Detecting Amyloid Goiter With 99mTc-PYP SPECT/CT in the Setting of Ankylosing Spondylitis: An Uncommon Involvement of AA Amyloidosis.

ABSTRACT: We present a case with systemic amyloidosis secondary to ankylosing spondylitis (AA amyloidosis), whose 99mTc PYP scintigraphy revealed amyloid deposition in the thyroid gland (amyloid goiter). Amyloidosis is characterized by extracellular accumulation of amyloid fibril proteins leading to organ malfunction. Even though AA amyloidosis can be observed in patients with systemic inflammatory diseases, it is a very rare complication in ankylosing spondylitis. SPECT/CT images showed diffuse tracer uptake in enlarged thyroid gland containing fat density areas.

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.

Diagnosis and Evaluation of Treatment Response in Relapsing Polychondritis Using 18F-FDG PET/CT.

A 58-year-old man presenting with dyspnea, weight loss, and night sweating underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) because of a suspicion of malignancy. 18F-FDG PET/CT demonstrated mild to moderate uptake on nasal, cricoid, and tracheobronchial tree cartilages and costovertebral junctions. The diagnosis was relapsing polychondritis, which is a rare multisystem disease characterized by inflammation of cartilage. In addition, subsequent 18F-FDG PET/CT after treatment showed complete metabolic response.

18F-FDG and 68Ga-FAPI-04 PET/CT Findings of a Rare Epithelial-myoepithelial Carcinoma Arising From Ex Pleomorphic Adenoma of Parotid.

Epithelial-myoepithelial carcinoma (EMC) is a rare low-grade salivary gland neoplasm. Distant metastasis is rare, and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has been used to determine the metastatic disease in EMC. 68Ga-fibroblast activation protein inhibitors (FAPI) PET/CT is a promising imaging modality for diagnostic and theognostic purposes in various malignancies. Comparison studies with 18F-FDG have investigated the role of 68Ga-FAPI PET/CT. Herein, we present 18F-FDG and 68Ga-FAPI-04 PET/CT findings of a 51-year-old woman with metastatic EMC arising from ex-pleomorphic adenoma of the parotid.

68Ga-Trivehexin PET/CT: a promising novel tracer for primary hyperparathyroidism.

INTRODUCTION: This study aims to assess 68Ga-Trivehexin PET/CT for detecting hyperfunctioning parathyroid tissue in comparison to [99mTc]Tc-MIBI scintigraphy-SPECT/CT (MIBI scan) in patients with primary hyperparathyroidism (PHPT). METHODS: The cohort comprised 13 patients diagnosed with PHPT based on biochemical analyses, including serum calcium, phosphorus, and parathyroid hormone (PTH) levels. Each participant underwent cervical ultrasonography, MIBI scan, and 68Ga-Trivehexin PET/CT imaging. Complementary 4D-CT and [18F]fluorocholine PET/CT were conducted in 7 patients. Ten lesions of 7 patients underwent PTH wash-out (WO) procedure. 68Ga-Trivehexin PET/CT findings were compared with other modalities and PTH-WO results. RESULTS: Ten patients had sporadic PHPT, while 3 were diagnosed with MEN-1 syndrome-associated PHPT. One patient did not have any identifiable parathyroid lesion across the imaging modalities. On a patient-based analysis, MIBI scan and 68Ga-Trivehexin PET/CT identified parathyroid lesions in 10 and 11 patients, respectively. However, 68Ga-Trivehexin PET/CT detected 7 additional parathyroid lesions that were negative on the MIBI scan. Consequently, 17 lesions were identified and confirmed as hyperfunctioning parathyroid tissue through imaging, PTH-WO, or a combination of both modalities. In lesion-based evaluation, 68Ga-Trivehexin identified 16 lesions compared to 10 by MIBI scan, resulting in a detection rate of 94.1% and 58.8%, respectively. Notably, in three patients who underwent [18F]fluorocholine PET/CT, no lesions were detected; yet 68Ga-Trivehexin PET/CT successfully identified parathyroid lesions in two of these patients. CONCLUSION: Our study provides the first evidence that 68Ga-Trivehexin PET/CT can effectively identify hyperfunctioning parathyroid tissue with a high detection rate warranting further investigations to comprehensively explore its potential in PHPT management.

The Role of [18F]FDG PET/CT in the Characterization of Thymic Epithelial Tumors at Initial Stage.

Purpose: The aim of this study was to evaluate the potential role of [18F]FDG positron emission tomography/computed tomography (PET/CT) in the characterization of thymic epithelial tumors (TETs). Materials and Methods: A total of 73 patients who underwent preoperative [18F]FDG PET/CT were included in this study. Visual total score (VTS), maximum standard uptake values (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and heterogeneity index (HI) parameters were analyzed to investigate the prediction of histopathologic grade and advanced stage. Results: The cohort included 26 patients with low-grade thymoma (LGT), 36 patients with high-grade thymoma (HGT), and 11 patients with thymic carcinoma (TC). Ninety-one percent of TC had VTS >2, whereas 31% of LGT and 75% of HGT had VTS >2. SUVmax, MTV, and TLG were statistically significantly higher in the TC group than in both thymoma and HGT. Using the cutoff value of 7.25 for SUVmax, TC was differentiated from thymomas with 91% sensitivity and 74% specificity. TC had significantly lower HI values than thymomas. HI parameters showed good diagnostic ability to differentiate TC from thymoma and TC from HGT. SUVmax, MTV, and TLG were significantly higher in advanced-stage disease than in early-stage disease. Conclusions: Visual and quantitative parameters can reliably predict both advanced disease and the grade of primary tumor in TETs. Therefore, as a promising metabolic imaging method, [18F]FDG PET/CT makes important contributions to preoperative evaluation in routine clinical practice.

Unusual Metastasis of Signet-Ring Cell Gastric Cancer That Could Not Be Detected With 18 F-FDG PET But With 68 Ga-FAPI PET/CT.

ABSTRACT: A 70-year-old man who was scheduled for surgery because of the recurrence of gastric cancer was referred to our clinic preoperatively. The patient underwent a comprehensive evaluation through 18 F-FDG and 68 Ga-FAPI ( 68 Ga-labeled FAP inhibitors) PET/CT scans. The 68 Ga-FAPI PET/CT scan was particularly valuable in this case because of its ability to detect recurrent mass lesions and identify unusual metastatic sites compared with the 18 F-FDG PET/CT scan.

Combination of 68 Ga-FAPI-04 and Dedicated Breast PET (MAMMI PET) Outperformed Breast MRI and 18 F-FDG PET/CT by Revealing Nipple and Skin Involvement of Breast Cancer.

ABSTRACT: A 41-year-old woman with newly diagnosed breast cancer had suspicious clinical findings of skin involvement on physical examination. The primary tumor had no FDG uptake in 18 F-FDG PET/CT. Nipple and skin had no pathologic enhancement for invasion in breast MRI. Because the T stage was unclear, the patient underwent 68 Ga-FAPI-04 PET/CT for further evaluation. Combination of 68 Ga-FAPI-04 with dedicated breast PET (MAMMI PET) showed nipple and skin involvement of breast cancer with intense FAPI uptake. Consequently, a skin-sparing mastectomy was performed. Histopathological examination confirmed invasive lobular carcinoma infiltration of the deep dermis in the nipple and skin tissue.

Influence of Early Versus Delayed Hepatic Artery Perfusion Scan on 90Y Selective Internal Radiation Therapy Planning.

