Hans Hinselmann invented colposcopy in 1925. It is a realtime visualization of the cervix, with magnification and illumination, especially the transformation zone for the detection of cervical intraepithelial neoplasia (CIN) and invasive cancer. It is also used for vaginal or vulvar evaluation. The basis for colposcopy is to find suspicious lesions and biopsy through 3–5% acetic acid and Lugol iodine solution. The acetowhite epithelium, lesion borders and size, vascular patterns, crypt openings and ect are visualized [6, 8, 12, 13]. Before colposcopy was widely used, many women with serious cytological abnormalities underwent conization or hysterectomy as both diagnosis and therapy. The application of colposcopy with targeted biopsies provided accurate assessment and unnecessary excision was avoided [14, 15].
With the purpose of unifying the nomenclature of colposcopy for comparative studies and improving the accuracy of diagnosis, IFCPC presented its first International Colposcopic Classification in 1975, its second nomenclature in 1990 and third in 2002. In 2011, the IFCPC committee examined the past IFCPC terminologies and proposed an evidence-based terminology by reviewing publications. It was recommended that the 2011 terminology should replace all other terminologies and be implemented immediately for diagnosis, treatment and research [12]. So far, the 2011 IFCPC terminology has been proposed for several years. It has certain clinical practicability. Several studies demonstrated it can improve the colposcopic accuracy. However, the reproducibility of transformation zone and the predictive value of a few signs remained to be questioned. Meanwhile, with the popularized of HPV vaccine and changes in cervical cancer screening strategies, colposcopy presents new challenges. First, long-term effects of HPV vaccination has leaded to decreased the incidence of high grade CIN in Australia, America and Europe. It will be the trend in developing country, such as in china. In addition, the update of the guidelines tends to reduce the screening of low-risk women with longer intervals [16–19]. The impact of vaccination and referral patterns may lead to a trend of colposcopy volume reduction. This was confirmed in a study in the United States, which showed that the average monthly visits (75.3) dropped to nearly one-third of the 218 visits per month in July 2010. [20]. Secondly, cytology-based screening is being replaced by HPV-based screening. In HPV-screening with higher sensitivity than cytology, the number with minor abnormalities at colposcopy is likely to increase. Otherwise, colposcopic signs of HPV-16 infection are more typical than other types of HPV infection [16]. This was confirmed in other studies [21, 22]. In the vaccinated and HPV-based screening population, colposcopy may become increasingly difficult [23]. Recognizing the limitations of the terminology, in 2017 ASCCP presented recommendations for colposcopy practice and procedures and the quality assurance measures in America [24, 25]. ASCCP claimed 2017 ASCCP terminology was compatible with the IFCPC terminology and was an adapted and simplified version. Although some changes were obvious, such as removal of the classification of cervical transformation zone and emphasis of risk-based colposcopy practise. Of course, ASCCP also expressed their expectation to continue constructive dialogue with IFCPC [26]. We would like to see such kind of academic controversy because it leads to thinking and problem solving. The world health organization has set a goal of eliminating cervical cancer worldwide by 2030. This year, the 17th World Congress for Cervical Pathology and Colposcopy will be held in India. The theme is “Eliminating Cervical Cancer all for Action”. A new edition of IFCPC colposcopy terminology will be released. Of the moment, we conclude, look ahead, explore the likely changes of colposcopy practice in this era because no matter which screening program is selected, colposcopy will still be the tool for diagnosing precancerous lesions after the screening is positive [23]. Therefore, colposcopic skills and basic training are still very important [27].
In this study, we analyzed the clinical applicability of the 2011 IFCPC nomenclature in predicting cervical disease. The results showed the agreement between histopathology and colposcopy was 65.07% with weighted kappa = 0.5966. It was equal to Li et al’s of 64.95% with consistency of kappa = 0.436, Fan et al’s of 65.5% with weighted kappa strength 0.494 and Prabhakaran’s of 65.7% [28–30]. Although IFCPC nomenclature was only moderate, it was better than Swede Score, RCI, modified RCI and 2002 IFCPC nomenclature [7, 8, 31–35]. In our study, we found that the 2011 IFCPC colposcopic terminology had a high sensitivity (92.72%) in differentiating HSIL+ from LSIL−, a little higher than that reported in previous studies (30–91.3%) [36]. The specificity for detecting HSIL+ was 78.86%, a little lower than previously reported (79–96.5%) [34, 37, 38]. The PPV and NPV of colposcopy to diagnose HSIL+ were 89.72% and 84.49%, both comparable to the previous findings [34, 36–38]. The term of cervical colposcopy in 2011 begins with “general assessment” with the purpose of emphasizing the level of reliability of this colposcopic examination [12]. In our study, 1.25% (147/1838) of all patients had inadequate colposcopic examination. The main reason was bleeding, others included scarring of lacerations, vaginal wall relaxation, changes in cervical position (hysteromyoma compression, adhesion), inflammation and neoplasm. This reminds us colposcopic operation should be gentle, so as not to artificially caused contact bleeding, especially near the endocervical canal. For changes in cervical position, we can use tools such as cervical clamp when necessary to help fully exposing the cervical transformation zone. If there is cervical neoplasm, it should be pushed in different directions in order to see the transformation zone at 360°. The squamocolumnar junction was completely visible in 334 (334/1838, 18.17%). “Partially visible” and “not visible” are respectively defined as mostly visible and most or all invisible of the squamocolumnar junction because it is in the endocervical canal. We think the definitions of “partially visible” and “not visible” are ambiguous. The degree of “most of the squamocolumnar junction visible and not visible” is difficult to grasp. We suggest the visibility of squamocolumnar junction in the range of 0°–360° is defined as “partially visible” with visible rang indicated as necessary. For example, the squamocolumnar junction is partially visible from 90° to 180°. It is also suggested “not visible” means the squamocolumnar junction can not be seen at all.
