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To evaluate the feasibility and diagnostic performance of 18F-FDG PET/CT-guided biopsy of abdominal and pelvic lesions with automated robotic arm (ARA) assistance. This prospective study included 114 patients (75 men, 39 women; mean age 51.3 ± 14.7 years, range: 18–90 years) who underwent PET/CT-guided biopsy of FDG-avid abdominal and pelvic lesions from October 2014 to December 2017. Of these patients, 54 had a prior inconclusive CT-guided biopsy. The biopsies were done with ARA assistance, and a real-time sample was obtained after confirming the position of the needle tip within the target lesion on PET/CT. Histopathology reports were reviewed to evaluate the diagnostic performance of the procedure. Clinical or imaging follow-up was done to confirm negative results. The lesions were successfully targeted in 110 of the 114 patients (96.5%) and yielded a pathological diagnosis. Pathological diagnoses were confirmed in 50 of the 54 patients with a prior inconclusive biopsy. Of the 110 lesions, 82 were malignant, 20 were benign, and 8 showed minimal residual FDG uptake at the end of treatment and had no active disease even on clinical and imaging follow-up of at least 3 months. Findings were true-positive in 102 lesions, false-positive in none, true-negative in eight and false-negative in four. The procedure showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 96.2%, 100%, 100%, 66.7 and 96.5%, respectively. No immediate complications or delayed life-threatening events were observed. Percutaneous biopsy of metabolically active abdominal and pelvic lesions with ARA assistance is a technically feasible, safe and accurate method for pathological diagnosis with high diagnostic performance. PET-guided biopsy is highly practical and useful in patients, especially in those with a previous inconclusive biopsy.

We present a case of papillary thyroid cancer (post-thyroidectomy status) on regular treatment with suppressive Levothyroxine therapy. On follow-up at 6 months after radioactive iodine ablation for remnant thyroid tissue, her thyroglobulin, and anti-thyroglobulin levels were 0.06 ng/ml and 670 IU/ml, respectively. Low-dose whole-body I-131 scan was negative. To look for the cause of isolated increased anti-thyroglobulin level, a whole-body (18)F-FDG PET/CT was done which revealed multiple FDG-avid lytic skeletal lesions suggestive of metastases. For confirmation of diagnosis, (18)F-FDG PET/CT-guided metabolic biopsy was done, which revealed Langerhans’ cell histiocytosis on histopathological examination.

Introduction: Systemic Sclerosis is known to involve the gastrointestinal system and can lead to multitude of problems predominantly affecting the GI motility. Methods: It was a prospective, observational, single centre study of fifty consecutive patients with SSc who presented to rheumatology clinic. Gut score was assessed using UCLA SCTC GIT 2.0 questionnaire. 35 patients underwent esophago- gastro duodenoscopy(UGIE), 31 underwent esophageal manometry, 37 underwent lactulose breath test to assess orocaecal transit time (OCTT) and glucose breath test for detecting small intestinal bacterial overgrowth (SIBO) and 36 underwent gastric emptying scintigraphy to measure gastric emptying time. Results: GI involvement was seen in 98% of patients, with most common symptom being regurgitation (78%).Mean T score of the GUT score was 0.60±0.27. In UGIE, esophagitis was seen in 30, of which 3 had candidiasis and 1 had HSV esophagitis. Hiatus hernia was noted in 10 patients. Mean lower esophageal sphincter pressure was 16.1± 12.7 mmHg with hypotensive sphincture in twelve patients. Esophageal peristaltic abnormalities were observed in 28(90%) patients. Gastric emptying was delayed in10/36 patients. OCTT was prolonged in 23/ 37 patients whereas SIBO was noted in 7/37. Conclusion: GI involvement is common in SSc with esophagus being most commonly affected. Motility abnormalities make them prone for super added infections especially infectious esophagitis and SIBO and should be investigated for early detection and treatment.

Herpes zoster virus reactivation in the lumbosacral dermatomal distribution is an unusual site of manifestation and atypical in presentation than its usual sites in thoracolumbar (D3–L2) and facial (V1) dermatomes. Here, we are reporting a patient of marginal zone lymphoma who on fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography scan performed for chemotherapy response evaluation showed hypermetabolic cutaneous and subcutaneous lesions in the right vulva and posteromedial aspect of the right thigh along with ipsilateral pelvic lymph nodes involvement as an incidental finding. Subsequently, FDG active lesions were considered to be as herpes zoster virus reactivation rather than the recurrence of lymphoma and treated with antiviral drug.

Immunoglobulin G4 (IgG4)-related disease is known to mimic multiple malignancies and always poses a diagnostic challenge. We report a case of a 20-year-old young man, who presented with unexplained recurrent episodes of fever and pain abdomen. F-FDG PET/CT revealed intense focal FDG avidity in the prostate. On further workup, he had an elevated serum IgG4 level, and a clinical diagnosis of immunoglobulin G4-related disease was kept. A follow-up FDG PET/CT after glucocorticoid therapy revealed resolution of FDG avidity in the prostate with fall in serum IgG4 levels, hence confirming a diagnosis of atypical immunoglobulin G4-related disease involving isolated prostate gland.

Persistent hyperinsulinemic hypoglycemia in adults is most commonly caused by insulinomas, which pose a diagnostic challenge to physicians, surgeons, and radiologists and require multimodality imaging for precise localization and staging. PET tracers such as F-FDOPA and glucagon-like peptide 1 receptor analogs have been used for imaging insulinomas. Glucagon-like peptide 1 receptor analogs have recently shown promising results in preoperative localization of these tumors, as all insulinomas express glucagon-like peptide 1 receptors. Ga-DOTA-Exendin PET and MRI done in the present case helped in precise localization and management of the culprit lesion, whereas contrast-enhanced CT and F-FDOPA PET failed to do so.

This paper reports the gas sensing properties of CdGa2O4 spinel oxide-based gas sensors for formaldehyde. CdGa2O4-based nanomaterials were prepared by co-precipitation method followed by calcination at different temperatures for 4 h. The structure, morphology and elemental compositions of the materials were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). The effects of precipitation pH value and calcination temperature on gas sensing properties of the obtained materials were investigated. The results showed that the materials prepared under different conditions exhibited good responses to 1 ppm formaldehyde. In addition, the material obtained at co-precipitation pH = 9.00 and calcination at 700 °C for 4 h showed responses of 7.22 and 1.21 to 1 and 0.01 ppm formaldehyde, respectively; the corresponding response-recovery times were 9.6–10.9 s and 5.0−4.3 s, respectively. The results demonstrated that CdGa2O4 is a promising candidate for the detection of formaldehyde at ultralow concentrations.

Localizing the sites of infection in the body is possible in nuclear medicine using a variety of radiopharmaceuticals that target different components of the infective and inflammatory cascade. Gamma(γ)-emitting agents such as [67Ga]gallium citrate were among the first tracers used, followed by development of positron-emitting tracers like 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG). Though these tracers are quite sensitive, they have limited specificity for infection due to their concentration in sites of non-infective inflammation. White blood cells (WBC) labelled with γ or positron emitters have higher accuracy for differentiating the infective processes from the non-infective conditions that may show positivity with tracers such as 18F-FDG. We present a pictorial review of potential clinical applications of PET/CT using 18F-FDG labelled WBC.

Our rationale was to evaluate the role of 99mTc-methylene diphosphonate (99mTc-MDP) SPECT/CT for the detection of sacroiliitis in spondyloarthropathies by comparing it with clinical markers and MRI findings. Methods: We prospectively included 155 patients (83 men and 72 women; mean age, 35.80 ± 12.40 y; range, 18–60 y) diagnosed with spondyloarthropathies as per the criteria of the European Spondyloarthropathy Study Group. All patients underwent clinical evaluation (using the Bath ankylosing spondylitis disease activity index [BASDAI]), measurement of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level, planar 99mTc-MDP bone scintigraphy, SPECT/CT, and MRI of the pelvic region. Using MRI as the reference criterion, the diagnostic accuracy of the clinical and scintigraphic parameters was assessed. On planar bone scintigraphy and SPECT, a score of 0, 1, or 2 was assigned when tracer uptake in the sacroiliac joint was less than, equal to, or more than that in the sacrum. A score of 2 was considered positive for the diagnosis of sacroiliitis. Results: The sensitivity, specificity, accuracy, and positive and negative predictive values of 99mTc-MDP SPECT/CT were 90.0%, 80.0%, 87.0%, 92.0%, and 75.0%, respectively. The accuracy of SPECT/CT (87%) was better than that of ESR (58.1%), CRP (32.9%), BASDAI scoring (77%), and planar bone scintigraphy (53%). Similar results were found for sensitivity and negative predictive value. Regarding specificity, SPECT/CT (80%) was lower than BASDAI scoring (88.6%) and equal to planar bone scintigraphy (80%). Regarding positive predictive value, SPECT/CT (92%) was a bit lower than BASDAI scoring (93.6%). κ-values for planar 99mTc-MDP bone scanning and SPECT/CT were 0.167 and 0.673, respectively, indicating poor agreement for planar bone scanning and good agreement for SPECT/CT. A significant (P

To compare thyroid hormone levels between septicemic preterm neonates with and without shock.Preterm septicemic infants with shock constituted Group A (n=36) and those without shock constituted Group B, with groups matched (1:1) for gestation and postnatal age. Those with maternal thyroid disorders, thyrotropic medication and life expectancy12 hours were excluded. We compared serum tri-iodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) between the groups by univariate and multivariate (adjusting for SNAPPE-II) analysis.Median (IQR) TSH was significantly lower in Group A [1.39 (0.83,3.48)] vs Group B [5.1 (2.32,7.19)] mmol/dL (P0.001). Serum T3 and T4 were also lower in Group A (P0.001). On multivariate analysis, none of these measures were independently associated with septic shock.Thyroid hormone levels do not independently predict presence of shock among septic preterms.

Background Most adults with ectopic thyroid gland (ETG) are asymptomatic at the time of detection of ETG. Unlike adults, the clinical and morphological spectrum of ETG in children remains less characterized. Methods We retrospectively analyzed data of children with primary congenital hypothyroidism (CH) due to ETG who attended the pediatric endocrinology clinic of our hospital between April 2004 and March 2016. The diagnosis of ETG was based on combined scanning with technetium-99m (99mTc) pertechnetate thyroid scintigraphy and high-resolution thyroid ultrasonography. Results Twenty-four (18.7%) of the 128 children with primary CH were identified to have ETG. Their mean age at diagnosis was 64.3 ± 47 months (range, 0.5–144 months); 17 (70.8%) were girls. The mode of diagnosis was based on symptoms in 20, newborn screening in 3 and incidental in 1. Symptoms included poor weight gain in 13 (54%) developmental delay in 9 (37.5%), constipation in 8 (33%), decreased activity in 6, excessive sleepiness in 5, anorexia in 1 and decreased sweating in 1. The anatomical location of ETG was lingual in 17 (71%) and sublingual in 5 (21%). Thyroid function tests showed overt hypothyroidism in 16 and subclinical in 8. The mean duration of follow up was 16 ± 27.5 months (range 0.5–114 months). Conclusion We found symptomatic hypothyroidism to be common at presentation in our children with ETG. This is the largest series of children with ETG based on the diagnosis by combined scanning.

