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Dive into the research topics where Hojjat Ahmadzadehfar is active.

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Featured researches published by Hojjat Ahmadzadehfar.


Hepatology | 2011

Survival after Yttrium-90 resin microsphere radioembolization of hepatocellular carcinoma across Barcelona clinic liver cancer stages: A European evaluation

Bruno Sangro; Livio Carpanese; Roberto Cianni; Rita Golfieri; Daniele Gasparini; Samer Ezziddin; Philipp M. Paprottka; Francesco Fiore; Mark Van Buskirk; José Ignacio Bilbao; Giuseppe Maria Ettorre; Rita Salvatori; Emanuela Giampalma; Onelio Geatti; Kai Wilhelm; Rt Hoffmann; Francesco Izzo; Mercedes Iñarrairaegui; Carlo Ludovico Maini; Carlo Urigo; Alberta Cappelli; Alessandro Vit; Hojjat Ahmadzadehfar; Tobias F. Jakobs; Secondo Lastoria

A multicenter analysis was conducted to evaluate the main prognostic factors driving survival after radioembolization using yttrium‐90–labeled resin microspheres in patients with hepatocellular carcinoma at eight European centers. In total, 325 patients received a median activity of 1.6 GBq between September 2003 and December 2009, predominantly as whole‐liver (45.2%) or right‐lobe (38.5%) infusions. Typically, patients were Child‐Pugh class A (82.5%), had underlying cirrhosis (78.5%), and had good Eastern Cooperative Oncology Group (ECOG) performance status (ECOG 0‐1; 87.7%), but many had multinodular disease (75.9%) invading both lobes (53.1%) and/or portal vein occlusion (13.5% branch; 9.8% main). Over half had advanced Barcelona Clinic Liver Cancer (BCLC) staging (BCLC C, 56.3%) and one‐quarter had intermediate staging (BCLC B, 26.8%). The median overall survival was 12.8 months (95% confidence interval, 10.9‐15.7), which varied significantly by disease stage (BCLC A, 24.4 months [95% CI, 18.6‐38.1 months]; BCLC B, 16.9 months [95% CI, 12.8‐22.8 months]; BCLC C, 10.0 months [95% CI, 7.7‐10.9 months]). Consistent with this finding , survival varied significantly by ECOG status, hepatic function (Child‐Pugh class, ascites, and baseline total bilirubin), tumor burden (number of nodules, alpha‐fetoprotein), and presence of extrahepatic disease. When considered within the framework of BCLC staging, variables reflecting tumor burden and liver function provided additional prognostic information. The most significant independent prognostic factors for survival upon multivariate analysis were ECOG status, tumor burden (nodules >5), international normalized ratio >1.2, and extrahepatic disease. Common adverse events were: fatigue, nausea/vomiting, and abdominal pain. Grade 3 or higher increases in bilirubin were reported in 5.8% of patients. All‐cause mortality was 0.6% and 6.8% at 30 and 90 days, respectively. Conclusion: This analysis provides robust evidence of the survival achieved with radioembolization, including those with advanced disease and few treatment options. (HEPATOLOGY 2011;)


