A Novel Criterion for Lymph Nodes Dissection in Distal Pancreatectomy for Ductal Adenocarcinoma: A Population Study of the US SEER Database

Prognostic significance of three lymph node staging systems in pancreatic cancer with ≤ 12 and > 12 retrieved lymph nodes

This study aimed to evaluate and compare the predictive performance of negative lymph nodes (NLN), lymph node ratio (LNR), and N stage in pancreatic ductal adenocarcinoma (PDAC) among patients with ≤ 12 retrieved lymph nodes and those with > 12 retrieved lymph nodes. Moreover, the association between the three nodal staging systems and survival was also explored. Clinical data on patients diagnosed with PDAC between 2004 and 2020 were downloaded from the Surveillance, Epidemiology, and End Results (SEER) database. Cox regression was performed to identify independent predictors of cancer specific survival (CSS) and overall survival (OS). Survival probability was calculated and compared by the Kaplan-Meier method and log rank test. Akaike information criterion (AIC) and Harrell's C-index were used to evaluate the prognostic ability of each nodal staging system. All three lymph node staging systems were independent predictors of CSS and OS. A higher NLN, a lower N stage, and a lower LNR were associated with improved survival. Compared with N stage, LNR staging performed better with a lower AIC and higher C-index for predicting the prognosis regardless of the sufficiency of retrieved lymph nodes, while NLN staging performed poorly in both the training and validation set. Subgroup analyses showed that the NLN successfully predicted survival outcomes in both lymph node-positive and node-negative patients. LNR demonstrated better predictive performance in PDAC patients regardless of the sufficiency of retrieved lymph nodes. Notably, for stage N0 disease, NLN was a more important prognostic predictor. The combination of LNR and NLN may offer more precise information on lymph node staging than the current staging system.

The minimal number of examined lymph nodes for accurate nodal staging and favorable prognosis in T1-2 supraglottic laryngeal squamous cell carcinoma

OBJECTIVE

The study aimed to investigate the minimal number of examined lymph nodes (ELNs) for accurate assessment of lymph node status and favorable prognosis in patients with stage T1-2 supraglottic laryngeal squamous cell carcinoma (LSCC) who received radical resection.

METHODS

Patients with stage T1-2 supraglottic LSCC from the Surveillance, Epidemiology, and End Results (SEER) database and the Chinese Academy of Medical Sciences, Cancer Hospital/National Cancer Center (NCC) were reviewed. The association of the ELN count with the identification of nodal metastasis and overall survival (OS) was analyzed using a multivariate regression model. Locally weighted scatterplot smoothing fitting curve and the 'changepoint' package were adopted to identify the optimal cut points using R.

RESULTS

A total of 429 patients from the SEER database and 53 patients from NCC were enrolled. The probability of identifying nodal metastasis was positively related to the ELN count. For patients diagnosed with pathological stage N0 (pN0) disease, the mortality risks rapidly decreased when the amount of ELNs exceeded ten, and those with ELNs >10 had better OS.

CONCLUSION

An adequate amount of ELNs benefits precise nodal staging in patients with stage T1-2 supraglottic LSCC. Ten lymph nodes are the minimum number of ELNs. For pN0 patients, an ELN count ≤10 is an unfavorable prognostic factor.

Minimally invasive versus open distal pancreatectomy for resectable pancreatic cancer (DIPLOMA): an international randomised non-inferiority trial

BACKGROUND

The oncological safety of minimally invasive surgery has been questioned for several abdominal cancers. Concerns also exist regarding the use of minimally invasive distal pancreatectomy (MIDP) in patients with resectable pancreatic cancer as randomised trials are lacking.

METHODS

In this international randomised non-inferiority trial, we recruited adults with resectable pancreatic cancer from 35 centres in 12 countries. Patients were randomly assigned to either MIDP (laparoscopic or robotic) or open distal pancreatectomy (ODP). Both patients and pathologists were blinded to the assigned approach. Primary endpoint was radical resection (R0, ≥1 mm free margin) in patients who had ultimately undergone resection. Analyses for the primary endpoint were by modified intention-to-treat, excluding patients with missing data on primary endpoint. The pre-defined non-inferiority margin of -7% was compared with the lower limit of the two-sided 90% confidence interval (CI) of absolute difference in the primary endpoint. This trial is registered with the ISRCTN registry (ISRCTN44897265).

FINDINGS

Between May 8, 2018 and May 7, 2021, 258 patients were randomly assigned to MIDP (131 patients) or ODP (127 patients). Modified intention-to-treat analysis included 114 patients in the MIDP group and 110 patients in the ODP group. An R0 resection occurred in 83 (73%) patients in the MIDP group and in 76 (69%) patients in the ODP group (difference 3.7%, 90% CI -6.2 to 13.6%; pnon-inferiority = 0.039). Median lymph node yield was comparable (22.0 [16.0-30.0] vs 23.0 [14.0-32.0] nodes, p = 0.86), as was the rate of intraperitoneal recurrence (41% vs 38%, p = 0.45). Median follow-up was 23.5 (interquartile range 17.0-30.0) months. Other postoperative outcomes were comparable, including median time to functional recovery (5 [95% CI 4.5-5.5] vs 5 [95% CI 4.7-5.3] days; p = 0.22) and overall survival (HR 0.99, 95% CI 0.67-1.46, p = 0.94). Serious adverse events were reported in 23 (18%) of 131 patients in the MIDP group vs 28 (22%) of 127 patients in the ODP group.

INTERPRETATION

This trial provides evidence on the non-inferiority of MIDP compared to ODP regarding radical resection rates in patients with resectable pancreatic cancer. The present findings support the applicability of minimally invasive surgery in patients with resectable left-sided pancreatic cancer.

FUNDING

Medtronic Covidien AG, Johnson & Johnson Medical Limited, Dutch Gastroenterology Society.

The optimal number of examined lymph nodes for accurate nodal staging and favorable prognosis of oral tongue squamous cell carcinoma

OBJECTIVE

The study aimed to determine the optimal count of examined lymph nodes (ELN) for accurate assessment of lymph node status and favorable long-term survival in patients with oral tongue squamous cell carcinoma (OTSCC) who received radical resection.

METHODS

Patients with OTSCC who received radical resection between 2004 and 2015 were enrolled from the Surveillance, Epidemiology, and End Results database (SEER) and were randomly divided into two cohorts. The association of ELN count with nodal migration and overall survival (OS) was analyzed using a multivariate regression model with the adjustment of relevant factors. Locally weighted scatterplot smoothing (LOWESS) and 'strucchange' package were adopted to identify the optimal cut points using R.

RESULTS

A total of 2077 patients were included in this study. The optimal cut points of ELN count for accurate nodal staging and favorable OS were 19 and 15, respectively. The probability of detecting positive lymph nodes (PLN) significantly increased in patients with ELN count ≥ 19 in comparison to those with ELN count < 19 (training set, P < 0.001; validation set, P = 0.012). A better postoperative prognosis was observed in patients with ELN count ≥ 15 than those with fewer ELN (training set, P = 0.001, OR: 0.765; validation set, P = 0.016, OR: 0.678).

CONCLUSION

The optimal cut point of ELN count to ensure the accuracy of nodal staging and to achieve a favorable postoperative prognosis were 19 and 15, respectively. The ELN count beyond the cutoff values might improve the accuracy of cancer staging and OS.