Comprehensive Analysis of CXCR4, JUNB, and PD-L1 Expression in Circulating Tumor Cells (CTCs) from Prostate Cancer Patients.

CXCR4, JUNB and PD-L1 are implicated in cancer progression and metastasis. The current study investigated these biomarkers in CTCs isolated from metastatic prostate cancer (mPCa) patients at the RNA and protein levels. CTCs were isolated from 48 mPCa patients using the Ficoll density gradient and ISET system (17 out of 48). The (CK/PD-L1/CD45) and (CK/CXCR4/JUNB) phenotypes were identified using two triple immunofluorescence stainings followed by VyCAP platform analysis. Molecular analysis was conducted with an EpCAM-dependent method for 25/48 patients. CK-8, CK-18, CK-19, JUNB, CXCR4, PD-L1, and B2M (reference gene) were analyzed with RT-qPCR. The (CK+/PD-L1+/CD45-) and the (CK+/CXCR4+/JUNB+) were the most frequent phenotypes (61.1% and 62.5%, respectively). Furthermore, the (CK+/CXCR4+/JUNB-) phenotype was correlated with poorer progression-free survival [(PFS), HR: 2.5, p = 0.049], while the (CK+/PD-L1+/CD45-) phenotype was linked to decreased overall survival [(OS), HR: 262.7, p = 0.007]. Molecular analysis revealed that 76.0% of the samples were positive for CK-8,18, and 19, while 28.0% were positive for JUNB, 44.0% for CXCR4, and 48.0% for PD-L1. Conclusively, CXCR4, JUNB, and PD-L1 were highly expressed in CTCs from mPCa patients. The CXCR4 protein expression was associated with poorer PFS, while PD-L1 was correlated with decreased OS, providing new biomarkers with potential clinical relevance.

Newly detected diabetes mellitus patients with acute coronary syndrome have an adverse cardiometabolic profile similar to patients with prior diabetes and a more extensive ischemic myocardial insult.

AIMS: The impact of newly detected diabetes mellitus (NDDM) on metabolic parameters and extent of myocardial necrosis in patients with acute coronary syndrome (ACS) is not fully explored. We examined the impact of NDDM on cardiometabolic characteristics and myocardial necrosis in ACS patients. METHODS: CALLINICUS-Hellas Registry is an ongoing prospective multicenter observational study evaluating the adherence to lipid-lowering therapy (LLT) among ACS patients in Greece. Three groups were created: a) patients with NDDM (abnormal fasting glucose, HbA1c ≥ 6.5 % and no previous history of DM), b) patients without known DM and HbA1c < 6.5 % (non-DM) and c) patients with prior DM. RESULTS: The prevalence of NDDM among 1084 patients was 6.9 %. NDDM patients had lower HDL-C [38 (32-45) vs 42 (36-50) mg/dL] and higher triglycerides levels [144 (104-231) vs 115 (87-152) mg/dL] compared to non-DM patients (p < 0.05). NDDM patients featured both higher body mass index [29.5 (26.4-34.3) vs 27.1 (24.9-29.9) kg/m2] and waist circumference [107 (100-114) vs 98 (91-106) cm] compared to non-DM patients (p < 0.05). In addition, NDDM patients had more extensive myocardial necrosis than patients with prior DM. CONCLUSIONS: ACS patients with NDDM have an adverse cardiometabolic profile similar to patients with prior DM and have more extensive myocardial insult.

Injuries and Persistent Pain in Elite Adolescent Archery Athletes: A Cross-Sectional Epidemiological Study.

This cross-sectional epidemiological study aimed to evaluate the prevalence of injuries among young archers engaged in high-intensity training during the European Youth Championship. A total of 200 participants (104 males/96 females) from 34 countries were included, with a mean age of 16.9 years and average competitive experience of 6.5 years. Structured questionnaires, administered by four physiotherapist interviewers, gathered comprehensive data. Results revealed that 43.5% of participants experienced shoulder pain during training, highlighting the vulnerability of upper limbs in archers. Additionally, 30% required medications to facilitate training, underscoring the impact of injuries on continued participation. Physiotherapy was utilized by 52.3% of participants, emphasizing the need for therapeutic intervention. Furthermore, 31.8% had to cease training due to injuries, indicating a substantial hindrance to athletic progression. The mean pain duration was 3.9 months, with an average intensity of 5.94, and 8% exhibited symptoms of central sensitization. In conclusion, this study demonstrates a noteworthy prevalence of injuries, particularly in the upper limbs, among young archers undergoing intensive training. The findings underscore the importance of targeted injury prevention strategies and comprehensive rehabilitation approaches to ensure the well-being and sustained participation of young athletes in competitive archery.

ES-SCLC Patients with PD-L1+ CTCs and High Percentages of CD8+PD-1+T Cells in Circulation Benefit from Front-Line Immunotherapy Treatment.

SCLC is an aggressive cancer type with high metastatic potential and bad prognosis. CTCs are a valuable source of tumor cells in blood circulation and are among the major contributors to metastasis. In this study we evaluated the number of CTCs that express PD-L1 in treatment-naïve ES-SCLC patients receiving ICI in a front-line setting. Moreover, we explored the percentages of different immune T-cell subsets in circulation to assess their potential role in predicting responses. A total of 43 patients were enrolled-6 of them with LS-SCLC, and 37 with ES-SCLC disease. In addition, PBMCs from 10 healthy donors were used as a control group. Different T-cell subtypes were examined through multicolor FACS analysis and patients' CTCs were detected using immunofluorescence staining. SCLC patients had higher percentages of PD-1-expressing CD3+CD4+ and CD3+CD8+ T-cells, as well as elevated PD-1 protein expression compared to healthy individuals. Additionally, in ES-SCLC patients, a positive correlation between CD3+CD8+PD-1+ T-cells and PD-L1+ CTCs was detected. Importantly, patients harboring higher numbers of CD3+CD8+PD-1+ T-cells together with PD-L1+CTCs had a survival advantage when receiving front-line immunotherapy. Thus, this study proposes, for first time possible, immune cell-CTCs interaction, as well as a potential novel clinical biomarker for ICI responses in ES-SCLC patients.

Prognostic Role of Circulating Tumor Cells in Patients with Metastatic Castration-Resistant Prostate Cancer Receiving Cabazitaxel: A Prospective Biomarker Study.

RATIONAL: Circulating tumor cells (CTCs) appear to be a promising tool for predicting the clinical outcome and monitoring the response to treatment in patients with solid tumors. The current study assessed the clinical relevance of monitoring CTCs in patients with metastatic castration resistant prostate cancer (mCRPC) treated with cabazitaxel. PATIENTS AND METHODS: Patients with histologically confirmed mCRPC who were previously treated with a docetaxel-containing regimen and experienced disease progression were enrolled in this multicenter prospective study. CTC counts were enumerated using the CellSearch system at baseline (before cabazitaxel initiation), after one cabazitaxel cycle (post 1st cycle) and at disease progression (PD). Patients were stratified into predetermined CTC-positive and CTC-negative groups. The phenotypic characterization was performed using double immunofluorescence staining with anti-CKs and anti-Ki67, anti-M30 or anti-vimentin antibodies. RESULTS: The median PFS and OS were 4.0 (range, 1.0-17.9) and 14.5 (range, 1.2-33.9) months, respectively. At baseline, 48 out of 57 (84.2%) patients had ≥1 CTCs/7.5 mL of peripheral blood (PB) and 37 (64.9%) had ≥5 CTCs/7.5 mL of PB. After one treatment cycle, 30 (75%) out of the 40 patients with available measurements had ≥1 detectable CTC/7.5 mL of PB and 24 (60%) ≥ 5CTCs/7.5 mL of PB; 12.5% of the patients with detectable CTCs at the baseline sample had no detectable CTCs after one treatment cycle. The detection of ≥5CTCs/7.5 mL of PB at baseline and post-cycle 1 was associated with shorter PFS and OS (p = 0.002), whereas a positive CTC status post-cycle 1 strongly correlated with poorer OS irrespective of the CTC cut-off used. Multivariate analysis revealed that the detection of non-apoptotic (CK+/M30-) CTCs at baseline is an independent predictor of shorter OS (p = 0.005). CONCLUSIONS: In patients with mCRPC treated with cabazitaxel, CTC counts both at baseline and after the first cycle retain their prognostic significance, implying that liquid biopsy monitoring might serve as a valuable tool for predicting treatment efficacy and survival outcomes.

The Utility of NGS Analysis in Homologous Recombination Deficiency Tracking.

