Induction versus no induction chemotherapy before neoadjuvant chemoradiotherapy and surgery in oesophageal adenocarcinoma: a multicentre randomised phase II trial (NCCTG N0849 [Alliance])

AIM

report primary results from the first multicentre randomised trial evaluating induction chemotherapy prior to trimodality therapy in patients with oesophageal or gastro-oesophageal junction adenocarcinoma. Notably, recent data from a single-institution randomised trial reported that induction chemotherapy prolonged overall survival (OS) in patients with well/moderately differentiated tumours.

METHODS

In this phase 2 trial (28 centres in the U.S. NCI-sponsored North Central Cancer Treatment Group [Alliance]), trimodality-eligible patients (T3-4N0, TanyN+) were randomised to receive induction (docetaxel, oxaliplatin, capecitabine; Arm A) or no induction chemotherapy (Arm B) followed by oxaliplatin/5-fluorouracil/radiation and subsequent surgery. The primary endpoint was the rate of pathologic complete response (pathCR). Secondary/exploratory endpoints were OS and disease-free survival (DFS).

RESULTS

Of 55 patients evaluable for the primary endpoint, the pathCR rate was 28.6% (8/28) in A versus 40.7% (11/27) in B (P = .34). Given interim results indicating futility, accrual was terminated, but patients were followed. After a median follow-up of 60.4 months, a longer median OS in Arm A versus B was unexpectedly observed (3-year rates 57.1% versus 41.7%, respectively) driven by longer DFS after margin-free surgery. In posthoc analysis, induction (versus no induction) chemotherapy was associated with significantly longer OS and DFS among patients with well/moderately differentiated tumours, but not among patients with poorly/undifferentiated tumours (Pinteraction = 0.037).

CONCLUSIONS

Adding induction chemotherapy prior to trimodality therapy did not improve the primary endpoint, pathCR. However, induction chemotherapy was associated with longer median OS, particularly among patients with well/moderately differentiated tumours. These findings may inform further development of curative-intent trials in this disease.

The flip-flop fungus sign: an FDG PET/CT sign of benignity

Benign granulomatous processes such as fungal infection may mimic metastatic lung cancer on FDG PET/CT. We found that these processes often have draining lymph node(s) with equal or greater FDG activity than associated lung nodule(s), a "flip-flop" of what is commonly seen in lung cancer. The aim of this study was to examine the utility of this "flip-flop fungus" (FFF) sign for diagnosing benign pulmonary disease. FDG PET/CT scans performed between 9/09-3/13 for the indications of pulmonary nodule or mass were reviewed. Scans with at least one hilar or mediastinal FDG avid draining node were included. Patients with a history of cancer, lack of pathologic confirmation, or without at least two years of imaging follow-up were excluded. A total of 209 FDG PET/CT exams were included and reviewed in a blinded fashion. A positive FFF sign had a sensitivity of 60.0% (95% CI: 47.6-71.5%) and specificity of 84.9% (95% CI: 77.8-90.4%) (P<0.0001) for benign disease. With additional strict imaging criteria applied, the FFF sign had a specificity of 98.6% (95% CI: 94.9-99.8%) (P<0.0001) and a positive predictive value of 90.0% (95% CI: 68.3-98.5%). A positive FFF sign was predominately due to granulomatous disease (91%), mostly histoplasmosis (73%). A positive FFF sign combined with positive fungal serology (n=16) had a specificity of 100% for benign disease. The FFF sign predicts benign disease in patients with a lung nodule(s) and an FDG avid draining lymph node(s) that would otherwise be considered worrisome for cancer.

Spectrum of Benign Articular and Periarticular Findings at FDG PET/CT

Whole-body fluorine 18 fluorodeoxyglucose (FDG) positron-emission tomography (PET)/computed tomography (CT) is performed primarily for oncologic indications; however, FDG uptake is not specific for malignancy. Herein we focus on causes of increased FDG uptake in and around joints, as lesions in these locations are commonly benign. A combination of primary intra-articular processes and osseous processes that may occur near the joint space will be discussed. Causes of intra-articular and periarticular increased FDG activity can be broadly divided into infectious, inflammatory, degenerative, and benign neoplastic categories. A familiarity with the full range of these processes is important to avoid misinterpretation, in turn decreasing unnecessary follow-up studies, procedures, and treatments. Differentiation from malignancy is often possible on the basis of a different level of FDG activity, divergent response to therapy, or differing changes over time, in comparison with a patient's known primary cancer. Recognizing an intra-articular lesion location can also be critical, as intra-articular metastases are rare. In some cases, benign FDG-avid articular and periarticular entities have a specific appearance at FDG PET/CT and a correct diagnosis may be made without any additional workup. In most other cases, comparison with prior studies and/or additional imaging can afford an accurate diagnosis. This review is meant to introduce the reader to a spectrum of benign FDG-avid articular and periarticular processes that may be encountered at oncologic FDG PET/CT to increase confidence and diagnostic accuracy. (©)RSNA, 2016.

¹¹C-Choline PET/CT in Recurrent Prostate Cancer and Nonprostatic Neoplastic Processes

Choline positron emission tomography (PET)/computed tomography (CT), with both carbon 11 ((11)C) choline and fluorine 18 ((18)F) choline, is an increasingly used tool in the evaluation of patients with biochemically recurrent prostate cancer. It has allowed detection and localization of locally recurrent and metastatic lesions that were difficult or impossible to identify using more conventional modalities. Many of the patients followed for their prostate cancer are elderly and have a higher rate of nonprostate cancer lesions or malignancies. As our experience with choline PET/CT has grown, it has become apparent that many of these nonprostate cancer processes, both benign and malignant, can be detected. Invasive thymoma, renal cell carcinoma, papillary thyroid carcinoma, and parathyroid adenoma are a few of the processes that have been incidentally detected with (11)C-choline PET/CT at our institution and have significantly altered subsequent clinical management of the patient. Although most of the secondary lesions are detected due to their increased (11)C-choline avidity, several have been detected due to their decreased or lack of avidity in the background of a highly avid organ. For instance, large liver masses that are relatively non-choline-avid create large activity defects in the otherwise highly active liver. Familiarity with normal (11)C-choline physiologic activity, the most common prostate metastatic patterns, and imaging characteristics of secondary lesions is essential for the detection and correct diagnosis of such lesions so that proper follow-up and management can be recommended.

MR imaging and PET/CT in diagnosis and management of multiple myeloma

Multiple myeloma is a common hematologic malignancy among the elderly population. Although there have been many advances in treatment over the past few decades, the overall prognosis for the disease remains poor. Conventional radiography has long been the standard of reference for the imaging of multiple myeloma. However, 10%-20% of patients with multiple myeloma do not have evidence of disease at conventional radiography. There is a growing body of evidence supporting use of magnetic resonance (MR) imaging and 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) in diagnosis and management of multiple myeloma. MR imaging is useful in detection of bone marrow infiltration, a finding often missed at conventional radiography. FDG PET/CT is especially sensitive for the detection of extramedullary disease and can help detect the metabolically active lesions that often precede evidence of osseous destruction at conventional radiography. MR imaging and FDG PET/CT are useful tools that can provide essential information for diagnosis and management of patients with multiple myeloma. Both modalities allow accurate localization of disease after chemotherapy or autologous stem cell transplantation and can provide important prognostic information that can influence further clinical decision making regarding therapy, particularly when tumor serum markers may be a less reliable indicator of disease burden after repeated treatments.

Structural and functional imaging in parkinsonian syndromes

Movement disorders with parkinsonian features are common, and in recent years imaging has assumed a greater role in diagnosis and management. Thus, it is important that radiologists become familiar with the most common imaging patterns of parkinsonism, especially given the significant clinical overlap and diagnostic difficulty associated with these disorders. The authors review the most common magnetic resonance (MR) and molecular imaging patterns of idiopathic Parkinson disease and atypical parkinsonian syndromes. They also discuss the interpretation of clinically available molecular imaging studies, including assessment of cerebral metabolism with 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET), cortical amyloid deposition with carbon 11 ((11)C) Pittsburgh compound B and fluorine 18 ((18)F) florbetapir PET, and dopaminergic activity with iodine 123 ((123)I) ioflupane single photon emission computed tomography (SPECT). Although no single imaging test is diagnostic, a combination of tests may help narrow the differential diagnosis. Findings at (123)I ioflupane SPECT can confirm the loss of dopaminergic neurons in patients with parkinsonism and help distinguish these syndromes from treatable conditions, including essential tremor and drug-induced parkinsonism. FDG PET uptake can demonstrate patterns of neuronal dysfunction that are specific to a particular parkinsonian syndrome. Although MR imaging findings are typically nonspecific in parkinsonian syndromes, classic patterns of T2 signal change can be seen in multiple system atrophy and progressive supranuclear palsy. Finally, positive amyloid-binding PET findings can support the diagnosis of dementia with Lewy bodies. Combined with a thorough clinical evaluation, multimodality imaging information can afford accurate diagnosis, allow selection of appropriate therapy, and provide important prognostic information.

Future of thoracic PET scanning

The advances in PET scanning for thoracic diseases that are deemed most likely to have clinical impact in the near-term future are highlighted in this article. We predict that the current practice of medicine will continue to embrace the power of molecular imaging and specifically PET scanning. 18F-fluorodeoxyglucose-PET scanning will continue to evolve and will expand into imaging of inflammatory disorders. New clinically available PET scan radiotracers, such as PET scan versions of octreotide and amyloid imaging agents, will expand PET imaging into different disease processes. Major improvements in thoracic PET/CT imaging technology will become available, including fully digital silicone photomultipliers and Bayesian penalized likelihood image reconstruction. These will result in significant improvements in image quality, improving the evaluation of smaller lung nodules and metastases and allowing better prediction of prognosis. The birth of clinical PET/MRI scan will add new imaging opportunities, such as better PET imaging of pleural diseases currently obscured by complex patient motion.

Multiple myeloma

This article presents a review of multiple myeloma, precursor states, and related plasma cell disorders. The clinical roles of fluorodeoxyglucose PET/computed tomography (CT) and the potential to improve the management of patients with multiple myeloma are discussed. The clinical and research data supporting the utility of PET/CT use in evaluating myeloma and other plasma cell dyscrasias continues to grow.

A phase II trial of everolimus, temozolomide, and radiotherapy in patients with newly diagnosed glioblastoma: NCCTG N057K

BACKGROUND

The mammalian target of rapamycin (mTOR) functions within the phosphatidylinositol-3 kinase (PI3K)/Akt pathway as a critical modulator of cell survival. This clinical trial evaluated the combination of the mTOR inhibitor everolimus with conventional temozolomide (TMZ)-based chemoradiotherapy.

METHODS

Newly diagnosed patients with glioblastoma multiforme were eligible for this single arm, phase II study. Everolimus (70 mg/wk) was started 1 week prior to radiation and TMZ, followed by adjuvant TMZ, and continued until disease progression. The primary endpoint was overall survival at 12 months, and secondary endpoints were toxicity and time to progression. Eleven patients were imaged with 3'-deoxy-3'-(18)F-fluorothymidine ((18)FLT)-PET/CT before and after the initial 2 doses of everolimus before initiating radiation/TMZ. Imaged patients with sufficient tumor samples also underwent immunohistochemical and focused exon sequencing analysis.

RESULTS

This study accrued 100 evaluable patients. Fourteen percent of patients had grade 4 hematologic toxicities. Twelve percent had at least one grade 4 nonhematologic toxicity, and there was one treatment-related death. Overall survival at 12 months was 64% and median time to progression was 6.4 months. Of the patients who had (18)FLT-PET data, 4/9 had a partial response after 2 doses of everolimus. Focused exon sequencing demonstrated that (18)FLT-PET responders were less likely to have alterations within the PI3K/Akt/mTOR or tuberous sclerosis complex/neurofibromatosis type 1 pathway compared with nonresponders.

CONCLUSION

Combining everolimus with conventional chemoradiation had moderate toxicity. (18)FLT-PET studies suggested an initial antiproliferative effect in a genetically distinct subset of tumors, but this did not translate into an appreciable survival benefit compared with historical controls treated with conventional therapy.

Dopamine Transporter SPECT Imaging in Parkinson Disease and Dementia

The clinical diagnosis of Parkinson disease (PD) is difficult, as several other neurodegenerative and basal ganglia disorders have similar clinical presentations. Dopamine transporter single-photon emission computed tomography has been proposed as possible diagnostic tool to help differentiate idiopathic PD from essential tremor and other disorders that present with parkinsonian symptoms. In addition, it is valuable in the diagnosis of dementia with Lewy bodies, differentiating it from other causes of dementia such as Alzheimer disease.

Role of positron emission tomography/computed tomography in bone malignancies

This article presents an overview of positron emission tomography combined with computed tomography (PET/CT) imaging of bone tumors for the practicing radiologist. The clinical roles and utility of (18)F-labeled fluorodeoxyglucose PET/CT in patients with primary bone tumors, osseous metastases, and multiple myeloma are reviewed. The clinical and research data supporting the utility of PET/CT in the evaluation of skeletal malignancies continues to grow.

Randomized phase II trial of extended versus standard neoadjuvant therapy for esophageal cancer, NCCTG (Alliance) trial N0849

4026

Background: Patients (pts) with locally advanced esophageal or gastroesophageal junction (GEJ) adenocarcinoma commonly receive neoadjuvant chemoradiotherapy (chemo-RT). Despite this approach the rate of recurrence remains high. Given the difficulties of postoperative therapy, the efficacy of extended neoadjuvant therapy was assessed. Methods: Eligibility criteria included T3-4,N0 – Tany,N(+) disease amenable to radiation and surgery. Pts were randomized to either arm A (docetaxel 60 mg/m2 day 1 , oxaliplatin [Oxal] 85 mg/m2 day 1, and capecitabine 1250 mg/m2/day days 1-14 x 2 cycles [DOC] followed by 5-FU 180 mg/m2/day continuous IV through radiation + Oxal 85 mg/m2 days 1,15,29 + 50.4 Gy radiation (chemo-RT)) or arm B (chemo-RT alone). Randomization was stratified by ECOG PS (0/1 vs 2) and stage (II vs III/IVA). Primary endpoint was pathologic complete response (PCR) rate, defined as no gross or microscopic tumor identified in the surgical specimen. Interim analysis assessed efficacy and futility of the experimental intervention. Wilcoxon rank sum and Fisher’s exact tests were used to compare clinical/pathologic factors between arms. Results: Baseline and stratification factors were well balanced between arms. Of 42 pts included in the interim analysis (86% male; age [median 63, range 38-88], 100% PS 0/1; 71% stage III; 55% esophagus, 40% GEJ; 36% measurable disease), 4 and 1 pts in arms A and B, respectively, did not have surgery due to death (A, 2), progressive disease (A, 1), alternative treatment (A, 1) or adverse event (B, 1). Among 21 arm A pts, 21, 20, and 19 pts started 1st cycle of DOC, 2nd cycle of DOC and chemo-RT, respectively. All arm B pts received chemo-RT. 33% (7/21) of arm A and 48% (10/21) of arm B pts achieved PCR (p=0.53). Among pts undergoing surgery, 94% (16/17) and 100% (20/20) of arm A and B pts had complete resection (p=0.46). 38% and 24% of arm A and B pts experienced at least one grade 4+ adverse event at least possibly related to treatment (p=0.51). Conclusions: Extended neoadjuvant therapy in pts with locally advanced esophageal or GEJ adenocarcinoma failed to improve the PCR rate. Follow-up in regard to survival and rate of recurrence is ongoing. Clinical trial information: NCT00938470.

Application of the National Institute on Aging-Alzheimer's Association AD criteria to ADNI

OBJECTIVE

We describe the operationalization of the National Institute on Aging-Alzheimer's Association (NIA-AA) workgroup diagnostic guidelines pertaining to Alzheimer disease (AD) dementia in a large multicenter group of subjects with AD dementia.

METHODS

Subjects with AD dementia from the Alzheimer's Disease Neuroimaging Initiative (ADNI) with at least 1 amyloid biomarker (n = 211) were included in this report. Biomarker data from CSF Aβ42, amyloid PET, fluorodeoxyglucose-PET, and MRI were examined. The biomarker results were assessed on a per-patient basis and the subject categorization as defined in the NIA-AA workgroup guidelines was determined.

RESULTS

When using a requirement that subjects have a positive amyloid biomarker and single neuronal injury marker having an AD pattern, 87% (48% for both neuronal injury biomarkers) of the subjects could be categorized as "high probability" for AD. Amyloid status of the combined Pittsburgh compound B-PET and CSF results showed an amyloid-negative rate of 10% in the AD group. In the ADNI AD group, 5 of 92 subjects fit the category "dementia unlikely due to AD" when at least one neuronal injury marker was negative.

CONCLUSIONS

A large proportion of subjects with AD dementia in ADNI may be categorized more definitively as high-probability AD using the proposed biomarker scheme in the NIA-AA criteria. A minority of subjects may be excluded from the diagnosis of AD by using biomarkers in clinically categorized AD subjects. In a well-defined AD dementia population, significant biomarker inconsistency can be seen on a per-patient basis.

The added value of 18F-FDG PET/CT for evaluation of patients with esthesioneuroblastoma

The purpose of this study was to evaluate the clinical utility of (18)F-FDG PET/CT in esthesioneuroblastoma staging and restaging and quantify the additional benefit of PET/CT to conventional imaging.

METHODS

A retrospective review was performed with institutional review board approval for patients with a diagnosis of esthesioneuroblastoma who underwent PET/CT from 2000 to 2010. PET/CT results were retrospectively reviewed by 2 radiologists who were unaware of the clinical and imaging data. Positive imaging findings were classified into 3 categories: local disease, cervical nodal spread, and distant metastasis. All conventional imaging performed in the 6 mo preceding PET/CT, and the medical records, were reviewed to determine the potential added value.

RESULTS

Twenty-eight patients (mean age, 52.3 ± 10 y; range, 23-81 y) were identified who underwent a total of 77 PET/CT examinations. Maximum standardized uptake value (SUVmax) was 8.68 ± 4.75 (range, 3.6-23.3) for the primary tumor and 8.57 ± 6.46 (range, 1.9-27.2) for the metastatic site. There was no clear association between primary tumor SUVmax and tumor grade (P = 0.30). Compared with conventional imaging, PET/CT changed disease stage or altered clinical management in 11 (39%) of 28 esthesioneuroblastoma patients. Of these, 10 (36%) of 28 were upstaged on the basis of their PET/CT studies. Cervical nodal metastases were found in 5 (18%) of 28, local recurrence in 2 (7%) of 28, cervical nodal and distant metastases in 2 (7%) of 28, and distant metastases in 1 (4%) of 28. One patient (4%) was downstaged after negative findings on PET/CT.

CONCLUSION

PET/CT is a useful adjunct to conventional imaging in the initial staging and restaging of esthesioneuroblastoma by detecting nodal and distant metastatic disease not demonstrated by conventional imaging and identifying local recurrence hidden by treatment changes on conventional imaging.

NCCTG N057K phase II trial of everolimus, temozolomide, and radiotherapy in patients with newly diagnosed glioblastoma: A North Central Cancer Treatment Group trial

2031

Background: The mammalian target of rapamycin (mTOR) functions within the PI3K/Akt pathway as a critical modulator of cell survival. Preclinical studies in GBM indicate that the combination of mTOR inhibitors, such as everolimus (RAD001), with either radiation therapy (RT) or temozolomide (TMZ) provide increased tumor cell killing. Methods: Newly diagnosed GBM pts were eligible for the study. RAD001 was dosed orally at 70 mg/week weekly, starting 1 week prior to RT/TMZ, and continued throughout RT/TMZ, adjuvant TMZ and then until progression. This was a single arm phase II design powered to detect a true overall survival at 12 months (OS12) of 73% (vs 58% in historical controls). Secondary endpoints were toxicity, response rate, and time to progression (TTP). A subgroup of patients with measurable residual disease were eligible for the PET imaging component of the study, consisting of an 18FLT-PET/CT scan performed before and after the initial two doses of RAD001 but before the first dose of RT or TMZ. Results: 103 patients were accrued to phase II of which 100 were evaluable. The median age was 60.5 years (23-81), median ECOG PS was 1, 46 patients had GTR, 33 STR, and the remainder had biopsy at diagnosis. Treatment tolerance was acceptable: 17% patient had at least one grade 3 hematologic toxicity; 14% had at least one grade 4 hematologic toxicity, 42% had at least one grade 3 non-heme toxicity, while 12% had at least one grade 4 non-heme toxicity. No increased incidence of infectious complications was observed and there were no treatment related deaths. Median PFS was 5.3 months (1.3-21.4), with 22 patients progression free. Mature OS data will be available at the meeting. MGMT methylation status analysis is ongoing. Of the pts who had evaluable FLT-PET data, three of eight (37.5%) had a drop in SUVmax >25% after two treatments of RAD001. Conclusions: RAD001 with standard of care chemoradiation had moderate toxicity. Serial 18FLT-PET was feasible for evaluating drug-induced changes in tumor proliferation following RAD001. Final outcome data and association of MGMT status with outcome will be reported at the meeting.

Amyloid and glucose imaging in dementia with Lewy bodies and multiple systems atrophy

BACKGROUND

Multiple Systems Atrophy (MSA) and Dementia with Lewy bodies (DLB) can present with both REM behavior disorder and severe autonomic dysfunction. In rare occasions, patients with MSA progress to cognitive impairment and even dementia. Positron emission topography (PET) imaging using both the amyloid ligand Pittsburgh Compound B (11C-PiB) and 18 flurodeoxyglucose (18F-FDG) was used to ascertain the presence of amyloid and pattern of glucose metabolic derangement in both disorders.

METHODS

Patients diagnosed with probable DLB or MSA, with clinical symptoms of either REM Behavior Disorder (RBD), Parkinsonism, or dysautonomia were prospectively identified. All underwent both 11C-PiB and 18F-FDG PET imaging. Statistical comparison between DLB, MSA, and normal controls was performed.

RESULTS

Six patients, 3 with DLB, 2 with Parkinson predominant MSA (MSA-P), and 1 with cerebellar predominant MSA (MSA-C) were identified. Increased level of PiB retention was noted in all patients diagnosed with DLB, but was absent in MSA. In those with DLB, glucose hypometabolism corresponded with regions of amyloid presence, and included prefrontal, parietotemporal, occipital and primary visual cortex regions. MSA patients were distinguished by cerebellar glucose hypometabolism.

CONCLUSIONS

These findings emphasize the distinguishing characteristics between the alpha-synuclein related disorders of DLB and MSA. The absence of amyloid in the cases of MSA is a possible distinguishing characteristic of the disorder.

North Central Cancer Treatment Group Phase I trial N057K of everolimus (RAD001) and temozolomide in combination with radiation therapy in patients with newly diagnosed glioblastoma multiforme

BACKGROUND

The mammalian target of rapamycin (mTOR) functions within the PI3K/Akt signaling pathway as a critical modulator of cell survival. On the basis of promising preclinical data, the safety and tolerability of therapy with the mTOR inhibitor RAD001 in combination with radiation (RT) and temozolomide (TMZ) was evaluated in this Phase I study.

METHODS AND MATERIALS

All patients received weekly oral RAD001 in combination with standard chemoradiotherapy, followed by RAD001 in combination with standard adjuvant temozolomide. RAD001 was dose escalated in cohorts of 6 patients. Dose-limiting toxicities were defined during RAD001 combination therapy with TMZ/RT.

RESULTS

Eighteen patients were enrolled, with a median follow-up of 8.4 months. Combined therapy was well tolerated at all dose levels, with 1 patient on each dose level experiencing a dose-limiting toxicity: Grade 3 fatigue, Grade 4 hematologic toxicity, and Grade 4 liver dysfunction. Throughout therapy, there were no Grade 5 events, 3 patients experienced Grade 4 toxicities, and 6 patients had Grade 3 toxicities attributable to treatment. On the basis of these results, the recommended Phase II dosage currently being tested is RAD001 70 mg/week in combination with standard chemoradiotherapy. Fluorodeoxyglucose (FDG) positron emission tomography scans also were obtained at baseline and after the second RAD001 dose before the initiation of TMZ/RT; the change in FDG uptake between scans was calculated for each patient. Fourteen patients had stable metabolic disease, and 4 patients had a partial metabolic response.

CONCLUSIONS

RAD001 in combination with RT/TMZ and adjuvant TMZ was reasonably well tolerated. Changes in tumor metabolism can be detected by FDG positron emission tomography in a subset of patients within days of initiating RAD001 therapy.

Fluorodeoxyglucose F18 positron emission tomography in progressive apraxia of speech and primary progressive aphasia variants

OBJECTIVES

To determine patterns of hypometabolism on fluorodeoxyglucose F18 positron emission tomography (FDG-PET) in patients with progressive apraxia of speech (PAS) and primary progressive aphasia (PPA) variants and to use these patterns to further refine current classification.

DESIGN

We identified all patients who had FDG-PET and PAS or PPA who were evaluated by an expert speech-language pathologist. Patterns of hypometabolism were independently classified by 2 raters blinded to clinical data. Three speech-language pathologists reclassified all patients into 1 of 7 operationally defined categories of PAS and PPA blinded to FDG-PET data.

SETTING

Tertiary care medical center.

PATIENTS

Twenty-four patients with PAS or PPA and FDG-PET.

MAIN OUTCOME MEASURE

Fluorodeoxyglucose F18 PET hypometabolic pattern.

RESULTS

Of the 24 patients in the study, 9 had nonfluent speech output; 14, fluent speech; and 1 was unclassifiable. Twenty-one patients showed FDG hypometabolism; the remaining 3 did not. Among the patients showing hypometabolism, 8 had a prerolandic pattern of which 7 had nonfluent speech including progressive nonfluent aphasia (n = 3), PAS (n = 1), and mixed nonfluent aphasia/apraxia of speech (n = 3); the other patient had PPA unclassifiable. The remaining 13 had a postrolandic pattern, all with fluent speech (P < .001), including logopenic progressive aphasia (n = 6), progressive fluent aphasia (n = 6), and semantic dementia (n = 1). Patterns of hypometabolism differed between the nonfluent variants and between the fluent variants, including progressive fluent aphasia.

CONCLUSION

Patterns of FDG-PET hypometabolism support the clinical categorizations of fluency, the distinction of apraxia of speech from progressive nonfluent aphasia, and the designation of a progressive fluent aphasia category.

The stripe of primary lateral sclerosis: focal primary motor cortex hypometabolism seen on fluorodeoxyglucose F18 positron emission tomography

BACKGROUND

Primary lateral sclerosis (PLS) is a progressive upper motor neuron neurodegenerative condition. The diagnosis is made using clinical history, objective neurological assessment, and exclusion of other neurodegenerative disorders.

OBJECTIVE

To evaluate the role of fluorodeoxyglucose F18 positron emission tomography and 3-dimensional stereotactic surface projection in the diagnosis of PLS.

DESIGN

Case series.

SETTING

Outpatient neurology clinic. Patients Three cases of probable PLS. Intervention Fluorodeoxyglucose F18 positron emission tomography in 3 patients with PLS.

RESULTS

Three patients (2 male and 1 female; mean age, 65 years) were identified with a clinical diagnosis of PLS. Fluorodeoxyglucose F18 positron emission tomography demonstrated varying degrees of primary motor cortex hypometabolism.

CONCLUSION

Fluorodeoxyglucose F18 positron emission tomography and 3-dimensional stereotactic surface projection provide a useful diagnostic method to support a clinical diagnosis of PLS.

The Geneva prognostic score and mortality in patients diagnosed with pulmonary embolism by CT pulmonary angiogram

This study prospectively evaluates whether a previously established adverse outcome score (the Geneva prognostic score) predicts 3 and 12-month overall mortality among the patients diagnosed with pulmonary embolism (PE) by a CT pulmonary angiogram (CTPA). Five hundred twenty-three consecutive patients who had CTPA for suspected PE were recruited prospectively from March 2003 to October 2004. The Geneva prognostic score was calculated for all patients. Twelve-month follow up was completed in all patients in December 2005. There were 105 patients diagnosed with PE. The mean score was 2.71 (standard deviation (SD) 1.25) for those patients who had died (n = 7) and 1.14 (SD 1.19) for those patients who were alive (n = 98) at 3-month follow up (P < 0.001). The mean scores were 2.69 (SD 0.95) for those who had died (n = 13) and 1.04 (SD 1.15) for those patients who were alive (n = 92) at 12-month follow up (P < 0.001). At 3-month follow up, among the 88 patients with a score of 2 or less, three patients (3.4%) died and among 17 patients with a score of greater than 2, four patients (23.5%) died (P = 0.01). At 12-month follow up, five patients (5.7%) with a score of 2 or less died and eight patients (47.1%) with a score of three or more died (P < 0.0001). The Geneva prognostic score stratifies patients with low and high risk for overall mortality at 3 and 12 months among patients diagnosed with PE by CTPA.

The value of [(18)F]fluorodeoxyglucose positron emission tomography/computed tomography in extranodal natural killer/T-cell lymphoma

PURPOSE

To our knowledge, there are no published data pertinent to the use of [(18F)]fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) in patients with natural killer (NK)/T-cell lymphoma. The purpose of this study was to assess the value of FDG PET/CT in this aggressive type of non-Hodgkin lymphoma.

PATIENTS AND METHODS

All patients with NK/T-cell lymphoma referred for FDG PET/CT at our institution from July 2001 to July 2006 were retrospectively studied. PET/CT examinations were blindly reviewed by 2 experienced readers. The results were compared with the status of the disease, which was determined after evaluation of biopsy, laboratory, clinical and conventional imaging examination, and follow-up results. PET/CT results were thereby classified as true-positive, true-negative, false-positive, or false-negative. The degree of FDG uptake in the positive lesions was semiquantified using maximum standard uptake value (SUV(max)).

RESULTS

Twenty-one PET/CT examinations were performed in 10 patients with NK/T-cell lymphoma. For nasal disease, PET/CT was true-positive in 5 cases, true-negative in 15 cases, and positive but unconfirmed in 1 case. For extranasal disease, PET/CT was true-positive in 3 cases, true-negative in 16 cases, and false-negative in 2 cases. The mean SUV(max) in PET-positive lesions in nasal cavities or paranasal sinuses was 16 gm/mL (range, 5-25 gm/mL; median, 19.3 gm/mL). In extranasal disease, the mean SUV(max) was 10.9 gm/mL (range, 4.6-34.1 gm/mL; median, 5.6 gm/mL).

CONCLUSION

Viable NK/T-cell lymphoma is intensely FDG hypermetabolic. PET/CT appears to be sensitive for the detection of disease in the nasopharynx and, to a lesser extent, in extranasal sites.

Focal F-18 fluoro-deoxy-glucose accumulation in the lung parenchyma in the absence of CT abnormality in PET/CT

OBJECTIVE

To demonstrate 3 cases of artifactual focal F-18 fluoro-deoxy-glucose accumulation in the lung parenchyma in the absence of any computed tomographic (CT) abnormality.

MATERIALS AND METHODS

Three patients were examined: a 30-year-old man who had a positron emission tomography (PET)/computed tomography for restaging a biopsy-proven recurrence of head and neck cancer, a 68-year-old woman who was referred for initial staging of esophageal carcinoma, and a 57-year-old man who had a PET/computed tomography for initial staging of melanoma. In each case, there was intense focal activity in the lung parenchyma with no corresponding CT abnormality. Each patient was further evaluated with a repeat PET scan in days 1 and 3 in the first 2 cases and with a delayed repeat acquisition in the third case. Patients were followed for 24, 10, and 1 month, respectively.

RESULTS

In the first 2 cases, the abnormal focal activity in the lungs had resolved in the repeat study. In the third case, the focus of increased activity in the lung had moved more peripherally in the delayed acquisition. Clinical follow-up was negative for disease in the corresponding pulmonary parenchymal sites.

CONCLUSIONS

The finding of significant focal accumulation of fluoro-deoxy-glucose in the lung parenchyma in the absence of corresponding CT abnormality was artifactual. This was likely due to injection technique and the creation of particulate embolus. Positron emission tomography/Computed tomographic readers should be aware of this type of artifact to avoid misinterpretation.

18F-FDG PET/CT in primary central nervous system lymphoma in HIV-negative patients

OBJECTIVE

To determine the value of F-FDG PET/CT in the different manifestations of primary central nervous system lymphoma (PCNSL) in HIV-negative patients.

METHODS

All PCNSL and HIV-negative patients referred for PET/CT in our institution from July 2001 to June 2006 were retrospectively studied. PET/CT examinations were reviewed by two experienced readers and evaluated for each possible anatomical site of nervous system involvement: cerebral, spinal/nerve and ocular. PET/CT results were characterized as true positive or negative and false positive or negative according to the status of the disease, which was determined after the evaluation of biopsies, laboratory, clinical and imaging examinations, and follow-up.

RESULTS

Forty-two PET/CT examinations were carried out in 25 PCNSL patients. For intracerebral disease, PET/CT was true positive in 13 cases, true negative in 27 and false negative in two. For disease involving spinal cord and/or nerves, PET/CT was true positive in four cases, true negative in 37 and false negative in one. For ocular disease, PET was true positive in only one case and false negative in four. The sensitivity of PET/CT in detecting active disease in the brain was 87% (13/15), in the spine/nerves 80% (4/5), and in the eyes only 20% (1/5).

CONCLUSION

PET/CT seems to be sensitive for the detection of viable intracerebral as well as for spinal and peripheral nerve disease, but not for the detection of ocular involvement.

[18F]Fluoro-L-DOPA PET/CT in Congenital Hyperinsulinism

Congenital hyperinsulinism can be divided into diffuse or focal form. The treatment and outcome depend on distinguishing between the 2 forms. Pancreatic venous sampling was the only method available to localize the insulin secretion. [F]Fluoro-levodopa, 3,4-dihydroxy-L-phenylalanine positron emission tomography/computed tomography is a noninvasive imaging investigation and increasingly used to determine the type of hyperinsulinism preoperatively. We present a case of diffuse form of congenital hyperinsulinism demonstrated by the [F]levodopa, 3,4-dihydroxy-L-phenylalanine positron emission tomography/computed tomography preoperatively and review the literature.

Clinical Significance of Diffusely Increased 18F-FDG Uptake in the Thyroid Gland

Our purpose was to determine the clinical significance of diffusely increased (18)F-FDG uptake in the thyroid gland as an incidental finding on PET/CT.

METHODS

All patients who were found to have diffuse thyroid uptake on (18)F-FDG PET/CT in our institution between November 2004 and June 2006 were investigated and compared with an age- and sex-matched control group. The (18)F-FDG uptake in the thyroid was semiquantified using maximum standardized uptake value and correlated to the available serum thyroid-stimulating hormone (TSH) and thyroid peroxidase (TPO) antibody levels using regression analysis.

RESULTS

Of the 4,732 patients, 138 (2.9%) had diffuse thyroid uptake. Clinical information was available for 133 of the 138 patients. Sixty-three (47.4%) had a prior diagnosis of hypothyroidism or autoimmune thyroiditis, of whom 56 were receiving thyroxine therapy. In the control group, consisting of 133 patients with no thyroid uptake, there were 13 (9.8%) with a prior diagnosis of hypothyroidism, 11 of whom were receiving thyroxine therapy. In the study group, 38 (28.6%) of 133 patients did not undergo any further investigation for thyroid disease, whereas 32 (24.1%) of 133 patients were examined for thyroid disease after PET. Nineteen were found with autoimmune thyroiditis or hypothyroidism, and replacement therapy was initiated in 12. No significant correlation was found between maximum standardized uptake value and TSH (P = 0.09) or TPO antibody (P = 0.68) levels.

CONCLUSION

The incidental finding of increased (18)F-FDG uptake in the thyroid gland is associated with chronic lymphocytic (Hashimoto's) thyroiditis and does not seem to be affected by thyroid hormone therapy. SUV correlated neither with the degree of hypothyroidism nor with the titer of TPO antibodies.

Contribution of F-18 FDG PET-CT in the Detection of Systemic Spread of Primary Central Nervous System Lymphoma

PURPOSE

Primary central nervous system lymphoma (PCNSL) accounts for approximately 3% of all primary brain tumors and 1% of all non-Hodgkin lymphomas. Detection of systemic spread of PCNSL, although rare (4%), is very important since therapy is usually modified. Contrast-enhanced computed tomography (CT) is commonly used for systemic staging of PCNSL. No previous case report is available in the published literature elaborating the potential contribution of F-18 FDG PET in systemic staging of PCNSL. The purpose of this case report was to document the potential usefulness of F-18 FDG-PET in the detection of occult systemic involvement in PCNSL.

MATERIALS AND METHODS

A 50-year-old, immunocompetent, male patient completed successful treatment of PCNSL. As part of a routine pretransplant evaluation he had an F-18 FDG PET coregistered with CT (PET-CT). The PET-CT results were then compared with those of contrast-enhanced CT of the chest, abdomen, and pelvis.

RESULTS

The PET-CT examination detected multiple sites of extranodal systemic disease that were not seen in the contrast-enhanced CT of the chest, abdomen, and pelvis (both studies were performed within 24 hours of each other). Percutaneous ultrasound guided biopsy confirmed the presence of systemic spread of PCNSL. The patient's subsequent therapy was modified to include rituximab with cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP). A follow up PET-CT confirmed resolution of systemic spread.

CONCLUSION

F-18 FDG PET coregistered to CT may be a useful examination in the detection and monitoring for systemic spread of the disease in PCNSL patients.

Gardner's syndrome. Case report and discussion of the manifestations of the disorder

Extracolonic manifestations of Gardner's syndrome are common and may precede the detection of colonic polyps. Tc-MDP bone scintigraphy performed on a patient with Gardner's syndrome demonstrated intense uptake of radiotracer within the maxilla and mandible as a result of the dental anomalies associated with this disorder. Nuclear scintigraphy has a role in the imaging of these patients for skeletal anomalies, the detection of thyroid carcinoma, and for skeletal metastases when colon carcinoma is detected.

Extraosseous Tc-99m MDP uptake: a pathophysiologic approach

Scintigraphy with technetium-99m methylene diphosphonate (MDP) delineates a wide spectrum of nonosseous disorders. Neoplastic, hormonal, inflammatory, ischemic, traumatic, excretory, and artifactual entities demonstrate abnormal soft-tissue uptake of Tc-99m MDP. Mechanisms leading to increased extraosseous Tc-99m MDP uptake include extracellular fluid expansion, enhanced regional vascularity and permeability, and elevated tissue calcium concentration. The composition of the calcium deposition and the presence of other metallic ions (eg, iron and magnesium) are important. Soft-tissue Tc-99m MDP uptake is seen in benign (tumoral calcinosis, myositis ossificans) and malignant (sarcomas, adenocarcinomas, metastases) neoplastic entities. Hormonal disturbances in calcium metabolism, especially in hyperparathyroidism, can lead to metastatic calcification, visualized with Tc-99m MDP scintigraphy. Tissue damage from inflammation, infection, or physical trauma results in localized hyperemia, edema, or calcium (and hemosiderin) deposition based on their pathophysiologic characteristics. Urinary tract obstruction, anomalies, or dysfunction are demonstrated by Tc-99m MDP imaging. Common artifacts are related to faulty radiopharmaceutical preparation, Tc-99m MDP administration, and imaging technique. Recognition of these modes of extraskeletal Tc-99m MDP uptake can enhance the diagnostic value of bone scintigraphy.

Transient diaphyseal tibial Tc-99m MDP uptake and bone marrow edema in acute rheumatic fever

The authors describe a patient with acute rheumatic fever and polyarthritis in whom scintigraphy unexpectedly identified Tc-99m MDP uptake in the diaphyses of both tibiae. A dramatic rise in antistreptolysin-O titer and rapid resolution of tibial abnormalities paralleled marked articular improvement. Magnetic resonance imaging demonstrated a pattern consistent with marrow edema in the area of abnormal Tc-99m MDP accumulation. This finding has not been previously described in acute rheumatic fever, and it was suspected that the changes in the tibiae resulted from subclinical diaphyseal hyperemia from the inflammatory process observed in the contiguous joints.

Small cell lung cancer: staging with MR imaging

Small cell lung cancer is an aggressive neoplasm; metastases are detected in two-thirds of patients at diagnosis with use of conventional staging, which includes bilateral bone marrow biopsy, bone scintigraphy, and computed tomography (CT) of the head and abdomen. In 25 patients, small cell lung cancer was staged prospectively with both conventional staging and a magnetic resonance (MR) imaging protocol that included 1.5-T MR imaging of the pelvis, abdomen, spine, and brain. According to conventional staging, 14 patients had extensive disease and 11 patients had limited disease; according to staging with MR, 19 patients had extensive disease and six had limited disease. All metastatic disease sites seen with conventional staging were identified on MR images. MR images showed additional metastatic involvement in bone (four patients) and liver (three patients) not detected at conventional staging. A low-attenuation hepatic lesion on a CT scan was identified as a hemangioma on MR images. These preliminary data suggest that small cell lung cancer may be accurately staged with use of a single MR imaging study.