Efficacy and safety of thoracoscopic cryobiopsy in patients with undiagnosed exudative pleural effusion

Background
Pleural effusions are either transudate or exudate according to the biochemical analysis of aspirated pleural fluid. Thoracentesis or blind pleural biopsy may not provide a definitive diagnosis. Cryobiopsy has more successful diagnostic results than forceps biopsies with complications (only hemorrhage) during procedures. Cryobiopsy can obtain more diagnostic biopsies due to the size of the biopsies and best property in expressions of an artifact-free sample area.


Results
This prospective intervention study was conducted on 51 patients who were divided randomly into two groups according to the biopsy technique: Group I (cryobiopsy group): 26 patients where patients will be subjected to thoracoscopic cryobiopsy. Group II (forceps group): 25 patients where patients will be subjected to thoracoscopic forceps biopsy. To demonstrate the efficacy and safety of taking biopsy specimens from parietal pleura in undiagnosed exudative pleural effusion. In the present study, the most common thoracoscopic finding was pleural nodules in 17 (65.4%) patients of cryobiopsy and 13 (53%) patients of forceps biopsy. The mean size in cryobiopsy was 14±4.2 mm, while in forceps biopsy, it was 5±0.6 mm. The most common pathological type of malignancy was the metastatic adenocarcinoma in 30 (58.8%) patients. The diagnostic yield of rigid medical thoracoscopy was 100% in both groups. Cryobiopsy was easily interpretable in the current study as focal and diffuse hemorrhage and crush artifact/atelectasis is less in biopsy. All procedures were generally well-tolerated by the patients in both groups, cryobiopsy was a painless procedure, while forceps biopsy was registered pain in 12 (48%) patients.


Conclusions
Cryobiopsies of the pleura using medical rigid thoracoscopy represent a safe and painless method to take biopsy and an effective tool to obtain larger tissue samples with a safe cellular architecture.