Transbronchial needle aspiration. An underused diagnostic technique.
Despite its proven usefulness, TBNA is not widely used. An American College of Chest Physicians (ACCP) survey showed that only 11.8% of pulmonologists use TBNA. Most pulmonologists in the 1980s were not formally trained in TBNA. This lack of training has unfortunately translated to minimal emphasis on TBNA in current training programs in a large number of institutions. Technical problems with the procedure (faulty site selection, incomplete needle penetration, catheter kinking that prevents adequate suction, etc.), the confusing array of needles, low diagnostic yields, unproven concerns regarding the safety of the procedure, inadequate cytopathology support, and bronchoscopic damage have all perpetuated the image of limited usefulness for this procedure. Limitations to the practice of TBNA are: Lack of training during fellowship Technical inadequacies Lack of cytopathologists trained in TBNA interpretation Fear of bronchoscope damage Safety issues Failure to reproduce published successes Reservations regarding usefulness of TBNA results Hands-on experience with TBNA, developing familiarity and expertise with only a few needles, and paying careful attention to anatomy, procedure techniques, and specimen acquisition may all help to increase yield. The following lists how better results can be obtained with TBNA: Preprocedure Review TBNA instruction tapes Attend hands-on courses Practice with lung models Review patient's CAT scans Familiarize with one-two cytology and histology needle Obtain a trained assistant Procedural Identify target site Needle to airway angle at least greater than 45 degrees Insert entire length of the needle Use scope channel to support the catheter Release suction before withdrawing needle (for staging) Specimen acquisition Avoid delay in preparing slides Adequate sampling (at least two) Use smear method for cytology specimen Analyze all samples flush solutions cell block Postprocedure Find an experienced cytopathologist Review your procedure (by watching video) Review pathology slides Acquisition of skills with cytology needles should precede the use of the histology needle. Increasing education and experience can also increase diagnostic yields. Transbronchial needle aspiration has been proven to be accurate in staging lung cancers, identifying inoperable carcinomas, and diagnosing a variety of lung diseases. Few complications have been encountered and the technique is less invasive and less costly than surgical procedures. Drawing on evidence from published literature, we suggest the following guidelines for TBNA: All patients presenting with mediastinal or hilar adenopathy or both, should have 22-ga and/or 19-ga TBNA as the initial procedure. These procedures would help diagnose malignant and nonmalignant diseases, and stage lung cancers. All patients with evidence of submucosal and peribronchial disease should have 22-ga needle cytology sampling. In patients with visible endobronchial disease, 22-ga TBNA should be optional. In the presence of a necrotic or a hemorrhagic tumor, or in a patient with a bleeding diathesis, TBNA would be helpful. In all patients with Type III and IV peripheral nodules, TBNA should be the initial diagnostic procedure. There remains no doubt about the diagnostic usefulness of TBNA. Guidelines must be developed to ensure that pulmonary fellows are adequately trained in this procedure. Regional workshops with hands-on experience targeted to practicing pulmonologists organized by the ACCP would help popularize the procedure. Initial low yields should not discourage pulmonologists from using the procedure. Collaboration between thoracic surgeons, oncologists, and pulmonary physicians is essential to set up TBNA programs within institutions. With time, as more and more pulmonologists attain expertise in TBNA, the full potential of this nonsurgical, cost-effective, and safe procedure will be realized.
Dasgupta
A
A
Department of Pulmonary and Critical Care Medicine, Kelsey-Seybold Clinic, Houston, Texas, USA.
Mehta
A C
AC
D001707:Biopsy, Needle / Q000379:methods*; D001999:Bronchoscopy / Q000379:methods*; D006801:Humans; D008171:Lung Diseases / Q000175:diagnosis*