Impact of the Pathfinder in a cytology laboratory

To assess the value of Pathfinder (CompuCyte, Cambridge, Massachusetts, U.S.A.) in improving adequacy and accuracy of screening and supporting quality control programs.

The investigations were carried out on cervical cytologic smears only. Screening adequacy was assessed through the evaluation of percentage of slide coverage, percentage of overlapping and amount of elapsed time on smears screened with or without the Pathfinder by junior (426 cases) and senior (1,552 cases) screeners. Screening accuracy was investigated by comparing the performances of the same observer when reexamining, with the Pathfinder, a series of 1,051 cases already evaluated without the Pathfinder at least three months earlier. The review process was analyzed by both monitoring the elapsed time for relocation of manually or electronically marked cells (824 fields in 80 smears) and by comparing diagnostic discrepancies after the review of two series (74 + 74 cases) of randomly selected negative cases screened with or without Pathfinder.

Pathfinder-assisted screening increased the number of cases with optimal slide coverage (> or = 90% of screenable area) and optimal overlapping (between 15% and 20%) by both junior (P < .00001 and P < .00001) and senior (P < .00001 and P < .0003) screeners. It also improved screening accuracy by decreasing the number of cases "unsatisfactory for evaluation" (P < .00001) (as a consequence of better coverage and overlapping) and the number of diagnostic discrepancies detected after review (P = .05). During the latter process, the time elapsed for relocation of electronically marked fields, as compared to manually marked ones, was greatly reduced (1 hour, 25 minutes saved for revision of 40 smears).

In these preliminary studies, the Pathfinder was a useful tool for both education and diagnosis (screening and review) in a cytology laboratory.