The prognostic impact of the ratio of positive lymph nodes on survival of epithelial ovarian cancer patients

How Many Nodes to Take? Lymph Node Ratio Below 1/3 Reduces Papillary Thyroid Cancer Nodal Recurrence

INTRODUCTION

Papillary thyroid carcinoma (PTC) accounts for the majority of thyroid malignancies; risk of PTC recurrence over a 30-year period is approximately 30%, of which 70% occur as nodal metastases. Patients with nodal disease who are treated with therapeutic dissection are at higher risk for recurrence, but optimal nodal yield has not been defined. We aim to determine variables predictive of nodal recurrence of PTC within the first 5 years of surgery, with a focus on lymph node ratio (LNR), to inform clinical decision-making.

METHODS

Retrospective chart review identified 41 patients with nodal recurrence of PTC and 284 without nodal recurrence following thyroid surgery from 2000 to 2015. Cohorts were compared with regards to clinical history, surgical findings, and tumor characteristics.

RESULTS

The fraction of the patients who underwent therapeutic central or lateral lymph node dissection was significantly higher in the nodal recurrence cohort. Maximum tumor size, presence of extrathyroidal extension, largest lymph node focus, LNR, postoperative thyroglobulin level, and administration of postoperative radioactive iodine were significantly increased in the PTC nodal recurrence group. LNR greater than 0.3 held the highest level of significance as a binary cutoff and captured the larger proportion of patients in the nodal recurrence cohort (68.3%).

CONCLUSION

This study demonstrates characteristics to help assess risk of nodal recurrence of PTC and suggests LNR of lower than 0.3 is optimal to reduce risk of recurrence. The next steps include cohort studies to validate findings and weight variable analysis to optimize the extent of surgical therapeutic dissection.

LEVEL OF EVIDENCE

4 Laryngoscope, 132:1883-1887, 2022.

The association between lymph node metastases and long-term survival in patients with epithelial ovarian cancer

INTRODUCTION

A key survival prognosis factor for patients treated for ovarian cancer is complete cytoreductive surgery where all macroscopic neoplastic implants, including enlarged metastatic lymph nodes, are removed. We presume that investigating the involvement of the lymphatic system can result in a more individualized approach to the treatment of ovarian cancer patients. The main aim of our study was to analyze the relationship between the presence, number and types of lymph node metastases and ovarian cancer patient prognosis.

MATERIAL AND METHODS

We carried out a retrospective analysis of patients who underwent cytoreduction due to primary ovarian cancer, between 2010 and 2015. We analyzed the number of metastatic lymph nodes, the lymph node ratio defined as the ratio of the number of metastatic lymph nodes to the total number of lymph nodes removed, extracapsular involvement, and the histopathological pattern of metastases.

RESULTS

The study group included 651 patients. Of these, 377 had lymphadenectomy, 144 presented with lymph node metastases, and 233 had no lymph node metastases. We also included a group of 274 patients who did not have lymphadenectomy. Patients with more than 4 metastatic lymph nodes and a lymph node ratio of ≥ 0.1 had significantly poorer overall survival. Extracapsular involvement had no relation to patient overall survival. Multivariant survival analysis indicated that a lymph node ratio of ≥ 0.1 was an independent predictor of poor survival.

CONCLUSIONS

The analysis of lymph node metastases in ovarian cancer patients can have predictive value for patient overall survival.

Survival Analysis of Lymph Node Resection in Ovarian Cancer: A Population-Based Study

Objective: This study aimed at comprehensively investigating the survival impact of lymphadenectomy during primary surgery in ovarian cancer. Methods: Based on the surveillance, epidemiology, and end results registry (SEER) database, we included ovarian cancer patients with detailed information between 2010 and 2016. Cox regression was performed to select prognostic factors. We conducted propensity score-weighted survival analysis to balance baseline variables, and series of stratified analyses to control main confounding factors. Results: A total of 8,652 patients were ultimately identified. Among 4,360 patients with advanced disease, lymphadenectomy did not show significant survival benefit in general (median overall survival 44 months in non-lymphadenectomy vs. 49 months in lymphadenectomy group, P = 0.055). In subgroup analysis on patients received optimal debulking, lymphadenectomy did not significantly benefit the survival outcome (median overall survival 51, 47, 60, and 58 months in the non-lymphadenectomy, 1-9 lymph nodes, 10-19 lymph nodes, ≥20 lymph nodes groups, respectively, P = 0.287). Consistent results were observed in further stratification analyses. In optimal debulking subgroup, lymph node metastasis indicated worse survival. However, when limited the number of removed lymph nodes to more than 15, there was a marginal statistical difference in overall survival (P = 0.0498) while no significant difference presented in cause-specific survival (P = 0.129) between non-lymphadenectomy, pathological negative lymph node group and positive lymph node group. And the regions of lymph metastasis were also not significantly associate with survival (P = 0.123). Among 3,266 (75%) patients with apparent early-stage disease received lymphadenectomy, 7.75% of whom were reported isolated lymph nodes metastasis and have a poorer survival (P < 0.05). Conclusions: In primary debulking for patients with advanced ovarian cancer, lymphadenectomy was not associated with more favorable outcomes when compared to no lymphadenectomy. The value of lymphadenectomy lies more in staging for apparent early disease rather than therapeutic benefit.

