High-Risk Features Associated with Recurrence in Stage I Lung Adenocarcinoma

OBJECTIVE

There is a lack of knowledge regarding the use of prognostic features in stage I lung adenocarcinoma (LUAD). Thus, we investigated clinicopathologic features associated with recurrence after complete resection for stage I LUAD.

METHODS

We performed a retrospective analysis of patients with pathologic stage I LUAD who underwent R0 resection from 2010 to 2020. Exclusion criteria included history of lung cancer, induction or adjuvant therapy, noninvasive or mucinous LUAD, and death within 90 days of surgery. Fine and Gray competing-risk regression assessed associations between clinicopathologic features and disease recurrence.

RESULTS

In total, 1912 patients met inclusion criteria. Most patients (1565 [82%]) had stage IA LUAD, and 250 developed recurrence: 141 (56%) distant and 109 (44%) locoregional only. The 5-year cumulative incidence of recurrence was 12% (95% confidence interval, 11%-14%). Higher maximum standardized uptake value of the primary tumor (hazard ratio [HR]=1.04), sublobar resection (HR=2.04), higher IASLC grade (HR=5.32 [grade 2]; HR=7.93 [grade 3]), lymphovascular invasion (HR=1.70), visceral pleural invasion (HR=1.54), and tumor size (HR=1.30) were independently associated with hazard of recurrence. Tumors with 3-4 high-risk features had a higher cumulative incidence of recurrence at 5 years than tumors without these features (30% vs. 4%; p<0.001).

CONCLUSIONS

Recurrence after resection for stage I LUAD remains an issue for select patients. Commonly reported clinicopathologic features can be used to define patients at high risk of recurrence and should be considered when assessing the prognosis of patients with stage I disease.

A real-world assessment of stage I lung cancer through electronic nose technology

INTRODUCTION

Electronic nose (E-nose) technology has demonstrated excellent sensitivity and specificity in the setting of lung cancer screening. However, the performance of E-nose specifically for early-stage tumors remains unclear. Therefore, the aim of our study was to assess the diagnostic performance of E-nose technology in clinical stage I lung cancer.

METHODS

This Phase-IIc trial (NCT04734145) included patients diagnosed with a single ≥50% solid stage I nodule. Exhalates were prospectively collected from January 2020 to August 2023. Blinded bioengineers analyzed the exhalates, using E-nose technology to determine the probability of malignancy. Patients were stratified into 3 risk groups (low-risk, <0.2; moderate-risk, ≥0.2 to 0.7; high-risk, ≥0.7). The primary outcome was the diagnostic performance of E-nose versus histopathology (accuracy and F1 score). The secondary outcome was the clinical performance of the E-nose versus clinicoradiological prediction models.

RESULTS

Based on the predefined cut-off (<0.20), E-nose agreed with histopathological results in 86% of cases, achieving an F1 score of 92.5%, based on 86 true positives, 2 false negatives, and 12 false positives (n=100). Compared with Swensen and Brock models, E-nose would refer fewer patients with malignant nodules to observation (Low-risk: 2 vs. 9 and 11; respectively; p=0.028 and p=0.011) and more patients with malignant nodules to treatment without biopsy (High-risk: 27 vs. 19 and 6; respectively; p=0.057 and p<0.001).

CONCLUSIONS

In the setting of clinical stage I lung cancer, E-nose has good agreement with histopathology. Accordingly, E-nose technology can be used in addition to imaging or as part of a "multiomics" platform.

The Emerging Role of Immunotherapy in Resectable Non-Small Cell Lung Cancer

BACKGROUND

Despite surgical resection, long-term survival of patients with resectable non-small cell lung cancer (NSCLC) remains poor. Adjuvant chemotherapy, the standard of care for locally advanced NSCLC, provides a marginal 5.4% benefit in survival. Immune checkpoint inhibitors (ICIs) have shown a significant survival benefit in some patients with advanced NSCLC and are being evaluated for perioperative use in resectable NSCLC.

METHODS

We conducted a literature search using the PubMed online database to identify clinical trials of immunotherapy in resectable NSCLC and studies analyzing biomarkers and immune priming strategies.

RESULTS

Building on previous phase I and II trials, randomized phase III trials have shown efficacy of neoadjuvant nivolumab, perioperative pembrolizumab, adjuvant atezolizumab, and adjuvant pembrolizumab in the treatment of NSCLC with improvement of event-free/disease-free survival of 24% to 42%, leading to United States Food and Drug Administration approval of these drugs in the treatment of resectable NSCLC. Three additional phase III trials have also recently reported the use of immunotherapy both before and after surgery, with pathologic complete response rates of 17% to 25%, significantly better than chemotherapy alone. Perioperative ICI therapy has comparable perioperative morbidity to chemotherapy alone and does not impair surgical outcomes.

CONCLUSIONS

Perioperative immunotherapy, in combination with chemotherapy, is safe and improves outcomes in patients with resectable NSCLC. Questions regarding patient selection, the need for adjuvant ICI therapy after neoadjuvant chemoimmunotherapy, and the duration of perioperative immunotherapy remain to be answered by future trials.

Operative Time is Associated With Postoperative Complications After Pulmonary Lobectomy

OBJECTIVE

To investigate the association between operative time and postoperative outcomes.

BACKGROUND

The association between operative time and morbidity after pulmonary lobectomy has not been characterized fully.

METHODS

Patients who underwent pulmonary lobectomy for primary lung cancer at our institution from 2010 to 2018 were reviewed. Exclusion criteria included clinical stage ≥IIb disease, conversion to thoracotomy, and previous ipsilateral lung treatment. Operative time was measured from incision to closure. Relationships between operative time and outcomes were quantified using multivariable mixed-effects models with surgeon-level random effects.

RESULTS

In total, 1651 patients were included. The median age was 68 years (interquartile range, 61-74), and 63% of patients were women. Median operative time was 3.2 hours (interquartile range, 2.7-3.8) for all cases, 3.0 hours for open procedures, 3.3 hours for video-assisted thoracoscopies, and 3.3 hours for robotic procedures ( P =0.0002). Overall, 488 patients (30%) experienced a complication; 77 patients (5%) had a major complication (grade ≥3), and 5 patients (0.3%) died within 30 days of discharge. On multivariable analysis, operative time was associated with higher odds of any complication [odds ratio per hour, 1.37; 95% confidence interval (CI), 1.20-1.57; P <0.0001] and major complication (odds ratio per hour, 1.41; 95% CI, 1.21-1.64; P <0.0001). Operative time was also associated with longer hospital length of stay (β, 1.09; 95% CI, 1.04-1.14; P =0.001).

CONCLUSIONS

Longer operative time was associated with worse outcomes in patients who underwent lobectomy. Operative time is a potential risk factor to consider in the perioperative phase.

Superior sulcus non-small cell lung cancers (Pancoast tumors): Current outcomes after multidisciplinary management

OBJECTIVE

Despite neoadjuvant chemoradiotherapy, Pancoast tumors still present surgical and oncologic challenges. To optimize outcomes, we used a multidisciplinary care paradigm with medical and radiation oncology, and involvement of spine neurosurgery for most T3 and all T4 tumors. Spine neurosurgery permitted resection of transverse process for T3 and vertebral body resection for T4 tumors.

METHODS

Retrospective analysis of single institution, prospective database of patients undergoing resection for cT3 4M0 Pancoast tumors. Patients were grouped as cT3 with combined resection with spine neurosurgery (T3 Neuro), cT3 without spine neurosurgery (T3 NoNeuro), and cT4. Overall survival, progression-free survival were analyzed by Kaplan-Meier and compared between groups using log-rank test. Cumulative incidence of local-regional and distant recurrence were compared using Gray test. P value <.05 was considered significant.

RESULTS

From 2000 to 2021, 155 patients underwent surgery: median age was 58 years, and 81 were (52%) men. Most patients received neoadjuvant platinum-based neoadjuvant chemoradiotherapy (n = 127 [82%]). Operations were 48 cT3 Neuro, 41 cT3 NoNeuro, 66 cT4. R0 resection was achieved in 49 (94%) cT3 NoNeuro, 35 (85%) cT3 Neuro, and 57 (86%) cT4 patients (P = .4). Complete or major pathologic response occurred in 71 (55%) patients. Lower local-regional cumulative incidence was seen in cT3 Neuro versus cT3 NoNeuro (P = .05) and after major pathologic response. Overall survival and progression-free survival were associated with complete response, pathologic stage, and nodal status but not cT category.

CONCLUSIONS

This treatment paradigm was associated with a high frequency of R0 resection, complete response, and major pathologic response. cT3 and cT4 tumors had similar outcomes. Novel therapies are needed to improve complete response.

Biologic versus synthetic prosthesis for chest wall reconstruction: a matched analysis

OBJECTIVES

The aim of this study was to compare postoperative outcomes between biologic and synthetic reconstructions after chest wall resection in a matched cohort.

METHODS

All patients who underwent reconstruction after full-thickness chest wall resection from 2000 to 2022 were reviewed and stratified by prosthesis type (biologic or synthetic). Biologic prostheses were of biologic origin or were fully absorbable and incorporable. Integer matching was performed to reduce confounding. The study end point was surgical site complications requiring reoperation. Multivariable analysis was performed to identify associated risk factors.

RESULTS

In total, 438 patients underwent prosthetic chest wall reconstruction (unmatched: biologic, n = 49; synthetic, n = 389; matched: biologic, n = 46; synthetic, n = 46). After matching, the median (interquartile range) defect size was 83 cm2 (50-142) for the biologic group and 90 cm2 (48-146) for the synthetic group (P = 0.97). Myocutaneous flaps were used in 33% of biologic reconstructions (n = 15) and 33% of synthetic reconstructions (n = 15) in the matched cohort (P = 0.99). The incidence of surgical site complications requiring reoperation was not significantly different between biologic and synthetic reconstructions in the unmatched (3 [6%] vs 29 [7%]; P = 0.99) and matched (2 [4%] vs 4 [9%]; P = 0.68) cohorts. On the multivariable analysis, operative time [adjusted odds ratio (aOR) = 1.01, 95% confidence interval (CI), 1.00-1.01; P = 0.006] and operative blood loss (aOR = 1.00, 95% CI, 1.00-1.00]; P = 0.012) were associated with higher rates of surgical site complications requiring reoperation; microvascular free flaps (aOR = 0.03, 95% CI, 0.00-0.42; P = 0.024) were associated with lower rates.

CONCLUSIONS

The incidence of surgical site complications requiring reoperation was not significantly different between biologic and synthetic prostheses in chest wall reconstructions.

Lung resection after initial nonoperative treatment for non-small cell lung cancer

OBJECTIVES

The study objectives were to assess the outcomes of lung resection in patients with non-small cell lung cancer previously treated with nonoperative treatment and to identify prognostic factors associated with survival.

