Extended Lymph Node Dissection Research Articles

Identification of the Optimal Candidates for Nodal Staging with Extended Pelvic Lymph Node Dissection Among Prostate Cancer Patients Who Underwent Preoperative Prostate-specific Membrane Antigen Positron Emission Tomography. External Validation of the Memorial Sloan Kettering Cancer Center and Briganti Nomograms and Development of a Novel Tool

BackgroundAlthough the therapeutic role of extended pelvic lymph node dissection (ePLND) in patients with prostate cancer (PCa) is still under debate, this procedure is recommended for staging purposes in selected cases. Nomograms for predicting lymph node invasion (LNI) do not account for prostate-specific membrane antigen (PSMA) positron emission tomography (PET) imaging, which is characterized by a high negative predictive value for nodal metastases. ObjectiveTo externally validate models predicting LNI in patients with miN0M0 PCa at PSMA PET and to develop a novel tool in this setting. Design, setting, and participantsOverall, 458 patients with miN0M0 disease undergoing radical prostatectomy (RP) and ePLND at 12 centers between 2017 and 2022 were identified. Outcome measurements and statistical analysesAvailable tools were externally validated using calibration plots, the area under the receiver operating characteristic curve (AUC), and decision curve analyses to assess calibration, discrimination, and the net benefit. A novel coefficient-based model was developed, internally validated, and compared with available tools. Results and limitationsOverall, 53 patients (12%) had LNI. The AUC was 69% for the Briganti 2012, 64% for the Briganti 2017, 73% for the Briganti 2019, and 66% for the Memorial Sloan Kettering Cancer Center nomogram. Multiparametric magnetic resonance imaging stage, biopsy grade group 5, the diameter of the index lesion, and the percentage of positive cores at systematic biopsy were independent predictors of LNI (all p ≤ 0.04). Internal cross-validation confirmed a coefficient-based model with AUC of 78%, better calibration, and a higher net benefit in comparison to the other nomograms assessed. Use of a 5% cutoff would have spared 47% ePLND procedures (vs 13% for the Briganti 2019 nomogram) at the cost of missing only 2.1% LNI cases . The lack of central review of imaging and pathology represents the main limitation. ConclusionsTools for predicting LNI are associated with suboptimal performance for men with miN0M0 PCa. We propose a novel model for predicting LNI that outperforms available tools in this population. Patient summaryTools currently used to predict lymph node invasion (LNI) in prostate cancer are not optimal for men with negative node findings on PET (positron emission tomography) scans, leading to a high number of unnecessary extended pelvic lymph node dissection (ePLND) procedures. A novel tool should be used in clinical practice to identify candidates for ePLND to reduce the risk of unnecessary procedures without missing LNI cases.

A multicenter prospective observational study of lymph node metastasis patterns and short-term outcomes of extended lymphadenectomy in right-sided colon cancer.

The lymph node metastasis rate in right-sided colon cancer is unknown, and the optimal central vascular ligation level remains controversial. We aimed to determine the lymph node metastasis rate and short-term results of radical surgery with extended lymph node dissection in right-sided colon cancer. This prospective multicenter observational study included patients with stage II/III right-sided colon cancer from five cancer hospitals. The metastasis rate of each node station was analyzed according to tumor location and main feeding artery. Between April 2018 and August 2021, 208 patients underwent dissection around the superior mesenteric artery (SMA) and vein (SMV). In transverse colon cancer, 7.5% and 2.5% of metastases occurred around the SMV and SMA at the root of the middle colic artery (MCA), respectively; 6.7% and 6.7% at the root of the right colic artery. In caecal cancer, 1.9% of metastases occurred around the SMV and 1.9% around the SMA. In ascending colon cancer, the rate was 1.1% around the SMV. Of the tumors, 17% fed mainly by the ileocolic artery had node metastases along the middle or right colic artery, as did 66.7% fed mainly by the right colic artery and 41.2% fed by the MCA (p = 0.01). Postoperative complications occurred in 42 patients (20.2%). Routine prophylactic extended lymphadenectomy around the SMA might not be necessary in caecum and ascending colon cancer. Dissection around the SMA may be necessary in cases of transverse colon cancer or when the feeding artery is the MCA.

The Sentinel Lymph Node in Treatment Planning: A Narrative Review of Lymph-Flow-Guided Radiotherapy.

The sentinel lymph node technique is minimally invasive and used routinely by surgeons, reducing the need for morbid extensive lymph node dissections, which is a significant advantage for cancer staging and treatment decisions. The sentinel lymph node could also help radiation oncologists to identify tumor drainage for each of their patients, leading to a more personalized radiotherapy, instead of a probabilistic irradiation based on delineation atlases. The aim is both to avoid recurrence in unexpected areas and to limit the volume of irradiated healthy tissues. The aim of our study is to evaluate the impact of sentinel lymph node mapping for radiation oncologists. This concept, relying on sentinel lymph node mapping for treatment planning, is known as lymph-flow-guided radiotherapy. We present an up-to-date narrative literature review showing the potential applications of the sentinel lymph node technique for radiotherapy, as well as the limits that need to be addressed before its routine usage.

Unilateral Pelvic Lymph Node Dissection in Prostate Cancer Patients Diagnosed in the Era of Magnetic Resonance Imaging-targeted Biopsy: A Study That Challenges the Dogma.

Bilateral extended pelvic lymph node dissection at the time of radical prostatectomy is the current standard of care if pelvic lymph node dissection is indicated; often, however, pelvic lymph node dissection is performed in pN0 disease. With the more accurate staging achieved with magnetic resonance imaging-targeted biopsies for prostate cancer diagnosis, the indication for bilateral extended pelvic lymph node dissection may be revised. We aimed to assess the feasibility of unilateral extended pelvic lymph node dissection in the era of modern prostate cancer imaging. We analyzed a multi-institutional data set of men with cN0 disease diagnosed by magnetic resonance imaging-targeted biopsy who underwent prostatectomy and bilateral extended pelvic lymph node dissection. The outcome of the study was lymph node invasion contralateral to the prostatic lobe with worse disease features, ie, dominant lobe. Logistic regression to predict lymph node invasion contralateral to the dominant lobe was generated and internally validated. Overall, data from 2,253 patients were considered. Lymph node invasion was documented in 302 (13%) patients; 83 (4%) patients had lymph node invasion contralateral to the dominant prostatic lobe. A model including prostate-specific antigen, maximum diameter of the index lesion, seminal vesicle invasion on magnetic resonance imaging, International Society of Urological Pathology grade in the nondominant side, and percentage of positive cores in the nondominant side achieved an area under the curve of 84% after internal validation. With a cutoff of contralateral lymph node invasion of 1%, 602 (27%) contralateral pelvic lymph node dissections would be omitted with only 1 (1.2%) lymph node invasion missed. Pelvic lymph node dissection could be omitted contralateral to the prostate lobe with worse disease features in selected patients. We propose a model that can help avoid contralateral pelvic lymph node dissection in almost one-third of cases.

PD15-01 SURVIVAL IN ADJUVANT VS SALVAGE RADIATION THERAPY IN PATHOLOGICAL NODE POSITIVE PROSTATE CANCER PATIENTS: A MULTICENTRIC STUDY

PD15-01 SURVIVAL IN ADJUVANT VS SALVAGE RADIATION THERAPY IN PATHOLOGICAL NODE POSITIVE PROSTATE CANCER PATIENTS: A MULTICENTRIC STUDY

Radical prostatectomy findings in patients with locally aggressive Grade group 5 prostatic adenocarcinoma and negative limited or extended pelvic lymph node dissection

Current management options for high-risk prostate cancer (PCa) patients include radical prostatectomy with lymph node dissection and other local or systemic therapeutic approaches. However, there is paucity of data in the pathology literature on the radical prostatectomy findings in patients with locally aggressive Grade group 5 PCa with negative limited or extended lymph node dissection. A search was made through our Urologic Pathology files and consults of the senior author for patients who had radical prostatectomy specimens with locally aggressive Grade group 5 PCa and limited or extended lymph node dissection from 2010 to 2022. Patients with lymph node metastasis were excluded. Clinicopathologic and follow up data were obtained. Forty-two patients were included in the study. Mean age was 64 years (range: 49–79 years). Forty-one (98 %) patients had PCa Gleason score 4 + 5 = 9 and 1 (2 %) patient had Gleason score 5 + 4 = 9. Extraprostatic extension and/or bladder neck invasion was present in 30 (71 %) patients and seminal vesicle invasion was present in 20 (48 %) patients, of which 10 (50 %) were bilateral. Extended lymph node dissection was performed in 18 patients with mean of 22 lymph nodes (range: 6–51 lymph nodes). Limited lymph node dissection was performed in 24 patients with mean of 7 lymph nodes (range: 2–25 lymph nodes). This study demonstrates that a subset of patients with very advanced/high grade PCa still benefit from radical prostatectomy/tumor debulking even in the setting of positive margins, and may not have lymph node metastasis.

The progression of the extent of lymph node dissection in radical resection of pancreatic head cancer

Pancreatic cancer is a malignant tumor of digestive system with poor prognosis,and surgical resection is still the only hope for a radical cure. Although the current consensus and guidelines describe in detail the standard and extended range of lymph node dissection,the selection of specific range of lymph node dissection and its impact on prognosis are still controversial. Current studies have not only proposed some improved extent of lymph node dissection, such as total mesopancreas excision and Heidelberg triangle dissection, but also suggested different extent of lymph node dissection for ventral and dorsal pancreatic head cancer. In addition, the prognosis of pancreatic head cancer in uncinate process and non-uncinate process is different after para-aortic lymph node dissection, which is worthy of further study. Neoadjuvant therapy or conversion therapy provides more surgical opportunities for patients with pancreatic cancer. For these patients, Heidelberg triangle dissection has potential value in improving prognosis. This paper summarizes the exploration and latest progress of standard and extended lymph node dissection, lymph node dissection of specific site of pancreatic head cancer and the extent of lymph node dissection after neoadjuvant/transformation therapy in recent years.

Comment on: "Reassessment of the Optimal Number of Examined Lymph Nodes in Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma".

We read with great interest the article by Malleo et al1 on the reassessment of the optimal examined lymph node (ELN) in pancreatoduodenectomy for pancreatic ductal adenocarcinoma. Malleo et al1 suggested that 28 and 25 ELNs as the optimal and minimal cutpoints, respectively, significantly improved the detection of N2 disease. We highly appreciate the authors for this innovative statistical method and exciting finding. It is of great clinical significance and may aid in survival prediction and clinical decision-making. However, one of the study’s main points needs further discussion. This study by Malleo et al,1 to determine the optimal or minimal ELNs, was conducted in all patients and ignored the effect of T stage on the optimal ELNs. Current studies found that the optimal ELNs for accurate staging was associated with T stage. Hua et al2 confirmed that the optimal ELNs for the adequate staging of pancreatic cancer was related to the T stage and suggested that at least 16, 21, and 23 ELNs should be examined for T1, T2, and T3 pancreatic cancer, respectively. Similar conclusions were reached in studies of colon and thyroid cancers, strongly implying that the higher the T stage of the tumor, the greater the optimal or minimal ELNs required for accurate staging.3,4 By analyzing the data in Table 1, we found that the proportion of patients with N2 increased with advancing T stage: 35.0%, 51.0%, and 54.7% for T1, T2, and T3 patients (P < 0.001), respectively. Marchegiani et al5 also confirmed that larger pancreatic tumors were associated with more positive lymph nodes and higher lymph node ratios (P < 0.05). This strongly indicated that the risk of staging patients with N2 disease was associated with the T stage. In fact, adequate ELN not only improves the accuracy of lymph node staging but also increases the chance of eradicating isolated tumor cells and micrometastases. Specifically, surgeons may need to examine as many lymph nodes as possible to detect N2 disease and enhance the chance of eradicating isolated tumor cells and micro-metastases in T3 patients. Conversely, for T1 patients, examining more lymph nodes seems less important. Currently, precision medicine, which is based on individual diagnosis and treatment, is at the forefront of cancer research. It brings hope for improving the prognosis of pancreatic cancer. Blindly performing extended lymph node dissection does not improve the prognosis of patients with pancreatic cancer. Instead, extended lymphadenectomy is associated with increased morbidity, operating room time, and length of stay.6 With the advances in medical imaging technology, the T stage is easily obtained in preoperative imaging and may provide guidance on the extent of lymph node dissection. Therefore, optimal and minimal ELN based on the T stage can encourage surgeons to develop individualized lymph node dissection protocols rather than a one-size-fits-all approach, which is also consistent with the essence of precision medicine.

Transrectal Ultrasound-Guided Robotic Excision of Perirectal Lymph Node Metastasis After Primary Radical Prostatectomy

Clinical History: A 60-year-old man with prostate specific antigen (PSA) of 10.8 ng/mL underwent a biopsy that showed grade group (GG) 5 adenocarcinoma of the prostate. The MRI showed organ-confined disease although there was an indeterminate 1 cm node in the left anterolateral perirectal fat. During the robotic radical prostatectomy, bilateral extended node dissection was performed, but the perirectal lymph node was not identifiable. Final pathology report confirmed adenocarcinoma GG5, pT2pN0MxR0, 22 lymph nodes were examined. At 3 months follow-up, PSA was 7.5 ng/mL. Diagnosis: Axumin positron emission tomography and computed tomography showed a solitary hot spot at the location of the perirectal node. We discussed treatment options androgen deprivation therapy, radiotherapy, and surgery. The patient elected for perirectal lymph node dissection (LND). In office contrast-enhanced transrectal ultrasound (TRUS) was performed. This confirmed location and visibility for planned intraoperative TRUS-guided excision. Intervention: Robotic LND started between the rectovesical pouch and the anterolateral aspect of the distal rectum. The node was identified with intraoperative TRUS and then a 17F Chiba needle was placed transrectally through the node into the surgical field. Transfixing the node gave direct vision and guided the robotic LND off the rectal wall and surrounding fat. There were no intraoperative complications, operative time was 214 minutes, estimated blood loss minimum, and length of stay 1 day. Follow-Up: Pathology report confirmed two distinct lymph nodes with metastatic prostatic carcinoma with 14- and 3-mm tumor deposit, respectively. PSA has remained undetectable at last follow-up, 40 weeks after LND. Authors do not have any commercial associations during the past 3 years that might create a conflict of interest in connection with the video. Authors have received and archived patient consent for video recording and publication in advance of video recording of procedure. Runtime of video: 5 mins

Predictor Factors for the Detection of Positive Nodes in Patients Undergoing Radical Prostatectomy and Lymph Node Dissection

Background: The detection of positive lymph nodes after a lymph node dissection changes the clinical prognosis; therefore, we evaluated what factors help us predict the presence of positive lymph nodes. Methods: A retrospective analysis of all radical prostatectomies and extended lymph node dissection performed from January 2010 to October 2018 in our centre was conducted. The variables included in the Briganti nomogram (preoperative PSA, Gleason biopsy, percentage of cores, and clinical stage) were considered, as well as perineural invasion and involvement of the seminal vesicles in the prostate biopsy; Results: A total of 110 lymph node dissections are obtained. Patient mean age is 64.18 years (46.55–75.91). Of the 110 lymphadenectomies performed, 16 patients (14.5%) presented positive nodes. Presenting infiltrated seminal vesicles, perineural invasion, higher PSA, higher clinical stage, higher Gleason biopsy and percentage of cores is more likely to have statistically significant lymph node involvement (p &lt; 0.05). In the multivariate analysis, the percentage of positive core, together with the involvement of the seminal vesicles and Gleason ≥ 4 in the majority are predictor factors for positive nodes (p &lt; 0.01); Conclusions: The percentage of positive cores, the involvement of the seminal vesicles, and the majority Gleason ≥ 4 are independent predictors of lymph node involvement in prostate cancer.

Extension of lymph node dissection in the surgical treatment of esophageal and gastroesophageal junction cancer: seven questions and answers.

The role of two- or three-field nodal dissection in the surgical treatment of esophageal and gastroesophageal junction cancer in the minimally invasive era is still controversial. This review aims to clarify the extension of nodal dissection in esophageal and gastroesophageal junctional cancer. A basic evidence-based analysis was designed, and seven research questions were formulated and answered with a narrative review. Reports with little or no data, single cases, small series and review articles were not included. Three-field lymph node dissection improves staging accuracy, enhances locoregional disease control and might improve survival in the group of patients with cervical and upper mediastinal metastatic lymph nodal involvement from middle and proximal-third esophageal cancer.

18F-JK-PSMA-7 PET/CT for staging intermediate- or high-risk prostate cancer patients before radical prostatectomy: a pilot study

BackgroundPositron emission tomography/computed tomography (PET/CT) using radiotracers that bind to the prostate-specific membrane antigen (PSMA) is mainly used in biochemical recurring prostate cancer. The aim of our study was to assess the usefulness of 18F-JK-PSMA-7 PET/CT for local and nodal staging in patients with intermediate- and high-risk prostate cancer (PCa) prior to radical prostatectomy, as compared to conventional imaging techniques.MethodsWe enrolled a total of 10 patients with intermediate- and high-risk PCa diagnosed by multiparametric-MRI followed by systematic and targeted biopsies, eligible for radical prostatectomy with extended lymph node dissection. Clinical team was blind to the results of the pre-surgery 18F-JK-PSMA-7 PET/CT at times of clinical decision and surgery. One month post-surgery, 18F-JK-PSMA-7 PET/CT was repeated and the results of both scans were unblinded. A third 18F-JK-PSMA-7 PET/CT could be acquired at a later time point depending on PSA progression.ResultsAll pre-surgery 18F-JK-PSMA-7 PET/CT was positive in the prostatic region, while MRI was negative in the prostate in one patient. We also detected positive pelvic lymph nodes in two patients (one high-risk, one intermediate-risk PCa) on pre-surgery and post-surgery 18F-JK-PSMA-7 PET/CT. No positive pelvic lymph nodes were reported on pre-surgical CT and MRI. 18F-JK-PSMA-7 PET/CT detected bladder involvement in one patient and seminal vesicles involvement in two patients; this malignant extension was undetected by the conventional imaging techniques. SUVmax in prostate lesions had an average value of 11.51 (range 6.90–21.49). SUVmean in prostate lesions had an average value of 7.59 (range 5.26–14.02).ConclusionThis pilot study indicates that pre-surgery 18F-JK-PSMA-7 PET/CT provides valuable information in intermediate- and high-risk PCa, for surgery planning with curative intent.

Prognostic Impact of Main Lymph Node Metastasis in Patients with Colon Cancer.

Although extended lymph node dissection during colon cancer surgery is recommended in both Western and Eastern countries, the perception and clinical significance of main lymph node metastasis (MLNM) remains controversial. In total, 1557 patients with colon cancer who underwent curative resection with D3 dissection were retrospectively analyzed. Clinicopathological factors associated with MLNM were analyzed. Kaplan-Meier survival analysis and log-rank tests were used to compare the prognosis between the MLNM and non-MLNM groups. Multivariate analysis showed that overall survival (OS) [hazard ratio, 2.117 (0.939-4.774), p = 0.071] and recurrence-free survival (RFS) [hazard ratio, 2.183 (1.182-4.031), p = 0.013] were affected by the MLNM status independent of the TNM stage. Survival analysis demonstrated that among patients with stage III disease, the OS and RFS rates were significantly different between patients with and without MLNM (OS: p = 0.0147, RFS: p = 0.0001). However, the OS and RFS rates were not significantly different between patients who had stage III disease with MLNM and patients who had stage IV disease (OS: p = 0.5901, RFS: p = 0.9610). MLNM is an independent prognostic factor for patients with colon cancer. The addition of the MLNM status to the current TNM classification may enhance the prognostic value of the TNM staging system and the clinical efficacy of adjuvant therapy in patients with colon cancer.

Performance of Node-RADS Scoring System for a Standardized Assessment of Regional Lymph Nodes in Bladder Cancer Patients.

Current cross-sectional imaging modalities exhibit heterogenous diagnostic performances for the detection of a lymph node invasion (LNI) in bladder cancer (BCa) patients. Recently, the Node-RADS score was introduced to provide a standardized comprehensive evaluation of LNI, based on a five-item Likert scale accounting for both size and configuration criteria. In the current study, we hypothesized that the Node-RADS score accurately predicts the LNI and tested its diagnostic performance. We retrospectively reviewed BCa patients treated with radical cystectomy (RC) and bilateral extended pelvic lymph node dissection, from January 2019 to June 2022. Patients receiving preoperative systemic chemotherapy were excluded. A logistic regression analysis tested the correlation between the Node-RADS score and LNI both at patient and lymph-node level. The ROC curves and the AUC depicted the overall diagnostic performance. In addition, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for different cut-off values (>1, >2, >3, >4). Overall, data from 49 patients were collected. Node-RADS assigned on CT scans images, was found to independently predict the LNI after an adjusted multivariable regression analysis, both at the patient (OR 3.36, 95%CI 1.68-9.40, p = 0.004) and lymph node (OR 5.18, 95%CI 3.39-8.64, p < 0.001) levels. Node-RADS exhibited an AUC of 0.87 and 0.91 at the patient and lymph node levels, respectively. With increasing Node-RADS cut-off values, the specificity and PPV increased from 57.1 to 97.1% and from 48.3 to 83.3%, respectively. Conversely, the sensitivity and NPV decreased from 100 to 35.7% and from 100 to 79.1%, respectively. Similar trends were recorded at the lymph node level. Potentially, Node-RADS > 2 could be considered as the best cut-off value due to balanced values at both the patient (77.1 and 78.6%, respectively) and lymph node levels (82.4 and 93.4%, respectively). The current study lays the foundation for the introduction of Node-RADS for the regional lymph-node evaluation in BCa patients. Interestingly, the Node-RADS score exhibited a moderate-to-high overall accuracy for the identification of LNI, with the possibility of setting different cut-off values according to specific clinical scenarios. However, these results need to be validated on larger cohorts before drawing definitive conclusions.

Current surgical concepts and future perspectives in the treatment of pancreatic cancer

Over the past 20 years, the concept of pancreatic surgery has been updated and surgical skills has improved dramatically. With the significant improvement of surgical safety and increase of resection rate for pancreatic cancer, some traditional surgical issues such as surgical indications, timing and extent of resection are being re-evaluated. The improvement of patients' prognosis is the gold standard for judging the surgical indications. The traditional criteria of "unresectable" based on morphology will be constantly broken through, and the estimation of resectability will transition from "what can we resect" to "what should we resect". Except for clinical research, standard extent of lymph node dissection is recommended. However, for borderline resectable and locally advanced pancreatic cancer after neoadjuvant treatment, extended lymph node dissection is recommended. All kinds of surgical approaches are feasible. The approach is subject to the needs of anatomy, anatomy is subject to the needs of radical treatment, and radical treatment is subject to the needs of improving prognosis. For some patients with locally advanced pancreatic cancer, sub-adventitial divestment of superior mesenteric artery and "Heidelberg triangle" cleaning are helpful to improve the resection rate and reduce the local recurrence rate,however, the impact on the long-term prognosis still needs to be further observed clinically. The quality of pancreaticojejunostomy has more influence on the incidence of pancreatic fistula than the type of pancreaticojejunostomy. For the centers with high volume patients and the surgeons with rich personal experience, laparoscopic or robot assisted surgery has the advantages of minimally invasive, but for pancreatic head carcinoma, it is not enough evidence to prove the oncological advantages of laparoscopic pancreaticoduodenectomy and robotic-assistant pancreaticoduodenectomy.

Outcomes of Gastrectomy for Gastric Cancer in Patients Aged >80 Years: A Systematic Literature Review and Meta-Analysis.

This meta-analysis examined the surgical management of older patients (>80 years) with gastric cancer, who were often excluded from randomized controlled trials. We analyzed 23 retrospective cohort studies involving 18,372 patients and found that older patients had a higher in-hospital mortality rate (relative risk [RR], 3.23; 95% confidence interval [CI], 1.46-7.17; P<0.01) and more post-operative complications (RR, 1.36; 95% CI, 1.19-1.56; P<0.01) than did younger patients. However, the surgical complications were similar between the two groups. Older patients were more likely to undergo less extensive lymph node dissection and longer hospital stays. Although older patients had statistically significant post-operative medical complications, they were not deprived of surgery for gastric cancer. The comorbidities and potential risks of post-operative complications should be carefully evaluated in older patients, highlighting the importance of careful patient selection. Overall, this meta-analysis provides recommendations for the surgical management of older patients with gastric cancer. Careful patient selection and evaluation of comorbidities should be performed to minimize the risk of post-operative complications in older patients, while recognizing that they should not be deprived of surgery for gastric cancer.

Indications, Safety, Efficacy and Survival Benefit of Intraperitoneal Chemotherapy in Patients With Advanced Gastric Cancer.

Advanced gastric cancer remains a significant concern for the medical community mostly due to the locoregional extension of the disease. Most commonly, stomach neoplasms are resectable, but not curable, due to the elevated percentage of peritoneal dissemination after gastrectomy and extensive lymph node dissection. Locoregional intraperitoneal chemotherapy plays a pivotal role in overall survival and prognosis of patients with advanced gastric cancer and shows a high probability of peritoneal dissemination after gastrectomy. In this review, we aimed to collect and present literature data concerning intraperitoneal chemotherapy in advanced stages of gastric cancer as well as evaluate the safety and survival benefit of the procedure. We conducted a survey including all randomized controlled trials and clinical trials that were published in the last 30 years. The keywords used were: advanced gastric cancer, intraperitoneal chemotherapy and peritoneal carcinomatosis. We searched for clinical trials in Pubmed, Embase databases and the Cochrane library. Inclusion criteria were: patients with advanced gastric cancer with no macroscopical signs of peritoneal dissemination, who were treated with D2 gastrectomy and received one or more cycles of intraperitoneal chemotherapy. The final review included 20 articles. The safety of intraperitoneal chemotherapy, as well as the survival benefit of patients were evaluated. The majority of articles denoted that intraperitoneal chemotherapy is a safe procedure without severe or lethal complications. The majority of complications were hematological while non-hematologic complications were also noted. A survival benefit with statistically significant results (p<0.05) was observed in 6 out of 10 randomized controlled trials. Intraperitoneal chemotherapy for advanced gastric cancer is a safe procedure with promising results regarding survival benefit and prognosis. Further patient evaluation is required in order to standardize the type of chemotherapeutic agent and the sufficient dose and cycles for the most appropriate results.

The Effect of a Peritoneal Iliac Flap on Lymphocele Formation After Robotic Radical Prostatectomy: Results From the PLUS Trial

To assess the effectiveness of a peritoneal flap on the formation of lymphoceles after robotic assisted radical prostatectomy with bilateral extended pelvic lymph node dissection. We conducted a single surgeon, assessor blinded prospective randomized controlled trial (the Prospective Lymphocele Ultrasound Study) in men undergoing robotic assisted radical prostatectomy with bilateral extended pelvic lymph node dissection. At the conclusion of the node dissection, patients were block randomized 1:1 to either standard of care (no bladder peritoneal flap) or to the creation of a bladder peritoneal flap. Lymphocele formation was assessed by pelvic ultrasound postoperatively. The primary outcome was lymphocele formation. Rates of lymphocele formation and complications were analyzed using chi-square. Other outcomes, including length of stay, number of lymph nodes removed, lymphocele volume, and quality of life measures, were analyzed by t-tests or Wilcoxon Ranked Sum Tests, as appropriate. An a priori power calculation was performed using O'Brien-Fleming alpha sharing for the interim analyses. Two preplanned interim analyses were performed when 45 and 90 patients per group had follow-up ultrasounds. A statistically significant difference in lymphocele formation was seen on the second interim analysis for 183 patients (4.3% vs. 15.6%, p=.011) stopping enrollment; this remained significant in the final analysis of 216 patients (3.6% vs 14.2%, p=.006). No other significant differences were observed. This prospective randomized trial supports the implementation of this simple modification for robotic assisted radical prostatectomy with bilateral extended pelvic lymph node dissection.

PSAT280 Role of Radiofrequency Ablation Therapy in Recurrent Papillary Thyroid Carcinoma - A Case Study

Abstract Introduction Radiofrequency ablation (RFA) has been studied in solitary and reoccurring/ persistent papillary thyroid cancer (PTC) with favorable results. This case describes a patient with reoccurring PTC who underwent radiofrequency ablation. Clinical Case This is a case of a 68 year old male who was underwent an elective thyroid surgery for compressive multinodular goiter and left inferior parathyroid adenoma. Prior to his surgery he had fine needle aspiration cytologies of multiple nodules that were negative for thyroid cancer. A total thyroidectomy with excision of central cervical lymph nodes, excision of a suspicious right perithyroidal mass and a left inferior parathyroidectomy were performed. The pathology diagnosis was multifocal bilateral papillary thyroid cancer – classical type – with infiltration into perithyroidal adipose tissue and lymph node metastasis (pathological stage: mpT1b pN1a). Serum thyroglobulin was 4.9 ng/mL (reference range 1.6–59.9 ng/mL). Postoperatively, he was given adjuvant radioactive iodine (I-131 120mCi) treatment and suppressive levothyroxine at 250 µg daily, with pretreatment TSH at 14.730 µU/mL and TSH after 4 months of treatment 0.140 µU/mL. Single photon emission computed tomography (SPECT) whole body imaging done seven days post radioactive iodine therapy showed no evidence of distant metastases. Four months after I-131 therapy, a diagnostic ultrasound for a palpable node revealed this to be a right level IIb cystic cervical lymph node (18×16×18 mm) with no overt vascularity. Serum thyroglobulin was &amp;lt;0.2 ng/mL and thyroglobulin antibodies were &amp;lt;14.4 IU/mL. FNA biopsy, with cytology showing papillary thyroid cancer. Needle washout thyroglobulin was elevated (1015.3 ng/mL, reference range &amp;lt; 10ng/mL). This metastatic lymph node was concluded to be recurrent papillary cancer. Surgical dissection and percutaneous alternatives were discussed with the patient. Shared decision making between surgery, intervention radiology and the patient concluded that a less invasive procedure was preferred and the solitary node was a candidate for percutaneous ablation. Post ablation surveillance ultrasonography showed an 80% volume reduction (11×8×12 mm) in node size six weeks post intervention and a 95% volume reduction at six months (8×5×7 mm), with decreased cystic appearance and no vascularity. No complications were reported after the procedure. Conclusion Current guidelines recommend that the mainstay of recurrent thyroid cancer is surgery, followed by radioactive iodine therapy and suppressive thyroid hormone replacement treatment, external beam radiotherapy and/ or chemotherapy. However within recent years, image guided ablation techniques such as radiofrequency ablation has been explored and has become an alternative in selective who wish to avoid extensive lymph node dissection. Multiple studies unanimously report a node volume reduction rate (VRR) of greater than 50%, with some studies reporting almost 99% VRR within 12-24 months; suggesting a role for RFA to replace 'berry picking surgery' in selected patients. Presentation: No date and time listed

Clinical significance of limited and extended pelvic lymph node dissection during robot-assisted radical prostatectomy for patients with localized prostate cancer: A retrospective, propensity score matching analysis.

We investigated the diagnostic and therapeutic benefits of limited or extended pelvic lymph node dissection during a robot-assisted radical prostatectomy for localized prostate cancer. Diagnostic and therapeutic benefits were assessed according to the rates of pN1 and biochemical recurrence, respectively. The primary outcome was the biochemical recurrence-free rate, and secondary outcomes included the diagnostic and therapeutic benefits of pelvic lymph node dissection. A total of 534 patients were analyzed. Out of the 534 patients, 207 (38.8%) received limited pelvic lymph node dissection while 134 (25.1%) received extended dissection. There were 297 patients with a Briganti index ≥5%. Extended dissections yielded significantly more resected lymph nodes (p < 0.0001), and 72.2% of cases of pN1 were located outside the obturator. The incidence rate of pN1 was 6.1%, and performance of extended lymph node dissection was an independent predictor for pN1 (odds ratio 9.0, 95% confidence interval 2.5-33.1). The rate of biochemical recurrence was 14.9%, and Cox proportional hazards regression analysis of the propensity score matched population revealed that patients with high or very-high risk tended to benefit from limited lymph node dissection (hazard ratio 8.4, 95% confidence interval 0.8-82.3) while the therapeutic benefit of extended dissection was unclear by comparison. Extended pelvic lymph node dissection significantly improves diagnostic accuracy; however, the therapeutic benefit of pelvic lymph node dissection was not observed in this study.