Early documentation of therapeutic response at 6 weeks following corticosteroid therapy in extensive sarcoidosis: promise of FDG-PET

Hypermetabolic Pulmonary and Mediastinal Lesions With Elevated Cancer Antigen (CA) 15-3 and CA 27-29 in a Patient With a History of Ovarian and Breast Cancer

Breast cancer affects around 13% of women. Breast cancer gene 1 (BRCA1) carriers are prone to lung and lymph node metastasis, while breast cancer gene 2 (BRCA2) carriers tend to have bone metastasis. Findings of pulmonary nodules, mediastinal lymphadenopathy, and elevated markers such as cancer antigen (CA) 15-3 and CA 27-29 suggest metastatic disease. Here, we present the case of a patient with BRCA1-positive breast cancer in remission and a history of ovarian cancer with mediastinal lymphadenopathy and pulmonary nodules, with avid fluorodeoxyglucose uptake on positron emission tomography (PET) scan and elevated CA 15-3 and CA 27-29. A 70-year-old female with a history of bilateral breast and ovarian cancer and a positive BRCA test presented with pulmonary nodules, mediastinal lymphadenopathy, and elevated CA 15-3 and CA 27-29. Imaging showed mediastinal and hilar lymphadenopathy. A PET scan revealed increased metabolic activity in the lymph nodes and pulmonary lesions. Fiberoptic bronchoscopy and endobronchial ultrasound lymph node sampling demonstrated granulomatous inflammation without malignant cells. The patient underwent a therapeutic trial of steroids with clinical improvement of symptoms and decreased hypermetabolic activity in chest lesions, as well as a decrease in tumor markers. The coexistence of sarcoidosis and breast cancer is rare; sarcoidosis can coexist, precede, or appear after breast cancer. In both conditions, tumor markers and PET avidity are seen, which makes diagnosis and management challenging. In case of ambiguity, biopsy is crucial. This case underscores the importance of integrating clinical, pathological, and imaging data to reach an accurate diagnosis and consider a therapeutic trial of steroids. Furthermore, the early PET response to treatment can be pivotal in differentiating between sarcoidosis and malignancy, especially in complex clinical scenarios. Proper differentiation is paramount to avoid therapeutic missteps and ensure appropriate patient management.

A prospective study comparing whole-body skeletal X-ray survey with 18F-FDG-PET/CT, 18F-NaF-PET/CT and whole-body MRI in the detection of bone lesions in multiple myeloma patients

Background

For decades, the most widely used imaging technique for myeloma bone lesions has been a whole-body skeletal X-ray survey (WBXR), but newer promising imaging techniques are evolving.

Purpose

To compare WBXR with the advanced imaging techniques 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT), 18F-sodium fluoride (NaF) PET/CT and whole-body magnetic resonance imaging (WB-MRI) in the detection of myeloma bone lesions.

Material and Methods

Fourteen patients with newly diagnosed multiple myeloma were prospectively enrolled. In addition to WBXR, all patients underwent FDG-PET/CT, NaF-PET/CT, and WB-MRI. Experienced specialists performed blinded readings based on predefined anatomical regions and diagnostic criteria.

Results

In a region-based analysis, a two-sided ANOVA test showed that the extent of detected skeletal disease depends on the scanning technique (P < 0.0001). Tukey’s multiple comparison test revealed that WB-MRI on average detects significantly more affected regions than WBXR (P < 0.005), FDG-PET/CT (P < 0.0001), and NaF-PET/CT (P < 0.05). In a patient-based analysis, a Cochran’s Q test showed that there are no significant differences in the proportion of patients with bone disease detected by the different scanning techniques (P = 0.23). Determination of intrareader variability resulted in Kappa coefficients corresponding to moderate (FDG-PET/CT) and substantial agreement (WB-MRI, WBXR, NaF-PET/CT).

Conclusion

WB-MRI detects on average significantly more body regions indicative of myeloma bone disease compared to WBXR, FDG-PET/CT, and NaF-PET/CT. The lack of significance in the patient-based analysis is most likely due to the small number of study participants.

PET-Based Personalized Management of Infectious and Inflammatory Disorders

It is challenging to diagnose and manage infectious and inflammatory diseases; symptoms are relatively nonspecific, the disease patterns are often systemic. Imaging is pivotal and fluorodeoxyglucose (FDG)-PET/computed tomography (CT) is increasingly used due to its high sensitivity whole-body approach. At present, the literature is still relatively sparse, but evidence for FDG-PET/CT is mounting in several domains, for example, detecting culprit lesions in systemic infections and inflammations, evaluation of disease extent and therapy monitoring, and many other domains have shown considerable potential, for example, atherosclerosis in systemic inflammation. We believe FDG-PET/CT is becoming a first-line modality for infections and inflammation.

18-Fluoro-deoxyglucose-PET/Computed Tomography in Infection and Aseptic Inflammatory Disorders: Value to Patient Management

This communication is aimed specifically at exploring the possible practical advantages and potentials of 18-fluoro-deoxyglucose (FDG)-PET/ computed tomography (CT) that could translate into routine management of patients with infection and aseptic inflammatory disorders. From viewpoint of patient management, the applications can be classified into two broad categories, based upon primary intent of the investigation: [a] Diagnostic (eg, pyrexia of unknown origin and other localized infectious processes) and [b] Undertaking this as part of objective imaging assessment of early treatment response and thereby tailoring/altering therapy (eg, systemic infectious and non-infectious inflammatory diseases). Over the last decade, this promising FDG-PET/CT application has been debated and there is need to make systematic approach for defining its value to patient management.

Utility of FDG-PET-CT scanning in assessing the extent of disease activity and response to treatment in sarcoidosis

Background:

Radionuclide imaging modalities have increasingly been evaluated in the assessment of organ involvement in sarcoidosis. Fluoro-deoxyglucose positron emission tomography–computed tomography (FDG–PET–CT) scanning has received increasing attention in the recent years. The aim of our study was to evaluate the utility of FDG–PET–CT in determining the extent of organ involvement and disease activity in patients of sarcoidosis and to assess its utility in the evaluation of response to therapy. The secondary objective was to compare the agreement between clinical, radiological (HRCT) and metabolic indices (FDG–PET–CT) of disease activity.

Materials and Methods:

This was a prospective observational study conducted between March 2007 and December 2008 at a tertiary care referral center in north India. Twenty-five symptomatic and histopathologically proven cases of sarcoidosis underwent FDG–PET–CT scanning at baseline and a follow-up scan in 21 patients at 6-9 months post-treatment with glucocorticoids.

Results:

FDG–PET–CT scan detected metabolic disease activity in 24 of the 25 patients with clinically active sarcoidosis. It also demonstrated many clinically inapparent sites of disease activity. Complete or partial metabolic response was seen in 17 of the 21 patients in whom a follow-up scan was available. Substantial degree of agreement was found between the metabolic response and the radiological response, whereas moderate agreement was found between clinical and metabolic responses.

Conclusions:

FDG–PET–CT scanning is a useful imaging modality to assess disease activity, extent of disease involvement and response to treatment in clinically active sarcoidosis. There is substantial agreement between the HRCT and metabolic parameters of disease activity. Further, large sample size studies are proposed in order to identify the subset of patients who are likely to benefit the most from this sensitive modality of imaging, especially in developing countries where the cost of the procedure is an important concern.

Positron emission tomography imaging in sarcoidosis

Sarcoidosis is a chronic granulomatous disease of unknown origin. There are several modalities for diagnosis, staging and therapeutic management of patients with sarcoidosis. Among these, whole-body F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography is found to useful in patients with complex and multisystem forms of sarcoidosis. Other modalities include Gallium scanning, assesment of angiotensin converting enzyme levels in blood, chest radiography, mediastinoscopy etcetera.

Clinical utility of FDG-PET and PET/CT in non-malignant thoracic disorders

There have been several endeavors made to investigate the potential role of 2-deoxy-2-[(18)F]fluoro-D-glucose positron emission tomography (FDG-PET) (and tracers) and PET-computed tomography imaging in various benign disorders, particularly those related to thoracic structures. These various conditions can be broadly categorized into three groups: (a) infectious diseases (mycobacterial, fungal, bacterial infection), (b) active granulomatous disease such as sarcoidosis, and (c) other non-infectious/inflammatory conditions or proliferative disorders (e.g., radiation pneumonitis, post-lung transplant lymphoproliferative disorders, occupational pleuropulmonary complications, and post-surgical conditions), all of which can demonstrate varying degrees of FDG uptake on PET scans based upon the degree of inflammatory activity. This article reviews the current state of this very important application of FDG-PET imaging.

Effect of the TNF-α inhibitor adalimumab in patients with recalcitrant sarcoidosis: a prospective observational study using FDG-PET

BACKGROUND

Tumour necrosis factor-alpha (TNF-α) plays a crucial role in sarcoidosis. In severe disease, treatment with TNF-α inhibitors may be effective.

OBJECTIVES

Changes in sarcoid disease activity were assessed by fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in patients with recalcitrant sarcoidosis treated with adalimumab.

METHODS

Prospective 24-week observational study. Patients continued medication with steroids and antimetabolites and received adalimumab 40 mg subcutaneously every other week. Ten patients with biopsy-proven sarcoidosis (two men) were included with a median age of 47 years (range 35-73). An FDG-PET showing uptake indicating sarcoid activity was required at inclusion and repeated at the end of the study. FDG-PET uptake was assessed by calculated standardised uptake value (SUV). Blood samples and lung function tests were performed regularly. Quality of life was assessed by the short-form health survey (SF-36) questionnaire.

RESULTS

Following treatment with adalimumab, FDG-PET uptake decreased in nine patients (P = 0.011) and increased in one patient. Maximum SUV fell from median 14.1 to 7.0 (P < 0.03), and mean SUV fell from median 6.5 to 2.9 (P < 0.02). Six patients had uptake in the lungs, which decreased after treatment (P = 0.035). Six patients had uptake in the lymph nodes, which decreased after treatment in five patients (P = 0.035). Four patients had non-lymphatic extrathoracic uptake, which decreased after treatment (P = 0.05). There was no effect of adalimumab on pulmonary function tests, serum angiotensin I converting enzyme and blood lymphocyte (CD3+, CD4+, CD8+) concentrations. Physical component summary score (SF-36) increased during treatment, mental component summary score was unchanged.

CONCLUSION

In sarcoidosis, treatment with adalimumab can reduce disease activity, as assessed by FDG-PET.

PET/CT in Patients with Sarcoidosis or IgG4 Disease

Sarcoidosis as a distinct disease entity was diagnosed more than 100 years ago. The signs and symptoms of the disease are nonspecific, posing a challenge for early and accurate diagnosis. IgG4 disease or syndrome has various clinical manifestations, such as sclerosing pancreatitis, sclerosing cholangitis, prostatitis, tubulointerstitial nephritis, interstitial pneumonia, and enlargement of salivary glands. This article discusses the role of the different diagnostic imaging modalities in sarcoidosis and IgG4 disease, including radiographs, computed tomography, magnetic resonance imaging, and conventional nuclear medicine, with a special emphasis on positron emission tomography as a superior modality for assessing these inflammatory diseases.

Positron emission tomography for the evaluation and treatment of cardiomyopathy

Congestive heart failure accounts for tremendous morbidity and mortality worldwide. There are numerous causes of cardiomyopathy, the most common of which is coronary artery disease. Positron emission tomography (PET) has an established and expanding role in the evaluation of patients with cardiomyopathy. The specific application of PET to hypertrophic cardiomyopathy, cardiac sarcoidosis, and diabetic cardiomyopathy has been studied extensively and promises to be a useful tool for managing these patients. Furthermore, evaluating the efficacy of standard treatments for congestive heart failure is important as health care costs continue to rise. Recently, there have been significant developments in the field of cardiovascular stem cell research. Familiarity with the mechanisms by which stem cells benefit patients with cardiovascular disease is the key to understanding these advances. Molecular imaging techniques including PET/CT imaging play an important role in monitoring stem cell therapy in both animals and humans. These noninvasive imaging techniques will be highlighted in this paper.