We report a 62-year-old woman who presented with chronic watery diarrhea and weight loss. During evaluation, she was found to have pneumobilia in the absence of gallstones, raising the suspicion of bilioenteric communication. Computed tomography demonstrated adherence of the gallbladder to the adjacent transverse colon. Hepatobiliary scintigraphy demonstrated the presence of a cholecystocolic fistula. A planned uneventful open cholecystectomy with resection of fistulous tract and closure of colonic opening was performed, resulting in the complete resolution of clinical symptoms.

Neoplasms arising from the urachus are extremely rare. We present a case of a young woman with mild abdominal pain and a palpable swelling in the mid abdomen with incidental detection of a subumbilical mass. Repeated fine-needle aspiration cytology failed to reveal the true nature of the lesion. F-FDG PET/CT showed tracer uptake in the cranial end of urachal remnant lesion. Core biopsy from the site with maximal FDG uptake turned out to be lymphomatous involvement in urachus, which is extremely rare and previously unreported.

Malignant melanoma is a highly aggressive tumor and surgical resection is the primary treatment. However, the chances of recurrence are quite high despite complete resection. The aim of study was to evaluate the 18F-fluorodeoxyglucose(18F-FDG) positron emission tomography–computed tomography (PET/CT) in detection of recurrent melanoma after curative surgery and its prognostic value. Fifty-four melanoma patients (32 women) with prior primary lesion resection were evaluated with 18F-FDG PET/CT for clinically suspicious recurrent disease. The diagnostic accuracy of 18F-FDG PET/CT (visual interpretation as well as semi-quantitative parameter) was determined on the basis of subsequent imaging and clinical follow-up. Melanoma-specific survival and risk of progression (hazard ratio [HR]) were assessed using Kaplan–Meier method and Cox regression analysis. 18F-FDG PET/CT detected recurrent diseases in 36 (66%) patients including distant metastases in 13 patients and second synchronous malignancy in 2 patients. Overall, the sensitivity, specificity, positive predictive value, and negative predictive value of 18F-FDG PET/CT were 91.2%, 80.0%, 88.6%, and 84.2%, respectively, with area under the curve of 0.86 (95% confidence interval: 0.74–0.97; P < 0.05). Positive 18F-FDG PET/CT study was associated with a significantly shorter overall survival than negative study (30.8 ± 4.6 vs. 64.5 ± 6.9 months, P < 0.05). Apart from positive 18F-FDG PET/CT scan, maximum standardized uptake value (SUVmax) >2.7 and combination of both were independently associated with an increased risk of disease progression (HR = 7.72, 21.58, and 11.37, respectively; P < 0.05). 18F-FDG PET/CT showed enhanced diagnostic performance in patients with suspicious recurrent malignant melanoma leading to appropriate management. FDG positivity along with SUVmax >2.7 provides important prognostic value in predicting the survival outcomes and assessing the risk of disease progression.

Infection of aortic valve-tube graft, although rare, is associated with high morbidity and mortality. Early identification of site and extent of infection is not only challenging but also crucial for adequate patient management and prognostication of disease. Combined clinical, laboratory investigation and imaging modalities assist in the identification of aortic valve graft infection. Molecular imaging techniques like PET/CT using F-FDG and F-FDG-labeled autologous leukocytes (LALs) have improved the sensitivity for detection of infection, resulting in better outcome for these patients. F-FDG-labeled autologous leukocyte PET/CT in our patient after Bentall procedure accurately localized the site and extent of infection.

F-Fluorocholine is a relatively new, extremely versatile radiotracer for detecting proliferative or mitogenic activity. Its diagnostic potential has been explored in cancers of the prostate, liver, esophagus, breast, brain, and lung, as well as lymphoma, sarcoma, melanoma, and parathyroid adenomas. The authors present a case where fluorocholine PET/CT performed for characterizing a space-occupying lesion in the brain revealed intensely tracer-avid skull lesions with intracranial soft tissue component and multiple other skeletal lesions. Fine-needle aspiration cytology from the skull and chest wall lesions confirmed the diagnosis of plasma cell neoplasm.

Purpose of the Study: Radioiodine (I-131) is used as an effective noninvasive treatment for thyroid malignancies. Salivary gland is one of the most affected nontarget organs. The present study aims to perform early quantification of salivary gland function after I-131 therapy (RIT) for thyroid cancer considering I-131 down-scatter in the Tc-99m window. Materials and Methods: A total of 20 patients (6 males and 14 females) with differentiated thyroid carcinoma were enrolled in the study. Baseline dynamic salivary scintigraphy was performed in all patients using 185–370 MBq (5–10 mCi) Tc-99m pertechnetate. Posttherapy, salivary scintigraphy was performed 10–25 days after RIT in the range of 1.85–7.4 GBq (50–200 mCi). Time–activity curves obtained from the pre- and posttherapy dynamic salivary scintigraphy were used for semi-quantitative analysis. Uptake ratio (UR), ejection fraction (EF%), and maximum accumulation (MA%) were calculated by drawing regions of interest of individual parotid and submandibular glands over a composite image, after correcting for down-scatter from I-131 in the Tc-99m window. A paired t-test was used for comparison of the parameters obtained. Results: Significant changes were observed in UR and EF% of both parotid and submandibular glands (P < 0.05). No significant changes were found in the value of MA% of left parotid gland and both submandibular glands in the posttherapy scans in comparison to pretherapy scans (P > 0.05). However, significant difference was observed in the MA% of the right parotid gland (P = 0.025). Conclusion: Salivary gland function was found to deteriorate after RIT, with the parotid glands affected more than the submandibular glands.

Bronchobiliary fistula (BBF), a rare complication of liver disease, is an abnormal communication between the biliary tract and bronchial tree. BBF may occur as a consequence of local liver infections such as hydatid or amebic disease, pyogenic liver abscess or trauma to the liver, obstruction of biliary tract, and tumor. As such management of liver disease with BBF is very difficult and often associated with a high rate of morbidity and mortality. Therefore, timely diagnosis of BBF is imperative. Hepatobiliary scintigraphy along with hybrid single photon emission computed tomography/computed tomography using Tc99m-mebrofenin is a very useful noninvasive imaging modality, in the diagnosis of BBF.

Primary neuroendocrine tumors of the liver are a diagnostic challenge. We present a rare case of primary hepatic neuroendocrine tumor in which Ga-DOTATATE PET/CT imaging played an important role in the diagnosis and follow-up.

The occurrence of left bundle branch block (LBBB) in electrocardiogram during exercise testing is a relatively rare finding. The incidence of LBBB during exercise testing ranges from 0.5% to 1.1%. The mechanism of exercise-induced LBBB (EI-LBBB) is poorly understood, but ischemia is a proposed etiology. Stress myocardial perfusion imaging (MPI) can be useful in patients with EI-LBBB to rule out coronary artery disease. Adenosine vasodilator stress is the preferred mode of stress in patients with LBBB for performing stress-MPI. Here we present an interesting case of adenosine-induced LBBB during stress-MPI in a 67-year-old female patient with normal coronary angiography.

Whole body bone scintigraphy is most commonly used imaging modality to detect and assess the extent of osteoblastic osseous metastases in malignant conditions, though visceral metastases need additional imaging. The authors describe a case of 50-year-old postoperative breast cancer female where bone scintigraphy showed soft tissue uptake in thorax and hepatic region in addition to multiple skeletal metastases, indicating the involvement of three different organs by metastatic disease. The present case highlights that extraosseous tracer uptake in addition to abnormal osseous tracer uptake may raise the suspicion of widespread and visceral metastatic disease and warrant further evaluation in the form of cross-sectional and correlative imaging.

Herein, we report the synthesis of BaSnO3 (BSO) from molten salts (BSO1) and test its efficacy as an ethanol sensor, for the first time. BSO was also synthesized using a more well-established coprecipitation method (BSO2), and the influence of the synthesis method on morphology, microstructure and surface chemical composition of BSO was compared using electron microscopy, x-ray diffraction and photoelectron spectroscopy. Both BSO1 and BSO2 exhibited their best responses to 100 ppm of ethanol at 260 °C, but BSO1 showed higher response (12.5) and lower detection limit (0.5 ppm) compared to those of BSO2 (8.2 and 1 ppm) suggesting its superior ethanol sensing properties. The improved sensing of BSO1 was correlated with the corresponding surface morphology and chemical composition.

Background:PET/CT imaging of synovial angiogenesis using68Ga-RGD (cyclic tripeptide agent targeting αvβ3integrin) to study disease activity in rheumatoid arthritis (RA) has been demonstrated earlier in a few patients. However, post treatment changes in disease activity on68Ga-RGD2PET/CT imaging have not been adequately assessed.Objectives:To compare the performance of68Ga-RGD2PET/CT with disease activity score (DAS) 28 in assessing disease activity and treatment response in RA.Methods:Thirty patients (24F, 6M) aged 43±12 years with clinically diagnosed RA were prospectively studied. After calculation of DAS28 by a rheumatologist, all 30 patients underwent68Ga-RGD2PET/CT scan. Of these, 27 patients underwent a second68Ga-RGD2PET/CT scan and clinical assessment after at least 3 months of treatment. Total body and regional images of the upper limbs were acquired and interpreted by two nuclear medicine physicians blinded to the clinical findings. Joints showing focally increased tracer uptake compared to the background were considered positive and joints showing uptake equal to or less than background were considered negative. Data of 30 patients were used for inter-observer and inter-modality agreement calculations. Changes in PET parameters and DAS28 were compared in 27 patients to assess treatment response.Results:Out of 1560 joints examined in the initial scan, 394 were positive on PET/CT compared to 348 on clinical evaluation. Inter-observer agreement between nuclear medicine physicians was excellent (Cohen’s kappa 0.92, p68Ga-RGD2PET/CT included objective assessment, whole body evaluation of all small and large joints, and greater reproducibility.Conclusion:68Ga-RGD2PET/CT is a promising tool for objective assessment of disease activity and treatment response in patients with RA.Table 1.Clinical and PET parameters of the patientsParameterInitial data (n=27)Mean (SD)/Median (IQR)Follow-up data (n=27)Mean (SD)/Median (IQR)TJC(28)10 (5-13)3 (2-4)SJC(28)6 (3-7)1 (0-2)ESR25 (20-41)24 (18-35)PtGA6.0 (5.0-6.0)3.0 (2.0-4.0)DAS28(3)5.14 (0.85)3.74 (0.88)DAS28(4)5.60 (0.90)3.80 (0.96)PET positive Joints12 (7-8)4 (2-9)aSUVmax2.08 (1.68-2.52)1.79 (1.00-2.06)hSUVmax3.45 (2.71-4.70)3.34 (1.95-4.25)TJC/SJC: tender/swollen joint counts; ESR: erythrocyte sedimentation rate; PtGA: patients global assessment scale; DAS: disease activity score; aSUVmax/hSUVmax: average/highest SUVmax (maximum standardized uptake value); SD: standard deviation; IQR: interquartile rangeFigure 1.68Ga-RGD2PET scan of a 26-year female RA patient on treatment.A.Initial scan shows increased tracer uptake in multiple joints of upper and lower limbs and tendon sheaths of hands and ankle region (arrows); DAS28 was 4.56 (moderate disease activity) and ESR 12 mm/1sthour.B. Follow-up scan after 4 months shows resolution of tracer activity in the previously involved joints with only a mild focus persisting in the left knee joint; DAS28 was 1.73 (clinical remission according to ARA) and ESR 08 mm/1sthour.Acknowledgments:This study was supported by Indian Council of Medical Research, New Delhi [grant no.3/2/June-2017/PG-Thesis-HRD (23)]Disclosure of Interests:None declared

