Longitudinal molecular profiling elucidates immunometabolism dynamics in breast cancer.

Although metabolic reprogramming within tumor cells and tumor microenvironment (TME) is well described in breast cancer, little is known about how the interplay of immune state and cancer metabolism evolves during treatment. Here, we characterize the immunometabolic profiles of tumor tissue samples longitudinally collected from individuals with breast cancer before, during and after neoadjuvant chemotherapy (NAC) using proteomics, genomics and histopathology. We show that the pre-, on-treatment and dynamic changes of the immune state, tumor metabolic proteins and tumor cell gene expression profiling-based metabolic phenotype are associated with treatment response. Single-cell/nucleus RNA sequencing revealed distinct tumor and immune cell states in metabolism between cold and hot tumors. Potential drivers of NAC based on above analyses were validated in vitro. In summary, the study shows that the interaction of tumor-intrinsic metabolic states and TME is associated with treatment outcome, supporting the concept of targeting tumor metabolism for immunoregulation.

Human Epidermal Growth Factor Receptor 2 (HER2) PET Imaging of HER2-Low Breast Cancer with [68Ga]Ga-ABY-025: Results from a Pilot Study.

Patients with HER2-low metastatic breast cancer (mBC), defined as an immunohistochemistry (IHC) score of 1+ or 2+ without HER2 gene amplification, may benefit from HER2 antibody-drug conjugates. Identifying suitable candidates is a clinical challenge because of spatial and temporal heterogeneity in HER2 expression and discrepancies in pathologic reporting. We aimed to investigate the feasibility and safety of HER2-specific PET imaging with [68Ga]Ga-ABY-025 for visualization of HER2-low mBC. Methods: A prospective pilot study was done with 10 patients who had HER2-low mBC, as part of a phase 2 basket imaging study with [68Ga]Ga-ABY-025 in HER2-expressing solid tumors. Patients were recruited at the Breast Clinic at the Karolinska University Hospital, Stockholm, Sweden. PET/CT images were acquired 3 h after injection of 200 MBq of [68Ga]Ga-ABY-025. The SUVmax was used to quantify tracer uptake. Ultrasound-guided tumor biopsies were guided by results from the HER2 PET. The main outcome-the safety and feasibility of HER2 PET in patients with HER2-low mBC, measured the occurrence of possible procedure-related adverse events. Results: Ten patients with HER2-low mBC underwent [68Ga]Ga-ABY-025 PET/CT with paired tumor biopsies. No adverse events occurred. In all patients, [68Ga]Ga-ABY-025-avid lesions with substantial intra- and interindividual heterogeneity in tracer uptake were noted. In 8 of 10 patients with ABY-025-avid lesions, the HER2-low status of the corresponding lesions was confirmed by IHC or in situ hybridization. Two patients had an IHC score of 0 in the tumor biopsies:1 in a cutaneous lesion with a low SUVmax and 1 in a liver metastasis with a high SUVmax but a "cold" core. Conclusion: The visualization of HER2-low mBC with [68Ga]Ga-ABY-025 PET/CT was feasible and safe. Areas of tracer uptake showed varying levels of HER2 expression on IHC. The observed intra- and interindividual heterogeneity in [68Ga]Ga-ABY-025 uptake suggested that HER2 PET might be used as a tool for the noninvasive assessment of disease heterogeneity and has the potential to identify patients in whom HER2-targeted drugs can have a clinical benefit.

Gonadotropin Releasing Hormone agonist (GnRHa) during chemotherapy and post-cancer childbirths - a Nationwide population-based cohort study of 24,922 women diagnosed with cancer in Sweden.

Background: Worldwide, an increasing number of women with cancer are receiving Gonadotropin Releasing Hormone agonist (GnRHa) co-treatment during chemotherapy aiming at ovarian protection. There is divergence among guidelines, and some have recommended GnRHa co-treatment for women with breast cancer, however, the effect of GnRHa on future fertility is uncertain. Methods: In this population-based cohort study we included all women diagnosed with cancer at ages 15-45 between July 2005 and March 2017 in Sweden, identified in the Swedish Cancer Register. Exposure to GnRHa co-treatment was captured using the Prescribed Drug Register. Post-cancer childbirth, extracted from the Medical Birth Register, was the main outcome. Secondary outcomes included childbirths achieved through natural conception (NC), infertility diagnosis and cancer mortality. For each outcome, adjusted hazard ratios (aHR) and 95% confidence intervals (CI) were estimated using delayed-entry Cox models, stratified by age and cancer site. Findings: Among 24,922 women diagnosed with cancer, 1.5% had GnRHa co-treatment. Breast cancer diagnoses were found in 80.2% of GnRHa exposed women and the GnRHa exposure was not associated with higher rates of childbirth (aHR 1.23, 95% CI 0.80-1.89), or NC childbirth (aHR 1.02, 95% CI 0.62-1.67), whereas the rate of infertility was significantly higher (aHR 2.42, 95% CI 1.44-4.08). In women with lymphoma and other cancers, GnRHa exposure was not associated with higher rates of childbirth, NC childbirth or infertility. GnRHa exposure was not associated with higher cancer mortality for any cancer type. Interpretation: We did not find evidence of improved or maintained fertility, estimated as childbirth rates post-cancer, in women who received GnRHa during cancer treatment. Funding: This study was financed by research grants from The Swedish Cancer Society (CAN 2017/704; 190249Pj, 200170F), The Swedish Research Council (Dnr 2019-00446), the Nordic Cancer Union NCU (Grant 2017), The Swedish Childhood Cancer Fund (KP2016-0031), Radiumhemmets Forskningsfonder (Dnr: 201313), Stockholm County Council (FoUI-953912) and Karolinska Institutet (Dnr 2020-01963).

The role of serum thymidine kinase 1 activity in neoadjuvant-treated HER2-positive breast cancer: biomarker analysis from the Swedish phase II randomized PREDIX HER2 trial.

BACKGROUND: Thymidine kinase 1 (TK1) plays a pivotal role in DNA synthesis and cellular proliferation. TK1 has been studied as a prognostic marker and as an early indicator of treatment response in human epidermal growth factor 2 (HER2)-negative early and metastatic breast cancer (BC). However, the prognostic and predictive value of serial TK1 activity in HER2-positive BC remains unknown. METHODS: In the PREDIX HER2 trial, 197 HER2-positive BC patients were randomized to neoadjuvant trastuzumab, pertuzumab, and docetaxel (DPH) or trastuzumab emtansine (T-DM1), followed by surgery and adjuvant epirubicin and cyclophosphamide. Serum samples were prospectively collected from all participants at multiple timepoints: at baseline, after cycle 1, 2, 4, and 6, at end of adjuvant therapy, annually for a total period of 5 years and/or at the time of recurrence. The associations of sTK1 activity with baseline characteristics, pathologic complete response (pCR), event-free survival (EFS), and disease-free survival (DFS) were evaluated. RESULTS: No association was detected between baseline sTK1 levels and all the baseline clinicopathologic characteristics. An increase of TK1 activity from baseline to cycle 2 was seen in all cases. sTK1 level at baseline, after 2 and 4 cycles was not associated with pCR status. After a median follow-up of 58 months, 23 patients had EFS events. There was no significant effect between baseline or cycle 2 sTK1 activity and time to event. A non-significant trend was noted among patents with residual disease (non-pCR) and high sTK1 activity at the end of treatment visit, indicating a potentially worse long-term prognosis. CONCLUSION: sTK1 activity increased following neoadjuvant therapy for HER2-positive BC but was not associated with patient outcomes or treatment benefit. However, the post-surgery prognostic value in patients that have not attained pCR warrants further investigation. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02568839. Registered on 6 October 2015.

Breast cancer during pregnancy-The oncologist's point of view.

Breast cancer is the most common malignancy diagnosed during or directly after pregnancy. Differences in pathogenesis and prognosis identify two distinct patient groups, those with breast cancer during pregnancy and those with postpartum breast cancer which, for reasons not completely understood, is associated with worse outcomes. Compared with breast cancer in the non-pregnant patient, several limitations in terms of both local and systemic therapy are applied to limit fetal harm. Treatment is nevertheless delivered with curative intent, therefore avoiding harmful delays in therapy initiation, unnecessary therapy de-escalation or chemotherapy dose modifications is strongly recommended. In this short commentary, we briefly review current evidence and treatment guidelines and provide recommendations for optimal oncologic management of pregnancy-related breast cancer.

