Efficacy of radiation therapy in Japanese patients with positive margins after breast-conserving surgery.

BACKGROUND: Additional surgical resection is recommended after breast-conserving surgery if the surgical margin is pathologically positive. However, in clinical practice, radiation therapy is sometimes used instead for several reasons. Irradiation may be appropriate for some patients, but real-world data is still insufficient to establish it as standard treatment. We retrospectively investigated the status of local control in patients who received irradiation for positive margins. METHODS: We investigated 85 patients with positive margins after curative partial mastectomy who were treated with irradiation instead of additional excision during the period 2006-2013. The patients received whole-breast irradiation (43.2-50 Gy) using photon beams and additional tumour-bed boost (8.1-16 Gy) using electron beams. Intrabreast tumour recurrence was defined as secondary cancer within the ipsilateral conserved breast. Surgical margin was defined as positive if tumour cell exposure was pathologically confirmed on the margin. RESULTS: Seven patients (8.2%) developed intrabreast tumour recurrence during a mean observation period of 119 months. As to components of positive margin, 76 cases were positive for an intraductal component, of which seven (9.2%) developed intrabreast tumour recurrence. Meanwhile, all nine cases positive for an invasive component were free from intrabreast tumour recurrence. Two of the intrabreast tumour recurrence cases seemed to develop new lesions rather than recurrence, considering tumour location. The cumulative incidence of intrabreast tumour recurrence over 10 years was 6.1%. Limited to true recurrence, intrabreast tumour recurrence incidence was 4.9%. CONCLUSION: Our real-world data supports irradiation as an alternative to additional surgical intervention for positive margins after breast-conserving surgery and offers a basis for further research.

Stromal Ki67 Expression Might be a Useful Marker for Distinguishing Fibroadenoma From Benign Phyllodes Tumor of the Breast.

Background. Fibroadenoma (FA) and benign phyllodes tumor (PT) of the breast often have similar appearances on imaging. While an exact diagnosis of biopsy specimens is required to choose adequate treatment, including surgical procedures, it is sometimes difficult to pathologically differentiate these 2 tumors due to histological resemblances. To elucidate markers for distinguishing FA from benign PT, we analyzed clinical samples immunohistochemically. Methods. We retrospectively investigated 80 breast fibroepithelial lesions. As a discovery set, 60 surgical excision samples (30 FA and 30 benign PT) were examined. Twenty biopsy samples (10 FA and 10 benign PT) were examined as a validation set. To determine targets for immunohistochemistry, we first tested some proteins based on previous reports. As a result, Ki67 was chosen for differentiating FA and PT; thus further examinations were conducted with this protein. Results. Among the proteins examined, stromal Ki67 was significantly higher in PT than in FA. Benign PT had significantly higher stromal Ki67 expression both at random and at hotspots (p < .001 and <.001, respectively). The receiver operating characteristic curve analysis identified 3.5% and 8.5% (at random spots and hotspots, respectively) as the optimal cutoff values of stromal Ki67 for distinguishing between these 2 tumors. In the validation cohort employing needle biopsy specimens, we confirmed that these 2 cutoff values properly classified these 2 tumors (p = .043 and .029, respectively). Conclusion.We revealed that stromal Ki67 might be a potential marker for distinguishing FA from benign PT.

BRCAness of brain lesions reflects a worse outcome for patients with metastatic breast cancer.

PURPOSE: Breast cancer often metastasizes to the central nervous system. Although the prognosis of brain metastases from breast cancer has been considered poor, and systemic therapy has not contributed to an improved prognosis, newer agents are expected to be more effective. BRCAness is defined as the status of homologous recombination deficiency (HRD) in tumor tissue, regardless of the presence of pathogenic germline BRCA1/2 variants. A study employing next-generation sequencing analysis showed that HRD was found relatively frequently in brain metastases of breast cancer patients. However, there have been no studies evaluating BRCAness in brain metastases of breast cancer with more efficient, rapid, and cost-effective methods. METHODS: We retrospectively investigated 17 brain metastases of breast cancer that were surgically resected at our hospital from January 2007 to December 2022. Of these, samples from 15 patients were evaluable for BRCAness by employing multiplex ligation-dependent probe amplification (MLPA) assay. RESULTS: Of the 15 patients, five patients (33%) had tumors with BRCAness. Clinicopathological factors of patients with brain metastases with BRCAness were not statistically different from those of patients who possessed tumors without BRCAness. Patients with brain metastases with BRCAness had shorter overall survival compared to those without BRCAness (BRCAness, median 15 months (95% CI 2-30) vs. non-BRCAness, median 28.5 months (95% CI 10-60); P = 0.013). CONCLUSION: In this study, we evaluated BRCAness in brain metastases of breast cancer with the MLPA method, and found that about one-third of patients had BRCAness-positive tumors. The analysis of BRCAness using MLPA has the potential for practical clinical use.

