Combined 18F-FDG PET-CT markers in dementia with Lewy bodies.

INTRODUCTION: 18F-Fluoro-deoxyglucose-positron emission tomography (FDG-PET) is a supportive biomarker in dementia with Lewy bodies (DLB) diagnosis and its advanced analysis methods, including radiomics and machine learning (ML), were developed recently. The aim of this study was to evaluate the FDG-PET diagnostic performance in predicting a DLB versus Alzheimer's disease (AD) diagnosis. METHODS: FDG-PET scans were visually and semi-quantitatively analyzed in 61 patients. Radiomics and ML analyses were performed, building five ML models: (1) clinical features; (2) visual and semi-quantitative PET features; (3) radiomic features; (4) all PET features; and (5) overall features. RESULTS: At follow-up, 34 patients had DLB and 27 had AD. At visual analysis, DLB PET signs were significantly more frequent in DLB, having the highest diagnostic accuracy (86.9%). At semi-quantitative analysis, the right precuneus, superior parietal, lateral occipital, and primary visual cortices showed significantly reduced uptake in DLB. The ML model 2 had the highest diagnostic accuracy (84.3%). DISCUSSION: FDG-PET is a valuable tool in DLB diagnosis, having visual and semi-quantitative analyses with the highest diagnostic accuracy at ML analyses.

DWI-MR and PET-CT Functional Imaging for Boost Tumor Volume Delineation in Neoadjuvant Rectal Cancer Treatment.

BACKGROUND/AIM: T2 weighted magnetic resonance (MR) imaging is the gold standard for locally advanced rectal cancer (LARC) staging. The potential benefit of functional imaging, as diffusion-weighted MR (DWI) and positron emission tomography-computed tomography (PET-CT), could be considered for treatment intensification strategies. Dose intensification resulted in better pathological complete response (pCR) rates. This study evaluated the inter-observer agreement between two radiation oncologists, and the difference in gross tumor volume (GTV) delineation in simulation-CT, T2-MR, DWI-MR, and PET-CT in patients with LARC. PATIENTS AND METHODS: Two radiation oncologists prospectively delineated GTVs of 24 patients on simul-CT (CTGTV), T2-weighted MR (T2GTV), echo planar b1000 DWI (DWIGTV) and PET-CT (PETGTV). Observers' agreement was assessed using Dice index. Kruskal-Wallis test assessed differences between methods. RESULTS: Mean CTGTV, T2GTV, DWIGTV, and PETGTV were 41.3±26.9 cc, 25.9±15.2 cc, 21±14.8 cc, and 37.7±27.7 cc for the first observer, and 42.2±27.9 cc, 27.6±16.9 cc, 19.9±14.9cc, and 34.8±24.3 cc for the second observer, respectively. Mean Dice index was 0.85 for CTGTV, 0.84 for T2GTV, 0.82 for DWIGTV, and 0.89 for PETGTV, representative of almost perfect agreement. Kruskal-Wallis test showed a statistically significant difference between methods (p=0.009). Dunn test showed there were differences between DWIGTV vs. PETGTV (p=0.040) and DWIGTV vs. CTGTV (p=0.008). CONCLUSION: DWI resulted in smaller volume delineation compared to CT, T2-MR, and PET-CT functional images. Almost perfect agreements were reported for each imaging modality between two observers. DWI-MR seems to remain the optimal strategy for boost volume delineation for dose escalation in patients with LARC.

Whole breast radiotherapy in cN0 early breast cancer patients with pathological sentinel lymph nodes (pN1mic, pN1a) without axillary dissection: preliminary results of the observational LISEN trial.

PURPOSE: Axillary management remains unclear when sentinel lymph node (SLN) results are positive in cN0 patients with breast cancer (BC). The trial ACOSOG Z0011 represented a revolution with axillary lymph node dissection (ALND) omission in SLN+ patients, despite critiques regarding non-uniformity of radiation fields. We conducted an observational study (LISEN) where whole breast radiotherapy (WBRT) was planned with tangential fields without nodal irradiation in patients eligible for the Z0011 trial. METHODS: Inclusion criteria were female patients with histologically proven BC, cT1-2cN0, planned conservative surgery, no neoadjuvant therapy. Patients were stratified into two groups: micrometastatic (pN1mic, group 1) and macrometastatic (pN1a, group 2) lymph nodes. Tangential field WBRT was mandatory. Clinical outcomes were analysed, measured from surgery until the first event. RESULTS: In all, 199 patients underwent conservative surgery and SLN biopsy; 133 patients meeting criteria were analysed: 41 patients (30.8%) pN1mic and 92 (69.2%) pN1a. The 5­year disease-free survival (DFS) was 95.0% (85.9-100%) in group 1 and 93.0% (86.3-100.0%) in group 2 (p = 0.78). Overall survival (OS) was 100% (100-100%) in group 1 and 97.4% (92.4-100%) in group 2 (p = 0.74). For the whole cohort DFS and OS were 93.6% (88.2-99.4%) and 96.9% (91.5-100.0%), respectively. For groups 1 and 2, the 5­year outcomes were 5.0% (0.0-14.4%) and 2.3% (0.0-6.1%) for local recurrence (p = 0.51), and 6.2% (0.0-17.4%) and 7.0% (0.0-13.7%) for distant metastasis (p = 0.61), respectively. In group 1, regional recurrence (RR) and local regional recurrence (LRR) were 5.0% (0.0-14.1%; p = 0.13). In group 2, RR and LRR were 0.0% (0.0-0.0%). CONCLUSION: Our results showed good regional control in patients who met the Z0011 trial criteria. WBRT, without nodal surgery or RT, avoiding axillary morbidity, seems to be a good choice.

Prevalence of interstitial pneumonia suggestive of COVID-19 at 18F-FDG PET/CT in oncological asymptomatic patients in a high prevalence country during pandemic period: a national multi-centric retrospective study.

PURPOSE: To assess the presence and pattern of incidental interstitial lung alterations suspicious of COVID-19 on fluorine-18-fluorodeoxyglucose positron emission tomography (PET)/computed tomography (CT) ([18F]FDG PET/CT) in asymptomatic oncological patients during the period of active COVID-19 in a country with high prevalence of the virus. METHODS: This is a multi-center retrospective observational study involving 59 Italian centers. We retrospectively reviewed the prevalence of interstitial pneumonia detected during the COVID period (between March 16 and 27, 2020) and compared to a pre-COVID period (January-February 2020) and a control time (in 2019). The diagnosis of interstitial pneumonia was done considering lung alterations of CT of PET. RESULTS: Overall, [18F]FDG PET/CT was performed on 4008 patients in the COVID period, 19,267 in the pre-COVID period, and 5513 in the control period. The rate of interstitial pneumonia suspicious for COVID-19 was significantly higher during the COVID period (7.1%) compared with that found in the pre-COVID (5.35%) and control periods (5.15%) (p < 0.001). Instead, no significant difference among pre-COVID and control periods was present. The prevalence of interstitial pneumonia detected at PET/CT was directly associated with geographic virus diffusion, with the higher rate in Northern Italy. Among 284 interstitial pneumonia detected during COVID period, 169 (59%) were FDG-avid (average SUVmax of 4.1). CONCLUSIONS: A significant increase of interstitial pneumonia incidentally detected with [18F]FDG PET/CT has been demonstrated during the COVID-19 pandemic. A majority of interstitial pneumonia were FDG-avid. Our results underlined the importance of paying attention to incidental CT findings of pneumonia detected at PET/CT, and these reports might help to recognize early COVID-19 cases guiding the subsequent management.

Embolization of Bleeding Pulmonary Arterial Pseudoaneurysm in a Woman With Infective Endocarditis.

Pulmonary arterial pseudoaneurysm is a rare but life-threatening complication of infective endocarditis. This report describes a case of bleeding pulmonary arterial pseudoaneurysm in a young, drug-addicted woman with tricuspid annuloplasty after infective endocarditis that was promptly identified by computed tomography pulmonary angiography and successfully treated using coil embolization. Perfusion scintigraphy at 30 days confirmed the safety of endovascular treatment.

Metastatic breast disease from cutaneous malignant melanoma.

INTRODUCTION: Malignant melanoma is one of the most rapidly increasing cancer in the world. Breast metastases from melanoma are uncommon but could reflect a widespread disease. PRESENTATION OF CASE: We report a case of malignant widespread melanoma presenting with bilateral breast nodules in a 39 year-old pre-menopausal Caucasian woman with an history of cutaneous melanoma of the trunk. Breast clinical examination revealed the presence of a hard and mobile lump located on the left breast. Ultrasound detected two bilateral nodules corresponding to oval opacities with well-defined edges and without calcifications or architectural distortion on mammography. Fine needle aspiration cytology performed on both breast nodules confirmed that the breast lesions were metastases from primary cutaneous malignant melanoma. A total-body CT examination detected brain, lung and abdominal lymph nodes metastases. DISCUSSION: The breast represents an uncommon site of metastatic disease from extra-mammary tumors. Imaging features of breast metastases from melanoma usually do not allow a differential diagnosis with breast primary tumors. Breast metastases may be asymptomatic or palpable as dense and well-circumscribed nodules. Breast metastases indicate a widespread disease and should lead to avoid aggressive surgical procedures because of the poor prognosis of patients affected by metastatic melanoma. CONCLUSION: The detection of bilateral breast metastases from melanoma is highly suggestive of metastatic multi-organ disease and could be useful to address the therapeutic approach.