Baseline Chest Computed Tomography for Early Diagnosis of Invasive Pulmonary Aspergillosis in Hemato-oncological Patients: A Prospective Cohort Study.

Invasive pulmonary aspergillosis (IPA) has dire consequences in hemato-oncological patients. We report our experience with performing routine baseline chest computed tomography for early diagnosis of IPA. We found high rates of proven or probable IPA diagnosed on admission among patients with newly diagnosed acute myeloid leukemia.

The value of FDG-PET/CT in assessing single pulmonary nodules in patients at high risk of lung cancer.

PURPOSE: To evaluate whether PET/low-dose CT (ldCT) using (18)F-fluorodeoxyglucose (FDG) improves characterization of indeterminate single pulmonary nodules (SPNs) in patients at high risk of lung cancer. METHODS: Retrospective analysis of 307 patients who underwent FDG-PET/CT for indeterminate SPNs identified 93 (70 men, age range 46-90 years) at high risk of lung cancer (age >40 years, minimum 10 pack-year smokers). SPNs were evaluated for the presence and intensity of FDG avidity and ldCT patterns. The performance of visual and semiquantitative FDG-PET/ldCT algorithms for characterization of SPNs was compared to that of ldCT. Incongruent FDG-PET and ldCT patterns were analyzed for significance in further patient management. RESULTS: Malignancy was diagnosed in 38% patients. FDG avidity defined 33 SPNs as true-positive (TP) and 2 as false-negative (FN) (malignant), and 41 as true-negative (TN) and 17 as false-positive (FP) (benign). For SUVmax of 2.2 (by ROC analysis) there were 27 TP, 8 FN, 48 TN and 10 FP SPNs. LdCT defined 34 TP, 1 FN, 28 TN and 30 FP lesions. Of the FP lesions on ldCT, 60% were FDG-negative. Visual PET/ldCT analysis had a sensitivity of 94%, a specificity of 70%, an accuracy of 80%, a positive predictive value (PPV) of 66%, and a negative predictive value (NPV) of 95% as compared to 77%, 83%, 81%, 73%, 86% for semiquantitative PET/ldCT and 97%, 48%, 66%, 53%, 96% for ldCT, respectively. Both PET/ldCT algorithms had statistically significantly higher specificity and accuracy than ldCT. Semiquantitative analysis showed significantly higher PPV and lower sensitivity and NPV than found with ldCT. CONCLUSION: A single screening procedure encompassing FDG-PET and ldCT may improve screening for lung cancer in high-risk patients. The significantly improved specificity may potentially reduce FP ldCT results and further unnecessary invasive procedures.

The incremental value of 18F-FDG PET/CT in paediatric malignancies.

PURPOSE: (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) imaging has been used in the assessment of paediatric malignancies. PET/CT increases the diagnostic accuracy in adult cancer patients. The present study assesses the incremental value of FDG PET/CT in paediatric malignancies. METHODS: A total of 118 (18)FDG PET/CT studies of 46 paediatric patients were reviewed retrospectively. PET and PET/CT results were classified as malignant, equivocal or benign, compared on a site- and study-based analysis, and also compared with the clinical outcome. RESULTS: Three hundred and twenty-four sites of increased FDG uptake were detected. Discordant PET and PET/CT interpretations were found in 97 sites (30%) in 27 studies (22%). PET yielded a statistically significant higher proportion of equivocal and a lower proportion of benign lesion and study results (p<0.001) than PET/CT. With PET there were 153 benign (47%), 84 (26%) equivocal and 87 (27%) malignant sites, while PET/CT detected 226 benign (70%), 10 (3%) equivocal and 88 (27%) malignant lesions. PET/CT mainly improved the characterisation of uptake in brown fat (39%), bowel (17%), muscle (8%) and thymus (7%). The study-based analysis showed that 17 equivocal and seven positive PET studies (20%) were interpreted as benign on PET/CT, while three equivocal studies were interpreted as malignant. The study-based sensitivity and specificity of PET/CT were 92% and 78% respectively. CONCLUSION: PET/CT significantly improved the characterisation of abnormal (18)FDG foci in children with cancer, mainly by excluding the presence of active malignancy in sites of increased tracer activity.

The role of FDG-PET/CT in suspected recurrence of breast cancer.

BACKGROUND: Early diagnosis of recurrent breast cancer is crucial to selection of the most appropriate therapy. The current study evaluated the role of FDG-PET/CT in the assessment of suspected recurrent breast cancer in patients who presented with elevated serum tumor markers. METHODS: Forty-seven consecutive FDG-PET/CT studies of 46 women (aged 32-79 years; mean, 59.9 years) with a history of breast cancer presented with elevated serum tumor markers 1-21 years (mean = 6.2 years) after their initial diagnosis and were retrospectively evaluated. PET/CT results were confirmed by pathology (n = 11), further imaging, and follow-up (mean = 17.2 months; n = 36). Changes in further management based on PET/CT were recorded. RESULTS: Thirty (65%) patients had tumor recurrence, and 16 (35%) patients showed no further evidence of disease. Thirty-one patients had 32 abnormal PET/CT studies, and 15 patients had normal studies with an overall sensitivity, specificity, and accuracy of 90%, 71%, and 83%, respectively. In 37 patients, PET/CT was compared with contrast-enhanced CT and had a higher sensitivity (85% vs 70%), specificity (76% vs 47%), and accuracy (81% vs 59%). PET/CT had an impact on the management of 24 (5l%) patients. Of these, chemotherapy or radiotherapy was started in 16 patients, treatment was modified in 2 patients, and 6 patients were referred to biopsy, followed by referral to surgery for 2 patients. CONCLUSIONS: In patients with breast cancer and rising tumor markers, FDG-PET/CT had high performance indices and was superior to CT for diagnosis of tumor recurrence, which led to changes in the subsequent clinical management of 51% of these patients.

SPECT/CT using 67Ga and 111In-labeled leukocyte scintigraphy for diagnosis of infection.

UNLABELLED: The present study evaluated the role of SPECT/CT as an adjunct to (67)Ga (GS) or (111)In-labeled white blood cell (WBC) scintigraphy for diagnosis or localization of infection. METHODS: Eighty-two patients (56 male and 26 female; mean age, 62 y) assessed for known or suspected infectious processes underwent 88 SPECT/CT studies. Forty-seven patients underwent GS SPECT/CT (13 with fever of unknown origin, 21 with suspected osteomyelitis, and 13 with suspected soft-tissue infection), and 35 patients underwent WBC SPECT/CT (24 with suspected vascular graft infection, and 11 with suspected osteomyelitis). Ninety-eight suggestive sites were identified (52 on GS and 46 on WBC). Additional information provided by SPECT/CT for diagnosis or localization of infection, as compared with planar and SPECT scintigraphy, was recorded. The SPECT/CT contribution was analyzed on a patient and site basis and was compared for the 2 tracers and clinical indications. RESULTS: SPECT/CT provided additional information for infection diagnosis and localization in 39 (48%) of 82 patients and in 47 (48%) of 98 sites. SPECT/CT defined the extent of infection in 35 patients (43%) in 43 sites (44%) and excluded infection in 4 suggestive sites defined as physiologic bowel uptake on GS. SPECT/CT was incorrect in 2 suggestive sites (1 GS and 1 WBC). The contribution of SPECT/CT was significantly higher for WBC than for GS (P < 0.05)--in 63% versus 36% of patients, respectively, and in 61% versus 36% of sites, respectively. CONCLUSION: SPECT/CT made an incremental contribution to GS and WBC in 48% of patients with suspected infections, by improving diagnosis, localization, and definition of extent of disease. SPECT/CT has an important role mainly with highly specific, low-background infection-seeking tracers such as WBC.

Rheumatoid lung nodulosis and osteopathy associated with leflunomide therapy.