Seminars in Nuclear Medicine | 2010

Radioembolization of Liver Tumors With Yttrium-90 Microspheres

Hojjat Ahmadzadehfar; H.-J. Biersack; Samer Ezziddin

Radioembolization (RE), also termed selective internal radiation therapy (SIRT), has been gradually introduced to the clinical arsenal of cytoreductive modalities in recent years. There is growing evidence for efficiency in liver tumors of various entities, with the most prominent ones being hepatocellular carcinoma, colorectal cancer, and neuroendocrine tumors. Hepatic metastases of numerous other tumor entities including breast cancer, cholangiocarcinoma, and pancreatic cancer are treatment-sensitive, even when being refractory to other treatment modalities such as bland-embolization, regional, or systemic chemotherapy. The antitumor effect of SIRT is related to radiation rather than embolization, with extraordinary high local radiation doses obtained selectively at the site of viable tumor and little affection of the surrounding normal liver tissue. Morphologic changes after RE may pose difficulties for interpretation in conventional restaging with regard to tumor viability and true response to treatment. Therefore, functional imaging, that is, metabolic imaging with (18)F fluorodeoxyglucose positron emission tomography (computed tomography) in the majority of treated tumors, is regarded the gold standard in this respect and should be included for pre- and post-SIRT assessment. To prevent serious toxicity to be associated with the potent antitumor efficacy, meticulous pretreatment evaluation is of particular importance. Improvements in predicting dosimetry will help optimize treatment and patient selection. Nuclear medicine procedures are essential for planning, performing, and monitoring of RE. However, the interdisciplinary aspect of patient management has to be emphasized for this particular treatment form. As SIRT is moving forward from the salvage setting indication to the use in earlier stages of hepatic tumor disease and with the advent of new treatment protocols and targeted therapies, embedding SIRT into a multidisciplinary approach will become even more important. This article focuses on procedural and technical aspects for selection, preparation, and performance of treatment as well as post-therapeutic monitoring and response assessment.


The Journal of Nuclear Medicine | 2017

German Multicenter Study Investigating 177Lu-PSMA-617 Radioligand Therapy in Advanced Prostate Cancer Patients

Kambiz Rahbar; Hojjat Ahmadzadehfar; Clemens Kratochwil; Uwe Haberkorn; Michael Schäfers; Markus Essler; Richard P. Baum; Harshad R. Kulkarni; Matthias Schmidt; Alexander Drzezga; Peter Bartenstein; Andreas Pfestroff; Markus Luster; Ulf Lützen; Marlies Marx; Vikas Prasad; Winfried Brenner; Alexander Heinzel; Felix M. Mottaghy; Juri Ruf; Philipp T. Meyer; Martin Heuschkel; Maria Eveslage; Martin Bögemann; Wolfgang P. Fendler; Bernd J. Krause

177Lu-labeled PSMA-617 is a promising new therapeutic agent for radioligand therapy (RLT) of patients with metastatic castration-resistant prostate cancer (mCRPC). Initiated by the German Society of Nuclear Medicine, a retrospective multicenter data analysis was started in 2015 to evaluate efficacy and safety of 177Lu-PSMA-617 in a large cohort of patients. Methods: One hundred forty-five patients (median age, 73 y; range, 43–88 y) with mCRPC were treated with 177Lu-PSMA-617 in 12 therapy centers between February 2014 and July 2015 with 1–4 therapy cycles and an activity range of 2–8 GBq per cycle. Toxicity was categorized by the common toxicity criteria for adverse events (version 4.0) on the basis of serial blood tests and the attending physician’s report. The primary endpoint for efficacy was biochemical response as defined by a prostate-specific antigen decline ≥ 50% from baseline to at least 2 wk after the start of RLT. Results: A total of 248 therapy cycles were performed in 145 patients. Data for biochemical response in 99 patients as well as data for physician-reported and laboratory-based toxicity in 145 and 121 patients, respectively, were available. The median follow-up was 16 wk (range, 2–30 wk). Nineteen patients died during the observation period. Grade 3–4 hematotoxicity occurred in 18 patients: 10%, 4%, and 3% of the patients experienced anemia, thrombocytopenia, and leukopenia, respectively. Xerostomia occurred in 8%. The overall biochemical response rate was 45% after all therapy cycles, whereas 40% of patients already responded after a single cycle. Elevated alkaline phosphatase and the presence of visceral metastases were negative predictors and the total number of therapy cycles positive predictors of biochemical response. Conclusion: The present retrospective multicenter study of 177Lu-PSMA-617 RLT demonstrates favorable safety and high efficacy exceeding those of other third-line systemic therapies in mCRPC patients. Future phase II/III studies are warranted to elucidate the survival benefit of this new therapy in patients with mCRPC.


The Journal of Nuclear Medicine | 2010

The Significance of 99mTc-MAA SPECT/CT Liver Perfusion Imaging in Treatment Planning for 90Y-Microsphere Selective Internal Radiation Treatment

Hojjat Ahmadzadehfar; Amir Sabet; Kim Biermann; Marianne Muckle; Holger Brockmann; Christiane K. Kuhl; Kai Wilhelm; Hans-Jürgen Biersack; Samer Ezziddin

Selective internal radiation therapy (SIRT), a catheter-based liver-directed modality for treating primary and metastatic liver cancer, requires appropriate planning to maximize its therapeutic response and minimize its side effects. 99mTc-macroaggregated albumin (MAA) scanning should precede the therapy to detect any extrahepatic shunting to the lung or gastrointestinal tract. Our aim was to compare the ability of SPECT/CT with that of planar imaging and SPECT in the detection and localization of extrahepatic 99mTc-MAA accumulation and to evaluate the impact of SPECT/CT on SIRT treatment planning and its added value to angiography in this setting. Methods: Ninety diagnostic hepatic angiograms with 99mTc-MAA were obtained for 76 patients with different types of cancer. All images were reviewed retrospectively for extrahepatic MAA deposition in the following order: planar, non–attenuation-corrected SPECT, and SPECT/CT. Review of angiograms and follow-up of patients with abdominal shunting served as reference standards. Results: Extrahepatic accumulation was detected by planar imaging, SPECT, and SPECT/CT in 12%, 17%, and 42% of examinations, respectively. The sensitivity for detecting extrahepatic shunting with planar imaging, SPECT, and SPECT/CT was 32%, 41%, and 100%, respectively; specificity was 98%, 98%, and 93%, respectively. The respective positive predictive values were 92%, 93%, and 89%, and the respective negative predictive values were 71%, 73%, and 100%. The therapy plan was changed according to the results of planar imaging, SPECT, and SPECT/CT in 7.8%, 8.9%, and 29% of patients, respectively. Conclusion: In pre-SIRT planning, 99mTc-MAA SPECT/CT is valuable for identifying extrahepatic visceral sites at risk for postradioembolization complications.


Oncotarget | 2016

Therapeutic response and side effects of repeated radioligand therapy with 177 Lu-PSMA-DKFZ-617 of castrate-resistant metastatic prostate cancer

Hojjat Ahmadzadehfar; Elisabeth Eppard; Stefan Kürpig; Rolf Fimmers; Anna Yordanova; Carl Diedrich Schlenkhoff; Florian C. Gärtner; Sebastian Rogenhofer; Markus Essler

Prostate-specific membrane antigen (PSMA) is highly expressed on prostate epithelial cells and strongly up-regulated in prostate cancer (PC), making it an optimal target for the treatment of metastasized PC. Radioligand therapy (RLT) with 177Lu-PSMA-DKFZ-617 (Lu-PSMA) is a targeted therapy for metastatic PC. In this study, we retrospectively analyzed the side effects and the response rate of 24 hormone and/or chemorefractory PC patients with a mean age of 75.2 years (range: 64–82) with distant metastases and progressive disease according to the PSA level, who were treated with Lu-PSMA. Median PSA was 522 ng/ml (range: 17–2360). Forty-six cycles of Lu-PSMA were performed. Of the 24 patients, 22 received two cycles. Eight weeks after the first cycle of Lu-PSMA therapy 79.1% experienced a decline in PSA level. Eight weeks after the second cycle of Lu-PSMA therapy 68.2% experienced a decline in PSA relative to the baseline value. Apart from two cases of grade 3 anemia, there was no relevant hemato- or nephrotoxicity (grade 3 or 4). These results confirmed that Lu-PSMA is a safe treatment option for metastatic PC patients and has a low toxicity profile. A positive response to therapy in terms of decline in PSA occurs in about 70% of patients.


