OBJECTIVE: To investigate the clinical efficacy of cryosurgery on cervical high-risk human papilloma virus (HPV) infection.
METHODS: Eighty patients with high-risk HPV infection combined with different degrees of cervical lesions were treated with cryosurgery, and the levels of cervical HPV-DNA were quantified by hybridization capture second-generation method before and 3 and 6 months after surgery, and colposcopy and cervical biopsy were performed.
RESULTS: The differences in preoperative HPV levels between different CIN grades were not significant (p > 0.05). The cervical high-risk HPV was detected 3 months after surgery, and 39 cases turned negative, with a conversion rate of 48.75% (39/80); 6 months after surgery, 65 cases turned negative, with a conversion rate of 81.25% (65/80); 15 cases remained positive, and these positive cases were retested for HPV after 3 months (9 months after surgery), and 9 cases turned negative; 6 cases (7.5%) did not decrease but increased instead (6/80), there were 6 cases in which the HPV load increased instead of decreased after cryotherapy, and there were 3 cases in which colposcopy biopsy of CIN did not escalate, and 2 cryosurgery was performed and HPV was reexamined 3 months after surgery and all turned negative. The other 3 cases with pathological findings of CIN grade escalation underwent cervical Leep and were tested for cervical high-risk HPV 3 months postoperatively, all of which also turned negative.
Conclusion: Cryosurgery is an effective treatment for cervical precancerous lesions, clearing cervical HPV infection and reducing the incidence of cervical cancer.
Cervical cancer is the most common malignant tumor of the female reproductive tract, and epidemiological data from various countries show that the incidence and mortality rate of cervical cancer are increasing, and its incidence is the second highest among female malignant tumors after breast cancer. Studies over the past 20 years have demonstrated that the occurrence and development of cervical cancer are directly related to persistent infection with human papillomavirus (HPV), which can be detected in 99% of cervical cancer tissues [1~2]. The HC-2 method, which was developed in recent years, uses standardized kits for the direct detection of high-risk HPV types and has high sensitivity for cervical cancer screening. However, at present, there is no clear and effective treatment for cervical HPV infection, so the diagnosis and treatment of HPV are of utmost clinical importance in preventing and reducing the occurrence of cervical cancer. In this study, patients with high-risk HPV infection combined with different degrees of cervical lesions were subjected to cryosurgery, and HPV DNA tests were repeated at 3 and 6 months after surgery to observe the therapeutic effect of cryosurgery on patients with high-risk HPV infection.
Clinical data and methods
1.Study population.
Women with abnormal cervical liquid-based cytology (≥ASC or above lesions) who attended the gynecology cervical clinic from April 2006 to February 2007 and underwent HC-II test to confirm high-risk human papillomavirus (HPV) infection, and women who were positive for both TCT and HPV then underwent colposcopic multi-point biopsy of cervical tissue. All women gave informed consent and completed a specially designed questionnaire that included questions and answers about the patient’s general condition and risk factors for cervical cancer. Clinical and pathological information was then obtained from the pathology report and a form completed by the clinician.
The data were obtained from 80 cases, aged 22-57 years, with an average of 33.6 – years, of which 63.75% were ≤35 years old. There were 39 cases of menstruating mothers and 41 cases of uncomplicated mothers. The number of pregnancies ranged from 0 to 6, and the number of deliveries ranged from 0 to 2. The age of first intercourse was 18-27 years old, with an average of 22.35 years. The number of sexual partners ranged from 1 to 4, with an average of 1.48.
The complaints at the initial consultation included abnormal cervical cytology [Pap smear with nuclear heterogeneity and thinPrep cytology test (TCT): atypical squamous cells (ASC), etc.], abnormal vaginal discharge, and contact bleeding.
2.Methods
2.1, Cervical cytology test.
After filming with TCT (ThinPrep) ultra-thin liquid-based cytology method, all the films were read and reported by specialized cytologists. Diagnosis of cervical cytopathology: According to the 2004 TBS grading system recommended by the International Cancer Society, the diagnosis of cytologic abnormalities involved in this study included: atypical squamous epithelial cells without clear significance (ASCUS), atypical squamous epithelial cells without exclusion of high squamous intraepithelial lesions (ASC-H), low grade squamous intraepithelial lesions (LSIL), high grade squamous intraepithelial lesions (HSIL). intraepithelial lesions (HSIL).
2.2. High-risk HPV (HR-HPV) testing.
Sample collection: Use the special HPV sampler provided by Digene USA, insert it into the ectocervix by turning clockwise for 5 turns, and slowly remove the sampler into the vial of preserved fluid.
Test method: The HC 2nd generation hybridization capture test provided by Digene USA was used to detect the HPV DNA content in the sample, which is used to indicate the HPV load. HC-2 uses a 96-well plate method to detect 13 types of high-risk HPV DNA at one time. including 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 68. The criteria for HPV DNA positivity are: HPV DNA ≥1.0pg/ml is a positive result, suggesting one or more high-risk HPV infections, <1.0 is negative.
2.3. Colposcopic multi-point biopsy pathological histological examination methods.
All positive patients with both TCT and HPV were subjected to colposcopic multi-point biopsy of cervical tissues. The pathological diagnosis included: normal or inflammatory cervical 8 cases, CINⅠ50 cases CINⅡ22 cases.
2.4, Indications for cryotherapy.
①, abnormal cytology, human papillomavirus (HPV) infection and colposcopy results suggesting cervical inflammation or cervical precancerous lesions.
②, lesions are small enough to be covered by the cryoprobe and the lesion edge is less than 2mm beyond the probe edge.
(iii) The lesion border is clearly visible and does not involve the cervical canal and vaginal wall.
2.5. Cryotherapy methods.
2.5.1, Instrument: Erbokryo CA multifunctional cryotherapy instrument was used.
2.5.2. Preoperative preparation: Except for menopausal patients, the treatment time is chosen 2-7 days after menstruation. Preoperative pelvic examination should be normal, and routine discharge examination should be performed to exclude acute or specific infections of the reproductive tract such as mycobacteria, trichomonas and bacterial vaginitis.
2.5.3. Surgical method: The patient is placed in a bladder amputation position, routinely disinfected, and after exposing the cervix, a highly refrigerated metal probe (cryoprobe) is placed in contact with the cervix and the surface of the cervix is frozen using CO2 gas. For each treatment, the cryoprobe is placed in contact with the cervix twice, for 3 minutes each time. An interval of 5 minutes is used for thawing in between (double freezing technique).
2.6. Postoperative management and follow-up of cryotherapy.
Prohibit sexual intercourse for two months after surgery and pay attention to vulva cleanliness. Follow-up date: 1, 2, 3 and 6 months after surgery. Observe the wound repair, vaginal bleeding and discharge in the first and second months. In the third and sixth months, TCT, HPV DNA and colposcopy were repeated. If HPV DNA did not decrease but increased, multi-point colposcopic cervical biopsy was performed again to re-evaluate the cervical lesions.
3. Statistical processing
All data were processed using the SPSS10.0 software package, and the x2 test was used, with a significant difference threshold of p < 0.05.
Results
1, Clinical distribution of HPV infection: The peak age of this data group was in the age group of 25-35 years old and decreased significantly in the age group of 50-55 years old; while HPV infection peaked in the age group of 25-30 years old and decreased significantly in the age group of 40-45 years old.
2. Clinical manifestations of HPV: 35 cases with abnormal leucorrhea, accounting for 43.75%; 14 cases complaining of contact bleeding, accounting for 17.5%; 2 cases with acromegaly of the lower genital tract, accounting for 2.5%; 29 cases without clear symptoms, accounting for 36.25%. The gynecological examination of the cervix was smooth in 28 cases, mild erosion in 28 cases, moderate erosion in 18 cases, severe erosion in 5 cases, and cervical polyp in 1 case. Cervical pathology diagnosed 8 cases of cervicitis, 50 cases of CINⅠ and 22 cases of CINⅡ.
The relationship between HPV and sexual activity: the mean age of first intercourse in HPV patients was 22.4. The mean age of first intercourse in the age group ≤35 years was 5 years earlier than that in the age group above 35 years. There were 46 cases of multiple sexual partners, accounting for 57.5%, and multiple sexual partners were mainly concentrated in the <25 years age group.
4/ Preoperative HPV levels before cryopreservation for different degrees of cervical lesions
Preoperative HPV CDNA content 1.00-9.99: normal or inflammation 0 cases, CINⅠ10 cases, CINⅡ1 case; content 10.00-99.99: normal or inflammation 1 case, CINⅠ9 cases, CINⅡ2 cases; content 100.00- 999.99: 6 cases of normal or inflammation, 17 cases of CINⅠ, 13 cases of CINⅡ; content ≥1000: 1 case of normal or inflammation, 14 cases of CINⅠ, 6 cases of CINⅡ. There was no significant difference in the preoperative HPV content of different CIN classifications (p＞0.05).