METHODS

Patients who underwent surgery (2010-2022) after initial nonoperative treatment at a single institution were identified from a prospectively maintained database. Exclusion criteria included metachronous cancer, planned neoadjuvant therapy, and surgery for diagnostic or palliative indications. Cox models were constructed for overall survival and event-free survival. Survival of patients with stage IV disease was compared with survival of a nonstudy cohort who did not undergo surgery.

RESULTS

In total, 120 patients met the inclusion criteria. Initial clinical stage was early stage in 16%, locoregionally advanced in 25%, and metastatic in 59% of patients. The indication for surgery was recurrence in 18%, local persistent disease in 23%, oligoprogression in 22%, and local control of oligometastatic disease in 38% of patients. Grade 3 or greater complications occurred in 5% of patients; 90-day mortality was 3%. Three-year event-free survival and overall survival were 39% and 73%, respectively. Male sex and lymphovascular invasion were associated with shorter event-free survival and overall survival; younger age and prior radiation therapy were associated with shorter overall survival. Patients with stage IV disease who received salvage lung resection had better overall survival than similar patients who received subsequent systemic therapy and no surgery.

CONCLUSIONS

In this selected, heterogeneous population, lung resection after initial nonoperative treatment for non-small cell lung cancer was safe. Surgery as local consolidative therapy was associated with encouraging outcomes and should be considered for these patients.

Prognostic value of circumferential radial margin involvement in esophagectomy for esophageal cancer: a case series

BACKGROUND

Residual tumor at the proximal or distal margin after esophagectomy is associated with worse survival outcomes; however, the significance of the circumferential resection margin (CRM) remains controversial. In this study, we sought to evaluate the prognostic significance of the CRM in patients with esophageal cancer undergoing resection.

MATERIALS AND METHODS

We identified patients who underwent esophagectomy for pathologic T3 esophageal cancer from 2000 to 2019. Patients were divided into three groups: CRM- (residual tumor >1 mm from the CRM), CRM-close (residual tumor >0 to 1 mm from the CRM), and CRM+ (residual tumor at the surgical CRM). CRM was also categorized and analyzed per the Royal College of Pathologists (RCP) and College of American Pathologists (CAP) classifications.

RESULTS

Of the 519 patients included, 351 (68%) had CRM-, 132 (25%) had CRM-close, and 36 (7%) had CRM+. CRM+ was associated with shorter disease-free survival [DFS; CRM+ vs. CRM-: hazard ratio (HR), 1.53 [95% CI, 1.03-2.28]; P =0.034] and overall survival (OS; CRM+ vs. CRM-: HR, 1.97 [95% CI, 1.32-2.95]; P <0.001). Survival was not significantly different between CRM-close and CRM-. After adjustment for potential confounders, CAP+ was associated with poor oncologic outcomes (CAP+ vs. CAP-: DFS: HR, 1.47 [95% CI, 1.00-2.17]; P =0.050; OS: HR, 1.93 [95% CI, 1.30-2.86]; P =0.001); RCP+ was not (RCP+ vs. RCP-: DFS: HR, 1.21 [95% CI, 0.97-1.52]; P =0.10; OS: HR, 1.21 [95% CI, 0.96-1.54]; P =0.11).

CONCLUSION

CRM status has critical prognostic significance for patients undergoing esophagectomy: CRM+ was associated with worse outcomes, and outcomes between CRM-close and CRM- were similar.

The Thoracic Research Evaluation and Treatment 2.0 Model: A Lung Cancer Prediction Model for Indeterminate Nodules Referred for Specialist Evaluation

BACKGROUND

Appropriate risk stratification of indeterminate pulmonary nodules (IPNs) is necessary to direct diagnostic evaluation. Currently available models were developed in populations with lower cancer prevalence than that seen in thoracic surgery and pulmonology clinics and usually do not allow for missing data. We updated and expanded the Thoracic Research Evaluation and Treatment (TREAT) model into a more generalized, robust approach for lung cancer prediction in patients referred for specialty evaluation.

RESEARCH QUESTION

Can clinic-level differences in nodule evaluation be incorporated to improve lung cancer prediction accuracy in patients seeking immediate specialty evaluation compared with currently available models?

STUDY DESIGN AND METHODS

Clinical and radiographic data on patients with IPNs from six sites (N = 1,401) were collected retrospectively and divided into groups by clinical setting: pulmonary nodule clinic (n = 374; cancer prevalence, 42%), outpatient thoracic surgery clinic (n = 553; cancer prevalence, 73%), or inpatient surgical resection (n = 474; cancer prevalence, 90%). A new prediction model was developed using a missing data-driven pattern submodel approach. Discrimination and calibration were estimated with cross-validation and were compared with the original TREAT, Mayo Clinic, Herder, and Brock models. Reclassification was assessed with bias-corrected clinical net reclassification index and reclassification plots.

RESULTS

Two-thirds of patients had missing data; nodule growth and fluorodeoxyglucose-PET scan avidity were missing most frequently. The TREAT version 2.0 mean area under the receiver operating characteristic curve across missingness patterns was 0.85 compared with that of the original TREAT (0.80), Herder (0.73), Mayo Clinic (0.72), and Brock (0.68) models with improved calibration. The bias-corrected clinical net reclassification index was 0.23.

INTERPRETATION

The TREAT 2.0 model is more accurate and better calibrated for predicting lung cancer in high-risk IPNs than the Mayo, Herder, or Brock models. Nodule calculators such as TREAT 2.0 that account for varied lung cancer prevalence and that consider missing data may provide more accurate risk stratification for patients seeking evaluation at specialty nodule evaluation clinics.

The contribution of microvascular free flaps and pedicled flaps to successful chest wall surgery

OBJECTIVE

Pedicled flaps (PFs) have historically served as the preferred option for reconstruction of large chest wall defects. More recently, the indications for microvascular-free flaps (MVFFs) have increased, particularly for defects in which PFs are inadequate or unavailable. We sought to compare oncologic and surgical outcomes between MVFFs and PFs in reconstructions of full-thickness chest wall defects.

METHODS

We retrospectively identified all patients who underwent chest wall resection at our institution from 2000 to 2022. Patients were stratified by flap reconstruction. End points were defect size, rate of complete resection, rate of local recurrence, and postoperative outcomes. Multivariable analysis was performed to identify factors associated with complications at 30 days.

RESULTS

In total, 536 patients underwent chest wall resection, of whom 133 had flap reconstruction (MVFF, n = 28; PF, n = 105). The median (interquartile range) covered defect size was 172 cm2 (100-216 cm2) for patients receiving MVFF versus 109 cm2 (75-148 cm2) for patients receiving PF (P = .004). The rate of R0 resection was high in both groups (MVFF, 93% [n = 26]; PF, 86% [n = 90]; P = .5). The rate of local recurrence was 4% in MVFF patients (n = 1) versus 12% in PF patients (n = 13, P = .3). Postoperative complications were not statistically different between groups (odds ratio for PF, 1.37; 95% confidence interval, 0.39-5.14]; P = .6). Operative time >400 minutes was associated with 30-day complications (odds ratio, 3.22; 95% confidence interval, 1.10-9.93; P = .033).

CONCLUSIONS

Patients with MVFFs had larger defects, a high rate of complete resection, and a low rate of local recurrence. MVFFs are a valid option for chest wall reconstructions.

ctDNA-based detection of molecular residual disease in stage I-III non-small cell lung cancer patients treated with definitive radiotherapy

Background

Sensitive and reliable biomarkers for early detection of recurrence are needed to improve post-definitive radiation risk stratification, disease management, and outcomes for patients with unresectable early-stage or locally advanced non-small cell lung cancer (NSCLC) who are treated with definitive radiation therapy (RT). This prospective, multistate single-center, cohort study investigated the association of circulating tumor DNA (ctDNA) status with recurrence in patients with unresectable stage I-III NSCLC who underwent definitive RT.

Methods

A total of 70 serial plasma samples from 17 NSCLC patients were collected before, during, and after treatment. A personalized, tumor-informed ctDNA assay was used to track a set of up to 16 somatic, single nucleotide variants in the associated patient's plasma samples.

Results

Pre-treatment ctDNA detection rate was 82% (14/17) and varied based on histology and stage. ctDNA was detected in 35% (6/17) of patients at the first post-RT timepoint (median of 1.66 months following the completion of RT), all of whom subsequently developed clinical progression. At this first post-RT time point, patients with ctDNA-positivity had significantly worse progression-free survival (PFS) [hazard ratio (HR): 24.2, p=0.004], and ctDNA-positivity was the only significant prognostic factor associated with PFS (HR: 13.4, p=0.02) in a multivariate analysis. All patients who developed clinical recurrence had detectable ctDNA with an average lead time over radiographic progression of 5.4 months, and post-RT ctDNA positivity was significantly associated with poor PFS (p<0.0001).

Conclusion

Personalized, longitudinal ctDNA monitoring can detect recurrence early in patients with unresectable NSCLC patients undergoing curative radiation and potentially risk-stratify patients who might benefit most from treatment intensification.

Translating Telemedicine to Thoracic Surgical Oncological Care: Performance Analysis and Patient Perceptions During the COVID-19 Pandemic

OBJECTIVE

The objective is to determine how the COVID-19 pandemic affected care for patients undergoing thoracic surgery for cancer.

BACKGROUND

The COVID-19 pandemic accelerated the adoption of telemedicine.

METHODS

Characteristics and outcomes of new patients seen between March 1 and June 30, 2019, and the same period in 2020 were compared. Patients who did not undergo surgery were excluded. Patients who had a telemedicine visit (new and established) in the 2020 period were asked to complete a survey.

RESULTS

In total, 624 new patients were seen in 2019 versus 299 in 2020 (52% reduction); 45% of patients (n=136) in 2020 were seen via telemedicine. There was no statistically significant difference in time to surgery, pathological upstaging, or postsurgical complications between 2019 and 2020. In total, 1085 patients (new and established) had a telemedicine visit in 2020; 239 (22%) completed the survey. A majority replied that telemedicine was equivalent to in-person care (77%), did not impair care quality (84%), resulted in less stress (69%) and shorter waits (86%), was more convenient (92%), saved money and commuting time (93%), and expanded who could attend visits (91%). Some patients regretted the loss of human interaction (71%). Most would opt for telemedicine after the pandemic (60%), although some would prefer in-person format for initial visits (55%) and visits with complex discussions (49%). Only 21% were uncomfortable with the telemedicine technology.

CONCLUSIONS

Telemedicine enabled cancer care to continue during the COVID-19 pandemic without delays in surgery, cancer progression, or worsened postoperative morbidity and was generally well received.

Clinicopathologic outcomes of preoperative targeted therapy in patients with clinical stage I to III non-small cell lung cancer

OBJECTIVE

Targeted therapy improves outcomes in patients with advanced-stage non-small cell lung cancer (NSCLC) and in the adjuvant setting, but data on its use before surgery are limited. We sought to investigate the safety and feasibility of preoperative targeted therapy in patients with operable NSCLC.

