a double-blind phase 2 trial.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect of paclitaxel (PTX). There is no known prophylactic measure, although there are some reports of prevention with compression therapy using surgical gloves. On account of its predominantly subjective symptoms, it is difficult to exclude bias when assessing for CIPN. In this study, we assessed the effectiveness of the same procedure for the prevention of paclitaxel-induced PN based on a double-blind study design. METHODS: The patients with early and recurrent breast cancer (with no prior PTX exposure) initiating weekly chemotherapy with PTX 80 mg/m2 were enrolled. Each patient donned two gloves on each hand at every PTX infusion. Two one-size-smaller gloves were donned on one hand (study side) and two normal-size gloves were donned on the other hand (control side) during 90 min from 30 min before the infusion to 30 min after the end of the infusion. Study side are blind for both patients and assessing physicians according to determination of the study side by research nurses in the chemotherapy unit. The primary outcome was the difference in the frequency of CIPN (motor/sensory) determined by the physician using the common terminology criteria for adverse events (CTCAE v4.0), with an evaluation at each cycle of PTX infusion. McNemar test was used to assess the primary outcome. RESULTS: Between July 2017 and November 2018, 56 patients were enrolled and 49 patients were evaluated. Overall, Grade ≥ 2 PN (sensory) was observed in 30.6 and 36.7% in the study and control sides, respectively (McNemar p = 0.25). PN (motor) was observed in 4.1 and 6.1% in the study and control sides, respectively (McNemar p = 1.0). CONCLUSION: Surgical glove compression therapy showed no statistically significant effect on the incidence of PTX-induced PN. TRIAL REGISTRATIONS: This study was registered with the University Hospital Medical Information Network (UMIN) Clinical Trials Registry managed by the National University Hospital Council of Japan ( UMIN000027944 ). Registered 26 June 2017.

Differences in baseline risk estimated by physicians and patients with early breast cancer.

BACKGROUND: Physicians recommend adjuvant therapy to patients based on baseline risk. A common recognition for baseline risk between patients and physicians is critical for successful adjuvant therapy. We prospectively investigated the differences in estimated baseline risk between physicians and patients with early breast cancer. METHODS: This analysis was performed at a single institution in Japan. Early breast cancer patients over 18 years old were enrolled after surgery. After explaining the pathological results, physicians asked each patient about an estimated baseline risk. Differences in estimated baseline risk were defined as the baseline risk estimated by patients minus the baseline risk estimated by physicians. The primary endpoint was that the number of patients who estimate baseline risk higher than physicians was higher than those who estimate a lower baseline risk. The secondary endpoints were differences in estimated baseline risk by stage, subtype and the influence of patient factors to differences in estimated baseline risk. RESULTS: From July 2017 to December 2018, 262 patients were enrolled. Among the 262 patients, 190 estimated a higher baseline risk than physicians, 53 estimated a lower baseline risk and 19 estimated the same. Overall, patients estimated a significantly higher baseline risk than physicians (P < 0.001). Differences in estimated baseline risk was significantly smaller in patients who knew the term 'baseline risk' than patients who did not (P = 0.0037). Differences in estimated baseline risk were also significantly smaller in patients with stage II breast cancer than patients with stage I (P = 0.0239). However, there were no statistically significant differences of differences in estimated baseline risk according to other factors. CONCLUSIONS: Patients with early breast cancer estimated a significantly higher baseline risk than physicians. Physicians should accurately explain baseline risk to patients for shared decision making.

The significance of biopsy scar excision at the time of skin- or nipple-sparing mastectomy with immediate breast reconstruction.

BACKGROUND: Neoplastic seeding (NS) can occur after tissue biopsy, which is a clinical issue especially in mastectomy with immediate reconstruction. This is because postoperative radiation is not usually given and local recurrence of preserved skin flap may increase. The purpose of this study is to investigate the importance of preoperative evaluation of NS and the validity of biopsy scar excision. PATIENTS AND METHODS: We retrospectively analysed 174 cases of mastectomy with immediate breast reconstruction. The primary endpoint is the frequency of clinical and pathological NS and the secondary endpoint is the problem of excision of needle biopsy site. RESULTS: Three cases (1.7%) had preoperative clinical findings of NS. Pathological examination revealed NS in all three cases. Biopsy scars could be excised in 115 cases among 171 cases without clinical NS. Pathological NS was found in 1 of 66 (1.5%) cases of which pathological examination was performed. Biopsy scars could not be excised in the remaining 56 cases: the biopsy scar could not be identified in 41 cases, and there was concern about a decrease in flap blood flow after excision in 15 cases. In 12 of these 15 cases, the scars were close to the skin incision; excision of these scars might have triggered skin necrosis between the incision and the biopsy scar excision site. No postoperative complications were observed. CONCLUSIONS: It is important to preoperatively evaluate clinical NS, and biopsy scars should be excised in clinical NS cases. Even in cases without clinical NS, biopsy scar excision should be considered. It is also important to perform a biopsy in consideration of the incision design for reconstructive surgery.

Patient-reported outcomes and objective assessments with arm measurement and bioimpedance analysis for lymphedema among breast cancer survivors.

PURPOSE: Lymphedema (LE) decreases the quality of life of breast cancer patients. Objective quantification of PRO may improve the discordance between patient-reported outcomes (PROs) and objective assessments of LE by establishing a standard follow-up for LE. This study determined the prevalence of subjective and objective LE and evaluated the correlation between objective assessment and PRO of LE in primary breast cancer patients undergoing breast and axilla surgery. METHODS: Breast cancer patients who underwent sentinel lymph node biopsy (SN) or axillary lymph node dissection (ALND) more than 1 year after surgery were enrolled. We prospectively evaluated LE using the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) and two objective assessments (arm circumference and bioimpedance) and analyzed their correlations. RESULTS: Between November 2018 and January 2019, 631 patients (SN; n = 415, ALND; n = 216) were enrolled. The median age, body mass index, and duration from surgery was 56 years, 21.9 kg/m2, and 3.8 years, respectively. The prevalences of subjective and objective LE were 4.1% and 1.4% in the SN group and 51.8% and 24.1% in the ALND group, respectively. The objective assessments were weakly positively correlated with PRO-CTCAE. Arm circumference measurement correlated better than bioimpedance overall and was most strongly correlated with "frequency" (r = 0.485, p < 0.01). CONCLUSIONS: LE occurred in few SN patients. The prevalence of subjective LE was higher than that of objective LE. Arm circumference measurements better reflected PRO than did bioimpedance. These results underscore the limitation of LE detection by subjective or objective methods alone.

Impact of BMI for clinical outcomes in Japanese breast cancer patients.

OBJECTIVE: The relationship between the body mass index (BMI) at the time of breast cancer diagnosis and the prognosis of breast cancer patients has not yet been clarified. We investigated the impact of obesity for clinical outcomes in Japanese breast cancer patients. METHODS: Women with primary breast cancer operated between 2002 and 2014 were identified. All patients are categorized into four groups according to BMI. The range of BMI is <18.5 kg/m2, from 18.5 to 24.9 kg/m2, 25 to 29.9 kg/m2, >30 kg/m2 in underweight, normal, overweight and obesity groups, respectively. The correlation between BMI and overall survival (OS), breast cancer-specific survival (BCSS) and disease-free survival (DFS) were statistically analyzed. RESULTS: From the database of our institution, we identified 3223 patients. The median follow-up period was 57 months (1-149). We categorized 2257 (70.0%), 318 (9.9%), 545 (16.9%) and 103 (3.2%) patients into normal, underweight, overweight obesity groups respectively. There were189 patients (5.9%) deaths due to breast cancer recurrence (137 patients) and other disease (52 patients). Obesity groups was significantly high compared with normal groups for OS (adjusted HR, 2.43; 95% CI, 1.38-4.28; P < 0.001), BCSS (adjusted HR, 2.73; 95% CI, 1.15-6.44; P = 0.02) and DFS (adjusted HR, 1.83; 95% CI, 1.11-3.02; P = 0.017) by multivariate analysis. Especially, OS (adjusted HR, 4.87; 95% CI, 2.15-11.04; P < 0.001), BCSS (adjusted HR, 4.51; 95% CI, 1.52-13.34; P < 0.001) and DFS (adjusted HR, 4.87; 95% CI, 1.02-4.89; P = 0.04) were statistically insignificant in postmenopausal ER-positive breast cancer patients. CONCLUSION: Obesity might be risk factor for OS, BCSS and DFS, especially postmenopausal ER-positive women.