Purpose: This study evaluated the effect of an increase in the time interval between hepatic intra-arterial injection of 99mTc-macroaggregated albumin (MAA) and hepatic artery perfusion scintigraphy (HAPS) on the lung shunt fraction (LSF) and perfused volume (PV) calculations in the treatment planning of selective internal radiation therapy (SIRT). Methods: The authors enrolled 51 HAPS sessions from 40 patients diagnosed with primary or metastatic liver malignancy. All patients underwent scan at the first and fourth hour after hepatic arterial injection of 99mTc-MAA. Based on single-photon emission computed tomography images, LSF values were measured from each patient's first and fourth hour images. PV1 and PV4 were also calculated based on three-dimensional images using 5% and 10% cutoff threshold values and compared with each other. Results: The authors found that the median of LSF4 was statistically significantly higher than LSF1 (3.05 vs. 4.14, p ≤ 0.01). There was no statistically significant difference between PV1 and PV4 on the 10% (p = 0.72) thresholds. Conclusions: LSF values can be overestimated in case of delayed HAPS, potentially leading to treatment cancellation due to incorrectly high results in patients who could benefit from SIRT. Threshold-based PV values do not significantly change over time; nevertheless, keeping the short interval time would be safer.

Intracoronary electrocardiogram detects coronary microvascular dysfunction and ischemia in patients with no obstructive coronary arteries disease.

BACKGROUND: Coronary microvascular dysfunction (CMD) is the leading cause of ischemia with no obstructive coronary arteries disease (INOCA) disease. Diagnosis of CMD relies on surrogate physiological indices without objective proof of ischemia. OBJECTIVES: Intracoronary electrocardiogram (icECG) derived hyperemic indices may accurately and objectively detect CMD and reversible ischemia in related territory. METHODS: INOCA patients with proven ischemia by myocardial perfusion scan (MPS) and completely normal coronary arteries underwent simultaneous intracoronary electrophysiological (icECG) and physiological (intracoronary Doppler) assessment in all 3 coronary arteries during rest and under adenosine induced hyperemia. RESULTS: Sixty vessels in 21 patients were included in the final analysis. All patients had at least one vessel with abnormal CFR. 41 vessels had CMD (CFR < 2.5), of which 26 had increased microvascular resistance (structural CMD, HMR > 1.9 mmHg.cm-1.s) and 15 vessels had CMD (CFR < 2.5) with normal microvascular resistance (functional CMD, HMR <= 1.9 mmHg.cm-1.s). Only one-third of the patients (n = 7) had impaired CFR < 2.5 in all 3 epicardial arteries. Absolute ST shift between hyperemia and rest (∆ST) has shown the best diagnostic performance for ischemia (cut-off 0.10 mV, sensitivity: 95%, specificity: 72%, accuracy: 80%, AUC: 0.860) outperforming physiological indices (CFR: 0.623 and HMR: 0.653 DeLong's test P = .0002). CONCLUSIONS: In INOCA patients, CMD involves coronary artery territories heterogeneously. icECG can accurately detect CMD causing perfusion abnormalities in patients with INOCA outperforming physiological CMD markers, by demonstrating actual ischemia instead of predicting the likelihood of inducible ischemia based on violated surrogate thresholds of blunted flow reserve or increased minimum microvascular resistance. CONDENSED ABSTRACT: In 21 INOCA patients with coronary microvascular dysfunction (CMD) and myocardial perfusion scan proved ischemia, hyperemic indices of intracoronary electrocardiogram (icECG) have accurately detected vessel-specific CMD and resulting perfusion abnormalities & ischemia, outperforming invasive hemodynamic indices. Absolute ST shift between hyperemia and rest (∆ST) has shown the best classification performance for ischemia in no Obstructive Coronary Arteries (AUC: 0.860) outperforming Doppler derived CMD indices (CFR: 0.623 and HMR: 0.653 DeLong's test P = .0002).icECG can be used to diagnose CMD causing perfusion defects by demonstrating actual reversible ischemia at vessel-level during the initial CAG session, obviating the need for further costly ischemia tests. CLINICALTRIALS: GOV: NCT05471739.

The role of [68 Ga]Ga-FAPI-04 PET/CT in renal cell carcinoma: a preliminary study.

PURPOSE: We aimed to investigate the role of [68 Ga]Ga-FAPI-04 PET/CT and uptake patterns of primary and metastatic lesions in patients with renal cell carcinoma (RCC). METHODS: Twenty patients with a suspicious lesion considered primary renal malignancy or a history of RCC were included in our study. Two patients were excluded from further analyses due to other confirmed malignancies. Six patients were newly diagnosed, while the indication of 12 patients was restaging. All patients underwent [68 Ga]Ga-FAPI-04 and [18F]F-FDG PET/CT. SUVmax and tumor-to-background ratio (TBR) of primary (n = 7) and local recurrent lesions (n = 6) and lymph node (n = 26), lung (n = 32), bone (n = 5), and other metastases (n = 14) were compared between the two tracers. RESULTS: We detected 90 lesions in 18 patients with varying FAPI and FDG uptake values on both PET/CT. The median TBR of FAPI-PET/CT of all lesions was higher than TBR of FDG-PET/CT with statistically significance (5.6 vs. 2.1, p < 0.001). In primary and recurrent lesions, the median SUVmax, TBR, and tumor volume on FAPI-PET/CT were higher than FDG-PET/CT. The median SUVmax of lung lesions on FAPI-PET/CT was statistical significantly higher than FDG-SUVmax (3.8 vs. 1.8, p = 0.02). The median of FAPI-SUVmax on primary lesions was lower in the early stage based on TNM compared to the advanced stage. FAPI-SUVmax in 49% of all lesions were SUVmax ≥ 6, and 13% were SUVmax ≥ 10. In patient-based analyses, seven patients (39%) had at least one lesion with FAPI-SUVmax ≥ 10; 12 patients (67%) had at least one lesion with FAPI-SUVmax ≥ 6. CONCLUSION: This study showed the potential utility of [68 Ga]Ga-FAPI-04 PET/CT showing promising results in RCC. We have presumed that FAPI-PET/CT may be performed for complementary imaging modality providing prognosis and possibility of theranostic application in selected patients.

The inferior performance of [68Ga]Ga-FAPI-04 PET/CT as a diagnostic and theranostic biomarker in [177Lu]Lu-DOTATATE refractory well-differentiated neuroendocrine tumors.

PURPOSE: We aimed to investigate the potential of [68Ga]Ga-FAPI-04 PET/CT as an alternative diagnostic and theranostic tool in well-differentiated NETs refractory to [177Lu]Lu-DOTATATE therapy. METHODS: Patients who received at least two cycles of [177Lu]Lu-DOTATATE therapy for metastatic NETs and progressed under treatment were included. All patients had performed [68Ga]Ga-DOTATATE and [68Ga]Ga-FAPI-04 PET/CT within 3 weeks. The number of PET-positive lesions related to NETs and tumor sites was documented. Mann-Whitney U and chi-square tests were used to compare SUVmax levels of tracers and the number of detected metastases. RESULTS: Twelve patients (7 male, 5 female) who met the eligibility criteria were included in the study. Ten patients had grade 1-2 NET of various origins, and two had paraganglioma and pheochromocytoma. One hundred ninety-eight of 230 lesions (86%) were SSTR positive with a median SUVmax of 16.6 (2.2-76.5), and 88 of 230 lesions (38.2%) were [68Ga]Ga-FAPI-04 positive with a median SUVmax of 5.1 (2.3-21). Median SUVmax level and detected number of tumors were significantly higher in [68Ga]Ga-DOTATATE PET/CT (p=<0.001). [68Ga]Ga-FAPI-04 PET/CT was completely (n:2) or almost completely (n:3) negative in 5 (42%) patients. Two (17%) patients had flip-flop SSTR/FAPI uptake in tumors. In four patients (33%), tumor uptake or the number of PET-positive lesions was inferior in [68Ga]Ga-FAPI-04 PET/CT. In only one patient (8%), tumor uptakes were higher in [68Ga]Ga-FAPI-04 PET/CT. Low-dose [177Lu]Lu-FAPI-46 dosimetry was performed on the FAPI-dominant patient; absorbed radiation doses per GBq were 1.26 Gy, 0.36 Gy, 0.32 Gy, and 0.2 Gy for kidneys, liver, spleen, and total body, respectively. The mean absorbed dose per GBq was 0.33 Gy for liver mass and 0.41 Gy for metastatic lymph nodes. CONCLUSION: Our preliminary results demonstrated that [68Ga]Ga-FAPI-04 PET/CT mainly failed in well-differentiated NETs refractory to [177Lu]Lu-DOTATATE therapy and had a limited role as an alternative diagnostic or theranostic agent. Further investigations with a larger patient population are required to determine the impact of [68Ga]Ga-FAPI-04 PET/CT on NETs.