METHODS

We retrospectively reviewed 51 patients with clinical stage I to III NSCLC who received targeted therapy, alone or in combination with chemotherapy, before surgical resection with curative intent, treated from 2004 to 2021. The primary outcome was the safety and feasibility of preoperative targeted therapy; secondary outcomes included objective response rate, major pathologic response (defined as ≤10% viable tumor) rate, recurrence-free survival (RFS), and overall survival.

RESULTS

Of the 51 patients included, 46 had an activating epidermal growth factor receptor gene alteration and 5 had an anaplastic lymphoma kinase fusion. Overall, 37 of 46 evaluable patients experienced at least 1 adverse event before surgery; however, only 3 patients experienced a grade 3 or 4 event. The objective response rate was 38% (17/45) for all evaluable patients and 44% (14/32) for patients with clinical stage II or III disease. The major pathologic response rate was 20% (9/44); 2 patients had a complete pathologic response. Median RFS was 3.8 years (95% CI, 2.8 to not reached). Targeted therapy alone was associated with better RFS than combination therapy (P = .009) in patients with clinical stage II or III disease.

CONCLUSIONS

Preoperative targeted therapy was well tolerated and associated with good outcomes, with or without induction chemotherapy. In addition, radiographic response and pathologic response were strongly correlated.

Waiting to Operate: The Risk of Salvage Esophagectomy

OBJECTIVE

To assess postoperative morbidity, disease-free survival (DFS), and overall survival (OS) in patients treated with salvage esophagectomy (SE).

BACKGROUND DATA

A shift toward a "surgery as needed" approach for esophageal cancer has emerged, potentially resulting in delayed esophagectomy.

METHODS

We identified patients with clinical stage I-III esophageal adenocarcinoma or squamous cell carcinoma who underwent chemoradiation followed by esophagectomy from 2001 to 2019. SE was defined as esophagectomy performed >90 days after chemoradiation ("for time") and esophagectomy performed for recurrence after curative-intent chemoradiation ("for recurrence"). The odds of postoperative serious complications were assessed by multivariable logistic regression. The relationship between SE and OS and DFS were quantified using Cox regression models.

RESULTS

Of 1137 patients identified, 173 (15%) underwent SE. Of those, 61 (35%) underwent SE for recurrence, and 112 (65%) underwent SE for time. The odds of experiencing any serious complication [odds ratio, 2.10 (95% CI, 1.37-3.20); P =0.001] or serious pulmonary complication [odds ratio, 2.11 (95% CI, 1.31-3.42); P =0.002] were 2-fold higher for SE patients; SE patients had a 1.5-fold higher hazard of death [hazard ratio, 1.56 (95% CI, 1.25-1.94); P <0.0001] and postoperative recurrence [hazard ratio, 1.43 (95% CI, 1.16-1.77); P =0.001]. Five-year OS for nonsalvage esophagectomy was 45% [(95% CI, 41.6%-48.6%) versus 26.5% (95% CI, 20.2%-34.8%) for SE (log-rank P <0.001)]. Five-year OS for SE for time was 27.1% [(95% CI, 19.5%-37.5%) versus 25.2% (95% CI, 15.3%-41.5%) for SE for recurrence ( P =0.611)].

CONCLUSIONS

SE is associated with a higher risk of serious postoperative complications and shorter DFS and OS.

Abstract 3375: Ultrasensitive ctDNA minimal residual disease monitoring in early NSCLC with PhasED-Seq

Background: Circulating tumor DNA (ctDNA) minimal residual disease (MRD) detection is a promising approach for personalization of adjuvant therapy in non-small cell lung cancer (NSCLC). First generation ctDNA MRD assays that employ tumor-informed approaches to track single nucleotide variants (SNVs) have limits of detection (LOD95) of ~1E-4 and have high positive predictive values for recurrence. However, they have suboptimal clinical sensitivity, with false negative results at the completion of therapy in most patients who will ultimately recur. PhasED-Seq is a novel ctDNA MRD method that tracks multiple “phased” variants (PVs) within individual DNA fragments with a LOD95 ~100-fold better than first generation assays. Here we report PhasED-Seq ctDNA MRD results for the first prospective cohort of early stage NSCLC patients.

Methods: Tumor tissues (n=46), PBMCs (n=46) and plasma samples (n=169) from 46 Stage I-III NSCLC patients treated with curative intent were prospectively collected at Memorial Sloan Kettering Cancer Center. All patients underwent resection and received neoadjuvant +/- adjuvant therapy (n=14), adjuvant therapy only (n=17), or neither (n=15). Samples were analyzed in Foresight Diagnostics' CLIA laboratory (Aurora, CO) using personalized PhasED-Seq. Briefly, PVs were identified via whole genome sequencing of tumors and matched blood germline DNA. Custom capture panels targeting PVs were synthesized and used to assess MRD status in pre-, on- and post-treatment plasma samples. Detection of ctDNA MRD was assessed at a post-treatment landmark, defined as the first post-therapy sample or when not available the last post-surgical sample taken during therapy. To enable comparisons, the same plasma samples were analyzed using an SNV-based ctDNA MRD approach.

Results: PVs were identified in tumor tissue from all 46 patients. Across all plasma samples PhasED-Seq achieved a median LOD95 of 1.3E-6 and as low as 2.5E-7. Of 74 plasma samples with detectable ctDNA, 38 (51%) contained concentrations below 1E-4 and the lowest level of ctDNA MRD detected was 1.7E-7. For post-treatment landmark samples (n=45), the median time from end of therapy was 2 months. Cancer recurred in all patients (n=10) with detectable MRD at the landmark. Furthermore, PhasED-Seq better stratified freedom from recurrence (log-rank p=3E-8, Cox HR=10.8) than the SNV-based approach (log-rank p=0.08, Cox HR=2.5) and detected MRD at the landmark in more patients who ultimately recurred (56% vs 28%). PhasED-Seq also achieved longer lead times, including detecting MRD in 66% of samples collected 12 to 24 months prior to recurrence versus only 33% using SNV-based monitoring.

Conclusion: PhasED-Seq achieves ctDNA detection below 1 part per million and appears to be significantly more sensitive than SNV-based MRD monitoring. These results suggest that PhasED-Seq is a promising approach for use in risk adapted trials in early stage NSCLC.

Citation Format: James M. Isbell, Bob T. Li, Pedram Razavi, Jorge Reis-Filo, Si-Yang Liu, Pier Selenica, Prasad Adusumilli, Matthew Bott, David R. Jones, Valerie W. Rusch, Smita Sihag, Darren J. Buonocore, Justin Jee, Emily Lebow, Daniel Gomez, Andreas Rimner, Fernando C. Santini, Charles M. Rudin, Jordan E. Eichholz, Andres Martinez, Daphne Alerte, Gregory J. Hogan, Andre Schultz, Ronald P. Schuyler, Alanna Roff, Dustin Hite, Jacob J. Chabon, David M. Kurtz, Ash A. Alizadeh, Maximilian Diehn. Ultrasensitive ctDNA minimal residual disease monitoring in early NSCLC with PhasED-Seq [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3375.

Induction FOLFOX and PET-Directed Chemoradiation for Locally Advanced Esophageal Adenocarcinoma

OBJECTIVE

To compare the efficacy and safety of induction FOLFOX followed by PET-directed nCRT, induction CP followed by PET-directed nCRT, and nCRT with CP alone in patients with EAC.

SUMMARY OF BACKGROUND DATA

nCRT with CP is a standard treatment for locally advanced EAC. The results of cancer and leukemia group B 80803 support the use of induction chemotherapy followed by PET-directed chemo-radiation therapy.

METHODS

We retrospectively identified all patients with EAC who underwent the treatments above followed by esophagectomy. We assessed incidences of pathologic complete response (pCR), near-pCR (ypN0 with ≥90% response), and surgical complications between treatment groups using Fisher exact test and logistic regression; disease-free survival (DFS) and overall survival (OS) were estimated by the Kaplan-Meier method and evaluated using the log-rank test and extended Cox regression.

RESULTS

In total, 451 patients were included: 309 (69%) received induction chemotherapy before nCRT (FOLFOX, n = 70; CP, n = 239); 142 (31%) received nCRT with CP. Rates of pCR (33% vs. 16%, P = 0.004), near-pCR (57% vs. 33%, P < 0.001), and 2-year DFS (68% vs. 50%, P = 0.01) were higher in the induction FOLFOX group than in the induction CP group. Similarly, the rate of near-pCR (57% vs. 42%, P = 0.04) and 2-year DFS (68% vs. 44%, P < 0.001) were significantly higher in the FOLFOX group than in the no-induction group.

CONCLUSIONS

Induction FOLFOX followed by PET-directed nCRT may result in better histopathologic response rates and DFS than either induction CP plus PET-directed nCRT or nCRT with CP alone.

Improved Preoperative Risk Assessment Tools Are Needed to Guide Informed Decision Making before Esophagectomy

OBJECTIVE

We sought to evaluate the performance of 2 commonly used prediction models for postoperative morbidity in patients undergoing open and minimally invasive esophagectomy.

SUMMARY BACKGROUND DATA

Patients undergoing esophagectomy have a high risk of postoperative complications. Accurate risk assessment in this cohort is important for informed decision-making.

METHODS

We identified patients who underwent esophagectomy between January 2016 and June 2018 from our prospectively maintained database. Predicted morbidity was calculated using the American College of Surgeons National Surgical Quality Improvement Program Surgical Risk Calculator (SRC) and a 5-factor National Surgical Quality Improvement Programderived frailty index. Performance was evaluated using concordance index (C-index) and calibration curves.

RESULTS

In total, 240 consecutive patients were included for analysis. Most patients (85%) underwent Ivor Lewis esophagectomy. The observed overall complication rate was 39%; the observed serious complication rate was 33%.The SRC did not identify risk of complications in the entire cohort (C-index, 0.553), patients undergoing open esophagectomy (C-index, 0.569), or patients undergoing minimally invasive esophagectomy (C-index, 0.542); calibration curves showed general underestimation. Discrimination of the SRC was lowest for reoperation (C-index, 0.533) and highest for discharge to a facility other than home (C-index, 0.728). Similarly, the frailty index had C-index of 0.513 for discriminating any complication, 0.523 for serious complication, and 0.559 for readmission.

CONCLUSIONS

SRC and frailty index did not adequately predict complications after esophagectomy. Procedure-specific risk-assessment tools are needed to guide shared patient-physician decision-making in this high-risk population.

Overall survival with circulating tumor DNA-guided therapy in advanced non-small-cell lung cancer

Circulating tumor DNA (ctDNA) sequencing guides therapy decisions but has been studied mostly in small cohorts without sufficient follow-up to determine its influence on overall survival. We prospectively followed an international cohort of 1,127 patients with non-small-cell lung cancer and ctDNA-guided therapy. ctDNA detection was associated with shorter survival (hazard ratio (HR), 2.05; 95% confidence interval (CI), 1.74-2.42; P < 0.001) independently of clinicopathologic features and metabolic tumor volume. Among the 722 (64%) patients with detectable ctDNA, 255 (23%) matched to targeted therapy by ctDNA sequencing had longer survival than those not treated with targeted therapy (HR, 0.63; 95% CI, 0.52-0.76; P < 0.001). Genomic alterations in ctDNA not detected by time-matched tissue sequencing were found in 25% of the patients. These ctDNA-only alterations disproportionately featured subclonal drivers of resistance, including RICTOR and PIK3CA alterations, and were associated with short survival. Minimally invasive ctDNA profiling can identify heterogeneous drivers not captured in tissue sequencing and expand community access to life-prolonging therapy.

Tumor volume as a predictor of cell free DNA mutation detection in advanced non-small cell lung cancer

Background

Cell free DNA (cfDNA) is an exciting biomarker with applications across the cancer care continuum. Determinants of cfDNA shedding dynamics remain an active research area. We performed a detailed analysis of tumor volume and factors associated with detection of cfDNA mutations.

Methods

Patients with advanced non-small cell lung cancers (NSCLCs) were prospectively enrolled on a plasma biomarker protocol. Next generation sequencing (NGS) was performed using a validated, bias-corrected, hybrid-capture panel assay of lung cancer-associated genes. Volume of tumor in different subsites and total tumor volume were determined through manual volume delineation using PET/CT and brain magnetic resonance imaging (MRI) imaging. The primary endpoint was detection of cfDNA mutation; secondary endpoints were overall survival (OS) and variant allele frequency (VAF).

Results

There were 110 patients included, 78 of whom had at least one mutation detected. Median total tumor volume for the entire cohort, patients with mutation detected, and patients with no mutation detected were 66 mL (range, 2-1,383 mL), 76 mL (range, 5-1,383 mL), and 45 mL (range, 2-460 mL), respectively (P=0.002; mutation detected vs. not). The optimal total tumor volume threshold to predict increased probability of mutation detection was 65 mL (P=0.006). Total tumor volume greater than 65 mL was a significant predictor of mutation detection on multivariate analysis (OR: 4.30, P=0.003). Significant predictors of OS were age (HR: 1.04, P=0.002), detection of cfDNA mutation (HR: 2.11, P=0.024), and presence of bone metastases (HR: 1.66, P=0.047).

Conclusions

Total tumor volume greater than 65 mL was associated with cfDNA mutation detection in patients with advanced NSCLC.

Brief Report: Contralateral Lobectomy for Second Primary NSCLC: Perioperative and Long-Term Outcomes

Introduction

Anatomical resection-often by lobectomy-is the standard of care for patients with early stage NSCLC. With increased diagnosis, survival, and prevalence of persons with early stage NSCLC, the incidence of second primary NSCLC, and consequently, the need for contralateral lobectomy for a metachronous cancer, is increasing. Perioperative outcomes after contralateral lobectomy are unknown.

Methods

Among patients who underwent contralateral lobectomy for second primary NSCLC during 1995 to 2020, we evaluated 90-day mortality and major morbidity (Clavien-Dindo grades 3-5) rates and their association with clinicopathologic variables, including the year of contralateral lobectomy and duration between lobectomies.

Results

A total of 98 patients underwent contralateral lobectomy for second primary NSCLC; 51 during an early time period (1995-2009) and 47 from a late time period (2010-2020). There were five mortalities and 23 patients with major morbidities after contralateral lobectomy; both rates decreased in 2010 to 2020 compared with 1995 to 2009 (mortality 10%-0%, major morbidity 35%-11%). Major morbidity was associated with an interval of less than 1 year between lobectomies, a diffusing capacity of the lung for carbon monoxide <80%, and right lower lobe resections. Mortality was associated with squamous cell carcinoma. Patients who underwent contralateral lobectomy for stage I NSCLC had 74% (95% confidence interval: 64%-85%) 3-year overall survival and 15% (95% confidence interval: 6.5%-24%) 3-year lung cancer cumulative incidence of death.

Conclusions

Contralateral lobectomy for second primary early stage NSCLC was associated with poor outcomes before 2010. Since 2010, perioperative and long-term outcomes of contralateral lobectomy have been comparable with reported outcomes after unilateral lobectomy.

Minimal residual disease (MRD) detection by ctDNA in relation to radiographic disease progression in patients with stage I-III non–small cell lung cancer (NSCLC) treated with definitive radiation therapy

8540

Background: The standard of care for patients with inoperable early stage or locally advanced NSCLC is definitive stereotactic body radiotherapy (SBRT) or conventional radiation therapy (RT) with systemic therapy. Circulating tumor DNA (ctDNA) testing can be used for the assessment of MRD and predict risk of recurrence. Few studies have prospectively evaluated MRD detection and ctDNA dynamics specifically among patients with early or locally advanced NSCLC receiving definitive RT. Methods: In a prospective clinical cohort of patients with stage I-III NSCLC (n = 17), serial plasma samples (n = 70) were collected before and after SBRT as well as before, during, and after conventional RT with or without concurrent systemic therapy and adjuvant durvalumab. Patients were followed-up for a median of 29 months (range: 4 to 54 months) with the last serial plasma collected at a median of 5 months from completion of RT (range: 1 – 26 months). A personalized, tumor-informed multiplex PCR assay (Signatera™ bespoke mPCR NGS assay) was used for the detection and quantification of ctDNA and tracked 16 tumor variants among 16 patients and 15 tumor variants in one patient. This study evaluated the prognostic value of ctDNA, correlating MRD status with clinical outcomes, in addition to ctDNA clearance kinetics during RT. Results: Among 17 patients with early-stage and locally advanced NSCLC, baseline ctDNA was detected in 82% of patients (14/17). Clinical progression was confirmed radiographically for 53% (9/17). All events of clinical progression were detectable by ctDNA (sensitivity 100%, 0.63 – 1.0), with a median lead-time of 5.5 months for MRD detection compared to radiographic disease progression. Durable ctDNA clearance was observed in 29% (5/17) of patients, all of whom then remained recurrence-free until the end of follow-up (median 12 months; specificity 100%, 95% CI 0.6 – 1.0). Transient ctDNA clearance was observed in 3 patients, and recurrent ctDNA was detected before or at the time of disease progression in all 3. ctDNA status after treatment at a single time point and longitudinally were highly predictive of disease recurrence (p < 0.0001). Conclusions: ctDNA detection is feasible for patients with stage I-III NSCLC undergoing definitive chemoradiation. and can serve as a powerful predictive biomarker for disease recurrence. High baseline detection rate is essential for feasibility of a ctDNA-based MRD assay. Residual detectable ctDNA represents a powerful predictive tool to identify patients who might benefit from intensification of adjuvant therapy following definitive RT.

Clinical outcomes of immune checkpoint inhibitors in HER2-amplified non-small cell lung cancers

e21098

Background: HER2 (ERBB2) amplification is a distinct actionable oncogenic driver in 2-3% of non-small cell lung cancer (NSCLC). While HER2-targeted agents are now in development for lung cancers harboring HER2 mutations, the therapeutic landscape for patients with HER2 amplification is not well elucidated. Although immune checkpoint inhibitors (ICIs) alone or in combination with chemotherapy are widely used as treatment for NSCLC, little is known about the impact of ICIs in patients with HER2-amplified NSCLC. This study aimed to assess the efficacy of ICIs in this patient population. Methods: Patients with HER2-amplified NSCLC were identified from January 2014 to October 2021. HER2 amplification was detected by next generation sequencing (NGS) on the MSK-IMPACT platform. Clinicopathologic and molecular features, as well as response to therapy with ICIs were assessed. Patients were excluded if they harbored concurrent HER2 mutations, had localized disease, or received concurrent chemotherapy. Patient records were reviewed to evaluate overall survival (OS), progression free survival (PFS) and overall response rate (ORR). Results: Eighteen patients with metastatic HER2-amplified NSCLC who received ICI alone as first line treatment or subsequent therapy after progression met inclusion criteria. Histologic subtypes included adenocarcinoma (78%) and squamous cell carcinoma (22%). PD-L1 expression was available for 16 patients, with 69% having no expression of PD-L1. The median tumor mutation burden (TMB) was 9.2 mutations/Mb (range 3.0-35.4). The median OS was 11 months (95% CI: 4 to 37), with 6-month and 12-month survival being 67% (95% CI: 40% to 83%) and 49% (95% CI: 25% to 70%), respectively. Median PFS was 2 months (95% CI: 1 to 7). In the 15 patients that were assessed for response, the ORR was 0% (95% CI 0% to 19%), including 3 cases with PD-L1 expression of ≥ 50% and 9 cases with TMB ≥ 10 mutation/Mb. Conclusions: Patients with HER2-amplified NSCLC showed minimal response to immunotherapy, regardless of PD-L1 status and TMB. These findings underscore the importance of developing novel HER2-targeted agents for these patients with unmet medical need.

Propensity-matched Analysis Demonstrates Long-term Risk of Respiratory and Cardiac Mortality After Pneumonectomy Compared With Lobectomy for Lung Cancer

OBJECTIVE

We sought to quantify and characterize long-term consequences of pneumonectomy, with particular attention to nononcologic mortality.

SUMMARY OF BACKGROUND DATA

Pneumonectomy is associated with profound changes in cardiopulmonary physiology. Studies of long-term outcomes after pneumonectomy typically report generalized measures, such as disease-free and overall survival.

METHODS

Patients undergoing lobectomy or pneumonectomy for lung cancer at our institution from 2000 to 2018 were reviewed. Propensity-score matching was performed for 12 clinicopathologic factors. Ninety-day complications and deaths were compared. Five-year cumulative incidence of oncologic and nononcologic mortality were compared using competing risks approaches.

RESULTS

From 3339 lobectomy and 355 pneumonectomy patients identified, we derived 318 matched pairs. At 90 days, rates of overall complications were similar (46% for pneumonectomy vs 43% for lobectomy; P = 0.40), but rates of major complications (21% vs 13%; P = 0.005) and deaths (6.9% vs 1.9%; P = 0.002) were higher the pneumonectomy cohort. The cumulative incidence of oncologic mortality was not significantly different between cohorts (P = 0.9584). However, the cumulative incidence of nononcologic mortality was substantially higher in the pneumonectomy cohort for both date of surgery and 1-year landmark analyses (P < 0.0001 and P = 0.0002, respectively). Forty-five pneumonectomy patients (18%) died of nononcologic causes 1-5 years after surgery; pneumonia (n = 21) and myocardial infarction (n = 10) were the most common causes. In pneumonectomy patients, preexisting cardiac comorbidity and low diffusion capacity of the lungs for carbon monoxide were predictive of nononcologic mortality.

CONCLUSIONS

Compared to lobectomy, excess mortality after pneumonectomy extends beyond 1 year and is driven primarily by nononcologic causes. Pneumonectomy patients require lifelong monitoring and may benefit from expeditious assessment and intervention at the initial signs of illness.

