Non Target Shunting of Tc-99m Macroaggregates of Albumin and Radiolabeled Yttrium-90 Microspheres into Hepatic Falciform Artery - Less Observed Arterial Variant not to be Overlooked.

Identification of nontarget arteries is crucial prior to Yttrium-90 microspheres radioembolization. We present a case where an uncommon nontarget artery, the hepatic falciform artery was identified during work up for radioembolization and necessary preventive measures were taken to minimize the complications.

Role of dynamic and parametric whole-body FDG PET/CT imaging in molecular characterization of primary breast cancer: a single institution experience.

AIM: The aim of this pilot study was to assess the role of dynamic whole-body PET and parametric imaging in the biological characterization of primary breast cancer. MATERIALS AND METHOD: In total 24 histologically proven primary breast cancer lesions in 21 consecutive patients were retrospectively analyzed. Each patient underwent 18F-fluoro-deoxyglucose whole-body dynamic PET-CT before any treatment. Dynamic PET images were acquired in the list mode for a total duration of 70 min. The reconstructed parametric imaging generated Patlak plot-based 'Slope' and 'Intercept' images, from which parametric indices ki and DV were obtained. The standard uptake value (SUV) metric was also obtained by summing the last few frames of the dynamic study. ki, distribution volume (DV) and SUV were correlated with the histological tumor grade, biomarkers [hormone receptors and human epidermal growth factor receptor 2 (HER-2) neu expression] and molecular subtypes (A, B and C) as well as with tumor size, regional nodal metastases and distant metastases. RESULTS: The mean ki was found to be significantly higher in grade III than II lesions (P = 0.005), HER-2 neu positive status (P = 0.04) and molecular subtype B (P = 0.04) as well as in greater than T1 lesions(P = 0.0003 and P = 0.04, respectively) and node-positive lesions (P = 0.009). Though mean ki was not found to be significant for the hormone receptors status (P = 0.08), it showed the best correlation compared to the other parameters (P = 0.8 for DV and P = 0.1 for SUV). Spearman's correlation test, area under the curve (AUC) and mismatch percentage also revealed ki to predict tumor grade (AUC, 0.95; r = 0.7; P = 0.0001), HER-2 neu status and molecular subtypes (AUC, 0.81; r = 0.49 and P = 0.01) along with the hormone receptors status (AUC, 0.83; r = 0.32; P = 0.1). The mean DV failed to show any association with any of the biological or anatomical staging parameters. Though ki was found to be comparable to that of SUV in almost all the assessed parameters, it appeared to be better for predicting hormone receptors status even though both parameters were not statistically significant. CONCLUSION: Our initial observation in a small cohort of breast cancer patients suggests that ki is promising in stratifying primary breast cancer lesions according to the tumor grade and biological characteristics.

Metabolically Active Subacute Infarct Masquerading as Metastasis: A Finding not to be overlooked in Asymptomatic Oncology Patients.

A 50-year-old man with carcinoma of the right buccal mucosa underwent staging whole-body 18F-fluorodeoxyglucose positron emission tomography-computed tomography, which revealed a hypermetabolic heterogeneously enhancing lobulated primary lesion in the right buccal region and an incidental finding of subacute stroke. The case highlights the importance of discriminating brain neoplasms mimicking stroke from true ischemic stroke, which is crucial for appropriate management of patients in an oncology setting.

Cardiac Tuberculosis on 18 F-FDG PET Imaging-A Great Masquerader of Cardiac Sarcoidosis.

A young gentleman with suspected cardiac sarcoidosis and LV dysfunction whose CMR revealed multifocal subepicardial to mid myocardial linear enhancement in the left ventricular myocardium underwent cardiac 18F-FDG PET imaging. The images revealed patchy regions of increased FDG uptake involving the apical to mid anterolateral, mid to basal anteroseptal/ right ventricular and mildly increased FDG uptake in apical inferior segments of the LV myocardium concordant with CMR findings. Whole body PET CT imaging showed multiple hypermetabolic supra and infra diaphragmatic lymphadenopathy, with no pulmonary lesion identified. Biopsy from the left para aortic lymph node revealed necrotizing granulomatous inflammation consistent with tuberculosis. Based on the histopathological findings of the lymph nodes, diagnosis of cardiac tuberculosis was made, given the similar imaging appearances in both sarcoidosis and TB. This case highlights that cardiac TB although rare, should be included in the differential diagnosis in patients with suspected infiltrative cardiomyopathy, particularly in TB endemic regions.

Unusual presentation of metastatic carcinoma cervix with clinically silent primary identified by (18)F-flouro deoxy glucose positron emission tomography/computed tomography.

Carcinoma cervix is the most common gynecological malignancy among Indian women. The common symptoms at presentation include abnormal vaginal bleeding, unusual discharge from the vagina, or pain during coitus and postmenopausal bleeding. Rarely, few patients may present with distant metastases without local symptoms. We present two patients with an unusual presentation of metastatic disease without any gynecological symptoms, where (18)F-flouro deoxy glucose positron emission tomography/computed tomography helped in identifying the primary malignancy in the uterine cervix.

