Immunohistochemical staining of cytologic smears with MIB-1 helps distinguish low-grade from high-grade neuroendocrine neoplasms.
Neuroendocrine neoplasms (NENs) of the lung and gastrointestinal tract constitute a pathologic and biologic spectrum of tumors. Accurate cytologic diagnosis of a neuroendocrine neoplasm is important since definitive treatment frequently is based on low- and high-grade categories without histologic sampling. In many instances, however, low- and high-grade NENs share cytologic features, hindering a precise classification. Since the histologic diagnostic criteria for separation of low- from high-grade categories can be based on the proliferation rate, we proposed to evaluate the usefulness of the immunocytochemical stain for the proliferation marker MIB-1 in the grading of NENs. Cytologic preparations of 63 NENs were retrieved from the files of Memorial Sloan-Kettering Cancer Center, New York, NY. One representative alcohol-fixed slide from each case was destained and restained immunocytochemically for MIB-1. When MIB-1 immunoreactivity was considered, all low-grade NENs showed immunoreactivity in fewer than 25% of the neoplastic cells, and all high-grade NENs demonstrated immunoreactivity in more than 50% of neoplastic cells. Our study demonstrates that MIB-1 dramatically stratifies NENs as low-grade or high-grade. Therefore, the proliferation index also correlates with grade of NEN in cytology specimens.
Lin
Oscar
O
Department of Pathology, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY 10021, USA.
Olgac
Semra
S
Green
Ileana
I
Zakowski
Maureen F
MF
Klimstra
David S
DS
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D018278:Carcinoma, Neuroendocrine / Q000145:classification / Q000378:metabolism* / Q000556:secondary; D003581:Cytodiagnosis / Q000379:methods*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen