[Discrepancy between histopathological diagnosis based on guided biopsy and cone biopsy of the cervix uteri: analysis of 346 cases of laser conization].
The conservative management of cervical intraepithelial neoplasia (CIN) essentially depended on the introduction and improvement of colposcopy. This technique, allowing to locate the lesion, to estimate its extension and to perform multiple punch biopsies, becomes discriminant in therapeutic choice. Whether colposcopy reveals endocervical involvement or abnormal transformation zone (ANTZ) may be only partially explored, excisional conization should be preferred to ablative therapy since the former advantageously can verify histopathologic diagnosis, confirm completely excision of lesion and rule out invasive carcinoma. The literature shows that cases of invasive lesions can be underestimated and therefore inadequately treated by ablative therapy, emphasizing colposcopy and punch biopsy limitations about suspect and diagnosis of microinvasion. We analyzed data concerning preliminary diagnostic investigations and results of 346 CO2 laser excisional conizations performed between 1984 and 1993. Histopathologic diagnosis on punch biopsy, performed in 111 cases of ANTZ1 and in 235 cases of ANTZ2, shows an agreement with cone biopsy in 30.8% of the cases of CIN1, of 40.9% in cases of CIN2 and of 66.3% in cases of CIN3. Whereas the lesion is overestimated in 30.6% of cases, in which it is likely that punch biopsy has removed the epicenter of the lesion or the lesion in toto, we had an underestimation in 15% of cases, particularly in 4 cases of CIN2, in 38 cases of CIN3 and in all microinvasive processes. The rate of invasive lesions previously ignored and detected only by histopathologic diagnosis on cone biopsy is 2.9%. In only one of these cases colposcopy, even if attributing to each of these the higher grading, shows the suspicion of invasion, whereas the detection of invasive processes is missed in every case by punch biopsy.(ABSTRACT TRUNCATED AT 250 WORDS)