RU2466392C2 - Method for prediction of cervical cancer in benign and pre-cancer cervical processes in females of reproductive age - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to a method for prediction of cervical cancer in benign and pre-cancer cervical processes in females of reproductive age involving description of clinical risk factors of developing cervical cancer, MLH1, HIC1, RASSF1A, MGMT, N33, CDH1 gene methylation in a cervical biopsy material and calculation of a probability coefficient of developing cervical cancer p. If the value p is more than 0.6, a high probability of developing cervical cancer is predicted, the value p equal to 0.3-0.59 enables predicting a moderate probability of developing cervical cancer, and if the value p is less than 0.29, a low probability of developing cervical cancer is predicted.

EFFECT: method provides more accurate prediction of cervical cancer in benign and pre-cancer cervical diseases in females of reproductive age.

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Description

The invention relates to medicine, in particular to gynecology.

One of the ways to predict cervical cancer is to identify and evaluate the following risk factors: contraceptive methods, the presence of sexually transmitted infection (STI), the presence of high-risk human papillomavirus (HPV), chronic inflammatory diseases of the pelvic organs, numerous abortions, burdened heredity (Kravinskaya T.A .: Therapeutic and diagnostic tactics for benign diseases of the cervix. Diss. ... Ph.D. medical sciences. M., 2009. - 119 p.).

The disadvantage of this method is the low accuracy due to the identification of only clinical and anamnestic risk factors that can diagnose already existing pathological changes, while from the standpoint of oncological alertness it is necessary to identify the earliest markers that determine the likelihood of developing cancer at the earliest possible stage, even before phenotypic formation tumors.

Prediction of cervical cancer based on analysis of gene methylation in squamous cell carcinomas and cervical adenocarcinomas for three RARb-2, TIMP-2, TIMP-3 genes in the presence of HPV infection showed that HPV positive squamous cell carcinomas differ from each other in the number of methylated markers and their combinations. The author notes that the gene methylation profile is unique for each tumor and is evidence that gene methylation is one of the main events in the development of HPV positive squamous cell carcinomas of the cervix uteri (Ivanova T.A. Hypermethylation of DNA in human tumors. Diss ... cand. Biol. Sciences. M., 2004).

The disadvantage of this method is the low accuracy due to the lack of a relationship between clinical and medical history data and genetic studies.

Closest to the proposed method is predicting the development of cervical cancer based on the identification of methylation of the genes p16, CDH1, MGMT, MLH1, Hcl, N33 for cervical dysplasia. The author notes an increase in% methylation in the series: morphologically unchanged tissue adjacent to CIN III (cervical intraepithelial neoplasia according to the classification of Richart RM) → dysplasia (according to the classification JWReagan CIN III - severe dysplasia and CIS), (Podistov Yu.I. Epithelial dysplasia of the cervix (diagnostics, treatment): Diss. ... Doctor of Medical Sciences. - M., 2005. - 246 p.).

The disadvantage of this method of forecasting is the low accuracy, probably due to the determination of methylation of tumor suppressor genes only in samples of the cervical precancer without detailing the degree of the neoplastic process, and also without taking into account benign diseases of the cervix, while epigenetic disorders in the cell genome can occur long before the malignant transformation, not yet detected by morphological examination.

The objective of the invention is a method for improving the accuracy of predicting cervical cancer.

,The problem is solved by a method for predicting cervical cancer in benign and precancerous processes of the cervix uteri in women of reproductive age, including determining methylation of genes in a biopsy of the cervix uteri, the difference of which is the determination of clinical risk factors for cervical cancer, and methylation of genes MLH1, HIC1, RASSF1A, MGMT, N33, CDH1, and calculating the likelihood of developing cervical cancer according to the formula

