Unexpected uptake of technetium 99m hexakis-2-methoxy-isobutylisonitrile in giant lymph node hyperplasia of the mediastinum (Castleman's disease).

The case of a patient with giant lymph node hyperplasia of the mediastinum who unexpectedly showed focal uptake of technetium 99m hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) is presented in this article. The patient was included in our research programme of tumor imaging with 99mTc-MIBI because the appearance of the mass on the chest radiogram and CT scan resembled a mediastinal tumour. Final diagnosis of giant lymph node hyperplasia was achieved through histopathological examination of the surgically removed lymph node.