The Journal of Nuclear Medicine | 2016

Response and Tolerability of a Single Dose of 177Lu-PSMA-617 in Patients with Metastatic Castration-Resistant Prostate Cancer: A Multicenter Retrospective Analysis

Kambiz Rahbar; Matthias Schmidt; Alexander Heinzel; Elisabeth Eppard; Axel Bode; Anna Yordanova; Michael Claesener; Hojjat Ahmadzadehfar

Radiolabeled prostate-specific membrane antigen (PSMA) ligands represent a true theranostic concept for diagnosis and therapy in patients with relapsed or metastatic prostate cancer. The aim of this study was to evaluate the response to and tolerability of a single dose of 177Lu-PSMA-617 in a large cohort of patients with metastatic castration-resistant prostate cancer (mCRPC). Methods: The data of 82 consecutive patients (median age, 73 y; range, 43–87 y) with mCRPC who received a single dose of 177Lu-PSMA-617 (mean, 5.9 ± 0.5 GBq) were retrospectively analyzed. Data were collected at baseline and 8 wk after therapy. 68Ga-PSMA-11 PET/CT was performed on all patients to verify sufficient PSMA expression. Bone, lymph node, liver, and lung metastases were present in 99%, 65%, 17%, and 11% of the patients, respectively. Tolerability and response were evaluated using hematologic parameters, renal scintigraphy, clinical data, and the prostate-specific antigen (PSA) level at baseline and 8 wk after therapy application. Results: Six patients died, and 2 patients dropped out because they were not willing to continue therapy and follow-up. The complete dataset of 74 patients was available for analysis. Forty-seven patients (64%) showed a PSA decline, including 23 (31%) with a decline by more than 50%. Thirty-five patients (47%) had stable disease: the change in their PSA level ranged from less than a 50% decline to less than a 25% rise. Seventeen patients (23%) had progressive disease: their PSA level rose by more than 25%. There were no significant changes in hemoglobin, white blood cells, creatinine, or tubular extraction rates indicative of toxicity. There was a significant but mild decrease in platelets, but the median value was still within the reference range. Conclusion: This retrospective multicenter analysis suggests that radioligand therapy with 177Lu-PSMA-617 is safe and well tolerated and has a considerable effect on PSA level. Therefore, it offers an additional therapeutic option for patients with mCRPC. These data may justify further prospective randomized studies to evaluate and prove the clinical benefit in terms of survival and quality of life.


The Journal of Nuclear Medicine | 2013

Long-Term Hematotoxicity After Peptide Receptor Radionuclide Therapy with 177Lu-Octreotate

Amir Sabet; Khaled Ezziddin; Ulrich-Frank Pape; Hojjat Ahmadzadehfar; Karin Mayer; Thorsten D Pöppel; Stefan Guhlke; H.-J. Biersack; Samer Ezziddin

Myelosuppression may be the dose-limiting toxicity in peptide receptor radionuclide therapy (PRRT). The aim of this study was to investigate the incidence, severity, and reversibility of long-term hematotoxicity in a large cohort of patient undergoing PRRT with 177Lu-octreotate for metastatic neuroendocrine tumors. The impact of potential risk factors, including initial cytopenia, advanced bone metastatic disease, previous chemotherapy, and cumulative administered activity, and the protective effects of splenectomy were of particular interest. Methods: A total of 632 PRRT courses were performed in 203 patients with metastatic neuroendocrine tumors. A mean activity of 7.9 GBq of 177Lu-octreotate was administered per treatment cycle, with a goal of 4 courses at standard intervals of 3 mo. Hematologic parameters were determined before each treatment course, at 2- to 4-wk intervals between the courses, 8–12 wk after the last course of PRRT, and at 3-month intervals for further follow-up. Toxicity was recorded with Common Terminology Criteria for Adverse Events (version 3.0). Results: Myelodysplastic syndrome as a delayed adverse event was documented in 3 patients (1.4%). Relevant but reversible hematotoxicity (grade 3 or 4) occurred in 23 patients (11.3%) and 29 administrations (4.6%), with leukopenia in 2.7% and thrombocytopenia in 1.7%. The mean time to blood count recovery was 12 mo after the termination of PRRT (range, 3–22 mo). The only preexisting factor that contributed to hematotoxicity was initial cytopenia (P < 0.001). A high level of cumulative administered activity (>29.6 GBq) was associated with relevant leukopenia (P < 0.001). None of the patients with a history of splenectomy developed grade 3 or 4 hematotoxicity, and splenectomy was inversely associated with the incidence and degree of leukopenia (P = 0.02) and thrombocytopenia (P = 0.03) Conclusion: PRRT-induced myelosuppression is almost invariably reversible and rarely requires clinical measures. Administered activity and initial cytopenia are the only factors contributing to myelosuppression, whereas splenectomy may exert a protective effect.