Prognostic value of lymph nodes ratio in patients with stage III ovarian clear cell carcinoma: A retrospective study of patients in Southwest China

Background: Ovarian clear cell carcinoma (OCCC) has a worse prognosis compared to other histological subtypes. Although the survival effect of lymph nodes ratio (LNR) on ovarian carcinoma have been elucidated in several studies, the prognostic effect of LNR in OCCC has not been separately studied. This study aimed to investigate the prognostic significance of LNR in FIGO stage III OCCC.

Methods: Patients with FIGO stage III OCCC who underwent primary cytoreductive surgery and systematic lymphadenectomy from January 2008 to June 2014 in two independent hospitals were retrospectively reviewed. Two independent patients cohorts were used to investigate the survival impact of LNR by using Kaplan-Meier and Cox regression proportional hazard method.

Results: In training cohort, the 5-year progression-free survival (PFS) rates was 32.4% for patients with LNR ≤ 25%, and 19.8% for patients with LNR > 25%, respectively (p = 0.017). The 5-year overall survival (OS) rates was 41.3% for patients with LNR ≤ 25%, and 25.8% for patients with LNR > 25%, respectively (p = 0.003). In multivariate analysis, increased LNR was correlated with a poorer DFS (HR = 2.12 ,95% CI 1.32-3.41, p = 0.002) and OS (HR = 2.29, 95% CI 1.37-5.12, p = 0.001). These results were verified in a validation cohort.

Conclusions: LNR is an independent survival predictor in patients with FIGO stage III OCCC.

Survival effect of different lymph node staging methods on ovarian cancer: An analysis of 10 878 patients

Background

To compare the survival impact of several lymph node staging methods and therapeutic role of lymphadenectomy in patients with epithelial ovarian cancer who had undergone lymphadenectomy.

Methods

Data were retrospectively collected from the Surveillance, Epidemiology, and End Results program between 1988 and 2013.

Results

An increasing number of resected lymph nodes (RLNs) was associated with a significant improvement in survival of FIGO stage II and III disease. However, for FIGO stage IV patients, better survival was not significantly associated with a more extensive lymphadenectomy. A higher lymph node ratio (LNR) and log odds of positive lymph nodes (LODDS) were associated with poorer survival regardless of stage. Nevertheless, four‐category classification of LODDS was more suitable for stage IV patients when three‐category classification was compatible with stage I‐III disease. Multivariate analysis demonstrated that LODDS and LNR were significant independent prognostic factors, but not RLN classification.

Conclusion

Sixteen to thirty RLNs are recommended for stage I disease. For stages II and III patients, the more lymph node excision, the better the prognosis. However, lymphadenectomy was nonessential for stage IV patients. Considering staging methods, for stages II and III patients, three‐category classification of LODDS was recommended to evaluate the prognosis. For stage I and IV, three‐category classification of positive LNR was idoneous.

Impact of lymph node ratio on survival in stage III ovarian high-grade serous cancer: a Turkish Gynecologic Oncology Group study

Objective

The purpose of this study was to investigate the prognostic value of lymph node ratio (LNR) in patients with stage III ovarian high-grade serous carcinoma (HGSC).

Methods

A multicenter, retrospective department database review was performed to identify patients with ovarian HGSC at 6 gynecologic oncology centers in Turkey. A total of 229 node-positive women with stage III ovarian HGSC who had undergone maximal or optimal cytoreductive surgery plus systematic lymphadenectomy followed by paclitaxel plus carboplatin combination chemotherapy were included. LNR, defined as the percentage of positive lymph nodes (LNs) to total nodes recovered, was stratified into 3 groups: LNR1 (<10%), LNR2 (10%≤LNR<50%), and LNR3 (≥50%). Kaplan-Meier method was used to generate survival data. Factors predictive of outcome were analyzed using Cox proportional hazards models.

Results

Thirty-one women (13.6%) were classified as stage IIIA1, 15 (6.6%) as stage IIIB, and 183 (79.9%) as stage IIIC. The median age at diagnosis was 56 (range, 18–87), and the median duration of follow-up was 36 months (range, 1–120 months). For the entire cohort, the 5-year overall survival (OS) was 52.8%. An increased LNR was associated with a decrease in 5-year OS from 65.1% for LNR1, 42.5% for LNR2, and 25.6% for LNR3, respectively (p<0.001). In multivariate analysis, women with LNR≥0.50 were 2.7 times more likely to die of their tumors (hazard ratio [HR]=2.7; 95% confidence interval [CI]=1.42–5.18; p<0.001).

Conclusion

LNR seems to be an independent prognostic factor for decreased OS in stage III ovarian HGSC patients.

Contribution of lymph node staging method and prognostic factors in malignant ovarian sex cord-stromal tumors: A world wide database analysis

OBJECTIVE

To investigate the clinicopathologic prognostic factors in patients with malignant sex cord-stromal tumors (SCSTs) with lymph node dissection, and at the same time, to evaluate the influence of the log odds of positive lymph nodes (LODDS) on their survival.

METHODS

Patients diagnosed with malignant SCSTs who underwent lymph node dissection were extracted from the 1988-2013 Surveillance, Epidemiology, and End Results (SEER) database. Overall survival (OS) and cancer-specific survival (CSS) were estimated by Kaplan-Meier curves. The Cox proportional hazards regression model was used to identify independent predictors of survival.

RESULTS

576 patients with malignant SCSTs and with lymphadenectomy were identified, including 468 (81.3%) patients with granulosa cell tumors (GCTs) and 80 (13.9%) patients with Sertoli-Leydig cell tumors (SLCTs). 399 (69.3%) patients and 118 (20.5%) patients were in the LODDS < -1 group and -1 ≤ LODDS < -0.5 group, respectively. The 10-year OS rate was 80.9% and CSS was 87.2% in the LODDS < -0.5 group, whereas the survival rates for other groups were 68.5% and 73.3%. On multivariate analysis, age 50 years or less (p < 0.001), tumor size of 10 cm or less (p < 0.001), early-stage disease (p < 0.001), and GCT histology (p ≤ 0.001) were the significant prognostic factors for improved survival. LODDS < -0.5 was associated with a favorable prognosis (OS: p = 0.051; CSS:P = 0.055).

CONCLUSIONS

Younger age, smaller tumor size, early stage, and GCT histologic type are independent prognostic factors for improved survival in patients with malignant SCST with lymphadenectomy. Stratified LODDS could be regarded as an effective value to assess the lymph node status, and to predict the survival status of patients.

Ratio of positive lymph nodes: The prognostic value in stage IV thyroid cancer

To assess the prognostic value of lymph node ratio (LNR) in patients with stage IV thyroid cancer based on the Surveillance, Epidemiology, and End Results (SEER) database. A total of 4,940 eligible patients were included for the analysis. Kaplan-Meier survival analysis and Cox proportional hazard regression were used to reveal the effect of LNR on overall survival (OS) and disease specific survival (DSS). The optimal cut-off value of LNR for predicting OS and DSS was determined by the time-dependent Receiver Operating Characteristic analysis. By the univariate Cox proportional hazard regression, LNR was significantly associated with OS and DSS in patients with medullary thyroid cancer (MTC), papillary thyroid cancer and anaplastic thyroid cancer (all P < 0.05). With the optimal cut-off value, Kaplan-Meier analysis showed that MTC patients with LNR≥76.5% were significantly associated with poorer OS (log-rank test: P < 0.0001), and LNR≥40.7% were significantly associated with poorer DSS (log-rank test: P < 0.0001). LNR was an independent prognostic factor of poorer survival in MTC patients after adjusting for other variables by multivariable Cox analysis (OS: hazard ratio [HR] = 2.560, 95% confidence interval [CI] 1.690-3.879, P < 0.0001; DSS: HR=2.781, 95% CI 1.582-4.888, P = 0.0004). Our results demonstrated that LNR could predict clinical outcomes in patients with stage IV MTC, and 76.5% was the optimal cut-off value of LNR to predict OS. LNR, as a function of the nodes positive and the nodes examined, could provide suggestions on the postoperative prognosis of patients with stage IV MTC.

