State of the art: pleuroscopy

Implementation of evidence on management of pleural diseases: insights from a territory-wide survey of clinicians in Hong Kong

BACKGROUND

Major advances in management of common pleural diseases have taken place in the past decade. However, pleural diseases are often managed by physicians of diverse training background and research on implementation of new knowledge is scanty. We aim to evaluate the practice pattern in pleural medicine among physicians in Hong Kong, for identification of possible gaps for clinical service improvement.

METHODS

The Hong Kong Thoracic Society undertook a cross-sectional questionnaire survey in 2019, targeting clinicians of various subspecialties in internal medicine and levels of experience (basic and higher trainees, specialists) from twelve regional hospitals of diverse service scopes throughout Hong Kong. Respondents were selected by non-probability quota sampling. The questionnaire tool consisted of 46 questions covering diagnostic and therapeutic aspects of common pleural diseases. The responses were anonymous, and analysed independently using SPSS statistics software.

RESULTS

The survey collected 129 responses, 47(36%) were from clinicians specialized in respiratory medicine. Majority of the respondents (98%) managed pleural diseases, including performing pleural procedures in their practice. Fifty-five percent of all the respondents had not received any formal training in transthoracic ultrasonography. A significant proportion of clinicians were unaware of pleuroscopy for investigation of exudative pleural effusion, indwelling pleural catheter for recurrent malignant pleural effusion, and combined intra-pleural Alteplase plus DNase for treatment of pleural infection (30%, 15% and 70% of non-respiratory clinicians respectively). Significant heterogeneity was found in the management of pleural infection, malignant pleural effusion and pneumothorax among respiratory versus non-respiratory clinicians. Contributing factors to the observed heterogeneity included lack of awareness or training, limited accessibility of drugs, devices, or dedicated service support.

CONCLUSION

Significant heterogeneity in management of pleural diseases was observed among medical clinicians in Hong Kong. Continuous medical education and training provision for both specialists and non-specialists has to be strengthened to enhance the implementation of advances, improve quality and equity of healthcare provision in pleural medicine.

Medical Thoracoscopy

Medical thoracoscopy is an effective and safe modality to visualize and sample contents of the pleural cavity. It is an outpatient procedure that can be performed while the patient is spontaneously breathing, with the use of local anesthesia and intravenous medications for sedation and analgesia. Medical thoracoscopy has indications in the management of a variety of pleural diseases. It is most commonly performed as a diagnostic procedure but has therapeutic applications as well. Although it has its advantages, management strategies of certain pleural diseases should take place within a multidisciplinary environment including general pulmonologists, interventional pulmonologists, and thoracic surgeons.

Review of the Physiology and Anesthetic Considerations for Pleuroscopy/Medical Thoracoscopy

Pleuroscopy or medical thoracoscopy is the second most common utilized procedure after bronchoscopy in the promising field of interventional pulmonology. Its main application is for the diagnosis and management of benign or malignant pleural effusions. Entry into the hemithorax is associated with pain and patient discomfort, whereas concurrently, notable pathophysiologic alterations occur. Therefore, frequently procedural sedation and analgesia is needed, not only to alleviate the patient's emotional stress and discomfort by mitigating the anxiety and minimizing the pain but also for yielding better procedural conditions for the operator. The scope of this review is to present the physiologic derangements occurring in pleuroscopy and compare the various anesthetic techniques and sedative agents that are currently being used in this context.

How to obtain adequate biopsy specımen in suspected thymic tumors

Pathologic diagnosis of thymic tumors (TTs) can be made by surgical or nonsurgical procedures. About 20% of TTs had been diagnosed by pretreatment biopsy methods while the rest had gone to surgery for diagnosis and treatment. However, in the last two decades there was an increase in pretreatment procedures for optimal management of locally advanced or metastatic TTs. Pretreatment tissue diagnosis of a noninvasive TT is not a standard option but is required if there is suspect or atypical clinical presentation and imaging, an invasive tumor requiring a nonsurgical approach or preoperative chemotherapy or chemo-radiotherapy, strong possibility of lymphoma or unclear differential diagnosis between lymphoma or other solid tumor by imaging studies, or suspicion of a metastatic lesion. In surgical diagnosis anterior mediastinotomy, video-assisted thoracic surgery or mediastinoscopy can be chosen for invasive TTs whereas total resection is performed for small, noninvasive tumors. Nonsurgical diagnosis can be made by transthoracic fine or core needle biopsies (TTFNA, TTCNB), conventional bronchoscopy, endobronchial ultrasonography-guided transbronchial needle aspiration (EBUS-TBNA), endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) or medical thoracoscopy depending on procedural amenability according to tumor extension. TTFNA and TTCNB have been the most frequently used nonsurgical methods. However, there is an upward trend in using conventional bronchoscopy, EBUS-TBNA, EUS-FNA and medical thoracoscopy recently. To increase the diagnostic performance of these procedures in TTs, recommendations are (I) obtaining histologic specimens, (II) combining smears or liquid based cytology preparations and cell blocks, (III) obtaining multiple sufficient samples, (IV) combining histologic and cytologic specimens, (V) performing morphologic, immunohistochemical and molecular analyses on all specimens, (VI) using rapid onsite evaluation for cytologic specimens, (VII) correlating pathologic, clinical and radiologic findings, (VIII) consulting experienced pathologists.

Medical thoracoscopy in the diagnosis of pleural disease: a guide for the clinician

INTRODUCTION

Developing a feasible and accurate means of evaluating pleural pathology has been an ongoing effort for over 150 years. Pleural fluid cellular and biomarker analyses are simple ways of characterizing and uncovering pathologic entities of pleural disease. However, obtaining samples of pleural tissue has become increasingly important. In cases of suspected malignancy and certain infections histopathology, culture, and molecular testing are necessary to profile diseases more effectively. The pleura is sampled via several techniques including blind transthoracic biopsy, image-guided biopsy, and surgical thoracotomy. Given the heterogeneity of pleural disease, low diagnostic yields, or invasiveness no procedural gold standard has been established in pleural diagnostics.

AREAS COVERED

Herein, we provide a review of the literature on medical thoracoscopy (MT), its development, technical approach, indications, risks, current and future role in the evaluation of thoracic disease. Pubmed was searched for articles published on MT, awake thoracoscopy, and pleuroscopy with a focus on reviewing literature published in the past 5 years.

EXPERT OPINION

As the proficiency and number of interventional pulmonologists continues to grow, MT is ideally positioned to become a front-line diagnostic tool in pleural disease and play an increasingly prominent role in the treatment algorithm of various pleural pathologies.

Pleuroscopy in 2013

Pleuroscopy provides a window to the pleural space while enabling biopsy of the parietal pleura under direct visual guidance for effusions of unknown etiology, guided chest tube placement, and pleurodesis for recurrent pleural effusions or pneumothoraces in selected patients. The procedure enjoyed resurgence when thoracic surgeons introduced the technique for video-assisted thoracic surgery (VATS). VATS is performed under general anesthesia with single-lung ventilation; pleuroscopy is performed in an endoscopy suite using nondisposable rigid or flex-rigid instruments, local anesthesia, and conscious sedation. Pleuroscopy is less invasive; in this review, we discuss the indications, complications, techniques, and recent advances in the procedure.

Diagnostic and predictive role of cell-free midkine in malignant pleural effusions

PURPOSE

The detection of circulating nucleic acids has long been explored for the diagnosis and prognosis of a variety of clinical conditions. The aim of this study was to detect the cell-free mRNA expression of midkine (MK) in patients with effusions and its potential diagnostic and predictive value.

METHODS

Effusions were collected prospectively from 168 patients. The cell-free RNA was extracted from effusions, and the mRNA expression of MK was detected using real-time PCR. The expression of carcinoembryonic antigen (CEA) and biochemical markers in effusions were also assayed. Primary cancer cells were isolated from the malignant effusions (n = 46). Compared with culture cell lines, the response of these cancer cells to chemotherapeutic agents was determined by CCK-8 assay.

RESULTS

The expression of cell-free MK mRNA was significantly higher in the malignant group than in the benign group (0.13 vs 0.01, P < 0.001). The sensitivity and diagnostic accuracy of MK were 77.5 and 81.5 %, while a combination of CEA and MK reached 86.9 % sensitivity and 88.7 % accuracy. In addition, cell-free MK mRNA expression was significantly correlated with inhibitory rate of cisplatin (R = -0.72, P < 0.01).

CONCLUSIONS

Measurement of cell-free MK mRNA levels in effusion supernatant yields a high diagnostic accuracy and a potential predictive value.

Outcome of patients diagnosed with fibrinous pleuritis after medical thoracoscopy

BACKGROUND

In patients with post- medical thoracoscopy histopathological diagnoses of fibrinous pleuritis, confusion can occur concerning subsequent procedures. This issue is particularly important in regions where mesothelioma is prevalent. We aimed to identify false negatives among patients where mesothelioma was common due to asbestos exposure whose histopathological diagnosis following thoracoscopy was fibrinous pleuritis. We also determined risk factors associated with patients that required additional advanced invasive procedures for diagnosis.

METHODS

Overall, 287 patients who underwent thoracoscopy were included in the study. Patients diagnosed with fibrinous pleuritis as a result of thoracoscopy were followed for 2 years regarding this condition. More invasive procedures were performed on patients who showed no recuperation or developed pleural disease again during the follow-up period.

RESULTS

Fibrinous pleuritis was observed in 101 (35.2%) patients. Follow-up of these patients revealed that the false negative rate was 18% for malignant pleural diseases. The thoracoscopist's opinion regarding the pleural space, computed tomography scan findings indicating malignancy, pain and female gender were determined to be risk factors for malignant pleural diseases.

CONCLUSIONS

In regions where mesothelioma is prevalent and one of the above-stated risk factors is present, patients whose post-thoracoscopy histopathological diagnosis is fibrinous pleuritis should be treated with a more advanced invasive diagnosis procedure.

Homemade talc spray atomizer dedicated to flexible-rigid pleuroscope

BACKGROUND

Thoracoscopic talc poudrage is the preferred technique for medical pleurodesis. However, commercial talc spray atomizers are not applicable with the flexible-rigid pleuroscope. Therefore, we developed a simple and cheap homemade talc spray atomizer dedicated to flexible-rigid pleuroscope.

OBJECTIVE

To describe the experience in performing talc poudrage using our homemade talc spray atomizer.

METHODS

A retrospective review was performed in 22 consecutive patients with symptomatic malignant pleural effusion undergoing thoracoscopic talc poudrage by our talc spray atomizer with the aim of performing a palliative pleurodesis.

RESULTS

Under direct flexible-rigid pleuroscopic guidance, we could instill talc throughout the pleural cavity with our talc spray atomizer in all cases. The median procedure time to instill the whole talc was 4 min 15 s. The successful pleurodesis was achieved in 77.3%.

CONCLUSIONS

We have introduced a homemade talc spray atomizer dedicated to the flexible-rigid pleuroscope. Uniform distribution of talc could be achieved without additional port placement.

Medical thoracoscopy

PURPOSE OF REVIEW

The technique and clinical applications of medical thoracoscopy have substantially evolved in the last few decades. The recent development of a semirigid thoracoscope, which is handled similarly to a bronchoscope, has made this procedure more attractive to pulmonologists. We will review the latest data on clinical applications, recently developed techniques, and safety of medical thoracoscopy, focusing mainly on its role in thoracic malignancies.

RECENT FINDINGS

Recent data confirm the high diagnostic yield of medical thoracoscopy - both with rigid and semirigid instruments - in detecting pleural metastases and determining the origin of pleural effusions. The degree of pleural adhesions found during thoracoscopy has been proposed by some authors as a prognostic factor for survival in patients with malignant pleural effusion. A large prospective multicenter study has established the safety of talc poudrage with large-particle talc, showing no cases of acute respiratory distress syndrome.

SUMMARY

Medical thoracoscopy is an excellent tool to establish diagnosis in patients with exudative pleural effusion of unclear origin. It is highly valuable in clarifying the origin of pleural effusions in patients with lung cancer, as the presence of a malignant pleural effusion is associated with poor survival and precludes the possibility of treatment with curative intention. Pleurodesis with talc poudrage is efficacious and well tolerated, especially with the use of large-particle talc.