P53 immunohistochemistry has been used to distinguish between malignant tumors and morphologically similar benign processes. In the central nervous system, a major diagnostic dilemma is caused by overlapping features of benign reactive astrocytic lesions and low-grade astrocytomas, especially with small biopsies. P53 immunoreactivity in astrocytes could be useful in differentiating benign reactive lesions from malignant astrocytomas. An immunohistochemical study on 110 brain lesions from 108 patients using a monoclonal antibody (DO-7) against p53 protein was conducted. Using the modified Ringertz and World Health Organization system, the specimens included 22 astrocytomas, 12 anaplastic astrocytomas, 42 glioblastoma multiforme tumors, three nonglial tumors, and 56 reactive astrocytic lesions to 25 neoplasms, nine infectious processes, six cerebrovascular disorders,one metabolic disorder, two vascular malformations, eleven degenerative/demyelinating lesions, and two unknown primary lesions. Immunoreactive astrocytic tumors included 12 (54%) astrocytomas, nine (75%) anaplastic astrocytomas, and 38 glioblastoma multiforme tumors (90%). Among the reactive astrocytic lesions, only five (9%) cases of progressive multifocal leukoencephalopathy were immunoreactive. These data demonstrate that p53 immunoreactivity in astrogliosis is unusual but is to be expected in astrocytomas and can help to differentiate reactive from neoplastic astrocytic lesions.

No abstract

Ninety-five percent (195) of 203 fine needle aspiration biopsies (FNAB) of head and neck specimens contained adequate tissues for histologic evaluation. No complications or needle tract recurrences were identified. Out of 135 patients whose surgical excision followed FNAB, 5% (7/135) of the biopsies were nondiagnostic. Correlation of cytologic and histologic findings of the remaining 128 FNAB revealed a sensitivity rate of 82% (46/56), a specificity rate of 99% (71/72), and a positive predictive of value of 98% (46/47). The diagnostic accuracy of FNAB was better with salivary gland and cervical node specimens than with thyroid, skin, and subcutaneous specimens. Fine needle aspiration biopsy may be considered as the first diagnostic step in the evaluation of the mass of the head and neck region, if the nondiagnostic aspiration rate is low and the diagnostic accuracy is high.