Change in the diagnosis from classical Hodgkin's lymphoma to anaplastic large cell lymphoma by (18)F flourodeoxyglucose positron emission tomography/computed tomography: Importance of recognising disease pattern on imaging and immunohistochemistry.

Anaplastic large cell lymphoma (ALCL) is a rare type of nonHodgkin's lymphoma (NHL), but one of the most common subtypes of T-cell lymphoma. It is an aggressive T-cell lymphoma, and some ALCL may mimic less aggressive classical HL histopathlogically. It may be misdiagnosed unless careful immunohistochemical examination is performed. As the prognosis and management of these two lymphomas vary significantly, it is important to make a correct diagnosis. We describe a case who was diagnosed as classical HL by histopathological examination of cervical lymph node, in whom (18)F-flouro deoxyglucose positron emission tomography/computed tomography appearances were unusual for HL and warranted review of histopathology that revealed anaplastic lymphoma kinase-1 negative anaplastic large T-cell lymphoma, Hodgkin-like variant, thereby changing the management.

Peritoneovenous shunt scintigraphy to assess shunt patency in patients with refractory ascites.

Peritoneovenous shunt scintigraphy is an infrequently performed study to non-invasively assess shunt patency in patients with recurrent or refractory ascites in cirrhotic patients. We describe two patients of chronic liver disease in whom (99m)Tc-macroaggregated albumin scintigraphy was performed to assess the patency of peritoneovenous shunt. Visualization of lung activity was interpreted as indicative of shunt patency. While both lungs were visualized almost immediately in the first patient, they were visualized by 30 min in the second patient. Visualization of radiolabeled peritoneal fluid in the entire length of the shunt tubing may be variable, and was seen in only one patient. Scintigraphy also helped in excluding communication between the ascites and right groin collection in the second patient.

Popliteal node visualization during standard pedal lymphoscintigraphy for a swollen limb indicates impaired lymph drainage.

OBJECTIVE: The objective of our study was to examine the frequency and significance of visualization of popliteal nodes during lymphoscintigraphy for the investigation of lower extremity swelling. MATERIALS AND METHODS: Technetium-99m-labeled nanocolloid was injected subcutaneously in the first web spaces of both feet of 204 consecutive patients (69 males, 135 females; age range, 11-79 years) undergoing routine, clinically indicated lymphoscintigraphy; imaging was performed 5, 45, and 150 minutes after injection. The patients were asked not to undertake any vigorous exercise between the injection and completion of imaging. RESULTS: No popliteal nodes were visualized in 29 patients in whom there was no evidence of lymphedema on clinical or lymphoscintigraphic examination (group 1). Unilateral or bilateral popliteal nodes were visualized in 10 of 39 patients (25.6%) with clinical evidence of lymphedema but normal lymphoscintigraphy findings (group 2) (p < 0.005 vs group 1). In 136 patients with clinical evidence of lymphedema and abnormal lymphoscintigraphy findings (group 3), unilateral or bilateral popliteal nodes were visualized in 59 (43.4%) (p < 0.0001 vs group 1). Popliteal nodes were visualized in 40 of 73 limbs with "dermal backflow" (54.8%) and 42 of 335 limbs without dermal backflow (12.5%) (p < 0.0001). CONCLUSION: Popliteal node visualization after subcutaneous foot web space injection is an important sign of abnormal lymphatic function in patients with clinical lymphedema of the lower extremities.

Unusual initial manifestation of metastatic follicular carcinoma of the thyroid with thyrotoxicosis diagnosed by technetium Tc 99m pertechnetate scan: case report and review of literature.

OBJECTIVE: To report a case of metastatic thyroid cancer diagnosed on a technetium Tc 99m pertechnetate (TcO4-) thyroid scan. METHODS: We present the clinical findings, laboratory results, imaging studies, and surgical pathology report in a man with thyrotoxicosis in whom metastatic well-differentiated thyroid cancer was diagnosed incidentally on a routine TcO4- thyroid scan in the setting of a presumed diagnosis of benign toxic thyroid disease. In addition, we review the literature regarding coexistence of metastatic thyroid cancer and thyrotoxicosis. RESULTS: A 68-year-old man with thyrotoxicosis was referred for radioiodine therapy. A routine TcO4- thyroid scan revealed high-grade extrathyroidal uptake in the right upper hemithorax as well as in the left side of the thorax. In view of this finding, radioiodine treatment was deferred; further imaging with computed tomography revealed a 6.5-cm mass in a rib on the right side. A biopsy of the rib confirmed the presence of metastatic follicular carcinoma of the thyroid. Scintigraphy revealed sites of metastatic involvement predominantly in the bones along with a cold nodule in the left thyroid lobe, consistent with the primary tumor. CONCLUSION: This case emphasizes the impact of scintigraphic findings on determining the correct management of a patient who would have otherwise undergone inappropriate treatment. Through an extensive literature review, the incidence of malignant involvement in hyperfunctioning thyroid glands and the possible role of sodium iodide symporter expression by thyroid cancer metastatic lesions in preoperative detection of metastatic sites are addressed.