SMARCB1-deficient malignant neoplasm of the pancreas with heterogeneous morphologies that cannot be classified into existing histologic types.

A 50-year-old male with a pancreatic tail tumor underwent distal pancreatectomy. At 14 and 27 months after the primary surgery, metachronous liver metastases were identified and partial hepatectomies were performed for each. Pathologic findings of the primary pancreatic tumor were heterogeneous, but they essentially categorized into two components based on their cytologic features: (i) clear cell component and (ii) epithelioid cell component. The metastatic hepatic tumor was entirely composed of the epithelioid cell component. SMARCB1 expression was lost by immunohistochemistry and heterozygous deletion of SMARCB1 was identified by fluorescence in situ hybridization for both the primary and metastatic tumors. Targeted DNA sequencing of a metastatic hepatic tumor sample was performed and SMARCB1 loss was identified. Based on the morphologic, immunohistochemical, and molecular analyzes, the present case was difficult to classify into any of the existing entities. SMARCB1 deficiency might play a key role in the tumorigenesis.

[False-Positive ¹²³I-Metaiodobenzylguanidine Scan in a Patient with Adrenocortical Cancer].

A 59-year-old woman presented with a left adrenal tumor 4 cm in diameter. The ¹²³I-metaiodobenzylguanidine (MIBG) scintigraphy showed apparent accumulation in the left adrenal tumor. However, the patient had no sign or symptoms suggesting pheochromocytoma. No biochemical evidence of catecholamine excess was noticed. Computed tomography (CT) revealed relatively strong enhancement in the arterial phase, which persisted until the portal phase. The computed tomography (CT) and magnetic resonance imaging showed 2 liver nodule suspected to be metastatic tumors. No ¹²³I-MIBG accumulation was seen in these nodules. CT also showed thyroid nodules with calcification, which suggested papillary thyroid cancer. Based on the findings, open left adrenalectomy, partial hepatectomy and segmentectomy were performed under the clinical diagnosis of pheochromocytoma and metastatic liver tumors. Histopathological diagnosis was adrenocortical cancer. There was only lymphocyte infiltration in the liver nodules. Postoperative recovery was uneventful, and the patient underwent partial thyroidectomy 6 months later. The pathological diagnosis was papillary thyroid cancer. She has been without recurrence or metastases for 18 months after adrenalectomy. We found only 6 cases of MIBG scintigraphy-positive adrenocortical cancer in the literature. The mechanisms for MIBG uptake in adrenocortical cancer are discussed with a review of the literature.

Endoleak detection after endovascular aneurysm repair using unenhanced MRI with flow suppression technique: Feasibility study in comparison with contrast-enhanced CT.

OBJECTIVES: To evaluate the feasibility of unenhanced motion-sensitized-driven equilibrium (MSDE)-prepared balanced turbo field echo (BTFE) sequences for detecting endoleaks after endovascular aneurysm repair (EVAR). METHODS: Forty-six patients treated with EVAR for aortic and/or iliac arterial aneurysms underwent contrast-enhanced CT and MSDE-prepared BTFE sequences with and without flow suppression. Two independent observers reviewed these sequences and their subtraction images and assigned confidence levels for detecting endoleaks. Relative contrast values were calculated by dividing signal intensities by those of paraspinal muscles. CT provided the reference standard. RESULTS: CT showed types I and II endoleaks in one and ten patients, respectively. Areas under receiver operating characteristic curves were 0.92 and 0.97 for observers 1 and 2, respectively. Sensitivity, specificity, accuracy, positive predictive value and negative predictive value of both observers were 91 (10/11), 91(32/35), 91 (42/46), 77 (10/13) and 97 % (32/33), respectively. Relative contrast values of endoleaks and flowing blood significantly decreased by flow suppression on MSDE-prepared BTFE images (P = 0.002 and P < 0.0001 respectively), and were significantly higher than those of the excluded aneurysms on subtraction images (P = 0.003 and P = 0.001, respectively). CONCLUSIONS: Unenhanced MSDE-prepared BTFE sequences are feasible for detecting endoleaks. KEY POINTS: • Flow suppression significantly reduces endoleak signals on MSDE-prepared BTFE images. • Subtraction images of MSDE-prepared BTFE sequences ± flow suppression demonstrate endoleaks. • MSDE-prepared BTFE sequences indicate high diagnostic values (>90 %) except PPV (77 %). • MSDE-prepared BTFE sequences need further refinement to reduce false positives. • Endoleaks can be detected without contrast injection using MSDE-prepared BTFE sequences.

[A Case of Leiomyosarcoma Arising from the Ovarian Vein Preoperatively Diagnosed with Radiological Imaging].

A 54-year-old woman presented withtransient back pain. She was diagnosed withleiomyosarcoma of the inferior vena cava (IVC) by computed tomography (CT) and was referred to our hospital. Contrastenhanced CT revealed a mass (38×42 mm) located in the retroperitoneal space along the course of the right ovarian vein. The mass compressed the IVC into a crescent shape. A tumor thrombus was also found in the IVC. 18 F-fluoro-2-deoxy-D-glucose positron emission tomography (PET) revealed high uptake at the caudal side of the tumor. These radiological findings strongly suggested the diagnosis of leiomyosarcoma arising from the right ovarian vein. She underwent tumor resection with right nephrectomy, IVC resection, and IVC patch reconstruction without any notable events after surgery. Histopathological diagnosis was leiomyosarcoma arising from the ovarian vein, not from the IVC. Two months after the surgery, CT revealed multiple pulmonary metastases and a single liver metastasis. The patient was referred to another hospital for further treatment. She was treated with chemotherapy and was alive with disease at 14 months after the surgery.

Organ Atrophy Induced by Sorafenib and Sunitinib - Quantitative Computed Tomography (CT) Evaluation of the Pancreas, Thyroid Gland and Spleen.

BACKGROUND: To evaluate organ atrophy induced by sorafenib and sunitinib, we retrospectively reviewed the CT scans of renal cell carcinoma (RCC) patients receiving molecular targeted therapy (MTT) using sorafenib or sunitinib, and performed volumetric analysis of the pancreas, thyroid gland, and spleen. MATERIAL/METHODS: Thirteen RCC patients receiving MTT were assigned as the evaluation cases (MTT group), while thirteen additional RCC patients not receiving MTT were retrieved as the Control group. We evaluated the baseline and follow-up CT studies. The volume of the three organs estimated by CT volumetry was compared between the baseline and follow-up CTs. The atrophic ratio of the organ volume in the follow-up CT to that in the baseline CT was calculated, and compared between the MTT and Control groups. RESULTS: All measured organs in the MTT group showed statistically significant volume loss, while no significant change was observed in the Control group. Mean atrophic ratio in the MTT group was 0.74, 0.58, and 0.82 for the pancreas, thyroid and spleen, respectively. The differences in atrophic ratios between both groups were all statistically significant (P<0.05). CONCLUSIONS: Single-agent sorafenib or sunitinib therapy induced statistically significant atrophy in the pancreas, thyroid, and spleen.

Usefulness of MR imaging of the parotid glands in patients with secondary Sjögren's syndrome associated with rheumatoid arthritis.

OBJECTIVE: To assess the correlation between MR imaging (MRI) of parotid glands with X-ray sialography, histopathology of the labial salivary glands, and salivary secretion, in patients with secondary Sjögren's syndrome (SS) associated with rheumatoid arthritis (RA). METHODS: Non-contrast MRI of the parotid glands was performed in 13 secondary SS patients associated with RA who satisfied the revised Japanese diagnostic criteria for SS (1999), and the ACR/EULAR classification criteria for RA (2010). The MRI findings were classified according to the degree of high-intensity signal on T1-weighted images (T1WI) and short inversion time inversion recovery (STIR) images into five grades (0-4), using the modified Nagasaki University grading method. The results of MRI grading were compared with the Rubin and Holt staging of X-ray sialography (0-4), the Greenspan grading of labial salivary gland histopathology (0-4), and salivary secretion by the gum test (ml/10 min). RESULTS: All 13 patients were females, with a mean age of 50.2 ± 11.3 years. According to the MRI grading, 3 patients were Grade 1, 5 were Grade 2, 5 were Grade 3, and none was Grade 0 or Grade 4. The mean stage by X-ray sialography was 1.7 ± 1.0, the mean grade by histopathology was 2.4 ± 1.2, and the mean volume of salivary secretion was 9.7 ± 3.9 ml. The MRI grading correlated significantly with the Rubin and Holt staging and Greenspan grading (P < 0.01 each, Spearman's rank correlation), and significantly and inversely with the results of the gum test (P < 0.05). CONCLUSION: The results suggest that MRI of the parotid glands is a useful noninvasive tool for evaluating destruction and inflammation in the salivary glands.

