A 60-year-old male presented with complaints of dyspnea, intermittent fever, and 40 pounds of weight loss over the previous 9 months and was admitted for acute hypoxemic respiratory failure. Labs demonstrated elevated inflammatory markers, mild anemia, and thrombocytopenia. Fluorodeoxyglucose-positron emission tomography scan demonstrated diffusely increased pulmonary fluorodeoxyglucose uptake without corresponding abnormality on CT images. Excisional lung biopsy demonstrated intravascular large B-cell lymphoma (IV-LBCL). Presentation, imaging findings, and diagnosis of IV-LBCL will be discussed, as well as differential considerations for pulmonary involvement by IV-LBCL.

Background— Collateral damage to the vagal nerve and the upper gastrointestinal (UGI) system during atrial fibrillation ablation has not been systematically evaluated. Methods and Results— We performed a prospective, observational study assessing the effect of atrial fibrillation ablation on the function of the vagus nerve/UGI system. All patients underwent esophageal manometry, gastric emptying study, and sham-feeding test (corresponding to esophageal, gastric, and small intestinal function evaluation, respectively) before ablation (baseline) and subsequently at 24 hours, 90 days, and 180 days after the procedure. In addition, UGI symptom assessment using the patient assessment of upper gastrointestinal disorders–symptom severity index (PAGI-SYM) questionnaire was performed at baseline and during each of the subsequent evaluations. Of the 27 patients enrolled in the study, 9 (33%) patients had abnormal UGI function at baseline; defined as at least one of the 3 abnormal tests. At 24 hours after the radiofrequency catheter ablation, 20 (74%) patients had at least 1 new abnormality on the UGI function tests ( P <0.001). New onset esophageal dysmotility, delayed gastric emptying time, and abnormal sham-feeding tests were observed in 13 (48%), 13 (48%), and 9 (33%) patients, respectively. Mean PAGI-SYM scores increased from 7.78±6.6 at baseline to 15.56±13.4 ( P =0.002) at 24 hours. New onset abnormalities persisted in 9 (33%) patients at 3 months and normalized in all patients at 6 months. Conclusions— Atrial fibrillation ablation results in functional impairment of the UGI system, including the esophagus, stomach, and small intestine. This impairment is transient and is probably mediated by the injury to the components of the vagal nerve. Clinical Trial Registration— URL: http://clinicaltrials.gov . Unique Identifier: NCT01396356.

Purpose 11C-acetate positron emission tomography (PET) imaging allows for the detection of occult metastatic disease that may otherwise go undetected with standard imaging for prostate cancer (PCa). The aim of this study was to evaluate lymph node coverage of the standard Radiation Therapy Oncology Group (RTOG) whole pelvic radiation therapy (WPRT) field in patients found to have node-positive PCa determined by 11C-acetate PET imaging. Methods and materials A retrospective analysis was conducted on 125 PCa patients who underwent 11C-acetate PET scans at our institution between 2007 and 2014. Patients were included if they had evidence of nodal disease without distant metastatic cancer. Individual lymph nodes were characterized by location, size, and relationship to the RTOG WPRT field. Results A total of 55 11C-acetate PET scans (from 54 men) met criteria for inclusion in the study. Median age at diagnosis was 61 years. Median prostate-specific antigen values at diagnosis and at the time of the scan were 9.2 and 8.1 ng/mL, respectively. A total of 159 positive lymph nodes were identified, 78% of which were smaller than 1 cm. The most frequently involved lymphatic regions were the external iliacs (38.4%), para-aortics (19.5%), and common iliacs (16.3%). Additionally, 10.1% of positive nodes were identified as nodes of Cloquet. Of the positive nodes, 51.6% were determined to reside outside of the radiation field and, of those, the most common sites were para-aortic (36.9%), proximal common iliac (17.8%), distal external iliac (17.8%), and nodes of Cloquet (17.8%). Conclusions Based on 11C-acetate PET imaging in patients with PCa, the standard RTOG WPRT field may miss more than one-half of all positive lymph nodes. Clinicians should be aware of the potential for insufficient nodal coverage when using the standard RTOG WPRT field in patients with node-positive PCa. 11C-acetate PET imaging may be useful in defining target volumes for these patients.