5. HPV conversion and load decrease at 3 and 6 months after cryosurgery
The mean HPV CDNA content was 598.62 in 80 patients before cryosurgery, 167.26 in 3 months after surgery, and 74.83 in 6 months after surgery. 80 cases were tested for cervical high-risk HPV at 3 months after surgery, 39 cases turned negative and 41 cases remained positive, with a conversion rate of 48.75% (39/80). Six months after the operation, 65 cases were tested for cervical high-risk HPV and became negative, with a conversion rate of 81.25% (65/80); 15 cases were still positive, and these positive cases were re-examined for HPV after 3 months (9 months after the operation), and 9 cases became negative; 6 cases, 7.5% (6/80), did not decrease but increased, and 3 cases were re-examined vaginally and biopsied, and the pathological results did not escalate to other changes. In the other 3 cases, the pathological results were upgraded to CINⅠ or CINⅡ, and cervical deepening was performed, and the cervical high-risk HPV was detected 3 months after surgery, and all of them turned negative. The differences in HPV conversion and load changes at 3 and 6 months after surgery for different CIN grades were not significant (p > 0.05).
Discussion
Persistent HPV infection has been epidemiologically and biologically proven to be a necessary factor in causing cervical cancer and precancerous lesions [3], and the risk of disease in HPV-negative individuals is almost zero. Our data show that HPV infection is more common in young women, with the peak age of infection at 25-30 years, suggesting that the trend of younger HPV infection cannot be ignored, which is associated with earlier sexual life, active sexual life and unstable sexual partners. However, the rate of cervical HPV infection decreases significantly with age, and the rate of HPV infection at age ≥55 years is only 1.25%, which may be related to the low immune function to clear HPV. HPV infection can cause epithelial cells to acquire high proliferative activity, and may also promote cancer by promoting the transitional proliferative activity of epithelial cells. Most women spontaneously clear HPV infection, but about 10-15% of women over 35 years of age still have persistent infection, and those with persistent HPV infection are at high risk of cervical cancer [5].
Problems in the management of HPV infection:At present, there is no clear and effective clinical treatment for cervical HPV infection. In our data, all 80 cases had high-risk HPV infection with different degrees of cervical precancerous lesions. However, the difference in preoperative HPV content between different CIN grades was not significant, and there were also those with extremely high HPV content in cervical inflammation or CIN Ⅰ. Therefore, the pure pathological CIN examination cannot fully reflect the HPV load, and the determination of HPV content should be paid attention to. 80 patients were treated with cryotherapy, and the HPV test was performed after 3 months, and the conversion rate was 48.75%, and the HPV load was significantly decreased, and 6 months The HPV test again, the conversion rate was higher, 81.25% %, and those who still did not convert, the HPV load decreased more significantly, showing that cryosurgery has significant clinical efficacy for cervical HPV infection. The results suggest that cryosurgery has very positive implications for the treatment of cervical lesions with high-risk HPV infection. While treating cervical precancerous lesions, it clears HPV infection, blocks further development of cervical lesions, and reduces the occurrence of cervical cancer. In our data, there were 6 cases in which the HPV load did not decrease but increased after cryotherapy, and 3 cases in which the CIN did not escalate by colposcopy biopsy again, 2 cryosurgery was performed and the HPV was rechecked 3 months after surgery and all turned negative. The other 3 cases with escalated CIN grade on pathology, underwent cervical Leep and were tested for cervical high-risk HPV 3 months after surgery and all also turned negative. This situation may be related to residual lesions, recurrence or repeated infections, and is subject to further study and investigation.
Cervical cryotherapy is the use of low-temperature freezing medical machine to quickly generate ultra-low temperature, so that the local lesion tissue of the cervix freeze, the intracellular fluid freeze to form ice crystals, cell dehydration, electrolyte concentration increases, protein denaturation, local capillary blockage, microcirculation stopped, the frozen area occurs in a comprehensive ischemia, necrosis, hyaline change so that the necrotic tissue off, freezing rewarming process also has a destructive effect on tissue. Cryosurgery can be controlled by foot pedal, easy to operate, the operation can be carried out in the outpatient clinic, no anesthesia, no pain; treatment time is short, no odor during treatment; decab evenly without bleeding, no stimulation of tissue proliferation; not easy to cause cervical stenosis and adhesion, the group of 80 cases follow-up are more than 6 months, no case of intraoperative and postoperative complications.
In conclusion, cryosurgery is an effective treatment for cervical precancerous lesions, clearing cervical HPV infection and reducing the incidence of cervical cancer.