Isolated Adrenal Metastases of Castration-Resistant Prostate Cancer: Excellent Response to 177 Lu-PSMA With No Adrenal Insufficiency.

ABSTRACT: We present isolated bilateral adrenal metastases successfully treated with 177 Lu-PSMA in a 66-year-old man diagnosed with castration-resistant prostate cancer. The patient had progression under chemotherapy as depicted by 68 Ga-PSMA PET/CT showing intense bilateral PSMA uptake in the adrenal masses, and metastasis-directed therapies were considered as the first option for improving survival because the patient was oligometastatic. However, surgery and radiotherapy were not justifiable options due to the high risk of definitive adrenal insufficiency; therefore, the patient received 4 cycles of 177 Lu-PSMA treatment. 68 Ga-PSMA PET/CT showed near-complete response in bilateral adrenal metastases, and no sign of adrenal insufficiency was observed during follow-up.

An anthropomorphic body phantom for the determination of calibration factor in radionuclide treatment dosimetry.

The aim of this study is to create an inhomogeneous human-like phantom, whose attenuation and scattering effects are similar to the human body, as an alternative to the homogeneous phantoms traditionally used in calibration factor (CF) determination. The phantom was designed to include the thorax, abdomen and upper pelvis regions sized to represent a 75-kg male with a body mass index of 25. Measurements using Lu-177 with 50- and 100-mL lesion volumes were performed using inhomogeneous anthropomorphic body phantom (ABP) and homogeneous NEMA PET body phantom. There was a difference of 5.7% of Calibration Factor including attenuation and scatter effect between ABP and NEMA PET body phantom. Because it better reflects the attenuation and scatter effect, it is recommended to use a human-like inhomogeneous phantom for determination of CF instead of a homogeneous phantom.

Utility of 68 Ga-FAPI-04 PET/CT in Adenoid Cystic Carcinoma Compared With 18 F-FDG PET/CT : Two Case Reports.

ABSTRACT: 68 Ga-fibroblast activation protein inhibitor (FAPI) PET/CT is an emerging imaging modality with high sensitivity and high tumor-to-background ratio in various cancers including in the head and neck regions. The authors present 2 cases of adenoid cystic carcinoma who underwent 68 Ga-FAPI-04 and 18 F-FDG PET/CT. Locoregional recurrence has been detected more precisely in the first case with 68 Ga-FAPI-04. In the second case, 68 Ga-FAPI-04 outperformed 18 F-FDG in the number of lesions and demonstrated intense FAP uptake on widespread metastases, which could provide a treatment option as a theranostic concept. These cases highlight that 68 Ga-FAPI-04 PET/CT may be useful for detecting local recurrence and metastases and help select patients for radionuclide treatments targeting cancer-associated fibroblasts.

FAPI-Negative FDG-Avid Metastatic Relapse of Breast Cancer on PET/CT.

ABSTRACT: A 69-year-old woman with breast cancer underwent 18 F-FDG PET/CT because of the increased CA-15-3 level. 18 F-FDG PET/CT showed multiple hypermetabolic lymph nodes (LNs) in the neck and mediastinum. The patient was also referred for 68 Ga-fibroblast activation protein inhibitor (FAPI) 04 PET/CT for further evaluation. However, 18 F-FDG-avid LNs were FAPI-negative on 68 Ga-FAPI-04 PET/CT. Supraclavicular LN biopsy confirmed the metastasis of breast cancer. Recent reports have focused on the potential of FAPI PET imaging in breast cancer; however, this case highlights that false-negative 68 Ga-FAPI-04-PET/CT findings should also be considered while evaluating metastatic spread.

