Discrepancy in the interpretation of cervical histology by gynecologic pathologists.

Objective: To determine if subspecialty review of cervical histology improves diagnostic consensus of cervical intraepithelial neoplasia (CIN).

Methods: After routine histologic assessment within the hospital pathology department, 119 colposcopic cervical biopsies were interpreted by two subspecialty-trained gynecologic pathologists (GYN I and GYN II) blinded to each other's interpretations and to the interpretations of the hospital general pathologists (GEN). Biopsies were classified as normal (including cervicitis), low grade (LG, including CIN I and human papillomavirus changes), and high grade (HG, including CIN II/III). The interobserver agreement rates between GEN and GYN I, between GEN and GYN II, and between GYN I and GYN II were described using the kappa statistic. The proportions of biopsies assigned to each biopsy class were compared using McNemar test.

Results: Interobserver agreement rates between GEN and GYN I were moderate for normal (kappa = 0.53) and LG (kappa = 0.46) and excellent for HG (kappa = 0.76). There were no significant differences in the classifications between GEN and GYN I. Interobserver agreement rates between GEN and GYN II were moderate for normal (kappa = 0.50) and LG (kappa = 0.44) and excellent for HG (kappa = 0.84). Also, GYN II was significantly more likely to classify biopsies as normal (P <.001) and less likely to classify biopsies as LG (P <.001). The interobserver agreement rates between GYN I and GYN II were moderate for normal (kappa = 0.61) and LG (kappa = 0.41) and excellent for HG (kappa = 0.84). Also, GYN II was significantly more likely to classify biopsies as normal (P <.001) and less likely to classify biopsies as LG (P =.01).

Conclusion: Interobserver agreement between two gynecologic pathologists was no better than that observed between general and gynecologic pathologists. Subspecialty review of cervical histology does not enhance diagnostic consensus of CIN.