Once the highlight but now the controversy of 2011 IFCPC nomenclature is cervical TZ. The authorsʼ supposition of TZ is that it advances a closer relationship to therapeutic strategies and leads to individualized treatment [39]. Type1, 2, 3 excisions with removal of different rang of ectocervical and endocervical tissue resect type 1, 2, 3 TZ. However, in clinical practice of several years, the reproducibility of TZ in different examiners has been questioned. In this study, transformation zone types 1, 2, 3 accounted for 16.81% (309/1838, 16.81%), 1.36% (25/1838, 1.36%) and 81.83% (1504/1838, 81.83%). Li et al’s study of 525 cases indicated types 1, 2, and 3 of TZs accounted for 22.29%, 7.24%, and 70.48% [28]. Fan et al’s research showed 1005 cases (44.4%, 1005/2262) were classified as type 2 TZ, 887 (39.2%, 887/2262) as type 1 and 370 (16.4%, 370/2262) as type 3 TZ [29]. It was significantly different between the distributions of the three types TZ in our and Fan et al’s studies, especially of type 2 TZ. In the Germany analysis of 3761, 2153 cases (57%) were classified as type 2 TZ, 906 cases (24%) were type 1 TZ, 702 cases (19%) were type 3 TZ, and significant heterogeneity of TZs in different clinics was showed [40]. In 2017, ASCCP claimed that literature suggested the use of TZ type unrepeatable, especially for type 2 TZ, and there was no evidence showed TZ type can improve the prediction or management of cervical disease [35, 40]. Therefore, TZ types were not incorporated in the 2017 ASCCP terminology. We suggest on one hand, more studies should focus on the precise extent especially the “length” of excision for different TZ types, the necessity of existence of type 2 TZ and more precise anatomic distinction between types 1 and 2 TZ. On the other hand, if evidence-based research suggests that the TZ has clinical significance, further effort to reduce heterogeneity in the classification of TZ types between individual examiners is of importance. The squamocolumnar junction is the inner margin of cervical TZ. Correctly identifying the mature columnar epithelium and then confirming the squamocolumnar junction is the key to correctly identifying the TZ.
Acetowhite epithelium is a core finding in colposcopy. Dense aceto-white epithelium had good specificity, PPV and NPV for HSIL. Major changes such as coarse mosaic, coarse punctuation, cuffed crypt openings and sharp border all had high specificity for HSIL. Two new signs, inner border sign and ridge sign also showed good diagnostic value. Compared with the major changes, the diagnostic value of minor changes signs was not satisfactory. The specificity of thin aceto-white epithelium was 59.02% and PPV 53.15%. The sensitivity of fine punctation and fine mosaic were quite low. It should be pointed out that the definition of the dense or thin aceto-white is subjective and relative, which should be combined with the type of HPV infection, the patient's age and so on. Massad et al. suggested all acetowhite lesions should be biopsied to improve sensitivity [32]. ASCCP recommended that for high-risk screening results, the biopsy of mild or translucent acetowhite changes was also necessary [25]. Actually, several signs such as punctation, mosaic, sharp border and even the new signs of both major and minor changes were highly specific and less sensitive because they occurred less frequently in cases. This makes them less diagnostic in daily clinical practice. Therefore, we attempted to find a sign with high frequency as acetowhite changes. As we all know, the significance of Lugol’s staining was diminishing, from major changes section, minor changes section to the “nonspecific” category of the “abnormal colposcopic findings” section in 2011 Colposcopic Terminology. Our study confirmed Lugol’s staining negativity had a high sensitivity and NPV while the specificity was low. Although we suggested Lugol’s staining was useful in delineating the boundaries of normal and abnormal tissue, identifying vaginal lesions and lesions of no obvious acetowhite changes after menopause. Lugol’s staining had high NPV. Lugol’s staining negativity was divided into bright and mustard yellow. We investigated the diagnostic value of bright yellow for LSIL and mustard yellow for HSIL. As a result, mustard yellow may be a valuable indicator for the diagnosis of HSIL. We believe Lugol’s staining still has certain diagnostic value of colposcopy and is the necessary procedure in colposcopic performance.