Impact of COVID-19 on breast cancer screening in the Brazilian Unified Health System (SUS)

Objectives: investigating the impact of the pandemic on breast cancer screening in the Unified Health System, in addition to comparing the data obtained from other countries. Method(s): a quantitative cross-sectional observational study was carried out, with references from the Cancer Information System - SISCAN on the number of mammograms performed from 2014 to 2022 by women in Brazil. Result(s): data regarding mammography in the high-risk population showed a drop of 38, 39% from 2019 to 2020. While in screening mammography, the decline was slightly more significant, at 39.18% in the same period. Regarding diagnostic mammography, the reduction was 33.15%, and in target population mammography, the peak was in 2019 with 2.721.075. On the other hand, the performance of mammography in patients already treated had a smaller decrease of 9.35%. Conclusion(s): there was a significant reduction in the number of mammograms performed in 2019 and 2020, which might lead to a late diagnosis of the disease and a worse prognosis.Copyright © 2023 Faculdade de Medicina de Ribeirao Preto - U.S.P.. All rights reserved.

The impact of COVID-19 on screening for colorectal, gastric, breast, and cervical cancer in Korea.

OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic has affected the utilization of healthcare services, including participation in cancer screening programs. We compared cancer screening participation rates for colorectal, gastric, breast, and cervical cancers among participants in the National Cancer Screening Program (NCSP) in 2019 and 2020 to address the potential distraction effect of COVID-19 on cancer screening. METHODS: Data from the NCSP for 4 cancer types (stomach, colorectal, breast, and cervical) in 2019 and 2020 were used to calculate cancer screening participation rates by calendar month, gender, age group, and geographical region. Monthly participation rates were analyzed per 1,000 eligible individuals. RESULTS: The screening participation rate decreased in 2020 compared to 2019 for all 4 cancers: colorectal (40.5 vs. 35.3%), gastric (61.9 vs. 54.6%), breast (63.8 vs. 55.8%), and cervical (57.8 vs. 52.2%) cancers. Following 2 major COVID-19 waves in March and December 2020, the participation rates in the 4 types of cancer screening dropped compared with those in 2019. The highest decline was observed in the elderly population aged 80 years and older (percentage change: -21% for colorectal cancer; -20% for gastric cancer; -26% for breast cancer; -20% for cervical cancer). CONCLUSIONS: After the 2 major COVID-19 waves, the screening participation rate for 4 types of cancer declined compared with 2019. Further studies are needed to identify the indirect effects of the COVID-19 pandemic on cancer patients, such as delayed diagnoses of cancer or excess cancer deaths.

Research Roundup

George Winter provides an overview of recently published articles that are of interest to practice nurses. Should you wish to look at any of the papers in more detail, a full reference is provided.

COVID-19 Pandemisinin Kanser Erken Teşhis Tarama ve Eğitim Merkezleri Hizmetlerinin Kullanımına Etkisi

