Aim and Objectives: The aim of this study is to assess the added value of hybrid fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the evaluation of extranodal involvement in patients with lymphoma in comparison to contrast-enhanced CT (CECT). Patients and Methods: All patients had lymphoma, proved by histopathological and immunophenotyping examinations. They underwent CECT and F-18 FDG PET–CT studies. Both CECT and PET/CT studies were done within 30 days. Results: The study included 144 patients 92 (63.9%) males and 52 (36.1%) females with mean age 49.3 years (range 18–80 years). A total of 102 (70.8%) patients had non-Hodgkin lymphoma and 42 patients (18.1%) had Hodgkin disease, diffuse large B-cell lymphoma subtype had the highest prevalence 52.8% (76/144), whereas lymphocytic predominance was the least prevalent 1.4% (2/144) followed by mucosa-associated lymphoid tissue lymphoma 2.8% (4/144) and small lymphocytic type 4.2% (6/144), mixed cellularity (MC), T-cell, and follicular type were equally distributed 6.9% (10/144 each). The lung was the most common site as it was involved in 34 patients followed by bone and bone marrow 32 patients, spleen 18, liver 16, nasopharynx 8, stomach 6, cutaneous and subcutaneous tissue 6, peritoneum, cecum, small intestine, brain, and intramuscular four patients each. However, the parotid and pancreas were the least common sites two patients each. The overall sensitivity, specificity PPV, NPV, and accuracy of PET/CT and CECT are 97%, 20% 94.2%, 33.3% and 91.7% and 89.6%, 60%, 96.8%, 30% and 87.5%, respectively. Conclusion: F-18 FDG-PET/CT can accurately monitor the extranodal lymphoma, it can detect metabolically-active lesions without CT structural changes and identify viable tumor in normal size lymph nodes. FDG-PET/CT is more effective than CECT in evaluating extra nodal lymphomatous infiltration, especially in the spleen, bone, and bone marrow.

Aim: In newly diagnosed carcinoma breast cancer patients, comparing conventional staging and 18F-fluorodeoxyglucose positron-emission tomography–computed tomography (¹⁸F-FDG PET/CT) staging. Materials and Methods: This was a retrospective observational study. A total of 171 new diagnosed carcinoma breast patients who underwent staging ¹⁸F-FDG PET/CT scan and routine conventional imaging including mammosonography of breast and axilla, chest X-ray, ultrasound sonography abdomen, and bone scan were included in the study. Staging was done according to the American Joint Committee on Cancer staging (tumor-node-metastasis). Changes in staging and management with ¹⁸F-FDG PET/CT scan were assessed. Results: Overall PET/CT upstaged in 22.2% of cases and changed management in 15.78% of cases. PET/CT upstaged in three of eight cases in Stage IA patients but changed management in only one case. In Stage IIA, of 31 patients PET/CT upstaged in two patients (6.45%). In Stage IIB, of 45 patients PET/CT upstaged in six patients (13.3%). In Stage IIIA, of 22 patients PET/CT upstaged in six patients (27.2) and in five patients there is a change in management. In Stage IIIB, of 43 patients PET/CT upstaged in 21 patients (48.8%) with change in management in 13 patients (25.5%). Conclusion: ¹⁸F-FDG PET/CT scan can be helpful in a significant number of patients with Stage IIB and above in upstaging and changing management.

Purpose of Study: To evaluate and compare imaging findings using computed tomography (CT) alone and positron emission tomography/CT (PET/CT) fusion imaging in posttreatment carcinoma cervix patients for recurrence. Subjects and Methods: From June 2014 to May 2016, 50 posttreatment carcinoma cervix patients were referred to our institution for PET/CT imaging. In all 50 of these patients referred for evaluation, a reliable reference standard was available. The reference standard was established by histopathological examination of accessible locoregional and nodal/distant metastatic involvement or follow-up of patients. CT and PET/CT were performed and analyzed for locoregional, pelvic nodal, and distant metastasis involvement in posttreatment carcinoma cervix cases. Results: In the evaluation of locoregional involvement, CT alone was found to have a sensitivity of 75% and specificity of 90% while PET/CT was found to have a sensitivity of 95% and specificity of 100%. Furthermore, in evaluation of pelvic nodal involvement, CT alone was found to have a sensitivity of 72% and specificity of 92.6% while PET/CT was found to have a sensitivity of 95.5% and specificity of 92.9%. In context to distant metastasis involvement (including para-aortic nodes), CT alone was found to have a sensitivity of 91.7% and specificity of 96.2% while PET/CT was found to have a sensitivity of 95.8% and specificity of 100%. PET/CT fusion in comparison to CT alone is better in sensitivity and specificity in the detection of locoregional involvement, pelvic node invasion, and distant metastasis in posttreatment carcinoma cervix cases.

Introduction: Forced diuresis technique is often adopted to wash out the high amount of urinary radioactivity that masks the foci of abnormal uptake in the pelvic region on ⁶⁸Ga-PSMA-HBED-CC positron emission tomography/computed tomography (PET/CT) scan in prostate cancer (PC) patients. However, this method is time-consuming, makes the patient non/less compliant, and is not feasible in patients with renal dysfunction. We hypothesized that early dynamic imaging can obviate the need for a postdiuresis view as the urinary activity is expected to be low at the time. Materials and Methods: A total of 20 biopsy-proven PC patients who were referred to our department for a ⁶⁸Ga-PSMA PET/CT for staging/restaging were prospectively studied. Dynamic PET/CT was done with on table intravenous (i.v.) injection of 2–3 mCi (74–111 MBq) of the radiotracer. Dynamic images were acquired over the pelvis with a frame time of 1 min for 10 min. Static images of 2 min/bed position were acquired between 45 and 60 min p.i. The patients were then administered i.v. furosemide and encouraged water intake and frequent urination. A static view of pelvic region was acquired at 5 min/bed at 120 min p.i. A three-dimensional volume of interest (3D-VOI) was plotted on the primary lesion, bladder, involved nodes if any, pelvic bones at involved and uninvolved sites, gluteal muscles, and artery. The sentence seems fine. This was to generate the Time activity curve for analysis. Results: Nine patients were referred for staging and 11 for restaging. Mean age of 20 patients was 64.6 years, and median prostate-specific antigen level was 21.4 ng/ml (range: 0.05–2180). Prostatic lesion was present in 20 patients, nodal involvement in 8, and bone involvement in 10 patients. Median maximum standardized uptake value (SUVmax) of the prostatic lesion (P) showed an ascending trend: 5.31 at 5 min, 10.65 at 60 min, and 10.52 at 120 min p.i. At the same time, median SUVmax of the bladder (B) also progressed steeply and then decreased postdiuresis: 1.01 at 5 min, 24.6 at 60 min, and 6.88 at 120 min. Despite forced diuresis, the bladder activity remained higher than that during early dynamic imaging. Median prostate-to-bladder (P/B) ratio was highest during early dynamic imaging at 5 min p.i. was 5.17, while at 60 min, P/B ratio was 0.42 (P = 0.002) and, at 120 min, it was 1.27 (P = 0.009). Further, all the nodal and bone lesions were clearly visualized on early dynamic images. Conclusion: The study results suggest that early dynamic imaging performs better than a postdiuresis view in terms of delineation of prostatic and regional lesions on 68Ga-PSMA scan. Further, it saves time and the patients are more compliant to this technique.

Purpose: The aim of the study was to estimate the radiation burden to personnel performing robotic arm-assisted positron emission tomography/computed tomography (PET/CT)-guided metabolic biopsies and to staff assisting the procedure in a PET/CT facility. Materials and Methods: We estimated the whole-body exposures to physicians and staff based on the dose rate measurement with an ionization chamber-based calibrated survey monitor and pocket dosimeters during the robotic arm-assisted 2-[F-18]-fluoro-2-deoxy-D-glucose PET/CT-guided biopsies from September 2016 to February 2017. In addition, we also noted the time to biopsy after injection and total biopsy time during which the staff was exposed to the radiation. Results: In this prospective study, PET/CT-guided biopsy was performed in 50 patients (males – 36, females – 14) with a mean age of 54 ± 15 years (range17–78 years). Of the 50 biopsy procedures, 18 were lung biopsies, 10 were bone biopsies, and 22 biopsies were from abdomen/pelvic lesions. The mean time taken for the procedure was 26 ± 11 min. The mean time elapsed between injection and procedure was 182 ± 85 min and mean injected activity of 138.38 ± 74 MBq. The mean whole-body exposure per procedure to an interventionist and an assistant was 1.88 ± 0.82 μSv and 1.04 ± 0.75 μSv, respectively. The mean exposure rates at 0-m and 1-m distance from the patient were 30.77 ± 14.61 μSv/h and 2.59 ± 1.49 μSv/h, respectively. Conclusion: We conclude that the interventionist received the highest mean effective dose as compared to the helping staffs. The occupational radiation exposure was found to be within the limits as specified by the regulatory authorities (International Commission on Radiological Protection-103), and PET/CT-guided biopsies were safe from radiation protection point of view.