BACKGROUND: Leflunomide (LEF) is indicated in adults for the treatment of active rheumatoid arthritis (RA). LEF inhibits dehydroorotate dehydrogenase, a key enzyme of the pyrimidine synthesis in activated lymphocytes. Among rare adverse effects, fatal interstitial lung disease has been recently reported during treatment of RA with LEF in Japan. Clinical trials outside Japan do not suggest that LEF causes an excess of pulmonary adverse effects. Development and increase of peripheral rheumatoid nodules in typical sites of RA patients following LEF therapy has been recently reported. OBJECTIVES: Two cases with new and accelerated development of rheumatoid lung nodulosis during LEF therapy were described in this study. METHODS: LEF treatment was administered to two male patients (77 and 66 years old) with long-standing active seropositive nodular RA with failure of multiple second line drugs and without lung involvement. Clinical and laboratory assessment using the American College of Rheumatology response criteria, chest computed tomography (CT), quantification of serum rheumatoid factor (RF), and monocyte count of peripheral blood along with routine laboratory follow up were performed on both patients before and during therapy. In case 1, a bone scan was performed due to sustained limbs pain. Open lung biopsy was performed in case 1 and core lung biopsy in case 2. RESULTS: Both patients achieved full clinical remission during 2 months of LEF therapy. In case 1, the first complaints were limbs pain after 10 months of treatment associated with intensive bone uptake on a bone scan consistent with hypertrophic pulmonary osteopathy. Productive cough developed after 3 months of the therapy in case 2. Initially, these complaints were not attributed to therapy. New lung disease was present on CT with cherry-like progressive cavitary nodules, predominantly involving the basal segments of the right lung. The first lung lesions were found by CT 13 months (case 1) and 7 months (case 2) after the beginning of therapy and were erroneously related to bronchiectasia in case 2. In both cases, the lung biopsy showed necrosis surrounded by epithelioid mononuclear inflammation with giant cells, consistent with rheumatoid lung node. The time that elapsed between the beginning of the first symptoms to LEF discontinuation was very long: 13 months in case 1 and 24 months in case 2. Discontinuation of LEF therapy was followed by an arrest in growth of lung nodules, resolution of limb pain, and gradual improvement of bone scan. A significant decrease of monocyte count and RF level in peripheral blood was observed during LEF therapy in both cases. CONCLUSION: For the first time, we described rheumatoid lung nodulosis as complication of successful LEF therapy for RA. Hypertrophic pulmonary osteopathy with severe limbs pain and dry cough were the first manifestations of the lung nodulosis. Monocytopenia during LEF therapy is proposed to be involved in pathogenesis of this rare complication of LEF therapy.

Technetium-99m-MIBI SPECT/CT in primary hyperparathyroidism.

The novel trend toward focused parathyroidectomy requires precise preoperative localization of the parathyroid adenoma in patients with primary hyperparathyroidism (PHPT). The present study evaluated the impact of hybrid single photon emission computed tomography/computed tomography (SPECT/CT), using 99mTc-sestamibi (MIBI), on the surgical management of these patients. In a retrospective study of 36 patients with PHPT, SPECT/CT was undertaken when planar 99mTc-MIBI scintigraphy was negative or when an ill-defined focus in the neck or an ectopic site on planar views was visualized. Imaging data were compared with intraoperative findings, and the incremental value of SPECT/CT to lesion localization and surgical procedure was assessed. Three patients with both negative planar and SPECT/CT studies subsequently underwent bilateral neck exploration, with multiglandular hyperplasia diagnosed in two patients and a parathyroid adenoma in one. Of 33 patients with a positive MIBI study, parathyroid adenoma was confined to the neck in 23 patients and to the lower neck-mediastinum in 10. SPECT/CT facilitated the surgical exploration of all 10 ectopic parathyroid adenomas and 4 of 23 cervical parathyroid adenomas, the latter four either at reexploration or in patients with nonvisualization of the thyroid after thyroidectomy. SPECT/CT contributed to the localization of parathyroid adenomas in patients with PHPT and to planning the surgical exploration in 14 of 36 (39%) patients, predominantly those with ectopic parathyroid adenomas or who had distorted neck anatomy.

Is 18F-FDG PET/CT useful for imaging and management of patients with suspected occult recurrence of cancer?

UNLABELLED: Rising serum tumor markers may be associated with negative imaging in the presence of cancer. CT and (18)F-FDG PET may yield incongruent results in the assessment of tumor recurrence. The present study evaluates the incremental role of (18)F-FDG PET/CT for the diagnosis and management of cancer patients with increasing levels of tumor markers as the sole indicator of potential recurrence after initial successful treatment. METHODS: Thirty-six cancer patients with increasing levels of tumor markers during follow-up and negative CT underwent (18)F-FDG PET/CT, which showed 111 sites of increased tracer uptake. PET/CT was compared with PET results on a site-based analysis for characterization of (18)F-FDG foci and on a patient-based analysis for diagnosis of recurrence. The clinical impact of PET/CT on further patient management was evaluated. RESULTS: Thirty patients (83%) had recurrence in 85 malignant sites (77%). For the site-based analysis, PET had a sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 96%, 50%, 85%, 85%, and 82%, respectively, as compared with the performance indices of PET/CT of 100%, 89%, 97%, 97%, and 100%, respectively. There was a statistically significant difference between the specificity (P < 0.05) and accuracy (P < 0.001) of PET and PET/CT for precise characterization of suspected lesions. For the patient-based analysis, PET had a sensitivity, specificity, and accuracy of 93%, 50%, and 86%, respectively, as compared with PET/CT with values of 93%, 67%, and 89%, respectively (P = not significant). PET/CT was the single modality that directed further management and treatment planning in 12 patients (33%). CONCLUSION: The results of this study indicate that PET/CT may improve the accuracy of occult cancer detection and further lead to management changes in patients with increasing levels of tumor markers as the sole suspicion of recurrent malignancy.