Prognostic value of lymph node ratio in stage IIIC epithelial ovarian cancer with node-positive in a SEER population-based study

To assess the prognostic value of the lymph node ratio (LNR) in patients with stage IIIC epithelial ovarian cancer (EOC) with node-positive in a Surveillance, Epidemiology, and End Results (SEER) population-based study. Data of patients were obtained from the SEER database from 1990 to 2012, and analyzed using Kaplan-Meier survival methods and Cox regression proportional hazard model. The prognostic value of the LNR on cause-specific survival (CSS) and overall survival (OS) were calculated. A total of 5,926 patients were identified. Univariate analysis showed that the number of removed lymph nodes (RLNs), the number of positive lymph nodes, and the LNR were significantly associated with CSS and OS (P < 0.05 for all). Multivariate analysis indicated that a higher LNR was an independent prognostic factor for poorer CSS (hazard ratio [HR]: 1.896, 95% confidence interval [CI]: 1.709-2.104, P < 0.001) and OS (HR:1.679, 95% CI: 1.454-1.939, P < 0.001). Among patients with LNR ≤ 0.42 and those with LNR > 0.42, the 5-year CSS was 53.1% and 34.7%, respectively (P < 0.001), and the 5-year OS was 50.4% and 32.0%, respectively (P < 0.001). The prognostic value of the LNR persisted for patients after stratification by the numbers of RLNs, tumor histology, and tumor grade. LNR is a more accurate prognostic method for stage IIIC EOC patients. Patients with a higher LNR are associated with poorer survival in stage IIIC EOC.

Incidence and Impact of Lymph Node Metastases in Advanced Ovarian Cancer: Implications for Surgical Treatment

Background: This study aimed to clarify the impact of node involvement (affected to resected nodes) in optimally cytoreduced (residual tumour ≤1cm) stage IIIC/IV ovarian cancer. Methods: 108 consecutive patients with primary stage IIIC/IV ovarian cancer underwent stage-related surgery and got adjuvant platinum-based chemotherapy. Median follow-up: 53.5 months. All patients got systematic para-aortic and pelvic lymphadenectomy. Clinical parameters were retrospectively evaluated. Patients were stratified into 3 groups to evaluate node affection: 1) no (0%), 2) minor (>0%, ≤50%) >0 and 3) major (>50% of affected nodes). Kaplan-Meier survival curve was used to evaluate the prognostic value. Results: On average, 21.3 pelvic and para-aortic nodes were removed per patient (range 1-60 nodes). Minor nodal involvement (node ratio >0-≤0.5: (59%) was most often detected. Increasing node ratio leads to significant decreased overall survival (p<0.001). Significant best overall survival was associated with minor node involvement (node ratio >0 to ≤0.5). Complete cytoreduction correlated with node affection shows significant best prognostic impact in minor node affection compared to incomplete resection (R>0-≤1cm) independent to nodal status (OS p<0.001). Conclusion: Radical surgery is the main factor of improved overall and tumor free survival. Paraaortal and iliacal lymphadenectomy seems to play an important role for prognostic and therapeutic reasons: Prognostic in accurate staging and therapeutic in case of achieved optimal cytoreduction including lymph nodes with histology proven minor node involvement.

Prevalence, Classification, and Risk Factors for Postoperative Lower Extremity Lymphedema in Women With Gynecologic Malignancies: A Retrospective Study

Objective

Lower extremity lymphedema (LEL) is a major long-term complication of radical surgery. We aimed to estimate the incidence and grading of LEL in women who underwent lymphadenectomy and to evaluate risk factors associated with LEL.

Materials and Methods

We retrospectively reviewed 358 patients with cervical, endometrial, and ovarian cancer who underwent transabdominal complete systematic pelvic and para-aortic lymphadenectomy between 1997 and 2011. Lower extremity lymphedema was graded according to criteria of the International Society of Lymphology. Incidence of LEL and its correlation with various clinical characteristics were investigated using Kaplan-Meier survival and Cox proportional hazards methods.

Results

Overall incidence of LEL was 21.8% (stage 1, 60%; stage 2, 32%; and stage 3, 8%). Cumulative incidence increased with observation period: 12.9% at 1 year, 20.3% at 5 years, and 25.4% at 10 years. Age, cancer type, stage (International Federation of Gynecology and Obstetrics), body mass index, hysterectomy type, lymphocyst formation, lymph node metastasis, and chemotherapy were not associated with LEL. Multivariate analysis confirmed that removal of circumflex iliac lymph nodes (hazard ratio [HR], 4.28; 95% confidence interval [CI], 2.09–8.77; P < 0.0001), cellulitis (HR, 3.48; 95% CI, 2.03–5.98; P < 0.0001), and number of removed lymph nodes (HR, 0.99; 95% CI, 0.98–0.99; P = 0.038) were independent risk factors for LEL.

Conclusions

Postoperative LEL incidence increased over time. The results of the present study showed a significant correlation with removal of circumflex iliac lymph nodes and cellulitis with the incidence of LEL. Multicenter or prospective studies are required to clarify treatment efficacies.

The prognostic relevance of node metastases in optimally cytoreduced advanced ovarian cancer

PURPOSE

To delineate the relevance of pelvic and para-aortic node involvement in optimally cytoreduced (residual tumour <1 cm) stage IIIC ovarian cancer patients.

METHODS

Ninety-five consecutive optimally cytoreduced (R ≤ 1 cm) patients with primary stage IIIc ovarian cancer underwent stage-related surgery and got adjuvant platinum-based chemotherapy. Median follow-up: 53.5 months. All patients got systematic lymphadenectomy. On average, 24.7 pelvic and para-aortic lymph nodes were removed per patient (range 1-60 nodes). Patients were stratified into three groups to evaluate node involvement (ratio: affected to resected nodes): (1) (=0); (2) (>0-≤ 0.5) >0 and ≤ 50 % of affected nodes; (3) (>0.5-≤ 1) >50 % of affected nodes. Clinical parameters were retrospectively evaluated. Kaplan-Meier survival curve was used to evaluate the prognostic value.

RESULTS

Most often serous histology, histologic grade 3 and a node ratio >0-≤ 0.5 (61.1 %) were detected. Complete cytoreduction (R = 0 mm) has significant best prognostic impact compared to R > 0 mm-1 cm (OS: p = 0.047, PFS: p = 0.00). Node involvement was associated with serous histology and grade 3. Increasing node ratio leads to significant decreased OS (p = 0.019) and significant best OS was associated with node ratio >0-≤0.5.

CONCLUSIONS

The goal is optimal cytoreduction in advanced ovarian cancer. More extensive lymphadenectomy seems to play an important role in providing an accurate staging, and the node ratio might give prognostic information. Current prospective studies like the LION study (AGO-Ovar) had to investigate if these data have therapeutic implications and may be considered in future staging.

Prognostic value of lymph node ratio in patients with advanced epithelial ovarian cancer

OBJECTIVE

Lymph node status is an established prognostic factor in epithelial ovarian cancer (EOC). Lymph node ratio (number of positive LN/number of resected LN) reflects both qualitative and quantitative lymph node spread as well as surgical effort and extent of disease. We evaluated whether LNR is a more precise prognostic factor than conventional lymph node status in patients with EOC.

METHODS

The present retrospective study includes 809 patients with EOC, who underwent primary cytoreductive surgery between 2000-2013. Clinico-pathological parameters and survival data were extracted from a prospectively maintained tumor registry database. The optimal cut-off point for LNR was calculated by using Martingale residuals. Survival analyses were calculated using Kaplan-Meier method and Cox regression models.

RESULTS

Lymphadenectomy was performed in 693 (85.7%) out of 809 patients. Median number of removed LN was 64 (IQR 25-75%: 39-84). LNR of 0.25 was identified as the optimal prognostic cut-off value. The estimated 5-year-OS rates were 69.3% for patients with node-negative EOC compared to 33.1% for patients with any lymph node metastasis (p<0.001). The estimated 5-year-OS rates were 42.5% for patients with LNR≤0.25, and 18.0% for patients with LNR>0.25 (p<0.001). Additionally in multivariate analysis LNR>0.25 was approved to be an independent prognostic factor for overall survival (adjusted HR 1.44, 95% CI 1.04-2.00; p=0.028).

CONCLUSION

LNR more precisely predicts overall survival than conventional lymph node status in EOC patients undergoing primary debulking surgery.

Correlation between the extent of intraperitoneal disease and nodal metastasis in node-positive ovarian cancer patients

AIMS

To investigate correlations between extent of disease (ED), frequency and location of nodal metastases in node-positive EOC patients.

