Abstract

OBJECTIVE:

This study aimed to evaluate the diagnostic value of radioimmunoimaging by radionuclide-labeled monoclonal antibody F023C5 (MAb), raised originally against carcinoembryonic antigen (CEA), in patients with glomus tympanicum tumors.

STUDY DESIGN:

Prospective.

SETTING:

Preoperative imaging versus radioactivity of removed tumor.

PATIENTS:

Two patients with paraganglioma (glomus tympanicum).

INTERVENTION:

Diagnostic.

MAIN OUTCOME MEASURE:

Radiolabeled MAb accumulates in paraganglioma tissue. Single photon emission computed tomography (SPECT) provides improved detection of lesions.

RESULTS:

SPECT using F023C5 MAb detected the abnormal accumulation of radioactivity in the middle ear region. This method detected paraganglioma less than 1 cm in diameter.

CONCLUSIONS:

Successful detection of glomus tympanicum in two patients using In-111-labeled F023C5 MAb is reported. The result suggests the radioimmunoimaging using this antibody is useful for the detection of not only primary glomus tumors, but also of local recurrence and unsuspected lesion in patients with paragangliomas.