Clinical impact of low-volume lymph node metastases in early-stage cervical cancer: A comprehensive meta-analysis

Sentinel lymph node pathological ultrastaging: Final outcome of the Sentix prospective international study in patients with early-stage cervical cancer

OBJECTIVE

To report the outcome of SLN staging in the SENTIX international prospective trial of SLN biopsy in patients with cervical cancer with an intensive ultrastaging protocol and central quality control and to evaluate how the intensity of pathological assessment correlates with metastatic detection rate in SLNs.

METHODS

Eligible were patients with stages T1a1/LVSI+ to T1b2 (<4 cm, ≤2 cm for fertility sparing), common tumor types, no suspicious lymph nodes on imaging, and bilateral SLN detection. SLNs were examined intraoperatively and processed by an intensive protocol for ultrastaging (paraffin blocks sectioned completely in 150-μm intervals/levels). SLNs from each site were submitted for central quality control.

RESULTS

In the SENTIX SLN study, 647 out of 733 enrolled patients underwent SLN ultrastaging, identifying 12.5% (81/647) with node positive, N1 cases. Intraoperative detection revealed metastases in 56.8% (46/81) of these cases, categorized into macrometastases (83.7%), micrometastases (26.3%), and isolated tumor cells (9.1%). Ultrastaging identified additional metastatic involvement in 43.2% (35/81) of patients, with detailed sectioning revealing metastases (MAC/MIC) at first level in 20 cases (24.7%), at levels 2-4 in 9 cases (11.1%), and at level ≥5 in 6 cases (7.4%).

CONCLUSION

SLN ultrastaging detects additional 43% of N1 (MAC/MIC) in patients with negative LNs by imaging and intraoperative pathological assessment. The detection rate of positive SLN correlates with the intensity (number of levels) of ultrastaging. Examination of four levels from paraffin blocks, which detects >90% of patients with N1, is a reasonable compromise for an international standard for ultrastaging.

STUDY REGISTRATION

NCT02494063 (ClinicalTrials.gov).

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.

Value of sentinel node ultrastaging and pathologic techniques in tumoral detection

PURPOSE OF REVIEW

Sentinel lymph node assessment is an option for patients with clinically early-stage vulvar cancer, endometrial cancer, cervical cancer, and, more recently, ovarian cancer. However, although ultrastaging is mandatory as part of the node evaluation, universally accepted pathology protocols are lacking. This review focuses on the current evidence for the most relevant aspects of sentinel lymph node evaluation, as well as some controversial topics like frozen section or one-step nucleic acid amplification.

RECENT FINDINGS

The diagnostic accuracy of sentinel lymph node detection algorithms for patients with gynecologic neoplasms is high. However, the heterogeneity among the published studies and the absence of clear recommendations from most guidelines make it challenging to recommend one protocol over another. The minimum requirement from ultrastaging protocols (regarding the number of levels to be assessed, among others) to get the highest accuracy with a minor cost is unknown.

SUMMARY

Sentinel lymph node evaluation is now part of the surgical management for most early-stage gynecologic neoplasms. However, a universally accepted ultrastaging pathology protocol is lacking in literature and clinical practice. This gap requires significant effort from the gynecologic oncology and pathology community to be closed and then to allow advancements in surgical management for early-stage gynecologic tumors to go forward.

Tertiary prevention strategies for micrometastatic lymph node cervical cancer: A systematic review and a prototype of an adapted model of care

PURPOSE

We found a need for balancing the application of clinical guidelines and tailored approaches to follow-up of cervical cancer (CC) patients in the lymph node micrometastatic (MICs) setting. This review aimed to determine the current knowledge of management of MIC-positive CC cases.

METHODOLOGY

We addressed prognostic and risk of recurrence monitoring impacts associated with MIC+ cases. The electronic databases for literature and relevant articles were analysed.

RESULTS

Fifteen studies, (4882 patients), were included in our systematic review. While the results show that MICs significantly worsen prognosis in early CC. A tertiary prevention algorithm for low volume lymph node disease may stratify follow-up according to the burden of nodal disease and provide data that helps improve follow-up performance.

CONCLUSION

MICs worsen prognosis and should be managed as suggested by the algorithm. However, this algorithm must be externally validated. The clinical impact of isolated tumor cells (ITC) remains unclear.

Impact of PET/CT Imaging with FDG in Locally Advanced Cervical Carcinoma-A Literature Review

Positron emission tomography (PET) and computed tomography (CT) have evolved as a pivotal diagnostic modality in the field of oncology. With its increasing application in staging and ready availability, it becomes imperative for committed radiation oncologists to possess a complete analysis and understanding of integration of molecular imaging, which can be helpful for radiation planning, while also acknowledging its possible limitations and challenges. A significant obstacle lies in the synthesis and design of tumor-specific bmolecules for diagnosing and treating cancer. The utilization of radiation in medical biochemistry and biotechnology, encompassing diagnosis, therapy, and control of biological systems, is encapsulated under the umbrella term "nuclear medicine". Notably, the application of various radioisotopes in pharmaceutics has garnered significant attention, particularly in the realm of delivery systems for drugs, DNA, and imaging agents. The present article provides a comprehensive review of use of novel techniques PET and CT with major positron-emitting radiopharmaceuticals currently in progress or utilized in clinical practice with their integration into imaging and radiation therapy.

Comparative study using indocyanine green and patent blue dye for sentinel lymph node biopsy in patients with early-stage cervical cancer

BACKGROUND

Lymphatic involvement is the most important prognostic factor in early-stage cervical cancer. Sentinel lymph node biopsy is a viable alternative to systematic lymphadenectomy and may identify metastases more precisely.

OBJECTIVE

To compare two tracers (indocyanine green and patent blue) to detect sentinel nodes.

METHODS

A single-center, retrospective study of women treated due to early-stage cervical cancer (International Federation of Gynecology and Obstetrics 2009 IA1 with lymphovascular invasion, IA2, and IB1). Location and tracer of all detected sentinel nodes had been documented for a prospective, multicenter trial (SENTIX trial). All sentinel nodes were sent to frozen section and final analysis through ultrastaging using a standard protocol.

RESULTS

Overall, 103 patients were included. Bilateral detection rate for indocyanine green (93.2%) was significantly higher than for blue dye (77.7%; p=0.004). Their combined use significantly increased the bilateral detection to 99.0% (p=0.031). While 97.4% of all sentinel nodes were located below the common iliac vessels, no para-aortic nodes were labeled. Simultaneous bilateral detection with both tracers was found in 71.8% of the cases, of which the sentinel nodes were identical in 91.9%. Nine positive nodes were detected among seven patients (6.8%), all marked with indocyanine green while patent blue labeled six. Frozen section failed to detect one of three macrometastases and three of four micrometastases (sensitivity 43%; negative prediction value 96%).

CONCLUSION

Anatomical distribution and topographic localization of the sentinel nodes obtained with these tracers were not different. Indocyanine green provided a significantly higher bilateral detection rate and had superior sensitivity to detect positive nodes compared with patent blue. Combining indocyanine green and blue dye increased the bilateral detection rate significantly.

Survival associated with the use of one-step nucleic acid amplification (OSNA) to detect sentinel lymph node metastasis in cervical cancer

INTRODUCTION

Sentinel lymph node (SLN) biopsy is part of surgical treatment of apparent early-stage cervical cancer. SLN is routinely analyzed by ultrastaging and immunohistochemistry. The aim of this study was to assess the survival of patients undergoing SLN analyzed by one-step nucleic acid amplification (OSNA) compared with ultrastaging.

METHODS

Single-center, retrospective, cohort study. Patients undergoing primary surgery and SLN mapping ( ±pelvic lymphadenectomy) for apparent early-stage cervical cancer between May 2017 and January 2021 were included. SLN was analyzed exclusively with OSNA or with ultrastaging. Patients with bilateral SLN mapping failure, with SLN analyzed alternatively/serially with OSNA and ultrastaging, and undergoing neo-adjuvant therapy were excluded. Baseline clinic-pathological differences between the two groups were balanced with propensity-match analysis.

RESULTS

One-hundred and fifty-seven patients were included, 50 (31.8%) in the OSNA group and 107 (68.2%) in the ultrastaging group. Median follow up time was 41 months (95%CI:37.9-42.2). 5-year DFS in patients undergoing OSNA versus ultrastaging was 87.0% versus 91.0% (p = 0.809) and 5-year overall survival was 97.9% versus 98.6% (p = 0.631), respectively. No difference in the incidence of lymph node recurrence between the two groups was noted (OSNA 20.0% versus ultrastaging 18.2%, p = 0.931). In the group of negative SLN, no 5-year DFS difference was noted between the two groups (p = 0.692). No 5-year DFS and OS difference was noted after propensity-match analysis (87.6% versus 87.0%, p = 0.726 and 97.4% versus 97.9%, p = 0.998, respectively).

CONCLUSION

The use of OSNA as method to exclusively process SLN in cervical cancer was not associated with worse DFS compared to ultrastaging. Incidence of lymph node recurrence in the two groups was not different.

Precisional detection of lymph node metastasis using tFCM in colorectal cancer

The detection of colorectal cancer (CRC) lymph node (LN) metastases significantly influences treatment choices, yet identifying them in samples is time-consuming and error-prone. To enhance efficiency, we have established a LN metastasis detection method utilizing triple-parameter flow cytometry (tFCM) and have conducted a comparative assessment of its accuracy and cost-effectiveness in contrast to conventional pathological examinations. This technique utilized biomarkers cytokeratin 20 (CK20), epithelial cell adhesion molecules (EpCAM), and Pan-CK. tFCM's sensitivity was validated by analyzing known cell line concentrations (SW480 and SW620) in peripheral blood mononuclear cells (PBMCs), with CK20, EpCAM, and Pan-CK showing significant expression in CRC cell lines but not in PBMCs. A strong linear correlation was observed in the mixed leukocyte environment (R 2 = 0.9988). Subsequently, tFCM and pathological sections were employed to analyze LNs from CRC patients, enabling comparison of detection accuracy. Within the 36 LNs studied, tFCM successfully identified tumor cells with varying metastasis degrees, including micro-metastasis and isolated tumor cell clusters. Notably, relying solely on pathological sections led to a potential 25% misdiagnosis rate for LNs. In contrast, tFCM effectively minimized this risk. In summary, compared to traditional pathological sections, tFCM is a more advantageous method for detecting nodal metastasis in CRC patients, offering a more precise prognosis for these patients.

Survival after sentinel lymph node biopsy for early cervical cancers: a systematic review and meta-analysis

BACKGROUND

Sentinel lymph node biopsy represents an alternative to pelvic lymphadenectomy for lymph node staging of early-stage cervical carcinoma, but prospective evidence on long-term oncological safety of sentinel lymph node biopsy alone versus pelvic lymphadenectomy is missing.

OBJECTIVE

To investigate, with this meta-analysis, the impact of sentinel lymph node biopsy alone versus pelvic lymphadenectomy on survival for patients with early-stage cervical cancer.

METHODS

A systematic literature review was performed. We excluded studies in which pelvic lymphadenectomy was systematically performed after every sentinel lymph node biopsy, including only articles where pelvic lymphadenectomy was performed because sentinel lymph node biopsy was not conclusive. A meta-analysis was carried out combining 5-year disease-free survival and overall survival rates with a random and fixed effect model. Heterogeneity was tested using the Cochran Χ2 test and quantified with Higgins information I2.

RESULTS

The search of databases and registers found 927 items and six articles (two retrospective and four prospective). The median time of follow-up was 34.8 months (range 13-53). Overall common effect disease-free survival was 98% while random effect disease-free survival was 94%. Overall heterogeneity was 77%. A subgroup analysis was applied, dividing studies into one group including sentinel lymph node biopsy negative data only (common effect disease-free survival 91%; random effect disease-free survival 90%), and one group with a negative and positive sentinel lymph node biopsy (common effect disease-free survival 98%; random effect disease-free survival 96%). In the analysis of overall survival, positive and negative sentinel lymph node biopsy cases were examined together (common and random effect overall survival 99%). Ultrastaging did not affect disease-free survival (common and random effect disease-free survival 92% in the ultrastaging group vs common effect disease-free survival 99% and random effect disease-free survival 96% in the non-ultrastaging group).

CONCLUSIONS

Both 5-year disease-free survival and overall survival rate after sentinel lymph node biopsy alone are higher than 90% and do not differ from pelvic lymphadenectomy survival data. Ultrastaging did not impact survival.

MILACC study: could undetected lymph node micrometastases have impacted recurrence rate in the LACC trial?

OBJECTIVE

The etiology of inferior oncologic outcomes associated with minimally invasive surgery for early-stage cervical cancer remains unknown. Manipulation of lymph nodes with previously unrecognized low-volume disease might explain this finding. We re-analyzed lymph nodes by pathologic ultrastaging in node-negative patients who recurred in the LACC (Laparoscopic Approach to Cervical Cancer) trial.

METHODS

Included patients were drawn from the LACC trial database, had negative lymph nodes on routine pathologic evaluation, and recurred to the abdomen and/or pelvis. Patients without recurrence or without available lymph node tissue were excluded. Paraffin tissue blocks and slides from all lymph nodes removed by lymphadenectomy were re-analyzed per standard ultrastaging protocol aimed at the detection of micrometastases (>0.2 mm and ≤2 mm) and isolated tumor cells (clusters up to 0.2 mm or <200 cells).

RESULTS

The study included 20 patients with median age of 42 (range 30-68) years. Most patients were randomized to minimally invasive surgery (90%), had squamous cell carcinoma (65%), FIGO 2009 stage 1B1 (95%), grade 2 (60%) disease, had no adjuvant treatment (75%), and had a single site of recurrence (55%), most commonly at the vaginal cuff (45%). Only one patient had pelvic sidewall recurrence in the absence of other disease sites. The median number of lymph nodes analyzed per patient was 18.5 (range 4-32) for a total of 412 lymph nodes. A total of 621 series and 1242 slides were reviewed centrally by the ultrastaging protocol. No metastatic disease of any size was found in any lymph node.

CONCLUSIONS

There were no lymph node low-volume metastases among patients with initially negative lymph nodes who recurred in the LACC trial. Therefore, it is unlikely that manipulation of lymph nodes containing clinically undetected metastases is the underlying cause of the higher local recurrence risk in the minimally invasive arm of the LACC trial.

Prognostic value of 18F-FDG PET in uterine cervical cancer patients with stage IIICr allocated by imaging

The effect on survival of radiographic lymph node metastasis in uterine cervical cancer patients is more important than before, even though its prognostic value not been well investigated. The aim of our study is to evaluate the prognostic potential of 18F-fluorodeoxyglucose Positron Emission Tomography (18F-FDG PET) compared with Computed Tomography (CT) in uterine cervical cancer patients with stage IIICr allocated by imaging. Fifty-five patients with biopsy-proven primary cervical cancer underwent definitive radiation therapy for stages IIB-IVB of The International Federation of Gynecology and Obstetrics (FIGO) 2018 classifications. The prognostic performance of pretreatment 18F-FDG PET and CT for assessing lymph node metastasis was evaluated by two experienced readers. The PET and CT findings were correlated with the risk of progression-free survival (PFS) and overall survival (OS). Kaplan-Meier survival curves showed that PFS was significantly worse in patients with positive lymph nodes on 18F-FDG PET than in those patients with negative lymph nodes on 18F-FDG PET (p = 0.003), whereas there was no significant difference in PFS between patients with lymph nodes sized ≥ 1 cm and those sized < 1 cm (p = 0.140). Univariate analysis showed that positive lymph nodes on 18F-FDG PET was significantly associated with poor PFS (p = 0.006), whereas lymph node size was not significantly associated with poor PFS (p = 0.145). In multivariate analysis, positive lymph nodes on 18F-FDG PET was significantly associated with poor PFS (p = 0.006) and was an independent prognostic factor for PFS. 18F-FDG PET offers high prognostic value for patients with stage IIICr allocated by imaging compared with CT, suggesting that 18F-FDG PET might be useful in clinical staging decisions and thus promote optimal diagnostic and therapeutic strategies.

Predictors of Non-Sentinel Lymph Node Metastasis in Patients with Positive Sentinel Lymph Node in Early-Stage Cervical Cancer: A SENTICOL GROUP Study

BACKGROUND

The goal of this study was to identify the risk factors for metastasis in the remaining non-sentinel lymph nodes (SLN) in the case of positive SLN in early-stage cervical cancer.

METHODS

An ancillary analysis of two prospective multicentric databases on SLN biopsy for cervical cancer (SENTICOL I and II) was performed. Patients with early-stage cervical cancer (FIGO 2018 IA to IIA1), with bilateral SLN detection and at least one positive SLN after ultrastaging, were included.

RESULTS

405 patients were included in SENTICOL I and Il. Fifty-two patients had bilateral SLN detection and were found to have SLN metastasis. After pelvic lymphadenectomy, metastatic involvement of non-SLN was diagnosed in 7 patients (13.5%). Patients with metastatic non-SLN were older (51.9 vs. 40.8 years, p = 0.01), had more often lympho-vascular space invasion (LVSI) (85.7% vs. 35.6%, p = 0.03), and had more often parametrial involvement (42.9% vs. 6.7%, p = 0.003). Multivariate analysis retained age (OR = 1.16, 95% IC = [1.01-1.32], p = 0.03) and LVSI (OR = 25.97, 95% IC = [1.16-582.1], p = 0.04) as independently associated with non-SLN involvement.

CONCLUSIONS

Age and LVSI seemed to be predictive of non-SLN metastasis in patients with SLN metastasis in early-stage cervical cancer. Larger cohorts are needed to confirm the results and clinical usefulness of such findings.

Finding the sentinel lymph node in early cervical cancer: When is unusual not uncommon?

OBJECTIVE

To report our institutional experience with sentinel lymph node (SLN) detection using indocyanine green for cervical cancer, in terms of detection rates, detection of SLN at unusual locations, and factors associated with unusual SLN locations. In addition, we performed a systematic review of the literature to identify factors associated with unusual SLN localizations.

METHODS

This is a retrospective cohort study of women with early-stage cervical cancer undergoing sentinel lymph node mapping between 2015 and 2019. Outcome measures were SLN detection rates, detection rates of unusual locations for SLN and risk factors for aberrant lymphatic drainage pathways. In addition, studies evaluating factors associated with unusual SLN locations in cervical cancer were assessed in a systematic review.

RESULTS

A total of 100 patients were included. The unilateral SLN detection rate was 88%, whereas the bilateral detection rate was 75%. In 37% of all patients, SLN were found in unusual locations, and in 10% of patients SLN were solely found in unusual locations. Body mass index (BMI) was associated with finding SLN in unusual locations, with unusual nodes detected in 52% of patients with BMI <25 kg/m² and in 28% of patients with BMI ≥25 kg/m². The systematic review identified three studies, identifying lower BMI, nulliparity and tumor size of >20 mm as factors associated with finding SLN at unusual locations.

CONCLUSION

Aberrant drainage sites represent a significant proportion of SLN detected in cervical cancer. Factors associated with increased rates of unusual nodal locations are a lower BMI, with a possible association with nulliparity and tumor size of >20 mm.

Recent Advances in Cervical Cancer Management: A Review on Novel Prognostic Factors in Primary and Recurrent Tumors

BACKGROUND

Several pathological parameters, including tumor size, depth of stromal invasion, lympho-vascular space invasion and lymph node status, have been proposed as prognostic predictors in cervical cancer. However, given the high mortality and recurrence rate of cervical cancer, novel parameters that are able to provide additional prognostic information are needed in order to allow a better prognostic stratification of cervical cancer patients.

METHODS

A search was conducted on PubMed to identify relevant literature data regarding prognostic factors in cervical cancer. The key words "cervical cancer", "prognostic factors", "pathology", and "outcome" were used.

RESULTS

The novel pathological grading system based on tumor budding and cell nest size appeared the most relevant prognostic factor in primary neoplasms. Moreover, other potentially useful prognostic factors were tumor size, depth of stromal invasion, lympho-vascular space invasion, perineural invasion, tumor-free distance and tumor-infiltrating lymphocytes. Prognostic factors related to advanced-stage cervical cancer, including lymph-nodes status, endometrial and cervical involvement as well as distant metastases, were also taken into consideration.

CONCLUSIONS

According to our findings, tumor budding and cell nest size grading system, depth of stromal invasion, lympho-vascular space invasion, perineural invasion, tumor-free distance and tumor-infiltrating lymphocytes appeared the most relevant factors included in the pathology report.

Stratification of lymph node metastases as macrometastases, micrometastases, or isolated tumor cells has no clinical implication in patients with cervical cancer: Subgroup analysis of the SCCAN project

BACKGROUND

In cervical cancer, presence of lymph-node macrometastases (MAC) is a major prognostic factor and an indication for adjuvant treatment. However, since clinical impact of micrometastases (MIC) and isolated tumor-cells (ITC) remains controversial, we sought to identify a cut-off value for the metastasis size not associated with negative prognosis.

METHODS

We analyzed data from 967 cervical cancer patients (T1a1L1-T2b) registered in the SCCAN (Surveillance in Cervical CANcer) database, who underwent primary surgical treatment, including sentinel lymph-node (SLN) biopsy with pathological ultrastaging. The size of SLN metastasis was considered a continuous variable and multiple testing was performed for cut-off values of 0.01-1.0 mm. Disease-free survival (DFS) was compared between N0 and subgroups of N1 patients defined by cut-off ranges.

RESULTS

LN metastases were found in 172 (18%) patients, classified as MAC, MIC, and ITC in 79, 54, and 39 patients, respectively. DFS was shorter in patients with MAC (HR 2.20, P = 0.003) and MIC (HR 2.87, P < 0.001), while not differing between MAC/MIC (P = 0.484). DFS in the ITC subgroup was neither different from N0 (P = 0.127) nor from MIC/MAC subgroups (P = 0.449). Cut-off analysis revealed significantly shorter DFS compared to N0 in all subgroups with metastases ≥0.4 mm (HR 2.311, P = 0.04). The significance of metastases <0.4 mm could not be assessed due to limited statistical power (<80%). We did not identify any cut-off for the size of metastasis with significantly better prognosis than the rest of N1 group.

CONCLUSIONS

In cervical cancer patients, the presence of LN metastases ≥0.4 mm was associated with a significant negative impact on DFS and no cut-off value for the size of metastasis with better prognosis than N1 was found. Traditional metastasis stratification based on size has no clinical implication.

Development and validation of a nomogram for predicting pelvic lymph node metastasis and prognosis in patients with cervical cancer

Objective

Cervical cancer (CC) is one of the main causes of death among gynecological malignancies. Patients with CC with lymph node metastasis (LNM) have poor prognoses. We investigated the risk factors and prognosis of LNM in patients with CC patients using data from the SEER database.

Methods

We collected the information of cervical cancer patients registered in SEER database from 2010 to 2015. The dataset was divided into a training set and a validation set at a 7:3 ratio. LASSO regression analysis was used to evaluate risk factors for LNM in patients with CC. Using the results, we established a nomogram prediction model. C-index, ROC curves, calibration curves, decision curve analysis, and clinical impact curves were used to evaluate the prediction performance of the model.

Results

We included 14,356 patients with CC in the analysis. Among these, 3997 patients were diagnosed with LNM. A training set (10,050 cases) and a validation set (4306 cases) were used for the following analysis. We established nomogram LNM prediction models for the patients with T_1-2-stage CC. The C-indices for the internal and external validations of the prediction models were 0.758 and 0.744, respectively. In addition, we established a prognostic nomogram for all CC patients with LNM, and the internal and external validation C-indices were 0.763 and 0.737.

Conclusion

We constructed a quantitative and visual predictive nomogram that predicted prognosis of patients with LNM in CC to provide clinicians with a reference for diagnosis and treatment.