ProFertil study protocol for the investigation of gonadotropin-releasing hormone agonists (GnRHa) during chemotherapy aiming at fertility protection of young women and teenagers with cancer in Sweden-a phase III randomised double-blinded placebo-controlled study.

BACKGROUND: Gonadotropin-releasing hormone agonists (GnRHa) cotreatment used to transiently suppress ovarian function during chemotherapy to prevent ovarian damage and preserve female fertility is used globally but efficacy is debated. Most clinical studies investigating a beneficial effect of GnRHa cotreatment on ovarian function have been small, retrospective and uncontrolled. Unblinded randomised studies on women with breast cancer have suggested a beneficial effect, but results are mixed with lack of evidence of improvement in markers of ovarian reserve. Unblinded randomised studies of women with lymphoma have not shown any benefit regarding fertility markers after long-term follow-up and no placebo-controlled study has been conducted so far. The aim of this study is to investigate if administration of GnRHa during cancer treatment can preserve fertility in young female cancer patients in a double-blind, placebo-controlled clinical trial. METHODS AND ANALYSIS: A prospective, randomised, double-blinded, placebo-controlled, phase III study including 300 subjects with breast cancer. In addition, 200 subjects with lymphoma, acute leukemias and sarcomas will be recruited. Women aged 14-42 will be randomised 1:1 to treatment with GnRHa (triptorelin) or placebo for the duration of their gonadotoxic chemotherapy. Follow-up until 5 years from end of treatment (EoT). The primary endpoint will be change in anti-Müllerian hormone (AMH) recovery at follow-up 12 months after EoT, relative to AMH levels at EoT, comparing the GnRHa group and the placebo group in women with breast cancer. ETHICS AND DISSEMINATION: This study is designed in accordance with the principles of Good Clinical Practice (ICH-GCP E6 (R2)), local regulations (ie, European Directive 2001/20/EC) and the ethical principles of the Declaration of Helsinki. Within 6 months of study completion, the results will be analysed and the study results shall be reported in the EudraCT database. STUDY REGISTRATION: The National Institutional review board in Sweden dnr:2021-03379, approval date 12 October 2021 (approved amendments 12 June 2022, dnr:2022-02924-02 and 13 December 2022, dnr:2022-05565-02). The Swedish Medical Product Agency 19 January 2022, Dnr:5.1-2021-98927 (approved amendment 4 February 2022). Manufacturing authorisation for authorised medicinal products approved 6 December 2021, Dnr:6.2.1-2020-079580. Stockholm Medical Biobank approved 22 June 2022, RBC dnr:202 253. TRIAL REGISTRATION NUMBER: NCT05328258; EudraCT number:2020-004780-71.

VEGF-C-expressing TAMs rewire the metastatic fate of breast cancer cells.

The expression of pro-lymphangiogenic VEGF-C in primary tumors is associated with sentinel lymph node metastasis in most solid cancer types. However, the impact of VEGF-C on distant organ metastasis remains unclear. Perivascular tumor-associated macrophages (TAMs) play a crucial role in guiding hematogenous spread of cancer cells by establishing metastatic pathways within the tumor microenvironment. This process supports breast cancer cell intravasation and metastatic dissemination. We show here that VEGF-C-expressing TAMs reduce the dissemination of mammary cancer cells to the lungs while concurrently increasing lymph node metastasis. These TAMs express podoplanin and interact with normalized tumor blood vessels expressing VEGFR3. Moreover, clinical data suggest inverse association between VEGF-C-expressing TAMs and breast cancer malignancy. Thus, our study elucidates the paradoxical role of VEGF-C-expressing TAMs in redirecting cancer cells to preferentially disseminate to lymph nodes rather than to lungs, partially achieved by normalizing tumor blood vessels and promoting lymphangiogenesis.

Risk-adjusted benchmarking of long-term overall survival in patients with HER2-positive early-stage Breast cancer: A Swedish retrospective cohort study.

AIM: The main objective of the current study was to explore the value of risk-adjustment when comparing (i.e. benchmarking) long-term overall survival (OS) in breast cancer (BC) between Swedish regions. We performed risk-adjusted benchmarking of 5- and 10-year OS after HER2-positive early BC diagnosis between Sweden's two largest healthcare regions, constituting approximately a third of the total population in Sweden. METHODS: All patients diagnosed with HER2-positive early-stage BC between 01-01-2009 and 31-12-2016 in healthcare regions Stockholm-Gotland and Skane were included in the study. Cox proportional hazards model was used for risk-adjustment. Unadjusted (i.e. crude) and adjusted 5- and 10-year OS was benchmarked between the two regions. RESULTS: The crude 5-year OS was 90.3% in the Stockholm-Gotland region and 87.8% in the Skane region. The crude 10-year OS was 81.7% in the Stockholm-Gotland region and 77.3% in the Skane region. However, when adjusted for age, menopausal status and tumour biology, there was no significant OS disparity between the regions, neither at the 5-year nor 10-year follow-up. CONCLUSION: This study showed that risk-adjustment is relevant when benchmarking OS in BC, even when comparing regions from the same country that share the same national treatment guidelines. This is, to our knowledge, the first published risk-adjusted benchmarking of OS in HER2-positive BC.

Long-term and real-life incidence of cancer therapy-related cardiovascular toxicity in patients with breast cancer: a Swedish cohort study.

Background: The administration of anticancer drugs in females with comorbidity increases the risk for cancer therapy-related cardiovascular toxicity (CTR-CVT), which in turn contributes to cardiovascular disease (CVD). Furthermore, a pathophysiological connection between cancer and cardiovascular disease may exist. Objective: To assess the long-term risks and predictors of CTR-CVT, including clinical hypertension (HT), coronary artery disease (CAD), heart failure (HF), atrial fibrillation (AF), as well as all-cause mortality in women diagnosed with early breast cancer (BC) and eligible for adjuvant chemotherapy in Sweden. Methods: Data were extracted from Swedish registers and medical records on 433 women, 18-60 years of age, diagnosed 1998-2002 with lymph node-positive BC, and considered for adjuvant chemotherapy. CTR-CVT was defined as HT, CAD, HF, or AF after the diagnosis of BC. Follow-up was from the date of BC diagnosis until November 30, 2021, or death. Prevalence of CTR-CVT and all-cause mortality were calculated. Hazard ratios (HR) were determined for factors associated with CTR-CVT. Results: The median age was 50 (interquartile range (IQR) 32) years. 910 CTR-CVT events were diagnosed in 311 women with a median of 19.3 (IQR 15,3) years follow-up. The proportions of CTR-CVT events were: HT 281 (64%); CAD 198 (46%); HF 206 (47%); and AF 225 (51%). The cumulative incidence of CTR-CVT was 71.8%, and 50% of all 433 patients developed CTR-CVT within 11.7 years of BC diagnosis (standard deviation (SD) 0.57, 95% confidence interval (CI) 10.6-12.9). Age was a risk factor for CTR-CVT. Anthracycline increased the risk for HF (p=0,001; HR 2,0; 95%CI 1,4-2,8), CAD (p= 0,002; HR 1,7; 95% CI 1,2-2,4), and AF (p=0,013; HR 1,5; 95% CI 1,0-2,0). At the end of the 24-year study period, 227 of the 433 women were alive, and the total cumulative mortality was 47,6%. Conclusion: The prevalence of CTR-CVT and all-cause mortality is high after BC diagnosis and treatment, particularly in older patients and those receiving anthracyclines. These findings and the onset of CTR-CVT support cardio-oncology guidelines recommending initial risk stratification and cardiovascular monitoring during treatment, followed by long-term annual screening for cardiovascular risk factors and CTR-CVT among BC survivors.

Current status of contemporary diagnostic radiotracers in the management of breast cancer: first steps toward theranostic applications.

BACKGROUND: Expanding therapeutic possibilities have improved disease-related prospects for breast cancer patients. Pathological analysis on a tumor biopsy is the current reference standard biomarker used to select for treatment with targeted anticancer drugs. This method has, however, several limitations, related to intra- and intertumoral as well as spatial heterogeneity in receptor expression as well as the need to perform invasive procedures that are not always technically feasible. MAIN BODY: In this narrative review, we focus on the current role of molecular imaging with contemporary radiotracers for positron emission tomography (PET) in breast cancer. We provide an overview of diagnostic radiotracers that represent treatment targets, such as programmed death ligand 1, human epidermal growth factor receptor 2, polyadenosine diphosphate-ribose polymerase and estrogen receptor, and discuss developments in therapeutic radionuclides for breast cancer management. CONCLUSION: Imaging of treatment targets with PET tracers may provide a more reliable precision medicine tool to find the right treatment for the right patient at the right time. In addition to visualization of the target of treatment, theranostic trials with alpha- or beta-emitting isotopes provide a future treatment option for patients with metastatic breast cancer.

Adherence to endocrine therapy in early breast cancer in relation to Cytochrome P450 2D6 genotype: a comparison between pharmacy dispensation data and medical records.

PURPOSE: Suboptimal adherence to adjuvant endocrine treatment (AET) is an important clinical concern. A correlation between CYP2D6 activity and tamoxifen discontinuation has been described. The main aim of this study was to investigate the consistency between pharmacy dispensation data and medical records on adherence to AET. METHODS: Adherence was calculated for patients with at least 4.5 years of follow up and was defined as Medical Possession Rate ≥ 80%. Subgroup analyses were performed based on menopausal status, recurrence risk and CYP2D6 activity. RESULTS: In 86% of the 1235 included patients the consistency between the two sources of information was within 80-125%. Poor consistency, < 80%, was most frequent in the premenopausal/ high-risk group and CYP2D6 Poor Metabolizers (PMs). Among 899 patients with at least 4.5 years follow up, 72% were adherent to tamoxifen based on pharmacy dispensation data, compared with 77% as reported by medical records. When including patients who switched to aromatase inhibitors after tamoxifen, adherence increased to 82% and 88%, respectively. Adherence did not differ by menopausal status or risk for recurrence. CYP2D6 PMs had poorer adherence (54%) to tamoxifen compared to patients with the highest CYP2D6 activity (83%). CONCLUSIONS: There was a good consistency between medical records and pharmacy dispensing data on the use of AET. Adherence to AET was adequate, especially when including switch to aromatase inhibitors. Surprisingly, CYP2D6 PMs had low adherence to tamoxifen, despite a likely reduced risk of side effects according to previous data.

Breast cancer patient-derived whole-tumor cell culture model for efficient drug profiling and treatment response prediction.

Breast cancer (BC) is a complex disease comprising multiple distinct subtypes with different genetic features and pathological characteristics. Although a large number of antineoplastic compounds have been approved for clinical use, patient-to-patient variability in drug response is frequently observed, highlighting the need for efficient treatment prediction for individualized therapy. Several patient-derived models have been established lately for the prediction of drug response. However, each of these models has its limitations that impede their clinical application. Here, we report that the whole-tumor cell culture (WTC) ex vivo model could be stably established from all breast tumors with a high success rate (98 out of 116), and it could reassemble the parental tumors with the endogenous microenvironment. We observed strong clinical associations and predictive values from the investigation of a broad range of BC therapies with WTCs derived from a patient cohort. The accuracy was further supported by the correlation between WTC-based test results and patients' clinical responses in a separate validation study, where the neoadjuvant treatment regimens of 15 BC patients were mimicked. Collectively, the WTC model allows us to accomplish personalized drug testing within 10 d, even for small-sized tumors, highlighting its potential for individualized BC therapy. Furthermore, coupled with genomic and transcriptomic analyses, WTC-based testing can also help to stratify specific patient groups for assignment into appropriate clinical trials, as well as validate potential biomarkers during drug development.

Survival Outcomes, Digital TILs, and On-treatment PET/CT During Neoadjuvant Therapy for HER2-positive Breast Cancer: Results from the Randomized PREDIX HER2 Trial.

PURPOSE: PREDIX HER2 is a randomized Phase II trial that compared neoadjuvant docetaxel, trastuzumab, and pertuzumab (THP) with trastuzumab emtansine (T-DM1) for HER2-positive breast cancer. Rates of pathologic complete response (pCR) did not differ between the two groups. Here, we present the survival outcomes from PREDIX HER2 and investigate metabolic response and tumor-infiltrating lymphocytes (TIL) as prognostic factors. PATIENTS AND METHODS: In total, 202 patients with HER2-positive breast cancer were enrolled and 197 patients received six cycles of either THP or T-DM1. Secondary endpoints included event-free survival (EFS), recurrence-free survival (RFS), and overall survival (OS). Assessment with PET/CT was performed at baseline, after two and six treatment cycles. TILs were assessed manually at baseline biopsies, while image-based evaluation of TILs [digital TILs (DTIL)] was performed in digitized full-face sections. RESULTS: After a median follow-up of 5.21 years, there was no difference between the two treatment groups in terms of EFS [HR = 1.26; 95% confidence interval (CI), 0.54-2.91], RFS (HR = 0.69; 95% CI, 0.24-1.93), or OS (HR = 0.52; 95% CI, 0.09-2.82). Higher SUVmax at cycle 2 (C2) predicted lower pCR (ORadj = 0.65; 95% CI, 0.48-0.87; P = 0.005) and worse EFS (HRadj = 1.27; 95% CI, 1.12-1.41; P < 0.001). Baseline TILs and DTILs provided additional prognostic information to clinical parameters and C2 SUVmax. CONCLUSIONS: Long-term outcomes following neoadjuvant T-DM1 were similar to neoadjuvant THP. SUVmax after two cycles of neoadjuvant therapy for HER2-positive breast cancer may be an independent predictor of both short- and long-term outcomes. Combined assessment with TILs may facilitate early selection of poor responders for alternative treatment strategies.

Expression patterns and prognostic implications of tumor-infiltrating lymphocytes dynamics in early breast cancer patients receiving neoadjuvant therapy: A systematic review and meta-analysis.

Purpose: High levels of tumor-infiltrating lymphocytes (TILs) are associated with better outcomes in early breast cancer and higher pathological response rates to neoadjuvant chemotherapy especially in the triple-negative (TNBC) and HER2+ subtypes. However, the dynamic changes in TILs levels after neoadjuvant treatment (NAT) are less studied. This systematic review and meta-analysis aimed to investigate the patterns and role of TILs dynamics change in early breast cancer patients receiving NAT. Methods: Medline, Embase, Web of Science Core Collection and PubMed Central databases were searched for eligible studies. Data were extracted independently by two researchers and discordances were resolved by a third. Pooled TILs rates pre- & post-treatment (overall and per subtype), pooled rates of ΔTILs and direction of change after NAT as well as correlation of ΔTILs with survival outcomes were generated in the outcome analysis. Results: Of 2116 identified entries, 34 studies fulfilled the criteria and provided adequate data for the outcomes of interest. A decreased level of TILs was observed after NAT in paired samples across all subtypes. The effect of NAT on TILs was most prominent in TNBC subtype with a substantial change, either increase or decrease, in 79.3% (95% CI 61.7-92.6%) of the patients as well as in HER2+ disease (14.4% increased vs 46.2% decreased). An increase in ΔTILs in TNBC was associated with better disease-free/relapse-free survival in pooled analysis (univariate HR = 0.59, 95% CI: 0.37-0.95, p = 0.03). Conclusion: This meta-analysis illustrates the TILs dynamics during NAT for breast cancer and indicates prognostic implications of ΔTILs in TNBC. The potential clinical utility of the longitudinal assessment of TILs during neoadjuvant therapy warrants further validation.

[HER2-low breast cancer - A new entity that could expand possibilities of getting treatment]. / HER2-låg bröstcancer ny entitet ­ ökar behandlingsmöjligheterna.

Breast cancer is the most common form of cancer among women in Sweden. Several decades ago it was recognized that the Human epidermal growth factor receptor 2 (HER2) is involved in a critical growth system for breast cancer cells. Overexpression of HER2 (immunohistochemistry [IHC] 2+/3+, in situ hybridization [ISH] positive) is present in 15 percent of all breast cancers. HER2-low breast cancer has been discovered as a separate entity; the most commonly used definition so far is IHC 1+/2+ and ISH negative, but general consensus is still lacking. Clinical studies with the HER2 antibody drug conjugate trastuzumab deruxtecan (Enhertu) have shown impressive antitumor activity among women with advanced HER2-low breast cancer and this is expected to become part of routine treatment in the near future. Research is needed to establish refined ways to define HER2-low breast cancer, and a possible role lies in new imaging methods such as HER2 positron emission tomography (PET) with a [68Ga]Ga-ABY-025 tracer.

Relapse Rates and Disease-Specific Mortality Following Procedures for Fertility Preservation at Time of Breast Cancer Diagnosis.

Importance: Breast cancer (BC) is the most common indication for fertility preservation (FP) in women of reproductive age. Procedures for FP often include hormonal stimulation, but current data are scarce regarding whether using hormonal stimulation for FP is associated with any deterioration in BC prognosis. Objective: To investigate the risk of disease-specific mortality and relapse in women who underwent FP with or without hormonal stimulation compared with women who did not at time of BC diagnosis. Design, Setting, and Participants: This Swedish nationwide prospective cohort study was conducted to assess the safety of hormonal and nonhormonal FP procedures indicated by BC in Sweden from January 1, 1994, through June 30, 2017. Women were identified from any of the regional FP programs located at Swedish university hospitals. A total of 425 women were found to have undergone FP, and 850 population comparators who had not undergone FP were sampled from regional BC registers and matched on age, calendar period of diagnosis, and region. Relapse-free survival was assessed in a subcohort of 241 women who underwent FP and 482 women who had not, with complete data. Nationwide demographic and health care registers provided data on outcome, disease- and treatment-related variables, and socioeconomic characteristics. Data analyses were performed between November 2021 and March 2022 and completed in June 2022. Main Outcomes and Measures: Relapse and disease-specific mortality after a diagnosis of BC. Results: The final study population included 1275 women (mean [SD] age, 32.9 [3.8] years) at the time of BC diagnosis. After stratification by the matching variables age, calendar period, and region, and adjustment for country of birth, education, parity at diagnosis, tumor size, number of lymph node metastases, and estrogen receptor status, disease-specific mortality was similar in women who underwent hormonal FP (adjusted hazard ratio [aHR], 0.59; 95% CI, 0.32-1.09), women who underwent nonhormonal FP (aHR, 0.51; 95% CI, 0.20-1.29), and women who were not exposed to FP (reference). In a subcohort with detailed data on relapse, adjusted rate of disease-specific mortality and relapse were also similar among the groups who underwent hormonal FP (aHR, 0.81; 95% CI, 0.49-1.37), underwent nonhormonal FP (aHR, 0.75; 95% CI, 0.35-1.62), and were not exposed to FP (reference). Conclusions and Relevance: In this cohort study, FP with or without hormonal stimulation was not associated with any increased risk of relapse or disease-specific mortality in women with BC. Results of this study provide much needed additional evidence on the safety of FP procedures in women with BC and may influence current health care practice to the benefit of young women with BC who wish to preserve their fertility.

Dissecting Tumor-Immune Microenvironment in Breast Cancer at a Spatial and Multiplex Resolution.

The tumor immune microenvironment (TIME) is an important player in breast cancer pathophysiology. Surrogates for antitumor immune response have been explored as predictive biomarkers to immunotherapy, though with several limitations. Immunohistochemistry for programmed death ligand 1 suffers from analytical problems, immune signatures are devoid of spatial information and histopathological evaluation of tumor infiltrating lymphocytes exhibits interobserver variability. Towards improved understanding of the complex interactions in TIME, several emerging multiplex in situ methods are being developed and gaining much attention for protein detection. They enable the simultaneous evaluation of multiple targets in situ, detection of cell densities/subpopulations as well as estimations of functional states of immune infiltrate. Furthermore, they can characterize spatial organization of TIME-by cell-to-cell interaction analyses and the evaluation of distribution within different regions of interest and tissue compartments-while digital imaging and image analysis software allow for reproducibility of the various assays. In this review, we aim to provide an overview of the different multiplex in situ methods used in cancer research with special focus on breast cancer TIME at the neoadjuvant, adjuvant and metastatic setting. Spatial heterogeneity of TIME and importance of longitudinal evaluation of TIME changes under the pressure of therapy and metastatic progression are also addressed.