Noninvasive visualization of endoleaks after endovascular aortic aneurysm repair through unenhanced MRI with motion-sensitized driven equilibrium preparation: Phantom experiments.

PURPOSE: To optimize imaging parameters for balanced turbo field echo (BTFE) sequence combined with motion-sensitized driven equilibrium (MSDE) preparation for endoleak detection and type classification in phantom experiments. MATERIALS AND METHODS: We prepared four phantoms: a pulsatile flow generator with an aortic aneurysm model simulating no endoleak, and a type-1, type-2, and type-3 endoleak. Throughout the experiments, MSDE-BTFE images with and without flow suppression were obtained at 1.5 T and subtraction images were used for image evaluation. The no-endoleak phantom was imaged using different MSDE-BTFE sequences to optimize the k-space trajectory and evaluate the use of electrocardiogram gating. The relative contrast between flowing saline and background was calculated. Then all phantoms were imaged to determine the optimal velocity encoding (VENC) for endoleak detection and type classification. Three independent observers performed the image evaluation. Consistencies between the interpreted and true results were analyzed using kappa statistics. RESULTS: The 3D low-high k-space trajectory with electrocardiogram gating provided the highest relative contrast. Low VENCs of 2-10 cm/s and high VENCs of 20 cm/s showed perfect consistency in endoleaks detection and type classification, respectively. CONCLUSION: MSDE-BTFE sequences of appropriate VENCs has potential for endoleak detection and type classification, without contrast material.

[A case of incidentally diagnosed retroperitoneal lymphangioleiomyomatosis with no respiratory symptoms].

A 39-year-old woman presented with a large retroperitoneal tumor found incidentally in a routine examination. The 138×37×26 mm mass was located in the left paraaortic region. Blood tests and urinalyses including endocrinological examinations revealed no abnormalities. A chest computed tomography revealed multiple thin-walled pulmonary cysts, which is a characteristic of lymphangioleiomyomatosis (LAM). Because the findings strongly suggested that the retroperitoneal tumor was an extrapulmonary manifestion of LAM, we performed laparoscopic resection of the tumor for diagnosis and treatment. The pathological diagnosis was LAM. The tumor cells were immunohistochemically positive for α -smooth muscle actin and weakly positive for HMB45, which is consistent with LAM. The cells were also positive for estrogen receptor (ER) and progesterone receptor (PgR). LAM is a rare progressive disease that affects mainly the lung, and leads to chronic respiratory failure. Extrapulmonary LAM without respiratory symptoms, is extremely rare. In the past, the prognosis of LAM was poor, with a median survival of 8-10 years, but now 85% survive more than 10 years. In the present case, deterioration of pulmonary lesions was not observed during the 10 months follow-up. Because ERand PgRfindings were positive, we will consider hormonal therapy as a treatment option, when the pulmonary lesions progress in the present case.

Prognosis prediction of uterine cervical cancer using changes in the histogram and texture features of apparent diffusion coefficient during definitive chemoradiotherapy.

OBJECTIVES: We investigated prospectively whether, in cervical cancer (CC) treated with concurrent chemoradiotherapy (CCRT), the Apparent diffusion coefficient (ADC) histogram and texture parameters and their change rates during treatment could predict prognosis. METHODS: Fifty-seven CC patients treated with CCRT at our institution were included. They underwent MRI scans up to four times during the treatment course (1st, before treatment [n = 41], 2nd, at the start of image-guided brachytherapy (IGBT) [n = 41], 3rd, in the middle of IGBT [n = 27], 4th, after treatment [n = 53]). The entire tumor was manually set as the volume of interest (VOI) manually in the axial images of the ADC map by two radiologists. A total of 107 image features (morphology features 14, histogram features 18, texture features 75) were extracted from the VOI. The recurrence prediction values of the features and their change rates were evaluated by Receiver operating characteristics (ROC) analysis. The presence or absence of local and distant recurrence within two years was set as an outcome. The intraclass correlation coefficient (ICC) was also calculated. RESULTS: The change rates in kurtosis between the 1st and 3rd, and 1st and 2nd MRIs, and the change rate in grey level co-occurrence matrix_cluster shade between the 2nd and 3rd MRIs showed particularly high predictive powers (area under the ROC curve = 0.785, 0.759, and 0.750, respectively), which exceeded the predictive abilities of the parameters obtained from pre- or post-treatment MRI only. The change rate in kurtosis between the 1st and 2nd MRIs had good reliability (ICC = 0.765). CONCLUSIONS: The change rate in ADC kurtosis between the 1st and 2nd MRIs was the most reliable parameter, enabling us to predict prognosis early in the treatment course.

Diffusion property differences of the lower leg musculature between athletes and non-athletes using 1.5T MRI.

OBJECT: To compare the differences in diffusion properties--namely fractional anisotropy (FA), three eigenvalues of the diffusion tensor (λ1, λ2, and λ3), and apparent diffusion coefficient (ADC)--between athletically-trained and untrained lower leg musculature. MATERIALS AND METHODS: Twelve athletes (Group A) and 11 non-athletes (Group B) were recruited. All were females in their 20s. We scanned diffusion tensor images of both calves and compared FA, the three eigenvalues, and ADC in the gastrocnemius medialis, gastrocnemius lateralis, soleus (SOL), and anterior tibialis muscles between Groups A and B, and between the right and left sides, using two-factor fractional ANOVA. RESULTS: In all muscles of bilateral calves, all three eigenvalues and ADC were lower in Group A than in Group B, with statistically significant differences in all muscles for λ1, λ2, and λ3 and ADC, with a P value of <0.01. Moreover, statistical differences were also found between right and left for λ1, λ2, and λ3 (P < 0.05), and ADC (P < 0.01) of the SOL muscle. FA showed no statistically significant differences in any muscles. CONCLUSIONS: Our results indicate that training causes a decrease of the three eigenvalues and ADC, which we hypothesize is due to an increase of density of myofilaments in the intracellular space, and deformation of the cell induced by enlargement of extracellular components.

Four cases of Trousseau syndrome associated with breast cancer that exhibited central nervous system manifestations.

Cancer-associated thrombosis is known as Trousseau syndrome (TS). Here, we report 4 cases of TS associated with advanced breast cancer that caused central nervous system (CNS) vascular events. All 4 patients experienced sudden onset of CNS symptoms. Imaging revealed multiple brain infarctions or intracranial hemorrhage and all 4 patients had leptomeningeal or brain metastasis. Laboratory findings showed hypercoagulability at diagnosis of TS. Of the 4 patients, 2 patients were treated with unfractionated heparin, while 2 patients could not undergo anticoagulant therapy. In all patients, once the TS occurred, the CNS symptoms progressed rapidly and the prognosis was very poor, 3 patients dying within about a month of diagnosis of TS. Therefore, the predictive factors of TS are important and standards and guidelines for administration of anticoagulants are needed.

Impaired lesion detectability on gadoxetic acid-enhanced MR imaging in indocyanine green excretory defect: case series of three patients.

Indocyanine green (ICG) excretory defect is characterized by an ICG retention rate of more than 50% at 15 min without any other abnormal liver functions. The incidence of ICG excretory defect is 0.007% in the Japanese population. Due to its rarity, the imaging characteristics associated with ICG excretory defect remain unclear. Herein, we present three cases of ICG excretory defect, which showed impaired lesion detectability on gadoxetic acid-enhanced MR imaging (EOB-MRI). In the hepatobiliary phase (HBP) of EOB-MRI, diminished enhancement of the liver parenchyma, prolonged intravascular enhancement, and attenuated gadoxetic acid excretion to the bile duct were observed. Our study also investigated the expression level of organic anion transporting polypeptide (OATP) 1B3 and OATP1B1/1B3, which is related to the uptake of ICG and gadoxetic acid into hepatocytes. All cases showed decreased expression of OATP1B3, which was assumed to be characteristic of ICG excretory defect. The present study indicates that, when patients with ICG excretory defect are evaluated using EOB-MRI, attention should be paid to the impaired lesion detectability in the HBP due to the attenuated gadoxetic acid uptake into the liver parenchyma.

Mass-forming hepatic cryptococcosis: a mimicker of metastatic tumors.

This report provides the first imaging report of isolated intrahepatic cryptococcosis. An 83-year-old man was incidentally pointed out of hepatic nodules. CT revealed four well-defined nodules of 21 mm, 15 mm, 7 mm, and 5 mm in diameter without contrast enhancement. Two nodules displayed central hyperattenuation and the others were totally hyperattenuating. MRI showed that the nodules were hypointense relative to normal liver parenchyma on T1- and T2-weighted images. 18F-FDG PET imaging revealed no obvious increased uptake of nuclear species into the liver nodules. Partial resection of the three largest hepatic nodules was performed based on a preoperative diagnosis of hepatic metastasis from known sigmoid colon cancer. All three resected nodules were composed mainly of necrotic tissue with peripheral histiocytic aggregates and numerous yeast-like cells. The final diagnosis was hepatic cryptococcosis.

Indicator for local recurrence of hepatocellular carcinoma after proton beam therapy: analysis of attenuation difference between the irradiated tumor and liver parenchyma on contrast enhancement CT.

OBJECTIVES: We aimed to identify dynamic CT features that can be used for prediction of local recurrence of hepatocellular carcinoma (HCC) after proton beam therapy (PBT). METHODS: We retrospectively retrieved CT scans of patients with PBT-treated HCC, taken between January 2004 and December 2016. 17 recurrent lesions and 34 non-recurrent lesions were retrieved. The attenuation difference between irradiated tumor and irradiated parenchyma (ADHCC-IP) was compared in the two groups by using the Mann-Whitney U test. Cut-off value of ADHCC-IP was estimated by using the Youden index. RESULTS: The follow-up time after PBT initiation ranged from 374 to 2402 days (median, 1069 days) in recurrent lesions, and 418 to 2923 days (median, 1091.5 days) in non-recurrent lesions (p = 0.892). The time until appearance of local recurrence after PBT initiation ranged from 189 to 2270 days (median, 497 days). ADHCC-IP of recurrent lesions [mean, -21.8 Hounsfield units (HU); from -95 to -31 HU] was significantly greater than that of non-recurrent lesions (mean, -51.7 HU; from -117 to -12 HU) at 1-2 years in portal venous phase (p = 0.039). 5-year local tumor control rates were 0.93 and 0.56 in lesions with ADHCC-IP at 1-2 years in PVP < -55 and ≥ -55 HU, respectively. CONCLUSION: The attenuation difference between irradiated HCC and irradiated liver parenchyma in portal venous phase at 1-2 years after PBT can predict long-term local recurrence of HCC after treatment. ADVANCES IN KNOWLEDGE: We identified a cut-off value for contrast enhancement of HCC after PBT that could predict future local recurrence.

Radiofrequency ablation of the liver: determination of ablative margin at MR imaging with impaired clearance of ferucarbotran--feasibility study.

Institutional review board approval and informed consent were obtained. The feasibility of magnetic resonance (MR) imaging with impaired clearance of ferucarbotran to visualize ablated liver parenchyma surrounding a tumor (ablative margin [AM]) was evaluated after radiofrequency (RF) ablation of the liver. Twenty-one patients with hepatocellular carcinomas underwent RF ablation 2-7 hours after ferucarbotran-enhanced MR imaging. On unenhanced T2*-weighted images acquired after 3-5 days, AMs appeared as hypointense rims. The AM status was related to incidence of residual or recurrent tumors. This technique is feasible for visualization of AM and prediction of residual or recurrent tumors after RF ablation of the liver.

Diffusion-weighted imaging of surgically resected hepatocellular carcinoma: imaging characteristics and relationship among signal intensity, apparent diffusion coefficient, and histopathologic grade.

OBJECTIVE: The objective of our study was to determine the relationship between the signal intensity of hepatocellular carcinoma (HCC) assessed with diffusion-weighted imaging (DWI) and T2-weighted imaging and the apparent diffusion coefficient (ADC) with the histopathologic grade of each nodule. MATERIALS AND METHODS: MR examinations including DWI and T2-weighted imaging of 125 surgically resected hypervascular HCCs in 99 patients were retrospectively reviewed. Pathologic examinations revealed 25 well-, 61 moderately, and 39 poorly differentiated HCCs. Two radiologists reviewed the images and classified the signal intensity of each tumor on DWI and T2-weighted imaging by mutual agreement. The incidence of each signal intensity and the relationship between signal intensity and histopathologic grade were assessed for each sequence. The relationship between the ADC and histopathologic grade was also evaluated. RESULTS: On DWI, 11 of 125 HCCs appeared hypo- to isointense, 27 tumors appeared slightly hyperintense, and the remaining 87 tumors appeared obviously hyperintense to the surrounding liver. Overall, 91.2% (114/125) of HCCs showed hyperintensity to the surrounding hepatic parenchyma. Statistical analysis showed that this rate on DWI was significantly higher than that on T2 turbo spin-echo (TSE) imaging (p < 0.001). On DWI, the tumors tended to show a brighter signal with rising histopathologic grade (p = 0.031), but this trend was not observed on T2-weighted imaging. ADC measurements revealed that the mean ADCs of well-, moderately, and poorly differentiated HCCs were approximately 1.45, 1.46, and 1.36 x 10(-3) mm(2)/s, respectively. There was no significant correlation between ADC and histopathologic grade. CONCLUSION: The histopathologic grade of HCC had no correlation with the ADC, but HCC tumors tended to show a higher signal on DWI as the histopathologic grade rose. However, predicting the correct histopathologic grade of each HCC before surgery on the basis of DWI findings was difficult because of the large overlap among histopathologic grades.