,

Where:

p is the probability coefficient of the risk of developing cervical cancer;

e is the base of the natural logarithm, equal to 2.7182818282845904;

z = -2.4274 + 2.2163 * X1 + 0.3791 * X1 + 0.528 * X3 + 1.1373 * X4 + 1.2187 * X5 + 2.1587 * X6 + 26.5802 * X7 + 1.3323 * X8 + 1.9323 * X9 + 1.8596 * X10 + 1.6689 * X11 + 1.2123 * X12 + 1.0690 * X13;

X1 - morphotype (benign processes - 1, CIN I - 2, CIN II - 3, CIN III - 4),

X2 - methylation of MLH1 (values: yes - 1, no - 0),

X3 - methylation MGMT (values: yes - 1, no - 0),

X4 - methylation N33 (values: yes - 1, no - 0),

X5 - methylation RASSF1 (values: yes - 1, no - 0),

X6 - methylation of HIC1 (values: yes - 1, no - 0),

X7 - methylation of CDH1 (values: yes - 1, no - 0),

X8 - high-risk HPV (values: yes - 1, no - 0),

X9 - a history of cervical dysplasia (values: yes - 1, no - 0),

X10 - a history of cervical erosion (values: yes - 1, no - 0),

X11 - injuries of the cervix after childbirth / abortion (values: yes - 1, no - 0),

X12 - STI (values: yes - 1, no - 0);

X13 - burdened oncological heredity (values: yes - 1, no - 0),

and with a value of p greater than 0.6, a high probability of a risk of developing cervical cancer is predicted, with p equal to 0.3-0.59, a moderate probability, with p less than 0.29, a low probability. Based on the data obtained, 3 groups of patients can be identified:

- with a low probability of developing cancer - p = 0.0-0.29;

- with a moderate probability of developing cancer - p = 0.3-0.59;

- with a high probability of developing cancer - p = 0.6-1.0.

In practice, the method was carried out as follows. After conducting clinical anamnestic studies, clinical risk factors for cervical cancer were identified: the presence of high-risk HPV, a history of cervical dysplasia, a history of cervical erosion, cervical trauma after childbirth and abortion, an STI, an oncological heredity burdened.

According to the testimony, cervical canal curettage, cervical biopsy was performed. Then part of the biopsy material of the cervix was sent for morphological examination, the other part - in the genetic laboratory. To determine the methylation of suppressor genes, the method of methyl-sensitive polymerase chain reaction (MCH-PCR) was used.

With constant use, the results of the examination were recorded in the Microsoft Office Excel table. Then, individual data of each patient were entered into the cells and the risk of malignant transformation of the cervical epithelium was calculated.

, разработанной на основании изучения клинического и лабораторного материала с учетом бинарной логистической регрессии.The probability of the event was calculated by the formula

developed based on the study of clinical and laboratory material, taking into account binary logistic regression.

The coefficients were calculated on the basis of a comprehensive examination and treatment of 127 patients of reproductive age with benign and precancerous cervical processes. After processing and analyzing the data in Microsoft Excel programs and the Statistica for Windows application package v.7.0, StatSoft Inc. (USA), statistically significant risk factors were determined and their contribution (coefficient in the formula of binary logistic regression) to the likelihood of developing cervical cancer (N. I. Pirogov. Logistic regression. Basic concepts and possibilities of the method. Http: //www.biometrica .tomsk.ru / logit_1.htm).

Sensitivity - 97%, specificity - 90%.

Example 1

Patient K., 27 years old, complained of copious mucous discharge from the genital tract, periodically disturbing itching in the vagina. The examination revealed the following risk factors: a history of chlamydia, cervical erosion, and high-risk HPV. A biopsy of the cervix, curettage of the cervical canal was performed. The morphological diagnosis is ectopia of the cervix, chronic cervicitis. No methylation of suppressor genes has been identified.

Thus: X1 = 1, X2 = 0, X3 = 0, X4 = 0, X5 = 0, X6 = 0, X7 = 0, X8 = 0.59, X9 = 0, X10 = 1, X11 = 0, X12 = 1, X13 = 0.

The probability of developing cervical cancer by the proposed method was p = 0.29, which indicated a low risk of developing cervical cancer.

