Influence of lymphadenectomy on survival and recurrence in patients with early-stage epithelial ovarian cancer: a meta-analysis

BACKGROUND

This meta-analysis aimed to evaluate the effectiveness of lymphadenectomy on survival and recurrence in patients with early-stage epithelial ovarian cancer (eEOC).

METHODS

Relevant studies were searched from four online databases. Hazard ratios (HRs) with 95% confidence intervals (CIs) or risk ratios (RRs) with 95% CIs were used to evaluate the effects of lymphadenectomy on overall survival (OS), progression-free survival (PFS), and recurrence rates. A subgroup analysis was performed to explore the sources of heterogeneity, followed by sensitivity and publication bias assessments.

RESULTS

Fourteen articles involving 22,178 subjects were included. Meta-analysis revealed that lymphadenectomy was significantly associated with improved OS (HR = 0.72; 95% CI:0.61, 0.84; P < 0.001), improved PFS (HR = 0.74; 95% CI: 0.67, 0.80; P < 0.001), and reduced recurrence rates (RR = 0.72; 95% CI: 0.60, 0.85; P < 0.001). Subgroup analysis showed that factors including area, histology, and source of the control group were significantly related to improved OS and PFS in patients with eEOC. Sensitivity analysis showed that the combined results were stable and reliable, and no significant publication bias was observed.

CONCLUSIONS

Patients with eEOC can benefit from lymphadenectomy, with improved survival outcomes (OS and PFS) and a lower recurrence rate.

Multiparametric Dual-Time-Point [18F]FDG PET/MRI for Lymph Node Staging in Patients with Untreated FIGO I/II Cervical Carcinoma

[¹⁸F]FDG PET/MRI was shown to have limited sensitivity for N-staging in FIGO I/II cervical carcinoma. Therefore, this prospective study aimed to investigate the additional value of multiparametric dual-time-point PET/MRI and to assess potential influencing factors for lymph node metastasis (LNM) detection. A total of 63 patients underwent whole-body dual-time-point [¹⁸F]FDG PET/MRI 60 + 90 min p.i., and 251 LN were evaluated visually, quantified multiparametrically, and correlated with histology. Grading of the primary tumor (G2/G3) had a significant impact on visual detection (sens: 8.3%/31%). The best single parameter for LNM detection was SUVavg, however, with a significant loss of discriminatory power in G2 vs. G3 tumors (AUC: 0.673/0.901). The independent predictors SUVavg, ∆SUVpeak, LN sphericity, ADC, and histologic grade were included in the logistic-regression-based malignancy score (MS) for multiparametric analysis. Application of MS enhanced AUCs, especially in G2 tumors (AUC: G2:0.769; G3:0.877) and improved the accuracy for single LNM from 34.5% to 55.5% compared with the best univariate parameter SUVavg. Compared with visual analysis, the use of the malignancy score increased the overall sensitivity from 31.0% to 79.3% (Youden optimum) with a moderate decrease in specificity from 98.3% to 75.6%. These findings indicate that multiparametric evaluation of dual-time-point PET/MRI has the potential to improve accuracy compared with visual interpretation and enables sufficient N-staging also in G2 cervical carcinoma.

Clinical issues of surgery for uterine endometrial cancer in Japan

OBJECTIVE

The mainstay of treatment for uterine endometrial cancer is surgery, and recurrent-risk cases require multidisciplinary treatment, including surgery, chemotherapy and radiation therapy.

METHODS

The standard surgery for uterine endometrial cancer is hysterectomy and bilateral salpingooophorectomy, with additional retroperitoneal lymph node dissection and omentectomy, depending on the case. The appropriate treatment is determined based on the risk classification, such as the depth of invasion into the myometrium, diagnosis of histological type and grade, and risk assessment of lymph node metastasis.

RESULTS

Recently, minimally invasive surgery has been widely used not only in low-risk patients but also in intermediate- and high-risk patients. In low-risk patients, the possibility of ovarian preservation is discussed from a healthcare perspective for young women. Determining the need for retroperitoneal lymph node dissection based on sentinel lymph node evaluation may contribute in minimizing the incidence of post-operative lymphedema while ensuring accurate diagnosis of lymph node metastasis. Recently, many studies using sentinel lymph nodes have been reported for patients with uterine endometrial cancer, and the feasibility of sentinel lymph node mapping surgery has been proven. Unfortunately, sentinel lymph node biopsy and sentinel lymph node mapping surgery have not been widely adopted in surgery for uterine cancer in Japan. In addition, the search for biomarkers, such as RNA sequencing using The Cancer Genome Atlas, metabolic profile and lipidomic profile for early detection and prognostic evaluation, has been actively pursued.

CONCLUSIONS

Gynecologic oncologists expect to be able to provide uterine endometrial cancer patients with appropriate treatment that preserves their quality of life without compromising oncologic outcomes in the near future.

PET-CT versus MRI in the diagnosis of lymph node metastasis of cervical cancer: A meta-analysis

To compare the clinical application value of positron emission tomography-computed tomography (PET-CT) and magnetic resonance imaging (MRI) in the diagnosis of cervical cancer lymph node metastasis. We searched PubMed and other databases for the studies comparing the use of PET-CT and MRI for the diagnosis of cervical cancer lymph node metastasis up to January 20, 2021. We strictly followed the inclusion and exclusion criteria to screen the literature and extract the data. Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool was used for quality evaluation of included studies, and Revman 5.3 and Stata 15.0 software were used for evaluating heterogeneity, synthesize sensitivity (SEN), specificity (SPE), positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and the area under the curve (AUC) and comparing the pretest and posttest probabilities. Finally, 11 studies were included for meta-analysis. The synthesized results indicated that the SEN value of PET-CT was 0.65 (0.60 ~ 0.69) and SPE was 0.93 (0.91 ~ 0.94), and the SEN value of MRI was 0.58 (0.54 ~ 0.63) and SPE was 0.91 (0.90 ~ 0.92). AUC of PET-CT was 0.824, which was significantly higher than that of MRI (AUC = 0.702; p < .05). The subgroup analysis showed that the AUC value of the study based on study design and use of blinding methods was not statistically significant (all p > .05). There was no obvious publication bias in the synthesized analysis of the diagnostic value of PET-CT and MRI (all p > .05). HIGHLIGHTS: To compare positron emission tomography-computed tomography (PET-CT) and magnetic resonance imaging (MRI) in diagnosis of cervical cancer lymph node metastasis. Synthesize sensitivity value of PET-CT was comparable with that of MRI. Area under the curve of PET-CT was significantly higher than that of MRI. There was no obvious publication bias in synthesized analysis.

Establishment of a Diagnostic Method for Pelvic Sentinel Lymph Node Metastasis by Contrast-Enhanced Ultrasound in Uterine Cancer

This study investigated the usefulness of conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) in distinguishing metastasis of pelvic sentinel lymph nodes (SLNs) in patients with gynecological cancer. We examined 74 SLNs of patients with endometrial cancer (n = 26) and cervical cancer (n = 11). Patients underwent US and CEUS followed by SLN biopsy; US and CEUS results were evaluated visually and quantitatively and compared between pathological metastasis-negative and -positive groups. To support CEUS results, the microvessel density of SLNs was evaluated immunohistochemically. Seventeen positive and 40 negative SLNs were evaluable. Margin and enhancement patterns by visual assessment revealed significant differences (p = 0.046 and 0.022, respectively). In quantitative time-intensity curve analyses, the weakest peak intensities (PI_min), PI ratio and PI difference indicated significant differences (p = 0.045, p < 0.001 and p < 0.001, respectively). The areas under the receiver operating characteristic curves (AUCs) were 0.64, 0.82 and 0.83, respectively. The most effective PI ratio from the AUC was 1.3 (sensitivity = 82%, specificity = 70%), and the PI difference from the AUC was 20 (sensitivity = 88%, specificity = 70%). Microvessel density was significantly lower in metastatic lesions than in other areas. The quantitative analysis of CEUS seemed to be a reasonable method for distinguishing lymph node metastasis in patients with gynecological cancer.

Sentinel node mapping vs. sentinel node mapping plus back-up lymphadenectomy in high-risk endometrial cancer patients: Results from a multi-institutional study

OBJECTIVE

Sentinel node mapping (SLN) has replaced lymphadenectomy for staging surgery in apparent early-stage low and intermediate risk endometrial cancer (EC). Only limited data about the adoption of SNM in high risk EC is still available. Here, we evaluate the outcomes of high-risk EC undergoing SNM (with or without back-up lymphadenectomy).

METHODS

This is a multi-institutional international retrospective study, evaluating data of high-risk (FIGO grade 3 endometrioid EC with myometrial invasion >50% and non-endometrioid histology) EC patients undergoing SNM followed by back-up lymphadenectomy and SNM alone.

RESULTS

Chart of consecutive 196 patients were evaluated. The study population included 83 and 113 patients with endometrioid and non-endometrioid EC, respectively. SNM alone and SNM followed by back-up lymphadenectomy were performed in 50 and 146 patients, respectively. Among patients having SNM alone, 14 (28%) were diagnosed with nodal disease. In the group of patients undergoing SNM plus back-up lymphadenectomy 34 (23.2%) were diagnosed with nodal disease via SNM. Back-up lymphadenectomy identified 2 (1%) additional patients with nodal disease (in the para-aortic area). Back-up lymphadenectomy allowed to remove adjunctive positive nodes in 16 (11%) patients. After the adoption of propensity-matched algorithm, we observed that patients undergoing SNM plus back-up lymphadenectomy experienced similar disease-free survival (p = 0.416, log-rank test) and overall survival (p = 0.940, log-rank test) than patients undergoing SLN alone.

CONCLUSIONS

Although the small sample size, and the retrospective study design this study highlighted that type of nodal assessment did not impact survival outcomes in high-risk EC. Theoretically, back-up lymphadenectomy would be useful in improving the removal of positive nodes, but its therapeutic value remains controversial. Further prospective evidence is needed.