A single-arm, phase 2 study of steroid-containing mouthwash for the prevention of everolimus-associated stomatitis in multiple tumor types.

BACKGROUND: Everolimus is a mammalian target of rapamycin inhibitor used in the treatment of multiple tumor types, and its most common toxicity, stomatitis, can affect patient quality of life. Recent studies in breast cancer have supported the efficacy of steroid mouthwash for the prevention of everolimus-associated stomatitis. However, a few studies have been reported to date, and none have examined this effect in other tumor types. METHODS: This single-arm phase 2 study was designed to evaluate the efficacy of steroid-containing mouthwash for the prevention of stomatitis in patients with multiple tumor types receiving everolimus. The primary outcome was incidence of grade ≥ 2 stomatitis at 8 weeks of everolimus with steroid-containing mouthwash prophylaxis. We also assessed the stability of steroid-containing mouthwash components. RESULTS: Twenty-nine patients were evaluated, of which 76% had breast cancer and 24% had neuroendocrine tumors originating in the lung, gastrointestinal tract, pancreas, or of unknown primary origin. Grade ≥ 2 stomatitis incidence at 8 weeks was 28.1% (90% CI 16.2-46.1); the higher confidence limit exceeded the prespecified threshold of 30%. No patients developed grade ≥ 3 stomatitis. Most stomatitis occurred behind the oral cavity, with no lesions observed on the lips or floor of the mouth. CONCLUSIONS: Our findings did not support a prophylactic effect of steroid-containing mouthwash on everolimus-associated stomatitis. Given the needs of prevention of everolimus-associated stomatitis in various tumor types, further studies in a larger population using a randomized controlled trial design are, therefore, required to confirm the efficacy of steroid-containing mouthwash.

The overall survival of breast cancer patients without adjuvant therapy.

PURPOSE: There are little data regarding the overall survival (OS) of patients without adjuvant systemic therapy, because most patients have been subject to standardized systemic therapies. We evaluated the baseline risk to facilitate making decisions about adjuvant therapy. PATIENTS AND METHODS: A total of 1835 breast cancer patients who did not receive adjuvant systemic therapy between 1964 and 1992 were retrospectively evaluated. We investigated the 10-year disease-free survival (DFS) and OS according to the number of metastatic lymph nodes, pathological T classification, stage, and estrogen receptor (ER) status. RESULTS: Survival curves showed that as the number of metastatic lymph nodes, pathological T classification, and staging increased, the 10-year OS and DFS decreased. In univariate and multivariable analyses, the number of metastatic lymph nodes was significantly associated with the DFS and OS, while in a univariate analysis, the pathological T classification and stage were significantly associated with the DFS and OS. ER positivity was a good prognostic factor for the 5-year DFS. However, between 6 and 7 years after surgery, ER negativity was a better prognostic factor than ER positivity. CONCLUSION: We showed survival rates of patients without adjuvant therapy according to TNM classification and ER status. This information can aid in treatment selection for doctors and patients through a shared decision-making approach.

Acute phase dynamics of circulating tumor cells after paclitaxel and doxorubicin chemotherapy in breast cancer mouse models.

PURPOSE: Circulating tumor cells (CTCs) can provide a potentially minimal invasive source for monitoring chemotherapeutic effects. However, detailed in vivo dynamics of CTC after chemotherapy remain largely unknown. METHODS: We monitored CTC number and morphology early after chemotherapy using a newly developed cytology-based CTC detection device and triple-negative breast cancer mouse CTC models with spontaneous lung metastatic potential. RESULTS: Paclitaxel inhibited cell growth of breast cancer cells by mainly G2/M cell cycle arrest and partly apoptosis, whereas doxorubicin inhibited cell growth mainly by apoptosis and partly G2 cell cycle arrest in vitro. The number of CTCs was significantly increased 3-10 days after paclitaxel and doxorubicin chemotherapy and decreased thereafter in two mouse CTC models. The transiently increased CTCs early post-chemotherapy consisted of not only G2/M arrested cells (apoptotic cells), but also morphologically near-intact live cells. This heterogeneous cell population of CTCs was similar to that of primary tumor tissue after chemotherapy. CONCLUSIONS: These results indicate that CTCs can be mobilized from the primary tumor in rapid response to chemotherapy and suggest the possibility that CTC monitoring from both numerical and morphological viewpoints early after chemotherapy using a cytology-based CTC detection device would be a useful diagnostic tool for predicting drug sensitivity/resistance in preclinical and clinical setting.

Occult breast cancer may originate from ectopic breast tissue present in axillary lymph nodes.

PURPOSE: Occult breast cancer (OBC) is classified as a carcinoma of unknown primary, and involves axillary lymphadenopathy and is histologically consistent with metastatic breast cancer. OBC has been conventionally considered as a metastatic lymph node lesion, the origin of which is an undetectable breast tumor. Therefore, OBC patients would usually have undergone axillary lymph node dissection, and mastectomy or whole breast radiotherapy (WBRT). However, majority of OBC reports have been based on cases that were diagnosed during a period when diagnostics was still relatively primitive, and when magnetic resonance imaging was not yet a standard preoperative assessment. Therefore, there have been many false negatives in the breast based on preoperative assessment. METHODS: We herein hypothesize that the origin of OBC is ectopic breast tissue present in axillary lymph nodes (ALNs). If our hypothesis is true, mastectomy and WBRT may be unnecessary for OBC patients. RESULTS: Our hypothesis is supported by several findings. First, advances in radiological imaging have suggested that a primary breast tumor is absent in OBC patients. Second, proliferative breast lesions arising from ectopic breast present in ALNs have been reported. Lastly, cellular subtypes in OBC based on immunohistochemistry are of various types including ordinary breast cancer and the prognosis is not worse than stage II breast cancer. CONCLUSION: It is important to distinguish between "primary" OBC in ALNs and "metastatic" OBC from micro-primary breast tumor. Further studies are required to determine if omission of mastectomy and WBRT is acceptable.

The investigation study using a questionnaire about the employment of Japanese breast cancer patients.

BACKGROUND: Breast cancer is the most common cancer among women, and its survival rate has improved. As the number of cancer survivors increases, it is important to support their social comeback during and after treatment. METHODS: Questionnaires were distributed to breast cancer patients treated in Aichi Cancer Center Hospital between June and November 2014. Responders were categorized according to adjuvant therapy (Group A: none, Group B: endocrine therapy, Group C: chemotherapy), or if they had advanced or recurrent breast cancer (Group D). RESULTS: A total of 279 patients returned questionnaires (62, 79, 92 and 46 patients in Groups A, B, C and D, respectively). In adjuvant treatment groups, 43 patients (18.5%) quit their job during or after treatment. Most patients had quit their jobs at the time of diagnosis (7.5%), followed by those undergoing chemotherapy (5.6%) and those at the time of operation (4.9%). Quit rate from the workplace in which patients worked at the time of diagnosis was highest in Group C (30%), followed by Group B (20%) and Group A (13%). At the time of operation, 127 patients (57%) were absent from work. In Group D, 16 patients (35%) quit their job during treatment. Rates for patients currently working who had anxiety were 62, 30, 26 and 9% in Groups D, C, B and A, respectively. CONCLUSIONS: In adjuvant treatment groups, in which quit rate was highest at the time of diagnosis, consultation about working is necessary immediately after diagnosis. Patients treated most heavily had higher quit rates and experienced more anxiety about working.

Feasibility of dose-dense epirubicin and cyclophosphamide with subcutaneous pegfilgrastim 3.6 mg support: a single-center prospective study in Japan.

