Addressing Global Inequities in Positron Emission Tomography-Computed Tomography (PET-CT) for Cancer Management: A Statistical Model to Guide Strategic Planning

The yield of total body CT in the workup of fever of unknown origin in hospitalized medical patients

INTRODUCTION

Total body computerized tomography (TBCT) is frequently used as a diagnostic tool for fever of unknown origin (FUO) workup instead of a recommended fluorodeoxyglucose positron emission tomography FDG-PET/CT. We have assessed the TBCT diagnostic yield on a large, unselected cohort of patients with FUO.

METHODS

We performed a single-center retrospective cohort study, examining all patients hospitalized in internal medicine between 2012 and 2019 with a documented fever and three negative blood cultures who subsequently had a total-body CT performed. After manually reviewing, we included 408 who met the criteria of FUO. We defined a positive study as a scan that led to the documented final diagnosis.

RESULTS

A total of 164 patients (40.2 %) had a positive TBCT result. The majority of positive CT findings were of infectious etiologies (58.5 %), followed by neoplasms (22.8 %) and inflammatory disorders (14.0 %), with the chest (43.9 %) and abdomen (29.8 %) most affected. Using a logistic regression model, a positive scan results were associated with an elevated CRP (p<0.001). Decision tree analysis showed that 55 % of scans of patients with an elevated CRP (>6 mg/dL), low hemoglobin and high leucocyte count (>18000/ml) were positive. Patients without an elevated CRP had a positive scan in only 26 % of tests, and those with also an elevated albumin (>4 gr/dL) and low CRP had positive scan in only 11 % of cases.

CONCLUSIONS

TBCT has a clinically significant yield under specific clinical scenarios in medical patients with FUO- reaching 55 % in patients with an elevated CRP and leukocyte count and low hemoglobin. It is reasonable to proceed to TTBCT when FDG-PET/CT is unavailable and in well-defined clinical situations.

Evaluation of the 2023 Duke-International Society of Cardiovascular Infectious Diseases Criteria in a Multicenter Cohort of Patients With Suspected Infective Endocarditis

BACKGROUND

Since publication of Duke criteria for infective endocarditis (IE) diagnosis, several modifications have been proposed. We aimed to evaluate the diagnostic performance of the Duke-ISCVID (International Society of Cardiovascular Infectious Diseases) 2023 criteria compared to prior versions from 2000 (Duke-Li 2000) and 2015 (Duke-ESC [European Society for Cardiology] 2015).

METHODS

This study was conducted at 2 university hospitals between 2014 and 2022 among patients with suspected IE. A case was classified as IE (final IE diagnosis) by the Endocarditis Team. Sensitivity for each version of the Duke criteria was calculated among patients with confirmed IE based on pathological, surgical, and microbiological data. Specificity for each version of the Duke criteria was calculated among patients with suspected IE for whom IE diagnosis was ruled out.

RESULTS

In total, 2132 episodes with suspected IE were included, of which 1101 (52%) had final IE diagnosis. Definite IE by pathologic criteria was found in 285 (13%), 285 (13%), and 345 (16%) patients using the Duke-Li 2000, Duke-ESC 2015, or the Duke-ISCVID 2023 criteria, respectively. IE was excluded by histopathology in 25 (1%) patients. The Duke-ISCVID 2023 clinical criteria showed a higher sensitivity (84%) compared to previous versions (70%). However, specificity of the new clinical criteria was lower (60%) compared to previous versions (74%).

CONCLUSIONS

The Duke-ISCVID 2023 criteria led to an increase in sensitivity compared to previous versions. Further studies are needed to evaluate items that could increase sensitivity by reducing the number of IE patients misclassified as possible, but without having detrimental effect on specificity of Duke criteria.

New Horizons in Hyperpolarized 13C MRI

Hyperpolarization techniques significantly enhance the sensitivity of magnetic resonance (MR) and thus present fascinating new directions for research and applications with in vivo MR imaging and spectroscopy (MRI/S). Hyperpolarized 13C MRI/S, in particular, enables real-time non-invasive assessment of metabolic processes and holds great promise for a diverse range of clinical applications spanning fields like oncology, neurology, and cardiology, with a potential for improving early diagnosis of disease, patient stratification, and therapy response assessment. Despite its potential, technical challenges remain for achieving clinical translation. This paper provides an overview of the discussions that took place at the international workshop "New Horizons in Hyperpolarized 13C MRI," in March 2023 at the Bavarian Academy of Sciences and Humanities, Munich, Germany. The workshop covered new developments, as well as future directions, in topics including polarization techniques (particularly focusing on parahydrogen-based methods), novel probes, considerations related to data acquisition and analysis, and emerging clinical applications in oncology and other fields.

Neuroendocrine neoplasms: Consensus on a patient care pathway

People with neuroendocrine neoplasms (NENs) face a multitude of challenges, including delayed diagnosis, low awareness of the cancer among healthcare professionals and limited access to multidisciplinary care and expert centres. We have developed the first patient care pathway for people living with NENs in England to guide disease management and help overcome these barriers. The pathway was developed in two phases. First, a pragmatic review of the literature was conducted, which was used to develop a draft patient care pathway. Second, the draft pathway was then updated following semi-structured interviews with carefully selected expert stakeholders. After each phase, the pathway was discussed among a multidisciplinary, expert advisory group (which comprised the authors and the Deputy Chief Operating Officer, West Suffolk NHS Foundation Trust), who reached a consensus on the ideal care pathway. This article presents the outputs of this research. The pathway identified key barriers to care and highlighted how these may be addressed, with many of the findings relevant to the rest of the UK and international audiences. NENs are increasing in incidence and prevalence in England, compounding pre-existing inequities in diagnosis and disease management. Effective integration of this pathway within NHS England will help achieve optimal, equitable care provision for all people with NENs, and should be feasible within the existing expert multidisciplinary teams across the country.

Predicting FDG-PET Images From Multi-Contrast MRI Using Deep Learning in Patients With Brain Neoplasms

BACKGROUND

18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is valuable for determining presence of viable tumor, but is limited by geographical restrictions, radiation exposure, and high cost.

PURPOSE

To generate diagnostic-quality PET equivalent imaging for patients with brain neoplasms by deep learning with multi-contrast MRI.

STUDY TYPE

Retrospective.

SUBJECTS

Patients (59 studies from 51 subjects; age 56 ± 13 years; 29 males) who underwent 18 F-FDG PET and MRI for determining recurrent brain tumor.

FIELD STRENGTH/SEQUENCE

3T; 3D GRE T1, 3D GRE T1c, 3D FSE T2-FLAIR, and 3D FSE ASL, 18 F-FDG PET imaging.

ASSESSMENT

Convolutional neural networks were trained using four MRIs as inputs and acquired FDG PET images as output. The agreement between the acquired and synthesized PET was evaluated by quality metrics and Bland-Altman plots for standardized uptake value ratio. Three physicians scored image quality on a 5-point scale, with score ≥3 as high-quality. They assessed the lesions on a 5-point scale, which was binarized to analyze diagnostic consistency of the synthesized PET compared to the acquired PET.

STATISTICAL TESTS

The agreement in ratings between the acquired and synthesized PET were tested with Gwet's AC and exact Bowker test of symmetry. Agreement of the readers was assessed by Gwet's AC. P = 0.05 was used as the cutoff for statistical significance.

RESULTS

The synthesized PET visually resembled the acquired PET and showed significant improvement in quality metrics (+21.7% on PSNR, +22.2% on SSIM, -31.8% on RSME) compared with ASL. A total of 49.7% of the synthesized PET were considered as high-quality compared to 73.4% of the acquired PET which was statistically significant, but with distinct variability between readers. For the positive/negative lesion assessment, the synthesized PET had an accuracy of 87% but had a tendency to overcall.

