| Popis: |
The major limitation of cytological preparations from fine needle aspiration (FNA), i.e. poor preservation of tissue architecture, could be circumventd by the use of cell blocks (CB). The 21-gauge needle yielded more and larger tissue of fragments suitable for histology with no increased risk of complications. The tissue was fixed directly in 7.5% buffered formalin and processed through shortened xylene cycle for better morphology. In thyroid lesions, CB allowed recognition of hyperplastic papillae and fragments of dilated follicles which were characteristic of colloid nodules and enabled distinction from follicular neoplasms to be made. On the other hand, follicles lined by columnar cells and prominent sinusoid stroma are in favour of follicular neoplasms. In the liver, CB revealed the trabecular and sinusoidal pattern of hepatocellular carcinoma well. Immnocytochemistry was also much more conveniently performed on CB which provided more sections to work on. The short and yet better fixation also enabled superior preservation of antigens. A histologial approach, in addition to cytological, would enhance diagnostic yield of FNA. |