Several tumor types have been efficiently treated with PARP inhibitors (PARPis), which are now approved for the treatment of ovarian, breast, prostate, and pancreatic cancers. The BRCA1/2 genes and mutations in many additional genes involved in the HR pathway may be responsible for the HRD phenomenon. The aim of the present study was to investigate the association between genomic loss of heterozygosity (gLOH) and alterations in 513 genes with targeted and immuno-oncology therapies in 406 samples using an NGS assay. In addition, the %gLOHs of 24 samples were calculated using the Affymetrix technology in order to compare the results obtained via the two methodologies. HR variations occurred in 20.93% of the malignancies, while BRCA1/2 gene alterations occurred in 5.17% of the malignancies. The %LOH was highly correlated with alterations in the BRCA1/2 genes, since 76.19% (16/21) of the BRCA1/2 positive tumors had a high %LOH value (p = 0.007). Moreover, the LOH status was highly correlated with the TP53 and KRAS statuses, but there was no association with the TMB value. Lin's concordance correlation coefficient for the 24 samples simultaneously examined via both assays was 0.87, indicating a nearly perfect agreement. In conclusion, the addition of gLOH analysis could assist in the detection of additional patients eligible for treatment with PARPis.

Functional Analysis of Viable Circulating Tumor Cells from Triple-Negative Breast Cancer Patients Using TetherChip Technology.

Metastasis, rather than the growth of the primary tumor, accounts for approximately 90% of breast cancer patient deaths. Microtentacles (McTNs) formation represents an important mechanism of metastasis. Triple-negative breast cancer (TNBC) is the most aggressive subtype with limited targeted therapies. The present study aimed to isolate viable circulating tumor cells (CTCs) and functionally analyze them in response to drug treatment. CTCs from 20 TNBC patients were isolated and maintained in culture for 5 days. Biomarker expression was identified by immunofluorescence staining and VyCap analysis. Vinorelbine-induced apoptosis was evaluated based on the detection of M30-positive cells. Our findings revealed that the CTC absolute number significantly increased using TetherChips analysis compared to the number of CTCs in patients' cytospins (p = 0.006) providing enough tumor cells for drug evaluation. Vinorelbine treatment (1 h) on live CTCs led to a significant induction of apoptosis (p = 0.010). It also caused a significant reduction in Detyrosinated α-tubulin (GLU), programmed death ligand (PD-L1)-expressing CTCs (p < 0.001), and disruption of McTNs. In conclusion, this pilot study offers a useful protocol using TetherChip technology for functional analysis and evaluation of drug efficacy in live CTCs, providing important information for targeting metastatic dissemination at a patient-individualized level.

Investigation of Clinically Significant Molecular Aberrations in Patients with Prostate Cancer: Implications for Personalized Treatment, Prognosis and Genetic Testing.

The data on tumor molecular profiling of European patients with prostate cancer is limited. Our aim was to evaluate the prevalence and prognostic and predictive values of gene alterations in unselected patients with prostate cancer. The presence of gene alterations was assessed in patients with histologically confirmed prostate cancer using the ForeSENTIA® Prostate panel (Medicover Genetics), targeting 36 clinically relevant genes and microsatellite instability testing. The primary endpoint was the prevalence of gene alterations in homologous recombination repair (HRR) genes. Overall, 196 patients with prostate cancer were evaluated (median age 72.2 years, metastatic disease in 141 (71.9%) patients). Gene alterations were identified in 120 (61%) patients, while alteration in HRR genes were identified in 34 (17.3%) patients. The most commonly mutated HRR genes were ATM (17, 8.7%), BRCA2 (9, 4.6%) and BRCA1 (4, 2%). The presence of HRR gene alterations was not associated with advanced stage (p = 0.21), age at diagnosis (p = 0.28), Gleason score (p = 0.17) or overall survival (HR 0.72; 95% CI: 0.41-1.26; p = 0.251). We identified clinically relevant somatic gene alterations in European patients with prostate cancer. These molecular alterations have prognostic significance and therapeutic implications and/or may trigger genetic testing in selected patients. In the era of precision medicine, prospective research on the predictive role of these alterations for innovative treatments or their combinations is warranted.

Successful Shrinkage of a Giant Cutaneous Squamous Cell Carcinoma with Immunotherapy in a Kidney Transplant Recipient.

A 56-year-old male living donor kidney transplant recipient presented with a giant cutaneous squamous cell carcinoma in his right parotid region. Programmed radiotherapy had been previously terminated due to lesion ulceration and bleeding. He was characterized as a terminal case. We applied cemiplimab, which is an immune checkpoint inhibitor against the pro-grammed cell death receptor PD-1. After 6 months, the cutaneous squamous cell carcinoma had shrunk and had stopped bleeding. The patient was treated with methylprednisolone, cyclosporine, and mycophenolate mofetil during this period. He had 2 rejection episodes defined as doubling baseline serum creatinine with no other explanation. Both episodes were successfully treated with intravenous methylprednisolone, while immunotherapy was postponed for 10 days. In both cases, serum creatinine returned to baseline within 1 week. Immune checkpoint inhibitors are indicated for invasive cutaneous squamous cell carcinoma therapy, and the risk of acute rejection should not prevent the use of these agents in kidney transplant recipients, because immune checkpoint inhibitors may enhance the quantity and quality of life of such patients.

Endobronchial Radiofrequency Ablation for pulmonary nodules with Radial-Ebus and Navigation: Pros and Cons.

Introduction: Pulmonary nodules are common in the everyday clinical practice. There is always a diagnostic issue with this imaging finding. Based on the size we can use a variety of imaging and diagnostic techniques. Moreover; in the case of primary lung cancer or metastasis we can use radiofrequency ablation endobronchially. Patients and Methods: We used the radial-endobronchial ultrasound with C-arm and Archemedes, Bronchus electromagnetic navigation in order to acquire biopsy sample and we also used rapid on-site evaluation as a rapid diagnosis for pulmonary nodules. After rapid diagnosis we used the radiofrequency ablation catheter in order to ablate central pulmonary nodules. Results: Both techniques provide efficient navigation, however, with the Bronchus system less time is needed. The new radiofrequency ablation catheter provides efficient results in central lesions with low watts ≤40. Conclusion: We provided in our research a protocol to diagnose and treat such lesions. Future larger studies will provide more data on this subject.

Immune Checkpoint and EMT-Related Molecules in Circulating Tumor Cells (CTCs) from Triple Negative Breast Cancer Patients and Their Clinical Impact.

Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype. There are few targeted therapies for these patients, leading to an unmet need for new biomarkers. The present study aimed to investigate the expression of PD-L1, CTLA-4, GLU, and VIM in CTCs of TNBC patients. Ninety-five patients were enrolled in this study: sixty-four TNBC and thirty-one luminal. Of these patients, 60 were in the early stage, while 35 had metastatic disease. Protein expression was identified by immunofluorescence staining experiments and VyCAP analysis. All the examined proteins were upregulated in TNBC patients. The expression of the GLU+VIM+CK+ phenotype was higher (50%) in metastatic TNBC compared to early TNBC patients (17%) (p = 0.005). Among all the BC patients, a significant correlation was found between PD-L1+CD45-CK+ and CTLA-4+CD45-CK+ phenotypes (Spearman test, p = 0.024), implying an important role of dual inhibition in BC. Finally, the phenotypes GLU+VIM+CK+ and PD-L1+CD45-CK+ were associated with shorter OS in TNBC patients (OS: log-rank p = 0.048, HR = 2.9, OS: log-rank p < 0.001, HR = 8.7, respectively). Thus, PD-L1, CTLA-4, GLU, and VIM constitute significant biomarkers in TNBC associated with patients' outcome, providing new therapeutic targets for this difficult breast cancer subtype.

Prognostic Significance of Risk Factors and Biomarkers in Patients Hospitalized for Cardiorenal Syndromes: A Pilot Study.

BACKGROUND: Cardiorenal syndromes (CRS), involving the heart-kidney cross-talk and the activation of neurohumoral and inflammatory pathways, are an entity characterized by high morbidity and mortality. OBJECTIVE: To evaluate the prognostic role of risk factors and biomarkers in patients hospitalized for CRS. METHODS: In this observational cohort study, 100 consecutive patients hospitalized for CRS were enrolled. Socio-demographic characteristics, personal medical history, and prior medication use were recorded upon admission, and echocardiography was performed. Moreover, an array of blood markers were measured. The endpoint of interest was a composite of death or dialysis dependence at discharge. RESULTS: Patients were classified into two groups; Group 1 (N= 52): discharged being dialysis-independent, Group 2 (N=48): death/dialysis dependence at discharge. No significant differences were detected in baseline characteristics between the two groups. Group 2 patients used renin-angiotensin-aldosterone system blockers (RAASb) less often and more frequently presented with oliguria/anuria. Group 2 patients had significantly lower hemoglobin, serum albumin, and 25-hydroxy-vitamin D (25(OH)D). At the same time, serum phosphate, potassium, and parathyroid hormone (PTH) were significantly higher in Group 2 patients. In a multivariate regression analysis, lack of prior RAASb and lower 25(OH)D levels were independently associated with an increased risk of death or dialysis dependence at discharge. 25(OH)D/PTH ratio was the most accurate predictor of the composite endpoint (Sensitivity: 79.4%, Specificity: 70.4%). CONCLUSION: Lack of prior RAASb use, high PTH, low 25(OH)D levels, and low 25(OH) D/PTH ratio are associated with a poor prognosis in patients hospitalized for CRS.

Emerging Role of YAP and the Hippo Pathway in Prostate Cancer.

The Hippo pathway regulates and contributes to several hallmarks of prostate cancer (PCa). Although the elucidation of YAP function in PCa is in its infancy, emerging studies have shed light on the role of aberrant Hippo pathway signaling in PCa development and progression. YAP overexpression and nuclear localization has been linked to poor prognosis and resistance to treatment, highlighting a therapeutic potential that may suggest innovative strategies to treat cancer. This review aimed to summarize available data on the biological function of the dysregulated Hippo pathway in PCa and identify knowledge gaps that need to be addressed for optimizing the development of YAP-targeted treatment strategies in patients likely to benefit.

Complications of Totally Implantable Central Venous Catheters (Ports) Inserted via the Internal Jugular Vein Under Ultrasound and Fluoroscopy Guidance in Adult Oncology Patients: A Single-Center Experience.

Introduction In this retrospective study, the safety and complication rates of port implantations via the internal jugular vein under ultrasound and fluoroscopy guidance in adult oncology patients were analyzed. Material and methods Eight hundred seven ports implanted in 799 adult oncology patients at a tertiary Oncology-Anticancer Hospital during a 36-month period from January 1, 2017 to December 31, 2019 were retrospectively reviewed. Data acquisition was obtained until December 31, 2020. All procedures were performed by two specialized interventional radiologists under ultrasound and fluoroscopy guidance. The vein access was via the internal jugular vein. Catheter days (the total number of days of maintenance of the port by all of the patients until removal, death, or December 31, 2020), technical success rates, and complication rates were evaluated based on the interventional radiological reports and patient medical records. Multivariate analysis regarding patients such as age, sex, body mass index (BMI), marital status, educational level, cancer type, side of insertion, diameter of internal jugular vein, diabetes, anticoagulants/antiplatelets, purpose of implantation, and catheter material as to the risk of complications was conducted. Results A total of 369,329 catheter maintenance days were observed (457.7±345.0). The technical success rate was 99.9%, and a total of 85 (10.5%) complications occurred, of which 24 (28.2%) occurred early (<30 days) and the remaining 61 (71.8%) were late (>30 days) complications. Specifically, 28 (3.5%) were catheter-related thrombosis (CRT), 27 (3.4%) related to infection, 17 (2.1%) were mechanical complications (16 fibrin sheath formation and one catheter occlusion), six (0.7%) related to catheter migration, four (0.5%) related to incision healing problems, and the remaining three (0.4%) related to ischemic skin necrosis. Forty-seven (5.8%) ports were removed due to complications. On multivariate analysis, cancer type was found as a risk factor for the development of a complication. Additionally, there was an indication that hematologic malignancy is related to infection. Conclusion Placement of ports via the internal jugular vein under ultrasound and fluoroscopy guidance is a safe procedure, with low rates of early and late complications.

Comment on "Disease exacerbation is common in inflammatory bowel disease patients treated with immune checkpoint inhibitors for malignancy".

We recently read with interest the original research article entitled "Disease exacerbation is common in inflammatory bowel disease patients treated with immune checkpoint inhibitors for malignancy". The abovementioned article is an observational retrospective cohort study, which could be of particular value for clinicians to understand how immunotherapy affects pre-existing enteral disease in inflammatory bowel disease patients. Although we appreciate the endeavor of Samuel Rubin et al, based on our in-depth analysis, we detected a potential shortcoming in this article; thus, we present our comments in this letter. If the authors contemplate these comments on their relevant research, we believe that their contribution would be considerable for future studies.

