Umbilical Varices: A Potential Pitfall in Gastrointestinal Bleed Scintigraphy Interpretation.

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.

Bone Scan in Detection of Biological Activity in Nonhypertrophic Fracture Nonunion.

Biological activity of the fracture site is very important factor in treatment planning of fracture nonunion. If no biological activity is detected, then an autologous bone graft can be supplemented or osteogenic supplementations, such as bone morphogenetic protein is given. If biological activity is present, then secure fixation is sufficient to achieve bony union. Biological activity of nonunions is usually assessed by conventional radiographs. The presence of callus formation is usually assessed as the presence of biological activity. However, high number of radiologically nonhypertrophic nonunion demonstrates intense, uniform tracer uptake on bone scan, a sign of biological activity. Poor or absent callus visualization on radiographs does not always mean a lack of biological activity and it underestimates it. Uptake in bone scintigraphy reflects blood flow and new bone formation and being functional imaging technique, it is more suitable for assessing biological activity.

Metastatic Brachial Plexopathy with Brain and Spinal Metastasis in a Case of Recurrent Breast Carcinoma Demonstrated on 18F-FDG PET/CT.

We report a case of a 56-year-old woman diagnosed with infiltrating ductal carcinoma of the left breast, who had undergone left modified radical mastectomy followed by radiotherapy and adjuvant chemotherapy. FDG PET-CT showed metastatic brachial plexopathy with intra-spinal and extra-axial brain metastasis. Metastatic brachial plexopathy along with brain and spinal metastasis is a rare condition with very less incidence. The scan also showed left para-sternal anterior chest wall recurrence with antero-superior mediastinal metastasis. 18FDG-PET scanning is a useful tool in evaluation of patients with suspected metastatic plexopathy. It may also be useful in distinguishing between radiation-induced and metastatic plexopathy. Typical pattern of FDG uptake and dual time point imaging may increase specificity and require further evaluation.

Extensive Visceral Calcification Demonstrated on 99mTc-MDP Bone Scan in Patient with Carcinoma Penis and Hypercalcemia of Malignancy.

Hypercalcemia is a common life-threatening complication associated with several malignancies. Parathyroid-related peptide has been shown to cause hypercalcemia in several solid tumors but rarely in penile cancer. We report a case of penile cancer with hypercalcemia causing metastatic visceral calcification in lungs, liver, and stomach detected on bone scan without significant abnormalities on CT scan.

Feasibility study of axillary reverse mapping lymphoscintigraphy in carcinoma breast: A concept toward preventing lymphedema.

OBJECTIVE: In the surgery of breast cancer, axillary reverse mapping (ARM) is the identification and preservation of arm draining lymph node (ARM node) during an axillary dissection. The assumption is that the ARM node is different from node draining breast and is unlikely to be involved even in the patients with axillary nodal metastases. If we can identify and preserve ARM node using lymphoscintigraphy; morbidity of lymphedema, as seen with axillary dissection, may be avoided. MATERIALS AND METHODS: Pathologically proven 50 breast cancer patients undergoing initial surgery (cTx-4, cN0-2, and Mx-0) were included in this study. Less than 37 MBq, 0.5 ml in equally divided doses of filtered 99mTc sulfur colloid was injected intradermally into the second and third web spaces. ARM nodes in the axilla were identified with the help of Gamma Probe intraoperatively; however, their location was noted with the reference to specific anatomical landmarks and sent for histopathological examination after excision. RESULTS: The ARM node was successfully identified in 47/50 cases (sensitivity - 94%). In 40 out of 47 cases (85%), the location of the ARM node was found to lateral to the subscapular pedicle, above the second intercostobrachial nerve and just below the axillary vein. Of the 47 patients in whom ARM node/s were identified, metastasis was noted in 5 of them (10%). Four out of these 5 patients had the pN3 disease. CONCLUSION: ARM node exists, and it is feasible to identify ARM node using radio isotope technique with an excellent sensitivity. ARM node seems to have a fairly constant location in more than 80% cases. It is involved with metastasis (10% cases) only when there are multiple lymph nodal metastases in the axilla.

Dual malignancies in the setting of differentiated thyroid carcinoma: their synchronous or metachronous nature, impact of radioiodine treatment on occurrence of second malignancy and other associated variables.

PURPOSE: The primary objective of the study was to assess the risk for second primary malignancy after radioiodine treatment for differentiated thyroid carcinoma (DTC). Other objectives were to study the different variables associated with the occurrence of synchronous or metachronous dual malignancies in association with DTC. MATERIALS AND METHODS: The patient population studied comprised patients with histopathologically proven DTC referred for radioactive iodine treatment after thyroidectomy followed up at a single centre during the period from January 1963 to March 2011. The data collected were analysed with respect to different variables associated with two primary tumours in the setting of DTC. RESULTS: Out of the total 8614 patients studied from 1963 to March 2011, 44 dual malignancies in association with DTC were detected, showing a prevalence rate of 0.5%. The most common site of second primary malignancy was the head and neck (H&N) in men and the breast in women. Of the 44 dual malignancies, 18 were synchronous in nature and 26 were metachronous. In the metachronous group, thyroid carcinoma was the first primary malignancy in only 5/26 patients, whereas the remaining 21 patients had thyroid carcinoma as the second primary malignancy. In 5/26 patients in whom carcinoma of the thyroid was the first primary malignancy, the second primary malignancy was breast carcinoma in two cases, renal cell carcinoma in one case, colorectal carcinoma in one case and metastatic NET of unknown primary in one case. All these five patients received radioiodine treatment with different activities. In 21/26 patients in whom thyroid carcinoma was the second primary malignancy, the most common first primary malignancy comprised H&N tumours. In this group, 12 patients had a history of external beam radiotherapy (EBRT). Among synchronous malignancies (18/44 patients), H&N tumours were the most commonly associated. CONCLUSION: There was no significant risk for second primary malignancy after radioactive iodine treatment in patients with DTC. There is increased risk for thyroid malignancy after EBRT delivered for other primary tumours, especially in children. Hence, any thyroid abnormality on long-term follow-up of patients after EBRT for other tumours should be considered carefully. H&N malignancies are the most common synchronous, metachronous and overall associated second malignancy with thyroid carcinoma.

Hepatorenal cutaneous syndrome demonstrated by 99mTc macro aggregated albumin whole-body scintigraphy.

Hepatopulmonary syndrome, also known as hepatorenal syndrome, is a triad of liver disease, impaired oxygenation, and intrapulmonary vascular abnormalities. Forty-seven percent of patients with end-stage liver disease may have hepatopulmonary syndrome, an independent predictor of poor prognosis. Gross dilatation of pulmonary precapillary and capillary vessels, as well as an absolute increase in the number of dilated vessels, is the classic pathological description. We report a young man with cirrhosis demonstrating extrapulmonary shunting of 99mTc-MAA to kidneys with extensive peripheral arteriovenous (cutaneous) vasodilation, which we prefer to name as the "mosaic sign" in the absence of spider nevi or erythema.

Axillary reverse mapping using 99mTc-SC: a case illustration.

Lymphedema is a common complication in breast carcinoma patients undergoing axillary lymph node dissection. Although there is a significant reduction in the lymphedema rate with sentinel lymph node biopsy compared to axillary lymph node dissection, there is some risk after sentinel lymph node biopsy. Axillary reverse mapping, an emerging concept aims at identifying and preserving the draining lymph node of the arm that is invariably devoid of malignancy. This concept if validated may prevent lymphedema in breast carcinoma patients. Axillary reverse mapping node can be identified using a radiotracer or blue dye. We describe the procedure using filtered Tc-SC.

Tc-99m macro aggregated albumin scintigraphy - indications other than pulmonary embolism: A pictorial essay.

INTRODUCTION: Tc-99m macro aggregated albumin (MAA) is synonymous for lung perfusion scintigraphy and is part of the study in the evaluation of pulmonary thromboembolism. We wanted to highlight the utilities of Tc-99m MAA other than pulmonary embolism as a pictorial assay. MATERIALS AND METHODS: Patients referred for Tc-99m MAA scintigraphy under various indications were included in this pictorial essay. Commercially available TechneScan LyoMAA cold kit from Mallinckrodt Medical B.V., Holland was used. Acquisition protocols for different indications are described in this article. Different clinical indications (e.g., pulmonary artery stenosis, hepatopulmonary syndrome, FEV1 calculation in lung surgery planning, selective internal radiation therapy planning, venography for deep venous thrombosis, left to right cardiac shunts, etc.) where Tc-99m MAA scintigraphy was asked for; how it helped in different clinical scenarios and how it can be used clinically is explained with unique and interesting case examples and images. We also reviewed the literature to look for certain remote indications of MAA imaging for the sake of completion like - (shunt scintigraphy, peritoneopleural communication, etc.). CONCLUSION: Tc-99m MAA is a very useful radiopharmaceutical, which can be used for many other indications apart from the commonly used indication of lung perfusion scan in pulmonary embolism. It can provide useful clinical information in other indications, which we try to highlight in this article.

F-18 fluorodeoxyglucose positron emission tomography "super scan" in a patient of metastatic primitive neuroectodermal tumor of the kidney.

We report F-18 fluorodeoxyglucose (FDG) "positron emission tomography (PET) super scan" akin to "super scan" of conventional skeletal scintigraphy, in a rare case of primitive neuroectodermal tumor (PNET) of the kidney. A twelve year old male patient of metastatic PNET of the kidney was subjected to a "true" whole body F-18 FDG PET scan including lower limbs and skull region as per the institution protocol. The images revealed extensive hypermetabolic areas corresponding to the computed tomography described renal, hepatic, and pancreatic lesions along with intense and non-uniform uptake in the marrows of axial and appendicular skeletal system. Interestingly, low background tracer concentration was observed along with very low F-18 FDG uptake in the brain, skeletal muscles of limb, mediastinum, and bowel. In view of these findings, the scan can be interpreted as "PET super scan" due to its resemblance with the super scan of skeletal scintigraphy. A repeat F-18 FDG PET scan after chemotherapy revealed marked treatment response with disappearance of "super scan"-like pattern, reduction in number, size, metabolic activity of the lesions, and stimulated marrow sans the previously diseased portion. Though uncommon, the reporting physician should be aware of "PET super scan" and its implications as described in this case.