18F-FDG and 68Ga-FAPI-04 PET/CT in Evaluating Clear-Cell Endometrial Cancer.

ABSTRACT: A 60-year-old woman diagnosed with clear cell endometrial carcinoma received neoadjuvant chemotherapy. However, the patient was inoperable and referred to our clinic to evaluate the extent of the disease. The patient underwent 18FDG PET/CT and 68Ga-FAPI (fibroblast activated protein inhibitor)-04 PET/CT scans. 68Ga-FAPI-04 PET/CT outperformed 18FDG PET/CT demonstrating higher uptake in the metastatic lesions.

SPECT/CT Lymphoscintigraphy Guidance Simplifies and Improves Targeted Axillary Dissection of the Clipped Nodes After Neoadjuvant Chemotherapy in Initially Node-Positive Breast Cancer.

PURPOSE: We assessed the feasibility of SPECT/CT lymphoscintigraphy ( 99m Tc-nanocolloid) method to simplify and improve targeted axillary dissection of clipped axillary lymph node (axLN) after neoadjuvant chemotherapy (NAC) in initially node-positive breast cancer. PATIENTS AND METHODS: Fifteen patients who had clip placement to biopsy-confirmed axLN metastasis due to clinically node-positive breast cancer before NAC and underwent SPECT/CT lymphoscintigraphy for surgery after NAC were included into the study. SPECT/CT lymphoscintigraphy was performed to localize the clipped node and to assess if the clipped lymph node (LN) had 99m Tc-nanocolloid uptake or not. In case the clipped node had no uptake on SPECT/CT, the patient was referred to wire-guided localization procedure. Blue dye was also injected for dual mapping of sentinel LN biopsy. RESULTS: All patients had only ipsilateral axLN metastasis. SPECT/CT lymphoscintigraphy showed that clipped LNs were radioavid in 12 of 15 patients (80%). Clipped LNs were not blue-stained in 5 patients (33.3%), and in 2 of them, clipped LNs were radioavid in SPECT/CT. Wire-guided localization was required in only 3 patients (20%) for nonradioavid/blue-stained clipped LNs. Removal of the clipped nodes was confirmed in all cases with a success rate of 100% by specimen graphy. CONCLUSION: SPECT/CT lymphoscintigraphy seems feasible to determine the clipped LNs intraoperatively without requiring additional invasive methods in most of the patients. This technique simplifies and improves targeted axillary dissection of the clipped axLNs after NAC in initially node-positive breast cancer and can be adapted to clinical practice with further investigations.

Investigation of the probiotic and metabolic potential of Fructobacillus tropaeoli and Apilactobacillus kunkeei from apiaries.

Honeybee products have been among important consumer products throughout history. Microbiota has attracted attention in recent years due to both their probiotic value and industrial potential. Fructophilic lactic acid bacteria (FLAB), whose field of study has been expanding rapidly in the last 20 years, are among the groups that can be isolated from the bee gut. This study aimed to isolate FLAB from the honeybees of two different geographic regions in Turkey and investigate their probiotic, metabolic and anti-quorum sensing (anti-QS) potential. Metabolic properties were investigated based on fructose toleration and acid and diacetyl production while the probiotic properties of the isolates were determined by examining pH, pepsin, pancreatin resistance, antimicrobial susceptibility, and antimicrobial activity. Anti-QS activities were also evaluated with the Chromobacterium violaceum biosensor strain. Two FLAB members were isolated and identified by the 16S rRNA analysis as Fructobacillus tropaeoli and Apilactobacillus kunkeei, which were found to be tolerant to high fructose, low pH, pepsin, pancreatin, and bile salt environments. Both isolates showed anti-QS activity against the C. violaceum biosensor strain and no diacetyl production. The daily supernatants of the isolates inhibited the growth of Enterococcus faecalis ATCC 29212 among the selected pathogens. The isolates were found resistant to kanamycin, streptomycin, erythromycin, and clindamycin. In the evaluation of the probiotic potential of these species, the negative effect of antibiotics and other chemicals to which honeybees are directly or indirectly exposed draws attention within the scope of the "One Health" approach.