Ethanol sensing is an important area of research given its relevance to human health, traffic control and various industries. Metal oxide semiconductor nanostructures are most commonly used as gas sensors. In this study, enhanced ethanol sensing properties were obtained by incorporation of Gd3+ ions into Barium Stannate (GBSO), a bimetallic oxide microrods prepared through a simple co-precipitation method. The GBSO films, when exposed to ethanol, showed that incorporation of Gd improved the sensing response till 3 wt% of Gd (3GBSO) loading while further increase in Gd content resulted in reduced response. 3GBSO sample showed response as high as 76 to 500 ppm of ethanol vapor at an operating temperature of 220 °C along with a very low detection limit of 0.1 ppm (response of 1.5). Good repeatability and moderate stability were also observed suggesting its potential as low-cost ethanol sensor. Significant increase in both specific surface area as well as oxygen content (as measured by x-ray photoelectron spectroscopy) was observed in 3GBSO sample compared to that of BSO. Thus, we showed that incorporation of Gd improved the surface area of BSO microrods and in turn the surface adsorption of oxygen which led to their enhanced response to ethanol.

68Ga-labeled prostate-specific membrane antigen (PSMA) ligand positron emission tomography/computed tomography imaging (PET/CT) is a rapidly evolving imaging modality for prostate cancer. Many studies have proved its superiority in staging, restaging, and detecting the recurrent prostate cancer. However, case reports describing the incidental tracer uptake in benign and nonprostatic malignancies are also reported in the literature, thus questioning the specificity of the tracer. This pictorial assay illustrates the nonspecific tracer uptake encountered during PSMA PET/CT imaging, knowledge of which can increase the confidence of interpreting physicians and may also open a new path for peptide receptor radionuclide therapy in nonprostatic malignancies.

Purpose Male breast cancer (MBC) is a rare malignancy, with recurrence being one of the main adverse predictors for prognosis. The aim of the study was to evaluate the diagnostic and predictive value of fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT in the setting of suspected recurrence of MBC. Patients and methods Retrospective analysis of PET/CT findings was performed in 23 previously treated, histologically proven patients with MBC (mean age: 59.3±10.9 years; range: 36–79 years) with suspected recurrence. Kaplan–Meier disease-specific survival analysis was made with respect to histological, hormonal profile as well as PET/CT findings. Results Of the 23 patients, 19 (82.6%) showed recurrence. Recurrence at primary site with/without regional/distant site recurrence was seen in 12 (52.2%) patients. Only metastatic recurrence without primary site was seen in seven (30.4%) patients. Bone was the most common site of distant metastasis (14/23) followed by lungs (9/23), liver (4/23), brain (2/23), and adrenal (1/23). No recurrence (regional/distant) was noted in 4/23 (17.3%) patients; however, three of them had 18F-FDG-avid soft tissue lesions in esophagus, rectum and tongue, correspondingly, confirmed as second primaries with histopathology. Disease-specific survival analysis yielded nodal (P=0.01) as well as distant metastases (P=0.02) as the main survival predictors on PET/CT. Lung (P=0.001), followed by liver (P=0.009), and skeletal (P=0.01) metastases were the most adverse survival predictive factors. Conclusion 18F-FDG PET/CT showed good diagnostic and prognostic utility in recurrent MBC. It was better than bone scan in evaluation of skeletal metastases. Most importantly, 18F-FDG PET/CT helped in early detection of second malignancy and their clinical management in studied patients.

Objective: Langerhans cell histiocytosis (LCH) is a rare disorder of clonal proliferation of dendritic cells usually affecting children. However, it may also appear later in life at any age. The severity of the disease varies widely, and multi-system involvement of the lungs, liver and hematopoietic system may be life threatening. This study evaluated the role of 18F-fluorodeoxyglucose positron emission tomography / computed tomography (FDG PET/CT) in patients with single system and multisystem LCHfor disease extent, restaging and response to therapy. Methods:We retrospectively evaluated the data of 37 patients (27 male, 10 female) aged 21.3 ± 18.9 years, comprising 20 children (aged 1-16 years) and 17 adults (aged 20-69 years) with pathologically confirmed LCH. All patients had undergone whole body FDG PET/CT to assess the extent of disease involvement between January 2011 and May 2019. A total of 52 scans were evaluated by two experienced nuclear medicine physicians. Increased FDG uptake with morphological changes on the corresponding CT images were interpreted as PET/CT positive and absence of FDG uptake or any structural lesion were considered PET/CT negative. The metabolic and morphological tumor status and response after chemotherapy were assessed. Out of 52 PET/CT scans, 25 scans were performed for initial work-up and the rest for restaging, follow-up or response evaluation. The results of PET/CT imaging were compared with CT or magnetic resonance imaging (MRI) reports (if available). Results: Of the 37 patients, 20 had multisystem disease (8 high risk, 12 low risk), while single system involvement was noted in 17 patients (9 unifocal, 8 multifocal). FDG PET/CT was positive in 32/37 and detected skeletal (n=28), lymph nodal (n=13), lung (n=5), liver (n=4), pituitary (n=3), ano-cutaneous (n=2) and thyroid (n=2) lesions. In the two groups, FDG PET/CT identified more lesions compared to CT or MRI in 22 patients, including bone, lymph nodal and ano-cutaneous lesions. Six patients with lung lesions had very low FDG avidity. FDG PET/CT upstaged the disease in 8 patients from single system disease to multisystem involvement (2 primary pituitary, 2 primary thyroid and 4 primary skeletal). PET positive lesions had SUVmax of 8.9 ± 3.7 (range 3.8 - 18.8). In patients with follow-up or response evaluation imaging, a complete metabolic response was noticed in the low risk group (n=7), while disease progression was noted in patients with high risk and multisystem involvement group (n=3). Conclusion:Except for lung lesions, FDG PET/CT is a better imaging modality than conventional imaging (CT/MRI) for initial staging as well as restaging and response evaluation in both single system and multisystem LCH. It also helps in management planning by upstaging the disease from single system to multisystem involvement. Citation Format: ANISH BHATTACHARYA, RAJENDER KUMAR, BHAGWANT RAI MITTAL. Is there a role for 18F-FDG PET/CT imaging in Langerhans cell histiocytosis? [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B040. doi:10.1158/1535-7163.TARG-19-B040

Ga-labeled prostate-specific membrane antigen (PSMA) PET/CT is emerging as new reference standard for imaging of prostate cancer because of superb diagnostic performance in disease staging and recurrence detection. However, a number of isolated reports have been published recently regarding the nonspecific uptake of Ga-PSMA in nonprostatic benign or malignant pathologies. We describe the case of a 76-year-old man who underwent Ga-labeled PSMA PET/CT for suspicion of prostate cancer. Whole-body PET/CT of whom revealed tracer avidity in lipomatous lesion involving the left sartorius muscle. Histopathologic examination of lesion revealed a well-differentiated liposarcoma.

We report a case of adenocarcinoma prostate treated previously with radical prostatectomy and hormonal therapy who underwent Ga-labeled prostate-specific membrane antigen PET/CT for recurrence evaluation. In addition to radiotracer uptake in the prostate bed, unusual intense prostate-specific membrane antigen uptake was also noted in the left adrenal gland. With a clinical suspicion of pheochromocytoma, Ga-DOTANOC PET/CT was done, which revealed tracer-avid left adrenal lesion.

To evaluate the feasibility and diagnostic performance ofThis prospective study included 114 patients (75 men, 39 women; mean age 51.3 ± 14.7 years, range: 18-90 years) who underwent PET/CT-guided biopsy of FDG-avid abdominal and pelvic lesions from October 2014 to December 2017. Of these patients, 54 had a prior inconclusive CT-guided biopsy. The biopsies were done with ARA assistance, and a real-time sample was obtained after confirming the position of the needle tip within the target lesion on PET/CT. Histopathology reports were reviewed to evaluate the diagnostic performance of the procedure. Clinical or imaging follow-up was done to confirm negative results.The lesions were successfully targeted in 110 of the 114 patients (96.5%) and yielded a pathological diagnosis. Pathological diagnoses were confirmed in 50 of the 54 patients with a prior inconclusive biopsy. Of the 110 lesions, 82 were malignant, 20 were benign, and 8 showed minimal residual FDG uptake at the end of treatment and had no active disease even on clinical and imaging follow-up of at least 3 months. Findings were true-positive in 102 lesions, false-positive in none, true-negative in eight and false-negative in four. The procedure showed sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 96.2%, 100%, 100%, 66.7 and 96.5%, respectively. No immediate complications or delayed life-threatening events were observed.Percutaneous biopsy of metabolically active abdominal and pelvic lesions with ARA assistance is a technically feasible, safe and accurate method for pathological diagnosis with high diagnostic performance. PET-guided biopsy is highly practical and useful in patients, especially in those with a previous inconclusive biopsy.

Testicular torsion is a common differential diagnosis of acute scrotal pain along with acute epididymo-orchitis, which may lead to testicular non-viability. Doppler ultrasound and testicular scintigraphy are two routinely used modalities for the assessment of testicular viability. However, in some cases, these investigations may prove inadequate in differentiating between the two entities with widely differing management. Here, we present a case of a 52-year-old male with questionable viability of testis, who was investigated initially using testicular scintigraphy and was further subjected to a regional 18F-FDG PET/CT scan, in view of inconclusive findings with the conventional modalities.

PET/CT with Ga-labeled prostate-specific membrane antigen (PSMA) is increasingly recognized as the best imaging modality for disease staging and detection of recurrent prostate cancer. Despite its name, PSMA expression has been reported in a number of nonprostatic benign and malignant pathologies. Apparently, angioneogenesis is the mechanism attributed to increased Ga-PSMA uptake at these sites. Here we illustrate the utility of Ga-PSMA in 5 nonprostatic malignancies that could open up new possibilities for diagnostics and theranostic concepts with PSMA labeled radioligands in nonprostate tumor entities.

The male breast cancer is very less common as compared with the female breast cancer. We report a case of 64-year-old man who presented with the history of lower urinary tract symptoms. The digital rectal examination revealed hard and nodular prostate, and serum prostate-specific antigen level was 23.4 ng/mL. Ga-labeled prostate-specific membrane antigen PET/CT revealed prostate-specific membrane antigen-expressing lesions in the prostate, axillary tail of the right breast, and axillary lymph nodes. Histology from prostate revealed prostate carcinoma, whereas fine-needle aspiration from the breast revealed invasive ductal carcinoma of the breast.

In this study, Tc MDM (bis-methionine-DTPA) SPECT was used for the detection and differentiation of recurrent/residual glioma from radiation necrosis and the results were compared with dynamic susceptibility contrast-enhanced (DSCE)-MRI and clinical findings.Twenty-eight patients (18 men and 10 women; mean ± SD age, 41.4 ± 15.03 years) with histologically proven glioma (grade IV, 14; grade III, 7; grade II, 7) who were planned for postsurgical standard radio/chemo therapy were recruited prospectively. All the patients underwent technetium Tc MDM SPECT/CT and DSCE-MRI imaging at 6 months after surgery/radio-chemotherapy, 9 of 28 patients also underwent SPECT imaging at 1 to 2 weeks after surgery.Tc MDM SPECT/CT analysis demonstrated significantly higher target to nontarget (T/NT) ratio of the radiotracer in tumor recurrence than in radiation necrosis (3.59 ± 1.70 vs 1.16 ± 0.42). Likewise, the normalized cerebral blood volume (nCBV) values in patients with tumor recurrence were also significantly higher than in radiation necrosis (5.16 ± 2.30 vs 1.63 ± 0.94). A positive correlation (rho = 0.823, P0.0001) between T/NT ratios and nCBV was observed. The cutoff T/NT ratios and nCBV values estimated by receiver operating characteristic analysis were greater than 1.50 (area under the curve, 0.944 ± 0.34) and greater than 2.12 (area under the curve, 0.931 ± 0.39), respectively. Combining the results of Tc MDM SPECT/CT, DSCE-MRI, and clinical findings, diagnosis of recurrent/residual glioma or radiation necrosis was made in 18 and 10 patients, respectively. Sensitivity and specificity of 2 techniques were comparable, that is, 92.0%: 78.6% for MDM SPECT/CT and of 92.0%: 71.4% for DSCE-MRI, respectively.Thus, combining MDM SPECT with DSCE MRI may provide an accurate method for differentiation of tumor recurrence from radiation-induced necrosis in glioma patients.

Disease activity in ulcerative colitis (UC) is best assessed clinically by Mayo score. 18-Fluorodeoxyglucose positron emission tomography-computerized tomography (FDG PET-CT) is a noninvasive imaging technique to assess extent, disease activity and response to treatment of UC, especially in high risk population or patients unwilling for endoscopy. We conducted a prospective observational study with the aim of assessing and correlating UC disease activity by clinical criteria, endoscopy, histology, serum and fecal biomarkers, and FDG PET-CT. Sixty eligible patients of UC were enrolled into three groups (26 remission, 24 moderate and 10 severe activity) as per Mayo score and FDG PET-CT was performed within 72 h of colonoscopy. ESR, CRP, and fecal calprotectin (FC) levels were determined for all patients. Of 60 enrolled patients, 10% patients had proctitis, 43.3% left-sided colitis, and 46.7% extensive colitis. ESR, CRP, FC levels, and rectal PET activity were significantly higher in groups with moderate and severe disease activity. Rectal PET activity showed a significant correlation with the Mayo score (k = 0.465, p

We present a case of decompensated liver cirrhosis with ascites, which had history of asterixis, impaired balance with swaying gait along with mild irritability since 1 month. F-fluorodeoxyglucose PET/CT (FDG-PET/CT) performed to rule out malignancy did not reveal any abnormal FDG avid lesion suspicious for malignancy but showed hypermetabolism in the bilateral basal ganglia and thalamus with reduced metabolism in cerebral cortices and cerebellum, suggesting hepatic encephalopathy.

Chylocolporrhea or chylous vaginal discharge is an extremely rare manifestation of chylous reflux syndrome. Continuous loss of chyle adversely affects quality of life and results in increased morbidity due to the chronic loss of nutrients. Diagnosis and management of this condition is very challenging.A 35-year-old multiparous lady presented with the chief complaints of excessive milky vaginal discharge for 10 years. Microscopic and biochemical analysis of vaginal discharge along with hysteroscopy confirmed diagnosis of chylocolporrhea. Lymphoscintigraphy along with magnetic resonance imaging revealed site of leakage from the right external iliac lymphatics. She was started on medium-chain triglycerides-rich diet and meticulous ligation of all visible megalymphatics with tension-free lymphovenous anastomosis was done to right external iliac vein.Chylocolporrhea can be managed successfully using operative and nonoperative modalities.

Sarcoidosis is a multisystemic disease presenting with well-defined, bilateral, symmetric hilar and right paratracheal lymph node enlargement. Recently, fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) has been used to stage and detect occult site of active inflammation in sarcoidosis. F-18 FDG PET/CT has become a cornerstone imaging modality in the modern lymphoma management, which can present with generalized lymphadenopathy including mediastinal. We present a case series, which shows how sarcoidosis can be a "great mimic of lymphoma" on F-18 FDG PET/CT and how histopathology is essential in diagnosing sarcoidosis and ruling out lymphoma.

A retrospective review of medical records of 80 children with thyroid dysgenesis (TD) was conducted to determine the association of gender and maternal age with TD. The study subjects were attending the Pediatric Endocrinology Clinic of our hospital which is a large tertiary care Multispecialty Pediatric Center located in Chandigarh, Northwest India. There were no gender differences (boys to girls’ ratio 1:1). Mean maternal age of 25.87 ± 4.17 yrs (range 19–35 yrs) was significantly higher as compared to the mean maternal age of 23.87 ± 3.34 yrs (range 18–39 yrs) of a reference group (p < 0.0001). Odds of being older than 30 yrs were higher in mothers of children with TD as compared to mothers of normal children (OR 3.23; 95% CI: 1.54–6.44) (p-value 0.0003). In conclusion, our data shows that advanced maternal age is more prevalent in children with TD.

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome, usually caused by small benign mesenchymal tumors. The localization of these tumors is challenging, however, essential for the management. We compared the utility of F-FDG PET/CT and Ga DOTATATE PET/CT to detect the site of primary tumor in patients with suspicion of TIO.Retrospective analysis of 6 patients with hypophosphatemic osteomalacia and suspicion of TIO was performed. Ga DOTATATE PET/CT study was performed in all 6 patients to localize the tumor. F-FDG PET/CT was performed in 4 of 6 patients. F-FDG and Ga DOTATATE PET/CT studies were performed within 1 week of each other. Both studies were interpreted blindly without the knowledge of other imaging findings.All patients had symptoms of osteomalacia and hypophosphatemia. All except 1 patient had increased level of fibroblast growth factor 23. The lag time (symptoms to PET diagnosis) ranged from 1.5 to 22 years. In 4 patients, where both studies were performed, F-FDG and Ga DOTATATE PET/CT were able to localize the tumor in 2 and 3 patients. Ga DOTATATE PET/CT detected tumor in 5 (83.3%) of 6 patients.Ga DOTATATE PET/CT performed better than F-FDG PET/CT and is useful in the detection of tumors causing oncogenic osteomalacia. Therefore, in clinically suspected cases of hypophosphatemic osteomalacia, Ga DOTATATE PET/CT may be performed as first-line imaging investigation to avoid delay in the treatment of this devastating but curable disease. However, further studies with large patient population are warranted to validate our data.

Brown tumor affects multiple bones in the body with variable clinical symptoms, which may be misdiagnosed as multiple bone metastases or primary bone tumor. In the present case report, we report the usefulness of 99mTc-MDP bone scan and 99mTc-MIBI whole body scan in differentiating brown tumor of hyperparathyroidism from giant cell tumor.

A 65-year-old patient, with a history of left hemi-thyroidectomy for adenomatous goiter 20 years previously, was found to have pulmonary lesions on chest X-ray, a brain lesion on computerized tomography (CT), and elevated serum thyroglobulin (Tg). While completion thyroidectomy revealed that no pathological evidence of thyroid malignancy, radioiodine-avid pulmonary, brain, and renal and bone lesions were identified on diagnostic as well as posttherapy whole body planar scintigraphy and single photon emission computed tomography-CT. Subsequent ultrasonography-guided biopsy of a renal nodule showed thyroid follicular cells. This case suggests that metastatic differentiated thyroid carcinoma should be suspected in asymptomatic patients with incidentally detected lesions, raised serum Tg, and history of thyroid lesions.

Heterogeneous patchy marrow uptake on fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in a histologically proven case of lymphoma is usually considered a virtually pathognomonic sign of lymphomatous involvement. Here, we present a young male patient of T-cell-rich non-Hodgkin lymphoma (NHL), an uncommon morphologic variant of diffuse large B-cell lymphoma (DLBCL), who had undergone three sequential PET/CT scans at our department during the course of his therapy. These images depict the need for careful direct comparison of the current study with the previous PET/CT studies to avoid erroneous interpretation.

Our rationale was to evaluate the role of

Objective To prospectively compare positron emission tomography-computed tomography (PET-CT) with conventional magnetic resonance imaging (MRI) and FNAC for diagnosis of non- traumatic vertebral lesions fracture in countries like India where tuberculosis is endemic. Methods Fifty four patients with non-traumatic spontaneous vertebral lesions were prospectively studied. All patients underwent CEMRI focusing on the spinal lesions, whole-body PET-CT and FNAC.Results were then analysed and compared with final diagnosis obtained either by FNAC or clinical follow up. Results Out of total 54 patients, FNAC from the spinal lesion could establish diagnosis in 36 patients (26 TB, 1 Fungal and 9 tumors). Of the remaining 18 patients, diagnosis could be established in 7 utilizing FNAC from other sites as dictated by PET-CT. In the remanining11 patients, the diagnosis and management was decided on the concordance of MRI and PET-CT. Conclusion All three investigations have their own advantages and pitfalls and they complement each other in reaching the final diagnosis. MRI has a better pick up rate (than PET-CT) for inflammatory lesions. PET-CT on the other hand has better sensitivity for malignant vertebral disease. Diagnosis was established if FNAC was conclusive. In cases where FNAC was inconclusive, an additional 38.9% patients' diagnosis could be established by FNAC from other sites of involvement as dictated by PET-CT. This was an incremental utility of PET-CT. When even this fails, there were two possible scenarios-MRI and PET-CT in concordance with each other. In such a scenario, the combined report of MRI and PET-CT was relied upon. The last sub group (where MRI and PET-CT were discordant and FNAC was inconclusive) still remains achilles' heel. Wide bore biopsy may help in establishing diagnosis in such group.