In keeping with its mission to improve the quality of surgical care of patients with cancer, the ACS Cancer Research Program (CRP) published Volume 1 of the Operative Standards for Cancer Surgery in 2015.
Starting in 2021, the ACS Commission on Cancer (CoC) added operative standards into CoC accreditation standards and included them as a part of program accreditation, ensuring that accredited centers were performing high-quality cancer operations and were documenting this care through synoptic operative reporting and/or synoptic pathology reporting based on the standard.
Standard 5.8 focuses on lung cancer and requires patients undergoing curative resection for non-small cell lung cancer (NSCLC) to have at least 3 mediastinal (N2) lymph node stations and at least 1 hilar (N1) lymph node station assessed.1 For a site to be compliant, 80% of curative resections must meet this standard.
Previously, lymph node assessment in lung cancer surgery was tracked as a quality measure of assessing more than 10 lymph nodes, rather than as a standard used in accreditation. The inclusion of lymph node assessment during pulmonary resection as an accreditation standard reflects the continual, iterative review of research on the importance of nodal assessment and its impact on cancer-specific outcomes.
This focus on ongoing inquiry and evaluation of cancer care based on new knowledge and emerging research is at the heart of the ACS CRP. The ACS CRP Standards Investigation and Validation Committee is tasked with assessing current standards and conducting research that underpins ongoing standard evaluations and modifications.
Specialty Society Collaboration
Assessing national adherence and outcomes associated with Standard 5.8 via the National Cancer Database is challenging, as it does not capture the granular station-specific data needed to assess standard adherence.
However, since 2021, The Society of Thoracic Surgeons General Thoracic Surgery Database (STS-GTSD) has collected detailed data on lymph node stations, along with validated, risk-adjusted short-term outcomes. Building on the strengths of both organizations, a collaboration between the ACS CRP and STS led to three podium presentations at the STS 62nd Annual Meeting in January 2026.
National Assessment of Standard 5.8
The primary focus of the research was Standard 5.8 with respect to both national uptake and outcomes.2 We assessed the uptake of the standard at three levels:
- The resection level: How many actual resections met the standard and how did that change over time?
- The surgeon level: What percentage of surgeons, in any given year, had at least 80% of their resections meet the standard?
- The institution level: How many STS institutions, in any given year, had at least 80% of the resections performed meet the standard?
We found that adherence improved significantly over the study period (2021-2024) across all three metrics.
Overall, 66% of resections met the standard, improving from 54% in 2021 to nearly 75% by 2024. A primary factor associated with meeting the standard was the extent of resection. Patients who had an anatomic lung resection (i.e., lobectomy or segmentectomy) were more likely to have a resection that met the standard than patients who underwent a wedge resection.
At the surgeon and institution levels, adherence was low but improved significantly over the study period. In 2021, only 19% of institutions and 23% of surgeons would have met the current compliance threshold under the current standard. This improved to 43% of institutions and 44% of surgeons by 2024. This is an improvement, but it still falls well short of where we need to be.
As the primary benefit of lymph node assessment in lung cancer resection is improved pathologic staging, we assessed the oncologic impact of the Standard by measuring the rate of pathologic nodal upstaging.
Resections that met Standard 5.8, compared with those that did not, were associated with a 19% increase in nodal upstaging and had significantly more lymph nodes sampled (13.7 versus 8.5). There was no increase in operative morbidity or mortality overall, or in specific complications that would be directly associated with lymphadenectomy, such as chylothorax and recurrent laryngeal nerve injury.
The STS-GTSD also tracks several quality metrics and quality surrogates, notably surgeon volume and center observed-to-expected (O:E) operative mortality. Resections that met the standard were more likely to be performed by the highest volume surgeons and at centers that had the best O:E mortality ratio, showing a strong correlation between higher quality surgery and increased adherence to Standard 5.8.
This study is one of the first to validate the impact of Standard 5.8 using national-level data and further supports earlier studies highlighting the importance of standards in lung cancer surgery and adequate lymph node assessment in general.
Evaluating Nodal Assessment Strategies
The second study to come out of this collaboration expanded the analysis to three additional assessment standards.3 Two of the standards were lobe-specific (modified existing standards), and one was a hypothetical “2+1” strategy of only two mediastinal and one hilar lymph node stations.
We found that upstaging was broadly similar across the guidelines at around 11%, including the less rigorous “2+1” guideline, but that for resections that met none of the guidelines, the nodal upstaging rate was only 7.6%. This work further highlights the importance of having a nodal assessment standard to help ensure high-quality cancer surgery.
The papers presented represent the end product of months of discussion and collaboration between the primary investigators, all of whom were surgeons, and the biostatistical team at the STS Data Analytics Center.
Born out of those discussions was the question of whether we could use the granularity and power of the database to work backward. In other words, instead of looking at established guidelines and assessing their outcomes, could we look at the outcomes (i.e., nodal upstaging) and identify the strategy that optimized that outcome? This question, perhaps the most impactful, led to the third paper and was presented at the plenary session.4
Using the STS-GTSD, we analyzed approximately 50,000 clinically node-negative patients who underwent resection for NSCLC. We assessed the rate of nodal upstaging, stratified by the extent of N1 and N2 lymph node assessment, and found that the majority of upstaging was driven by an increase in N1 stations, rather than N2 stations, assessed and that the optimal strategy to maximize upstaging and minimize morbidity was one that increased the number of N1 stations examined.
For example, within this cohort of clinical N0 patients, resections that met Standard 5.8, but had only a single N1 station assessed, had an upstaging rate of 7.3%. For patients who had three N2 stations assessed but at least three N1 stations assessed, the upstaging rate more than doubled to 15.5%.
This study also assessed the impact on survival through linkage with the National Death Index and Medicare inpatient records. Among patients with pathologic node-negative disease, increasing N1 lymph node station assessment, and in particular intrapulmonary nodal station assessment, was associated with significantly improved survival.
Patients who had at least three N1 stations sampled had a 37% lower risk of death compared with patients who had no N1 lymph nodes assessed, a notable difference, especially considering median follow-up was less than 2 years.
Where Do We Go from Here?
Taken together, this work strengthens the data supporting the use of standards in lung cancer surgery and lymph node assessment in particular.
Standard 5.8, the only lung cancer standard tied to program accreditation, was associated with improved nodal upstaging, correlated with other surgical quality surrogates, and was not associated with any operative morbidity or mortality.
This work also highlights the power of collaboration between societies and paves the way for ongoing work to improve our standards through such collaboration. Just as the prior quality improvement measure of assessing at least 10 lymph nodes gave way to Standard 5.8, iterative processes to review and adapt our current standards will invariably lead to continuous improvement and adoption of standards that improve the care of patients with cancer.
These findings suggest that further improvements in the surgical care of patients with lung cancer may depend on more comprehensive N1 lymph node assessment in order to optimize staging and guide the delivery of ever-evolving systemic therapies.
The work of the ACS CRP and the Standards Investigation and Validation Committee is focused on helping investigators in this process and will continue to facilitate efforts and collaborations such as this, with the ultimate goal of providing the best care possible for patients with cancer.
Dr. Seth Krantz is chief of thoracic surgery at Endeavor Health in Evanston, Illinois, and a clinical associate professor of surgery at The University of Chicago. He is a member of the ACS CRP Standards Investigation and Validation Committee. His research focuses on quality outcomes in lung cancer surgery and on better understanding genetic risk in lung cancer.
References
- Nissen AP, Vreeland TJ, Teshome M, et al. American College of Surgeons Commission on Cancer standard for curative-intent pulmonary resection. Ann Thorac Surg. 2022;113(1):5–8.
- Krantz SB, et al. National assessment of adherence to Commission on Cancer Standard 5.8 and its impact on nodal upstaging rates and operative morbidity. Ann Thorac Surg. Published online September 10, 2026.
- Potter AL, Wang D, Bonnell L, et al. Comparing nodal upstaging rates and morbidity and mortality of common nodal sampling guidelines in the STS General Thoracic Surgery Database. Ann Thorac Surg. 2026;121(6):1309–1317.
- Seder CW, et al. Association between N1 nodal assessment, upstaging, and survival in resected non-small cell lung cancer. Ann Thorac Surg. Published online September 18, 2026.
