Middle mediastinum lesions: preliminary experience with CT-guided fine-needle aspiration biopsy with a suprasternal approach

Clinical Value of CT-Guided Fine Needle Aspiration and Tissue-Core Biopsy of Thoracic Masses in the Dog and Cat

Simple Summary

Diagnostic imaging is of paramount importance in the diagnosis of thoracic lesions. Radiology has traditionally been considered the diagnostic procedure of choice for these diseases in addition to a correct cytological and histopathologic diagnosis. In human medicine, Computed Tomography (CT) and CT-guided biopsy are used in the presence of lesions which are not adequately diagnosed with other procedures. In the present study, thoracic lesions from 52 dogs and 10 cats of different sex, breed and size underwent both CT-guided fine-needle aspiration (FNAB) and tissue-core biopsy (TCB). In this study, 59 of 62 histopathological samples were diagnostic (95.2%). Cytology was diagnostic in 43 of 62 samples (69.4%). General accuracy for FNAB and TCB were 67.7% and 95.2%, respectively. Combining the two techniques, the overall mean accuracy for diagnosis was 98.4%. CT-guided FNAB cytology can be considered a useful and reliable technique, especially for small lesions or lesions located close to vital organs and therefore dangerous to biopsy in any other way.

Abstract

Diagnosis of thoracic lesions on the basis of history and physical examination is often challenging. Diagnostic imaging is therefore of paramount importance in this field. Radiology has traditionally been considered the diagnostic procedure of choice for these diseases. Nevertheless, it is often not possible to differentiate inflammatory/infectious lesions from neoplastic diseases. A correct cytological and histopathologic diagnosis is therefore needed for an accurate diagnosis and subsequent prognostic and therapeutic approach. In human medicine, Computed Tomography (CT) and CT-guided biopsy are used in the presence of lesions which are not adequately diagnosed with other procedures. In the present study, thoracic lesions from 52 dogs and 10 cats of different sex, breed and size underwent both CT-guided fine-needle aspiration (FNAB) and tissue-core biopsy (TCB). Clinical examination, hematobiochemical analysis and chest radiography were performed on all animals. In this study, 59 of 62 histopathological samples were diagnostic (95.2%). Cytology was diagnostic in 43 of 62 samples (69.4%). General sensitivity, accuracy and PPV for FNAB and TCB were 67.7%, 67.7% and 100% and 96.7%, 95.2% and 98.3%, respectively. Combining the two techniques, the overall mean accuracy for diagnosis was 98.4%. Nineteen of 62 cases showed complications (30.6%). Mild pneumothorax was seen in 16 cases, whereas mild hemorrhage occurred in three cases. No major complications were encountered. CT-guided FNAB cytology can be considered a useful and reliable technique, especially for small lesions or lesions located close to vital organs and therefore dangerous to biopsy in other way.

Image-Guided Biopsies and Interventions of Mediastinal Lesions

Optimal assessment of the mediastinal masses is performed by a combination of clinical, radiological and often histological assessments. Image-guided transthoracic biopsy of mediastinal lesions is a minimally invasive and reliable procedure to obtain tissue samples, establish a diagnosis and provide a treatment plan. Biopsy can be performed under Computed Tomography, MRI, or ultrasound guidance, using a fine needle aspiration or a core-needle. In this paper, we review the image-guided strategies and techniques for histologic sampling of mediastinal lesions, along with the related clinical scenarios and possible procedural complications. In addition, image-guided mediastinal drainage and mediastinal ablations will be briefly discussed.

Percutaneous transthoracic needle biopsy: special considerations and techniques used in lung transplant recipients

Lung transplant recipients are among the patients most likely eventually to undergo diagnostic lung biopsy. Unfortunately, these patients are at particularly high risk for experiencing intra- and periprocedural complications. Percutaneous transthoracic needle biopsy (TNB) has over time emerged as an increasingly safe and reliable method of obtaining lung tissue for diagnosis. This article gives an overview of TNB including its indications, the imaging modalities currently used for guidance, and the special techniques utilized in performing the procedure and minimizing complications with an emphasis placed upon the special case of TNB performed in lung transplant recipients.

Computed tomography-guided fine-needle aspirate and tissue-core biopsy of intrathoracic lesions in thirty dogs and cats

Medical records and computed tomography (CT) images were reviewed retrospectively for 30 animals (27 dogs, two cats, one cougar) in which CT-guided intrathoracic fine-needle aspirates (FNA) (12), core biopsies (10) or both (8) were performed. Sample interpretation was listed as diagnostic or nondiagnostic and nonneoplasia or neoplasia. Diagnostic results were inconclusive in 35% FNA and 17% biopsies. FNA and biopsy interpretations were in agreement in seven patients, one nonneoplasia, and six neoplasia. A clinical diagnosis was made in 65% FNA and 83% biopsies. When 18 patients with confirmed diagnoses were used, overall accuracy for diagnosis was 92% for FNA and biopsy and the sensitivity for neoplasia was 91% using fine needle aspirate and 80% using biopsy. Complications seen on CT images were noted in 43% of patients, four pneumothorax, five pulmonary hemorrhage, and four with both. No clinical manifestations were noted and treatment was not necessary. Significant correlation was noted between complications and penetration of aerated lung, but not with lesion location, type of disease, method of sampling, width of mass and depth of aerated lung penetrated. CT-guided sampling is relatively safe and useful in the diagnosis of intra-thoracic lesions, especially neoplasia. FNA samples are nondiagnostic more often than biopsy samples. Sub-clinical pneumothorax and hemorrhage are common when aerated lung is penetrated.

Protective Pneumothorax for Needle Biopsy of Mediastinum and Pulmonary Hilum

The risk of performing CT-guided transthoracic needle biopsy of some mediastinal and pulmonary hilar masses is increased by the presence of intervening lung. A series of patients is presented in whom a protective pneumothorax provided access for biopsy of masses in the mediastinum and pulmonary hilum. Review of Interventional Radiology records revealed 24 patients who had biopsies of mediastinum or pulmonary hilum, in whom protective pneumothorax was used, or attempted, to provide percutaneous access for biopsy. Characteristics of these patients and their procedures were reviewed. Percutaneous access to the pleural space was gained in 21/24 (88%) of patients. A protective pneumothorax was established in 19 (79%); 2 patients had pleural adhesions that prevented the lung from being displaced. The process of creating the protective pneumothorax added a mean time of 17 minutes to the procedure (range 6-30 minutes). All patients had biopsy using coaxial technique, with either a 20-gauge or 18-gauge core biopsy instrument, in addition to needle aspiration. Air leak requiring tube drainage occurred in 1/19 (5%) of patients who had a protective pneumothorax, and in 2/5 (40%) of patients in whom protective pneumothorax was not established. Percutaneous creation of a protective pneumothorax is a safe method that provides access for needle biopsy of deep lesions in the chest without traversing aerated lung.

Imaging-guided Percutaneous Biopsy of Mediastinal Lesions: Different Approaches and Anatomic Considerations

Percutaneous needle biopsy with imaging guidance allows access to lesions in virtually all mediastinal locations. A direct mediastinal approach, which enables extrapleural needle placement, is the preferred method to avoid the risk of pneumothorax. Techniques that allow extrapleural access include the parasternal, paravertebral, transsternal, and suprasternal approaches, which are performed with computed tomographic or ultrasonographic guidance. The parasternal approach is used for biopsy of anterior or middle mediastinal lesions when the lesion or intervening mediastinal fat extends to the anterior chest wall, lateral to the sternum; injury to the internal mammary vessels is a potential complication. The paravertebral approach is used for biopsy of subcarinal and other posterior mediastinal lesions; saline solution is often injected to widen the mediastinum. The transsternal approach, which involves needle placement through the sternum, is used for biopsy of anterior or middle mediastinal lesions that are not accessible with the parasternal approach. Biopsy of superior mediastinal lesions can be performed with a suprasternal approach. An alternative to these direct mediastinal approaches involves advancing the needle through a pleural space created by an existing pleural effusion or iatrogenic pneumothorax. Another alternative is the transpulmonary approach, which involves transgression of the lung and visceral pleura by the needle and is associated with a substantial risk of pneumothorax.

CT-Guided Radiofrequency Ablation:A Potential Complementary Therapy for Patients with Unresectable Primary Lung Cancer—A Preliminary Report of 33 Patients

OBJECTIVE

We report our preliminary evaluation of the effectiveness, safety, technical feasibility, and complications of palliative CT-guided radiofrequency ablation of unresectable primary pulmonary malignancies.

