Automated Cellient(™) cytoblocks: better, stronger, faster?

Area of Science:

• Cytopathology
• Histopathology
• Biotechnology

Background:

• Cell blocks (CBs) enhance morphological detail and enable immunocytochemistry (ICC) in cytopathology.
• The Cellient system offers rapid CB preparation (45 minutes) using methanol fixation, contrasting with traditional methods requiring overnight formalin fixation.

Purpose of the Study:

• Compare Cellient and traditional CB methods for cellularity, morphology, and immunoreactivity.
• Evaluate adding formalin fixation to the Cellient method for ICC.
• Determine optimal sectioning depth for Cellient CBs to maximize cellularity.

Main Methods:

• 160 CBs from 40 cytology samples (32 malignant, 8 benign) were processed using four methods: traditional, Cellient (methanol), Cellient + 30 min formalin, Cellient + 60 min formalin.
• Morphology and cellularity were assessed via H&E staining by blinded reviewers.
• ICC was performed on 14 cases using a panel of antibodies.
• Serial sectioning determined optimal thickness for Cellient CBs.

Main Results:

• Cellient CBs demonstrated superior morphology for malignant cases compared to traditional CBs (P < 0.001).
• Cellularity was comparable across all processing methods.
• ICC staining quality was excellent in all groups; adding formalin did not impact staining.
• Optimal cellularity in Cellient CBs was achieved at 30-40 μm, yielding at least 27 sections.

Conclusions:

• Cellient CBs provide superior morphology over traditional methods.
• Formalin fixation can be incorporated into the Cellient process for ICC without compromising results.
• Optimal sectioning depth of 30-40 μm for Cellient CBs impacts daily case handling.