The inguinal lymph nodes are an unusual site of metastases for prostate adenocarcinoma. We present a case in which a 61-y-old man with biochemically recurrent prostate cancer underwent attenuation-corrected 11C-acetate PET/CT, which demonstrated multiple foci of increased activity in the left inguinal, left iliac chain, and right inguinal regions. The attenuation-corrected CT portion of the scan also showed anterior wall thickening of the rectum. The imaging findings were suggestive of metastatic involvement of the rectum below the dentate line with subsequent spread to the inguinal lymph nodes.

Neutropenic sepsis is a common clinical entity occurring in postchemotherapy patients. Infection may not be the cause of fever in such patients after neutrophil-count recovery. Herein, we present two patients who developed fever during the neutropenic phase of induction chemotherapy and were treated with broad-spectrum antibiotics until they were no longer febrile and had recovered their neutrophil count. Being off antibiotics, they redeveloped fever within 48-72 hours. These fevers seemed to be secondary to postinfectious inflammatory response and not infection, supported by the fact that adequate antibiotic treatment was given and the collected fluid contained neutrophils but the cultures were negative. We hypothesize an explanation for this phenomenon based on the "homing of neutrophils" to bone marrow, which involves chemoattraction of CXC chemokine receptor ( CXCR)-4 expressed on neutrophils towards the chemokine stromal cell-derived factor ( SDF)-1 ( CXCL12) expressed constitutively by bone marrow. Literature has shown that elevation of SDF-1 levels at injured/ inflamed sites might create a similar gradient. This gradient results in the migration of neutrophils to the sites of previous injury/ inflammation, leading to the formation of sterile abscesses. Based on our cases, we also conclude that antibiotics do not prevent the formation or treat such sterile "abscesses"; however, the drainage of these "abscesses" and treatment with anti-inflammatory agents are useful in such cases.

Purpose The aim of this study was to identify which patient characteristics are associated with the highest likelihood of positive findings on 11C-acetate PET/computed tomography attenuation correction (CTAC) (PET/CTAC) scan when imaging for recurrent prostate cancer. Methods From 2007 to 2011, 250 11C-acetate PET/CTAC scans were performed at a single institution on patients with prostate cancer recurrence after surgery, brachytherapy, or external beam radiation. Of these patients, 120 met our inclusion criteria. Logistic regression analysis was used to examine the relationship between predictability of positive findings and patients’ characteristics, such as prostate-specific antigen (PSA) level at the time of scan, PSA kinetics, Gleason score, staging, and type of treatment before scan. Results In total, 68.3% of the 120 11C-acetate PET/CTAC scans were positive. The percentage of positive scans and PSA at the time of scanning and PSA velocity (PSAV) had positive correlations. The putative sensitivity and specificity were 86.6% and 65.8%, respectively, when a PSA level greater than 1.24 ng/mL was used as the threshold for scanning. The putative sensitivity and specificity were 74% and 75%, respectively, when a PSAV level greater than 1.32 ng/mL/y was used as the threshold. No significant associations were found between scan positivity and age, PSA doubling time, Gleason score, staging, or type of treatment before scanning. Conclusions This retrospective study suggests that threshold models of PSA greater than 1.24 ng/mL or PSAV greater than 1.32 ng/mL per year are independent predictors of positive findings in 11C-acetate PET/CTAC imaging of recurrent prostate cancer.