SUBJECTS AND METHODS

Thirty-three patients (26 men and seven women; age range, 44-75 years; mean age, 66 years) with unresectable malignant lung neoplasms underwent 35 CT-guided tumor ablation sessions. Follow-up CT was performed 6 months (29 cases) and 1 year (10 cases) after treatment. In 19 patients, these findings were correlated with cytohistopathologic assessment obtained with CT-guided fine-needle aspiration biopsy or core biopsy at 6-month follow-up. Size and CT appearance of the treated lesions were correlated with cytohistologic features and clinical scores.

RESULTS

Thirty-five technically successful radiofrequency ablation treatments were performed. The only complications in the periprocedural period were three cases of minor pneumothorax, five cases of sputum cruentum, and three asymptomatic pleural effusions. Contrast-enhanced CT performed at 6-month follow-up showed four cases of complete and 13 cases of partial lesion ablation, 11 cases of stabilized lesion size, and one case of increased lesion size. Contrast-enhanced CT performed at 1-year follow-up showed unchanged lesion size in six cases and reduction in four cases. Six-month cytohistologic examinations showed total coagulation necrosis in seven lesions and partial necrosis in 12. Clinical improvement in pretreatment symptoms was observed in 12 of 29 patients seen at 6-month follow-up. Eight patients died within 1 year of treatment of non-procedure-related causes.

CONCLUSION

Our experience suggests that radiofrequency ablation can be used successfully in unresectable lung cancer as an alternative or complementary treatment to radio- or chemotherapy. Larger studies are necessary to fully evaluate its potential combination with other treatment techniques.

Lung cancer staging

The staging of lung cancer is a continuously progressing field, with advances in technology not only improving prognostic accuracy, but fundamentally changing pre-operative investigation algorithms. Noninvasive staging is currently undergoing revolutionary developments with the advent of Positron Emission Tomography, whereas Video-Assisted Thoracic Surgery has already been established as an essential, minimally invasive diagnostic tool for invasive histological staging. Molecular staging may transform future lung cancer staging, promising extremely accurate substaging, and potentially prompting a revision of our anatomically based conceptualization of lung cancer spread. This review presents an appraisal of current lung cancer staging modalities, and presents an overview of recent developments in molecular staging.

Non-small cell lung cancer staging techniques and endoscopic ultrasound: tissue is still the issue

Non-small cell lung cancer (NSCLC) in the United States will continue to be a major public health issue, particularly as our elderly population grows. As surgery offers the best hope of cure for NSCLC, staging of NSCLC is critical because it directly impacts on the management of lung cancer. Cost, quality of life, safety, and accuracy of various staging methods all influence the clinical outcome. Staging of NSCLC is evolving due to the emergence of new and improved technologies. The objective of this article is to review the current methods used in staging of NSCLC. Currently, positron emission tomography and endoscopic ultrasound (EUS) show promise in identifying patients that may benefit from surgery. Histologic confirmation via EUS-guided fine-needle aspiration, however, may still be necessary to accurately stage the mediastinum.

Computed tomography-guided biopsy of mediastinal lesions: fine versus cutting needles

PURPOSE

To report the experience of a radiology department in the use of computed tomography guided biopsies of mediastinal lesions with fine and cutting needles, describing the differences between them. The results of adequacy of the sample and histologic diagnoses are presented according to the type of needle used.

METHODS

We present a retrospective study of mediastinal biopsies guided by computed tomography performed from January 1993 to December 1999. Eighty-six patients underwent mediastinal biopsy in this period, 37 with cutting needles, 38 with fine needles, and 11 with both types (total of 97 biopsies).

RESULTS

In most cases, it was possible to obtain an adequate sample (82.5%) and specific diagnosis (67.0%). Cutting-needle biopsy produced a higher percentage of adequate samples (89.6% versus 75.5%, P = 0.068) and of specific diagnosis (81.3% versus 53.1%, P = 0.003) than fine-needle biopsy. There were no complications that required intervention in either group.

CONCLUSION

Because they are practical, safe, and can provide accurate diagnoses, image-guided biopsies should be considered the procedure of choice in the initial exploration of patients with mediastinal masses. In our experience, cutting needles gave higher quality samples and diagnostic rates. We recommend the use of cutting needles as the preferred procedure.

Bronchoscopy and needle biopsy techniques for diagnosis and staging of lung cancer

Lung cancer is the leading cause of cancer deaths in the United States. The individual therapeutic approach and prognosis depends on accurate diagnosis and staging. Flexible bronchoscopy (FB) and transthoracic needle biopsy (TNB) are the most widely used techniques for this purpose. This article provides a critical overview of indications, diagnostic yield, and limitations of bronchoscopy and TNB in the diagnosis of lung cancer.

