Imaging-guided chest biopsies: techniques and clinical results
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This article aims to comprehensively describe indications, contraindications, technical aspects, diagnostic accuracy and complications of percutaneous lung biopsy.
Imaging-guided biopsy currently represents one of the predominant methods for obtaining tissue specimens in patients with lung nodules; in many cases treatment protocols are based on histological information; thus, biopsy is frequently performed, when technically feasible, or in case other techniques (such as bronchoscopy with lavage) are inconclusive.
Although a coaxial system is suitable in any case, two categories of needles can be used: fine-needle aspiration biopsy (FNAB) and core-needle biopsy (CNB), with the latter demonstrated to have a slightly higher overall sensitivity, specificity and accuracy.
Percutaneous lung biopsy is a safe procedure even though a few complications are possible: pneumothorax, pulmonary haemorrhage and haemoptysis are common complications, while air embolism and seeding are rare, but potentially fatal complications.
• Imaging-guided biopsy is one of the main methods to obtain lung nodule specimens.
• CT has the highest accuracy for diagnosis as an imaging guide.
• Compared to FNAB, CNB has a higher accuracy for diagnosis.
• Pneumothorax and parenchymal pulmonary haemorrhage care the most frequent complications.
• Several clinical and technical variables can affect diagnostic accuracy and patient safety.
KeywordsLung lesion Percutaneous biopsy Complication Diagnostic accuracy Fine-needle aspiration biopsy (FNAB) Core-needle biopsy (CNB)
Chest tumours, in particular lung cancer, remain one of the most common causes of cancer-related death worldwide. With the diffusion of spiral CT, an increasing number of lung and mediastinal lesions is detected and histological diagnosis is often necessary to determine the most appropriate management of these lesions . In this clinical scenario, imaging-guided biopsy is one of the main methods to obtain tissue specimens. Various imaging techniques including computed tomography (CT) fluoroscopy and ultrasound (US) can be used to guide chest biopsies, but CT is most frequently employed because of its high spatial and contrast resolution as well as its 3D imaging ability; in many cases CT is preferred based on the localisation of the nodule or other patient-related factors.
Indications for imaging-guided chest biopsy
Indications for imaging-guided chest biopsy
1. A new or enlarging solitary nodule or mass
2. Multiple nodules in a patient without known neoplastic disease or in prolonged remission
3. Focal parechymal infiltrates in which an infectious organism cannot be isolated
4. Diagnosis of hilar masses following negative broncoscopy
5. Undiagnosed mediastinal mass.
6. Bipopsy or re-biopsy of malignancy for targeted therapy.
A new or enlarging solitary nodule or mass
The increasing clinical use of chest CT has resulted in an increasing incidental detection of small pulmonary nodules. In particular, pulmonary nodules are incidentally detected in around 8.5% of the general population  and in up to 51% of subjects with risk factors . Therefore, a new or enlarging solitary nodule is the most common indication for imaging-guided chest biopsy. If a nodule is initially identified at conventional chest radiography, CT investigation is necessary to characterise the lesion, estimate the likelihood of malignancy  and identify lymphadenopathies or other accessible sites for biopsy (such as extra-thoracic metastases) [6, 7]. PET-CT examination may also be helpful in the management of pulmonary nodules larger than 1 cm, reducing the need of puncture of non-enhancing solid nodules [4, 5, 6, 7, 8] and with a sensitivity of 94% and a specificity of 83% for solid pulmonary nodules between 1 and 3 cm in diameter . It must be taken in consideration that active inflammation (i.e. active tuberculosis, histoplasmosis, rheumatoid nodules) may cause false positives on PET-CT scans because of their high glucose metabolism . On the other hand, low-grade malignant tumours, such as carcinoid  or low-grade adenocarcinoma , may produce false-negative results because of their low glucose metabolism. In these cases, careful follow-up with CT must be performed according to well-established guidelines to demonstrate regression/disappearance of the nodule after therapy or to address patients to biopsy if persistence or increase in size are evident .
Multiple nodules in a patient without known neoplastic disease or in prolonged remission
Several benign conditions can appear with slowly enlarging or multiple new pulmonary nodules, such as rheumatoid arthritis, sarcoidosis or infectious diseases, including tuberculosis and fungal infections, particularly in immunosuppressed patients [14, 15, 16]. In these cases appropriate clinical work-up and CT follow-up are sufficient to exclude malignancy. Nevertheless multiple nodular lesions may be the initial metastatic presentation in a patient with an unknown primary tumour or the sign of disease progression in a patient with known primary tumour in prolonged remission. In these cases imaging-guided biopsy may be necessary to confirm or exclude malignancy.
Focal parenchymal infiltrates in which an infectious organism cannot be isolated
When infectious organisms cannot be isolated from the culture of sputum, blood or lung lavage, lung biopsy can be necessary to obtain tissue samples for pathological examination. The biopsy sample can be cultured for diagnostic purposes to establish the most appropriate pharmacological treatment. Imaging-guided biopsy was demonstrated to have a sensitivity of 80% and a positive predictive value of 100% [17, 18].
Diagnosis of hilar masses following negative bronchoscopy
Transbronchial needle aspiration during bronchoscopy or under ultrasound guidance is still considered the reference technique for the diagnosis of hilar masses [19, 20]. However, when bronchoscopy cannot be performed or is inconclusive, hilar masses can be accurately diagnosed by imaging-guided biopsy.
Undiagnosed mediastinal mass
Mediastinal masses are most frequently located in the anterior mediastinum and include a variety of different entities, such as thymic malignancy, lymphomas, endocrine tumours and malignant germ cell tumours . In the absence of typical clinical and imaging features, histological diagnosis is necessary ; imaging-guided biopsy should be always attempted in accessible lesions before diagnostic mediastinoscopy or in case of inconclusive results of mediastinoscopy.
Biopsy or re-biopsy of malignancy for targeted therapy
Advanced non-small-cell lung cancer in progression after first-line therapy may need imaging-guided re-biopsy to detect a possible new biological profile and to guide therapeutic decision-making in more than one-third of cases. .
Abnormal values that should be corrected before the procedure
Patient management before procedures with moderate risk of bleeding
Correct to <1.5
Should be corrected for values >1.5 × control
Transfusion recommended for count <50.000/μl
Imaging guidance techniques
Furthermore, if a PET/CT is available, the needle should be led to the most enhancing area of the lesion to increase diagnostic accuracy.
Patient positioning and instruction
The patient should be positioned prone, supine or lying on the side, based on the previously planned access site and needle trajectory. When needed, arms can be raised above the head to widen the intercostal spaces and obtain easier access. The procedure should be adequately explained to the patients with emphasis on the potential stinging sensation during the pleural puncture and breath-hold phases.
Breath-hold techniques and needle manipulation
The breath-hold technique stabilises the positions of the diaphragm, pleural planes, lung, fissures and, ultimately, target lesions; however, breath-hold capabilities can be extremely different from patient to patient, and even the same subject may not be able to reproduce breath-hold during the procedure because of stress or fatigue. Therefore, it can be easier to target larger tumours (>2/3 cm) instructing the patient to breath freely with shallow respiration; even though the target lesions moves slightly, its large size may be sufficient to require few adjustments. In the remaining cases, the patient can be instructed to maintain an inspiratory or expiratory apnoea to allow easier access to target lesions.
Needle choice is based on the size and location of the lesion, intended needle trajectory, information expected from the pathologic sample, status of the lung parenchyma and operator preference. Some of the more commonly used fine-needle aspiration (FNA) devices include Chiba, Franseen, Westcott, MaxiCELL, Greene (Cook) and Turner (Cook) needles, which have circumferentially sharpened tips allowing for sampling. Core biopsy needles are designed to collect a small piece of tissue intended for surgical pathology analysis and can be designed as end-cutting or side-cutting devices. The most commonly used core biopsy needle is the Tru-Cut, which consists of an outer cutting cannula and an inner slotted stylet. The Temno core biopsy device is another similar commonly used automatic core biopsy needle. The Biopince full core is an automated end-cutting needle that produces a full cylindrical core specimen. The decision to perform core biopsy or both core biopsy and FNA is multifactorial and highly institution-/operator-dependent . The number of passes needed per procedure has not been defined, but the decision to perform more than one puncture depends on procedure difficulty, risk of complications, quality of the first specimen obtained and the pathologist’s requests. The presence of an on-site pathologist may reduce the number of biopsies needed . Also the use of a coaxial, a larger-bore needle that is kept in place to maintain access to the target lesion, may allow multiple tissue sampling, reducing repeated pleural or soft tissue punctures . Several techniques have been proposed to seal the path of the needle after its removal to reduce the risk of pneumothorax and haemorrhage; the most successful option is to create a blood patch with autologous venous blood [33, 34].
Ultrasound versus CT
Test characteristics for different imaging guidance techniques (ultrasound vs. CT), biopsy techniques (FNAB vs. core biopsy) and lesion location (pamediastinal vs. peripheral)
Imaging guidance techniqueE
Safety profile of imaging-guided biopsy
FNAB versus core biopsy
There is a wide variation in reporting diagnostic accuracies of fine-needle aspiration biopsy (FNAB) between different institutions, ranging from 64% to 97%. The false-negative rate of FNAB varies, occurring in 6 to 54% of biopsies. The sensitivity, specificity and accuracy of FNAB for pulmonary lesions are 82 to 99%, 86 to 100% and 64 to 97%, respectively . Core biopsy has been shown to have slightly higher overall sensitivity, specificity and accuracy, with respective values of 89%, 97% and 93% (Table 3). Several recent papers advocate the use of 18- and 20-gauge cutting needles as well as coaxial techniques to improve the diagnostic yield, reporting diagnostic accuracies of 74–95% for the diagnosis of malignancy. Charig and Phillips reported similar accuracy of FNAB and core biopsy when an on-site pathologist was available; in a similar setting Capalbo et al. observed a greater diagnostic accuracy of FNAB compared to core needle biopsy (94.83% vs. 81.82. %) . Nowadays, the test of genetic mutations is important to plan targeted therapies in patient with lung cancers. With regard to this point, Schneider et al. observed a statistically significantly higher number of samples sufficient for molecular testing in core biopsy than FNAB (67% vs. 46%; P = 0.007) .
Central versus peripheral lesions
Various studies evaluated the effects of lesion location on the diagnostic accuracy of imaging-guided biopsy in chest tumours. In a paper from Layfield et al. , the sensitivity in diagnosing lung tumours decreased from 100% in peripheral lesions to 82% in central lesions; however, this study was conducted in 1996 with basic CT equipment, as demonstrated by the striking differences in sensitivity between fluoroscopy guidance (97%) and CT guidance (80%). Yamagamy et al.  demonstrated that some peripherally located lesions are not accessible at all with conventional CT guidance because of their relationship with rib arcs, thus requiring needle positioning under CT-fluoroscopy guidance. Finally, Wang et al.  recently compared the rates of complications and diagnostic accuracy of CT-guided biopsy in peripheral versus paramediastinal lesions, demonstrating how this technique may be safe and reliable even for deeply located tumours; in particular, their paper reports diagnostic accuracy of 95.4% in paramediastinal lesions and 94.7% in peripheral lesions, with a sensitivity of 95.6% and 94.2% respectively (Table 3).
Post-procedural care and complications
Once the biopsy has been performed, a CT scan of the chest is obtained to identify any immediate post-procedural complications. According to some authors, the patients should be rolled over onto the punctured side to reduce the risk of delayed PNX; anyway, this is a controversial opinion, since other authors have reported no benefits of putting patients in the “biopsy down position” . Following measures include observation and monitoring of vital signs for at least 4 h. Chest films are usually acquired after 4 h to detect possible asymptomatic PNX. If the clinical suspicion of a PNX arises, chest radiography must be obtained immediately. In low-risk patients, many interventional radiology services reasonably perform lung biopsies on an outpatient basis, with discharge at 4 h and readmission only if symptoms develop .
Pulmonary haemorrhage and haemoptysis
Tumour seeding through the needle tract represents a very rare complication with a prevalence reported in the literature between 0.012 and 0.061% . The real clinical relevance is still discussed, but it is obvious that tumour seeding along the needle tract can significantly change patient management and life expectancy and should be strictly avoided . Tumour seeding is reported to be more frequently observed after imaging-guided core needle biopsy of pleural mesothelioma .
Complications by imaging guidance technique
In the meta-analysis from Di Bardino et al. US-guided biopsy was generally very well tolerated and safe, with a pooled incidence of PNX of 4.4% (22/503) in the reported papers. This looks favourable compared to CT-guided biopsy, but is also obviously correlated to a statistical bias in lesion position since the targets of US-guided biopsies are usually adjacent to or infiltrating the pleural surface, with a very low risk of PNX.
Compared with the conventional step-and-shoot approach for CT-guided biopsy, CT fluoroscopy is faster and requires fewer needle passes, resulting in a decrease of procedure duration and fewer complications. In particular Heck et al.  showed a trend toward a lower PNX rate when using CT fluoroscopy as guidance method. Similar results have been obtained by Kim et al. , with a decrease from 27.1% to 11.1% in PNX rates when using CT fluoroscopy.
In conclusion, imaging-guided chest biopsy is an interventional procedure of pivotal importance for several clinical conditions of pneumological, oncological and surgical interest. This procedure may appear very simple and linear, but radiologists approaching it for the first time must consider several clinical and technical variables significantly affecting the final results, in terms of both diagnostic accuracy and patients’ safety.
- 4.Momen M. Wahidi, Joseph A. Govert, Ranjit K. Goudar, et al. Evidence for the Treatment of Patients With Pulmonary Nodules: When Is It Lung Cancer? ACCP Evidence-Based Clinical Practice Guidelines (2nd Edition)Google Scholar
- 9.Gould MK, Maclean CC, Kuschner WG, Rydzak CE, Owens DK Accuracy of positron emission tomography for diagnosis of pulmonary nodules and mass lesions: a meta-analysis. JAMA 2001;21;285(7):914–24Google Scholar
- 18.Carrafiello G, Laganà D, Nosari AM, Guffanti C et al (2006) Utility of computed tomography (CT) and of fine needle aspiration biopsy (FNAB) in early diagnosis of fungal pulmonary infections. Study of infections from filamentous fungi in haematologically immunodeficient patients. Radiol Med 111(1):33–41CrossRefPubMedGoogle Scholar
- 30.Romanes GJ (1981) Cunningham’s textbook of anatomy. Oxford University Press, LondonGoogle Scholar
- 65.Kim GR, Hur J, Lee SM et al (2011) CT fluoroscopy-guided lung biopsy versus conventional CT-guided lung biopsy: a prospective controlled study to assess radiation doses and diagnostic performance. Eur RadiolGoogle Scholar
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