Margherita Cattaneo

Background/Objectives: This study aimed to develop machine learning (ML) models to predict recurrence in thymoma patients using conventional and radiomic signatures extracted from preoperative [¹⁸F]FDG PET/CT. Methods: A total of 50 patients (25 males, 25 females; mean age 63.3 ± 14.2 years) who underwent thymectomy and preoperative [¹⁸F]FDG PET/CT between 2012 and 2022 were retrospectively analyzed. Radiomic analysis was performed using free-from-recurrence (FFR) status as a reference. Clinico-metabolic PET parameters were collected, and thymoma lesions were manually segmented on [¹⁸F]FDG PET/CT. A total of 856 radiomic features (RFts) were extracted from PET and CT datasets following IBSI guidelines, and robust RFts were selected. The dataset was split into training (70%) and validation (30%) sets. Two ML models (PET- and CT-based, respectively), each with three classifiers—Random Forest (RF), Support-Vector-Machine, and Tree—were trained and internally validated using RFts and clinico-metabolic signatures. Results: A total of 50 ROIs were selected and segmented. FFR was observed in 84% of our cohort. Forty-three robust RFts were selected from the CT dataset and 16 from the PET dataset, predominantly wavelet-based RFts. Additionally, three metabolic PET parameters were selected and included in the PET Model. Both the CT and PET models successfully discriminated against FFR after surgery, with the CT Model slightly outperforming the PET Model across different classifiers. The performance metrics of the RF classifier for the CT and PET models were AUC = 0.970/0.949, CA = 0.880/0.840, Precision = 0.884/0.842, Recall = 0.880/0.846, Specificity = 0.887/0.839, Sensitivity = 0.920/0.844, TP = 81.8%/83.3%, and TN = 92.9%/84.6%, respectively. Conclusions: ML-models trained on PET/CT radiomic features show promising results for predicting recurrence in patients with thymomas, which could be potentially applied in clinical practice for a better personalized treatment strategy.

The gold standard for histological acute cellular rejection diagnosis is transbronchial forceps biopsy (FB), but in recent years, transbronchial cryobiopsy (CB) has been increasingly used. This study aims to compare the diagnostic rate and safety of FBs and CBs performed in two different periods. We retrospectively reviewed our case history for the two biopsy procedures: 251 FBs (223 for surveillance purposes and 28 for clinical indication) and 218 consecutive CBs (159 for surveillance purposes and 59 for clinical indication). All biopsies were scored according to the ISHLT criteria. Diagnostic yield was higher in the CB group for all the parameters considered: a grade of acute rejection (AR) was detected in 95.0% vs. 84.5% in the CB vs. FB groups (p < 0.001). The diagnostic rate of airway inflammation was 65.1% vs. 51.8% (p = 0.005), and 89.0% vs. 64.9% (p < 0.001) for chronic rejection. Pneumothorax requiring chest drainage occurred in 4% of the CB group and 3% of the FB group. Moderate and severe bleeding complicated CB and FB procedures in seven (3%) and three cases (1%), respectively. Transbronchial cryobiopsies improved the diagnostic yield in the monitoring of the lung allograft. The complication rate did not increase significantly in CBs vs. FBs.

Background: The usefulness of ¹⁸FDG PET/CT scan in the evaluation of thymic epithelial tumours (TETs) has been reported by several authors, but data are still limited and its application in clinical practice is far from being defined. Methods: We performed a narrative review of pertinent literature in order to clarify the role of ¹⁸FDG PET/CT in the prediction of TET histology and to discuss clinical implications and future perspectives. Results: There is only little evidence that ¹⁸FDG PET/CT scan may distinguish thymic hyperplasia from thymic epithelial tumours. On the other hand, it seems to discriminate well thymomas from carcinomas and, even more, to predict the grade of malignancy (WHO classes). To this end, SUVmax and other PET variables (i.e., the ratio between SUVmax and tumour dimensions) have been adopted, with good results. Finally, however promising, the future of PET/CT and theranostics in TETs is far from being defined; more robust analysis of imaging texture on thymic neoplasms, as well as new exploratory studies with “stromal PET tracers,” are ongoing. Conclusions: PET may play a role in predicting histology in TETs and help physicians in the management of these insidious malignancies.

Background: Herein we report a case of thymectomy performed by bilateral hybrid RATS/VATS technique with the Versius Robotic System (CMR Surgical, Cambridge, UK) in a patient affected by thymoma with cystic-necrotic regression and chronic myeloid leukemia (CML) treated with Imatinib. Case Description: A 74-year-old woman was referred to our Centre in November 2021 for an occasional finding of anterior mediastinal masses detected by magnetic resonance imaging (MRI)-scan during regular follow-up for benign pancreatic cysts. The patient was asymptomatic, without any neurological signs of myasthenia gravis. She referred a previous history of thyroidectomy for multinodular goiter and CML, for which she assumed Levotiroxin and Imatinib. Computed tomography (CT)-scan confirmed the presence of a 5.5 cm left-sided dishomogeneous mediastinal mass and a 3 cm right paracardiac partially cystic lesion. Both masses had an increased fluorodeoxyglucose (FDG) uptake at the CT/positron emission tomography (PET)-scan with SUVmax 9.8 for the left lesion and SUVmax 3.6 for the right one. Therefore, the patient underwent surgical radical thymectomy with hybrid bilateral technique: we used the Versius Robotic System (three-port technique) for exeresis of the left masses and we performed a standard three-port thoracoscopy to complete the dissection of the second lesion on the right side. The procedure was uneventful. Only one left chest tube was positioned and then removed on the 3rd post-operative day. The patient was discharged on 4th post-operative day without any complications. Diagnosis: anatomopathological examination described the left mass as a 5.5×5.4 cm type B2 thymoma (cytokeratin AE1/AE3+, p40+, CD5−, CD117−, CD20−) with aspects (Conclusions: We validated our mini-invasive hybrid robot-assisted thoracoscopic surgery/video-assisted thoracoscopic surgery (RATS/VATS) technique as a feasible and safe surgical approach for complex anterior mediastinal lesions. Moreover, in this case, anatomopathological examination suggests an important role of Imatinib in the cystic-necrotic regression of thymoma; this finding could support further studies involving tyrosine kinase inhibitors (TKI) in the treatment of thymic neoplasms.

Non-intubated VATS for lung cancer—a focus on segmentectomy: a narrative review Cristina Diotti, Shehab Mohamed, Margherita Cattaneo, Francesco Damarco, Davide Tosi

In lung cancer accurate assessment of the mediastinal lymph node status is of paramount importance for the stage assignment as well as crucial for the therapeutic plan. TAC and positron emission tomography (PET) are valuable tools to achieve a preliminary picture of the mediastinal staging but Endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) is considered the first choice for investigating mediastinal lymph nodes as recommended by updated guide-lines. Despite the EBUS-TBNA sensitivity is satisfactory, it is not high enough to exclude mediastinal lymph node metastases; therefore devices and technologies were implemented to increase its sensitivity. The purpose of this narrative review is to describe the tools aimed at correctly interpreting sonographic patterns during EBUS and maximizing the diagnostic accuracy of TBNA. The bibliographic research identified 354 articles potentially related to the purpose of the current review and after accurate reading we selected 21 articles. Eight articles focused on the sonographic features of lymph nodes found during EBUS, 2 papers considered the Doppler patterns and, finally, 18 studies analyzed the advantages of ultrasound elastography. Sonographic features, vascular patterns and ultrasound elastography have proved to be helpful in directing the operator to biopsy the most suspect lymph node, especially in patients with CT-negative and/or PET-negative mediastinum.

The malignant pleural effusion is a common clinical issue, connected with metastatic tumors or with primary tumor of the pleura. This narrative review focuses on the video-assisted thoracic surgery (VATS) diagnostic approach and treatment modalities for management of malignant pleural effusion. We conducted searches for clinical studies and guidelines through Medline, Embase and Cochrane Library. Limiting the search to the last decade, we selected 29 papers: 5 randomized controlled trials, 9 prospective cohort studies, 11 retrospective studies, 3 guidelines and 1 survey. Malignant pleural effusion frequently affects the clinical evolution of patients with metastatic cancer and proper diagnosis in low risk patients is mandatory in the era of target therapy. Pleural biopsy, performed through pleuroscopy or VATS remains the gold standard for the diagnosis of malignant pleural effusion. The non-intubated VATS is a good combination of surgical skills and anaesthesiological management that could avoid risks of general anesthesia. The type and number of surgical access seems have no relevant impact on the short-term outcome. The best treatment to prevent the accumulation of pleural fluid remains the talc poudrage, possibly followed by talc slurry in case of recurrence.

Introduction: Diaphragmatic rupture (DR) is an acquired diaphragmatic defect that can cause herniation of abdominal organs into the chest. It is usually a trauma-related lesion, but rarely it can occur spontaneously. Every DR with abdominal herniation should be considered a surgical emergency. Presentation of case: A 61-year-old male patient, with previous exposure to asbestos, was diagnosed of Stage Ib malignant pleural mesothelioma (MPM). He underwent neo-adjuvant chemotherapy (three cycle of cisplatin-pemetrexed combination) and a cytoreductive surgery with pleurectomy/decortication. Post-operative course was characterized by prolonged air-leakage (PAL). After three months, during a follow-up CT-scan, a spontaneous diaphragmatic rupture (SDR) with gastric herniation was detected and treated by a laparascopic diaphragmatic repair and suture. Discussion: Spontaneous diaphragmatic rupture (SDR) is an extremely rare injury of the diaphragm (less than 1% of all DR). In this case, potential predisposing factors for SDR could be: presence of diaphragmatic “locus minoris resistentiae” due to thinning of the diaphragm and increase tissue fragility after neo-adjuvant chemotherapy and diaphragmatic pleural stripping; increased thoraco-abdominal pressure gradient due to PAL and residual pleural space. Thus, we confirmed the feasibility and safety of the laparoscopic approach. Conclusion: We highlight the multifactor etiopathology, the challenging diagnosis and the importance of a prompt treatment of SDR. Highlights: