Page 48 - World Association of Laparoscopic Surgeons - Journal

WJOLS

The Role of Thoracoscopy in Diagnosis and Treatment of Pleural Disease

In exudative pleural effusions due to tuberculosis, the of mesothelioma, so an unnecessary thoracotomy can be
diagnostic yield of a closed needle biopsy is 70 to 90%. avoided.
Thoracoscopy is usually unnecessary, therefore, to establish
the diagnosis of a tuberculous effusion. A combined yield Parenchymal Disease
of only 6% for thoracoscopy preceded by negative
Ultimately, one-third of patients with diffuse lung disease
thoracentesis and closed needle pleural biopsy has been 32
will undergo open biopsy to establish a diagnosis. Open
reported. Thoracoscopy may be beneficial in difficult lung biopsy has an operative mortality of 1.7% and risk for
diagnostic situation, however, when lysis of adhesions is serious morbidity of 2.5% in selected patients. 14,33
necessary, or when larger amounts of tissue are warranted
Thoracoscopic lung biopsy has been proposed as an
to assure diagnosis when drug resistance is suspected.
alternative to open biopsy when bronchoscopic
Malignant mesothelioma: Although malignant mesothelioma transbronchial biopsy specimens are indeterminate.
may be suspected based on a history of asbestos exposure, Thoracoscopy, as opposed to bronchoscopy, can obtain
symptoms, radiographic findings of pleural fluid, larger pieces of lung tissue under direct visualization.
thickening, absence of contralateral shift of the In addition, it provides tissue for mineralogic studies of
mediastinum, and clinical course; diagnostic confirmation the pneumoconioses, and for diagnosis of pulmonary
is often difficult. The diagnosis of mesothelioma depends infiltrates or peripheral nodular lesions of unknown etiology.
foremost on histologic findings. 29 Pleural fluid cytology Specimens are usually obtained using an endoscopic stapling
ranges from 4 to 77%, and representative specimens from device. VATS is now another alternative to open lung
closed needle biopsy are rarely of sufficient size and number biopsy. Various nonrandomized studies have investigated
to allow the full battery of immunohistochemical stains and the VATS approach for lung biopsy. Bensard et al 36
electron microscopic examination for definitive diagnosis. 7 retrospectively analyzed 22 consecutive patients with
Obtaining definitive biopsy samples for the diagnosis of interstitial disease who underwent VATS lung biopsy and
mesothelioma is a main indication for thoracoscopy. Even compared then with 21 control patients who underwent open
with thoracoscopy, the accuracy of diagnosing biopsy. They concluded that VATS (1) provided equivalent
mesothelioma may suffer because of inadequate specimen volume, (2) achieved equal diagnostic accuracy,
visualization due to extensive adhesions and the inherent and (3) reduced both the time for pleural drainage and the
difficulties in pathologic identification of this tumor. 8 length of hospital stay. Ferson et al 37 retrospectively
Thoracoscopy allows removal of large, full-thickness compared 47 patients who underwent VATS lung biopsy
specimens from several involved areas, making it potentially with 28 historical control patients who underwent open
preferable to open pleural biopsy by minithoracotomy, and wedge biopsy via limited thoracotomy. The mean operative
most certainly preferable to lateral thoracotomy. For patients time was significantly longer in the VATS group (69 vs
not considering intrapleural chemotherapy or surgical 93 minutes respectively), but there were significantly more
resection, pleurodesis can be performed at the time of complications in the open group (including more bleeding
diagnostic thoracoscopy in order to prevent fluid and prolonged air leaks). The duration of hospital stay was
reaccumulation and to delay the onset of life-threatening shorter in the VATS group (mean, 4.9 to 12.2 days).
dyspnea. Although tumor growth through thoracoscopic The above studies suggest that VATS lung biopsy is an
9
incision sites has been described, it is probably less frequent alternative to open biopsy. VATS lung biopsy is suitable
than reported. Prevention is possible by treating the area for patients in stable condition who are not requiring
surrounding the incision sites with radiation. Boutin et al 30 mechanical ventilation. Ventilator-dependent patients
recently reviewed the results of simple rigid thoracoscopy should not undergo biopsies by the VATS approach because
in 153 patients with malignant mesothelioma. The main they typically cannot tolerate the change to a double-lumen
indications were chronic pleurisy (88%) and radiologically endotracheal tube or the single-lung ventilation technique.
detected pleural densities (9%). One quarter of the patients For patients requiring mechanical ventilation in most cases,
required electrocautery or laser to lyse adhesions. it is advisable to perform an open lung biopsy through an
Thoracoscopic biopsy specimens were positive in 150 of expeditious limited thoracotomy using minimal rib
153 (98%) mesothelioma cases. In contrast, the combined spreading.
sensitivity of pleural cytologic study and closed needle A solitary pulmonary nodule (SPN) is a discrete nodule
biopsy was only 38%. Thoracoscopy provides equally good less than 3 cm in diameter that is completely surrounded by
tissue samples for diagnosis of mesothelioma compared with lung and is not associated with parenchymal disease or
31
thoracotomy? Thoracoscopy also allows accurate staging adenopathy. 40 Over 80 different causes have been
World Journal of Laparoscopic Surgery, January-April 2012;5(1):4-15 7