PD-L1/pS6 in Circulating Tumor Cells (CTCs) during Osimertinib Treatment in Patients with Non-Small Cell Lung Cancer (NSCLC).

The PD-1/PD-L1 axis provides CTCs an escape route from the immune system. Phosphorylation of the ribosomal protein S6 is implicated in the same pathway, following mTOR activation. The aim of the study was to investigate the expression of PD-L1 and pS6 in CTCs from NSCLC patients under Osimertinib treatment at a single cell level. CTCs were isolated using ISET from NSCLC patients' blood [37 at baseline, 25 after the 1st cycle, and 23 at the end of treatment (EOT)]. Staining was performed using immunofluorescence. Cytokeratin-positive (CK+) CTCs were detected in 62% of patients. CK+PD-L1+CD45− and CK+pS6+ phenotypes were detected in 38% and 41% of the patients at baseline, in 28% and 32% after 1st cycle, and in 30% and 35% at EOT, respectively. Spearman's analysis revealed statistically significant correlations between PD-L1 and pS6 phenotypes at all time points. Survival analysis revealed that CK+pS6+ (p = 0.003) and CKlowpS6+ (p = 0.021) phenotypes after 1st cycle were related to significantly decreased one-year progression-free survival (PFS12m) and PFS, respectively. CK+PD-L1+CD45−phenotype at baseline and after 1st cycle showed a trend for decreased PFS12m. Increased expression of PD-L1/pS6 in CTCs of Osimertinib-treated NSCLC patients implies the activation of the corresponding pathway, which is potentially associated with poor clinical outcomes.

Objective Response to First-Line Treatment as a Predictor of Overall Survival in Metastatic Breast Cancer: A Retrospective Analysis from Two Centers over a 25-Year Period.

Introduction: The purpose of this study was to study the efficacy of subsequent treatment lines for metastatic breast cancer (MBC), as well as the association between radiologic objective response rate (ORR) and overall survival (OS). Methods: In this retrospective study, consecutive patients treated for MBC in two centers in Greece from January 1, 1992, to December 31, 2016, were identified and clinicopathologic data regarding tumor characteristics and administered treatments were collected. The efficacy per treatment line in terms of ORR, progression-free survival (PFS) and OS, as well as the prognostic value of ORR at first line were investigated. Results: A total of 977 patients with MBC were identified; 950 received any treatment. At first line, ORR was 43.5%, PFS 11.4 months (95% CI 10.4-12.4), and median OS 52.4 months (95% CI 47.7-57.1). Lower ORR and shorter PFS were observed with each subsequent line. Median OS was significantly longer for patients that had an objective response at first line, 61.9 months (95% CI 51.1-69.7) for responders versus 41.3 months (95% CI 44.1-63.3) for nonresponders (p < 0.001). In multivariable analysis, failure to achieve an objective response was an independent predictor of poor survival (hazard ratio 1.70, 95% CI 1.34-2.15, p < 0.001). Conclusion: Late treatment lines for MBC seem to have limited efficacy, while response to first-line therapy is associated with long-term survival. The latter should be considered in the treatment strategy of patients with MBC.

PARP-1 Expression and BRCA1 Mutations in Breast Cancer Patients' CTCs.

BRCA1 and PARP are involved in DNA damage repair pathways. BRCA1 mutations have been linked to higher likelihood of triple negative breast cancer (TNBC). The aim of the study was to determine PARP-1 expression and BRCA1 mutations in circulating tumor cells (CTCs) of BC patients. Fifty patients were enrolled: 23 luminal and 27 TNBC. PARP expression in CTCs was identified by immunofluorescence. Genotyping was performed by PCR-Sanger sequencing in the same samples. PARP-1 expression was higher in luminal (61%) and early BC (54%), compared to TNBC (41%) and metastatic (33%) patients. In addition, PARP-1 distribution was mostly cytoplasmic in luminal patients (p = 0.024), whereas it was mostly nuclear in TNBC patients. In cytokeratin (CK)-positive patients, those with the CK+PARP+ phenotype had longer overall survival (OS, log-rank p = 0.046). Overall, nine mutations were detected; M1 and M2 were completely new and M4, M7 and M8 were characterized as pathogenic. M7 and M8 were predominantly found in metastatic TNBC patients (p = 0.014 and p = 0.002). Thus, PARP-1 expression and increased mutagenic burden in TNBC patients' CTCs, could be used as an indicator to stratify patients regarding therapeutic approaches.