Isolated mediastinal adenopathy: the case for mediastinoscopy

We report our experience with mediastinoscopy at Auckland city hospital, a tertiary referral centre. We wished to examine correlations between clinical diagnosis and that made by histological sampling of enlarged mediastinal nodes particularly in patients with isolated mediastinal adenopathy.

We retrospectively reviewed clinical records of all patients who underwent mediastinoscopy in a five year period, mediastinoscopy was performed in the presence of enlarged lymph nodes (short axis > 1cm) found at CT. Mediastinoscopy was indicated for diagnostic staging of mediastinal adenopathy related to a parenchymal lung mass, diagnosis of isolated mediastinal adenopathy and diagnosis of mediastinal adenopathy with other CT findings. Data relating to indication, pre-test diagnosis, node stations sampled, histology, and operative complications were collected.

Mediastinoscopy was performed in 137 consecutive patients. Seventy five patients had a lung mass, 47 had isolated mediastinal adenopathy and 15 had other CT findings. One operative complication occurred. In those patients with isolated adenopathy the following diagnoses were reached; sarcoidosis 23, TB 15, lymphoma 4, carcinoma 4, no diagnosis 1. Final diagnosis was significantly associated with patient's ethnicity. There was high sensitivity and specificity on comparison of clinical and histological diagnosis for both TB and sarcoidosis cases.

Mediastinoscopy proved to be safe and effective in nodal assessment of the mediastinum. In carefully selected cases procedural morbidity and mortality may be avoided by application of features related to patient's ethnicity and radiological findings.