Non-palpable Pulmonary Nodules and Uniportal-VATS: Radio-guided Localization (ROLL) Experience of a Lung Multidisciplinary Team.

BACKGROUND/AIM: Surgical resection with a minimally invasive approach is the standard for diagnosing and treating solitary pulmonary nodules. A computed tomography (CT)-guided technetium99m-macroaggregated albumin (99mTc-MAA) injection-based procedure has been employed for small and non-palpable lung nodule radio-guided preoperative localization (ROLL). This procedure is usually followed by video-assisted thoracoscopic surgery (VATS). This study retrospectively evaluated the feasibility, clinicopathologic outcomes, and complications of this localization radio-guided procedure followed by uniportal VATS. PATIENTS AND METHODS: This retrospective study included 63 patients with suspicious lung nodules who underwent 99mTc-MAA CT-guided localization before uniportal VATS. The analysis examined the imaging and procedure characteristics, procedural risks, successful intra-operative localization, wedge resection, conversion from VATS to open thoracotomy, the reason, and histological diagnosis for each nodule. Also, it was evaluated how nodule and procedure features affected successful intra-operative localization. RESULTS: All patients were diagnosed using a CT scan, and 90.4% had a PET scan at basal staging. A round-glass morphology was present in 9.6% of cases, whereas most had a solid appearance. The mean nodule size was 9.78 mm (maximal tumoral diameter) with a 1-23 mm range. The mean distance from the pleural surface was 15.6 mm (range=1-117 mm). The detection rate of the 99mTc-MAA CT-guided localization procedure was 100%. Surgical procedures were uniportal VATS and transpleural thoracoscopy in 52 (82.5%) and 11 (17.5%) patients, respectively. The intraoperative localization rate was 98.4%. Pneumothorax represented the most frequent complication (6.3%), with one case clinically significant and three only with minimal radiological evidence. Pathology confirmed radical excision in all cases. CONCLUSION: Lung nodule localization with CT-guided 99mTc-MAA followed by uniportal VATS is feasible with a high success rate and low complication rate.

mCRPC progression of disease after [177Lu]Lu-PSMA-617 detected on [18F]Choline: a case of PCa heterogeneity.

Radioligand therapy with [177Lu]Lu-PSMA is a theranostic approach for heavily treated mCRPC patients with positive PSMA PET in the absence of relevant PSMA-negative metastases assessed through CT, MRI, bone scan or FDG PET. In this case, we described a mCRPC patient treated with RLT with discordant PSA values and PSMA images, in which Choline PET confirmed a biochemically suspected disease progression (PD), showing metastatic lesions not revealed by PSMA imaging.

18 F-FET PET/CT in Calcifying Pseudoneoplasm of the Neuraxis : First Case.

ABSTRACT: A 66-year-old man has been treated in a psychiatric department for 4-5 years for a depressive syndrome, which is associated with poor motor initiative, confusional state, and dysosmia. Dynamic 18 F-FET PET/CT showed only faint uptake of radiotracer just above the background on the left frontal calcific lesion. The time-activity curve of the neoplasms showed a descending pattern. After a left fronto-orbitary minicraniotomy surgery, histology examination concluded for a rare calcifying pseudoneoplasm of the neuraxis (CAPNON). To our knowledge, no data are available on the metabolic behavior of CAPNON in 18 F-FET PET/CT. This case highlighted that a faint uptake and descending pattern on dynamic 18 F-FET PET/CT may be helpful in suspected CAPNON before surgery.

[68Ga]DOTATOC PET/CT Radiomics to Predict the Response in GEP-NETs Undergoing [177Lu]DOTATOC PRRT: The "Theragnomics" Concept.

Despite impressive results, almost 30% of NET do not respond to PRRT and no well-established criteria are suitable to predict response. Therefore, we assessed the predictive value of radiomics [68Ga]DOTATOC PET/CT images pre-PRRT in metastatic GEP NET. We retrospectively analyzed the predictive value of radiomics in 324 SSTR-2-positive lesions from 38 metastatic GEP-NET patients (nine G1, 27 G2, and two G3) who underwent restaging [68Ga]DOTATOC PET/CT before complete PRRT with [177Lu]DOTATOC. Clinical, laboratory, and radiological follow-up data were collected for at least six months after the last cycle. Through LifeX, we extracted 65 PET features for each lesion. Grading, PRRT number of cycles, and cumulative activity, pre- and post-PRRT CgA values were also considered as additional clinical features. [68Ga]DOTATOC PET/CT follow-up with the same scanner for each patient determined the disease status (progression vs. response in terms of stability/reduction/disappearance) for each lesion. All features (PET and clinical) were also correlated with follow-up data in a per-site analysis (liver, lymph nodes, and bone), and for features significantly associated with response, the Δradiomics for each lesion was assessed on follow-up [68Ga]DOTATOC PET/CT performed until nine months post-PRRT. A statistical system based on the point-biserial correlation and logistic regression analysis was used for the reduction and selection of the features. Discriminant analysis was used, instead, to obtain the predictive model using the k-fold strategy to split data into training and validation sets. From the reduction and selection process, HISTO_Skewness and HISTO_Kurtosis were able to predict response with an area under the receiver operating characteristics curve (AUC ROC), sensitivity, and specificity of 0.745, 80.6%, 67.2% and 0.722, 61.2%, 75.9%, respectively. Moreover, a combination of three features (HISTO_Skewness; HISTO_Kurtosis, and Grading) did not improve the AUC significantly with 0.744. SUVmax, however, could not predict the response to PRRT (p = 0.49, AUC 0.523). The presented preliminary "theragnomics" model proved to be superior to conventional quantitative parameters to predict the response of GEP-NET lesions in patients treated with complete [177Lu]DOTATOC PRRT, regardless of the lesion site.