Assessment of Updated Commission on Cancer Guidelines for Intraoperative Lymph Node Sampling in Early Stage NSCLC

INTRODUCTION

The American College of Surgeons Commission on Cancer recently updated its sampling recommendations for early stage NSCLC from at least 10 lymph nodes to at least one N1 (hilar) and three N2 (mediastinal) lymph node stations. Nevertheless, intraoperative lymph node sampling minimums remain subject to debate. We sought to evaluate these guidelines in patients with early stage NSCLC.

METHODS

We performed a cohort study using a uniquely compiled data set from the Veterans Health Administration. We manually abstracted data from operative notes and pathology reports of patients with clinical stage I NSCLC receiving surgery (2006-2016). Adequacy of lymph node sampling was defined using count-based (≥10 lymph nodes) and station-based (≥three N2 and one N1 nodal stations) minimums. Our primary outcome was recurrence-free survival. Secondary outcomes were overall survival and pathologic upstaging.

RESULTS

The study included 9749 patients. Count-based and station-based sampling guidelines were achieved in 3302 (33.9%) and 2559 patients (26.3%), respectively, with adherence to either sampling guideline increasing over time from 35.6% (2006) to 49.1% (2016). Adherence to station-based sampling was associated with improved recurrence-free survival (multivariable-adjusted hazard ratio = 0.815, 95% confidence interval: 0.667-0.994, p = 0.04), whereas adherence to count-based sampling was not (adjusted hazard ratio = 0.904, 95% confidence interval: 0.757-1.078, p = 0.26). Adherence to either station-based or count-based guidelines was associated with improved overall survival and higher likelihood of pathologic upstaging.

CONCLUSIONS

Our study supports station-based sampling minimums (≥three N2 and one N1 nodal stations) for early stage NSCLC; however, the marginal benefit compared with count-based guidelines is minimal. Further efforts to promote widespread adherence to intraoperative lymph node sampling minimums are critical for improving patient outcomes after curative-intent lung cancer resection.

Para-aortic lymph node involvement should not be a contraindication to resection of pancreatic ductal adenocarcinoma

BACKGROUND

Para-aortic lymph nodes (PALN) are found in the aortocaval groove and they are staged as metastatic disease if involved by pancreatic ductal adenocarcinoma (PDAC). The data in the literature is conflicting with some studies having associated PALN involvement with poor prognosis, while others not sharing the same results. PALN resection is not included in the standard lymphadenectomy during pancreatic resections as per the International Study Group for Pancreatic Surgery and there is no consensus on the management of these cases.

AIM

To investigate the prognostic significance of PALN metastases on the oncological outcomes after resection for PDAC.

METHODS

This is a retrospective cohort study of data retrieved from a prospectively maintained database on consecutive patients undergoing pancreatectomies for PDAC where PALN was sampled between 2011 and 2020. Statistical comparison of the data between PALN+ and PALN- subgroups, survival analysis with the Kaplan-Meier method and risk analysis with univariable and multivariable time to event Cox regression analysis were performed, specifically assessing oncological outcomes such as median overall survival (OS) and disease-free survival (DFS).

RESULTS

81 cases had PALN sampling and 17 (21%) were positive. Pathological N stage was significantly different between PALN+ and PALN- patients (P = 0.005), while no difference was observed in any of the other characteristics. Preoperative imaging diagnosed PALN positivity in one case. OS and DFS were comparable between PALN+ and PALN- patients with lymph node positive disease (OS: 13.2 mo vs 18.8 mo, P = 0.161; DFS: 13 mo vs 16.4 mo, P = 0.179). No difference in OS or DFS was identified between PALN positive and negative patients when they received chemotherapy either in the neoadjuvant or in the adjuvant setting (OS: 23.4 mo vs 20.6 mo, P = 0.192; DFS: 23.9 mo vs 20.5 mo, P = 0.718). On the contrary, when patients did not receive chemotherapy, PALN disease had substantially shorter OS (5.5 mo vs 14.2 mo; P = 0.015) and DFS (4.4 mo vs 9.8 mo; P < 0.001). PALN involvement was not identified as an independent predictor for OS after multivariable analysis, while it was for DFS doubling the risk of recurrence.

CONCLUSION

PALN involvement does not affect OS when patients complete the indicated treatment pathway for PDAC, surgery and chemotherapy, and should not be considered as a contraindication to resection.

Adequacy of Mediastinal Lymph Node Sampling in Patients With Lung Cancer Undergoing Lung Resection

BACKGROUND

Intraoperative mediastinal lymph node sampling (MLNS) is a crucial component of lung cancer surgery. Whilst several sampling strategies have been clearly defined in guidelines from international organizations, reports of adherence to these guidelines are lacking. We aimed to assess our center's adherence to guidelines and determine whether adequacy of sampling is associated with survival.

MATERIALS AND METHODS

A single-center retrospective review of consecutive patients undergoing lung resection for primary lung cancer between January 2013 and December 2018 was undertaken. Sampling adequacy was assessed against standards outlined in the International Association for the Study of Lung Cancer 2009 guidelines. Multivariable logistic and Cox proportional hazards regression analyses were used to assess the impact of specific variables on adequacy and of specific variables on overall survival, respectively.

RESULTS

A total of 2380 patients were included in the study. Overall adequacy was 72.1% (n= 1717). Adherence improved from 44.8% in 2013 to 85.0% in 2018 (P< 0.001). Undergoing a right-sided resection increased the odds of adequate MLNS on multivariable logistic regression (odds ratio 1.666, 95% confidence interval [CI]: 1.385-2.003, P< 0.001). Inadequate MLNS was not significantly associated with reduced overall survival on log rank analysis (P= 0.340) or after adjustment with multivariable Cox proportional hazards (hazard ratio 0.839, 95% CI 0.643-1.093).

CONCLUSIONS

Adherence to standards improved significantly over time and was significantly higher for right-sided resections. We found no evidence of an association between adequate MLNS and overall survival in this cohort. A pressing need remains for the introduction of national guidelines defining acceptable performance.

Standardizing lymph nodal sampling for Wilms tumor: A feasibility study with outcomes

BACKGROUND

Despite being mandated by cooperative groups, omission of nodal sampling is the most frequent protocol deviation in surgery for Wilms tumor. The stations as well as the number of nodes that should be sampled are not clearly defined resulting in a marked variation in practices among surgeons. We propose a systematic method for nodal sampling intending to reduce interoperator variation. In this study, we have assessed the feasibility and yield of systematic lymph node sampling and also evaluated the factors influencing nodal metastasis.

METHODS

Prospective evaluation of 113 Wilms tumor patients operated at a single tertiary cancer center between 2015 and 2019. All these patients underwent a systematic 5-station nodal sampling.

RESULTS

Median lymph node yield was 8 and 13.2% (15/113) patients harbored a histologically positive nodal disease. Of the patients with positive nodal disease, interaortocaval nodes had metastasis in 46.7% (n = 7). They represented isolated sites of nodal disease (skip metastases) in 28.6% (n = 4) of patients. Right-sided tumors had more frequent involvement of interaortocaval nodes and skip disease. Tumors with high-risk histology had 12.5 times more odds of harboring nodal disease as compared to low and intermediate-risk histology Wilms tumor.

CONCLUSIONS

The proposed method of systematic station wise sampling provides a template to guide surgeons in performing lymph node harvesting. Interaortocaval nodes sampling should be performed routinely as the incidence of disease at this station is sufficiently high and metastasis may skip hilar nodes.

STUDY OF DIAGNOSTIC TEST

Level III evidence.

Is there any therapeutic role of pelvic and para-aortic lymphadenectomy in apparent early stage epithelial ovarian cancer?

OBJECTIVE

The therapeutic role of pelvic and para-aortic lymphadenectomy in surgical staging of apparent early-stage epithelial ovarian cancer (eEOC) is still under debate. The aim of this study was to evaluate the potential therapeutic role of systematic lymphadenectomy in patients with eEOC.

METHODS

Multi-center retrospective cohort study, comparing women with apparent eEOC who underwent comprehensive bilateral pelvic and para-aortic lymphadenectomy (defined as ≥20 lymph nodes) versus patients receiving no lymphadenectomy or lymph node sampling, from 05/1985 to 12/2016. Patients with bulky nodes at CT-scan and those without complete intra-peritoneal surgical staging were excluded. Only patients who received at least 3 cycles of platinum-based adjuvant chemotherapy were included.

RESULTS

Out of 2559 patients with FIGO stage IA-IIIA1 ovarian cancer, 639 (25.0%) met inclusion criteria. 360 (56.3%) underwent comprehensive lymphadenectomy, 150 (23.5%) lymph node sampling and 129 (20.2%) no lymphadenectomy. Patients who underwent comprehensive lymphadenectomy were younger (p < 0.001), experienced a higher number of severe post-operative complications (p = 0.008) and had a longer time to start chemotherapy (p = 0.034). There was no difference in intra-operative complications. Median follow-up was 63 months (range, 5-342). The 5-year disease-free survival (DFS) was 79.7% vs. 76.5% vs. 68.3% (p = 0.006), and 5-year overall survival (OS) was 92.3% vs. 94.5% vs. 89.8% (p = 0.165) in women who received comprehensive lymphadenectomy vs. lymph node sampling vs. no lymphadenectomy, respectively. Lymphadenectomy represented an independent factor for DFS improvement, HR 0.52 (95%CI 0.37-0.73) (p < 0.001).

CONCLUSION

Pelvic and para-aortic lymphadenectomy in surgical staging of eEOC improves DFS for the price of increasing post-operative complications and time to chemotherapy but does not affect OS. Better understanding of tumor biology may help to identify those patients in whom lymphadenectomy should still play a role.

The prognostic impact of neoadjuvant chemoradiotherapy on lymph node sampling in patients with locally advanced rectal cancer

According to the American Joint Committee on Cancer, at least 12 lymph nodes are required to accurately stage locally advanced rectal cancer (LARC). Neoadjuvant chemoradiation therapy (NACRT) reduces the number of lymph nodes retrieved during surgery. In this study, we evaluated the effect of NACRT on lymph node retrieval and prognosis in patients with LARC. We performed an observational study of 142 patients with LARC. Although our analysis was retrospective, data were collected prospectively. Half the patients were treated with NACRT and total mesorectal excision (TME) and the other half underwent TME only. The number of lymph nodes retrieved and the number of metastatic lymph nodes were significantly reduced in the NACRT group (P > 0.001). In the univariate and multivariate analyses, only NACRT and patient age were significantly associated with reduced lymph node retrieval. The number of metastatic lymph nodes and the lymph node ratio (LNR) both had a significant effect on prognosis when the patient population was examined as a whole (P = 0.003 and P = 0.001, respectively). However, the LNR was the only significant, independent prognostic factor in both treatment groups (P = 0.007 for the NACRT group; P = 0.04 for the no-NACRT group). NACRT improves patient prognosis only when the number of metastatic lymph nodes is reduced. The number of metastatic lymph nodes and the LNR are important prognostic factors. Lymph node retrieval remains an indispensable tool for staging and prognostic assessment of patients with rectal carcinoma treated with NACRT.

Factors related to lymph node sampling at the time of surgery in children, adolescents, and young adults with unilateral non-metastatic renal cell carcinoma

INTRODUCTION

Renal cell carcinoma (RCC) is rare in the pediatric, adolescent, and young adult (PAYA) population. PAYA patients with RCC have a high rate of lymph node (LN) involvement, regardless of primary tumor size, yet data to guide surgical LN management in this group are limited.

OBJECTIVE

The objective of this study was to determine what factors are associated with LN sampling (protocol adherence) in PAYAs with RCC.

METHODS

The National Cancer Database (NCDB) between 2004 and 2013 was queried for patients aged ≤30 yrs with non-metastatic, unilateral RCC managed with surgery. Logistic regression analyses were performed to evaluate factors associated with LN sampling.

RESULTS

A total of 2857 patients met study criteria. Pathologically, 2510 (87.8%) patients were Nx, 278 (9.7%) N0, and 69 (2.4%) N1. Older age was associated with omission of LN sampling (odds ration [OR]: 1.065, 95% confidence interval [CI]: 1.04-1.1, P < 0.001). Higher institutional volume (OR: 0.971, 95% CI: 0.96-0.99, P < 0.001), stage 3 tumors (OR: 0.19, 95% CI: 0.11-0.33, P < 0.001), pre-operative clinical node involvement (OR: 0.32, 95% CI: 0.12-0.86, P = 0.024), tumor size >10 cm (OR: 0.27, 95% CI: 0.12-0.57, P = 0.001), and radical nephrectomy (OR: 0.245, 95% CI: 0.16-0.38, P < 0.001) were associated with patients undergoing LN sampling.

DISCUSSION

Lymph node sampling is performed in <15% of PAYA patients with RCC. Given the higher rate of translocation RCC pathology in younger patients, which leads to a higher prevalence of nodal involvement (especially with small masses), and the subsequent need for aggressive surgical control of disease, LN sampling and protocol adherence are potentially underutilized in this population and may present a unique opportunity for urologists to improve the care of PAYAs. Data from administrative databases are helpful for rare diseases such as PAYA RCC, but comes with limitations such as missing data. There are several factors that could contribute to LN sampling utilization (National comprehensive cancer network (NCCN) or Children's Oncology Group institution designation, surgeon experience, annual volume, specialty, operative approach, etc.) that cannot be further examined using the NCDB.

CONCLUSION

Pediatric, adolescent, and young adult patients with localized RCC are less likely to undergo surgical LN sampling if they are older, have tumors <10 cm or of less advanced stage, have no pre-operative clinical suspicion of LN involvement, are treated with partial nephrectomy, or are treated at lower volume centers. It appears that approaches from adults with RCC are being applied to PAYAs despite evidence that PAYAs with RCC experience a significant rate of LN involvement even with small tumors.

Lymph Node Sampling and Survival in Child and Adolescent Extremity Soft-Tissue Sarcoma

BACKGROUND

The significance of lymph node sampling (LNS) on disease-specific survival (DSS) of extremity soft tissue sarcomas (STS) is unknown. We investigated the effect of LNS on DSS in child and adolescent extremity STS.

MATERIALS AND METHODS

The Surveillance, Epidemiology, and End Results registry was queried for patients aged <20 y with extremity STS who underwent surgery. Patient demographics were collected and analyzed.

RESULTS

A total of 1550 patients were included, with findings of 10-y DSS of 74% for all extremity STS and 49% for rhabdoymyosarcoma (RMS) (P < 0.005). LNS was associated with worse DSS in patients with extremity nonrhabdomyosacrcoma soft tissue sarcomas (79% versus 84%, P = 0.036). Conversely, LNS was associated with an improved DSS in patients with extremity RMS (64% versus 49%, P = 0.005).

CONCLUSIONS

LNS is positively associated with an improved DSS in child and adolescent extremity RMS. Multivariate analysis found no correlation between DSS and LNS in child and adolescent extremity nonrhabdomyosarcoma soft tissue sarcomas.

Incidence and outcomes of pediatric extremity melanoma: A propensity score matched SEER study

BACKGROUND

There is a paucity of literature on treatment of melanoma in children with surgical management extrapolated from adult experience. The incidence and clinical outcomes of pediatric extremity melanoma were studied.

METHODS

SEER registry was analyzed between 1973 and 2010 for patients <20years old with extremity melanoma. Multivariate and propensity-score matched analyses were performed to identify independent predictors of survival.

RESULTS

Overall, 917 patients were identified with an age-adjusted incidence of 0.2/100,000 persons, annual percent change 0.96. Most had localized disease (77%), histology revealing melanoma-not otherwise specified (52%). Surgical procedures performed included wide local excision (50%), excisional biopsy (32%), lymphadenectomy (LA) (28%), and sentinel lymph node biopsy (SLNB) (15%). Overall, 30-year disease specific mortality was 7% with lower survival for extremity melanoma (90%), males (89%), nodular histology (69%), and distant disease (36%) (all P<0.05). Post-treatment multivariate analysis revealed localized disease (HR 9.76; P=0.006) as an independent prognosticator of survival; earlier diagnostic years 1988-1999 (HR 2.606; P=0.017) were a negative prognosticator of survival. Propensity-score matched analysis found no difference in survival between SLNB/LA vs no sampling for regional/distant disease.

CONCLUSIONS

Pediatric extremity melanoma in SEER demonstrate no survival advantage between children undergoing sampling procedures vs no sampling for regional/distant disease.

TYPE OF STUDY

Retrospective, prognostic study.

LEVEL OF EVIDENCE

III.

A single surgeon's experience transitioning to robotic-assisted right colectomy with intracorporeal anastomosis

BACKGROUND

Despite substantial evidence demonstrating benefits of minimally invasive surgery, a large percentage of right colectomies are still performed via an open technique. Most laparoscopic right colectomies are completed as a hybrid procedure with extracorporeal anastomosis. As part of a pure minimally invasive procedure, intracorporeal anastomosis (ICA) may confer additional benefits for patients. The robotic platform may shorten the learning curve for minimally invasive right colectomy with ICA.

METHODS

From January 2014 to May 2016, 49 patients underwent robotic-assisted right colectomy by a board-certified colorectal surgeon (S.R). Extracorporeal anastomosis (ECA) was used in the first 20 procedures, whereas ICA was used in all subsequent procedures. Outcomes recorded in a database for retrospective review included operating time (OT), estimated blood loss (EBL), length of stay (LOS), conversion rate, complications, readmissions, and mortality rate.

RESULTS

Comparison of average OT, EBL, and LOS between extracorporeal and intracorporeal groups demonstrated no significant differences. For all patients, average OT was 141.6 ± 25.8 (range 86-192) min, average EBL was 59.5 ± 83.3 (range 0-500) mL, and average LOS was 3.4 ± 1.19 (range 1.5-8) days. Four patients required conversion, all of which occurred in the extracorporeal group. There were no conversions after the 18th procedure. The 60-day mortality rate was 0%. There were no anastomotic leaks, ostomies created, or readmissions. As the surgeon gained experience, a statistically significant increase in lymph node sampling was observed in oncologic cases (p = .02).

CONCLUSIONS

The robotic platform may help more surgeons safely and efficiently transition to a purely minimally invasive procedure, enabling more patients to reap the benefits of less invasive surgery. Transitioning from ECA to ICA during robotic right colectomy resulted in no significant change in OT or LOS. A lower rate of conversion to open surgery was noted with increased experience.

Quality assessment of lymph node sampling in rhabdomyosarcoma: A surveillance, epidemiology, and end results (SEER) program study

BACKGROUND

Lymph node sampling is integral in the management of extremity and paratesticular rhabdomyosarcoma (RMS). The aim of this study was to determine overall surgical compliance with treatment protocols and impact of nodal sampling outcomes in these tumors.

METHODS

A query of the surveillance, epidemiology, and end results program (SEER) database was performed from 2003 to 2008 for patients <19years of age with RMS. Data obtained included demographics, five-year survival and rate of nodal sampling. Analysis was performed utilizing chi-squared, Kaplan-Meier and hazard ratio modeling.

RESULTS

Of 537 patients with extremity RMS, nodal sampling was performed in 25.7% (n=138). This lack of nodal sampling had a negative outcome on survival (p=0.004). Sixty five patients with paratesticular RMS aged greater than 10 were identified and also displayed low rates of lymph node sampling (47.7%, n=31). For paratesticular patients, a similar increase in survival was seen in patients who underwent nodal evaluation (p=0.024).

CONCLUSION

Lymph node sampling is the standard of care in RMS. However, surgical compliance with treatment protocols is poor. Nodal evaluation correlated significantly with overall survival. These findings suggest a need for improved education among surgeons and oncologists regarding the need lymph node assessment in pediatric oncology patients. Evidence rating/classification: Prognosis study, Level III.