METHODS

Data were collected from 116 consecutive patients who underwent systematic lymphadenectomy during primary surgery. Patients were grouped in ED1 (disease confined in pelvis), ED2 (disease extended to abdomen), and ED3 (distant metastases). Univariate and multivariate analysis were performed for overall survival and progression-free survival (PFS).

RESULTS

Correspondence analysis revealed associations between ED1 and negative nodes, ED2 and positive aortic/pelvic nodes, and ED3 and positive external and common iliac nodes. The most representative group for nodal metastases in ED1 was aortic nodes (77.8%). The number of positive pelvic nodes increased with ED; the RR was 0.58 for ED2 and 0.25 for ED3 (p = 0.004). The RR for positive external iliac nodes was 0.66 in ED2 and 0.31 in ED3 (p = 0.002); the RR for positive common iliac nodes was 0.76 and 0.17, respectively (p = 0.001). Multivariate analysis revealed that aortic nodal metastasis was associated with PFS (p = 0.03; HR, 1.95).

CONCLUSION

Distribution and percentage of nodal metastases varied with ED. The risk of pelvic nodal metastasis, increased with ED. Location of positive nodes was correlated with PFS.

Combining the negative lymph nodes count with the ratio of positive and removed lymph nodes can better predict the postoperative survival in cervical cancer patients

BACKGROUND

To evaluate the impacts of the negative lymph nodes (NLNs) count on the prognostic prediction of the ratio of positive and removed lymph nodes (RPL) in cervical cancer patients after radical hysterectomy and pelvic lymphadenectomy (RHPL).

METHODS

The positive and negative lymph node counts were calculated for 609 postoperative cervical cancer patients. The 5-year survival rate (5-YSR) was examined according to clinicopathologic variables. Cox regression was used to identify independent prognostic factors.

RESULTS

The NLNs count cutoffs were determined to be 10 and 25 with 5-YSR of 62.8% and 80.5%. The RPL of 13 patients who had the NLNs count of 10 or fewer was >20%. Among 242 patients who had 10 < NLNs count ≤ 25, 194 without positive nodes had the 5-YSR of 77.8%, 31 with 0% < RPL ≤ 5% had the 5-YSR of 3.2%, 15 with RPL > 20% had died when follow-up was completed. Among 354 patients who had NLNs count >25, 185 without positive nodes had the 5-YSR of 87.6%, 6 with 0% < RPL ≤ 5% had the 5-YSR of 25%, 15 with 5% < RPL ≤ 20% had the 5-YSR of 4.5%, and 2 with RPL >20% had died when follow-up was completed. Furthermore, stage, histologic grade and RPL were independently correlated with overall survival of cervical cancer patients after RHPL in the multivariate analysis.

CONCLUSIONS

RPL was an independent prognostic factor. The NLNs count is a key factor for improvement of survival prediction of RPL in cervical cancer.

Factors influencing the number of pelvic and para-aortic lymph nodes removed in surgical treatment of endometrial and ovarian cancer

OBJECTIVE

This study aimed to determine the number of lymph nodes (LNs) removed in patients who underwent abdominal complete systematic pelvic and para-aortic lymphadenectomy and to identify factors that contribute to disparity in the number of LNs removed.

METHODS

We retrospectively reviewed 260 patients with endometrial cancer and ovarian cancer between 1997 and 2011. All pelvic and para-aortic LNs were submitted as 25 separate packets. The correlations of the number of LNs with age, year of surgery, the operating surgeon, pathologist, body mass index (BMI), histology, clinical stage, operating time, blood loss, and lymph node metastasis were investigated.

RESULTS

The median number of LNs removed was 45 pelvic (17-92) and 25 para-aortic (6-69) LNs. Among pelvic LNs, the common iliac nodes were the most frequently removed followed by the obturator nodes. The median number of the left upper para-aortic LNs between the left renal vein and the inferior mesenteric artery was highest among para-aortic LNs. There were significant correlations between the total number of LNs removed and age (P = 0.036), histology (clear vs serous; P = 0.015), and BMI (P < 0.0001) in ovarian cancer. Features associated with higher LN count on multivariate linear regression analysis included younger patients (P = 0.038) and higher BMI (P = 0.012).

CONCLUSIONS

Age and BMI are independently associated with higher LN counts during LN dissection in ovarian cancer. The present study results may be important when using LN counts as a surrogate for adequate lymphadenectomy.