The value of a noninvasive diagnostic approach to mediastinal masses

Mediastinal tumors show a wide variability, and therefore, a standardized diagnostic and therapeutic workup is instrumental. We subdivided mediastinal tumors into nonlymphatic mediastinal tumors (NLMTs), most of which require surgical resection without need of preoperative histology, and mediastinal lymphadenopathy (MLA), requiring surgical biopsy for exact histologic classification. We investigated the accuracy of noninvasive diagnostic studies distinguishing between the two groups of MLA and NLMT.

A retrospective analysis was performed on patients who had previously undergone surgery on mediastinal tumors. Their data were statistically analyzed (chi2 test, logistic regression analysis), and the values of medical history, physical examination, laboratory tests, and computerized tomography scan discriminating between MLA and NLMT were assessed.

Out of 299 patients included in the study, 242 (80.9%) had MLA and 57 (19.1%) had NLMT. Sensitivity and specificity of noninvasive investigations for differentiation of MLA and NLMT were 98.2% and 86.0%, respectively. Whereas the prevalence of thoracic symptoms such as shortness of breath, cough, or chest pain was similar in both groups (MLA, 165 [69.3%]; NLMT, 41 [69.5%]; p = 0.98), systemic symptoms, including fever, night sweats, or weight loss (MLA, 110 [49.8%]; NLMT, 17 [29.3%]; p < 0.01), and signs of inflammation, such as c-reactive protein, erythrocyte sedimentation rate, and leukocytosis (MLA, 202 [85.6%]; NLMT, 34 [57.6%]; p < 0.001), were significantly more common in MLA.

Noninvasive diagnostic procedures, including medical history, physical examination, laboratory tests, and computerized tomographic scan, are highly sensitive in detecting MLAs that should undergo surgical biopsy. Our data suggest confirming all suspected NLMTs by fine needle aspiration (FNA) biopsy before surgery.