Inferring gene expression from cell-free DNA fragmentation profiles

Profiling of circulating tumor DNA (ctDNA) in the bloodstream shows promise for noninvasive cancer detection. Chromatin fragmentation features have previously been explored to infer gene expression profiles from cell-free DNA (cfDNA), but current fragmentomic methods require high concentrations of tumor-derived DNA and provide limited resolution. Here we describe promoter fragmentation entropy as an epigenomic cfDNA feature that predicts RNA expression levels at individual genes. We developed 'epigenetic expression inference from cell-free DNA-sequencing' (EPIC-seq), a method that uses targeted sequencing of promoters of genes of interest. Profiling 329 blood samples from 201 patients with cancer and 87 healthy adults, we demonstrate classification of subtypes of lung carcinoma and diffuse large B cell lymphoma. Applying EPIC-seq to serial blood samples from patients treated with PD-(L)1 immune-checkpoint inhibitors, we show that gene expression profiles inferred by EPIC-seq are correlated with clinical response. Our results indicate that EPIC-seq could enable noninvasive, high-throughput tissue-of-origin characterization with diagnostic, prognostic and therapeutic potential.

Patterns and Impact of Nodal Metastases After Neoadjuvant Chemoradiation and R0 Resection in Esophageal Adenocarcinoma

OBJECTIVE

Little is known about the pattern of nodal metastases in patients with esophageal adenocarcinoma who have received neoadjuvant chemoradiation and undergone surgery. We sought to assess this pattern and evaluate its association with prognosis.

METHODS

All patients with esophageal adenocarcinoma who underwent neoadjuvant chemoradiation and R0 esophagectomy between 2010 and 2018 at our institution were included (n = 537). The primary objective was to evaluate the association of sites of lymph node metastases with disease-free survival. The number of nodal stations and individual sites of nodal metastases were evaluated first in univariable then in separate multivariable Cox regression models adjusted for clinical factors.

RESULTS

Of 537 patients, 193 (36%) had pathologic nodal metastases at the time of surgery; 153 (28%) had single-station disease, 32 (6.0%) had 2-station disease, and 8 (1.5%) had 3-station disease. The majority of patients with multiple positive nodal stations had positive nodes in the paraesophageal (93%) and/or left gastric stations (60%). Multivariable models controlling for clinical factors showed that an increasing number of positive nodal stations (hazard ratio, 1.59; 95% CI, 1.35-1.84; P < .01)-in particular, the subcarinal (hazard ratio, 2.78; 95% CI, 1.54-5.03; P < .01) and paraesophageal stations (hazard ratio, 2.0; 95% CI, 1.58-2.54; P < .01)-was associated with increased risk of recurrence.

CONCLUSIONS

One-third of patients who have undergone R0 resection for esophageal adenocarcinoma following induction chemoradiation therapy have metastatic lymph nodes. An increasing number of nodal stations, particularly paraesophageal and subcarinal metastases, were associated with increased risk of recurrence.

Tumor and Tumor-Associated Macrophage Programmed Death-Ligand 1 Expression Is Associated With Adjuvant Chemotherapy Benefit in Lung Adenocarcinoma

INTRODUCTION

Patients with stage II to III lung adenocarcinomas are treated with adjuvant chemotherapy (ACT) to target the premetastatic niche that persists after curative-intent resection. We hypothesized that the premetastatic niche is a scion of resected lung tumor microenvironment and that analysis of tumor microenvironment can stratify survival benefit from ACT.

METHODS

Using tumor and tumoral stroma from 475 treatment-naive patients with stage II to III lung adenocarcinomas, we constructed a tissue microarray and performed multiplex immunofluorescent staining for immune markers (programmed death-ligand 1 [PD-L1], tumor-associated macrophages [TAMs], and myeloid-derived suppressor cells) and derived myeloid-lymphoid ratio. The association between immune markers and survival was evaluated using Cox models adjusted for pathologic stage.

RESULTS

Patients with high PD-L1 expression on TAMs or tumor cells in resected tumors had improved survival with ACT (TAMs: hazard ratio [HR] = 1.79, 95% confidence interval [CI]: 1.12-2.85; tumor cells: HR = 3.02, 95% CI: 1.69-5.40). Among patients with high PD-L1 expression on TAMs alone or TAMs and tumor cells, ACT survival benefit is pronounced with high myeloid-lymphoid ratio (TAMs: HR = 3.87, 95% CI: 1.79-8.37; TAMs and tumor cells: HR = 2.19, 95% CI: 1.02-4.71) or with high stromal myeloid-derived suppressor cell ratio (TAMs: HR = 2.53, 95% CI: 1.29-4.96; TAMs and tumor cells: HR = 3.21, 95% CI: 1.23-8.35). Patients with low or no PD-L1 expression on TAMs or tumor cells had no survival benefit from ACT.

CONCLUSIONS

Our observation that PD-L1 expression on TAMs or tumor cells is associated with improved survival with ACT provides rationale for prospective investigation and developing chemoimmunotherapy strategies for patients with lung adenocarcinoma.

Postinduction therapy pulmonary function retesting is necessary before surgical resection for non–small cell lung cancer

OBJECTIVE

Pretreatment-predicted postoperative diffusing capacity of the lung for carbon monoxide (DLCO) has been associated with operative mortality in patients who receive induction therapy for resectable non-small cell lung cancer (NSCLC). It is unknown whether a reduction in pulmonary function after induction therapy and before surgery affects the risk of morbidity or mortality. We sought to determine the relationship between induction therapy and perioperative outcomes as a function of postinduction pulmonary status in patients who underwent surgical resection for NSCLC.

METHODS

We retrospectively reviewed data for 1001 patients with pathologic stage I, II, or III NSCLC who received induction therapy before lung resection. Pulmonary function was defined according to American College of Surgeons Oncology Group major criteria: DLCO ≥50% = normal; DLCO <50% = impaired. Patients were categorized into 5 subgroups according to combined pre- and postinduction DLCO status: normal-normal, normal-impaired, impaired-normal, impaired-impaired, and preinduction only (without postinduction pulmonary function test measurements). Multivariable logistic regression was used to quantify the relationship between DLCO categories and dichotomous end points.

RESULTS

In multivariable analysis, normal-impaired DLCO status was associated with an increased risk of respiratory complications (odds ratio, 2.29 [95% CI, 1.12-4.49]; P = .02) and in-hospital complications (odds ratio, 2.83 [95% CI, 1.55-5.26]; P < .001). Type of neoadjuvant therapy was not associated with an increased risk of complications, compared with conventional chemotherapy.

CONCLUSIONS

Reduced postinduction DLCO might predict perioperative outcomes. The use of repeat pulmonary function testing might identify patients at higher risk of morbidity or mortality.

Primary lung cancer in women after previous breast cancer

BACKGROUND

Breast cancer is the most common malignancy among women in the USA. Improved survival has resulted in increasing incidence of second primary malignancies, of which lung cancer is the most common. The United States Preventive Services Task Force (USPSTF) guidelines for lung-cancer screening do not include previous malignancy as a high-risk feature requiring evaluation. The aim of this study was to compare women undergoing resection for lung cancer with and without a history of breast cancer and to assess whether there were differences in stage at diagnosis, survival and eligibility for lung-cancer screening between the two groups.

METHODS

Women who underwent lung-cancer resection between 2000 and 2017 were identified. Demographic, clinicopathological, treatment and outcomes data were compared between patients with a history of breast cancer (BC-Lung) and patients without a history of breast cancer (P-Lung) before lung cancer.

RESULTS

Of 2192 patients included, 331 (15.1 per cent) were in the BC-Lung group. The most common method of lung-cancer diagnosis in the BC-Lung group was breast-cancer surveillance or work-up imaging. Patients in the BC-Lung group had an earlier stage of lung cancer at the time of diagnosis. Five-year overall survival was not statistically significantly different between groups (73.3 per cent for both). Overall, 58.4 per cent of patients (1281 patients) had a history of smoking, and 33.3 per cent (731 patients) met the current criteria for lung-cancer screening.

CONCLUSION

Differences in stage at diagnosis of lung cancer and treatment selection were observed between patients with and without a history of breast cancer. Overall, there were no statistically significant differences in genomic or oncogenic pathway alterations between the two groups, which suggests that lung cancer in patients who previously had breast cancer may not be affected at the genomic level by the previous breast cancer. The most important finding of the study was that a high percentage of women with lung cancer, regardless of breast-cancer history, did not meet the current USPSTF criteria for lung-cancer screening.

Increasing Heart Dose Reduces Overall Survival in Patients Undergoing Postoperative Radiation Therapy for NSCLC

Introduction

Given the concern for cardiopulmonary toxicity in patients with NSCLC undergoing postoperative radiation therapy (PORT), the purpose of this study was to evaluate the association between heart dose and overall survival (OS) in patients undergoing PORT with modern techniques.

Methods

This is a retrospective study of consecutive patients with NSCLC treated with PORT between May 2004 and January 2017. Clinical records were reviewed and radiation dose distributions were analyzed for association with OS.

Results

A total of 284 patients were analyzed. At the time of surgery, most patients had pathologic American Joint Committee on Cancer seventh edition stage III disease (91.2 %) and received either preoperative or adjuvant chemotherapy (92.3 %). Most patients underwent a lobectomy (81.3 %) and had R0 (80.6 %) or R1 (19.4 %) resection. PORT was delivered with a median radiation dose of 54 Gy, and 70.4 % of patients were treated with intensity-modulated radiation therapy. Dosimetric variables across a large range of doses to the heart were highly significant (p < 0.05) for OS. The volume of the heart receiving 8 Gy (HV8) was the most significant dosimetric variable (p < 0.001), and the median HV8 was 35.5 %. The median OS was 33.2 versus 53.6 months (p < 0.005) for patients with HV8 above or below 35.5 %, respectively. On multivariable analysis accounting for other potential prognostic confounders, HV8 remained highly significant (p < 0.001).

Conclusions

The data reveal a strong correlation between increasing heart dose and OS in patients with NSCLC undergoing PORT. Taken together with the recently presented LungART trial, lowering heart dose in PORT patients may help to decrease the risk of morbidity and mortality and improve the therapeutic ratio of PORT.

Treatment of anastomotic recurrence after esophagectomy

BACKGROUND

Isolated local recurrence after curative esophagectomy for esophageal cancer is a rare event. Although it is potentially curable, management can be challenging.

METHODS

We performed a retrospective review of all patients undergoing esophagectomy for esophageal adenocarcinoma (EAC) from 2000 to 2019. Date of recurrence was defined as the date at which the initial abnormal surveillance study or symptomatic presentation led to further workup and subsequent pathologic diagnosis of recurrence. Overall survival after recurrence was estimated using Kaplan-Meier methods and compared between treatment groups using the log-rank test.

RESULTS

Of the 1370 patients with EAC who underwent esophagectomy in our cohort, 531 (39%) developed recurrence of their disease. The 5-year cumulative incidence of recurrence was 2.7% (95% confidence interval [CI], 2.0%-3.6%) for local, 6.3% (95% CI, 5.2%-7.8%) for regional, and 22.0% (95% CI, 20.0%-24.4%) for distant recurrences. On univariable and multivariable competing-risk regression analysis, advanced pT stage, signet ring histology, and serious complication were independently associated with local recurrence. Patients with local recurrence treated with definitive therapy had a median survival after recurrence of 19.1 months (95% CI, 11.4-33.2 months), compared with 10.6 months (95% CI, 8.5-14.2 months) for chemotherapy or radiotherapy alone and 1.73 months (95% CI, 0.23-15.6 months) for no treatment (P<0.001).

CONCLUSIONS

Isolated local recurrence occurred in only 3% of patients. Advanced T stage, signet cell histology, and serious complication were risk factors for recurrence. Although complex surgical resection is required, in very select cases, more-aggressive treatment may be warranted.

Clinical utility of next-generation sequencing-based ctDNA testing for common and novel ALK fusions

OBJECTIVES

Liquid biopsy for plasma circulating tumor DNA (ctDNA) next-generation sequencing (NGS) can detect ALK fusions, though data on clinical utility of this technology in the real world is limited.

MATERIALS AND METHODS

Patients with lung cancer without known oncogenic drivers or who had acquired resistance to therapy (n = 736) underwent prospective plasma ctDNA NGS. A subset of this cohort (n = 497) also had tissue NGS. We evaluated ALK fusion detection, turnaround time (TAT), plasma and tissue concordance, matching to therapy, and treatment response.

RESULTS

ctDNA identified an ALK fusion in 21 patients (3%) with a variety of breakpoints and fusion partners, including EML4, CLTC, and PON1, a novel ALK fusion partner. TAT for ctDNA NGS was shorter than tissue NGS (10 vs. 20 days; p < 0.001). Among ALK fusions identified by ctDNA, 93% (13/14, 95% CI 66%-99%) were concordant with tissue evaluation. Among ALK fusions detected by tissue NGS, 54% (13/24, 95% CI 33%-74%) were concordant with plasma ctDNA. ctDNA matched patients to ALK-directed therapy with subsequent clinical response, including four patients matched on the basis of ctDNA results alone due to inadequate or delayed tissue testing. Serial ctDNA analysis detected MET amplification (n = 2) and ALK G1202R mutation (n = 2) as mechanisms of acquired resistance to ALK-directed therapy.

CONCLUSION

Our findings support a complementary role for ctDNA in detection of ALK fusions and other alterations at diagnosis and therapeutic resistance settings.

Intraoperative opioid exposure, tumour genomic alterations, and survival differences in people with lung adenocarcinoma

BACKGROUND

Opioids have been linked to worse oncologic outcomes in surgical patients. Studies in certain cancer types have identified associations between survival and intra-tumoural opioid receptor gene alterations, but no study has investigated whether the tumour genome interacts with opioid exposure to affect survival. We sought to determine whether intraoperative opioid exposure is associated with recurrence-specific survival and overall survival in early-stage lung adenocarcinoma, and whether selected tumour genomics are associated with this relationship. Associations between ketamine and dexmedetomidine and outcomes were also studied.

METHODS

Surgical patients (N=740) with pathological stage I-III lung adenocarcinoma and next-generation sequencing data were retrospectively reviewed from a prospectively maintained database.

RESULTS

On multivariable analysis, ketamine administration was protective for recurrence-specific survival (hazard ratio = 0.44, 95% confidence interval 0.24-0.80; P=0.007), compared with no adjunct. Higher intraoperative oral morphine milligram equivalents were significantly associated with worse overall survival (hazard ratio=1.09/10 morphine milligram equivalents, 95% confidence interval 1.02-1.17; P=0.010). Significant interaction effects were found between morphine milligram equivalents and fraction genome altered and morphine milligram equivalents and CDKN2A, such that higher fraction genome altered or CDKN2A alterations were associated with worse overall survival at higher morphine milligram equivalents (P=0.044 and P=0.052, respectively). In contrast, alterations in the Wnt (P=0.029) and Hippo (P=0.040) oncogenic pathways were associated with improved recurrence-specific survival at higher morphine milligram equivalents, compared with unaltered pathways.

CONCLUSIONS

Intraoperative opioid exposure is associated with worse overall survival, whereas ketamine exposure is associated with improved recurrence-specific survival in patients with early-stage lung adenocarcinoma. This is the first study to investigate tumour-specific genomic interactions with intraoperative opioid administration to modify survival associations.

Prognostic factors following complete resection of non-superior sulcus lung cancer invading the chest wall

OBJECTIVES

Locally advanced non-small-cell lung cancer (NSCLC) with chest wall invasion carries a high risk of recurrence and portends poor survival (30-40% and 20-50%, respectively). No studies have identified prognostic factors in patients who underwent R0 resection for non-superior sulcus NSCLC.

METHODS

A retrospective review was conducted for all chest wall resections for NSCLC from 2004 to 2018. Patients with superior sulcus tumours, partial (<1 rib) or incomplete (R1/R2) resection or distant metastasis were excluded. Disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Cox proportional hazards modelling was used to determine factors associated with DFS and OS.

RESULTS

A total of 100 patients met inclusion criteria. Seventy-three (73%) patients underwent induction therapy, and all but 12 (16%) patients experienced a partial radiological response. A median of 3 ribs was resected (range 1-7), and 67 (67%) patients underwent chest wall reconstruction. The 5-year DFS and OS were 36% and 45%, respectively. Pathological N2 status [hazard ratio (HR) 3.12, confidence interval (CI) 1.56-6.25; P = 0.001], intraoperative blood transfusion (HR 2.24, CI 1.28-3.92; P = 0.005) and preoperative forced vital capacity (per % forced vital capacity, HR 0.97, CI 0.96-0.99; P = 0.013) were associated with DFS. Increasing pathological stage, lack of radiological response to induction therapy (HR 7.35, CI 2.35-22.99; P = 0.001) and cardiovascular comorbidity (HR 2.43, CI 1.36-4.36; P = 0.003) were associated with OS.

CONCLUSIONS

We demonstrate that blood transfusion and forced vital capacity are associated with DFS after R0 resection for non-superior sulcus NSCLC, while radiological response to induction therapy greatly influences OS. We confirm that pathological nodal status and pathological stage are reproducible determinants of DFS and OS, respectively.

Overall survival with circulating tumor DNA-guided therapy in advanced non-small cell lung cancer

9009

Background: The effectiveness of circulating tumor DNA (ctDNA) at matching patients to life prolonging therapy has been studied mostly in small cohorts with limited follow up. The prognostic value of ctDNA alterations, particularly those absent on tissue, is also unclear. To address these questions, we studied survival outcomes in a prospective cohort of patients (N = 1002) with non-small cell lung cancer (NSCLC). Methods: Adults with metastatic or recurrent NSCLC were eligible if they had no known driver mutation or a known driver with progression following targeted therapy. Patients were enrolled at Memorial Sloan Kettering Cancer Center (New York, NY) starting October 21, 2016; analysis here is from a snapshot November 1, 2020. All patients had ctDNA sequenced via the Resolution ctDx Lung platform. To reduce inclusion of incidental germline mutations, we excluded non-functionally significant mutations with an allele frequency 35-65% that were present in gnomAD. Patients could also receive, at their provider’s discretion, tissue sequencing with MSK-IMPACT, which filters germline and clonal hematopoietic (CH) mutations with matched white blood cell sequencing. We performed survival analyses using Cox proportional hazards models from time of diagnosis of advanced disease to death, left truncating at time of study entry. Results: Of 1002 patients, 348 (35%) were treated with targeted therapy; in 181 of these (52%) the targetable alteration was detected in ctDNA. Patients treated with targeted therapy had prolonged survival whether matched by tissue-based methods (HR 0.39, 95%CI 0.30-0.51) or ctDNA (HR 0.47, 95%CI 0.37-0.61). These benefits persisted across multiple subgroups. ctDNA alterations themselves were associated with worse survival (HR 2.2, 95%CI 1.8-2.8), in a manner that scaled with allele fraction and burden. Of 401 patients with time-matched tissue sampling, 62 (15%) had ctDNA alterations that were absent on IMPACT (“unique” ctDNA alterations). Three such patients had unique ctDNA EGFR T790M mutations leading to changes in therapy. However, unique ctDNA alterations were generally associated with worse survival than no ctDNA alterations (HR 2.5, 95%CI 1.7-3.7) and even tissue-matched ctDNA alterations (HR 1.7, 95%CI 1.1-2.4). Of 98 unique ctDNA mutations, 48 (49%) were detectable in tissue at subthreshold levels, 12 (12%) were filtered by IMPACT as CH or germline, and 38 mutations (39%) were absent even at subthreshold levels. ctDNA alteration burden correlated with radiographic disease extent. In multivariate models with radiographic disease extent and other clinical variables, ctDNA alterations were the strongest independent predictor of worse survival. Conclusions: Our results show that ctDNA may match patients to life-prolonging targeted therapy and have prognostic importance. ctDNA may provide data about a patient’s cancer missed by spatially restricted tissue sequencing. Clinical trial information: NCT01775072.

KRAS G12C Mutation Is Associated with Increased Risk of Recurrence in Surgically Resected Lung Adenocarcinoma

PURPOSE

KRAS ^G12C is the most common KRAS mutation in primary lung adenocarcinoma. Phase I clinical trials have demonstrated encouraging clinical activity of KRAS ^G12C inhibitors in the metastatic setting. We investigated disease-free survival (DFS) and tumor genomic features in patients with surgically resected KRAS ^G12C-mutant lung adenocarcinoma.

EXPERIMENTAL DESIGN

Patients who underwent resection of stage I-III lung adenocarcinoma and next-generation sequencing (NGS) were evaluated. Exclusion criteria were receipt of induction therapy, incomplete resection, and low-quality NGS. Mutations were classified as KRAS wild-type (KRAS ^wt), G12C (KRAS ^G12C), or non-G12C (KRAS ^other). DFS was compared between groups using the log-rank test; factors associated with DFS were assessed using Cox regression. Mutual exclusivity and cooccurrence, tumor clonality, and mutational signatures were assessed.

RESULTS

In total, 604 patients were included: 374 KRAS ^wt (62%), 95 KRAS ^G12C (16%), and 135 KRAS ^other (22%). Three-year DFS was not different between KRAS-mutant and KRAS ^wt tumors. However, 3-year DFS was worse in patients with KRAS ^G12C than KRAS ^other tumors (log-rank P = 0.029). KRAS ^G12C tumors had more lymphovascular invasion (51% vs. 37%; P = 0.032) and higher tumor mutation burden [median (interquartile range), 7.0 (5.3-10.8) vs. 6.1 (3.5-9.7); P = 0.021], compared with KRAS ^other tumors. KRAS ^G12C mutation was independently associated with worse DFS on multivariable analysis. Our DFS findings were externally validated in an independent The Cancer Genome Atlas cohort.

CONCLUSIONS

KRAS ^G12C mutations are associated with worse DFS after complete resection of stage I-III lung adenocarcinoma. These tumors harbor more aggressive clinicopathologic and genomic features than other KRAS-mutant tumors. We identified a high-risk group for whom KRAS ^G12C inhibitors may be investigated to improve survival.

The American College of Surgeons Surgical Risk Calculator performs well for pulmonary resection: A validation study

OBJECTIVE

The American College of Surgeons National Surgical Quality Improvement Program Surgical Risk Calculator (NSQIP SRC) was developed to estimate the risk of postoperative morbidity and mortality within 30 days of an operation. We sought to externally evaluate the performance of the NSQIP SRC for patients undergoing pulmonary resection.

METHODS

Patients undergoing pulmonary resection at our center between January 2016 and December 2018 were included. Using data from our institution's prospectively maintained Society of Thoracic Surgeons General Thoracic Database, we identified 2514 patients. We entered requisite patient demographic information, preoperative risk factors, and procedural details into the online calculator. Predicted performance of the calculator versus observed outcomes was assessed by discrimination (concordance index [C-index]) and calibration.

RESULTS

The observed and predicted probabilities of any complication were 8.3% and 9.9%, respectively, and of serious complications were 7.4% and 9.2%, respectively. Observed and predicted 30-day mortality were 0.5% and 0.9%, respectively. The C-index for readmission was 0.644; the C-indices corresponding to all other outcomes in the NSQIP SRC ranged from 0.703 to 0.821. Calibration curves indicated excellent calibration for all binary end points, with the exception of renal failure (predicted underestimated observed probabilities), discharge to a nursing or rehabilitation facility (overestimated), and sepsis (overestimated). Correlation between predicted and observed length of stay was moderate (Spearman coefficient, 0.562), and calibration was good.

CONCLUSIONS

Except for readmission, renal failure, discharge to a location other than home, and sepsis, the NSQIP SRC can be used to reasonably predict postoperative complications in patients undergoing pulmonary resection.

Is Routine Chest Radiography Necessary After Endobronchial Ultrasound-guided Fine Needle Aspiration?

BACKGROUND

Chest radiography is routinely performed after endobronchial ultrasound-guided fine needle aspiration (EBUS-FNA) to detect clinically occult pneumothorax. Because the established rate of postprocedure pneumothorax is low, this study sought to determine whether routine chest radiography can be safely eliminated and to ascertain the potential cost reduction with its omission.

METHODS

Patients who underwent EBUS-FNA between January 1, 2017 and December 31, 2018 at Memorial Sloan Kettering Cancer Center (New York, NY) were retrospectively identified. Patient-related factors were summarized using descriptive statistics. Outcomes were compared using the χ², Fisher exact, and analysis of variance tests. Univariate regression analysis was used to identify factors predictive of postprocedure pneumothorax.

RESULTS

A total of 757 patients were included in the study: 72.4% (548 of 757) underwent routine chest radiography in the postanesthesia care unit. Clinically relevant or radiographically evident pneumothorax developed in 1.5% of patients (11 of 757). Of the patients who underwent chest radiography, 0.5% (3 of 548) required unplanned admission for postprocedure pneumothorax, and 0.2% (1 of 548) required tube thoracostomy. Of the 209 patients who did not undergo chest radiography, none experienced a clinically evident pneumothorax. In total, only 1 patient (0.1%) had symptomatic pneumothorax. The pneumothorax event rate was so low that no association with demographic or clinical factors and no predictive factors could be identified. The number of patients needed to be screened by chest radiography to identify 1 patient requiring deviation from routine management is 183. The potential total cost reduction if routine chest radiography had been eliminated was $33,950.

CONCLUSIONS

The extremely low rate of postprocedure pneumothorax precluded informative statistical analysis. Routine chest radiography after EBUS-FNA may not be necessary, and its omission may confer a cost savings.

External Validation of Surgical Risk Preoperative Assessment System in Pulmonary Resection

BACKGROUND

Accurate preoperative risk assessment is necessary for informed decision making for patients and surgeons. Several preoperative risk calculators are available but few have been examined in the general thoracic surgical patient population. The Surgical Risk Preoperative Assessment System (SURPAS), a risk-assessment tool applicable to a wide spectrum of surgical procedures, was developed to predict the risks of common adverse postoperative outcomes using a parsimonious set of preoperative input variables. We sought to externally validate the performance of SURPAS for postoperative complications in patients undergoing pulmonary resection.

METHODS

Between January 2016 and December 2018, 2514 patients underwent pulmonary resection at our center. Using data from our institution's prospectively maintained database, we calculated the predicted risks of 12 categories of postoperative outcomes using the latest version of SURPAS. Performance of SURPAS against observed patient outcomes was assessed by discrimination (concordance index) and calibration (calibration curves).

RESULTS

The discrimination ability of SURPAS was moderate across all outcomes (concordance indices, 0.640 to 0.788). Calibration curves indicated good calibration for all outcomes except infectious and cardiac complications, discharge to a location other than home, and mortality (all overestimated by SURPAS).

CONCLUSIONS

SURPAS demonstrates outcomes for pulmonary resections with reasonable predictive ability. Discretion should be applied when assessing risk for postoperative infectious and cardiac complications, discharge to a location other than home, and mortality. Although the parsimonious nature of SURPAS is one of its strengths, its performance might be improved by including additional factors known to influence outcomes after pulmonary resection, such as sex and pulmonary function.

Performance Comparison Between SURPAS and ACS NSQIP Surgical Risk Calculator in Pulmonary Resection

BACKGROUND

Accurate preoperative risk assessment is critical for informed decision making. The Surgical Risk Preoperative Assessment System (SURPAS) and the National Surgical Quality Improvement Program (NSQIP) Surgical Risk Calculator (SRC) predict risks of common postoperative complications. This study compares observed and predicted outcomes after pulmonary resection between SURPAS and NSQIP SRC.

METHODS

Between January 2016 and December 2018, 2514 patients underwent pulmonary resection and were included. We entered the requisite patient demographics, preoperative risk factors, and procedural details into the online NSQIP SRC and SURPAS formulas. Performance of the prediction models was assessed by discrimination and calibration.

RESULTS

No statistically significant differences were found between the 2 models in discrimination performance for 30-day mortality, urinary tract infection, readmission, and discharge to a nursing or rehabilitation facility. The ability to discriminate between a patient who will develop a complication and a patient who will not was statistically indistinguishable between NSQIP and SURPAS, except for renal failure. With a C index closer to 1.0, the NSQIP performed significantly better than the SURPAS SRC in discriminating risk of renal failure (C index, 0.798 vs 0.694; P = .003). The calibration curves of predicted and observed risk for each model demonstrate similar performance with a tendency toward overestimation of risk, apart from renal failure.

CONCLUSIONS

Overall, SURPAS and NSQIP SRC performed similarly in predicting outcomes for pulmonary resections in this large, single-center validation study with moderate to good discrimination of outcomes. Notably, SURPAS uses a smaller set of input variables to generate the preoperative risk assessment. The addition of thoracic-specific input variables may improve performance.

Pericardial Effusions in Patients With Cancer: Anesthetic Management and Survival Outcomes

OBJECTIVES

The objective of this study was to describe practice patterns of anesthetic management during pericardial window creation.

DESIGN

Retrospective observational cohort study.

SETTING

Single tertiary cancer center.

PARTICIPANTS

A total of 150 patients treated for cancer between 2011 and 2015 were included in the study.

MEASUREMENTS AND MAIN RESULTS

The primary objective was to evaluate anesthetic management in pericardial window creation. Secondary outcomes were 30-day mortality and overall survival after pericardial window creation. Thirty-day mortality was 19.3%, and median survival was 5.84 months. Higher American Society of Anesthesiologists (ASA) physical status of patients was associated with preinduction arterial line placement (51% ASA 3 v 79% ASA 4; p = 0.002) and use of etomidate for anesthetic induction (34% ASA 3 v 60% ASA 4; p = 0.003). However, there was no association between anesthetic management and presence of tamponade in these patients. Cardiac aspirate volume (per 10 mL: odds ratio [OR], 1.02 [95% CI, 1.0-1.04]; p = 0.026) and intraoperative arrhythmia (atrial fibrillation: OR, 6.76 [95% CI, 1.2-37.49]; p = 0.029; sinus tachycardia: OR, 4.59 [95% CI, 1.25-16.90]; p = 0.022) were associated independently with increased 30-day mortality. High initial heart rate (per 10 beats per minute: hazard ratio [HR], 1.18 [95% CI, 1.05-1.33]; p = 0.005) in the operating room and intraoperative sinus tachycardia (HR, 1.86 [95% CI, 1.15-3.03]; p = 0.012) were associated independently with worse overall survival.

CONCLUSION

Risk of death after pericardial window creation remains high in patients with cancer. Variations in anesthetic management did not affect survival in oncologic patients with pericardial effusions.

How Effective Is Neoadjuvant Therapy Followed by Surgery for Pathologic Single-Station N2 Non-Small Cell Lung Cancer?

The optimal treatment strategy for pathologic single-station N2 (pN2a1) non-small cell lung cancer (NSCLC)-surgery first followed by adjuvant treatment (SF) or neoadjuvant therapy followed by surgery (NS)-remains unclear. We compared disease-free survival (DFS) and overall survival (OS) after NS versus SF for pN2a1 NSCLC. We retrospectively identified patients with pN2a1 NSCLC resected between 2000 and 2018. Patients in the SF group had cN0 disease and were treated with surgery before adjuvant chemotherapy; patients in the NS group had known preoperative nodal disease, cN2 disease, and were treated with neoadjuvant therapy before surgery. The matching-weights procedure was applied to generate a cohort with similar characteristics between groups. DFS and OS were calculated using the Kaplan-Meier approach and compared between groups using weighted log-rank test and Cox proportional hazards models. We identified 227 patients with pN2a1 disease: 121 treated with SF and 106 with NS. After the matching-weights procedure, 5- and 10-year DFS were 45% and 27% for SF versus 26% and 21% for NS (log-rank P = 0.056; hazard ratio [HR], 1.61; 95% confidence interval [CI], 0.98-2.65); 5- and 10-year OS were 49% and 30% for SF versus 43% and 20% for NS (log-rank P = 0.428; HR, 1.24; 95% CI, 0.67-2.28). SF and NS for pN2a1 NSCLC resulted in similar survival. A study comparing SF for known preresectional pN2a1 with occult pN2a1 disease could be a next step. Further investigation of SF for known N2a1 versus occult pN2a1 disease could power a clinical trial focused on N2a NSCLC.

Abstract 709: The utility of plasma ctDNA for detection of KRAS G12C and other mutations in lung cancers

Background: KRAS is the most common oncogene in lung cancer, but has historically been considered undruggable. The recent development of mutant-selective KRAS G12C inhibitors has for the first time created potential therapeutic opportunities for this unmet need. Simultaneously, circulating tumor DNA (ctDNA) is increasingly being used to detect targetable oncogenes in patients with metastatic lung cancers. There is limited data regarding the utility of plasma ctDNA in specifically identifying KRAS G12C mutations.

