Liquid-based cytology findings of glassy cell carcinoma of the cervix. Report of a case with histologic correlation and molecular analysis

BACKGROUND: Glassy cell carcinoma is a rare form of poorly differentiated carcinoma of the cervix with no obvious squamous or glandular differentiation. Its liquid-based cytology findings have not been described before. CASE: A 46-year-old Filipina presented with vaginal bleeding due to a bulky cervical tumor. The liquid-based cytology preparation was of moderate cellularity and contained small clusters of polygonal to elongated tumor cells admixed with amphophilic, granular, necrotic debris. The malignant cells possessed round to oval nuclei; a thin nuclear membrane; finely dispersed chromatin; prominent, solitary nucleoli; abundant, cyanophilic cytoplasm; and discrete cell borders. Occasional tumor cells showed phagocytosis of polymorphs. The background contained a mixed population of inflammatory cells. Eosinophils, though present, were not readily identified in the cytologic specimen. There was no evidence of dyskeratosis, cytoplasmic vacuolation or koilocytosis. Histologic and ultrastructural examination of the tumor biopsy showed classic features of glassy cell carcinoma. Molecular analysis using polymerase chain reaction and restriction fragment length polymorphism revealed the presence of human papillomavirus (HPV) DNA in the liquid-based cytology sample. The HPV genotype, however, did not belong to any of the commonly encountered prototypes. CONCLUSION: Glassy cell carcinoma of the cervix may show distinct, though subtle, cytomorphologic features in liquid-based preparations. The findings, however, are slightly different from those in conventional cervical smears. Awareness of this rare entity is important, as glassy cell carcinoma is often associated with more aggressive clinical behavior.