Dacryoscintigraphy is a noninvasive, simple, easy to perform imaging modality used in the evaluation of epiphora. However, it is an infrequently done study in nuclear medicine departments. A standardized protocol and a systematic interpretation of the scans help in answering the queries of the clinicians in cases of epiphora. We have attempted to build a pictorial essay of the various findings detected on dacryoscintigraphy.

Poorly differentiated thyroid carcinomas (PDTC) are a subgroup of thyroid cancers with aggressive behavior and worse prognosis compared to the well DTC. Limited diagnostic tools and therapeutic options exist for such cases, and the appropriate management algorithm continues to evolve in this subgroup. They pose difficulty in clinical management due to their behavioral heterogeneity and increased occurrence of aggressive clinical behavior underlining the need for management individualization. In the present communication, a case series of three clinically challenging cases of PDTC (with low serum thyroglobulin (Tg) and iodine nonavidity) are presented with a discourse on their management intrigues, unresolved issues and the requirement of a distinctive management protocol. A small fraction of PDTCs may show low serum Tg values, with the questionable significance of its role for the assessment and monitoring of disease burden in this group of patients. Given uncommon occurrence, limited and variable literature data, management guidelines for “nonsecretor” PDTC needs to be more clearly defined based on scientific evidence. The present clinical case series of PDTC with low serum thyroglobulin in the context of noniodine concentrating metastatic disease and aggressive clinical course (”nonsecretor” status) was noteworthy from this viewpoint.

Castleman's disease (CD) is a rare benign lymphoproliferative disorder. We are presenting three cases of CD of which one is unicentric CD, and the other two are an idiopathic multicentric CD. One of the two multicentric cases is associated with POEMS syndrome. The whole body ¹⁸F-Fluorodeoxyglucose positron-emission tomography–computed tomography scan plays a significant role in identifying the centricity, distribution of disease, response to therapy, and in early detection of remission.

Multiple myeloma commonly involves the skeleton. Extraosseous disease is sometimes noticed involving various organs. We present a very unusual site of myeloma involvement in the thyroid gland and thyroid cartilage.

Silicone implant incompatibility syndrome (SIIS) has been identified as a cause of systemic symptoms such as lymphadenopathy, myalgia, and dyspnea in patients with silicone implants. We present a case of 76-year-old female patient, treated for carcinoma left breast with mastectomy and silicone breast implant, chemotherapy, and radiotherapy 42 years ago. There was a history of implant rupture and removal 2 years ago. The patient presented with right axillary swelling and dyspnea. 18-fluorine fluoro-deoxy-glucose positron emission tomography/computed tomography (F-18 FDG PET-CT) showed mildly FDG-avid left anterior chest wall and right rectus abdominis deposits, multiple lymph nodes, and low-grade FDG-avid pneumonitis changes in both lungs. Biopsy from the chest wall and rectus abdominis deposit was negative for malignancy and revealed foamy histiocytes and foreign-body giant cell reaction, indicative of SIIS. SIIS is a mimic for metastases and should be considered as a differential diagnosis in FDG PET-CT interpretation in patients with silicone breast implant.

Primary malignancies of the salivary gland itself are uncommon, while secondary metastatic deposits are further very rare with description of only few case reports in the literature. The most common site of metastatic deposit to parotid gland is from squamous cell malignancies of head and neck, while secondary deposits from primary in infraclavicular location are very rarely described. We herein describe the case of an elderly lady who while on adjuvant endocrine therapy developed metastatic disease with right intraparotid node as the sole site of metastasis detected on FDG PET scan. This type of presentation of recurrence is very uncommon, especially in hormonal receptor-positive cases, with <30 cases described in the literature to the best of our knowledge. This patient underwent metastasectomy followed by palliative the second-line hormonal therapy and achieved long-term survival more than usually seen with other metastatic breast cancers highlighting the importance of metastasectomy in metastatic breast cancer patients on hormonal therapy who develop metachronous oligometastatic disease.

Goiter and hyperthyroidism are fairly common problems in the Indian population. We present a 49-year-old female who presented with thyroid swelling and suppressed thyroid-stimulating hormone. On evaluation, she was having latent hyperthyroidism with diffuse and soft thyroid swelling. During the evaluation for feasibility of radioiodine ablation, she was found to have thyrolipomatosis on computed tomography. She was counseled for total thyroidectomy and subsequently underwent the same with histopathology confirming the presence of fatty infiltration into the thyroid stroma.

A 55-year-old woman with newly diagnosed hepatocellular carcinoma (HCC) was hospitalized in our department for the evaluation of selective internal radiotherapy (SIRT), which consists of an angiography, an intra-arterial technetium (Tc)-99m-macroaggregated albumin application and Tc-99m sulfur colloid scintigraphy to assess liver function. Besides the modest intratumoral tracer accumulation, F-18-fluorodeoxyglucose (FDG) positron emission tomography–computed tomography (PET/CT) imaging showed two intense focal cuneiform splenic FDG accumulations which turned out to be splenic infarctions. Four months later, both hypermetabolic foci were completely regressive in the first follow-up PET/CT after SIRT. This is the first report of a complete metabolic regression of splenic infarctions within just 4 months, whereas regression on CT is commonly seen after more than 2 years.

The gamut of gallium labeled radiopharmaceuticals contributes to augmented variety in molecular imaging approach for in vivo identification of tumor characteristics. The spectrum ranges from somatostatin receptor based target-specific imaging agents, to those used for tumor imaging based on specific receptor types extending into ones used for therapeutic monitoring. The versatility of gallium chemistry provides the needed advantage for imaging which is further exploited in clinical practice influences the specificity of tumor imaging. Ga-68 has revealed applicability in labeling compounds from nanoparticles to micro as well as macromolecules. We in this image, present variety of frequently and infrequently used gallium labeled radiopharmaceuticals, for imaging diverse malignancies other than conventional established tracers.

Tc-99m labeled red blood cell (RBC) scintigraphy is commonly used in the evaluation of acute gastrointestinal (GI) bleeding. On Tc-99m RBC studies, GI bleeding is seen as an initial focus of increased radiotracer activity that on subsequent images increases in intensity and changes position in a pattern that confirms to segments of bowel. We report a case of a patient with multiple episodes of GI bleeding referred to detect the source of bleeding. A Tc-99m labeled RBC scan was performed and the findings showed a focal abnormal hot spot in the mid quadrant of the abdomen, seen promptly in initial dynamic images. Subsequent static and single-photon emission computed tomography-CT (SPECT-CT) images found it to be umbilical varices. Most varices fill promptly as in this case and should not be misinterpreted as a focus of hemorrhage. SPECT-CT should be used in such cases so that that false-positive interpretation can be avoided.

We present the case of a-55-year-old female patient who presented with dry cough. High-resolution computed tomography chest revealed multiple nodules in both lungs. ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) was done to look for the unknown primary. It showed hypermetabolic bilateral lung nodules, subcutaneous nodules involving lower limbs, an intramuscular nodule, enlarged paratracheal, and right axillary nodes. There was no primary tumor seen. The biopsy of subcutaneous nodule revealed panniculitis with the foreign body granuloma. Follow-up scans after 6 and 9 months showed spontaneous resolution of all lesions except for few right axillary nodes. There was no active treatment given, and the patient remains asymptomatic on follow-up. Here, PET/CT played a role in excluding a primary tumor, guiding the biopsy, and follow-up.

We present a case of a 42-year-old male patient affected by unresectable, chemorefractory cholangiocarcinoma, with prior placement of biliary stent. Because of the absence of extrahepatic metastases, he was submitted to liver-direct therapy with ⁹⁰Y-microspheres. ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) performed before the procedure showed intense tracer uptake in the hepatic lesion and along the biliary stent. The patient underwent radioembolization with ⁹⁰Y-resin spheres (1.1 GBq). ¹⁸F-FDG PET-CT, acquired 6 weeks after the procedure, showed no response of the hepatic lesion and the appearance of an area of markedly increased uptake extending through the inferior vena cava into the right atrium, confirmed as extensive tumor thrombus at the enhanced multislice CT subsequently performed. ¹⁸F-FDG PET-CT proved to be a useful imaging tool not only for the evaluation of metabolic response but also for the early detection of extrahepatic progression after 90Y-radioembolization.

The most common reason for intraluminal urinary bladder hematoma is trauma. However in gynecological and pelvic malignancies, the pelvic irradiation can affect non targeted organs resulting in urogenital complications like hematoma. Small size hematoma can be easily diagnosed in ultrasound. Large hematoma can mimic as neoplastic mass in imaging modalities.We present here an intresting image of intraluminal urinary bladder mass, where FDG PET CT was helpful to diagnose it as a non neoplastic mass.

Brown tumors are an uncommon entity associated with hyperparathyroidism. Initially described with primary hyperparathyroidism, with the widespread use of dialysis, they were also seen to be associated with secondary and tertiary hyperparathyroidism. These are lytic, expansile lesions causing bony pains, and depending on the size and extent, skeletal dysmorphism. The present case illustrates the detection of parathyroid adenoma with multiple brown tumors on ^99mTc-sestamibi parathyroid scintigraphy in a patient presenting with facial dysmorphism and multiple bony pains.

We present the case of a 47-year-old female with metastatic pancreatic neuroendocrine tumor (NET). The patient was treated with long-acting octreotide which failed to halt disease progression. The patient was being considered for 177Lu-peptide receptor radionuclide therapy, and a 68Ga-DOTANOC positron emission tomography-computed tomography (PET-CT) was acquired initially, which showed good uptake in the primary and metastatic lesions. Metastatic pancreatic NETs have limited treatment options, and given the background that these tumors are highly vascular and prostate-specific membrane antigen (PSMA) expression is known in the endothelium of tumor neovasculature, we decided to perform a 68Ga-PSMA-HBED-CC PET-CT scan. It revealed radiotracer uptake in the metastatic liver lesions although not as high as 68Ga-DOTANOC-PET-CT. PSMA expression needs to be researched further, especially in high-grade NETs where somatostatin expression may be poor.

Carotid body tumors, although representing about 65% of head and neck paragangliomas, are rare neoplasms. Doppler ultrasonography, contrast-enhanced computed tomography (CECT), and MRI have been routinely used in the diagnosis of carotid body tumor. We hereby represent a case of 56-year-old male suspected to have lymph node metastasis from carcinoma pyriform sinus detected as carotid body tumor in fluorodeoxyglucose positron-emission tomography-CECT imaging and subsequently confirmed by histopathology.

Prostate-specific membrane antigen (PSMA) expression has been shown in neovasculature of various malignancies. Recurrent medullary thyroid cancer (MTC) is difficult to treat. We present the findings on PSMA-positron emission tomography/computed tomography (PET/CT) of a 68-year-old man with MTC, who presented with a recurrent left paratracheal mass and rising calcitonin. The scan revealed significant uptake on PSMA imaging but not on ⁶⁸Ga-DOTANOC PET/CT. ¹⁷⁷Lu-PRRT is one of the therapeutic options in patients with recurrent MTC, but in this case was not possible due to lack of somatostatin receptor expression. Imaging evidence of PSMA expression alerts us to the potential use of ¹⁷⁷Lu-DKFZ-PSMA-617 therapy in such patients.

¹⁸F-Fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸FDG PET/CT) has shown an increasing role in the evaluation of urinary bladder cancer, though benign pathological processes of the urinary bladder can also result in increased FDG uptake. Leiomyomas of urinary bladder are benign mesenchymal neoplasms and a very rare bladder tumor comprising <0.5% of all bladder tumors. Here, we present the low-grade ¹⁸FDG uptake in urinary bladder leiomyoma on PET/CT done for the clinical suspicion of bladder cancer, which can be a rare differential for bladder carcinoma.