# Cervical Cancer Diagnostics Using Machine Learning Algorithms and Class Balancing Techniques
## 2 Standard Cervical Cancer Diagnostic Procedure and AI-Based Tentative Screening
### Standard Cervical Cancer Screening and Colposcopy  
The initial step in the diagnosis of cervical cancer is based on several screening methods, of which the most common are:  
* Papanicolaou (PAP) test,
* Liquid-Based Cytology (LBC),
* HPV-DNA testing. A PAP test is a cytological method in which the gynecologist uses a wooden spatula and a wooden stick wrapped in cotton wool to take a swab from the posterior arch of the \begin{table}
\begin{tabular}{l l l l l l} \hline \hline
**Article** & **Method** & **Biopsy** & **Cytology** & **[PERSON]** & **[PERSON]** \\ \hline
[24] & RF + SMOTE & \begin{tabular}{l} \(TPR\) = 0.93; \\ \(TNR\) = 0.98 \\ \(Acc\) = 0.96 \\ \end{tabular} & \begin{tabular}{l} \(TPR\) = 0.98; \\ \(TNR\) = 0.99 \\ \(Acc\) = 0.97 \\ \end{tabular} & \
\begin{tabular}{l} \(TPR\) = 0.96; \\ \(TNR\) = 0.98 \\ \(Acc\) = 0.97 \\ \end{tabular} &
\begin{tabular}{l} \(TPR\) = 0.93; \\ \(TNR\) = 0.98 \\ \(Acc\) = 0.97 \\ \end{tabular} \\ \hline
[26] & XGBoost & \(F1\) = 0.96 & \(F1\) = 0.94 & \(Acc\) = 0.98 & \(Acc\) = 0.96 \\ \hline
[27] & RF & \(Acc\) = 0.98 & \(Acc\) = 0.98 & \(Acc\) = 0.99 & \(Acc\) = 0.98 \\ \hline
[28] & RF + SMOTE & \begin{tabular}{l} \(TPR\) = 0.97; \\ \(TNR\) = 0.97 \\ \end{tabular} & \begin{tabular}{l} \(TPR\) = 0.98; \\ \(TNR\) = 0.98 \\ \end{tabular} & \
\begin{tabular}{l} \(TPR\) = 0.96; \\ \(TNR\) = 0.95 \\ \end{tabular} &
\begin{tabular}{l} \(TPR\) = 0.97; \\ \(TNR\) = 0.97 \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: A brief overview of the state-of-the-art methods and results (\(TPR\)—true positive rate, \(TNR\)—true negative rate, \(Acc\)—Accuracy, \(F1\)—\(F1\)-score). cevix, the cervical part of the cervix, and the cervical canal. The swab is transferred from a wooden spatula and stick to a glass slide that is immersed in alcohol to fix (preserve) the cells, and is stained using a special method so that the taken cells can be analyzed microscopically [29]. LBC is a cytological analysis performed to detect the changes that precede cervical cancer. The main difference between LBC and PAP is the application of the cells to the glass using a conservation solution. Such a sample is more suitable for analysis because it does not contain blood, mucus, and inflammatory cells [30]. HPV-DNA is a diagnostic method where the cervix is visualized with a speculum, and a sample is taken from the cervical canal with a swab that has a cotton head or a brush, and delivered to the laboratory in a transport medium. The sample's DNA is analyzed to determine if the patient has been infected with an HPV type that correlates with cervical cancer occurrence [31]. The \(TPR\) and \(TNR\) rates achieved with PAP, LBC, and HPV-DNA methods are reported in multiple research and review papers [32; 33; 34; 35]. The comparison of maximal \(TPR\) and \(TNR\) rates are presented in Figure 1. If the \(TPR\) and \(TNR\) rates achieved with PAP, LBC, and HPV-DNA are compared with state-of-the-art survey-based methods presented in Table 1, and it can be seen that survey-based methods are achieving similar and even higher results. To confirm the diagnosis based on the results of the screening procedure, a colposcopy is performed. Colposcopy is a method of observing the surface of the cervix with a magnification of 6-40 times. It is an examination method for the vulva, vagina, and cervix. Colposcopy is performed with the help of a colposcope--a specially designed mobile microscope with a magnification of 2-40 times. Depending on whether the neck of the uterus (cervix) and vagina (Greek kolpos) are observed, the method is called colposcopy or vulvoscopy (if the external genitalia (vulva) is observed). A data flow of a colposcopic diagnostic procedure is presented in Figure 2.  
Simple or native colposcopy means the simple observation of the cervix, and extended colposcopy implies the use of optical or chemical aids. The optical aid is a green filter that particularly improves the visualization of blood vessels on the surface of the cervix.