Mediastinoscopy in the investigation of primary mediastinal lymphadenopathy

Thymic carcinoma diagnosed by using endoscopic ultrasound with fine-needle aspiration

There is a paucity of literature on the use of endoscopic ultrasound (EUS) for evaluating superior mediastinal structures, especially the thymus gland. We report a case of thymic carcinoma diagnosed by using EUS elastography with strain ratio and fine-needle aspiration (FNA). A 64-year-old woman presented with altered mental status and was diagnosed with autoimmune encephalitis. Further work-up suggested a superior mediastinal mass, for which she underwent EUS. A hypoechoic mass was found in the superior mediastinum at the level of the aortic arch. Real-time EUS elastography showed a predominantly blue hue to the mass concerning for malignancy. FNA of the mass was performed, which revealed numerous large neoplastic cells under a background of a small lymphoid infiltrate. Immunohistochemistry was strongly positive for PAX8, pancytokeratin, and CAM5.2. The pathologic and immunohistochemical stains were consistent with thymic carcinoma.

Subcarinal collection following mediastinoscopy: a normal post-procedural CT finding

AIM

To determine the frequency with which a subcarinal collection is present at computed tomography (CT) following mediastinoscopy and to determine the CT features of the collection.

MATERIALS AND METHODS

All patients who underwent uncomplicated mediastinoscopy during a 1-year period were retrospectively identified. This list was cross-referenced to determine those patients who also underwent CT within 15 days after the procedure. Each post-mediastinoscopy CT examination was assessed in consensus by three fellowship-trained thoracic radiologists for the presence of subcarinal abnormalities, which were also characterized in terms of their size and density. Additional CT findings were recorded, including tracheobronchial wall thickening, paratracheal collections, mediastinal fat stranding, and mediastinal air.

RESULTS

The study cohort included 10 patients (seven men and three women) with mean age of 65 years (range 49-81 years). CT was performed a mean of 11 days following mediastinoscopy. The most common CT finding was an oval subcarinal collection in nine of 10 cases (size 1.1-3.2 cm). In all nine cases, the subcarinal collections were consistently lower in attenuation than the subcarinal lymph node in the same region on the pre-procedure CT examination. Other CT findings included anterior tracheobronchial wall thickening (n=7); paratracheal collection (n=6); mediastinal fat stranding (n=6); and mediastinal air in (n=4) cases.

CONCLUSION

A subcarinal collection was identified in 90% of cases following mediastinoscopy. Its rapid development and characteristic appearance help to distinguish it from a lymph node.

Mediastinal transthoracic needle and core lymph node biopsy: should it replace mediastinoscopy?

STUDY OBJECTIVES

Primary assessment of mediastinal lymph nodes (N2 or N3) for staging lung cancer by transthoracic needle with or without core biopsy. Mediastinoscopy only performed after FNA failed to yield a diagnosis.

DESIGN AND SETTINGS

A retrospective study in a university setting.

PATIENTS

Eighty-nine patients with mediastinal lymphadenopathy (> 1.5 cm in short-axis diameter) by CT.

METHODS

Mediastinal transthoracic fine-needle aspiration (FNA) with or without core biopsy was performed prior to mediastinoscopy in 89 patients with mediastinal lymphadenopathy (lymph node > 1.5 cm in short-axis diameter) or masses by CT.

RESULTS

Mediastinal transthoracic FNA was used alone in 39 of 89 patients, or with core biopsy in 50 of 89 patients. Mediastinal transthoracic FNA with or without core biopsy was diagnostic in 69 of 89 patients (77.5%) for cancer cell type, sarcoidosis, or caseating granulomas with or without tuberculosis. Transthoracic FNA with or without core biopsy of nodal stations (total, 94 biopsies) judged readily accessible by mediastinoscopy (n = 59) included paratracheal (n = 56) and highest mediastinal (n = 3); those more difficult (n = 26) included subcarinal (n = 20) and aorticopulmonary window (n = 6); and those impossible (n = 9) included paraesophageal and pulmonary ligament (n = 6), parasternal (n = 2), and para-aortic (n = 1). Innovative lung protective techniques for CT-guided biopsy access windows included "iatrogenic-controlled pneumothorax" (n = 10) or saline solution injection creating a "salinoma" (n = 11). Pneumothorax was detected in only 10% with a "protective" technique but 60% when traversing lung parenchyma. Transthoracic FNA with or without core biopsy failed to yield a diagnosis in 20 of 89 patients (22.5%); all then underwent mediastinoscopy, with 11 of 20 procedures (55%) diagnostic for cancer, and 9 of 20 procedures diagnostic of benign diagnosis or no cancer.

CONCLUSION

Transthoracic FNA with or without core biopsy accesses virtually all mediastinal nodal stations is diagnostic in 78% of cases with mediastinal adenopathy or masses, and should precede mediastinoscopy in the staging of lung cancer or workup of mediastinal masses.

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.

Image-Guided Fine Needle Aspiration Strategies for Staging of Lung Cancer

Image-guided transthoracic, bronchoscopic, and endoscopic ultrasound fine needle aspiration (FNA) greatly facilitates lung cancer staging by having the potential to precisely biopsy lung lesions and virtually all mediastinal lymph node stations. Imaging modalities alone, including chest x-ray, computed tomography (CT), magnetic resonance imaging, and positron emission tomography identify lesions suspicious for cancer but cannot make a tissue diagnosis. We describe an algorithm for the diagnosis and tumor-node-metastasis staging of lung cancer that uses procedures with the least invasiveness and cost with the highest diagnostic yields. For the anterior mediastinum, fluoroscopic-, ultrasound-, or CT-guided transthoracic FNA (which has a greater yield than bronchoscopy and is less invasive than mediastinoscopy) should be the primary technique for lymph node sampling. In the middle mediastinum, CT-guided transthoracic FNA is preferred for all nodal stations except subcarinal. Endoscopic ultrasound-guided FNA (EUS-FNA), which enables real-time biopsies within 5 cm of the esophagus, is preferred for sampling subcarinal and posterior mediastinal nodes because the yield is similar to CT-guided transthoracic FNA, with minimal risk of pneumothorax. The posterior mediastinum is also accessed by fluoroscopic- or CT-guided transthoracic FNA or video-assisted thoracic surgery. Sampling of the aorticopulmonary window depends on lymph node size; if the nodes are large enough to displace the aortic arch and pulmonary vein, then EUS-FNA is attempted, and if the nodes are not sufficiently enlarged, CT-guided transthoracic FNA should be performed prior to thoracoscopy or thoracotomy.

Surgical endoscopic techniques in the diagnosis and follow-up of patients with lymphoma

BACKGROUND

In patients with lymphoma, tissue for histology can be obtained through image-guided techniques or by surgery. The aim of this study was to assess the efficacy of surgical endoscopic techniques in obtaining adequate tissue specimens.

METHODS

Ninety-two patients with suspected or confirmed lymphoma were referred for a surgical biopsy of a deeply located intrathoracic or intra-abdominal mass or lymph node. The 86 patients who had surgery using a surgical endoscopic technique were included in this study. There were 54 men and 32 women, of mean age 34 (range 15-78) years. Most were selected directly for surgery while five previously had a failed computed tomography-guided biopsy. A total of 89 procedures were performed in 86 patients: laparoscopy (15 patients), thoracoscopy (61) and mediastinoscopy (13).

RESULTS

No patient died. One intraoperative complication occurred during thoracoscopy (1 per cent). Two postoperative complications were noted (2 per cent). Three patients required conversion to open surgery (3 per cent). Adequate tissue for histology was obtained by surgical endoscopic procedures in 87 per cent. Twelve of 13 mediastinoscopies were successful. After thoracoscopy, the success rate was 92 per cent but only nine of 15 laparoscopies were considered successful.

CONCLUSION

In patients with lymphoma, surgical endoscopic techniques have a high diagnostic yield and a low morbidity rate. Barring exceptional circumstances these should be favoured rather than conventional open surgery.

Mediastinoscopy vs thoracoscopy for mediastinal biopsy. Results of a prospective nonrandomized study

OBJECTIVE

To assess the results and the morbidity of thoracoscopy compared with conventional mediastinoscopy for the approach of mediastinal solid masses and lymph nodes, we have performed a prospective study about the respective yields, complication rates, and the length of hospital stay for patients.

MATERIAL AND METHODS

We have included 114 patients in the study. The criteria of inclusion were the accessibility of the lymph nodes and/or mass to cervical mediastinoscopy through CT scan view. There were 2 groups: 52 patients underwent a mediastinoscopy (group M) and 62 underwent a thoracoscopy (group T).

RESULTS

There were 3 failures in group M (5.7%) and 5 failures in group T (8.1%) (not significant; NS). In group M, the three procedures were converted to anterior mediastinotomy (two cases) and to thoracoscopy (one case). In group T, the five procedures were converted to anterior mediastinotomy (two cases), mediastinoscopy (two cases), and thoracotomy (one case). The diagnostic yield was 94.3% in group M and 91.9% in group T (NS). After conversion, a diagnosis was reached in all patients in group M (100%) and in all but 1 patient in group T (98.3%) (NS). There was no intraoperative complication in group M, while 2 complications occurred in group T (3.2%) (p < 0.05). The overall morbidity was zero in group M and 4.8% in group T (p < 0.05).

CONCLUSION

The diagnostic yield of mediastinoscopy is comparable to thoracoscopy. Complication rate and hospital stay of patients undergoing mediastinoscopy are significantly inferior. Thoracoscopy should be indicated only for lesions that are not within the reach of the mediastinoscope or when multiple biopsy specimens are necessary.