The Journal of Nuclear Medicine | 2014

Predictors of Long-Term Outcome in Patients with Well-Differentiated Gastroenteropancreatic Neuroendocrine Tumors After Peptide Receptor Radionuclide Therapy with 177Lu-Octreotate

Samer Ezziddin; Mared Attassi; Charlotte Yong-Hing; Hojjat Ahmadzadehfar; W Willinek; Frank Grünwald; Stefan Guhlke; H.-J. Biersack; Amir Sabet

Outcome analyses for patients with gastroenteropancreatic neuroendocrine tumors (GEP NET) after peptide receptor radionuclide therapy (PRRT) are still limited, especially with regard to the impact of the Ki-67 index. Using a single-center analysis, we aimed to establish predictors of survival. Methods: We retrospectively analyzed a consecutive cohort of 74 patients who had metastatic GEP NET and underwent PRRT with 177Lu-octreotate (mean activity of 7.9 GBq per cycle, aimed at 4 treatment cycles at standard intervals of 3 mo). Patients (33 with pancreatic NET and 41 with nonpancreatic GEP NET) had unresectable metastatic disease graded as G1 or G2 (G1/G2) and documented morphologic or clinical progression within less than 12 mo or uncontrolled disease under somatostatin analog treatment. Responses were evaluated according to modified Southwest Oncology Group criteria. Potential predictors of survival were analyzed with the Kaplan–Meier curve method (log-rank test) and multivariate analysis (P < 0.05). Results: The response rates were 36.5% partial response, 17.6% minor response, 35.1% stable disease, and 10.8% progressive disease for the entire cohort; 54.5% partial response, 18.2% minor response, 18.2% stable disease, and 9.1% progressive disease for pancreatic NET; and 22.0% partial response, 17.1% minor response, 48.8% stable disease, and 12.2% progressive disease for nonpancreatic GEP NET. The median progression-free survival and overall survival were 26 mo (95% confidence interval, 18.3–33.7) and 55 mo (95% confidence interval, 48.8–61.2), respectively. Besides the Ki-67 index, a Karnofsky performance score of less than or equal to 70%, a hepatic tumor burden of greater than or equal to 25%, and a baseline plasma level of neuron-specific enolase of greater than 15 ng/mL independently predicted shorter overall survival (hazard ratio, 2.1–3.1). Patients with a Ki-67 index of greater than 10% still had median progression-free survival and overall survival of 19 and 34 mo, respectively. Conclusion: The results of this study demonstrated the favorable response and long-term outcome of patients with G1/G2 GEP NET after PRRT. Independent predictors of survival were the Ki-67 index, the patient’s performance status (Karnofsky performance scale score), the tumor burden, and the baseline neuron-specific enolase level. Even patients with a Ki-67 index of greater than 10% seemed to benefit from PRRT, with a good response and a notable long-term outcome. We present the first evidence, to our knowledge, that even in patients with metastatic disease the distinction between G1 and G2—in particular, between G1 (Ki-67 index of 1%–2%) and low-range G2 (Ki-67 index of 3%–10%)—provides prognostic stratification.


