About

Dr. Shadfar Bahri is an Associate Professor in the Department of Pharmacology at the University of California, Los Angeles. He received his MD Degree from the University of Goettingen, Germany in 2002. Following his medical degree, he began training in the Department of Radiology in Goettingen before relocating to Irvine, California, where he became an Associate Project Scientist at UC Irvine, Center for Functional Onco-Imaging. Dr. Bahri completed his Internship in General Surgery at UC Irvine in 2014, and subsequently completed his Nuclear Medicine residency at the University of Wisconsin, Madison, before finishing his Nuclear Medicine residency at UCLA. His primary research focus involves prostate cancer imaging, specifically utilizing PSMA tracers, and exploring their application in providing improved treatment options, including theranostic approaches.

Research topics

• Medicine
• Internal medicine
• Urology
• Oncology
• Nuclear medicine
• Surgery
• Pathology
• Radiology

Selected publications

• Impact of postoperative fluorodeoxyglucose positron emission tomography/computed tomography on adjuvant head and neck cancer treatment

  JNCI Cancer Spectrum · 2025-07-01 · 1 citations

  articleOpen access

  BACKGROUND: Residual or recurrent cancer after surgery but prior to adjuvant therapy occurs in a proportion of patients with head and neck cancer and may warrant treatment changes. 18-Fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) may help to identify residual or recurrent disease but is not routinely obtained. We evaluated the relevance of postoperative FDG-PET/CT in this clinical context. METHODS: This single-institution, retrospective study identified patients with head and neck cancer who underwent definitive surgery between January 1, 2013, and April 1, 2023, and received a postoperative FDG-PET/CT prior to adjuvant treatment. We measured the rates of management changes resulting from postoperative FDG-PET/CT findings and the association between having a postoperative FDG-PET/CT which resulted in a management change and oncologic outcomes with selected multivariable competing-risks and proportional hazards regressions. RESULTS: Of 150 patients, 66 (44.0%) had a management change because of the postoperative FDG-PET/CT findings; 62 (93.8%) had radiotherapy plan changes, 20 (30.3%) underwent additional diagnostic testing, 11 (16.7%) had systemic therapy added or changed, 3 (4.6%) underwent reresection, and 15 (10.0%) switched to palliative-intent treatment. Having a postoperative FDG-PET/CT that resulted in a management change was not significantly associated with cancer recurrence or overall survival (both P > .05). CONCLUSIONS: In patients with resected head and neck cancer, postoperative, pre-adjuvant therapy FDG-PET/CT can alter clinical management and may enable additional personalization of treatment. When practical to obtain without delaying treatment, postoperative FDG-PET/CT may have clinical utility though requires careful interpretation due to the risks of false positives.

  PublisherDOI

• Prevention and Management of Peptide Receptor Radionuclide Therapy-Induced Hypertensive Crisis in a Patient With Metastatic Pheochromocytoma

  AACE Endocrinology and Diabetes · 2025-11-17 · 1 citations

  articleOpen accessSenior author

  Background/Objective: While peptide receptor radionuclide therapy (PRRT) with lutetium-177 DOTATATE has been increasingly used for metastatic pheochromocytoma management, PRRT-induced hypertensive crisis has been documented in prior reports. A case is reported here to demonstrate the prevention and management of PRRT-induced hypertensive crisis. Case Report: A 75-year-old male developed PRRT-induced hypertensive crisis. He had known progressive metastatic pheochromocytoma. Despite scheduled daily alpha and beta blockade, he developed symptomatic hypertensive crisis shortly after completion of lutetium-177 DOTATATE infusion in the first 2 treatments, which was managed with as-needed oral alpha blockade. Additional alpha blocker was given right before the initiation of lutetium-177 DOTATATE infusion in the third and fourth treatments. Hypertensive crisis still occurred in the third but not in the fourth treatment. He required the fifth treatment due to tumor progression but he developed another hypertensive crisis despite additional alpha blockade right before treatment. The patient became very concerned for potential hypertensive crisis in the sixth treatment. He was treated with escalating dose of metyrosine for 4 days before the treatment and did not develop hypertensive crisis. No additional alpha blockade was given. Discussion: PRRT may directly stimulate catecholamine release or cause tumor lysis in patients with metastatic pheochromocytoma, resulting in hypertensive crisis. Conclusion: PRRT-induced hypertensive crisis can happen in patients treated for metastatic pheochromocytoma. If hypertensive crisis occurs, caution should be taken on the subsequent treatments. Additional alpha blockade right before lutetium-177 DOTATATE infusion may help; in challenging cases, short-term metyrosine use may prevent PRRT-induced hypertensive crisis.

  PublisherOA PDFDOI

• Swelling of the Right Arm During a Nuclear Medicine Therapy for Metastatic Pheochromocytoma

  AACE Clinical Case Reports · 2024-11-18 · 1 citations

  articleOpen accessSenior author
  PublisherDOI

• FAPI PET uptake patterns after invasive medical interventions: a single center retrospective analysis

  European Journal of Nuclear Medicine and Molecular Imaging · 2024-05-16 · 9 citations

  article
  PublisherDOI

• Malignant Paraganglioma With Calvarial Metastases Presenting With Recurrent Catecholamine-Induced Cardiomyopathy

  AACE Clinical Case Reports · 2024-09-30 · 1 citations

  articleOpen access

  Background/Objective: Cranial metastases rarely occur in malignant paragangliomas (PGLs) or pheochromocytomas, which usually metastasize to the liver, bone, lungs, and lymph nodes. Early detection and intervention with a multidisciplinary approach are crucial given the critical location. Case Report: Our patient was a 31-year-old man diagnosed with periaortic PGL and succinate dehydrogenase subunit B pathogenic variant at the age of 9 years with cardiac arrest. He developed intra-abdominal and skeletal metastatic disease by the age of 14 years and treated with surgery, chemotherapy, and radiation. After being lost to follow-up, the patient presented emergently with headache, palpitations, hypertensive crisis, type 2 non-ST-elevation myocardial infarction, and catecholamine-induced cardiomyopathy, with plasma free metanephrine level of 61.0 pg/mL (0.0-88.0 pg/mL) and elevated serum free normetanephrine level of 662.9 pg/mL (0.0-210.1 pg/mL). Imaging showed a right frontal calvarial lesion, with 4.9-cm intracranial dural and 4.9-cm extracranial components, and a 1.5-cm occipital bone lesion. Following adrenergic blockade, the patient underwent resection of the frontal lesion with pathology showing metastatic PGL. Discussion: A multidisciplinary team was consulted. Because of potential neurotoxicity, radiology advised against radiotherapy. Oncology advised monitoring. Seven months postoperatively, gallium-68 dodecane tetraacetic acid-octreotate positron emission tomography/computed tomography showed no recurrence at the surgical site, stable occipital lesion, and additional skeletal metastases. The patient is planned for peptide receptor radionuclide therapy. Conclusion: Our case highlights the importance of active surveillance in PGL and pheochromocytoma to allow early intervention for metastatic disease and reviews the controversial management of rare calvarial or cerebral metastases, including peptide receptor radionuclide therapy.

  PublisherDOI

• Calculation of the estimated glomerular filtration rate using the 2021 CKD-EPI creatinine equation and whole blood creatinine values measured with Radiometer ABL 827 FLEX

  Clinical Chemistry and Laboratory Medicine (CCLM) · 2022-04-15 · 7 citations

  articleOpen accessSenior author

  Abstract Objectives Estimated glomerular filtration rate (eGFR) can be calculated using serum/plasma creatinine measured with automated chemistry analyzers. It is unclear whether eGFR can be calculated using creatinine values measured in whole blood (WB creatinine). The aim of this study is to determine the comparability between the eGFR calculated using WB creatinine and plasma creatinine. Methods Blood samples from 1,073 patients presented to the emergency department (ED), perioperative areas, intensive care unit (ICU) or nuclear medicine were used to determine the accuracy of WB creatinine. For each sample, WB creatinine was first measured with Radiometer ABL827 FLEX blood gas analyzer, then plasma creatinine was measured with Roche Cobas702 chemistry analyzer after samples were centrifuged. In a subset of 247 samples with the information of age and sex, whole blood eGFR (WB eGFR) and plasma eGFR were calculated using WB creatinine and plasma creatinine and the 2021 chronic kidney disease epidemiology collaboration (CKD-EPI) creatinine equation, respectively. Results WB creatinine correlated with plasma creatinine linearly with a slope of 1.06 and an intercept of −0.01. The coefficient of determination (R 2 ) was 0.99. WB eGFR correlated with plasma eGFR linearly with a slope of 0.95, intercept of −1.63, and R 2 of 0.97. Comparing to plasma eGFR, the sensitivity and specificity for WB eGFR to identify those with high risk (eGFR<30 mL/min/1.73 m 2 ) and low risk (eGFR>45 mL/min/1.73 m 2 ) for kidney injuries was 100 and 92.2%, respectively. The overall concordance in classifying the four stages of kidney damage between WB eGFR and plasma eGFR was 87.9%. Conclusions WB creatinine measured with Radiometer ABL827 Flex can be used to calculate eGFR using the 2021 CKD-EPI creatinine equation. The sensitivity and specificity for WB eGFR to identify those with high and low risks for potential kidney injuries are acceptable in patients needing rapid assessment of their kidney functions.

  PublisherDOI

• Differentiating IDH status in human gliomas using machine learning and multiparametric MR/PET

  Cancer Imaging · 2021-03-10 · 19 citations

  articleOpen access

  BACKGROUND: F]-fluoro-L-phenylalanine (FDOPA) positron emission tomography (PET) images using an unsupervised, two-level clustering approach followed by support vector machine in order to classify the isocitrate dehydrogenase (IDH) status of gliomas. METHODS: Sixty-two treatment-naïve glioma patients who underwent FDOPA PET and MRI were retrospectively included. Contrast enhanced T1-weighted images, T2-weighted images, fluid-attenuated inversion recovery images, apparent diffusion coefficient maps, and relative cerebral blood volume maps, and FDOPA PET images were used for voxel-wise feature extraction. An unsupervised two-level clustering approach, including a self-organizing map followed by the K-means algorithm was used, and each class label was applied to the original images. The logarithmic ratio of labels in each class within tumor regions was applied to a support vector machine to differentiate IDH mutation status. The area under the curve (AUC) of receiver operating characteristic curves, accuracy, and F1-socore were calculated and used as metrics for performance. RESULTS: The associations of multiparametric imaging values in each cluster were successfully visualized. Multiparametric images with 16-class clustering revealed the highest classification performance to differentiate IDH status with the AUC, accuracy, and F1-score of 0.81, 0.76, and 0.76, respectively. CONCLUSIONS: Machine learning using an unsupervised two-level clustering approach followed by a support vector machine classified the IDH mutation status of gliomas, and visualized voxel-wise features from multiparametric MRI and FDOPA PET images. Unsupervised clustered features may improve the understanding of prioritizing multiparametric imaging for classifying IDH status.

  PublisherOA PDFDOI

• Safety of PSMA-Targeted Molecular Radioligand Therapy with ¹⁷⁷Lu-PSMA-617: Results from the Prospective Multicenter Phase 2 Trial RESIST-PC (NCT03042312)

  Journal of Nuclear Medicine · 2021 · 37 citations

  • Medicine
  • Internal medicine
  • Urology

  Lu-PSMA-617 administration schemes (activity levels, time intervals) are needed to optimize tumor dose delivery and treatment efficacy.

  PublisherOA PDFDOI

• Preferential Tumor Localization in Relation to 18F-FDOPA Uptake for Lower-Grade Gliomas

  Research Square · 2021-02-12

  preprintOpen access
  PublisherOA PDFDOI

• 714 An Evaluation of The Discontinuation of Tamsulosin and Finasteride Post Transurethral Resection of The Prostate (TURP) At UHL

  British journal of surgery · 2021-09-01

  article1st authorCorresponding

  Abstract Aim A significant proportion of men suffer from lower urinary tract symptoms (LUTS) secondary to prostatic enlargement. If medical management of BPH fails surgical transurethral resection of the prostate maybe required. The continuation of pharmacological therapy post operatively is redundant, however it was noted that several patients remained on these medications post TURP. The aim of this project was to identify if patients following surgical intervention were discontinued from preexisting medications that became redundant post operatively. Method A retrospective analysis was performed of patients who underwent TURPs between July- December 2019 within the University Hospitals of Leicester NHS trust to assess if patients preexisting medications used for the treatment of LUTS were discontinued post operatively. Results In the above time frame, 104 TURPs were performed in the trust. Out of these, 89 men were already on 5-alpha reductase inhibitors and/or alpha blocker, predominantly tamsulosin and finasteride. Of the 89 men, only 46 were given a clear instruction to stop these drugs on discharge. Conclusions Continuation of the above medication is unnecessary post TURPs with potentially avoidable side effects for patients and an unnecessary expense. A series of changes were implemented to improve practice. These will be reevaluated on the recommencement of TURPs following the covid-19 pandemic.

  PublisherDOI

Frequent coauthors

• Min‐Ying Su

  University of California, Irvine

  33 shared

• Jeon‐Hor Chen

  30 shared

• Chen Jh

  18 shared

• Jérémie Calais

  Molecular Theranostics (United States)

  18 shared

• Johannes Czernin

  16 shared

• Philip M. Carpenter

  13 shared

• Wen‐Pin Chen

  University of California, Irvine

  12 shared

• Aida Kuzucan

  University of California, Irvine

  12 shared