This case report describes false-positive positron-emission tomography/computed tomography (PET/CT) findings related to oral prostheses and its implications in cancer surveillance. In head and neck cancer management, F18-flurodeoxyglucose (FDG) PET/CT is widely accepted for evaluating treatment response and detecting recurrence. Interpretation of FDG PET/CT images in this setting is often challenging due to various prostheses and reconstruction methods. Following surgery for squamous cell carcinoma of the maxillary alveolus, a 61-year-old female had a FDG PET/CT scan on a 7-month follow-up that showed high FDG uptake along the resection site. Clinical examination showed no signs of inflammation or recurrence. Repeat FDG PET/CT without the prosthesis was normal. The PET/CT attenuation-corrected images demonstrated high FDG uptake (standardized uptake value: 11.6) along the resection site corresponding to contrast-enhanced CT images of the lesion. PET/CT nonattenuation-corrected images also confirmed increased activity. Repeat PET/CT without the prosthesis was normal. FDG is not tumor specific; it can accumulate in inflammation, infection, and post-therapy settings. Metallic and high-density prostheses show radial artifacts on CT and falsely elevated FDG uptake on PET/ CT in adjacent areas. Salivary pooling may concentrate FDG. The presence of oral prostheses has not been described as a cause of this high level of activity. PET/CT images that demonstrate intense activity corresponding to dense structures should be viewed with caution. A detailed history and physical exam as well as knowledge of artifacts are pertinent for the managing physician. Laryngoscope, 2012

Malignancy after solid organ or stem cell transplant can occur in three distinct ways: de novo, recurrent in the recipient, or transmission from donor to recipient [1]. According to an Organ Procur...

This article provides an overview of imaging modalities that aid in diagnosing, staging, and assessing therapeutic response in prostate cancer. Prostate cancer is the second most common type of cancer in American men and the second leading cause of cancer death among men. Prostate cancer is difficult to diagnose in early stages, and advanced disease often recurs after treatment. To localize sites of recurrence many imaging modalities have been used with varying success. This article presents case studies of PET scanning using carbon 11 acetate and discusses intravenously infused ascorbate, a complementary and alternative medicine therapy for prostate cancer.

Background Gastric Emptying Scintigraphy (GES) at intervals over 4 hours after a standardized radio-labeled meal is commonly regarded as the gold standard for diagnosing gastroparesis. The objectives of this study were: 1) to investigate the best time point and the best combination of multiple time points for diagnosing gastroparesis with repeated GES measures, and 2) to contrast and cross-validate Fisher's Linear Discriminant Analysis (LDA), a rank based Distribution Free (DF) approach, and the Classification And Regression Tree (CART) model. Methods A total of 320 patients with GES measures at 1, 2, 3, and 4 hour (h) after a standard meal using a standardized method were retrospectively collected. Area under the Receiver Operating Characteristic (ROC) curve and the rate of false classification through jackknife cross-validation were used for model comparison. Results Due to strong correlation and an abnormality in data distribution, no substantial improvement in diagnostic power was found with the best linear combination by LDA approach even with data transformation. With DF method, the linear combination of 4-h and 3-h increased the Area Under the Curve (AUC) and decreased the number of false classifications (0.87; 15.0%) over individual time points (0.83, 0.82; 15.6%, 25.3%, for 4-h and 3-h, respectively) at a higher sensitivity level (sensitivity = 0.9). The CART model using 4 hourly GES measurements along with patient's age was the most accurate diagnostic tool (AUC = 0.88, false classification = 13.8%). Patients having a 4-h gastric retention value >10% were 5 times more likely to have gastroparesis (179/207 = 86.5%) than those with ≤10% (18/113 = 15.9%). Conclusions With a mixed group of patients either referred with suspected gastroparesis or investigated for other reasons, the CART model is more robust than the LDA and DF approaches, capable of accommodating covariate effects and can be generalized for cross institutional applications, but could be unstable if sample size is limited.

A 68-year-old white female presented with two years of progressively worsening dyspnea. Echocardiography revealed a large right atrial mass and partial obstruction of the inferior vena cava. Further imaging revealed a cystic dense mass in the inferior vena cava and right atrium. Immunohistochemical stains were consistent with leiomyosarcoma. Intraoperatively, the tumor was noted to originate from the posterior aspect of the inferior vena cava. The patient underwent successful resection of the mass. Adjuvant radiation therapy was completed. The patient's dyspnea gradually improved and she continues to remain disease free five years post-resection.

Background Many studies assessed gastric retention over time utilizing different models, mostly with scintigraphic measures at varied endpoints from limited number of normal volunteers. With a standardized 4-h gastric emptying (GE) protocol, we compared model fit by the linear, power exponential (PE), and modified power exponential (MPE) models to contrast differences in GE among different groups based on clinical diagnosis and gender. Methods We retrospectively collected 320 patient records with four consecutive hourly scintigraphic measures of percent intragastric residual at the Kansas University Medical Center. We obtained parameter estimates with the Bayesian hierarchical models using informative priors from previous research. Key Results The PE or MPE model captured the time dependent GE rate better than the linear model. The estimated GE rates more than doubled for those without gastroparesis compared to patients diagnosed with gastroparesis. Males tended to empty gastric content faster but were not significantly different from females at the 5% level. Conclusions & Inferences The point estimates and 95% credible interval for GE rates obtained with the PE and MPE models may provide an alternative diagnostic tool for clinicians since it utilizes gastric emptying scintigraphy measures at multiple endpoints which may be sensitive to different aspects of the disease. No agreement in lag phases was obtained by the three models based on respective definitions from previous researches, but similar results would be obtained with the PE and MPE models if both defined lag phase by back projecting the regression lines to the same gastric retention level.

Objectives: The role of positron emission tomography (PET) with fluoro-deoxy-glucose (FDG) in the staging of head and neck cancer (HNC) is unclear. The NCCN guidelines do not recommend FDG-PET as a part of standard workup. The purpose of this report is to examine the role of FDG-PET imaging in altering management and providing prognostic information for HNC.Methods: Retrospective review of HNC patients who had a staging FDG-PET scan performed at either Thomas Jefferson University or University of Kansas Medical Center between the years 2001 and 2007. A total of 212 PET scans were performed in patients who went on to receive radiotherapy.Results: The median follow-up time for all patients was 469 days. The PPV and NPV of PET imaging to correctly identify lymph node status was 94% and 89% respectively. Lymph nodes with extracapsular extension (ECE) had higher SUVs than nodes without ECE, 11.0 vs. 5.0 (p < 0.0007). Maximum SUV for the primary tumor > 8.0 was predictive of worse overall survival (p < 0.045), while the SUV of the lymph nodes was predictive for distant recurrence at one year-with a mean SUV value of 10.4 for patients with distant failure vs. 7.0 without (p < 0.05).Conclusions: FDG-PET staging in head and neck cancer has good positive and negative predictive values in determining lymph node status. The maximum SUV of the primary tumor is predictive of overall survival. This is the first report to find that the SUV of a lymph node is predictive for ECE and also for distant recurrence.

The aims were to investigate the effects of gastric electrical stimulation (GES) on autonomic function, gastric distention and tone, and central control mechanisms in gastroparetic patients. Ten gastroparetic patients refractory to standard medical therapy participated in this study and data were collected at baseline, within two weeks before surgery for implantation of GES system, and at follow-up sessions between 6 and 12 weeks after GES therapy was initiated. In each session, electrocardiogram, electrogastrogram (EGG) and gastric barostat measurements were conducted before and after a caloric liquid meal. Positron Emission Tomography (PET) brain scans were performed on a separate day. During GES therapy there was a significant increase in the discomfort threshold for mean pressure from 21 mmHg at baseline to 25 mmHg at follow-up, and for mean volume from 561 mL to 713 mL. A significant increase in the postprandial EGG power (amplitude) was observed between baseline and follow up. The sympathovagal balance was significantly decreased after GES therapy, indicating a significant increase in vagal activity. The cumulative PET data showed an increase in quantitative radioactive counts relative to the standardized data base in both the thalamic and caudate nuclei after chronic GES therapy. We conclude that our data suggest that the symptomatic improvement achieved by GES in gastroparesis is best explained by activation of vagal afferent pathways to influence CNS control mechanisms for nausea and vomiting accompanied by enhanced vagal efferent autonomic function and decreased gastric sensitivity to volume distention which enhances postprandial gastric accommodation.

The role of positron emission tomography with CT attenuation correction (PET) scanning in the staging of head and neck cancer (HNC) is unclear. The NCCN guidelines do not recommend PET as a routine of standard workup, and the extent to which PET scan changes management is not as well documented as compared to other cancer sites. The purpose of this report is to examine the role of FDG-PET imaging in altering management and providing prognostic information for HNC. Retrospective review of HNC patients who had a staging PET scan performed at either Thomas Jefferson University or University of Kansas Medical Center between the years 2001 and 2007. A total of 274 PET scans were reviewed; 213 PET scans in patients who went on to receive definitive radiotherapy. One hundred ten patients had a neck dissection after the PET scan was performed for evaluation of lymph node status. The median follow-up time for the 213 patients undergoing definitive radiation was 469 days, with 79 recurrences (44 local, 35 distant). Ten of 183 (6%) patients who were clinically M0 (ie, negative clinical exam and CXR) had metastatic disease diagnosed on the staging PET scan with 1 false negative and 12 false positives for a PPV of 33.3% and NPV of 99.5%. In the 110 patients with a post-PET neck dissection, the PPV and NPV for PET scans in determining lymph node status was 94% and 89%, respectively. The median standard uptake value (SUV) for the tumor mass and lymph nodes were evaluated in 160 patients. Patients with extracapsular extension (ECE) of the lymph node had a higher lymph node SUV versus patients negative for ECE (11.5 vs 6.3, p = 0.0002). SUV values of the tumor mass or lymph nodes were not predictive for overall or local recurrence, but SUV of the lymph node was predictive for distant recurrence at 1 year with median SUV values of 10.4 for patients with distant failure vs 7.0 without (p = 0.0495). PET scans are a valuable tool in staging HNC. PET scans have good accuracy and predictive value in determining lymph node status. SUV of the lymph node is predictive for ECE and also for distant recurrence. This has treatment implications in that patients with higher lymph node SUVs receiving definitive radiation may warrant higher doses for treatment of the more aggressive ECE. Also, since lymph node SUV is predictive for distant recurrence, this can allow stratification for patients who would be more likely to benefit from induction chemotherapy.

From the Departments of *Hematology, †Medicine, and ‡Radiology and Nuclear Medicine, University of Kansas Medical Center, Kansas City, KS. Reprints: Siddhartha Ganguly, MD, University of Kansas Medical Center, Department of Hematology, MS 4038, 3901 Rainbow Blvd., Kansas City, KS 66160. E-mail: [email protected].

558 Background: Integrated FDG-PET/CT improves the diagnostic accuracy of staging of some cancers. The value of FDG-PET/CT in initial staging of breast cancer for detection of distant metastases has not been defined. Methods: Retrospective analysis of 83 consecutive women at the University of Kansas Medical Center who had a FDG-PET/CT from Jan 2005 to July 2006, at the time of initial diagnosis of invasive breast cancer. Women with symptoms suspicious for metastatic disease were excluded. Radiographic reports and patient charts were reviewed. All suspicious CT scans were re-read by a single radiologist who was blinded to the PET results. All suspicious scans were confirmed either by a biopsy or follow-up scans according to the discretion of the treating physician. Results: Median age was 52. 23 (28%) cancers were stage I, 44 (53%) stage II and 16 (19%) were stage III. 15/83 (18%) women had a suspicious FDG-PET/CT. Only 2 of these 15 women were confirmed to have metastatic disease, while 13 (16 %) had a false positive (FP) scan. In 5 women where both CT and PET were suspicious, 2 were true positives (TP) whereas 3 were FP. All 3 women who had suspicious PET but a non-suspicious CT were FP. All 7 women who had a non-suspicious PET and a suspicious CT were FP. PET influenced the CT classification by the radiologist in 5 (6%) women. 71/83 (86%) women had a negative or a non-suspicious CT. 3 women had lesions classified as non-suspicious with the help of a negative PET, two had lesions classified as suspicious with the help of a positive PET and seven had suspicious lesions on CT regardless of the PET. FDG-PET/CT resulted in unnecessary follow-up scans in eleven women, and unnecessary biopsies in two. One TP had metastatic bone disease. The other TP had a solitary liver metastasis detected by FDG-PET/CT which was resected and she has no evidence of disease after two years of follow-up. Conclusions: Given the high false positive rate and overall low incidence of metastases, routine use of FDG- PET/CT in asymptomatic women diagnosed with invasive breast cancer cannot be recommended. No significant financial relationships to disclose.