Journal of Hepatology | 2013

Comparison of the survival and tolerability of radioembolization in elderly vs. younger patients with unresectable hepatocellular carcinoma

Rita Golfieri; José Ignacio Bilbao; Livio Carpanese; Roberto Cianni; Daniele Gasparini; Samer Ezziddin; Philipp M. Paprottka; Francesco Fiore; Alberta Cappelli; Macarena Rodriguez; Giuseppe Maria Ettorre; Adelchi Saltarelli; Onelio Geatti; Hojjat Ahmadzadehfar; Alexander Haug; Francesco Izzo; Emanuela Giampalma; Bruno Sangro; Giuseppe Pizzi; Ermanno Notarianni; Alessandro Vit; Kai Wilhelm; Tobias F. Jakobs; Secondo Lastoria

BACKGROUND & AIMS The European Network on Radioembolization with Yttrium-90 resin microspheres study group (ENRY) conducted a retrospective study to evaluate the outcomes among elderly (≥ 70 years) and younger patients (<70 years) with unresectable hepatocellular carcinoma (HCC) who received radioembolization at 8 European centers. METHODS Patients with confirmed diagnosis of unresectable HCC who either progressed following resection or locoregional treatment and/or who were considered poor candidates for chemoembolization were evaluated by a multidisciplinary team for radioembolization with (90)Y-resin microspheres (SIR-Spheres; Sirtex Medical). The survival outcome and all adverse events were compared between the two age groups. RESULTS Between 2003 and 2009, 128 elderly and 197 younger patients received radioembolization. Patients in both groups had similar demographic characteristics. Many elderly and younger patients alike had multinodular, BCLC stage C disease, invading both lobes (p = 0.648). Elderly patients had a lower tumor burden, a smaller median target liver volume (p = 0.016) and appeared more likely to receive segmental treatment (p = 0.054). Radioembolization was equally well tolerated in both cohorts and common procedure-related adverse events were predominantly grade 1-2 and of short duration. No significant differences in survival between the groups were found (p = 0.942) with similar median survival in patients with early, intermediate or advanced BCLC stage disease. CONCLUSIONS Radioembolization appears to be as well-tolerated and effective for the elderly as it is for younger patients with unresectable HCC. Age alone should not be a discriminating factor for the management of HCC patients.


Melanoma Research | 2008

Preoperative 18F-FDG-PET/CT imaging and sentinel node biopsy in the detection of regional lymph node metastases in malignant melanoma.

Baljinder Singh; Samer Ezziddin; Holger Palmedo; Michael Reinhardt; Holger Strunk; Thomas Tüting; Hans-Jürgen Biersack; Hojjat Ahmadzadehfar

The objective of this study was to evaluate the role of preoperative 18F-fluorodeoxyglucose-positron emission tomography/computed tomography scanning, preoperative lymphoscintigraphy (LS), and sentinel lymph node biopsy in patients with malignant melanoma. Fifty-two patients (36 men: 16 women; mean age 55.0±13.0 years; median age 61 years; range 17–76 years) with malignant melanoma were selected. According to the latest version of the American Joint Committee on Cancer staging system, the disease in the study patients was initially classified as either stage I or II. The other primary tumor characteristics were mean Breslow depth=2.87 mm and median=2 mm; range 1–12.0 mm and Clarks levels III–V. None of the study patients had clinical or radiological evidence of regional lymph node metastatic disease. At least one sentinel node was identified in all patients. Preoperative LS detected a total of 111 sentinel lymph nodes (average 2.13 sentinel lymph node per patient) and demonstrated a single nodal draining basin in 38 (73%) patients and multiple (2–3 draining basins) in the remaining 14 (27%) patients. Fourteen out of the 52 patients (27%) had at least one involved sentinel node. Positron emission tomography was true positive in two patients with a sentinel node greater than 1 cm and false positive in two other patients. In this study, the detection of sentinel lymph node by LS and gamma probe had a sensitivity of 100%. In contrast, 18F-FDG-PET imaging demonstrated very low sensitivity (14.3%; 95% CI, 2.5 to 44%) and positive predictive value (50%; 95% CI, 9 to 90%) for localizing the subclinical nodal metastases. The specificity, net present value, and diagnostic accuracy were 94.7, 75, and 73%, respectively. Preoperative fluorodeoxyglucose-positron emission tomography/computed tomography imaging is not able to substitute LS/sentinel lymph node biopsy in patients at stage I or II.

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Markus Essler

University Hospital Bonn

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Amir Sabet

University Hospital Bonn

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Anna Yordanova

University Hospital Bonn

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H.-J. Biersack

University Hospital Bonn

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