Study On The Application Value Of Sentinel Lymph Node Biopsy In The Treatment Of Cervical Cancer

Objective:Cervical cancer（CC）is a female malignant tumor that is the highest in developing countries.Current CC surgical treatment standard is radical hysterectomy RH)+systematic pelvic lymph nodes dissection（LND）.Due to the nature of tumor cells through lymph nodes（LN）transfer,the pathological state of LN is an important prognostic factor,and this evaluation is currently done by LND.However,about80%-85%of early cervical cancer LN-free violations have accepted unnecessary LND^[1],which can cause lymphatic edema,lymphatic cyst,immune injury,and other complications^[2].With the development of"precision"medical treatment,it is recommended to predict the pathological state of pelvic lymph node（PLN）,which is in theory if the SLN is not transferred,and LND can be omitted^[3].The 2021 NCCN guidelines recommend that^[4]the SLNB has been recommended to have feasibility in early cervical cancer surgery,but for the applicable population,the specific steps of SLNB,such as the choice of tracer,SLN resection process,The necessity and method of ultra-staging detection and the pathological state of SLN are not unconventional.The purpose of this study is through the CNP as a tracer calculating SLN detection rate（DR）detected in CC and analyze its sensitivity（SEN）,accuracy（AC）,specificity（SPE）,negative predictive value（NPV）,false negative rate（FNR）,and analyze the relationship between the DR and clinical pathological features;To routine pathologic examination negative SLNs were detected at the same time the pathological ultra-staging stage detection（PU）to assess the application CNP for assessment of tracer evaluation SLNB in CC the effectiveness of clinical diagnosis of lymph node metastases,discuss the applicable people of SLNB,and explore the SLN pathological condition and the choice of treatment.Methods:In this study,100 cervical cancer patients who underwent sentinel lymph node biopsy and pelvic lymph node resection in our hospital from August 2018 to October2020 were selected as the research objects.Preoperative injection of 1 ml CNP for lymph node mapping in cervix.Identify and record the imaging site and the location of the sentinel lymph node one by one and remove them.Separate the removed sentinel lymph nodes by location.After the sentinel lymph node was removed,the patient underwent open pelvic lymphadenectomy+radical hysterectomy.Randomly selected cases if the lymph node mapping was successful,the SLN was stained with conventional HE,and the negative SLN was subjected to pathological ultra-stage detection of serial sections,and immunohistochemical detection was performed if necessary.If the SLN contains macroscopic metastasis（MAC>2mm）,micrometastasis（0.2mm≤MIC≤2mm）or isolated tumor cells（ITC<0.2mm）,it is considered SLN metastasis is positive.Record all lymph node metastasis and the type of metastasis when SLN is positive.The DR,SEN,SPE,AC,FNR,and NPV of SLN were calculated separately,respectively;simultaneously analyze the impact of clinical features for SLN DR.At the same time,SPSS22.0 is used to analyze and process all data.Results:1、A total of 100 cases of cervical cancer were included in this study,with the age of 22-75 years old;81 of them were squamous cell carcinoma;the FIGO staging was mainly IB1 and IB2;the tumor diameter less than 2.0cm was 39 cases.Among them,10 cases underwent cervical conization before operation and 12 cases received neoadjuvant chemotherapy（paclitaxel+cisplatin）;postoperative pathological results showed that there were 33 cases of LVSI and 40 cases of tumor infiltrating the deep layer of the cervix.2、A total of 2574 lymph nodes were obtained from the study,including 446SLN and 2128 NSLN.At least one SLN was found in 90 patients（90%）,and a bilateral SLN was found in 75 patients（75%）.10 patients failed to map SLN,7 of them had LVSI,6 had tumor diameter≥4cm,and 4 had a history of NACT before operation.SLN mostly occurs in the pelvis along the iliac vessels or the obturator space,and SLN is more common in the obturator（46.0%）,internal iliac（28.5%）and external iliac（20.2%）areas.3、85 of pelvic lymph node negative cases,15 cases of pelvic lymph node metastasis,of which 14 cases of SLN had metastasis,and 1 case was found by routine pathological examination of failure of SLN imaging.There were 76 cases with negative SLN pathology and no NSLN metastasis.There were no false negative cases of SLN negative and NSLN positive.The sensitivity of SLNB is 93.3%（14/15）,the specificity is 89.4%（76/85）,the accuracy is 100.0%（90/90）,the negative predictive value is 100%（76/76）,and the false negative rate is 0.0%（0/15）。4、The detection rate of SLN was higher in patients with tumor size（<2.0cm）and without lymphatic vascular invasion,which were 94.9%and 95.5%,respectively.And the detection rate of SLN was the lowest in patients with preoperative neoadjuvant chemotherapy,only 66.7%.FIGO staging（stage II）,tumor size（≥2cm）,body mass index（>30kg/m2）,preoperative neoadjuvant chemotherapy,lymphatic vascular invasion,deep invasion all reduced the detection rate of SLN.After statistical analysis,preoperative neoadjuvant chemotherapy（p=0.021）and lymphatic vascular infiltration（p=0.023）reduced the detection rate of SLN and was statistically significant.5、Among the 15 patients with positive pelvic lymph nodes,10 had lesions detected by HE staining,and 5 cases had lesions detected by pathological ultra-staging.Among the 14 SLN-positive patients,a total of 16 SLNs metastasized,including 11 SLNs with MAC metastases,;4 SLNs were MIC metastases,1 SLN was ITC metastases.The detection rate of HE staining for lymph node MAC metastasis was 10%,the detection rate of MIC/ITC by pathological ultra-staging was10.2%,and the detection rate of lymph node metastasis by conventional pathological staining combined with pathological ultra-staging technology was 18.3%.Conclusion:1.SLN biopsy combined with CNP tracer is feasible in the treatment of cervical cancer,and has high sensitivity in predicting pelvic lymph node metastasis,especially for FIGO stage I,tumor diameter<2cm;for patients with tumor diameter≥4cm should be cautiously treated with SLNB;2.SLN with negative pathological HE examination should undergo pathological ultra-staging to improve the detection rate of micrometastasis and isolated tumor cells;3.The detection rate of SLN is related to the clinical characteristics and tumor-related factors of the patient.The detection rate of SLN is high in cases with a diameter of<2cm and without LVSI,while preoperative neoadjuvant chemotherapy and the presence of lymphatic vascular infiltration to reduce the detection of SLN are statistically significant;4.SLNs are mostly distributed in the obturator,internal and external iliac regions;5.There is no metastasis in NSLN when the SLN PU test is negative.Therefore,for cervical cancer patients with bilateral SLN development and negative sentinel lymph nodes in PU,LND can be ommitted and only SLN biopsy is feasible;6.When the SLN has a MAC（>2 mm）,the probability of NSLN metastasis is higher and should be performed LND;when SLN has MIC or ITC,NSLN does not have metastasis,it’s considerable to perform only SLNB instead of LND.