Sentinel lymph node biopsy in cervical cancer: A meta-analysis

Benefits of sentinel node detection in cervical cancer

PURPOSE OF REVIEW

Sentinel lymph node biopsy (SLNB) is a widely used technique in other gynaecological tumours but has not yet been implemented as the gold standard technique for nodal staging in cervical cancer. Since the majority of evidence is derived from retrospective studies, this review aims to summarize the most recent evidence on this relevant topic.

RECENT FINDINGS

SLNB has demonstrated to be a well tolerated technique for lymph node staging in early-stage cervical cancer patients with promising future as exclusive lymph node assessment method avoiding full lymphadenectomy. Moreover, it allows ultrastaging and unfrequent drainage identification, which enables the detection of patients at a high risk of recurrence who would otherwise remain unnoticed. When compared with pelvic lymphadenectomy, SLNB is also associated with less intraoperative and postoperative complications, especially in terms of lymphedema formation.

SUMMARY

The available evidence suggests that SLNB offers numerous advantages over the standard pelvic lymphadenectomy reducing morbidity rates and increasing diagnostic accuracy. Three ongoing prospective trials will likely answer the controversies over these questions.

Cervical cancer: a new era

Cervical cancer is a major global health issue, ranking as the fourth most common cancer in women worldwide. Depending on stage, histology, and patient factors, the standard management of cervical cancer is a combination of treatment approaches, including (fertility- or non-fertility-sparing) surgery, radiotherapy, platinum-based chemotherapy, and novel systemic therapies such as bevacizumab, immune checkpoint inhibitors, and antibody-drug conjugates. While ambitious global initiatives seek to eliminate cervical cancer as a public health problem, the management of cervical cancer continues to evolve with major advances in imaging modalities, surgical approaches, identification of histopathological risk factors, radiotherapy techniques, and biomarker-driven personalized therapies. In particular, the introduction of immune checkpoint inhibitors has dramatically altered the treatment of cervical cancer, leading to significant survival benefits in both locally advanced and metastatic/recurrent settings. As the landscape of cervical cancer therapies continues to evolve, the aim of the present review is to provide a comprehensive discussion of the current state and the latest practice-changing updates in cervical cancer.

Effectiveness of sentinel lymph node biopsy and bilateral pelvic nodal dissection using methylene blue dye in early-stage operable cervical cancer-A prospective study

OBJECTIVE

To evaluate the effectiveness of methylene blue dye in detecting sentinel lymph nodes (SLNs) in women with early-stage operable (defined as FIGO I-IIA) cervical cancer. It also aims to evaluate procedural challenges and accuracy.

METHOD

This prospective study, which focused on 20 women with early-stage cervical cancer, was carried out between June 2016 and December 2017. These patients had SLN mapping with methylene blue dye injections and thorough examinations, including imaging. All patients underwent radical hysterectomy and complete bilateral pelvic lymphadenectomy. No additional investigation was done on the lymph node in cases where a metastasis was found in the first H&E-stained segment of the sentinel node.

RESULT

20 patients were included in the analysis. The median age of the subjects was 53, and 95 % of them had squamous cell carcinoma. 90 % of the time, the identification of SLNs was effective, and 55 SLNs were found, of which 52.7 % were on the right side of the pelvis and 47.3 % on the left. The obturator group had the most nodes, followed by the external and internal iliac groups in descending order of occurrence. Metastasis was detected in 3 patients, resulting in a sensitivity of 100 % and a specificity of 93.75 % for SLN biopsy. Notably, no false-negative SLNs were found. Complications related to methylene blue usage included urine discoloration in 30 % of patients.

CONCLUSION

This trial highlights the promising efficacy and safety of methylene blue dye alone for SLN identification in early-stage operable cervical cancer, with a notably higher success rate. Despite limitations like a small sample size, healthcare professionals and researchers can build upon the insights from this study to enhance cervical cancer management.

Emerging Treatment Options for Cervical Dysplasia and Early Cervical Cancer

DISCUSSION

of treatment strategies for cervical cancer precursors, review of medical therapies and emerging therapeutics for treatment of cervical cancers, and updates on new approaches to treating early-stage cervical cancers.

Clinical Study of Sentinel Lymph Node Detection Using Photodynamic Eye for Abdominal Radical Trachelectomy

This study aimed to assess the accuracy of predicting pelvic lymph node status using sentinel lymph node (SLN) biopsy with indocyanine green (ICG) and to examine the outcomes of SLN biopsy-guided abdominal radical trachelectomy (ART). Patients with stage IA2-IB2 cervical cancer from January 2009 to January 2021 were included. ICG was injected before ART and SLNs were identified, excised, and assessed intraoperatively using fast-frozen sections. Systemic pelvic lymphadenectomy was subsequently performed. The SLN detection rate, sensitivity, and false-negative rate were determined. Thirty patients desiring fertility preservation were enrolled, of whom 26 successfully completed ART and four underwent radical hysterectomies because of metastatic primary SLNs. Bilateral SLNs were identified in all patients. The sensitivity, false-negative rate, and negative predictive value were 100%, 7.7%, and 92.3%, respectively. Three (12%) patients were lost to follow-up: two relapsed and one died of tumor progression. Of the nine patients who tried to conceive after surgery, four achieved pregnancy and three delivered healthy live infants. In women with early-stage cervical cancer who desired to conserve fertility, SLN mapping with ICG had a very high detection rate, sensitivity, and low false-negative rate. SLN biopsy-guided ART is a feasible and accurate method for assessing pelvic node status.

British Gynaecological Cancer Society (BGCS) cervical cancer guidelines: Recommendations for practice

Cervix cancer in many countries is declining and screening programmes and immunisation will reduce the incidence in the next few decades. This guideline attempts to cover management of invasive disease reflecting diagnosis and imaging including new imaging and sentinel lymph node biopsies. Smaller volume disease is usually managed surgically whereas advanced disease is treated with (chemo)- radiation. It also includes discussion of fertility sparing procedures. Practices are changing frequently for all aspects of care usually in attempts to reduce complications and improve quality of life. The management of advanced disease is treated by chemotherapy and the use of newer agents is also discussed. Other sections discuss specialist situations such as cancer in pregnancy, rare cervical tumours, late effects and supportive measures and fertility preserving approaches.

Superparamagnetic iron oxide as a tracer for sentinel lymph node detection in uterine cancer: a pilot study

Sentinel lymph node (SLN) mapping using dye or radioisotopes has been performed in patients with uterine cancer. Superparamagnetic iron oxide (SPIO) can be handled safely and is taken up by lymph nodes (LNs); however, its efficacy in detecting SLNs in uterine cancer remains unknown. This pilot study evaluated the use of SPIO as a tracer for SLN detection in patients with uterine cancer. SPIO was injected into the uterine cervixes of 15 patients with uterine cancer scheduled for pelvic LN dissection. Magnetic resonance imaging (MRI) was performed preoperatively. Five patients also underwent radioisotope injection and single-photon emission computed tomography/computed tomography. Dissected LNs were stained with iron and examined pathologically. Of the radioisotope-positive LNs, 92% were also SPIO/MRI-positive. SPIO/MRI and iron staining were positively correlated. SLNs were identified by iron staining in 93% of cases. Iron staining was strongly positive in two of the five areas of LN metastasis; these were considered SLNs. Staining was negative or very weak in the other three areas and lymph flow disturbance was considered. SPIO and radioisotopes are taken up similarly by SLNs. SPIO/MRI and iron staining may thus be useful for detection of SLNs and diagnosis of LN metastasis in patients with uterine cancer.

The Risk of Para-Aortic Lymph Node Metastases in Apparent Early Stage Ovarian Cancer

Background and objectives: To identify the risk factors for para-aortic lymph node metastases in cases with presumed early stage ovarian cancer. Materials and methods: Between 2014 and 2019, 48 patients with apparent early stage ovarian cancer were submitted to surgery. In all cases, pelvic and para-aortic lymph node dissection was performed for staging purposes. Results: Among the 48 cases we identified nine cases with positive pelvic lymph nodes and 11 cases with positive para-aortic lymph nodes. The positivity of the retrieved lymph nodes was significantly correlated with the histopathological subtype represented by serous histology (p = 0.02), as well as with the degree of differentiation (p = 0.004). Conclusions: Patients with serous ovarian carcinomas in association with a poorer degree of differentiation are at risk of associated lymph node metastases even in presumed early stages of the disease. Therefore, lymph node dissection should be performed in such cases in order to provide adequate staging and tailoring of further treatment.

[Place of radiotherapy and surgery in the treatment of cervical cancer patients]

The treatment of cervical cancer patients relies on surgery and radiotherapy (according to the stage) and requires a multimodal discussion before any treatment to avoid adding the morbidities of each individual intervention and to optimize functional and oncological outcomes. The places of surgery and radiotherapy have been highlighted in recent international guidelines. For early stage tumors, an exclusive surgery with or without fertility sparing (according to well defined criteria) is the therapeutic standard. For tumors with risk factors (measuring more than 2cm in size and/or presence of lymphovascular invasion) a preoperative brachytherapy can be proposed to minimize the need for postoperative external beam radiotherapy and optimize local control. For locally advanced disease, the standard treatment relies on chemoradiation followed by a brachytherapy boost. A primary paraaortic lymph node dissection may guide radiotherapy volumes and is useful to identify patients requiring a para-aortic radiotherapy. The technical evolutions of surgical approaches and technological improvement of radiotherapy and brachytherapy should be analyzed in the context of prospective studies. We review the literature on the respective places of radiotherapy and surgery for the treatment of cervical cancer.

Selective biopsy of the sentinel node in cancer of cervix: Experience in validation phase

BACKGROUND AND OBJECTIVE

Sentinel lymph node biopsy (SLNB) was created to reduce the morbidity associated with pelvic lymphadenectomy in the early stages of cervical cancer (CC), preserving its prognostic information. The goal is to assess the diagnostic validity of SLNB in CC in initial stages (IA1 with lymphovascular infiltration (LVI) +, IA2, IB1 and IIA1), thus avoiding unnecessary lymphadenectomies in many of the cases.

MATERIAL AND METHOD

From January 2012 to April 2017, 23 patients with initial stages of CC were included in a cross-sectional study to evaluate the effectiveness of the SLNB in CC with a mixed technique of cervical injection of ^99mTc-nanocolloid of albumin and methylene blue, using combined planar lymphoscintigraphy with multimodality SPECT/CT image and subsequent removal of the sentinel node (SN) by laparoscopy.

RESULTS

The detection rate of SLNB with the mixed technique was 95.65%, with a negative predictive value (NPV) of 95.45% and sensitivity (S) of 100% in the case of bilateral drainage. The mean of excised SN was 3 (range 1-5). The bilateral detection rate in laparoscopy was 85.35%. The concordance between SPECT/CT and laparoscopy for the number and bilaterality of the SN using the Pearson coefficient was r = 0.727 and r = 0.833, respectively; p = 0.01. We only found one SN with a deferred result of micrometástasis and one false negative was detected.

CONCLUSIONS

SLNB in CC using a mixed technique has a high detection and bilateral drainage rate, but S is still low if we include cases of unilateral drainage. A greater number of cases and the development of intraoperative ultrastaging could increase the S of the technique and to reduce the number of false negatives.

Which is better for predicting pelvic lymph node metastases in patients with cervical cancer: Fluorodeoxyglucose-positron emission tomography/computed tomography or a sentinel node biopsy? A retrospective observational study

Systematic pelvic lymph node resection may not be needed for patients with cervical cancer, especially in the early stage, if the pre- or intraoperative diagnosis of lymph node status is correct. The aim of this study was to evaluate the diagnostic accuracy of pelvic lymph node metastasis for fluorodeoxyglucose-positron emission tomography/computed tomography (FDG PET/CT) and sentinel node biopsy (SNB) of cervical cancer patients.Forty-eight patients with cervical cancer were imaged with FDG PET/CT before radical hysterectomy and underwent an SNB followed by systematic pelvic lymph node dissection. The diagnostic accuracy for predicting pelvic node metastases for FDG PET/CT and SNB compared with the ultimate histologic status was analyzed.Among 96 hemi-pelvises (HPs) in 48 patients, pelvic lymph node metastases were obtained in 12 HPs. The sensitivity of pelvic node metastases for FDG PET/CT and SNB was 8.3% and 75.0%, respectively. The specificity for FDG PET/CT and SNB was 97.6% and 94.0%, respectively. The negative predictive value for FDG-PET/CT and SNB was 88.2% and 100%, respectively.SNB is more suitable for detecting pelvic node metastases than FDG PET/CT. The omission of systematic pelvic lymphadenectomy should be considered based on the findings of SNB, not FDG PET/CT.

Management of Para-aortic Lymph Node Disease in Patients With Cervical Cancer: What Is the Best Approach?

Cervical cancer remains a prevalent and deadly disease in low-income countries, especially among young and otherwise healthy women. Multimodality treatment has led to a significant improvement in outcomes for patients with locally advanced disease, and this is mainly because of the incorporation of platinum-based chemoradiotherapy in current treatment protocols. However, locally advanced tumors are associated with a greater risk for para-aortic lymph node (PALN) involvement, which is an important adverse prognostic factor. Most staging techniques have low accuracy for detection of disease in this area, which could lead to understaging and undertreatment. Meanwhile, patients with PALN disease are underrepresented in trials addressing the treatment of advanced cervical cancer and a few studies have been directed at this population. The aim of this review is to analyze the current data regarding staging and treatment of cervical cancer with PALN disease to determine which strategy is best when managing these patients.

