A 53-Year-Old Woman with Axillary Lymphadenopathy.

AbstractMorning Report is a time-honored tradition where physicians-in-training present cases to their colleagues and clinical experts to collaboratively examine an interesting patient presentation. The Morning Report section seeks to carry on this tradition by presenting a patient's chief concern and story, inviting the reader to develop a differential diagnosis and discover the diagnosis alongside the authors of the case. This report examines the story of a 53-year-old woman with a history of breast cancer who presented with abnormal axillary lymph nodes detected on surveillance imaging. Using history, physical examination, and diagnostic workup, an illness script for her presentation emerges. A differential diagnosis is developed and refined until a final diagnosis is confirmed.

Long-term efficacy of fractional microneedle radiofrequency versus botulinum toxin-A in primary axillary hyperhidrosis: a randomized controlled trial.

Primary axillary hyperhidrosis is an idiopathic disorder that creates severe psycho-social burden due to excessive uncontrolled sweating. Various therapeutic agents have been described, but each has its own limitations. The use of fractional microneedling radiofrequency has emerged lately with promising results. This study aimed to determine the efficacy and safety of fractional microneedle radiofrequency in comparison to Botulinum toxin-A (BT-A) in patients with primary axillary hyperhidrosis. In this randomized controlled clinical trial, 20 patients (40 sides) were randomized to either fractional microneedle radiofrequency (4 sessions at 3-week intervals) or BT-A (single session), where each side received one of the treatment modalities. Efficacy was measured at 3, 6 and 12 months using Minor's starch iodine test, HDSS score, Hqol questionnaire, and patient satisfaction. Fractional microneedle radiofrequency, although showed moderate efficacy, is inferior to BT-A regarding longitudinal efficacy at 12 months, as well as patients' satisfaction. Both treatment modalities showed to be equally safe, but fractional microneedle radiofrequency procedure was substantially more painful. In conclusion, fractional microneedle radiofrequency does not offer a better substitute to BT-A in primary axillary hyperhidrosis. BT-A shows higher efficacy, is less painful, less expensive, and needs a smaller number of sessions.

Identifying Key Genes Involved in Axillary Lymph Node Metastasis in Breast Cancer Using Advanced RNA-Seq Analysis: A Methodological Approach with GLMQL and MAS.

Our study aims to address the methodological challenges frequently encountered in RNA-Seq data analysis within cancer studies. Specifically, it enhances the identification of key genes involved in axillary lymph node metastasis (ALNM) in breast cancer. We employ Generalized Linear Models with Quasi-Likelihood (GLMQLs) to manage the inherently discrete and overdispersed nature of RNA-Seq data, marking a significant improvement over conventional methods such as the t-test, which assumes a normal distribution and equal variances across samples. We utilize the Trimmed Mean of M-values (TMMs) method for normalization to address library-specific compositional differences effectively. Our study focuses on a distinct cohort of 104 untreated patients from the TCGA Breast Invasive Carcinoma (BRCA) dataset to maintain an untainted genetic profile, thereby providing more accurate insights into the genetic underpinnings of lymph node metastasis. This strategic selection paves the way for developing early intervention strategies and targeted therapies. Our analysis is exclusively dedicated to protein-coding genes, enriched by the Magnitude Altitude Scoring (MAS) system, which rigorously identifies key genes that could serve as predictors in developing an ALNM predictive model. Our novel approach has pinpointed several genes significantly linked to ALNM in breast cancer, offering vital insights into the molecular dynamics of cancer development and metastasis. These genes, including ERBB2, CCNA1, FOXC2, LEFTY2, VTN, ACKR3, and PTGS2, are involved in key processes like apoptosis, epithelial-mesenchymal transition, angiogenesis, response to hypoxia, and KRAS signaling pathways, which are crucial for tumor virulence and the spread of metastases. Moreover, the approach has also emphasized the importance of the small proline-rich protein family (SPRR), including SPRR2B, SPRR2E, and SPRR2D, recognized for their significant involvement in cancer-related pathways and their potential as therapeutic targets. Important transcripts such as H3C10, H1-2, PADI4, and others have been highlighted as critical in modulating the chromatin structure and gene expression, fundamental for the progression and spread of cancer.

Prediction of the number of positive axillary lymph nodes according to sentinel lymph node involvement and biological subtypes in patients receiving neoadjuvant chemotherapy.