Methods: Plasma was collected from 599 patients with lung cancer seen at Memorial Sloan Kettering Cancer Center between 10/2016 and 1/2019. ctDNA sequencing was performed using the ctDX-Lung Assay (Resolution Bioscience; Kirkland, WA). Tissue DNA sequencing was carried out using the MSK-IMPACT assay.

Results: Mutations in KRAS (KRAS+) were detected in 129 patients (21.5%). Of patients with KRAS+ lung cancers, 116 had metastatic disease at the time of plasma testing. Plasma testing was carried out within 90 days of metastatic diagnosis in 92 of the 116 metastatic KRAS+ patients (79.3%), of whom 66 patients had both plasma and tissue sequencing available for comparison. 59 of the 66 patients (89.4%) had not had systemic treatment at the time of plasma testing. Average turn-around-time (TAT) for ctDNA testing in this cohort of 66 patients was 10 days, while average TAT for tissue sequencing was 22 days. ctDNA detected a KRAS mutation in 48 of the 66 patients (72.7%). A G12C mutation was found in the tissue and/or blood from 29 patients (43.9%), while 37 patients (56.1%) had other KRAS mutations. In one patient with a G12C mutation detected on plasma testing, no KRAS mutation or other known oncogenic drivers were found on tissue testing, though with limited tumor cells in the tissue sample. 75.6% of the patients with G12C mutations had KRAS detectable in the plasma, as compared to 70.3% of patients with other KRAS mutations (p=0.6). Within the cohort of patients with paired tissue and plasma testing, at a median follow-up of 202 days post-metastatic diagnosis, survival was longer in those patients without detectable KRAS in the plasma as compared to those patients with detectable plasma KRAS (log rank (Mantel-Cox), p&lt;0.001, log rank HR 7.9, 95% CI: 3.7-16.8).

Conclusion: Plasma testing was able to rapidly detect KRAS G12C mutations in the majority of patients with this alteration, which may guide G12C inhibitor therapy. In our cohort, patients that shed KRAS mutant DNA into the plasma had shorter survival.

Citation Format: Yonina R. Murciano-Goroff, Kathryn C. Arbour, Michael D. Offin, Hai-Yan Y. Tu, Emily S. Lebow, Tristan S. Shaffer, Caterina Bertucci, Syed A. Hosseini, Kavita Garg, Lee P. Lim, Mark Li, Jason C. Chang, Jorge S. Reis-Filho, Pedram Razavi, James M. Isbell, Gregory J. Riely, David M. Hyman, Piro Lito, Bob T. Li. The utility of plasma ctDNA for detection of KRAS G12C and other mutations in lung cancers [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 709.

The Underlying Tumor Genomics of Predominant Histologic Subtypes in Lung Adenocarcinoma

INTRODUCTION

The purpose of the study is to genomically characterize the biology and related therapeutic opportunities of prognostically important predominant histologic subtypes in lung adenocarcinoma (LUAD).

METHODS

We identified 604 patients with stage I to III LUAD who underwent complete resection and targeted next-generation sequencing using the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets platform. Tumors were classified according to predominant histologic subtype and grouped by architectural grade (lepidic [LEP], acinar or papillary [ACI/PAP], and micropapillary or solid [MIP/SOL]). Associations among clinicopathologic factors, genomic features, mutational signatures, and recurrence were evaluated within subtypes and, when appropriate, quantified using competing-risks regression, with adjustment for pathologic stage and extent of resection.

RESULTS

MIP/SOL tumors had higher tumor mutational burden (p < 0.001), fraction of genome altered (p = 0.001), copy number amplifications (p = 0.021), rate of whole-genome doubling (p = 0.008), and number of oncogenic pathways altered ( p < 0.001) as compared with LEP and ACI/PAP tumors. Across all tumors, mutational signatures attributed to APOBEC activity were associated with the highest risk of postresection recurrence: SBS2 (p = 0.021) and SBS13 (p = 0.005). Three oncogenic pathways (p53, Wnt, Myc) were altered with statistical significance in MIP/SOL tumors. Compared with LEP and ACI/PAP tumors, MIP/SOL tumors had a higher frequency of targetable BRAF-V600E mutations (p = 0.046). Among ACI/PAP tumors, alterations in the cell cycle (p < 0.001) and PI3K (p = 0.002) pathways were associated with recurrence; among MIP/SOL tumors, only PI3K alterations were associated with recurrence (p = 0.049).

CONCLUSIONS

These results provide the first in-depth assessment of tumor genomic profiling of predominant LUAD histologic subtypes, their associations with recurrence, and their correlation with targetable driver alterations in patients with surgically resected LUAD.

Early ctDNA response assessment for prediction of platinum sensitivity in small cell lung cancer

9067

Background: Small cell lung cancer (SCLC) is an aggressive disease, characterized by inevitable chemotherapy resistance and rapid progression. We hypothesized that circulating tumor DNA (ctDNA) analysis can rapidly identify sensitivity to platinum-based therapy. Methods: Patients with SCLC at Memorial Sloan Kettering Cancer Center underwent serial plasma collections, including prior to the start of treatment and prior to Cycle 2 Day 1 of therapy (C2D1). Tumor mutations were identified from pre-treatment biopsies by MSK-IMPACT and/or pre-treatment plasma by CAncer Personalized Profiling by deep Sequencing (CAPP-Seq). Median variant allele fraction (VAF) of all mutations was monitored on subsequent blood draws using CAPP-Seq. Progression free survival (PFS) was measured from the time of first pre-treatment blood draw. Results: Plasma was collected from 19 patients treated with carboplatin and etoposide, including three who received concurrent atezolizumab. Seven were female, and mean age was 64.5 years. ctDNA was detected in 17 patients (89%), including in the two patients in our series with limited stage disease. The most common mutations were in TP53 and RB1 in 14 and 6 patients, respectively. Fourteen patients had available plasma at C2D1. At baseline prior to treatment, median VAF did not differ significantly between radiologic responders and non-responders (9.4% versus 30.3%, p = 0.35). After one cycle of chemotherapy, the VAF percent decrease was significantly more in responders versus non-responders (-96.9% versus -10.3%, p < 0.001). Median VAF was therefore significantly lower by C2D1 in patients who responded compared to non-responders (0.51% versus 27.2%, p = 0.02). Those who ultimately responded to therapy all had a > 2 fold decrease in VAF by C2D1. With a median follow-up of 180 days, PFS was significantly longer in patients with > 2 fold decrease in VAF by C2D1 (6.4 versus 1.9 months, log rank p < 0.001). Conclusions: A 2-fold decrease in plasma VAF by C2D1 predicted platinum-sensitivity in SCLC and was associated with longer PFS. ctDNA may permit early assessment of benefit and expedite alternative treatment options for those without significant decrease in median VAF after one cycle of therapy.

PET-directed chemoradiation (CRT) with induction FOLFOX compared to induction carboplatin/paclitaxel (CP) in patients with locally advanced esophageal adenocarcinoma (EA)

4554

Background: Induction chemotherapy with PET-directed CRT and surgery is the standard treatment for locally advanced EA at our institution. Following results of the CALGB 80803 trial, FOLFOX has recently replaced CP as the preferred induction regimen. Methods: We retrospectively evaluated patients with locally advanced EA treated with induction CP vs FOLFOX, followed by trimodality therapy between January 2010 and June 2019. Patients treated with CP with RT followed by surgery without induction chemo were also included. We compared pathological complete response (pCR) and near pCR (ypN0 with ≥90% response) rates in the induction FOLFOX group to the induction CP and no-induction groups. Univariable and multivariable analyses were used to adjust for confounding factors. Disease-free survival (DFS) was estimated by the Kaplan-Meier method and compared between groups using max-combo weighted log rank test. Results: 445 patients were included. Patients in the induction FOLFOX group had significantly higher pCR and near pCR rates vs induction CP patients. Notably, pCR rate was 38% among FOLFOX PET responders vs 19% in non-responders. In multivariable analysis, compared to induction CP, induction FOLFOX administration was an independent predictor of near pCR (OR: 2.22, 95%CI: 1.20-4.20, p = 0.012). Compared to 24% pCR rate among no-induction patients, induction FOLFOX pCR rate was slightly higher at 32%. DFS by 2-years was higher in induction FOLFOX compared to no-induction-treated patients (62% vs. 42%, p = 0.05). Postoperative complication rates were similar among the three groups. Conclusions: PET-directed CRT with FOLFOX instead of CP improves pCR and near pCR rates. Improved DFS was observed in the FOLFOX vs no-induction patients. Longer follow-up is needed to confirm any survival benefits. [Table: see text]

MSK-ACCESS for noninvasive somatic mutation profiling of lung cancers utilizing circulating tumor DNA

3529

Background: Circulating cell-free DNA (cfDNA) next-generation sequencing (NGS) is a promising strategy for non-invasive molecular profiling of cancers. MSK-ACCESS (Analysis of Circulating cfDNA to Evaluate Somatic Status) is a hybridization-capture targeted NGS assay that detects somatic variants in select exons of 129 genes with matched white blood cell sequencing. We present the initial clinical experience with MSK-ACCESS among patients with advanced non-small cell lung cancer (NSCLC). Methods: Patients with stage IV NSCLC underwent prospective MSK-ACCESS testing at initial diagnosis or progression of disease on targeted therapy between June 2019 and January 2020. A subset of patients had matched tissue-based NGS testing with the MSK-IMPACT 468 gene assay. We assessed oncogenic driver detection, turnaround time, plasma-tissue concordance, and matching to therapy. National Comprehensive-Cancer Network designated driver alterations were included in evaluation of tissue-plasma concordance (EGFR, ALK, KRAS, MET, RET, BRAF, HER2, ROS1, NTRK). Turnaround time was compared by a two-sided Wilcoxon signed-rank test. Results: A total of 201 patients with NSCLC had MSK-ACCESS testing at initial diagnosis (n = 79) or following progression of disease (n = 122). The median turn-around-time from plasma collection to MSK-ACCESS report was 16 days (range: 9 – 36 days) compared to 19 days from lab receipt of tissue to report (range: 12 – 57) for MSK-IMPACT (p < 0.001). Among patients with a driver detected on MSK-ACCESS, 100% (92/92) had an identical driver detected on MSK-IMPACT. Among patients with a driver detected on MSK-IMPACT, 75% (92/123) had an identical driver detected on MSK-ACCESS. This rate was similar among patients who were treatment-naive (74%; 64/86) and had disease progression (76%, 28/37) at the time of MSK-ACCESS. MSK-ACCESS identified driver alterations that directly guided first-line targeted therapy (n = 18) with response in all patients with available radiographic follow-up (n = 10), including a patient without confirmatory tissue testing. MSK-ACCESS identified resistance alterations among patients with disease progression including EGFR T790M, EGFR C797S, ROS1 G2032R, as well as a BRAF fusion. Conclusions: MSK-ACCESS successfully identified driver alterations with high concordance to tissue-based testing, directly guided patients to therapy with clinical responses, and detected known and novel resistance mechanisms. This assay warrants further clinical development to guide and facilitate precision oncology.