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 Enlarged and prominent nucleoli may be indicative of MYCN amplification: a study of neuroblastoma (Schwannian stroma-poor), undifferentiated/poorly differentiated subtype with high mitosis-karyorrhexis index. Kobayashi C, Monforte-Munoz HL, Gerbing RB, Stram DO, Matthay KK, Lukens JN, Seeger RC, Shimada H. Cancer. 2005 Jan 1;103(1):174-80. PMID: 15549714

 Morphologic features of neuroblastoma (Schwannian stroma-poor tumors) in clinically favorable and unfavorable groups. Ambros IM, Hata J, Joshi VV, Roald B, Dehner LP, Tüchler H, Pötschger U, Shimada H. Cancer. 2002 Mar 1;94(5):1574-83. PMID: 11920516