CONCLUSION

The proposed deep learning model has the potential of synthesizing diagnostic quality FDG PET images without the use of radiotracers.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

Advanced Breast Cancer Guidelines in Latin America: Assessment, Adaptation, and Implementation of Fifth Advanced Breast Cancer Consensus Guidelines

PURPOSE

As the fifth international consensus on advanced breast cancer (ABC5) established guidelines for the management of this disease, the aim of this article was to present the applicability of the consensus recommendations and to generate knowledge to improve access.

METHODS

Sixty-one recommendation statements were selected and discussed by 15 breast cancer experts from Latin America (LA). After the discussion, the level of consensus was determined through a vote. In addition to this, the level of access to each of the recommendations presented, according to the country and health system, was exposed.

RESULTS

Latin American experts had a high level of agreement with the ABC5 consensus recommendations (range, 83%-100%). Twelve of 61 statements are not available for all patients in LA. Among the limitations to access, the following ones are described: limited access to certain technologies (stereotactic body radiotherapy, positron emission tomography-computed tomography), the high costs of drugs that limits access to treatment with CDK4/6 inhibitors, pertuzumab, or poly(ADP-ribose) polymerase inhibitors, and the lack of molecular tests for access to therapeutic targets, as well as the difficult geography and cultural diversity of our continent.

CONCLUSION

Despite the great relevance of the recommendations of the ABC5 consensus guidelines, we highlight that we still need to improve access for all patients, regardless of the country or health system they are in, for which we call to action to policy makers and patient groups to improve clinical outcomes of patients with advanced breast cancer in our region.

PET-CT-guided versus CT-guided biopsy in suspected malignant pleural thickening: a randomised trial

BACKGROUND

Pleural biopsy is the gold standard for diagnosis of pleural malignancy but a significant proportion will have an inconclusive biopsy despite ongoing clinical suspicion of malignancy. We investigated whether positron emission tomography-computed tomography (PET-CT) targeted pleural biopsy is superior to standard CT-guided pleural biopsy following an initial non-diagnostic biopsy.

METHODS

The TARGET trial was a multicentre, parallel group randomised trial. Patients with a previous inconclusive pleural biopsy but an ongoing suspicion of pleural malignancy were randomised (1:1) to receive either CT-guided biopsy (standard care) or PET-CT followed by a targeted CT biopsy (intervention). The primary outcome was pleural malignancy correctly identified from the trial biopsy.

RESULTS

Between September 2015 and September 2018, 59 participants were randomised from eight UK hospital sites: 29 to CT-only followed by targeted biopsy and 30 to PET-CT followed by targeted biopsy. The proportion of pleural malignancy correctly identified was similar between the groups (risk ratio 1.03 (95% CI 0.83-1.29); p=0.77). The sensitivity of the trial biopsy to identify pleural malignancy was 79% (95% CI 54-94%) in the CT-only group versus 81% (95% CI 54-96%) in the PET-CT group.

CONCLUSIONS

The results do not support the practice of PET-CT to guide pleural biopsies in patients with a previous non-diagnostic biopsy. The diagnostic sensitivity in the CT-only group was higher than anticipated and supports the practice of repeating a CT-guided biopsy following an inconclusive result if clinical suspicion of malignancy persists.

The quest for multifunctional and dedicated PET instrumentation with irregular geometries

We focus on reviewing state-of-the-art developments of dedicated PET scanners with irregular geometries and the potential of different aspects of multifunctional PET imaging. First, we discuss advances in non-conventional PET detector geometries. Then, we present innovative designs of organ-specific dedicated PET scanners for breast, brain, prostate, and cardiac imaging. We will also review challenges and possible artifacts by image reconstruction algorithms for PET scanners with irregular geometries, such as non-cylindrical and partial angular coverage geometries and how they can be addressed. Then, we attempt to address some open issues about cost/benefits analysis of dedicated PET scanners, how far are the theoretical conceptual designs from the market/clinic, and strategies to reduce fabrication cost without compromising performance.

Esophageal cancer - the utility of PET/CT in staging prior to chemoradiation

Background

Thorough staging plays a significant role in determining therapy modality in esophageal cancer patients. The aim of this study was to assess whether positron emission tomography/computed tomography (PET/CT) may be safely omitted in selected groups of patients.

Materials and methods

This retrospective analysis included 37 esophageal cancer patients recruited to chemoradiation by the Multidisciplinary Tumor Board (MTB) at the Greater Poland Cancer Center in 2021. Prior to radiotherapy planning every patient was referred to PET/CT to have the extent of their disease assessed.

Results

Among 37 patients PET/CT changed the staging status to metastatic (M1) in six cases (3 planoepithelial and 3 adenocarcinomas). In all those cases but one (1 patient with supraclavicular node metastasis finally received chemoradiation) confirmation of distant metastases excluded patients from radical treatment. Interestingly, in the PET/CT distant positive group 3 patients were initially staged as locally advanced (without nodal involvement). The other 3 were initially identified as at least N2 in tomography.

Conclusion

Results of this report allowed the conclusion that PET/CT plays a key role in esophageal cancer patients considered for radical chemoradiation; therefore, it remains a necessary tool to exclude metastatic disease in both main pathology types. Since the delayed time for PET/CT scan in esophageal cancer patients planned to chemoradiation may negatively influence treatment results, the data should be alarming for national health provider.

Granulocyte Colony-stimulating Factor-associated Aortitis on Gallium Scintigraphy

Aortitis is a rare adverse event associated with granulocyte colony-stimulating factor (G-CSF). Contrast-enhanced computed tomography (CECT) is widely used to diagnose G-CSF-associated aortitis. However, the usefulness of gallium scintigraphy for the diagnosis of G-CSF-associated aortitis is unknown. We herein report a set of pre- and post-treatment gallium scintigrams of a patient with G-CSF-associated aortitis. During the diagnosis, gallium scintigraphy revealed hot spots on the arterial walls that appeared inflamed on CECT. Both the CECT and gallium scintigraphy findings disappeared. Gallium scintigraphy can be a supportive diagnostic tool for G-CSF-associated aortitis, especially in patients with an impaired renal function or allergy to iodine contrast.

Diffuse Large B-Cell Lymphoma Treated With R-CHOP in a Resource-Limited Setting in South Africa: A Real-World Study

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin's lymphoma worldwide and particularly in Africa, where the incidence of HIV is the highest in the world. R-CHOP is the standard of care regimen for DLBCL, but access to rituximab is limited in developing countries.

METHODS

This is a retrospective cohort study that included all HIV-negative patients with DLBCL who received R-CHOP at a single institution from January 2012 to December 2017. Clinical and demographic data were collected to assess factors that influenced survival.

RESULTS

Seventy-three patients were included. Median age was 55 (17-76), 67.1% of patients were younger than 60 years, and 60.3% were female. Most presented with stages III/IV disease (53.5%) but with good performance status (56.% PS 0 and 1). Progression-free survival at 3 and 5 years was 75% and 69%, and overall survival at 3 and 5 years was 77% and 74%, respectively. Median survival had not been reached with a median follow-up of 3.5 years(0.13-7.9). Overall survival was significantly affected by performance status (P = .04), but not by IPI or age. Survival was significantly associated with response to chemotherapy after 4-5 cycles of R-CHOP (P = 0.005).

CONCLUSIONS

Treatment of DLBCL with R-CHOP is feasible and can achieve good outcomes in resource-limited settings with rituximab-based chemotherapy. Poor performance status was the most important adverse prognostic factor in this cohort of HIV-negative patients.

Gut microbiome composition may be an indicator of preclinical Alzheimer's disease

Alzheimer's disease (AD) pathology is thought to progress from normal cognition through preclinical disease and ultimately to symptomatic AD with cognitive impairment. Recent work suggests that the gut microbiome of symptomatic patients with AD has an altered taxonomic composition compared with that of healthy, cognitively normal control individuals. However, knowledge about changes in the gut microbiome before the onset of symptomatic AD is limited. In this cross-sectional study that accounted for clinical covariates and dietary intake, we compared the taxonomic composition and gut microbial function in a cohort of 164 cognitively normal individuals, 49 of whom showed biomarker evidence of early preclinical AD. Gut microbial taxonomic profiles of individuals with preclinical AD were distinct from those of individuals without evidence of preclinical AD. The change in gut microbiome composition correlated with β-amyloid (Aβ) and tau pathological biomarkers but not with biomarkers of neurodegeneration, suggesting that the gut microbiome may change early in the disease process. We identified specific gut bacterial taxa associated with preclinical AD. Inclusion of these microbiome features improved the accuracy, sensitivity, and specificity of machine learning classifiers for predicting preclinical AD status when tested on a subset of the cohort (65 of the 164 participants). Gut microbiome correlates of preclinical AD neuropathology may improve our understanding of AD etiology and may help to identify gut-derived markers of AD risk.

Long-axial field-of-view PET/CT: perspectives and review of a revolutionary development in nuclear medicine based on clinical experience in over 7000 patients

Recently introduced long-axial field-of-view (LAFOV) PET/CT systems represent one of the most significant advancements in nuclear medicine since the advent of multi-modality PET/CT imaging. The higher sensitivity exhibited by such systems allow for reductions in applied activity and short duration scans. However, we consider this to be just one small part of the story: Instead, the ability to image the body in its entirety in a single FOV affords insights which standard FOV systems cannot provide. For example, we now have the ability to capture a wider dynamic range of a tracer by imaging it over multiple half-lives without detrimental image noise, to leverage lower radiopharmaceutical doses by using dual-tracer techniques and with improved quantification. The potential for quantitative dynamic whole-body imaging using abbreviated protocols potentially makes these techniques viable for routine clinical use, transforming PET-reporting from a subjective analysis of semi-quantitative maps of radiopharmaceutical uptake at a single time-point to an accurate and quantitative, non-invasive tool to determine human function and physiology and to explore organ interactions and to perform whole-body systems analysis. This article will share the insights obtained from 2 years' of clinical operation of the first Biograph Vision Quadra (Siemens Healthineers) LAFOV system. It will also survey the current state-of-the-art in PET technology. Several technologies are poised to furnish systems with even greater sensitivity and resolution than current systems, potentially with orders of magnitude higher sensitivity. Current barriers which remain to be surmounted, such as data pipelines, patient throughput and the hindrances to implementing kinetic analysis for routine patient care will also be discussed.

Frequency and malignancy rate of incidental focal salivary gland lesions identified by 18F-fluorodeoxyglucose-positron emission tomography

PURPOSE

We aimed to evaluate the frequency and malignancy rate of incidental salivary gland lesions (ISGLs) in patients undergoing 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT).

METHODS

Using a predefined algorithm, all descriptions of FDG-PET/CT scans performed in the North Denmark Region at the Department of Nuclear Medicine, Aalborg University Hospital from 1.12 2009 to 31.12 2019 were electronically searched for focal uptake in one or more salivary glands.

RESULTS

In total, 28,362 FDG-PET/CT scans were performed in the study period. ISGLs were found in 197 (0.7%). A total of 193 (98%) had parotid gland ISGL, and four (2%) had submandibular ISGL. No sublingual lesions were found. Ultimately, 117 patients (60%) were referred to the Department of Otorhinolaryngology-Head and Neck Surgery for evaluation. Fine needle aspiration biopsy was performed in 97 patients, and the most frequent cytopathology was Warthin's tumour (n = 62). Two patients had verified malignancy: one with histopathologically proven acinic cell carcinoma and one with cytopathologically proven metastasis from an oral squamous cell carcinoma.

CONCLUSIONS

Incidental salivary gland findings on FDG-PET/CT are rare, and the risk of malignancy is low. Patients with ISGL may be evaluated secondary to the primary disease, but special attention should be given to patients with prior or known head-and-neck malignancies and patients with symptoms from the salivary glands, including swelling.

A radiomics-based decision support tool improves lung cancer diagnosis in combination with the Herder score in large lung nodules

BACKGROUND

Large lung nodules (≥15 mm) have the highest risk of malignancy, and may exhibit important differences in phenotypic or clinical characteristics to their smaller counterparts. Existing risk models do not stratify large nodules well. We aimed to develop and validate an integrated segmentation and classification pipeline, incorporating deep-learning and traditional radiomics, to classify large lung nodules according to cancer risk.

METHODS

502 patients from five U.K. centres were recruited to the large-nodule arm of the retrospective LIBRA study between July 2020 and April 2022. 838 CT scans were used for model development, split into training and test sets (70% and 30% respectively). An nnUNet model was trained to automate lung nodule segmentation. A radiomics signature was developed to classify nodules according to malignancy risk. Performance of the radiomics model, termed the large-nodule radiomics predictive vector (LN-RPV), was compared to three radiologists and the Brock and Herder scores.

FINDINGS

499 patients had technically evaluable scans (mean age 69 ± 11, 257 men, 242 women). In the test set of 252 scans, the nnUNet achieved a DICE score of 0.86, and the LN-RPV achieved an AUC of 0.83 (95% CI 0.77-0.88) for malignancy classification. Performance was higher than the median radiologist (AUC 0.75 [95% CI 0.70-0.81], DeLong p = 0.03). LN-RPV was robust to auto-segmentation (ICC 0.94). For baseline solid nodules in the test set (117 patients), LN-RPV had an AUC of 0.87 (95% CI 0.80-0.93) compared to 0.67 (95% CI 0.55-0.76, DeLong p = 0.002) for the Brock score and 0.83 (95% CI 0.75-0.90, DeLong p = 0.4) for the Herder score. In the international external test set (n = 151), LN-RPV maintained an AUC of 0.75 (95% CI 0.63-0.85). 18 out of 22 (82%) malignant nodules in the Herder 10-70% category in the test set were identified as high risk by the decision-support tool, and may have been referred for earlier intervention.

INTERPRETATION

The model accurately segments and classifies large lung nodules, and may improve upon existing clinical models.

FUNDING

This project represents independent research funded by: 1) Royal Marsden Partners Cancer Alliance, 2) the Royal Marsden Cancer Charity, 3) the National Institute for Health Research (NIHR) Biomedical Research Centre at the Royal Marsden NHS Foundation Trust and The Institute of Cancer Research, London, 4) the National Institute for Health Research (NIHR) Biomedical Research Centre at Imperial College London, 5) Cancer Research UK (C309/A31316).

Toward Improved Outcomes for Patients With Lung Cancer Globally: The Essential Role of Radiology and Nuclear Medicine

PURPOSE

Key to achieving better population-based outcomes for patients with lung cancer is the improvement of medical imaging and nuclear medicine infrastructure globally. This paper aims to outline why and spark relevant health systems strengthening.

METHODS

The paper synthesizes the global lung cancer landscape, imaging referral guidelines (including resource-stratified ones), the reliance of TNM staging upon imaging, relevant multinational health technology assessments, and precisely how treatment selection and in turn patient outcomes hinge upon imaging findings. The final discussion presents data on current global gaps in both diagnostics (including imaging) and therapies and how, informed by such data, improved population-based outcomes are tangible through strategic planning.

RESULTS

Imaging findings are central to appropriate lung cancer patient management and can variably lead to life-prolonging interventions and/or to life-enhancing palliative measures. Early-stage lung cancer can be treated with curative intent but, unfortunately, most patients with lung cancer still present at advanced stages and many patients lack access to both diagnostics and therapies. Furthermore, half of lung cancer cases occur in low- and middle-income countries. The role of medical imaging and nuclear medicine in lung cancer management, as outlined herein, may help inform strategic planning.