Lymphedema and Post-Operative Complications after Sentinel Lymph Node Biopsy versus Lymphadenectomy in Endometrial Carcinomas-A Systematic Review and Meta-Analysis

Background: Lymph node dissection (LND) is recommended as staging procedure in presumed low stage endometrial cancer. LND is associated with risk of lower-extremity lymphedema and post-operative complications. The sentinel lymph node (SLN) procedure has been shown to have high diagnostic accuracy, but its effects on complication risk has been little studied. This systematic review compares the risk of lower-extremity lymphedema and post-operative complications in SLN versus LND in patients with endometrial carcinoma. Methods: A systematic search was conducted in PubMed and Cochrane Library. Results: Seven retrospective and prospective studies (total n = 3046 patients) were included. Only three studies reported the odds ratio of lower-extremity lymphedema after SLN compared to LND, which was 0.05 (95% CI 0.01-0.37; p = 0.067), 0.07 (95% CI 0.00-1.21; p = 0.007) and 0.54 (95% CI 0.37-0.80; p = 0.002) in these studies. The pooled odds ratio of any post-operative complications after SLN versus LND was 0.52 (95% CI 0.36-0.73; I² = 48%; p < 0.001). For severe post-operative complications the pooled odds ratio was 0.52 (95% CI 0.28-0.96; I² = 0%; p = 0.04). Conclusions: There are strong indications that SLN results in a lower incidence of lower-extremity lymphedema and less often severe post-operative complications compared to LND. In spite of the paucity and heterogeneity of studies, direction of results was similar in all studies, supporting the aforementioned conclusion. These results support the increasing uptake of SLN procedures in endometrial cancer.

Status of Sentinel Lymph Node Biopsy in Vulvar and Cervical Cancer

Assessment of lymphatic metastasis is an essential component of solid tumour staging. Sentinel lymph node (SLN) biopsy is a minimally invasive procedure that allows regional lymph node involvement by tumour to be estimated by selectively examining the sentinel lymph node while minimising the morbidity of systematic lymph node dissection. Within the group of genital cancers, the diagnostic value of SLN biopsy is rated differently. For selected patients with early-stage vulvar cancer (unifocal primary tumour < 4 cm, clinically negative inguinal lymph nodes) the SLN technique is already an established procedure in the guidelines of the German Society for Gynaecology and Obstetrics (DGGG)/German Cancer Society (DKG) and the recommendations of the European Society of Gynaecological Oncology (ESGO). For cervical cancer, SLN biopsy has not yet been sufficiently standardised but can be considered for patients without risk factors with a primary tumour size < 2 cm. The SLN is identified by combined use of radioactive ^99m technetium nanocolloid and patent blue. The use of indocyanine green offers an alternative for SLN identification with few side effects. Recent studies aim to increase the diagnostic reliability of intraoperative frozen section analysis as this continues to show limited sensitivity in both vulvar and cervical cancer. The rate of detection of micrometastases can be increased by additional ultrastaging, the prognostic significance of which for both diseases is still unclear. The prognostic value of SLN biopsy compared with systematic lymph node dissection is being investigated in current studies (GROINSS-V-II for vulvar cancer and SENTIX-, SENTICOL-3 for cervical cancer). For this review article, a guideline-based literature search was performed in the National Library of Medicine (PubMed/MEDLINE) database with a particular focus on recent cohort studies and conference contributions.

Diagnostic criteria of sentinel lymph node micrometastasis or macrometastasis based on tissue rinse liquid-based cytology in gynecological cancer

OBJECTIVE

This study aimed to establish intraoperative diagnostic criteria of sentinel lymph node (SLN) micro-/macrometastasis on the basis of tissue rinse liquid-based cytology (TRLBC) in gynecological cancer.

METHODS

We enrolled 214 patients with gynecological cancer who underwent rapid diagnosis of SLN metastasis on the basis of TRLBC from a total of 490 SLNs. For slides that were classified as positive for atypical cells on cytological inspection, we counted the number of clusters (an atypical cell mass consisted of three or more cells) and the number of single cells (an atypical cell other than clusters). Receiver operating characteristic (ROC) analysis was applied to determine the efficiency of predicting SLN micro-/macrometastasis.

RESULTS

On cytological inspection, 36 slides were classified as positive for atypical cells, while 21 slides (4.3%) were true positive, 15 (3.1%) were false positive, and 454 (92.6%) were true negative. There were no false negative results in this study. The area under the ROC curve for the number of cluster was superior to that for the number of single cells for distinguishing micro-/macrometastasis from negative/isolated tumor cells (0.86 vs. 0.67, P = 0.032). The optimum cut-off value of the number of clusters was 5 for distinguishing these two categories.

CONCLUSIONS

TRLBC is a highly sensitive alternative for detecting SLN metastasis as a rapid intraoperative diagnosis. Counting the number of atypical cell clusters might be useful for distinguishing micro-/macrometastasis from isolated tumor cells.