Carotid body paragangliomas and matrix metalloproteinases

The carotid body tumors (CBTs) are relatively rare neoplasms and may present into benign or life threatening malignant forms. Matrix metalloproteinases (MMPs) are often involved in vascular and cancer diseases. Objective of this study is to study the relationship between CBTs and MMPs.

We performed a multicenter study on 14 patients with CBTs. All tumors were resected. For each patient, we evaluated the MMPs' levels in both plasma (enzyme-linked immunosorbent assay [ELISA] test) and tissue samples (Western blot analysis). These MMPs' plasma levels were compared with the MMPs' plasma levels of healthy patients.

Eleven patients had benign CBTs, whereas 3 patients had malignant CBTs. ELISA findings revealed significant higher levels (P < 0.01) of MMP-1, -2, -3, -8, and -9 in patients with paraganglioma with respect to healthy patients. Patients with malignant CBTs showed significantly higher levels (P < 0.01) of MMP-1, -2, and -3 compared with patients with benign CBTs.

Because this is an exploratory study, the experience on this casuistry showed that MMPs' evaluation may help clinicians and surgeons to formulate a more rapid and clear diagnosis on CBTs' behavior. However, other studies on a large group of patients may be useful to validate these observations.