Applications of the microbiopsy technique in non-cervical cytology: where cytology and histology meet

Aim: To evaluate a recently developed technique allowing the removal and processing for histology of thick tissue fragments, called microbiopsies, from noncervical cytology specimens. Methods and results: Forty-five non-cervical smears from malignant tumours which contained microbiopsies were selected and processed. Sufficient sections could be cut in most cases for haematoxylin and eosin and an extensive panel of immunostaining. Seventy-one per cent of histological slides from the microbiopsies were representative of the tumour and confirmed the diagnosis. In 29% of the cases they were too small, contained non-representative tissue or showed extensive necrosis. Surprisingly, immunostaining results were at least the same and often better than those observed in routine formalin-fixed, paraffin-embedded tissue. Immunostaining profiles allowed distinction of tumour subtypes. Antigen retrieval techniques could be avoided in all cases. Conclusions: Application of the microbiopsy technique in routine cytology smears containing microbiopsies is helpful, particularly in those cases in which the diagnosis is not clear on the basis of the cytology smear and in cases in which there are not enough cytology slides for immunohistochemical examination.