PET/CT using 18F-FDG in suspected lung cancer recurrence: diagnostic value and impact on patient management.

UNLABELLED: The goal of this study was to assess the value of hybrid imaging using a combined PET/CT device with 18F-FDG in the diagnosis and clinical management of suspected recurrent lung cancer. METHODS: Forty-two patients with non-small cell lung cancer (NSCLC) with suspected recurrence due to new clinical, biochemical, and radiologic findings were prospectively evaluated. PET/CT results were compared with PET interpreted with side-by-side CT data. A final diagnosis of recurrence was confirmed by histologic tissue sampling during surgery or biopsy or by further clinical and radiologic work-up. The impact of PET/CT on patient management was assessed. RESULTS: Twenty-four of 27 positive PET/CT studies (89%) were proven to have recurrent disease. Fourteen of 15 negative PET/CT studies (93%) had no evidence of disease. The sensitivity, specificity, and positive and negative predictive values of PET/CT for diagnosis of recurrence were 96%, 82%, 89%, and 93% compared with 96%, 53%, 75%, and 90%, respectively, for PET. PET/CT changed the PET lesion classification in 22 patients (52%), by determining the precise localization of sites of increased 18F-FDG uptake. PET/CT changed the management of 12 patients (29%) by eliminating previously planned diagnostic procedures (5 patients), by initiating a previously unplanned treatment option (4 patients), or by inducing a change in the planned therapeutic approach (3 patients). CONCLUSION: In patients with a suspected recurrence of NSCLC, PET/CT provides a better anatomic localization of suspicious lesions compared with PET interpreted with side-by-side CT data. This improved diagnostic performance of PET/CT has a further impact on the clinical management and treatment planning of the patients.

Combined functional and structural evaluation of cancer patients with a hybrid camera-based PET/CT system using (18)F-FDG.

UNLABELLED: Correct diagnosis and definition of the functional and anatomic status of lesions in cancer patients are of clinical importance. The value of hybrid imaging using a gamma camera-based PET/CT and (18)F-FDG in determining the relationship between mass and cancer was assessed. METHODS: Hybrid imaging was performed using a device combining low-dose CT and gamma camera-based PET. Ninety-one patients with histologically proven malignancy and 190 suspected sites of disease were evaluated. Camera-based PET was performed after the injection of 296-370 MBq (18)F-FDG. The presence of organomegaly or an abnormal mass on CT and of abnormal uptake of (18)F-FDG was assessed for each suspected lesion. The presence of malignancy at each site was determined by biopsy, imaging follow-up, or clinical outcome. RESULTS: Five imaging patterns were found. Pattern 1 showed congruent abnormal (18)F-FDG uptake and a mass on CT in 110 of the lesions. One hundred two sites (93%) had active cancer. Pattern 2 showed a mass on CT, larger than the area of abnormal (18)F-FDG uptake, and was found in 5 lesions. Active malignancy was proven in 3 sites (60%). Pattern 3 showed an abnormal mass on CT with no (18)F-FDG uptake and was found in 52 lesions. Thirteen of these lesions (25%) had active tumor. Pattern 4 showing abnormal (18)F-FDG uptake with no mass on CT was found in 23 lesions. Sixteen of these sites (70%) were malignant. Pattern 5 showed normal CT findings and no abnormal (18)F-FDG uptake in 11 patients. Two of these patients (18%) had active disease. Hybrid imaging was of value in establishing the correct relationship between CT and (18)F-FDG findings in 98 of the 190 lesions (52%). CONCLUSION: A range of patterns presenting with or without abnormal (18)F-FDG uptake on camera-based PET and a mass on CT may occur in suspected cancer sites. Both structural changes on CT and increased cell metabolism expressed by abnormal (18)F-FDG uptake should be considered in oncologic imaging. Hybrid imaging, a combined physiologic and anatomic modality, appears to provide new diagnostic opportunities in characterizing function and morphology in malignancies.