Bone marrow uptake of 18F-fluorodeoxyglucose in Hodgkin lymphoma without bone involvement: comparison between patients with and without B symptoms

Comparison of bone marrow biopsy and fluorodeoxyglucose-positron emission tomography for the assessment of bone marrow infiltration in children with Hodgkin's lymphoma

PURPOSE

To compare bone marrow biopsy (BMB) with [18F]-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (PET/CT) imaging in the demonstration of bone marrow involvement in children with Hodgkin's Lymphoma (HL) and to investigate the effectiveness of PET/CT imaging and thus the necessity for BMB at staging.

METHODS

Pediatric patients with HL, who underwent both bilateral iliac BMB and PET/CT imaging at disease staging were retrospectively analyzed. In determining bone marrow involvement (BMinv), BMB and/or first/follow-up PET/CT imaging were eligible for review.

RESULTS

Fifty-six patients were included. BMinv was detected by PET/CT imaging in 6/56 (10.7%), whereas the proportion was 3/56 (5.3%) in BMB specimens. Bone marrow biopsies and PET/CT images were concordant in 53/56 (94.6%) patients with BMB specimens missing three cases of BMinv detected by PET/CT. When diagnostic accuracy was calculated, sensitivity, specificity, positive predictive value and negative predictive values for PET/CT were 100%, 100%, 100%, 100%, respectively, and the same values for BMB were 50%, 100%, 100%, 94.3%, respectively.

CONCLUSIONS

The results of PET/CT and BMB for staging of pediatric HL patients were compatible, and PET/CT imaging was found to provide high diagnostic performance in determining BMinv. In keeping with earlier research, the current study showed that BMB may not be necessary in every patient at staging, and should be reserved for cases where PET/CT is inconclusive.

Use of PET/CT to aid clinical decision-making in cases of solitary pulmonary nodule: a probabilistic approach

Objective

To determine the frequency with which ¹⁸F-FDG-PET/CT findings change the probability of malignancy classification of solitary pulmonary nodules.

Materials and Methods

This was a retrospective analysis of all ¹⁸F-FDG-PET/CT examinations performed for the investigation of a solitary pulmonary nodule between May 2016 and May 2017. We reviewed medical records and PET/CT images to collect the data necessary to calculate the pre-test probability of malignancy using the Swensen model and the Herder model. The probability of malignancy was classified as low if < 5%, intermediate if 5-65%, and high if > 65%. Cases classified as intermediate in the Swensen model were reclassified by the Herder model.

Results

We reviewed the records for 33 patients, of whom 17 (51.5%) were male. The mean age was 68.63 ± 12.20 years. According to the Swensen model, the probability of malignancy was intermediate in 23 cases (69.7%). Among those, the application of the Herder model resulted in the probability of malignancy being reclassified as low in 6 (26.1%) and as high in 8 (34.8%).

Conclusion

¹⁸F-FDG-PET/CT was able to modify the probability of malignancy classification of a solitary pulmonary nodule in more than 50% of the cases evaluated.

Agreement between diagnostic imaging methods for the evaluation of lymphadenopathies in HIV-infected/AIDS patients

Objective

To assess the percent agreement between diagnostic imaging modalities for the evaluation of lymphadenopathies in HIV-infected/AIDS patients.

Materials and Methods

This was an open, comparative, prospective study of diagnostic imaging methods for lymphadenopathy evaluation. We evaluated 30 patients (19 men and 11 women). All underwent ultrasound and computed tomography (CT). Twenty of the patients also underwent magnetic resonance imaging (MRI). We determined the percent agreement between two examiners using the various imaging methods to evaluate lymphadenopathies.

Results

CT had the highest percent agreement, at 93.3%, with a kappa coefficient of 0.85, corresponding to 28 of the 30 examinations. When we compared the percent agreement between the two examiners and between CT and ultrasound, examiner 1 had an observed rate of 80.0%, with a kappa of 0.49, corresponding to 24 of the 30 examinations, whereas examiner 2 had a rate of 70.0%, with a kappa of 0.31, corresponding to 21 of the 30 examinations. Between MRI and CT, the percent agreement for examiner 1 was 50.0%, with a kappa of −0.18, corresponding to 10 of the 20 examinations, whereas that for examiner 2 was 85.0%, with a kappa of 0.69, corresponding to 17 of the 20 examinations. For MRI and ultrasound, examiner 1 had a percent agreement of 70.0%, with a kappa of 0.20, corresponding to 14 of the 20 examinations, and examiner 2 had a percent agreement of 75.0%, with a kappa of 0.38, corresponding to 15 of the 20 examinations.

Conclusion

This study indicates that intermethod agreement is highly dependent on the way in which the research is conducted, rather than on the level of experience of the examiner.