Objective: This study was conducted to evaluate the impact of the COVID-19 pandemic on the use of Cancer Early Diagnosis, Screening, and Education Centers (KETEM) services. Materials and Methods: In this study, which was conducted as a descriptive retrospective cohort type, a total of 52.955 patient application records made to KETEM between January 1st and December 31st, 2017-2020 and January 1st-1 October 2021 were examined. The data obtained within the scope of the study were expressed as frequency and percentage. Results: In the study, it was determined that the numbers decreased as compared to previous three years (2017, 2018 and 2019) 70.4%, 59.1%, 68.8% for mammography screenings, 75.8%, 68.8%, 65.8% for HPV-Pap smear scans and 46.1%, 81.9%, and 72.2% for colorectal scans, respectively. Conclusion: It was detected that mammography, HPV-Pap, smear, and colorectal screenings offered within the scope of KETEM services decreased significantly in 2020 and 2021 which includes the pandemic process, compared to the previous years. It is estimated that cancers that cannot be detected in the early period due to the decrease in the number of applications will cause a significant increase in cancer mortality in the following years. Accordingly, it is recommended that the society, especially the individuals in the risk group, not delay their applications to cancer screening services, to take the necessary pandemic measures to inform them about making their applications without delay, and to improve their awareness about this issue. Amaç: Bu çalışma COVID-19 pandemisinin Kanser Erken Teşhis, Tarama ve Eğitim Merkezleri (KETEM) hizmetlerinin kullanımı üzerindeki etkisini değerlendirmek amacıyla yapılmıştır. Gereç ve Yöntem: Retrospektif kohort tipinde betimleyici olarak yürütülen bu araştırmada, 2017-2020 yıllarında 1 Ocak-31 Aralık tarihleri ile 1 Ocak-1 Ekim 2021 tarihleri arasında bir ilin Kanser Erken Teşhis, Tarama ve Eğitim Merkezleri'ne yapılan toplam 52.955 hasta başvuru kaydı incelenmiştir. Çalışma kapsamında elde edilen veriler frekans ve yüzde ile ifade edilmiştir. Bulgular: Çalışmada 2020 yılındaki mamografi tarama sayısının önceki üç yıla kıyasla (2017, 2018, 2019) sırasıyla %70.4, %59.1, %68.8 oranında;HPV-Pap smear tarama sayısının %75.8, %68.8, %65.8 oranında;kolorektal tarama sayısının ise sırasıyla %46.1, %81.9 ve %72.2 oranında düştüğü saptanmıştır. Sonuç: Bu araştırmada KETEM hizmetleri kapsamında sunulan mamografi, HPV-Pap smear ve kolorektal taramalarının pandemi sürecini kapsayan 2020 ve 2021 yıllarında önceki yıllara nazaran önemli düzeylerde azaldığı belirlenmiştir. Başvuru sayısındaki azalmaya bağlı olarak erken dönemde tespit edilemeyen kanserlerin ilerleyen yıllarda kanser mortalitesinde önemli bir artışa neden olacağı ön görülmektedir. Bu doğrultuda özellikle risk grubunda yer alan bireyler başta olmak üzere toplumun kanser tarama hizmetlerine başvurularını ertelememeleri, gerekli pandemi tedbirlerini alarak vakit kaybetmeden başvurularını gerçekleştirmeleri konusunda bilgilendirilmesi ve bu duruma yönelik farkındalıklarının geliştirilmesi önerilmektedir.

Comparison of Axillary Lymph Nodes on Breast MRI Before and After COVID-19 Booster Vaccination.

RATIONALE AND OBJECTIVES: Vaccine-related lymphadenopathy is a frequent finding following initial coronavirus disease 2019 (COVID-19) vaccination, but the frequency after COVID-19 booster vaccination is still unknown. In this study we compare axillary lymph node morphology on breast MRI before and after COVID-19 booster vaccination. MATERIALS AND METHODS: This retrospective, single-center, IRB-approved study included patients who underwent breast MRI between October 2021 and December 2021 after the COVID-19 booster vaccination. The axillary lymph node with the greatest cortical thickness ipsilateral to the side of vaccination was measured on MRI after booster vaccination and before initial COVID-19 vaccination. Comparisons were made between patients with and without increase in cortical thickness of ≥ 0.2 cm. Continuous covariates were compared using Wilcoxon rank-sum test and categorical covariates were compared using Fisher's exact test. Multiple comparison adjustment was made using the Benjamini-Hochberg procedure. RESULTS: All 128 patients were included. Twenty-four of 128 (19%) displayed an increase in lymph node cortical thickness of ≥ 0.2 cm. Patients who received the booster more recently were more likely to present cortical thickening, with a median of 9 days (IQR 5, 20) vs. 36 days (IQR 18, 59) (p < 0.001). Age (p = 0.5) and type of vaccine (p = 0.7) were not associated with thickening. No ipsilateral breast cancer or malignant lymphadenopathy were diagnosed on follow-up. CONCLUSION: Axillary lymphadenopathy on breast MRI following COVID-19 booster vaccination is a frequent finding, especially in the first 3 weeks after vaccination. Additional evaluation or follow-up may be omitted in patients with low concern for malignancy.

Analysis of operations of breast surgery during the COVID-19 epidemic

Background and Aims: Despite that the epidemic of novel coronavirus pneumonia (COVID-19) has been under effective control in China, the number of cases outside our country is continuously growing. So, the prevention and control situation is still grim. This study, taking the Department of Breast Surgery in the First Affiliated Hospital of Army Medical University as an example, was designed to analyze and summarize the operations of breast surgery in a comprehensive tertiary hospital during the epidemic, so as to provide effective reference and experiential practice for conducting safe and efficient breast surgery work during epidemic and post-epidemic periods. Methods: Thirty-seven patients with breast cancer admitted in the Department of Breast Thyroid Surgery of the First Affiliated Hospital of Army Medical University during the COVID-19 epidemic period of January 31, 2020 to February 20, 2020 were selected. The data of the patients including the clinical characteristics, protective measures and treatment effects were retrospectively analyzed. The main points of methods for patients' admission to hospital, preoperative preparation, intraoperative protection and postoperative recovery, as well as the self-protection and psychological counseling of the medical staff were summarized. The effects of specialized treatment and epidemic prevention and control were identified by follow up. The details for how to improve the cognition of potential risk for infectious diseases, and how to strengthen the prevention and control of epidemic disease and occupational protection during the post-epidemic period were analyzed from the aspects of surgical indications, aerosol management and clinic protection in combination with the diagnosis and treatment characteristics of breast surgery. Results: Thirty-seven patients received surgical treatment after the exclusion of the risk of COVID-19. The mean operative time was (152.23±46.19) min, the average intraoperative blood loss was (85.23±23.47) mL, and no intraoperative blood transfusion was required in any of the patients. Among the 37 breast cancer patients, 19 cases underwent 6 to 8 cycles of preoperative neoadjuvant therapy, of whom, complete pathological remission was obtained in 7 cases after surgery. Prolonged fever occurred in 2 patients after operation, which returned to normal after isolation, body temperature monitoring and symptomatic treatment, and COVID-19 was excluded by nucleic acid testing for SARS-CoV-2. After follow-up, no suspected COVID-19 symptoms such as fever, cough and fatigue were noted in any of the patients or their accompanying relatives, and also no suspected cases were observed among the relevant medical staff. Conclusion: During the epidemic period, on the premise of scientific prevention and control, and full avoidance of COVID-19 infection in both doctors and patients, aggressive treatment can be provided to breast cancer patients according to the local epidemic situation. The principles of "scientific decision-making, and humanistic service" should be continuously followed, and the various prevention and control guidelines and management norms issued by superiors should be strictly obeyed, and the necessary elements such as prehospital screening, preoperative preparation, intraoperative protection and postoperative recovery of the breast cancer patients should be completed according to the actual situation. Rigorous compliance with the protection measures against epidemic in all aspects of the pre-admission and perioperative period of the patients, and coordinated relations of the epidemic prevention and control with the specialized treatment, may maximally ensure the safe completion of breast surgery and protect the health of the patients and medical personnel. © 2020 by the Author(s).

Young Adult German Breast Cancer Patients Participating in a Three-Week Inpatient Mother-Child Rehab Program Have High Needs for Supportive Care.

A known cut-off problem hampers the interpretation of quality of life (QOL) scores. The purpose of this study was to apply a novel approach for the EORTC QLQ-C30 instrument to identify the proportion of breast cancer (BC) patients in need of supportive care. Changes in QOL during the COVID-19 pandemic were evaluated, as well as changes over time (after treatment termination and up to 4 years later). Data were obtained from a cohort study on young adult BC patients with minor children participating in a mother-child rehab program. Cross-sectional QOL data were collected from 2015 to 2021 (baseline). Follow-up data were available for up to 4 years after diagnosis for a subgroup. The baseline cohort included 853 women (mean age 35 years). More than 50% had a need for supportive care. In the subgroup with follow-up, this proportion remained at a high level up to several years after diagnosis. During the COVID-19 pandemic, changes regarding the proportion with this need were not as high as expected-with the exception of changes on the QLQ-C30 scale 'role functioning' (+15%). Even several years after diagnosis, every second BC patient with minor children had a need for supportive care, which is much higher than previously found. Healthcare staff should be aware of this potential need and should address this issue.

Health-Seeking Behavior Returning to Normalcy Overcoming COVID-19 Threat in Breast Cancer.

Purpose: The coronavirus disease 2019 (COVID-19) outbreak has significantly impacted the diagnosis and treatment of breast cancer. Our study investigated the change in diagnosis and treatment of breast cancer with the progress of COVID-19 pandemic. Materials and Methods: The study group comprised 6514 recently diagnosed breast cancer patients between January 1, 2019, and February 28, 2021. The patients were divided into two groups: pre-COVID-19 period (3182; January 2019 to December 2019) and COVID-19 pandemic period (3332; January 2020 to February 2021). Clinicopathological information related to the first treatment after breast cancer diagnosis was retrospectively collected and analyzed in the two groups. Results: Among the 6514 breast cancer patients, 3182 were in the pre-COVID-19 period and 3332 were in the COVID-19 pandemic period. According to our evaluation, the least breast cancer diagnosis (21.8%) was seen in the first quarter of 2020. The diagnosis increased gradually except for the fourth quarter in 2020. While early-stage breast cancer was diagnosed 1601(48.05%) during the COVID-19 pandemic (p=0.001), the number of surgical treatments increased 4.64% (p<0.000), and the treatment time was slightly shorter 2 days (p=0.001). The breast cancer subtype distribution was not statistically different between the pre-COVID-19 and COVID-19 period groups. Conclusion: In the early stages of the pandemic, the number of breast cancer cases temporarily decreased; however, they stabilized soon, and no significant differences could be identified in the diagnosis and treatment when compared to the period before the pandemic.

Assessing the Suitability of a Virtual 'Pink Warrior' for Older Breast Cancer Survivors during COVID-19: A Pilot Study.

The COVID-19 pandemic impacted the conduct of in-person physical activity (PA) interventions among older survivors of BC, who need such interventions to stay active and prevent functional decline. We tested the feasibility of virtually delivering an exergame-based PA intervention to older BC survivors. We enrolled 20 female BC survivors ≥55 years and randomly assigned them to two groups. The intervention group (Pink Warrior 2) received 12 weekly virtual exergame sessions with behavioral coaching, survivorship navigation support, and a Fitbit for self-monitoring. The control group received 12 weekly phone-based survivorship discussion sessions and wore a Mi Band 3. Feasibility was evaluated by rates of recruitment (≥0.92 participants/center/month), retention (≥80%), and group attendance (≥10 sessions), percentage of completed virtual assessments, and number of technology-related issues and adverse events. Intervention acceptability was measured by participants' ratings on a scale of 1 (strongly disagree) to 5 (strongly agree). The recruitment rate was 1.93. The retention and attendance rates were 90% and 88% (≥10 sessions), respectively. Ninety-six percent completed virtual assessments without an adverse event. Acceptability was high (≥4). The intervention met benchmarks for feasibility. Additional research is needed to further understand the impact of virtually delivered PA interventions on older BC survivors.

The impact of the COVID-19 pandemic on breast cancer screening and diagnosis in a Brazilian metropolitan area.

OBJECTIVES: To evaluate the performance of breast cancer screening and early diagnosis during the pandemic, compared to the pre-pandemic period.Setting: The public referral centre for screening in Campinas, São Paulo State, Brazil. METHODS: This is an audit study of performance screening and diagnostic indicators. Two periods were analysed: 2019, the pre-COVID period, and 2020, the COVID period. All women who underwent mammography in these periods were included. Indicators were compared between periods, and the US Breast Cancer Surveillance Consortium benchmarks were used as a reference. RESULTS: A comparison between the periods shows a reduction of 57.4% in screening and 4.4% in diagnosis using mammography. Cancer detection rate per 1000 screening mammograms dropped from 4.62 to 2.83 (p = 0.031), while it increased from 84.43 to 89.36 in diagnosis mammograms (p = 0.701), higher than the reference (34.4, p < 0.001). With regard to diagnosis, the proportion of minimal cancers was reduced (p = 0.005) and was lower than the reference (40.0%, p < 0.001), along with the proportion of node-negative invasive cancers (p < 0.001). The mean size of invasive tumours was similar in the two periods (32.50 mm and 33.40 mm, p = 0.808) but larger than the reference value (16.50 mm, p < 0.001). Recall rate was lower in the COVID period (22.55% vs. 27.37%, p = 0.015). CONCLUSION: The COVID pandemic caused an overall decrease in breast screening and detection of breast cancer cases, although the reduction in number of diagnosis mammograms performed was minimal. Tumour mean size was large in both periods, the pandemic highlighting a previous profile of detection at an advanced stage.

Long-term effects of the interruption of the Dutch breast cancer screening program due to COVID-19: A modelling study.

Due to COVID-19, the Dutch breast cancer screening program was interrupted for three months with uncertain long-term effects. The aim of this study was to estimate the long-term impact of this interruption on delay in detection, tumour size of screen-detected breast cancers, and interval cancer rate. After validation, the micro-simulation model SiMRiSc was used to calculate the effects of interruption of the breast cancer screening program for three months and for hypothetical interruptions of six and twelve months. A scenario without interruption was used as reference. Outcomes considered were tumour size of screen-detected breast cancers and interval cancer rate. Women of 55-59 and 60-64 years old at time of interruption were considered. Uncertainties were estimated using a sensitivity analysis. The three-month interruption had no clinically relevant long-term effect on the tumour size of screen-detected breast cancers. A 19% increase in interval cancer rate was found between last screening before and first screening after interruption compared to no interruption. Hypothetical interruptions of six and twelve months resulted in larger increases in interval cancer rate of 38% and 78% between last screening before and first screening after interruption, respectively, and an increase in middle-sized tumours in first screening after interruption of 26% and 47%, respectively. In conclusion, the interruption of the Dutch screening program is not expected to result in a long-term delay in detection or clinically relevant change in tumour size of screen-detected cancers, but only affects the interval cancer rate between last screening before and first screening after interruption.

Impact of the COVID-19 pandemic on breast cancer screening and early diagnosis / Impacto da pandemia da COVID-19 no rastreamento e no diagnóstico precoce de câncer de mama

RESUMO Objetivo analisar os impactos da pandemia da COVID-19 no rastreamento e de diagnóstico precoce para o câncer de mama. Métodos estudo ecológico com avaliação retrospectiva dos dados contidos no Departamento de Informática do Sistema Único de Saúde entre os anos de 2016 e 2020. A coleta foi norteada por um roteiro semiestruturado e o impacto da pandemia no rastreamento e no diagnóstico foi realizado por meio da aplicação de fórmula e da comparação com o ano de 2020. Resultados no Brasil, houve uma queda significativa na quantidade de mamografias realizadas durante a pandemia da COVID-19, com diferença de 361.855 de 2016 para 2020. A idade de maior investigação diagnóstica foi entre 50 e 59 anos e a faixa etária com queda expressiva na realização da mamografia foi a de mulheres de 40 anos. Conclusão a pandemia da COVID-19 impactou, negativamente, o rastreamento e o diagnóstico precoce para o câncer de mama devido à redução dos atendimentos. Contribuições para a prática: reforçar a importância de investimentos no campo de políticas públicas diante de um cenário pandêmico para que os protocolos de rastreamento e de tratamento já estejam bem direcionados a fim de garantir uma melhor assistência aos pacientes oncológicos.

ABSTRACT Objective to analyze the impacts of the COVID-19 pandemic on breast cancer screening and early diagnosis. Methods an ecological retrospective study of data from the Department of Informatics of the Unified Health System collected between 2016 and 2020 was carried out. The data collection was guided by a semi-structured script, and the impact of the pandemic on breast cancer screen and diagnosis was established by using a formula and comparing the period of interest to 2020. Results in Brazil, there was a significant drop in mammograms performed during the COVID-19 pandemic, with a decrease of 361,855 exams from 2016 to 2020. Most diagnostic investigations were conducted with patients between 50 and 59 years, and there was a significant drop in mammograms in women aged under 40 years. Conclusion the COVID-19 pandemic has negatively impacted screening and early diagnosis of breast cancer due to reduced availability. Contributions to practice: the study reinforces the importance of investing in public policies to face the pandemic scenario so that screening and treatment protocols be well targeted to guarantee better care for cancer patients.

Journey to hypofractionation in radiotherapy for breast cancer: critical reviews for recent updates.

Historical conventional fractionated radiation therapy (RT) for breast cancer consisted of 1.8-2.0 Gy per fraction with a total dose of 45-60 Gy over 5-7 weeks. Based on radiobiological characteristics, a low α/ß is suspected of breast cancer resulting in sensitivity to higher dose per fraction (2.5-3.0 Gy). Over the past 10 years, multiple clinical trials support the application of shorter treatment regimen with hypofractionated RT (HypoRT). Recently, ultra-HypoRT with 5 fractions showed favorable outcomes. Although the safety and efficacy of HypoRT has been supported by high-quality randomized trials, there are still some worries and doubts around HypoRT from radiation oncologists. However, the radiation oncology community have now reached an important timepoint for adopting HypoRT during the COVID-19 pandemic. The aim of this review is to provide an overview of HypoRT in breast cancer based on prospective randomized trials and discuss the special consideration regarding HypoRT.

The trend and direct costs of screening and chemotherapy treatment of breast cancer in the new coronavirus pandemic: total and interrupted time series study.

