ABSTRACT
Meningiomas are the most common benign intracranial neoplasms. Nearly 20% of all primary intracranial tumors are meningiomas. Primary intraosseous meningiomas are a subtype of the meningiomas that represents the most uncommon manifestation of meningiomas. Although rare, these tumors can be found to occur in unexpected areas of the head and neck. The patient was a 78- year-old male who was operated two times for urinary bladder cancer. During his routine oncology follow-ups, the PET scan demonstrated a hyperactive area in the right parietal bone. Preoperative diagnosis was a metastasis, but histological examination revealed an osteolytic interosseous meningioma. The possibility of an intraosseous meningioma mimicking a metastatic tumor should be kept in mind.
Subject(s)
Meningioma/diagnostic imaging , Neoplasms, Second Primary/diagnostic imaging , Parietal Bone/diagnostic imaging , Skull Neoplasms/diagnostic imaging , Aged , Diagnosis, Differential , Humans , Male , Meningioma/secondary , Neoplasms, Second Primary/pathology , Parietal Bone/pathology , Positron-Emission Tomography , Radiography , Skull Neoplasms/secondary , Urinary Bladder Neoplasms/pathologyABSTRACT
UNLABELLED: 99mTc-d,1-hexamethylpropyleneamine oxime (HMPAO) is widely used as a labeling agent for leukocytes in the diagnosis of inflammatory or infectious foci. Cytotoxicity studies have indicated that intracellular labeling of leukocytes with (111)In compounds may have severe detrimental effects on the cells. METHODS: In this study, the radiotoxic effects on mixed lymphocytes after labeling with (99m)Tc-HMPAO was investigated using the cytokinesis-blocked micronucleus assay and chromosomal aberration assay. RESULTS: Whereas negligible numbers of chromosome abnormalities were noted in unlabeled lymphocytes, the labeled lymphocytes showed multiple aberrations of various types, including dicentric, tricentric, and fivecentric chromosomes; centric rings; chromosome and chromatid type breaks; and acentric fragments. CONCLUSION: Heavily aberrant lymphocytes are seen in (99m)Tc-HMPAO-labeled mixed leukocytes after routine clinical procedures. It is unlikely, however, that this would cause detrimental effects, such as lymphoid malignancy, as these cells would normally be eliminated through apoptosis or phagocytosis.
