Interobserver variability, and visual and quantitative parameters of 123I-FP-CIT SPECT (DaTSCAN) studies

Objective To evaluate the degree of interobserver agreement in the visual interpretation of 123I-FP-CIT studies and to investigate for potential associations between visual and semi-quantitative parameters. Methods Eighty-nine 123I-FP-CIT studies were blindly reviewed by 3 independent observers: a consultant, a resident doctor and a radiographer. They classified every study as either "normal" or "abnormal" and assigned visual 123I-FP-CIT uptake scores (2: normal, 1: reduced and 0: no uptake) in basal ganglia nuclei (right and left putamina and caudate nuclei) on every scan. Striatal 123I-FP-CIT binding ratios were calculated using crescent- ROI software. The interobserver agreement for the interpretation of studies and for visual score assignment was evaluated by means of κ statistics. We investigated for associations of binding ratios with visual scores and clinical parameters; patients' clinical diagnoses served as the reference standard. Results There was excellent interobserver agreement (j 0.89-0.93) in classifying studies as "normal" or "abnormal" and fine agreement in assignment of visual scores (j 0.71-0.80 for putamina and 0.50-0.79 for caudate nuclei). Nuclei with scores of 1 and 0 showed significantly reduced binding ratios (about 30 and 50%, respectively) compared with the nuclei scored as 2. ROC analysis indicated the optimal cutoff point of striatal binding ratio at 3.8 (sensitivity 98.5%, specificity 95%) for the detection of parkinsonian syndromes. Striatal binding ratios were negatively associated with age in normal subjects and disease duration in Parkinson's disease patients. Conclusion Visual interpretation of 123I-FP-CIT studies showed very good interobserver agreement. We found significant associations among visual, semi-quantitative and clinical parameters. © The Japanese Society of Nuclear Medicine 2012

A Reappraisal of the Utility of Somatostatin Receptor Scintigraphy in Patients with Ectopic Adrenocorticotropin Cushing's Syndrome

Ectopic ACTH hypersecretion is a rare cause of Cushing's syndrome. Bronchial carcinoids are the most common neoplasms causing the occult ectopic ACTH syndrome (EAS). Localization of these tumors is often difficult. The diagnostic utility of somatostatin receptor scintigraphy (SRS) in EAS has been studied in a limited number of patients with conflicting results. Herein we report our experience with 12 consecutive cases. Histological confirmation was obtained in nine patients, the majority being bronchial carcinoids. Among the seven patients with histologically confirmed bronchial carcinoids, SRS was performed in six patients. In three patients SRS correctly localized a bronchial carcinoid tumor at presentation. In the remaining three it became positive after 8, 22, and 27 months during follow-up. In two patients SRS was positive without any finding in the corresponding conventional imaging study. In two patients positive computed tomography/magnetic resonance imaging preceded SRS localization. There was no false positive SRS. Among three patients with highly suspected EAS, SRS was positive in one. Both patients with EAS due to medullary thyroid carcinoma had focal positive uptake. In summary, in this study a substantial number of patients had positive tumor localization by SRS. Therefore, SRS is a useful tool in the evaluation of patients with EAS

Long-term outcome of differentiated thyroid cancer in children and young adults: risk stratification by ATA criteria and assessment of pre-ablation stimulated thyroglobulin as predictors of disease persistence

Purpose: Differentiated thyroid cancer (DTC) has an increasing incidence in childhood and adolescence but long-term outcome data are limited. We aimed to identify possible risk factors associated with disease persistence, with special focus on the usefulness of ATA risk stratification system and pre-ablation stimulated thyroglobulin (Tg) levels. Methods: We retrospectively studied 103 patients, 79 females (76.7%), aged 15.6 ± 3.2 years (range 5–21 years) who underwent total thyroidectomy for DTC. Patients were classified by ATA risk stratification criteria as low, intermediate, and high risk for recurrence. All, except five with papillary microcarcinoma, received radioactive iodine (RAI) treatment. Results: At diagnosis, 44.7% of patients had cervical lymph node and 7.8% pulmonary metastases. Amongst the 72 patients with long-term follow-up data, 31.9% had persistent disease. Lymph node as well as pulmonary metastases and increased pre-ablation stimulated thyroglobulin (Tg) levels were associated with persistent disease. The risk of persistent disease was significantly higher in both the intermediate- (OR 17.95; 95% CI 2.66–120.94, p < 0.01) and high-risk (OR 17.65; 95% CI 4.47–69.74, p < 0.001) groups. ROC curve analysis showed that a pre-ablation Tg level higher than 14 ng/ml had a sensitivity of 94.7% to predict persistence, corresponding to a positive (PPV) and negative predictive values (NPV) of 66.7% and 93.8%, respectively. Conclusions: ATA risk stratification was validated in our population of children and young adults with DTC. Moreover, pre-ablation stimulated Tg levels of <14 ng/ml were associated with a low risk of long-term persistence and may therefore serve as a marker to identify patients who may need less intensive surveillance. © 2020, Springer Science+Business Media, LLC, part of Springer Nature

