Preoperative 18F-FDG PET/CT and CT radiomics for identifying aggressive histopathological subtypes in early stage lung adenocarcinoma.

Lung adenocarcinoma (ADC) is the most common non-small cell lung cancer. Surgical resection is the primary treatment for early-stage lung ADC while lung-sparing surgery is an alternative for non-aggressive cases. Identifying histopathologic subtypes before surgery helps determine the optimal surgical approach. Predominantly solid or micropapillary (MIP) subtypes are aggressive and associated with a higher likelihood of recurrence and metastasis and lower survival rates. This study aims to non-invasively identify these aggressive subtypes using preoperative 18F-FDG PET/CT and diagnostic CT radiomics analysis. We retrospectively studied 119 patients with stage I lung ADC and tumors ≤ 2 cm, where 23 had aggressive subtypes (18 solid and 5 MIPs). Out of 214 radiomic features from the PET/CT and CT scans and 14 clinical parameters, 78 significant features (3 CT and 75 PET features) were identified through univariate analysis and hierarchical clustering with minimized feature collinearity. A combination of Support Vector Machine classifier and Least Absolute Shrinkage and Selection Operator built predictive models. Ten iterations of 10-fold cross-validation (10 ×10-fold CV) evaluated the model. A pair of texture feature (PET GLCM Correlation) and shape feature (CT Sphericity) emerged as the best predictor. The radiomics model significantly outperformed the conventional predictor SUVmax (accuracy: 83.5% vs. 74.7%, p = 9e-9) and identified aggressive subtypes by evaluating FDG uptake in the tumor and tumor shape. It also demonstrated a high negative predictive value of 95.6% compared to SUVmax (88.2%, p = 2e-10). The proposed radiomics approach could reduce unnecessary extensive surgeries for non-aggressive subtype patients, improving surgical decision-making for early-stage lung ADC patients.

Organ-specific heterogeneity in tumor-infiltrating immune cells and cancer antigen expression in primary and autologous metastatic lung adenocarcinoma.

BACKGROUND: Tumor immune microenvironment (TIME) and cancer antigen expression, key factors for the development of immunotherapies, are usually based on the data from primary tumors due to availability of tissue for analysis; data from metastatic sites and their concordance with primary tumor are lacking. Although of the same origin from primary tumor, organ-specific differences in the TIME in metastases may contribute to discordant responses to immune checkpoint inhibitor agents. In immunologically 'cold' tumors, cancer antigen-targeted chimeric antigen receptor (CAR) T-cell therapy can promote tumor-infiltrating lymphocytes; however, data on distribution and intensity of cancer antigen expression in primary tumor and matched metastases are unavailable. METHODS: We performed a retrospective review of a prospectively maintained database of patients who had undergone curative resection of pathological stage I-III primary lung adenocarcinoma from January 1995 to December 2012 followed by metastatic recurrence and resection of metastatic tumor (n=87). We investigated the relationship between the primary tumor and metastasis TIME (ie, tumor-infiltrating lymphocytes, tumor-associated macrophages, and programmed death-ligand 1 (PD-L1)) and cancer antigen expression (ie, mesothelin, CA125, and CEACAM6) using multiplex immunofluorescence. RESULTS: Brain metastases (n=36) were observed to have fewer tumor-infiltrating lymphocytes and greater PD-L1-negative tumor-associated macrophages compared with the primary tumor (p<0.0001); this relatively inhibitory TIME was not observed in other metastatic sites. In one in three patients, expression of PD-L1 is discordant between primary and metastases. Effector-to-suppressor (E:S) cell ratio, median effector cells (CD20+ and CD3+) to suppressor cells (CD68/CD163+) ratio, in metastases was not significantly different between patients with varying E:S ratios in primary tumors. Cancer antigen distribution was comparable between primary and metastases; among patients with mesothelin, cancer antigen 125, or carcinoembryonic antigen adhesion molecule 6 expression in the primary tumor, the majority (51%-75%) had antigen expression in the metastases; however, antigen-expression intensity was heterogenous. CONCLUSIONS: In patients with lung adenocarcinoma, brain metastases, but not other sites of metastases, exhibited a relatively immune-suppressive TIME; this should be considered in the context of differential response to immunotherapy in brain metastases. Among patients with cancer antigen expression in the primary tumor, the majority had antigen expression in metastases; these data can inform the selection of antigen-targeted CARs to treat patients with metastatic lung adenocarcinoma.

Tertiary Lymphoid Structures as Mediators of Immunotherapy Response.

Since its first application in the treatment of cancer during the 1800s, immunotherapy has more recently become the leading edge of novel treatment strategies. Even though the efficacy of these agents can at times be predicted by more traditional metrics and biomarkers, often patient responses are variable. TLS are distinct immunologic structures that have been identified on pathologic review of various malignancies and are emerging as important determinants of patient outcome. Their presence, location, composition, and maturity are critically important in a host's response to malignancy. Because of their unique immunogenic niche, they are also prime candidates, not only to predict and measure the efficacy of immunotherapy agents, but also to be potentially inducible gatekeepers to increase therapeutic efficacy. Herein, we review the mechanistic underpinnings of TLS formation, the data on its relationship to various malignancies, and the emerging evidence for the role of TLS in immunotherapy function.

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.

Tumor Spread Through Air Spaces Is a Predictor of Occult Lymph Node Metastasis in Clinical Stage IA Lung Adenocarcinoma.

INTRODUCTION: In patients with stage IA lung adenocarcinoma (ADC), sublobar resection and tumor spread through air spaces (STAS) are associated with high rates of locoregional recurrence, half of which occur within the regional lymph nodes (LNs). Our objectives were to investigate the association between occult LN metastasis (ONM) and STAS and to assess their prognostic value in patients with clinical stage IA lung ADC. METHODS: The association between STAS and ONM was analyzed in patients who underwent lobectomy and LN dissection for clinical stage IA lung ADC (n = 809). Multivariable logistic regression analysis was carried out to identify predictors of ONM. Site-specific recurrence by surgical procedure was investigated in patients with pathologic node-negative disease (n = 1055) using a competing risk approach. RESULTS: ONM was identified in 129 patients (16%)-one-third of ONMs were located only in intrapulmonary nodes. STAS was more common in patients with ONM than in those without ONM (67% versus 39%; p < 0.001) and in patients with multiple ONMs than in those with a single ONM (86%-89% versus 60%-67%). STAS was a significant predictor of ONM (p = 0.004) on multivariable analysis, independent of tumor size, maximum standardized uptake value, and lymphovascular invasion. In patients with STAS-positive ADC (high ONM risk), the risk of recurrence in the treated lobe and regional LNs increased as the extent of resection decreased (recurrence risk: lobectomy < segmentectomy < wedge resection). In patients with STAS-negative ADC, the risk of locoregional recurrence did not differ by procedure type. CONCLUSIONS: Presence of STAS predicts ONM in patients with clinical stage IA lung ADC and can help stratify risk of recurrence by extent and type of resection.

Decreasing use of epidural analgesia with increasing minimally invasive lobectomy: Impact on postoperative morbidity.

OBJECTIVE: The goal of this study is to investigate the use of EA and its impact on the postoperative short-term outcomes of patients with non-small cell lung cancer (NSCLC) who received a lobectomy by either minimally invasive surgery (MIS) or thoracotomy. MATERIALS AND METHODS: We investigated 793 patients who underwent lobectomy for pathological stage I-III NSCLC without induction therapy during two time periods, an early-time period (2009-2010: MIS, n = 204 [53%]; and thoracotomy, n = 182 [47%]) and a late-period (2014-2015: MIS, n = 308 [76%]; and thoracotomy, n = 99 [24%]). Patient characteristics, including pulmonary function tests, comorbidities, and use of EA, as well as short-term outcomes, including length of stay, morbidity, and mortality were assessed and compared between early-and late-time periods. We also compared patients who received EA (n = 150) with patients who did not receive EA (n = 158) following MIS lobectomy in the late-time period. RESULTS: The use of MIS lobectomy increased during the late-time period compared to the early-time period (p < 0.001). In patients who underwent MIS lobectomy, the use of EA significantly decreased in the late-time period compared to the early-time period (2009-2010 vs. 2014-2015, 95% vs. 51%; p < 0.001). There was no difference in postoperative morbidity and mortality between the two time periods in both MIS and thoracotomy. In the late-time period MIS group, the length of stay in the no EA group (n = 150) was shorter than that in the EA group (n = 158) (3 vs. 4 days, p = 0.038). There was no difference in morbidity and mortality between the EA and no EA groups. CONCLUSION: In our study cohort, the observed decrease in the use of EA with the increasing rate of MIS lobectomy did not negatively affect postoperative short-term outcomes.

Histologic subtyping in pathologic stage I-IIA lung adenocarcinoma provides risk-based stratification for surveillance.

BACKGROUND: We hypothesize that recurrence hazard following resection for stage I-IIA lung adenocarcinoma (ADC) varies according to histologic subtype, which may provide risk stratification for surveillance better than the current uniform follow-up protocol. RESULTS: Presence (≥5%) of high-grade histologic subtypes (MIP and/or SOL) was associated with a significantly higher recurrence hazard: (1) presence of either MIP or SOL was associated with a significant increase in recurrence hazard during the first two years after surgery; (2) presence of SOL was associated with an increase in recurrence hazard-in particular, distant recurrence hazard-during the first year after surgery; (3) absence of high-grade subtypes (515/1,572 patients) was associated with a very low recurrence hazard (<2% risk/year) during the first ten years after surgery. METHODS: All hematoxylin and eosin-stained tumor slides from pathologic stage I-IIA lung ADC (n = 1572) were reviewed for quantification of the percentage of each histological subtype. Recurrence hazard was estimated using the Kernel-Epanechnikov smoothing procedure. The association between recurrence hazard and high-grade histologic subtypes (micropapillary [MIP] and solid [SOL]) was assessed. CONCLUSIONS: Our findings suggest that histologic subtyping has utility for identifying recurrence hazard for surgically resected stage I-IIA lung ADC patients and provide rationale for establishing risk-based surveillance.

Surgical management of esophageal cancer.

Esophageal cancer (EC) is an aggressive malignancy associated with an overall poor prognosis. The specific risk factors for EC vary by histologic type as well as geographic distribution but there is no widely applicable screening strategy to date. Patients can present with vague symptoms which can prove to be a diagnostic challenge. Furthermore, cases tend to present at a late stage, making therapeutic approach difficult. Despite ongoing changes in management strategy, surgery remains the only viable option for cure in early stage malignancy. Advances in operative and peri-operative management have led to a relatively safe and efficacious procedure that provides durable therapy. Additionally, careful consideration of procedure specific factors can help maximize patient benefit. This review focuses on the surgical approaches to the management of EC and highlights select current trends and recent advances.

Chemotherapy-induced immunomodulation in non-small-cell lung cancer: a rationale for combination chemoimmunotherapy.

Spurred by the survival benefits seen with the use of checkpoint blockade in non-small-cell lung cancer (NSCLC), there has been a growing interest in the potential applications of immunotherapy. Despite this, the objective response rate for single-agent immunotherapy remains ≤20% in patients with advanced NSCLC. A combinatorial approach that utilizes both chemotherapy and immunotherapy is a potential strategy to increase antitumor efficacy. Accumulating evidence has shown that the immunomodulatory effects of chemotherapeutic agents can be exploited in a combinational approach. Herein, we review the influence of specific chemotherapeutic agents on the tumor immune microenvironment in preclinical and clinical studies, and establish the rationale for combination chemoimmunotherapy for the treatment of NSCLC.

American College of Surgeons National Surgical Quality Improvement Program as a quality-measurement tool for advanced cancer patients.

BACKGROUND: Multiple studies have shown the significantly increased post-operative morbidity and mortality of patients undergoing palliative operations. It has been proposed by some authors that the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database can be used reliably to develop risk-calculators or as an aid for clinical decision-making in advanced cancer patients. ACS-NSQIP is a population-based database that by design only captures outcomes data for the first 30-day following an operation. We considered the suitability of these data as a tool for decision-making in the advanced cancer patient. METHODS: Six-year retrospective review of a single institution's ACS-NSQIP database for cases identified as "Disseminated Cancer". Procedures performed with palliative intent were identified and analyzed. RESULTS: Of 7,763 patients within the ACS-NSQIP database, 138 (1.8%) were identified as having "Disseminated Cancer". Of the remaining 7,625 entries only 4,486 contained complete survival data for analysis. Thirty-day mortality within the "Disseminated Cancer" group was higher when compared to all other surgical patients (7.9% vs. 0.9%, P<0.001). Explicit chart review of these 138 patients revealed that 32 (23.2%) had undergone operations with palliative intent. Overall survival for palliative and non-palliative operations was significantly different (104 vs. 709 days, P<0.001). When comparing palliative to non-palliative procedures using ACS-NSQIP data, we were unable to detect a difference in 30-day mortality (9.4% vs. 7.5%, P=0.72). CONCLUSIONS: Calculations utilizing ACS-NSQIP data fail to demonstrate the increased mortality associated with palliative operations. Patients diagnosed with advanced cancer are not adequately represented within the database due to the limited number of cases collected. Also, more suitable outcomes measures for palliative operations such as pain relief, functional status, and quality of life, are not captured. Therefore, the sole use of thirty-day morbidity and mortality data contained in the ACS-NSQIP database is insufficient to make sound decisions for surgical palliation.