BACKGROUND: Dose-dense chemotherapy consisting of a combination of epirubicin and cyclophosphamide (EC) improves the survival of patients with breast cancer. Although pegfilgrastim was used at a subcutaneous dose of 6.0 mg in a pivotal study of dose-dense EC treatment, pegfilgrastim at a dose of 3.6 mg has been approved in Japan. We have assessed the feasibility of dose-dense EC treatment supported with a 3.6 mg dose of pegfilgrastim by evaluating the relative dose intensity (RDI) and safety of the treatment, together with measuring the pegfilgrastim concentrations remaining on the day of starting the next cycle of chemotherapy. METHODS: Patients with primary breast cancer received a total of 4 cycles of dose-dense EC treatment every 2 weeks, together with a subcutaneous injection of 3.6 mg pegfilgrastim on the day after chemotherapy. The serum granulocyte colony-stimulating factor (G-CSF) concentrations were measured on the 15th day of every chemotherapy cycle. RESULTS: From March 2015 through to July 2016, a total of 51 patients (median age 51 years; range 33-73 years) were studied. The mean RDI was 95.2% (range 60.0-100%). Although most adverse events were consistent with those reported in previous studies, pneumocystis pneumonia developed in two patients during the following course of docetaxel treatment. The median serum G-CSF concentration was 92.5 (range 30.4-440) pg/ml. CONCLUSIONS: With support provided by pegfilgrastim injection at a dose of 3.6 mg, dose-dense EC is feasible and associated with maintenance of a high RDI. There was no clinically significant accumulation of serum G-CSF concentrations associated with the use of a 3.6 mg dose of pegfilgrastim at 2-week intervals.

Comparison of clinical outcomes between luminal invasive ductal carcinoma and luminal invasive lobular carcinoma.

BACKGROUND: The pathological and clinical features of invasive lobular carcinoma (ILC) differ from those of invasive ductal carcinoma (IDC). Several studies have indicated that patients with ILC have a better prognosis than those with ductal carcinoma. However, no previous study has considered the molecular subtypes and histological subtypes of ILC. We compared prognosis between IDC and classical, luminal type ILC and developed prognostic factors for early breast cancer patients with classical luminal ILC. METHODS: Four thousand one hundred ten breast cancer patients were treated at the Aichi Cancer Center Hospital from 2003 to 2012. We identified 1,661 cases with luminal IDC and 105 cases with luminal classical ILC. We examined baseline characteristics, clinical outcomes, and prognostic factors of luminal ILC. RESULTS: The prognosis of luminal ILC was significantly worse than that of luminal IDC. The rates of 5-year disease free survival (DFS) were 91.9% and 88.4% for patients with luminal IDC and luminal ILC, respectively (P = 0.008). The rates of 5-year overall survival (OS) were 97.6% and 93.1% for patients with luminal IDC and luminal ILC respectively (P = 0.030). Although we analyzed prognosis according to stratification by tumor size, luminal ILC tended to have worse DFS than luminal IDC in the large tumor group. In addition, although our analysis was performed according to matching lymph node status, luminal ILC had a significantly worse DFS and OS than luminal IDC in node-positive patients. Survival curves showed that the prognosis for ILC became worse than IDC over time. Multivariate analysis showed that ILC was an important factor related to higher risk of recurrence of luminal type breast cancer, even when tumor size, lymph node status and histological grade were considered. CONCLUSIONS: Luminal ILC had worse outcomes than luminal IDC. Consequently, different treatment approaches should be used for luminal ILC than for luminal IDC.

The frequency of low HER2 expression in breast cancer and a comparison of prognosis between patients with HER2-low and HER2-negative breast cancer by HR status.

PURPOSE: The DESTINY-Breast04 clinical trial is currently investigating whether trastuzumab deruxtecan (T-DXd) is effective in HER2-low as well as HER2-positive breast cancer. This highlights the interest in treatment strategies for patients with HER2-low breast cancer. The current study was therefore designed to determine the frequency of HER2-low among all breast cancers, and to compare the prognosis of HER2-low patients with that of HER2-negative patients. METHODS: We retrospectively reviewed the biological data from 4,918 of 4,977 primary breast cancer patients who attended our institute. We quantified the overall frequency of breast cancer patients with a new HER2-low subtype that was defined by an immunohistochemistry score of IHC1 + or IHC2 + /ISH-. We then compared the clinical characteristics and prognosis of HER2-low patients with that of patients who did not have HER2 amplification (HER2-0). RESULTS: Low HER2 expression was found in 3169 (64.4%) patients; 2860 (58.1%) were HR-positive and 309 (6.3%) were HR-negative. Among HER2-0 patients, 681 (13.9%) were HR-positive and 157 (3.2%) were HR-negative. The HER2-0 group tended to have more poor prognostic factors than the HER2-low group, irrespective of HR status. There were no statistically significant differences between the prognosis of HER2-low and HER2-0 patients, regardless of HR status. However, patients in the HER2-low group tended to have better prognosis than those in the HER2-0 group. CONCLUSION: HER2-low patients did not have a significantly different prognosis than HER2-0 patients, regardless of HR status. However, we should consider tailoring therapies for patients with HRE2-low early breast cancer according to their HR status.