Cost-minimization analysis of alternative diagnostic approaches in a modeled patient with non-small cell lung cancer and subcarinal lymphadenopathy

OBJECTIVE

To evaluate the costs of alternative diagnostic evaluations of enlarged subcarinal lymph nodes (SLNs) in modeled patients with non-small cell lung cancer (NSCLC).

METHODS

A cost-minimization model was used to compare 5 diagnostic approaches in the evaluation of enlarged SLNs in modeled patients with NSCLC. Values for the test performance characteristics and prevalence of malignancy in patients with SLN were obtained from the medical literature. The target population was adult patients known or suspected to have NSCLC with SLNs with a short axis length of at least 10 mm on thoracic computed tomography (CT).

RESULTS

The lowest-cost diagnostic work-up was by initial evaluation with endoscopic ultrasonography-guided fine-needle aspiration (EUS FNA) biopsy ($11,490 per patient) compared with mediastinoscopy (with biopsy) ($13,658), transbronchial FNA biopsy ($11,963), CT-guided FNA biopsy ($13,027), and positron emission tomography ($12,887). The results were sensitive to rate of SLN metastases and EUS FNA sensitivity. The EUS FNA biopsy remained least costly if the probability of SLN metastases exceeded 24% or EUS FNA sensitivity was higher than 76%. Primary mediastinoscopy was the most economical if not.

CONCLUSIONS

Which testing strategy is least costly for SLN evaluation in a modeled patient with NSCLC may be determined by the pretest probability of nodal metastases. Use of EUS FNA biopsy minimizes the cost of diagnostic evaluation in most cases.

CT-guided percutaneous needle biopsy of intrathoracic lesions by using the transsternal approach: experience in 37 patients

PURPOSE

To report our experience with computed tomography (CT)-guided coaxial needle biopsy of intrathoracic lesions by using the transsternal approach.

MATERIALS AND METHODS

Medical records of 37 consecutive patients who underwent CT-guided transsternal biopsy of intrathoracic lesions were evaluated retrospectively. A coaxial needle technique was used in all patients; an 18-gauge needle was used for transsternal penetration, through which a 22-gauge needle was passed to obtain fine-needle aspirates. Five patients also underwent core-needle biopsy with a coaxially introduced 20-gauge needle. Medical records were reviewed for lesion size and location, needle path, number of needle penetrations, reasons for failure, biopsy results, and complications.

RESULTS

The transsternal approach was used in mediastinal (n = 32) or intrapulmonary (n = 5) lesions. Transsternal needle sampling of the target lesion was successful in 35 patients. In the remaining two, adequate angling of the transsternal needle could not be achieved. Extrapleural access to the mediastinal lesions was achieved in all but one patient in whom the 22-gauge needle traversed the lung. Major vessels were avoided in most patients; the 22-gauge needle was safely passed through the brachiocephalic vein in one patient with a retrotracheal mass. Thirty-two (91%) of the 35 biopsies yielded diagnostic specimens. No major complications were encountered. Minor complications were pneumothorax in one patient and mediastinal hematoma in another.

CONCLUSION

The CT-guided transsternal approach for coaxial core-needle biopsy allows safe access to masses in various locations in the mediastinum and anteromedial lung.

Mediastinal lymphadenopathy in patients with or without previous malignancy: EUS-FNA-based differential cytodiagnosis in 153 patients

OBJECTIVE

Mediastinal lymphadenopathy (ML) is a cause for concern, especially in patients with previous malignancy. The investigation of choice is thoracic CT with a variable sensitivity and specificity requiring tissue diagnosis. We used endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for cytodiagnosis of ML in patients with and without previous malignancy. The cause, distribution of lesions, and incidence of second cancers were investigated.

METHODS

Linear echoendoscopes and 22-gauge needles for cytology were used for EUS-FNA. A cytological diagnosis of malignancy was accepted, and histology or consistent follow-up of at least 9 months confirmed benign results.