Can We Define the Risk of Lymph Node Metastasis in Early-Stage Cervical Cancer Patients? A Large-Scale, Retrospective Study

BACKGROUND

Sentinel lymph node (SLN) biopsy has emerged as one of the most appreciated techniques for reducing the rate of complete lymph node dissection (LND) performed in patients with early-stage cervical cancer (ECC). However, its performances are still a matter of debate and, to improve them, international guidelines recommend performing at least unilateral LND in case of SLN mapping. In a prior study, we identified a group of patients without evidence of lymph node metastasis (LNM). Our objective is to define a precise risk of LNM for each ECC patient in order to significantly tailor surgery for ECC.

METHODS

Clinical and pathological data of ECC patients were retrospectively collected by eight Italian institutions. Chi-square test or Fisher's exact test along with logistic regression analysis was used to determine the association of each variable between patients with or without LNM. Results of logistic regression have been used as a basis to calculate the probability to harboring LNM.

RESULTS

A total of 463 ECC patients were identified. No LNM was detected among the 161 (34.8%) patients who met the criteria and were defined as Very Low Risk. In the other 302 patients, the precise risk of LNM was calculated, and it was <1% in 31 (10.3%) patients.

CONCLUSIONS

Defining the precise risk of LNM could lead to proper selection of patients in whom any lymph nodal procedure, including SLN, could be avoided.

The detection of sentinel lymph nodes in laparoscopic surgery for uterine cervical cancer using 99m-technetium-tin colloid, indocyanine green, and blue dye

OBJECTIVE

Our objective was to determine the feasibility and detection rates and clarify the most effective combination of injected tracer types for sentinel lymph node (SLN) mapping in uterine cervical cancer in patients who have undergone laparoscopic surgery or neoadjuvant chemotherapy (NAC).

METHODS

A total of 119 patients with cervical cancer underwent SLN biopsy at radical hysterectomy using three types of tracers. The various factors related to side-specific detection rate, sensitivity, and false negative (FN) rate were analyzed.

RESULTS

The SLN detection rates using 99m-technetium ((99m)Tc)-tin colloid, indigo carmine, and indocyanine green (ICG) were 85.8%, 20.2%, and 61.6%, respectively. The patients with ≥2-cm-diameter tumors and those who received NAC had lower detection rates than those with <2-cm-diameter tumors (75.7% vs. 91.5%, p<0.01) and those who did not receive NAC (67.9% vs. 86.3%, p<0.01), respectively. Laparoscopic procedures had a higher detection rate than laparotomy (100.0% vs. 77.1%, p<0.01). No factors significantly affected the sensitivity; however, the patients with ≥2-cm-diameter tumors (86.0% vs. 1.4%, p<0.01), NAC (19.4% vs. 2.2%, p<0.01), and those who underwent laparotomy (7.4% vs. 0%, p<0.01) had an unfavorable FN rate.

CONCLUSION

Among the examined tracers, (99m)Tc had the highest detection of SLN mapping in patients with uterine cervical cancer. Patients with local advanced cervical cancer with/without NAC treatment might be unsuited for SLN mapping. SLN mapping is feasible and results in an excellent detection rate in patients with <2-cm-diameter cervical cancer. Laparoscopic surgery is the best procedure for SLN detection in patients with early-stage disease.

Fertility-sparing surgery for uterine cervical cancer

The standard treatment for early cervical cancer of the uterus (CC) is radical hysterectomy with resection of the parametrium and pelvic lymphadenectomy. At least 40% of patients develop early-stage CC during child-bearing age, therefore preserving the uterus to maintain fertility has been an important consideration. Several surgical procedures including conization and vaginal or abdominal radical trachelectomy have been reported. These procedures are safe for removing lymph node negative CC tumors with <2 cm diameter. Recently, less radical surgical procedures that maintain fertility, such as conization, simple trachelectomy, minimally invasive surgery and neoadjuvant chemotherapy, have been indicated for tumors greater than 2 cm in diameter. In this review, we discuss the currently accepted surgical approaches for treating CC while maintaining fertility.

SEOM guidelines for cervical cancer

Cervical cancer (CC) is the second most common cancer worldwide, strongly linked to high-risk human papilloma virus infection. Although screening programs have led to a relevant reduction in the incidence and mortality due to CC in developed countries, it is still an important cause of mortality in undeveloped countries. Clinical stage is still the most relevant prognostic factor. In early stages, the primary treatment is surgery or radiotherapy, whereas concomitant chemo-radiotherapy is the conventional approach in locally advanced stages. In the setting of recurrent or metastatic CC, for the first time ever, the combination of chemotherapy plus bevacizumab prolongs the overall survival beyond 12 months. Therefore, this regimen is considered by most of the oncologist a new standard of care for metastatic/recurrent CC.