IgG4-related mastitis characterized by skin thickening of the breast: a case report.

BACKGROUND: IgG4-related diseases are characterized by marked infiltration and IgG4-positive plasma cells and fibrosis, and involve multiple organs. However, IgG4-related mastitis is rare. We report a case of mastitis associated with IgG4-related disease. CASE PRESENTATION: A 78-year-old woman visited our hospital with a complaint of multiple subcutaneous nodules. A biopsy of a dorsal subcutaneous mass was performed but did not yield a definitive diagnosis. However, blood tests showed a high level of IgG4, thus she was referred to the department of collagen disease for further examination. Computed tomography (CT) showed a thickening of the skin of the right breast, and the patient was referred to our department. On physical examination, a large area of thickened skin was observed in the right breast without inflammatory breast cancer-like redness, and no mass was palpable. A needle biopsy was performed on an indistinct hypoechoic area in the breast, and she was diagnosed with mastitis associated with IgG4-related disease. Systemic steroid therapy was then administered and the symptoms of multiple skin nodules and mastitis improved. CONCLUSIONS: We reached the diagnosis based on a biopsy of the mammary gland enabling the patient to begin treatment for IgG4-related disease. This case was characterized by breast skin thickening, which is different from inflammatory breast cancer.

Relationship Between Daily Dose of Everolimus and Treatment Effect in Patients With Luminal HER2-negative Metastatic Breast Cancer.

BACKGROUND/AIM: Everolimus (EVE)-based treatment is an option for hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC), but a predictive marker has not yet been established. The recommended dose of EVE in combination with endocrine therapy is 10 mg/day, but due to adverse effects, patients are frequently forced to reduce the dose. However, the correct maintenance dose to achieve a therapeutic effect is still under debate. Employing real-world data, we examined clinicopathological factors to predict the efficacy of EVE-based treatment, particularly focusing on daily dose intensity (DDI). PATIENTS AND METHODS: Ninety-five patients with MBC who received EVE-based treatment in combination with exemestane during the period from 2014 to 2022 were retrospectively investigated. Doses of EVE were reduced as needed and DDI was calculated with total doses of EVE and the duration of the treatment. RESULTS: Mean time-to-treatment-termination (TTT) was 25.4 weeks. Patients with tumors with a high Ki67 labeling index, low absolute lymphocyte count, and small DDI of EVE had significantly shorter TTT (p=0.006, 0.043, and 0.030, respectively). When patients were categorized based on DDI of EVE, patients with DDI ≤5 mg/day had significantly shorter TTT (p=0.002). There were no correlations between RDI and factors such as age, body weight, and numbers of previous treatments for MBC. CONCLUSION: Maintaining a DDI of at least 5 mg/day seems crucial to achieving a therapeutic effect. Our data might be useful for determining the dosage of EVE in clinical practice.

The Impact of Being Underweight on the Prognosis of Older Patients With Early Breast Cancer.

Background/Aim: The number of older patients with breast cancer has been increasing and a major challenge is to develop optimal treatment strategies for these patients, who often have comorbidities. Obesity is reportedly a poor prognostic factor in breast cancer, however there is limited research on underweight patients. Clarifying the relationship between physique and prognosis may contribute to the establishment of optimal treatment strategies for older patients with breast cancer. Patients and Methods: This retrospective study examined clinicopathological data from a multicenter collaborative database on 1,076 patients aged 70 years or older who had undergone curative surgery. According to the body mass index (BMI), patient physique was defined as underweight (<18.5 kg/m2), normal (18.5-24.9 kg/m2) or obese (≥25 kg/m2). In this study, we explored the relationship between the physique of patients with breast cancer and outcomes. Results: Underweight patients had a significantly lower rate of chemotherapy administration (p=0.017) and a higher rate of presence of other cancer (p=0.022). During the observation period (median of 75.2 months), 133 patients (12%) developed recurrent disease and 131 patients (12%) died. Age, BMI, tumor size, progesterone receptor and the presence of other cancer were independent factors relating to overall survival (p<0.001, p=0.027, p=0.002, p=0.008 and p=0.005, respectively). Patients with a low BMI had a significantly shorter overall survival, but there was no association with disease-free survival in this subset of patients. Conclusion: Overall survival was shorter in underweight older patients with breast cancer. Our data indicate that being underweight should be considered both in treatment decisions and in future studies of outcomes for older patients with breast cancer.

Possible correlation of apical localization of MUC1 glycoprotein with luminal A-like status of breast cancer.

Adjuvant chemotherapy has played a major role in the treatment of hormone receptor-positive breast cancer for many years. To better determine which patient subsets need adjuvant chemotherapy, various gene expression analyses have been developed, but cost-effective tools to identify such patients remain elusive. In the present report, we retrospectively investigated immunohistochemical expression and subcellular localization of MUC1 in primary tumors and examined their relationship to tumor malignancy, chemotherapy effect and patient outcomes. We retrospectively examined three patient cohorts with hormone receptor-positive/human epidermal growth factor receptor 2-negative invasive breast cancer: 51 patients who underwent 21-gene expression analysis (multi-gene assay-cohort), 96 patients who received neoadjuvant chemotherapy (neoadjuvant chemotherapy-cohort), and 609 patients whose tumor tissue was used in tissue-microarrays (tissue-microarray-cohort). The immunohistochemical staining pattern of the anti-MUC1 monoclonal antibody, Ma695, was examined in cancer tissues, and subcellular localization was determined as apical, cytoplasmic or negative. In the multi-gene assay-cohort, tumors with apical patterns had the lowest recurrence scores, reflecting lower tumor malignancy, and were significantly lower than MUC1-negative tumors (P = 0.038). In the neoadjuvant chemotherapy-cohort, there was no correlation between MUC1 staining patterns and effects of chemotherapy. Finally, in the tissue-microarray-cohort, we found that patients with apical MUC1 staining patterns had significantly longer disease-free-survival and overall survival than other patterns (P = 0.020 and 0.039, respectively). Our data suggest that an apical MUC1 staining pattern indicates luminal A-likeness. Assessment of the subcellular localization of MUC1 glycoprotein may be useful for identifying patients who can avoid adjuvant chemotherapy.

Acute myocarditis during adjuvant therapies for breast cancer: a case report.

BACKGROUND: With the improvement of optimal perioperative drug therapy for breast cancer patients, physicians now have to treat the adverse effects and comorbidities associated with long-term treatments. We report a case who suffered cardiac arrest due to acute myocarditis developed after initiation of adjuvant treatment. CASE PRESENTATION: After completing preoperative chemotherapy and undergoing curative surgery for right breast cancer, a 46-year-old female patient started adjuvant tamoxifen and resumed trastuzumab. Two months later, she complained fever and dyspnea. Blood tests showed a marked increase in hepatic enzymes, and the patient was rushed to our emergency room on suspicion of drug-induced liver injury. In the emergency room, the patient went into cardiac arrest shortly after tachycardia with ST-segment elevation appeared on the monitored electrocardiogram. Resuscitation was started immediately and tracheal intubation, intra-aortic balloon pumping, and extracorporeal membrane oxygenation were started. Coronary angiography results were negative for ischemic heart disease. A diagnosis of fulminant myocarditis was made and steroid pulse therapy and immunoglobulin therapy were started. After the start of treatment, the symptoms of heart failure improved steadily and the patient was discharged on the 28th day. Histological findings of the myocardial biopsy revealed degeneration and necrosis of myocardial cells with marked lymphocytic infiltration, consistent with the histology of lymphocytic myocarditis. Serum cytomegalovirus, coxsackie B virus and adenovirus antibodies were all elevated and these findings were consistent with acute viral myocarditis. CONCLUSIONS: We report a case with strong indications for therapy-induced liver damage, who was ultimately diagnosed with acute viral myocarditis and successfully treated with multidisciplinary therapy. We believe that our findings would be useful for other clinicians in managing similar patients.

High platelet-to-lymphocyte ratios in triple-negative breast cancer associates with immunosuppressive status of TILs.

BACKGROUND: Rating lymphocytes (TILs) are a prognostic marker in breast cancer and high TIL infiltration correlates with better patient outcomes. Meanwhile, parameters involving immune cells in peripheral blood have also been established as prognostic markers. High platelet-to-lymphocyte ratios (PLRs) and neutrophil-to-lymphocyte ratios (NLRs) are related to poor outcomes in breast cancer, but their mechanisms remain unknown. To date, TILs and these parameters have been examined separately. METHODS: We investigated the relationship between TILs and the peripheral blood markers, PLR and NLR, in the same patients, using surgical specimens from 502 patients with invasive breast carcinoma without preoperative chemotherapy. For analysis of triple-negative breast cancer (TNBC) patient outcomes, 59 patients who received preoperative chemotherapy were also examined. For immune cell profiling, multiplexed fluorescent immunohistochemistry (mfIHC) of CD3, CD4, CD8, FOXP3 and T-bet, was conducted. RESULTS: A positive correlation between PLR and TIL was observed in TNBC (P = 0.013). On mfIHC, tumors in patients with high PLR and NLR contained more CD3+CD4+FOXP3+ T-cells (P = 0.049 and 0.019, respectively), while no trend was observed in CD8+ T-cells. TNBC patients had different patterns of outcomes according to TIL and PLR, with the TIL-high/PLR-low group having the lowest rate of disease relapse and death, and the longest distant metastasis-free and overall survivals, while the TIL-low/PLR-high group had the shortest survivals. CONCLUSIONS: Our data suggest that the combination of PLR with TIL assessment may enable more accurate prediction of patient outcomes with TNBC.

Absolute lymphocyte count decreases with disease progression and is a potential prognostic marker for metastatic breast cancer.

PURPOSE: Peripheral blood parameters such as the neutrophil-to-lymphocyte ratio (NLR) are prognostic markers for breast cancer patients. For instance, patients with a high NLR have a poor prognosis. Meanwhile, high absolute lymphocyte count (ALC) is reportedly a predictive factor for some chemotherapies. However, the underlying mechanisms behind how these markers relate to patient outcomes and how these markers change during the clinical course of patients with metastatic breast cancer (MBC) remains unknown. METHODS: We retrospectively investigated 156 patients who were treated for MBC and eventually transitioned to best supportive care (BSC) at our hospital between January 2017 and December 2021. Changes in peripheral blood parameters during MBC treatments and their association with patient outcomes were examined. RESULTS: From the time of MBC diagnosis (baseline) through to the transition to BSC, ALC became significantly lower, while the NLR and platelet-to-lymphocyte ratio (PLR) became significantly higher (p < 0.001 for all). This association was independent of hormone receptor status. Cox proportional hazard modeling found patients with hormone receptor-negative and a lower baseline ALC had a significantly shorter overall survival (p = 0.030 and p = 0.019, respectively). CONCLUSION: We observed that peripheral blood markers gradually changed with MBC disease progression. Our data suggest that baseline ALC may be a potential prognostic marker after recurrence.

Tamoxifen-resistant breast cancer cells exhibit reactivity with Wisteria floribunda agglutinin.

Glycosylation is one of the most important post-translational modifications of cell surface proteins involved in the proliferation, metastasis and treatment resistance of cancer cells. However, little is known about the role of glycosylation as the mechanism of breast cancer cell resistance to endocrine therapy. Herein, we aimed to identify the glycan profiles of tamoxifen-resistant human breast cancer cells, and their potential as predictive biomarkers for endocrine therapy. We established tamoxifen-resistant cells from estrogen receptor-positive human breast cancer cell lines, and their membrane-associated proteins were subjected to lectin microarray analysis. To confirm differential lectin binding to cellular glycoproteins, we performed lectin blotting analyses after electrophoretic separation of the glycoproteins. Mass spectrometry of the tryptic peptides of the lectin-bound glycoproteins was further conducted to identify glycoproteins binding to the above lectins. Finally, expression of the glycans that were recognized by a lectin was investigated using clinical samples from patients who received tamoxifen treatment after curative surgery. Lectin microarray analysis revealed that the membrane fractions of tamoxifen-resistant breast cancer cells showed increased binding to Wisteria floribunda agglutinin (WFA) compared to tamoxifen-sensitive cells. Glycoproteins seemed to be responsible for the differential WFA binding and the results of mass spectrometry revealed several membrane glycoproteins, such as CD166 and integrin beta-1, as candidates contributing to increased WFA binding. In clinical samples, strong WFA staining was more frequently observed in patients who had developed distant metastasis during tamoxifen treatment compared with non-relapsed patients. Therefore, glycans recognized by WFA are potentially useful as predictive markers to identify the tamoxifen-resistant and relapse-prone subset of estrogen receptor-positive breast cancer patients.

Comparison of tumors with HER2 overexpression versus HER2 amplification in HER2-positive breast cancer patients.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2)-positive tumors are defined by protein overexpression (3+) or gene amplification using immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH), respectively. HER2-positive tumors have historically included both IHC(3+) and IHC(2+, equivocal)/FISH(+) tumors and received the same treatment. Differences in biology between these two tumor types, however, are poorly understood. Considering anti-HER2 drugs bind directly to HER2 protein on the cell surface, we hypothesized anti-HER2 therapies would be less effective in IHC(2+)/FISH(+) tumors than in IHC(3+) tumors, leading to differences in patient outcomes. METHODS: A total of 447 patients with HER2-positive invasive carcinoma who underwent curative surgery were retrospectively investigated. HER2 status was assessed in surgical specimens, except in patients who received neo-adjuvant chemotherapy, where biopsy specimens were employed. RESULTS: Age, tumor size, lymph node status and ER status were independent factors relating to disease-free-survival, but no difference was observed between IHC(3+) and IHC(2+)/FISH(+) tumors. Kaplan-Meier analysis found patient outcomes did not differ, even after stratifying into those that did (n = 314), or did not (n = 129), receive chemotherapy with anti-HER2 drugs. In 134 patients who received NAC, pathological complete response rates in IHC(3+) and IHC(2+)/FISH(+) tumors were 45% and 21%, respectively. Survival after developing metastasis was significantly shorter in the IHC(2+)/FISH(+) group. CONCLUSIONS: The prognosis of patients with IHC(2+)/FISH(+) tumors did not differ from IHC(3+) tumors. However, the significance of HER2 protein overexpression in relation to treatment response remains unclear and warrants further investigations.

Is adjuvant chemotherapy necessary in older patients with breast cancer?

BACKGROUND: Due to the lack of clinical trials on the efficacy of chemotherapy in older patients, an optimal treatment strategy has not been developed. We investigated whether adjuvant chemotherapy could improve the survival of older patients with breast cancer in Japan. METHODS: We retrospectively analyzed data of patients with breast cancer aged ≥ 70 years who underwent breast cancer surgery in eight hospitals between 2008 and 2013. Clinical treatment and follow-up data were obtained from the patients' medical electric records. RESULTS: A total of 1095 patients were enrolled, of which 905 were included in the initial non-matched analysis. The median age and follow-up period were 75 (range 70-93) and 6.3 years, respectively. Of these patients, 127 (14%) received adjuvant chemotherapy (Chemo group) while the remaining 778 (86%) did not (Control group). The Chemo group was younger (mean age in years 73 vs 76; P < 0.0001), had a larger pathological tumor size (mean mm 25.9 vs 19.9; P < 0.0001), and more metastatic axillary lymph nodes (mean numbers 2.7 vs 0.7; P < 0.0001) than the Control group. The disease-free survival (DFS) and overall survival (OS) did not differ significantly between the two groups (P = 0.783 and P = 0.558). After matched analyses, DFS was found to be significantly prolonged with adjuvant chemotherapy (P = 0.037); however, OS difference in the matched cohort was not statistically significant (P = 0.333). CONCLUSION: The results showed that adjuvant chemotherapy was associated with a reduced risk of recurrence, but survival benefits were limited.

Clinicopathological Features Related to the Efficacy of CDK4/6 Inhibitor-Based Treatments in Metastatic Breast Cancer.

BACKGROUND: Resistance to endocrine therapy has been a major obstacle in the management of hormone receptor (HR)-positive metastatic breast cancer (MBC). Meanwhile, a number of treatments are available to such patients, and physicians often encounter difficulties in choosing the most appropriate treatments for individual patients. The combination of CDK 4/6 inhibitors (CDKi) and endocrine therapy has now become a standard treatment for HR-positive and human epidermal growth factor receptor 2 (HER2)-negative MBC. However, no predictive markers for CDKi-based treatments have been established. Considering their side effects and the financial burden on patients, identifying such markers is crucial. METHODS: Clinicopathological features of 107 patients with HR-positive HER2-negative MBC, who received CDKi-based treatments at our institution were retrospectively investigated. HR status in distant metastatic lesions and immunocompetent cells in peripheral blood were also studied. RESULTS: Progression-free survival (PFS) was significantly shorter in patients whose primary tumour was high grade (P = 0.016) or high neutrophil-to-lymphocyte ratio (NLR) at baseline (P = 0.017). Meanwhile, there were no differences in other factors, such as expression levels of hormone receptors. Patients whose metastatic lesions were of low tumour grade or high Ki67 labelling index had longer PFS, and such trends were more obvious than primary lesions. CONCLUSION: Our data indicate that tumour grade in primary lesion and NLR are potential predictive factors for CDKi-based treatments. Moreover, pathological assessment of metastatic lesions might also be useful.

Drug-induced aortitis of the subclavian artery caused by pegfilgrastim: a case report.

BACKGROUND: Pegfilgrastim is a modified version of granulocyte-colony stimulating factor (G-CSF), with a polyethylene glycol (PEG) that prolongs its half-life in peripheral blood. It is prophylactically administered during chemotherapy to prevent severe febrile neutropenia. G-CSF-related aortitis is a rare side effect but reports of this disease have been increasing in recent years, probably due to PEGylation. Herein, we report a case who developed pegfilgrastim-induced aortitis, localized to the right subclavian artery, during adjuvant chemotherapy. Her condition recovered without the use of steroids. CASE PRESENTATION: A 58-year-old woman was diagnosed with invasive ductal carcinoma of the left breast. She had a medical history of contralateral breast cancer and pyelonephritis. Following curative surgery for her left breast cancer, she received adjuvant chemotherapy. Two days after the first course of dose-dense paclitaxel, pegfilgrastim was used as planned. Eight days after the administration of pegfilgrastim, she developed a high fever of 38 °C and visited the emergency outpatient clinic 3 days after. Blood tests revealed an increased inflammatory response, and contrast-enhanced computed tomography (CT) revealed a wall thickening of the subclavian artery, suggesting aortitis caused by pegfilgrastim. She was hospitalized on day 15 when CRP increased to 21.5 mg/dL and the high fever continued. Blood and urine culture tests were negative throughout. Pegfilgrastim-induced aortitis was suspected and she was observed without the use of steroids. Seven days later, her fever abated. A contrast-enhanced CT scan on day 26 showed the subclavian artery wall thickening had disappeared. The patient continues to be afebrile and is currently on weekly paclitaxel without use of G-CSF. CONCLUSIONS: The onset of this disease is known to usually occur within 2 weeks after the first pegfilgrastim administration. Aortitis localized to the subclavian artery is relatively rare with the most frequent site being the aortic arch. Clinicians should be aware of the timing and location of onset of this disease.

Clinicopathological Examination of Metaplastic Spindle Cell Carcinoma of the Breast: Case Series.

BACKGROUND: Spindle cell carcinoma (SpCC) of the breast is a rare histological type, a subtype of metaplastic carcinoma characterized by atypical spindle cell and epithelial carcinoma. The proportions of the spindle cell and epithelial components vary among tumours. Due to its rarity, biological characteristics of this disease have been poorly studied. METHODS: In total, 10 patients with SpCC were surgically treated at our institution from January 2007 to December 2018. We retrospectively investigated these SpCC cases, focusing on the differences between spindle cell and epithelial components. Microsatellite status was also examined. RESULTS: Nine cases were triple-negative breast cancer (TNBC). The rates of high tumour grade were 70% in spindle cell components and 56% in epithelial components (P = .65), while the mean Ki67 labelling index were 63% and 58%, respectively (P = .71). Mean programmed death ligand 1 (PD-L1) expression in these components was 11% and 1%, respectively (P = .20). All 10 tumours were microsatellite stable. Patient outcomes of triple-negative SpCC did not differ from those of propensity-matched patients with conventional TNBC. CONCLUSIONS: Spindle cell components showed higher values in factors examined, although there was no statistically significant difference. Our data reveal that these 2 components of SpCC may be of different biological nature.

Clinicopathological features of breast cancer without mammographic findings suggesting malignancy.

BACKGROUND: Mammography (MG) is widely used for screening examinations. Dense breast reduces MG screening sensitivity, possibly delaying diagnosis. However, little is known about the characteristics of breast cancers without MG findings indicative of malignancy. Hence, we investigated breast cancer patients with tumors not detected by MG. PATIENTS AND METHODS: In total, 1758 Japanese patients with breast cancer, undergoing curative surgery between 2012 and 2018 without neo-adjuvant chemotherapy, were retrospectively investigated. Clinicopathological features were compared between patients without (MG-negative) and with (MG-positive) cancer-specific findings on MG. The current study included cases who came to our hospital after experiencing subjective symptoms, or whose tumors were detected by MG and/or US-screening. We reviewed results of both MG and US conducted at our institution. RESULTS: There were 201 MG-negative cases (11.4%). In patients with invasive disease, multivariate analysis revealed MG-negative patients to have higher breast density on MG (p < 0.001). Tumors of MG-negative patients were smaller (p < 0.001), showed less lymph node involvement (p = 0.011), and were of lower grade (p = 0.027). The majority of MG-negative tumors were found by ultrasound screening, being smaller than tumors in patients with subjective symptoms. In the MG-negative group, tumor characteristics such as tumor grade did not differ between those detected by screening versus subjective symptoms. CONCLUSION: Most tumors in MG-negative group patients were identified by US screening and the diseases were found at early stages with low malignancy. The usefulness of additional ultrasound with MG-screening might merit further investigations.

Microsatellite-Stable Radiation-Induced Angiosarcoma after Breast-Conserving Surgery: A Case Report.

Radiation-induced angiosarcoma (RIAS) after breast-conserving surgery is quite rare. Risk factors for RIAS have yet to be identified, due largely to the very low incidence of this disease. The etiologic mechanisms of RIAS are not understood, although some reports suggest that genome instability may contribute to RIAS development. An 81-year-old Japanese woman presented to our hospital after developing multiple dark purple nodules on her left breast. She had undergone breast-conserving surgery for left breast cancer and adjuvant radiotherapy for the conserved breast 9 years earlier. Punch biopsy of one of the dark purple nodules was performed and the pathological diagnosis was angiosarcoma. She underwent total mastectomy with an adequate margin, and skin collected from her left thigh was grafted onto the site. Pathologically, the surgical margin was negative. The tumor was negative for microsatellite instability (MSI). Considering her age, she has remained under careful observation with neither systemic treatment nor adjuvant radiation. The only standard therapy for RIAS currently available is complete resection. Hence, early detection is crucial to obtain an adequate margin, followed by careful observation after breast-conserving surgery. It is also essential to reveal the tumor etiology, and for that purpose, we believe that the MSI status may be beneficial for the further investigation of RIAS.

Predictive Factors for Non-sentinel Nodal Metastasis in Patients With Sentinel Lymph Node-positive Breast Cancer.

BACKGROUND: Axillary dissection is routinely conducted for all patients with sentinel node (SN)-positive breast cancer. Metastasis to non SNs is not often found after axillary dissection in patients with SN-positive breast cancer. Thus, we investigated clinicopathological features, including immune cells in peripheral blood, in order to identify factors related to metastasis to non-SNs. PATIENTS AND METHODS: We retrospectively investigated 184 patients with SN-positive disease, treated at our institution during the 2013 through 2018 period. All clinicopathological data were obtained before and during surgery. RESULTS: Metastasis to non SNs was observed in 64 cases (35%). The platelet-to-lymphocyte ratio (PLR) and the number of SN metastases were independent of metastasis to non SNs (p=0.023 and p=0.017, respectively). Patients with metastasis to non SNs had significantly lower PLR and more SN metastases. High lymphocyte number and low platelet number resulted in a low PLR. CONCLUSION: PLR might be a marker of metastasis to non SNs.