Impact of adjuvant endocrine therapy on prognosis in small hormone receptor-positive, HER2-negative early breast cancer.

BACKGROUND: The efficacy of adjuvant endocrine therapy for hormone receptor-positive breast cancer has been previously established. However, significant adverse events related to endocrine therapy cannot be ignored. T1 breast cancer is expected to have a good prognosis. Therefore, adjuvant endocrine therapy for T1a breast cancer patients is controversial. Thus, in this study, we examined the effect of endocrine therapy on the prognosis of T1N0 hormone receptor-positive, HER2-negative breast cancer patients in each tumor size group, and re-considered the application of endocrine therapy. METHODS: We retrospectively obtained clinical and pathological data from medical records of 7635 patients who underwent surgery for breast cancer at Aichi Cancer Hospital between January 2000 and December 2017. The primary end point of our analysis was disease-free survival (DFS). The secondary end points were distant disease-free survival (DDFS), overall survival (OS), and breast cancer-specific survival (BCSS). The log-rank test, cumulative survival generated curves with Kaplan-Meier methods and the hazard ratio (HR) calculated with a Cox regression model were used to assess the effects of endocrine therapy on prognosis. RESULTS: The 5-year DFS was worse in the non-endocrine therapy (non-ET) group (78%) than the endocrine therapy (ET) group (95%) in the T1c population (p < 0.001, HR 0.25). However, there was no statistically significant difference in DFS between the ET and the non-ET groups in T1a (ET 96% vs non-ET 93%, p = 0.9314, HR 0.94) and T1b (ET 96% vs non-ET 93%, p = 0.1481HR 0.53) breast cancer. The OS, DDFS, and BCSS of the patients also showed that endocrine therapy was associated with improvement of the prognosis in the T1c group, but not in the T1a and T1b groups. CONCLUSIONS: Adjuvant endocrine therapy may be essential for T1c breast cancer patients. In contrast, this therapy should be discussed for T1a and T1b luminal breast cancer patients under some circumstances, such as suffering from adverse events.

Effects of neoadjuvant chemotherapy on operative adverse events and chemotherapy and radiotherapy in patients undergoing immediate breast reconstruction.

BACKGROUND: Immediate breast reconstruction (IBR) has been become a standard treatment for patients with breast cancer undergoing mastectomy. However, whether IBR is appropriate in patients undergoing neoadjuvant chemotherapy (NAC) is still unclear. Therefore, in this study we examined the rates of operative adverse events (AEs), risk factors for operative AEs, and effects on chemotherapy and radiotherapy of IBR with NAC. METHODS: Between January 2012 and March 2018, 593 patients underwent IBR at the Aichi Cancer Center Hospital. We retrospectively obtained clinical data of all these patients from their medical records and identified 56 patients (65 breasts) who had received NAC (NAC group) and 537 patients (568 breasts) who had not (non-NAC group). We compared the rates of operative AEs, risk factors for operative AEs, chemotherapy-related AEs, and duration to radiotherapy between the NAC and non-NAC cohorts. RESULTS: The rate of operative AEs was significantly higher in the NAC than the non-NAC group (35% vs. 22%, p < 0.05). However, axillary lymph node dissection was the most influential risk factor, and NAC was not identified as a risk factor for operative AEs in patients who had undergone IBR. Additionally, there were no statistically significant differences in chemotherapy-related AEs or interval between surgery and postoperative radiotherapy between the NAC and non-NAC groups. CONCLUSIONS: NAC remains likely to contribute to increased postoperative AEs in patients undergoing IBR; however, it does not affect postoperative treatment and IBR is appropriate for patients undergoing NAC.