BACKGROUND: The COVID-19 pandemic has overloaded the healthcare systems of many countries and reduced the population's access to treatment and prevention of other diseases. This study aims to assess whether the COVID-19 pandemic has negatively interfered with the trend and the direct costs of screening and chemotherapy treatment of breast cancer in a public and universal healthcare system. METHOD: This was an ecological time series study using an open database of a public and universal health system from 2017 to 2021. RESULTS: In 2020, there was a 41% reduction in the coverage rate of breast cancer screening in women aged 50 to 69 years (about 1 million mammograms missed). The total direct cost of breast cancer screening reduced proportionally to the number of tests (BRL 67 million). On the other hand, the cost of chemotherapy treatment was higher in 2020, both in advanced (BRL 465 million) and localized (BRL 113 million) diseases. In the time series, mammograms' trend and direct costs changed from stationary to decreasing after the COVID-19 pandemic. The trend of direct costs with chemotherapy treatment for the advanced disease has been increasing and has not changed after the COVID-19 pandemic. On the other hand, in the case of localized disease, there was a trend toward reducing direct costs after the pandemic. CONCLUSION: After COVID-19, there was a downward trend in breast cancer screening and its direct costs, an upward trend in chemotherapy costs for advanced disease, and a downward trend in chemotherapy costs for localized disease.

Bioinformatics analysis of changes in genes associated with tumor-associated macrophages before and after neoadjuvant chemotherapy for breast cancer

Background and Aims: Breast cancer is the most prevalent malignancy in women worldwide, and chemotherapy is one of the most important treatment modalities for breast cancer. Recent studies have shown that chemotherapy may exert anti-tumor effects by enhancing anti-tumor immunity in the tumor microenvironment. Therefore, this study was conducted to identify the changes in tumor-associated macrophages (TAMs) and relevant genes before and after neoadjuvant chemotherapy (NAC) in breast cancer patients by bioinformatics analysis and to evaluate the effect of NAC on immune functions in breast cancer patients. Methods: Information searching was performed by entering "Breast Cancer", "TAMs", "Chemotherapy" and selecting the human breast cancer tissue in the GEO database, and the GSE134600 dataset was selected for analysis. Differentially expressed genes (DEGs) in tissue samples from breast cancer patients before and after NAC were screened by R package (limma function). GO function enrichment and KEGG pathway analysis were performed for all DRGs. The protein interaction network of DEGs was visualized by Cytoscape software, and hub genes were screened and 10 hub genes were analyzed for mutations by cBioPortal. Immune cell distribution and correlation in GSE134600 data were evaluated using the R package“CIBERSORT”. Results: A total of 751 DEGs (409 up-regulated and 342 down-regulated genes) were identified before and after NAC for breast cancer. The biology of DEGs was analyzed by GO enrichment for biological process（BP）, cellular component （CC）, and molecular function（MF）. In BP function, they were mainly enriched in type I interferon(IFN-I) signaling pathway/viral response and defense and viral life cycle;in CC function, they were mainly enriched in extrinsic components of cell membrane and cytoplasmic side of cell membrane;in MF function, they were mainly enriched in cytokine receptor binding, double-stranded RNA binding and lipopeptide binding. In the analysis of KEGG pathway enrichment, DEGs were mainly enriched in influenza A (H1N1), measles, hepatitis C, coronavirus disease COVID-19, NF-κB signaling pathway, EBV virus infection, NOD-like receptor signaling pathway, and amoeba disease signaling pathway. The top 10 hub genes with the highest degree of interaction with TAMs before and after NAC for breast cancer were screened by CytoHubba plug-in: IFIT1, ISG15, MX1, MX2, IRF7, RSAD2, IFIT3, IFI35, IFI6, and IFITM1. Multi-omics analysis revealed that IFIT1, MX1 and MX2 were mainly deletion mutations, IFIT1 mainly had deep gene deletion, while MX1 and MX2 were mainly associated with gene amplifications. The content of M0 macrophages, CD8+T cells and M2 macrophages in breast cancer tissues decreased after NAC, and M0 macrophages were positively correlated with memory B cells (r=0.64) and negatively correlated with unactivated CD4+ memory T cells (r=-0.66). Conclusion: The identified DEGs associated with TAMs in breast cancer patients before and after NAC are closely related to interferon signaling pathway, suggesting that interferon signaling pathway may play an important role by altering TAMs in NAC. Meanwhile, M0 macrophages are significantly altered before and after NAC, indicating that chemotherapy may regulate the immune response to tumor by changing the distribution of M0 macrophages and immune function. © 2022 Central South University. All right reserved.