Speaker's Highlight

• Don Sin University of British Columbia, St. Paul Hospital (Canada)
  Kenneth R. Chapman Toronto General Hospital Research Institute (Canada)
• Parameswaran Nair McMaster University (Canada)
  Carolyn Calfee UCSF (U.S.A.)
• Gregory P. Downey University of Colorado School of Medicine (U.S.A.)
  David A. Schwartz University of Colorado School of Medicine (U.S.A.)
• Neil Schluger Tuberculosis Control Branch, California Department of Public Health (U.S.A.)
  Nick Kim Critical Care & Sleep Medicine, University of California San Diego (U.S.A.)
• Nicola Hananiah Baylor College of Medicine (U.S.A.)
  Jae-Joon Yim Seoul National University College of Medicine (Republic of Korea)
• Koichiro Asano Tokai University School of Medicine (Japan)
  Diahn-Warng Perng Taipei Veterans General Hospital (Taiwan)
• Konstantinos Kostikas University of Ioannina (Greece)
  Karin Klooster University Medical Center Groningen (Kingdom of the Netherlands)

• Diagnostic Yield of Radial Probe EBUS for Peripheral Lesions

  Peripheral pulmonary lesions are frequently beyond the reach of a standard bronchoscope. A respiratory physician may therefore need a minimally invasive method that can visualise the lesion, locate its airway, obtain tissue and distinguish malignant disease from infection, inflammation or a benign granuloma before committing a patient to surgery.

  The diagnostic yield of radial probe endobronchial ultrasound for peripheral lesions is the proportion of attempted procedures that provide a diagnosis adequate for clinical decision-making. Reported rates vary markedly, commonly falling around 60–80% in selected series, while some specialist centres report higher results. Yield should be read alongside lesion characteristics, pre-test probability and the consequences of missed cancer.

  Why an accurate diagnosis matters

  A peripheral pulmonary nodule may represent primary lung cancer, a metastasis, an infection or an inflammatory process. Tissue confirmation can prevent unnecessary surgery, guide systemic treatment or allow a patient with benign disease to enter appropriate surveillance. A precise diagnosis is especially valuable when an operation would involve substantial removal of lung tissue.

  Yield is not identical to accuracy. A procedure may retrieve tissue without establishing malignancy, while a high cancer prevalence can make malignancy prediction appear more accurate. Clinical probability, imaging findings and the consequences of residual diagnostic uncertainty must therefore be considered. Australia’s longstanding tobacco-control measures, including taxation and plain packaging, have reduced smoking, but lung cancer risk remains relevant in older adults and certain communities.

  How radial probe EBUS is performed

  Radial probe EBUS, often called RP-EBUS, uses a small radial ultrasound miniprobe passed through a guide sheath and working channel of a bronchoscope. Real-time radial images help the operator determine whether the probe is within the lesion, adjacent to it or outside it. Once a suitable position is identified, the probe can be withdrawn while the guide sheath maintains access for biopsy forceps, brushes or aspiration tools.

  Most procedures are performed under moderate sedation with local anaesthetic, although anaesthetic selection depends on the patient and centre. Ultrasound findings guide where instruments are passed, while careful bronchoscopic inspection also identifies visible mucosal abnormalities. For equipment familiarisation, the linked procedural reference can complement local simulation, supervised training and credentialing.

  What determines diagnostic yield

  Lesion size is a major predictor. Smaller lesions, particularly those around or below 20 millimetres, provide less material for sampling and may lie several airway generations from the visible bronchus. Yield can also be reduced by extensive necrosis, surrounding fibrosis, a cavity or a position close to the chest wall. Upper-lobe lesions may be harder to reach because of acute airway angles.

  Operator skill, imaging quality and procedural planning matter equally. The team must identify a viable bronchus leading towards the target, maintain access and obtain several samples without repeatedly missing the lesion. Fluoroscopy or navigation technology may help when the lesion is not visible on ultrasound, although these tools have their own limitations. On-site cytology and pathology support can shorten the interval to a definitive result.

  Interpreting findings and evidence

  RP-EBUS can assist malignancy prediction: an image showing a lesion or adjacent structure may raise suspicion, but pathological confirmation remains central to diagnosis. Even when no malignant cells are found, the sample may identify infection or inflammation. Conversely, a nondiagnostic sample containing only necrotic material does not exclude cancer.

  Studies must be interpreted carefully because reported yield, sensitivity and specificity describe different outcomes. The value of a negative result depends heavily on cancer prevalence, lesion selection and sample adequacy. Much of the evidence comes from referral populations at expert centres, limiting direct application to every community setting. A negative procedure should be reconciled with CT findings and clinical risk, with an agreed plan for further assessment.

  Delivery across Australian health services

  Tertiary respiratory and interventional bronchoscopy services are concentrated in major cities such as Sydney, Melbourne, Brisbane, Perth and Adelaide. Patients from rural or remote areas may need coordinated travel, sometimes with extended waits for a procedural slot. Local specialists can help determine whether referral is appropriate, whether preliminary investigations are complete and whether transfer to a higher-volume centre should be considered.

  Australia has a mixed public and private health market. Public patients generally access hospital treatment through public services, while privately insured patients may choose an interventional pulmonologist in a hospital. General practitioners and respiratory physicians determine referral pathways, and eligible consultations may attract Medicare rebates. Device regulation is overseen by the Therapeutic Goods Administration, which is relevant when centres acquire radial probes and accessories.

  Consent and information handling must also meet Australian expectations, including obligations under the Privacy Act 1988 and applicable health-service codes. In a culturally and linguistically diverse population, qualified interpreters can be essential for explaining sedation, sampling limitations and possible complications. Clear documentation supports both continuity of care and responsible follow-up when the initial result is inconclusive.

  RP-EBUS is most useful when imaging shows a reachable peripheral lesion and the result could change management. High yield depends on selecting suitable patients, reaching the target confidently, sampling it thoroughly and integrating pathology with the full clinical assessment.

  The finding to retain is that neither a reassuring image nor a negative sample can stand alone. Its value comes from combining technical precision, pathological evidence, knowledge of pre-test probability and a clear plan for any remaining diagnostic uncertainty.

  Richard Russell Nuffield Department of Clinical Medicine, University of Oxford (United Kingdom)
• Mona Bafadhel King’s College London (United Kingdom)
  David Jackson Guy’s and St Thomas’ Hospital, King’s College London (United Kingdom)
• James Chalmers University of Dundee (United Kingdom)
  David Price University of Aberdeen (United Kingdom)