BACKGROUND: Sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) for assessing axillary lymph node status in clinically node-negative breast cancer patients. However, the approach to axillary surgery after neoadjuvant treatment is still controversial. In the present study, our objective was to predict the pathological nodal stage based on SLNB results and the clinicopathological characteristics of patients who initially presented with clinical N1 positivity but whose disease status was converted to clinical N0 after neoadjuvant chemotherapy (NAC). MATERIALS AND METHODS: After NAC, 150 clinically node-negative patients were included. The relationships between clinicopathologic parameters and the number of positive lymph nodes in SLNBs and ALNDs were assessed through binary/multivariate logistic regression analysis. RESULTS: Among 150 patients, 78 patients had negative SLNBs, and 72 patients had positive SLNBs. According to the ALND data of 21 patients with SLNB1+, there was no additional node involvement (80.8%), 1-2 lymph nodes were positive in 5 patients (19.2%), and no patient had ≥ 3 lymph nodes involved. Following the detection of SLNB1 + positivity, the rate of negative non-sentinel nodes were 75% in the luminal A/B subgroup, 100% in the HER-2-positive subgroup, and 100% in the triple-negative subgroup. Patients with a lower T stage (T1-3 vs. T4), fewer than 4 clinical nodes before NAC (< 4 vs. ≥4), and a decreased postoperative Ki-67 index (< 10% vs. stable/increase) were included. According to both univariate and multivariate analyses, being in the triple-negative or HER2-positive subgroup, compared to the luminal A/B subgroup (luminal A/B vs. HER2-positive/triple-negative), was found to be predictive of complete lymph node response. CONCLUSION: The number of SLNB-positive nodes, tumor-related parameters, and response to treatment may predict no additional nodes to be positive at ALND.

Using an Innovative Protective Sleeve to Reduce Skin Compression Complications in Axillary Osmidrosis Surgery.

Osmidrosis is a condition characterized by malodorous sweat production in the armpits that often necessitates surgical intervention with tie-over bandages in the axillary area. Standard tie-over bandages may cause skin compression-related complications, such as bruising and skin erosion. To address this issue, we developed a novel technique using a modified protective sleeve. We conducted an observational study involving 60 patients undergoing axillary osmidrosis surgery and divided them into groups. In the experimental group we used a novel technique that included using a modified protective sleeve secured with 4-0 silk sutures. In the control group we used standard tie-over bandages. We created the protective sleeve from the tail of a 3 mL syringe by drilling holes on both sides and securing it onto a 10 mm-wide Penrose drain. We threaded sutures through the holes and provided padding between the sutures and the skin. We assessed primary outcomes of bruising and skin breakdown at eight anchoring sites. We found that using the novel protective sleeve significantly reduced skin complications. Compared with standard bandages, the incidence of bruising was reduced by 83.33% (i.e., 16.7% vs 70%). The incidence of skin erosion was reduced by 75% (10% vs 40%). Notably, the control group exhibited delayed complications, such as hypertrophic scars.

A Rare Case of Axillary Extramammary Paget's Disease with an Underlying Adenocarcinoma.

Extramammary Paget's disease (EMPD) is an uncommon cutaneous neoplasm almost exclusively located in the vulvar, perianal, and male genitalia regions. Evaluation and management are complicated given the average delay in diagnosis is two years and approximately 30% of cases are associated with underlying malignancies. The axilla is a unique location for EMPD. We report a rare case of a 78-year-old male with axillary EMPD associated with an underlying adenocarcinoma. A 1-cm tender and pruritic erythematous plaque with surrounding erythema appeared in the patient's axilla. An irritated seborrheic keratosis secondarily impetiginized along with irritant contact dermatitis was suspected. Treatment of cefdinir and topical hydrocortisone failed and a biopsy was taken. Microscopic and immunohistochemical examination showed ulceration with an underlying proliferation of atypical glands (Figure 2A) and a nested intraepidermal proliferation with pagetoid spread (Figure 2B). The atypical cells were positive for gross cystic disease fluid protein 15 (Figure 2C), epithelial membrane antigen (Figure 2D), cytokeratin 5/6, and cytokeratin 7. These findings were supportive of an apocrine adenocarcinoma arising in association with EMPD. Wide location excision was performed. Screening for associated malignancies or lymphatic spread is the primary goal during evaluation. Outcomes are favorable when the primary neoplasm is of limited distribution. The accepted treatment for primary lesions is wide local excision, although anatomic tissue constraints necessitate further research into other treatment modalities. To our knowledge, this is the 14th reported case of axillary EMPD with an underlying adenocarcinoma which may help with identification and management of future cases.

[Own experience of indocyanine green use in the diagnosis and treatment of breast cancer in N.N. Petrov NMRC of Oncology]. / Sobstvennyi opyt ispol'zovaniya indotsianina zelenogo v diagnostike i lechenii raka molochnoi zhelezy v NMITs onkologii im. N.N. Petrova.

OBJECTIVE: To evaluate the possibility of using the method of sentinel lymph nodes (SLN) detection with indocyanine green (ICG) in patients with early breast cancer and its informativeness. MATERIAL AND METHODS: A «Determination of sentinel lymph nodes by fluorescence method intraoperatively with the use of indocyanine green¼ study, in which 168 patients are currently included, is being conducted in the clinic of the N.N. Petrov NMRC of Oncology from 2017 through the present. All patients who underwent biopsy of sentinel lymph nodes (BSLN) were primary with a T1-2N0M0 stage of process. RESULTS: The average number of axillary lymph nodes removed in BSLN was 3 (1-5). Accumulation of ICG was found in 147 (88%) patients, accumulation of labeled radiocolloid - in 137 (82%), in combination of ICG/radiocolloid - in 167 (99%) based on the results of imaging. CONCLUSION: The obtained results prove that the informativeness and relative simplicity of this method use allow its application in any hospital where breast cancer is surgically treated, as well as in the absence of radioisotopic equipment.

[Photon field junction for external beam radiotherapy of breast cancer involving axillary and supraclavicular lymph nodes]. / Koplanáris fotonmezok illesztése axilláris, illetve szupraklavikuláris nyirokcsomók régióját érinto emlodaganatok külso besugárzásánál.

We present evaluation of junction of coplanar external beam photon fields and its portal dosimetric analysis for breast cancer with positive lymph nodes. In our work, we compared twelve patients affected by breast cancer with axillary and supraclavicular lymph nodes, using conformal external beam plans from a dosimetric point of view. 3-3 plans were prepared per patient. Three methods were used for the conformal technique to investigate the potential of lymph nodes treatment field's collimations. During the evaluation of the portal dosimetry images, it was concluded that the junction plane at isocenter appeared as a discrete coldline, when fitted the regional field with or without collimation manually and by the software. However, the coverage of the isocenter plane is strongly influenced by the linear accelerator and the fitted field edges. Based on our results, in order to avoid uncertainties arising from field junctions and the overdosed areas of the target volume, it is more appropriate to choose another advanced irradiation technique such as intensity-modulated radiation therapy.

Ultrasound-Guided Fine Needle Biopsy of Human Axillary Lymph Nodes to Assess B Cell Responses to Vaccination.

Ultrasound-guided fine needle biopsy, also known as fine needle aspiration, of human axillary lymph nodes is a safe and effective procedure to assess the immune response within the lymph nodes following vaccination. Once acquired, lymph node cells can be characterized via flow cytometric immunophenotyping and/or single-cell RNA sequencing for gene expression and T and B cell receptors. Analysis of the immune cells from the lymph nodes enables the investigation of T and B cells that may interact at this site. These interactions may lead to germinal center formation and expansion, critical for the generation of effective immunity to vaccination. Directly studying the dynamic processes and interaction of the key cells has been challenging in humans due to the anatomically protected location of these cells. Here, we describe the methods involved in ultrasound-guided fine needle biopsy of human axillary lymph nodes in response to vaccination and subsequent analyses of the B cell populations.

Using surface-enhanced Raman scattering for simultaneous multiplex detection and quantification of thiols associated to axillary malodour.

Axillary malodour is caused by the microbial conversion of human-derived precursors to volatile organic compounds. Thiols strongly contribute to this odour but are hard to detect as they are present at low concentrations. Additionally, thiols are highly volatile and small making sampling and quantification difficult, including by gas chromatography-mass spectrometry. In this study, surface-enhanced Raman scattering (SERS), combined with chemometrics, was utilised to simultaneously quantify four malodourous thiols associated with axillary odour, both in individual and multiplex solutions. Univariate and multivariate methods of partial least squares regression (PLS-R) were used to calculate the limit of detection (LoD) and results compared. Both methods yielded comparable LoD values, with LoDs using PLS-R ranging from 0.0227 ppm to 0.0153 ppm for the thiols studied. These thiols were then examined and quantified simultaneously in 120 mixtures using PLS-R. The resultant models showed high linearity (Q2 values between 0.9712 and 0.9827 for both PLS-1 and PLS-2) and low values of root mean squared error of predictions (0.0359 ppm and 0.0459 ppm for PLS-1 and PLS-2, respectively). To test this approach further, these models were challenged with 15 new blind test samples, collected independently from the initial samples. This test demonstrated that SERS combined with PLS-R could be used to predict the unknown concentrations of these thiols in a mixture. These results display the ability of SERS for the simultaneous multiplex detection and quantification of analytes and its potential for future development for detecting gaseous thiols produced from skin and other body sites.

Treatment of Primary Axillary Hyperhidrosis with Two Doses of Botulinum Toxin A-Observational Study.

Hyperhidrosis (HH) is defined as the production of more sweat than is necessary for its thermoregulatory function, negatively affecting patients' quality of life and interfering with their social, work and family life. In this context, the aim of thisstudy was to evaluate the efficacy of two different doses of botulinum toxin type A (50 or 100 units) in each axilla in severe primary axillary hyperhidrosis. A descriptive, observational, cross-sectional and post-authorisation study was conducted onpatients referred to our department.Thirty-one patients with severe primary axillary hyperhidrosis were included, some of whom received more than one infiltration during the follow-up period, performing a total of 82 procedures. They were assigned by simple random sampling to two types of treatment: infiltration of 50 or 100 units (U) of botulinum toxin A per axilla.Hyperhidrosis severity was assessed using the Hyperhidrosis Disease Severity Scale (HDSS), and quality of life was assessed using the Dermatology Life Quality Index (DLQI) questionnaire. Onabotulinum toxin A infiltration reduced the severity of hyperhidrosis and improved the quality of life of the treated patients, with no significant differences between the two groups.

Lumbar Melanoma with Sentinel Lymph Nodes in Multiple Basins - Case Report and Review of the Literature.

Intreduction: Melanoma is an extremely aggressive form of skin neoplasia, an important stage in the diagnostic and treatment is identifying the dissemination at the lymphatic level. For a more accurate staging, the sentinel lymph node biopsy technique is performed, which in most of the time addresses one, respectively 2 locations, but cases with sentinel nodes in 3 lymphatic basins have rarely been described. Case report: We present a case of melanoma located in the right lumbar region, which from the point of view of histopathological features has a Breslow index of 4.2 mm, classified in the pT4b stage. After the CT evaluation was performed, it was decided that there is indication for performing the sentinel lymph node technique and excision with a margin of safety. Scintigraphy revealed that sentinel lymph nodes were identified in 3 different regions, respectively the right axilla and bilateral inguinal. Conclusions: Melanoma located on the trunk can present different lymphatic routes for the sentinel lymph nodes, unlike that on the limbs where certain patterns are present. Identifying these lymph nodes in cases like this involves a challenge both from a diagnostic and surgical point of view.

Targeted axillary dissection reduces residual nodal disease in clinically node- positive breast cancer after neoadjuvant chemotherapy.

BACKGROUND: Any advantage of performing targeted axillary dissection (TAD) compared to sentinel lymph node (SLN) biopsy (SLNB) is under debate in clinically node-positive (cN+) patients diagnosed with breast cancer. Our objective was to assess the feasibility of the removal of the clipped node (RCN) with TAD or without imaging-guided localisation by SLNB to reduce the residual axillary disease in completion axillary lymph node dissection (cALND) in cN+ breast cancer. METHODS: A combined analysis of two prospective cohorts, including 253 patients who underwent SLNB with/without TAD and with/without ALND following NAC, was performed. Finally, 222 patients (cT1-3N1/ycN0M0) with a clipped lymph node that was radiologically visible were analyzed. RESULTS: Overall, the clipped node was successfully identified in 246 patients (97.2%) by imaging. Of 222 patients, the clipped lymph nodes were non-SLNs in 44 patients (19.8%). Of patients in cohort B (n=129) with TAD, the clipped node was successfully removed by preoperative image-guided localisation, or the clipped lymph node was removed as the SLN as detected on preoperative SPECT-CT. Among patients with ypSLN(+) (n=109), no significant difference was found in non-SLN positivity at cALND between patients with TAD and RCN (41.7% vs. 46.9%, p=0.581). In the subgroup with TAD with axillary lymph node dissection (ALND; n=60), however, patients with a lymph node (LN) ratio (LNR) less than 50% and one metastatic LN in the TAD specimen were found to have significantly decreased non-SLN positivity compared to others (27.6% vs. 54.8%, p=0.032, and 22.2% vs. 50%, p=0.046). CONCLUSIONS: TAD by imaging-guided localisation is feasible with excellent identification rates of the clipped node. This approach has also been found to reduce the additional non-SLN positivity rate to encourage omitting ALND in patients with a low metastatic burden undergoing TAD.

[Comparison of the efficacy of gasless robotic surgery through transaxillary apporach and open surgery for papillary thyroid carcinoma].

Objective: To compare the efficacy of gasless robotic surgery through transaxillary approach and open surgery for papillary thyroid carcinoma (PTC). Methods: The data of patient undergoing robotic surgery through transaxillary approach and traditional open surgery for PTC at the Sun Yat-sen Memorial Hospital, Sun Yat-sen University, from November 2016 to June 2023 were retrospectively analyzed. A 1∶1 propensity score matching (PSM) was performed to balance age, sex, extent of surgery, tumor size, capsule invasion, and multifocality. Surgical data, postoperative pathological data, complications, postoperative 2-month visual analog scale (VAS) scores for aesthetics, and follow-up data were compared between the two groups. Results: A total of 728 PTC patients were included. There were 339 patients in the robotic group, among which 262 were female (77.3%) and 77 were male (22.7%), with the age of [M (Q1, Q3)] 39 (32, 46) years and a body mass index (BMI) of 22.8 (20.7, 25.0) kg/m². Meanwhile, 389 patients were in the open group, among which 290 were female (74.6%) and 99 were male (25.4%), with the age of 47 (38, 55) years and a BMI of 23.2 (21.3, 25.5) kg/m2. Further analysis after PSM (there were 264 cases in both groups) showed that in the subtotal thyroidectomy and central neck dissection (LT+CCND) subgroup, the robotic group had longer operative time, higher blood loss, and greater drainage volume compared with the open group [100 (80, 130) min vs 60 (50, 80) min; 10 (10, 20) ml vs 10 (10, 20) ml; 103 (69, 145) ml vs 75 (57, 98) ml; all P<0.001], and the central lymph node metastasis rate was higher in the robotic group [45.6% (57/125) vs 31.8% (47/148), P=0.019]. In the total thyroidectomy and central neck dissection (TT+CCND) subgroup, the robotic group also had longer operative time, higher blood loss, and greater drainage volume compared with the open group [150 (110, 180) min vs 85 (75, 100) min; 20 (10, 20) ml vs 10 (10, 20) ml; 155 (107, 206) ml vs 90 (70, 120) ml; all P<0.001]. The incidence of chest skin numbness at 3 months postoperatively was higher in the robotic group compared with the open group (12.9% vs 0, P<0.001), while there were no statistically significant differences in other postoperative complications (all P>0.05). The VAS score at 2 months postoperatively was higher in the robotic group compared with the open group [9 (9, 9) vs 8 (7, 9), P<0.001]. Three cases of contralateral lobe recurrence occurred in the open group, while there were no case of recurrence in the robotic group. The 5-year overall survival rate was 100.0% in both the robotic and open groups, and there was no statistically significant difference in the 5-year disease-free survival rate between the robotic and open groups (100.0% vs 98.6%, P=0.068). Conclusion: Gasless robotic surgery through transaxillary approach for total thyroidectomy or lobectomy in the treatment of PTC is safe, feasible, and effective, with good cosmetic outcomes and comparable efficacy to traditional surgery.

Endoscopic Bilateral Nipple-sparing Mastectomy via a Single Axillary Incision with Immediate Pre-pectoral Implant-based Breast Reconstruction.

Oncoplastic breast surgery, with its focus on improving cosmetic outcomes while maintaining oncological safety, has fundamentally transformed the landscape of breast cancer surgical treatment, giving rise to an array of techniques for breast reconstruction. Nipple-sparing mastectomy (NSM) with immediate implant-based breast reconstruction (IBBR) has emerged as a cornerstone in managing early breast cancer. Aligned with the principles of minimally invasive surgery, recent years have witnessed the widespread integration of endoscopic approaches in breast surgery, encompassing procedures like endoscopic breast-conserving surgery (E-BCS) and endoscopic nipple-sparing mastectomy (E-NSM), among others. Capitalizing on the advantages of inconspicuous and shorter incisions, improved visibility, and the avoidance of radiation therapy, the popularity of E-NSM with IBBR is on the rise. However, conventional E-NSM with IBBR often requires two or more incisions, which can result in suboptimal cosmetic outcomes and even prosthesis loss.This paper presents a comprehensive account of the intricate surgical procedures involved in endoscopic bilateral nipple-sparing mastectomy with immediate pre-pectoral implant-based breast reconstruction. The insights shared are drawn from the collective experience of our institution. Notable benefits associated with the described surgical approach encompass enhanced cosmetic outcomes, improved postoperative quality of life, and enhanced physiological functions attributable to the application of pre-pectoral implant-based breast reconstruction through a single incision.

The Impact of Obesity on Success of Immediate Lymphatic Reconstruction for Prevention of Breast Cancer-Related Lymphedema.

BACKGROUND: Breast cancer-related lymphedema (BRCL) is a potential sequela of high-risk breast cancer treatment. Preventive treatment with immediate lymphatic reconstruction (ILR) at the time of axillary lymph node dissection (ALND) has emerged as the standard of care; however, there is relatively little known about factors that may contribute to procedural failure. METHODS: A retrospectively maintained, institutional review board-approved study followed patients who underwent ILR at the time of ALND at our tertiary care center between May 2018 and May 2023. Patients who presented for at least one follow-up visit in our multidisciplinary lymphedema clinic met the criteria for inclusion. Patients who developed lymphedema despite ILR and potential contributing factors were further explored. RESULTS: 349 patients underwent ILR at our institution between May 2018 and May 2023. 341 of these patients have presented for follow-up in our multidisciplinary lymphedema clinic. 32 (9.4%) patients developed lymphedema despite ILR. This cohort was significantly more likely to be obese (56% vs 35%, P = 0.04). Multivariate logistic regression demonstrates increased odds of procedural failure in patients with a body mass index (BMI) ≥30 kg/m2 (odds ratio 2.6 [1.2-5.5], P = 0.01). CONCLUSION: These data comment upon our institutions outcomes following ILR. Patients who develop lymphedema despite ILR tend to have a higher BMI, with a significantly increased risk in patients with a BMI of 30 or greater. Consideration of these data is critical for preprocedural counseling and may support a BMI cutoff when considering candidacy for ILR going forward, as well as when optimizing failures for secondary lymphedema procedures.

Prediction of the axillary lymph-node metastatic burden of breast cancer by 18F-FDG PET/CT-based radiomics.

BACKGROUND: The axillary lymph-node metastatic burden is closely associated with treatment decisions and prognosis in breast cancer patients. This study aimed to explore the value of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT)-based radiomics in combination with ultrasound and clinical pathological features for predicting axillary lymph-node metastatic burden in breast cancer. METHODS: A retrospective analysis was conducted and involved 124 patients with pathologically confirmed early-stage breast cancer who had undergone 18F-FDG PET/CT examination. The ultrasound, PET/CT, and clinical pathological features of all patients were analysed, and radiomic features from PET images were extracted to establish a multi-parameter predictive model. RESULTS: The ultrasound lymph-node positivity rate and PET lymph-node positivity rate in the high nodal burden group were significantly higher than those in the low nodal burden group (χ2 = 19.867, p < 0.001; χ2 = 33.025, p < 0.001). There was a statistically significant difference in the PET-based radiomics score (RS) for predicting axillary lymph-node burden between the high and low lymph-node burden groups. (-1.04 ± 0.41 vs. -1.47 ± 0.41, t = -4.775, p < 0.001). The ultrasound lymph-node positivity (US_LNM) (odds ratio [OR] = 3.264, 95% confidence interval [CI] = 1.022-10.423), PET lymph-node positivity (PET_LNM) (OR = 14.242, 95% CI = 2.960-68.524), and RS (OR = 5.244, 95% CI = 3.16-20.896) are all independent factors associated with high lymph-node burden (p < 0.05). The area under the curve (AUC) of the multi-parameter (MultiP) model was 0.895, which was superior to those of US_LNM, PET_LNM, and RS models (AUC = 0.703, 0.814, 0.773, respectively), with statistically significant differences (Z = 2.888, 3.208, 3.804, respectively; p = 0.004, 0.002, < 0.001, respectively). Decision curve analysis indicated that the MultiP model provided a higher net benefit for all patients. CONCLUSION: A MultiP model based on PET-based radiomics was able to effectively predict axillary lymph-node metastatic burden in breast cancer. TRIAL REGISTRATION: This study was registered with ClinicalTrials.gov (registration number: NCT05826197) on May 7, 2023.