Women with short survival after diagnosis of metastatic breast cancer: a population-based registry study.

PURPOSE: Despite therapeutic advances, overall survival of metastatic breast cancer (MBC) at the population level has seen little improvement over the past decades. Aggressive tumor biology or delay in access to cancer care might be contributing factors. With this retrospective population-based study we aimed to quantify and characterize patients with very short survival time following MBC diagnosis. METHODS: Women diagnosed with MBC between Jan 1st, 2005 and Dec 31st, 2016 were identified using the population-based Stockholm-Gotland breast cancer registry. Data regarding demographic and clinicopathological characteristics, survival, and treatment were extracted retrospectively from the registry and from patient charts. Patients who died within 90 days following diagnosis of MBC were identified and their characteristics were compared with all other patients diagnosed with MBC during the same period. RESULTS: Between 2005 and 2016, 3124 patients were diagnosed with MBC, of whom 498 (16.2%) died within 90 days of diagnosis. Nearly half (N = 233) did not receive any antitumoral treatment. Patients with short survival were older (p < 0.001), had higher primary tumor grade (p < 0.001), higher clinical stage at primary diagnosis (p = 0.002), and more often estrogen receptor (ER)-negative breast cancer (p < 0.001). Visceral metastases were more frequent (p < 0.001) and patients with short survival received adjuvant chemotherapy (p < 0.001) to a lesser extent compared to patients with a better prognosis. In multivariable analysis older age, time period of diagnosis, metastasis site, adjuvant chemotherapy, and primary tumor grade were independent predictors for short survival, whereas ER status was not. CONCLUSION: Nearly one out of six patients with MBC survive less than 3 months after diagnosis. Our findings demonstrate a different spectrum of MBC at population level and can potentially inform on individualized follow-up strategies and treatment algorithms.

Risk of heart disease following treatment for breast cancer - results from a population-based cohort study.

Background: There is a rising concern about treatment-associated cardiotoxicities in breast cancer patients. This study aimed to determine the time- and treatment-specific incidence of arrhythmia, heart failure, and ischemic heart disease in women diagnosed with breast cancer. Methods: A register-based matched cohort study was conducted including 8015 breast cancer patients diagnosed from 2001 to 2008 in the Stockholm-Gotland region and followed up until 2017. Time-dependent risks of arrhythmia, heart failure, and ischemic heart disease in breast cancer patients were assessed using flexible parametric models as compared to matched controls from general population. Treatment-specific effects were estimated in breast cancer patients using Cox model. Results: Time-dependent analyses revealed long-term increased risks of arrhythmia and heart failure following breast cancer diagnosis. Hazard ratios (HRs) within the first year of diagnosis were 2.14 (95% CI = 1.63-2.81) for arrhythmia and 2.71 (95% CI = 1.70-4.33) for heart failure. HR more than 10 years following diagnosis was 1.42 (95% CI = 1.21-1.67) for arrhythmia and 1.28 (95% CI = 1.03-1.59) for heart failure. The risk for ischemic heart disease was significantly increased only during the first year after diagnosis (HR = 1.45, 95% CI = 1.03-2.04). Trastuzumab and anthracyclines were associated with increased risk of heart failure. Aromatase inhibitors, but not tamoxifen, were associated with risk of ischemic heart disease. No increased risk of heart disease was identified following locoregional radiotherapy. Conclusions: Administration of systemic adjuvant therapies appears to be associated with increased risks of heart disease. The risk estimates observed in this study may aid adjuvant therapy decision-making and patient counseling in oncology practices. Funding: This work was supported by the Swedish Research Council (grant no: 2018-02547); Swedish Cancer Society (grant no: CAN-19-0266); and FORTE (grant no: 2016-00081).