After conducting etiopathogenetic therapy, lasers vaporization of pathologically altered sections of the cervix was performed. Examination after 6 months did not reveal pathological changes.

Example 2

Patient N., 33 years old, complained of copious mucous discharge from the genital tract. The examination revealed the following risk factors: cervical rupture of 1 tbsp. after childbirth, two abortions, history of cervical erosion of cervical erosion, aggravated oncological heredity, high-risk HPV in a clinically significant concentration. A biopsy of the cervix, curettage of the cervical canal was performed: histoanalysis - cervical ectopia, chronic cervicitis. Methylation of the MLH1, HICl, and RASSF1A genes was detected by MP-PCR.

Thus: X = 1, X2 = 1, X3 = 0, X4 = 0, X5 = 1, X6 = 1, X7 = 0, X8 = 0.65, X9 = 0, X10 = 1, X11 = 1, X12 = 0, X13 = 1.

Estimated p = 0.5, which indicated a moderate risk of cervical cancer.

After anti-inflammatory and antiviral therapy, the patient underwent radio wave destruction of the cervix. Re-examination after 6 months. did not reveal pathological changes.

Example 3

Patient V., 36 years old, complained of copious mucous discharge from the genital tract, periodically “contact” bleeding. The examination revealed risk factors: cervical rupture of 1 tbsp. after childbirth, 3 abortions, laser destruction for mild dysplasia, high-risk HPV, chlamydia, ureaplasmosis. After conducting etiopathogenetic therapy, the patient underwent curettage of the cervical canal, cervical biopsy. Morphologically detected signs of CIN II. Methylation of the N33, HICl, RASSF1, and MLH1 genes was detected by the PCR method.

Thus: X1 = 3, X2 = 1, X3 = 0, X4 = 1, X5 = 1, X6 = 0, X7 = 0, X8 = 0.77, X9 = 1, X10 = 0, X11 = 1, X12 = 1, X13 = 0.

Received p = 0.8, which indicated a high likelihood of developing cervical cancer. The patient was prescribed etiopathogenetic treatment, a radio wave conization of the cervix was proposed. The patient refused the proposed treatment. Re-examination after 6 months. revealed cervical adenocarcinoma.

The method of the invention increases the sensitivity and prognostic value of predicting the risk of developing cervical cancer.

Claims (1)

A method for predicting cervical cancer in benign and precancerous processes of the cervix in women of reproductive age, including determining methylation of genes in a biopsy of the cervix uteri, characterized in that clinical signs and methylation of the genes MLH1, HIC1, RASSF1A, MGMT, N33, CDH1 are determined and the probability is calculated risk of developing cervical cancer according to the formula:

where p is the probability coefficient of the risk of developing cervical cancer;
e is the base of the natural logarithm, equal to 2.7182818282845904;
z = -2.4274 + 2.2163 * X1 + 0.3791 * X2 + 0.528 * X3 + 1.1373 * X4 + 1.2187 * X5 + 2.1587 * X6 + 26.5802 * X7 + 1.3323 * X8 + 1.9323 * X9 + 1.8596 * X10 + 1.6689 * X11 + 1.2123 * X12 + 1.0690 * X13,
X1 - morphotype (benign processes - 1, CIN I - 2, CIN II - 3 CIN III - 4)
X2 - methylation of MLH1
X3 - methylation MGMT
X4 - methylation N33
X5 - methylation RASSF1
X6 - methylation of HIC1
X7 - methylation of CDH1
X8 - High-risk HPV
X9 - a history of cervical dysplasia
X10 - History of cervical erosion
X11 - Cervical injuries after childbirth and abortion
X12 - STI
X13 - burdened oncological heredity,
and with a p value greater than 0.6, a high risk of developing cervical cancer is predicted,
when p is equal to 0.3-0.59, a moderate probability of cervical cancer risk is predicted,
when p is less than 0.29, a low risk of cervical cancer is predicted.