RESULTS

One hundred fifty-three patients underwent EUS-FNA between November 1997 and November 1999 (mean age, 60 yr; range, 13-82 yr; 105 men). Cytology was adequate in 150 patients. Final diagnosis was malignancy in 84 and benign in 66 patients (sensitivity, specificity, and diagnostic accuracy: 92%, 100%, 95%, respectively). In 101 patients without previous cancer cytology identified 48 malignant (lung, 41; extrathoracic, 7) and 51 benign lesions (inflammation, 35; various, 9; sarcoidosis, 7) (sensitivity, specificity, accuracy: 88%, 100%, 94%). Fifty-two patients had prior malignancy, mostly in extrathoracic sites. Cytology revealed recurrences in 21 patients, second cancer in 9 and benign lesions in 21 patients (inflammatory, 11; sarcoidosis, 8; tuberculosis, 1; abscess, 1) (sensitivity, specificity, accuracy: 97%, 100%, 98%).

CONCLUSIONS

In patients without previous cancer malignant ML originates from the lung >80%. In those with previous malignancy recurrence of extrathoracic sites is the major cause. Benign lesions and treatable second cancers occur in a significant frequency, emphasizing the need for tissue diagnosis. EUS-FNA is a safe and minimally invasive alternative for cytodiagnosis in the mediastinum.

Transthoracic hilar and mediastinal biopsy

TNB of the mediastinum is an accurate, safe, and cost-effective diagnostic tool for the evaluation of mediastinal masses and lymphadenopathy. The technique is most useful in the staging of carcinoma, where it serves as a less expensive and minimally invasive alternative to mediastinoscopy for establishing unresectability. With recent advances in immunohistochemical and core biopsy techniques, TNB has become more accurate for establishing the initial diagnosis of lymphoma and for confirming recurrent disease. Core-needle biopsy has improved the accuracy of TNB and is particularly useful when fine-needle aspiration fails to yield a specific diagnosis, or when lymphoma or a noncarcinomatous lesion is suspected.

Transthoracic needle biopsy

Transthoracic needle biopsy (TNB) has emerged as the semi-invasive technique of choice for the diagnosis of localized intrathoracic lesions. Using CT, fluoroscopic, or sonographic guidance, TNB is highly accurate and safe when combined with expert pathologic interpretation of the aspirated specimen. This article details the preprocedural evaluation of the patient referred for TNB and discusses the technical aspects of performing the biopsy and processing and interpreting the material obtained. The reported results and complications of TNB are reviewed and followed by a brief description of the cost effectiveness of the technique and a comparison with alternative semi-invasive diagnostic techniques including bronchoscopic and video-assisted thoracoscopic biopsy.

US guidance for thoracic biopsy: a valuable alternative to CT

PURPOSE

To determine the role, accuracy, and selection criteria of ultrasonographic (US) guidance for biopsy for thoracic lesions.

MATERIALS AND METHODS

Imaging-guided thoracic biopsies (n = 86) were performed in 84 consecutive patients. US guidance was used for lesions abutting the chest wall; computed tomographic (CT) guidance was used for all masses surrounded by aerated lung. Mass location and size, guidance modality, histologic results, procedure time, and complications were recorded.

RESULTS

Thirty-four lesions (19 parenchymal, six pleural, six chest wall, three mediastinal) were amenable to US-guided biopsy. The mean mass diameter was 4.3 cm, the mean number of passes was 3.2, and the mean procedure time was 31.4 minutes. A histologic diagnosis was achieved in 31 (91%) patients, including all with small (< 2-cm) masses (n = 9). There was one case of pneumothorax. CT guidance was used in 52 (60%) of 86 cases. Lesions were parenchymal (n = 41), pleural (n = 1), and mediastinal and hilar (n = 10). The mean diameter was 2.9 cm, the mean number of passes was 2.3, and the mean procedure time was 45.2 minutes. A histologic diagnosis was achieved in 37 (71%) patients, including 18 of 27 with a small mass. Complications included pneumothorax (n = 21) and parenchymal hemorrhage (n = 2).

CONCLUSION

US is an effective and safe alternative to CT for guidance at biopsy of masses abutting the chest wall. Real-time US visualization allows accurate needle placement, shorter procedure time, and performance in debilitated and less cooperative patients.

Sonographically guided fine-needle aspiration biopsy of superior mediastinal lesions by the suprasternal route

OBJECTIVE

Our objective was to assess the technical feasibility, safety, and accuracy of sonographically guided fine-needle aspiration biopsy of superior mediastinal masses by the suprasternal route.

CONCLUSION

Sonographically guided biopsy through the suprasternal route is safe and effective for lesions in the pretracheal, right paratracheal, and prevascular compartments of the superior mediastinum. This procedure is especially useful for lesions with an acoustic window too small for parasternal biopsy under sonographic guidance.