Bronchoscopic procedures to diagnose peripheral lung lesions.

Bronchoscopy has a low risk of complications when diagnosing peripheral lung lesions suspected of malignancy, however the procedures do not always determine a diagnosis. Several modalities have been invented to improve the diagnostic yield, including radial endobronchial ultrasound and electromagnetic navigation, which are currently used by several departments in Denmark. Augmented fluoroscopy, CT-guided bronchoscopy and robotic bronchoscopy are not yet available in Denmark, but may improve the diagnostic work-up, as argued in this review.

Endoscopic ultrasound-guided pleural biopsy in the hands of the pulmonologist.

The use of the endobronchial ultrasound (EBUS) endoscope in the oesophagus, the so-called EUS-B procedure, for the diagnosis and staging of thoracic malignancy is quickly gaining ground. Pleural lesions located close to the oesophagus can be inaccessible to transthoracic biopsy and endoscopic procedures can be the only option. We here present two cases demonstrating that EUS-B-guided fine needle aspiration (EUS-B-FNA) of pleural lesions is possible. The first case demonstrates a EUS-B-FNA with malignant mesothelioma of a pleural lesion in a 70-year-old patient. In the second case, EUS-B-FNA diagnosed a pleural metastasis from adenoid cystic adenocarcinoma in a 75-year-old-patient. In conclusion, we hereby demonstrate that EUS-B-FNA from pleural lesions is feasible and appears to be safe.

The potential of 211Astatine for NIS-mediated radionuclide therapy in prostate cancer.

PURPOSE: We reported recently the induction of selective iodide uptake in prostate cancer cells (LNCaP) by prostate-specific antigen (PSA) promoter-directed sodium iodide symporter (NIS) expression that allowed a significant therapeutic effect of (131)I. In the current study, we studied the potential of the high-energy alpha-emitter (211)At, also transported by NIS, as an alternative radionuclide after NIS gene transfer in tumors with limited therapeutic efficacy of (131)I due to rapid iodide efflux. METHODS: We investigated uptake and therapeutic efficacy of (211)At in LNCaP cells stably expressing NIS under the control of the PSA promoter (NP-1) in vitro and in vivo. RESULTS: NP-1 cells concentrated (211)At in a perchlorate-sensitive manner, which allowed a dramatic therapeutic effect in vitro. After intraperitoneal injection of (211)At (1 MBq), NP-1 tumors accumulated approximately 16% ID/g (211)At (effective half-life 4.6 h), which resulted in a tumor-absorbed dose of 1,580+/-345 mGy/MBq and a significant tumor volume reduction of up to 82+/-19%, while control tumors continued their growth exponentially. CONCLUSIONS: A significant therapeutic effect of (211)At has been demonstrated in prostate cancer after PSA promoter-directed NIS gene transfer in vitro and in vivo suggesting a potential role for (211)At as an attractive alternative radioisotope for NIS-targeted radionuclide therapy, in particular in smaller tumors with limited radionuclide retention time.

Application of 188rhenium as an alternative radionuclide for treatment of prostate cancer after tumor-specific sodium iodide symporter gene expression.

CONTEXT: We reported recently the induction of iodide accumulation in prostate cancer cells (LNCaP) by prostate-specific antigen promoter-directed sodium iodide symporter (NIS) expression that allowed a significant therapeutic effect of (131)iodine ((131)I). These data demonstrated the potential of the NIS gene as a novel therapeutic gene, although in some extrathyroidal tumors, therapeutic efficacy may be limited by rapid iodide efflux due to a lack of iodide organification. OBJECTIVE: In the current study, we therefore studied the potential of (188)rhenium ((188)Re), as an alternative radionuclide, also transported by NIS, with a shorter half-life and higher energy beta-particles than (131)I. RESULTS: NIS-transfected LNCaP cells (NP-1) concentrated 8% of the total applied activity of (188)Re as compared with 16% of (125)I, which was sufficient for a therapeutic effect in an in vitro clonogenic assay. gamma-Camera imaging of NP-1 cell xenografts in nude mice revealed accumulation of 8-16% injected dose (ID)/g (188)Re (biological half-life 12.9 h), which resulted in a 4.7-fold increased tumor absorbed dose (450 mGy/MBq) for (188)Re as compared with (131)I. After application of 55.5 MBq (131)I or (188)Re, smaller tumors showed a similar average volume reduction of 86%, whereas in larger tumors volume reduction was significantly increased from 73% after (131)I treatment to 85% after application of (188)Re. CONCLUSION: Although in smaller prostate cancer xenografts both radionuclides seemed to be equally effective after prostate-specific antigen promoter-mediated NIS gene delivery, a superior therapeutic effect has been demonstrated for (188)Re in larger tumors.