CONCLUSION

Lung cancer is the number one cancer killer worldwide. The essential role that medical imaging and nuclear medicine play in early diagnosis and disease staging cannot be overstated, pivotal in selecting the many patients for whom measurably improved outcomes are attainable. Prevention synergized with patient-centered, compassionate, high-quality lung cancer management provision mandate that strategic population-based planning, including universal health coverage strategies, should extend well beyond the scope of disease prevention to include both curative and noncurative treatment options for the millions afflicted with lung cancer.

Analysis of registered radiological equipment in Kenya

INTRODUCTION

diagnostic radiology plays a key role in healthcare. Proper planning of healthcare requires accurate and robust data. There´s, however, paucity of comprehensive figures on radiological equipment in the African setting. The goal of this study was to carry out an in-depth analysis of the registered radiological equipment in Kenya, a lower middle-income African country, and compare the findings to published international data.

METHODS

data on radiological equipment were obtained from the Kenya Nuclear Regulatory Authority and analyzed as units/million of the population by imaging modality, health service sector and administrative units. The findings were then compared to published international data.

RESULTS

there has been an overall increase in the number of radiological equipment in comparison to data published in 2013, with a relatively uniform distribution of resources across all eight regions. General radiography is the most available modality at 24.5 units/million with the majority of the equipment owned privately, while the public sector (9.6 units/million) has less than a half of the WHO recommendation of 20 units/million. Accessibility to computerized tomography (CT) scan, fluoroscopy and mammography in the public sector closely mirrors that of South Africa. On the contrary, positron emission tomography-computerized tomography (PET-CT) is the least-resourced modality and is currently only available in the private sector.

CONCLUSION

the increased number and homogenous distribution of radiological resources can largely be attributed to the Managed Equipment Services project launched by the national government in 2016. More needs to be done with regards to availability of PET/CT scanners and general radiography equipment in the public sector.

A Clinicopathological Study of Cytomegalovirus Lymphadenitis and Tonsillitis and Their Association with Epstein-Barr Virus

Introduction

Histopathological characteristics of cytomegalovirus (CMV) lymphadenitis have been well described. Rare studies have reported the immune status and clinical features. Clinically, experts believed that CMV lymphadenitis develops in immunocompromised and immunocompetent patients. Infectious mononucleosis (IM)-like syndrome is the most well-known clinical presentation.

Methods

We reviewed archived CMV immunohistochemical stains on lymphoid tissues. The clinicopathological features of CMV-positive cases were studied.

Results

For lymph nodes, we detected CMV in 29% (5/17) allogeneic peripheral blood hematopoietic stem cell transplantation (PBSCT) recipients, 29% (4/14) post-autologous PBSCT patients, 13% (6/47) patients treated with intravenous chemotherapy, and 9% (9/96) immunocompetent patients. We detected CMV in 7% (2/24) of tonsils but not in the nasopharynx, tongue base, or spleen specimens. The patients with iatrogenic immunodeficiency ranged from 37 to 76 years old. CMV infections developed a few years after lymphoma treatment (median duration after allogeneic PBSCT, 932 days; after autologous PBSCT, 370 days; and after chemotherapy, 626 days). The most common clinical presentation was neck mass (13/25, 42%), followed by asymptomatic image finding (10/25, 40%). Positron emission tomography/computed tomography (PET/CT) scan showed increased uptake compared to the liver in all patients (11/11, 100%). Of 10 lymphoma patients, 8 (80%) had a Deauville score of 4–5; they accounted for 30% (8/27) of lymphoma patients with false-positive PET/CT scan results. All cases were self-limiting. 96% (23/25) cases had Epstein–Barr virus coinfection, and EBER-positive cells were predominantly in a few germinal centers.

Conclusions

Cytomegalovirus (CMV) lymphadenitis and tonsillitis were subclinical infections, not primary CMV infection with IM-like syndrome. The lymphadenopathy typically developed a few years after lymphoma treatments in the middle-aged and the elderly. The lesions mimicked lymphoma relapse in PET scans. Therefore, recognizing CMV infection in lymphoid tissues is of clinical importance.

Graphic abstract