Safety margin of radiofrequency ablation for hepatocellular carcinoma: a prospective study using magnetic resonance imaging with superparamagnetic iron oxide.

PURPOSE: In radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC), it is difficult to assess the ablative margin (AM) precisely by comparing pre- and post-RFA CT images. We prospectively studied the AMs using magnetic resonance imaging (MRI) with pre-administered superparamagnetic iron oxide (SPIO). SPIO is safe for kidney disease patients. MATERIALS AND METHODS: Hepatocellular carcinoma patients were treated with RFA within 8 h of SPIO administration. On T2*-weighted MRI performed 4-7 days later, AM was visualized as a hypointense rim. The ablation status was classified as AM(+) if the rim completely surrounded the tumor, AM(0) if the rim was partly discontinuous without tumor protrusion, and AM(-) if the rim was partly discontinuous with tumor protrusion. The minimal thickness of AM was measured. AM(-) tumors were re-treated consecutively. RESULTS: In total, 85 HCCs ablated in 76 patients were evaluated. The local recurrence rate at 3 years was 2% for AM(+) tumors and 34% for AM(0) tumors (p < 0.01). In addition, no local recurrence was seen in the tumors with an AM of ≥ 2 mm. CONCLUSION: MRI with pre-administered SPIO is useful for determining the AM precisely, and an AM of ≥ 2 mm is recommended for curative RFA. TRIAL REGISTRATION NUMBER: This study was registered with UMIN Clinical Trials Registry (UMIN 000025406).

Phase I/IIa PET imaging study with 89zirconium labeled anti-PSMA minibody for urological malignancies.

OBJECTIVE: We conducted the present phase I/IIa positron emission tomography (PET) imaging study with 89Zr conjugated with desferroxamine-IAB2M (89Zr-Df-IAB2M), an anti-prostate-specific membrane-antigen minibody, to assess its safety and feasibility in patients with urological cancer. METHODS: 89Zr-Df-IAB2M was synthetized by IBA Molecular (Somerset, NJ, USA) and transported by air to Tsukuba Molecular Imaging Center (Tsukuba, Ibaraki, Japan).17 patients received 74 MBq (2 mCi) of 89Zr-Df-IAB2M at total mass doses of 10 mg. Whole-body and plasma clearance, normal-organ and lesion uptake, and radiation absorbed dose were estimated. We also preliminarily tested the performance of 89Zr-immuno-PET imaging for 13 patients with prostate cancer and 4 patients with other urological cancer. RESULTS: The administration of 89Zr-Df-IAB2M was well-tolerated, and no infusion-related reactions were observed in any patient. No adverse events were noted in the laboratory parameters, vital signs, or other parameters. The plasma clearance was biphasic, with an initial rapid phase (t 1/2 fast: 10.1 ± 3.4 h) followed by a slow phase (t 1/2 slow: 49.0 ± 22.7 h). The half-life of radioactivity in the whole body (WB t1/2) was 237 ± 9 h. The highest absorbed radiation dose was 1.67 mGy/MBq, observed in the liver and kidney. The effective dose was 0.68 ± 0.08 mSv/MBq. The radiation dose rate at 0.5 m distance from the patient was 8.67 µSv/h on day 1, and decreased to 2.26 µSv/h at 5 days after injection. Both bone and lymph node metastases were detected with 89Zr-Df-IAB2M by 24 or 48 h imaging. CONCLUSIONS: Administration of 89Zr-Df-IAB2M was well-tolerated and safe in terms of adverse events and radiation exposure and protection. 89Zr-Df-IAB2M is feasible for usage by long-distance transportation. Further studies are warranted for analysis of its use for tumor lesion detection (UMIN000015356).