A Unique Case of Primary Extranodal Marginal Zone Lymphoma of the Anal Canal

Marginal zone lymphomas represent approximately 10-12% of all B-cell lymphomas. Extranodal marginal zone lymphomas (EMZL) or mucosa-associated lymphoid tissue (MALT) lymphomas are the most common subtype. Almost half of all MALT lymphomas arise in the gastrointestinal (GI) tract and, while the stomach is the most common site of GI involvement, the small and large intestines can also be involved. Rare cases of MALT lymphoma involving the rectum have been reported; however, to our knowledge, involvement of the anal canal has never been reported in the literature. Here, we describe a unique case of MALT lymphoma of the anal canal. Infectious agents have been implicated in the pathogenesis of MALT lymphomas, possibly through persistent antigenic stimulation of the area; however, in our case no such infection was documented. © 2019 S. Karger AG, Basel. All rights reserved

Positron emission tomography after response to rituximab-CHOP in primary mediastinal large B-cell lymphoma: impact on outcomes and radiotherapy strategies

End-of-treatment (EoT) PET/CT is used as a guide to omit radiotherapy (RT) patients with primary mediastinal large B-cell lymphoma (PMBCL). We present the mature and extended results of a retrospective study evaluating the prognostic significance of EoT-PET/CT after adequate response to R-CHOP. Among 231 consecutive PMLBCL patients, 182 underwent EoT-PET/CT and were evaluated according to the Deauville 5-point scale (D5PS) criteria. Freedom from progression (FFP) was measured from the time of PET/CT examination. Among 182 patients, 72 (40%) had D5PS score 1 (D5PSS-1), 33 (18%) had 2, 28 (15%) had 3, 29 (16%) had 4, and 20 (11%) had 5. The 5-year FFP was 97, 94, 92, 82, and 44% for D5PSS-1, D5PSS-2, D5PSS-3, D5PSS-4, and D5PSS-5, respectively. Among 105 patients with unequivocally negative PET/CT (D5PSS-1/D5PSS-2), 49 (47%) received RT (median dose 3420 cGy) and 56 (53%) did not with relapses in 0/49 vs. 4/56 patients (2 mediastinum and 2 isolated CNS relapses).The 5-year FFP for those who received RT or not was 100% versus 96%, when isolated CNS relapses were censored (p = 0.159). Among D5PSS-3 patients (27/28 irradiated-median dose 3600 cGy), the 5-year FFP was 92%. The 5-year FFP for D5PSS-4 and D5PSS-5 was 82 and 44%; 44/49 patients received RT (median dose 4000 and 4400 cGy for D5PSS-4 and D5PSS-5). Our study supports the omission of RT in a sizeable fraction of PET/CT-negative patients and definitely discourages salvage chemotherapy and ASCT in patients with PMLBCL who conventionally respond to R-CHOP, solely based on PET/CT positivity in the absence of documented progressive or multifocal disease. The persistence of positive PET/CT with D5PSS < 5 after consolidative RT should not trigger the initiation of further salvage chemotherapy in the absence of conventionally defined PD. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature

Positron emission tomography after response to rituximab-CHOP in primary mediastinal large B-cell lymphoma: impact on outcomes and radiotherapy strategies

End-of-treatment (EoT) PET/CT is used as a guide to omit radiotherapy (RT) patients with primary mediastinal large B-cell lymphoma (PMBCL). We present the mature and extended results of a retrospective study evaluating the prognostic significance of EoT-PET/CT after adequate response to R-CHOP. Among 231 consecutive PMLBCL patients, 182 underwent EoT-PET/CT and were evaluated according to the Deauville 5-point scale (D5PS) criteria. Freedom from progression (FFP) was measured from the time of PET/CT examination. Among 182 patients, 72 (40%) had D5PS score 1 (D5PSS-1), 33 (18%) had 2, 28 (15%) had 3, 29 (16%) had 4, and 20 (11%) had 5. The 5-year FFP was 97, 94, 92, 82, and 44% for D5PSS-1, D5PSS-2, D5PSS-3, D5PSS-4, and D5PSS-5, respectively. Among 105 patients with unequivocally negative PET/CT (D5PSS-1/D5PSS-2), 49 (47%) received RT (median dose 3420 cGy) and 56 (53%) did not with relapses in 0/49 vs. 4/56 patients (2 mediastinum and 2 isolated CNS relapses).The 5-year FFP for those who received RT or not was 100% versus 96%, when isolated CNS relapses were censored (p = 0.159). Among D5PSS-3 patients (27/28 irradiated-median dose 3600 cGy), the 5-year FFP was 92%. The 5-year FFP for D5PSS-4 and D5PSS-5 was 82 and 44%; 44/49 patients received RT (median dose 4000 and 4400 cGy for D5PSS-4 and D5PSS-5). Our study supports the omission of RT in a sizeable fraction of PET/CT-negative patients and definitely discourages salvage chemotherapy and ASCT in patients with PMLBCL who conventionally respond to R-CHOP, solely based on PET/CT positivity in the absence of documented progressive or multifocal disease. The persistence of positive PET/CT with D5PSS < 5 after consolidative RT should not trigger the initiation of further salvage chemotherapy in the absence of conventionally defined PD. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature