Could tumor spread through air spaces benefit from adjuvant chemotherapy in stage I lung adenocarcinoma? A multi-institutional study

Survival and pulmonary function in stage IA non-small cell lung cancer after sublobar resection versus lobectomy: An updated meta-analysis

Traditionally, lobectomy was standard for stage IA non-small-cell lung cancer (NSCLC). Recent RCTs suggest sublobar resection's comparable outcomes. Our meta-analysis, incorporating 30 studies (including four RCTs), assessed sublobar resection's efficacy. Employing a random-effects model and I2 statistics for heterogeneity, we found sublobar resection reduced DFS (HR 1.31, p < 0.01) and OS (HR 1.27, p < 0.01) overall. However, RCT subgroup analysis showed no significant differences in DFS (p = 0.28) or OS (p = 0.62). Sublobar resection is a viable option for well-selected patients.

[Selection of postoperative adjuvant therapy for patients with stage IB lung adenocarcinoma: analysis of 653 cases]

OBJECTIVE

To explore the optimal postoperative adjuvant regimens for patients with stage IB lung adenocarcinoma.

METHODS

We respectively analyzed the data of 653 patients undergoing surgery for stage IB lung adenocarcinoma in our hospital from January, 2013 to December, 2021. The 5-year disease-free survival (DFS) and overall survival (OS) rates were compared among the patients receiving postoperative adjuvant therapy with epidermal growth factor-tyrosine kinase inhibitors (EGFR-TKIs group, n=111), chemotherapy (CT group, n=108) and clinical observation (CO group, n=434).

RESULTS

In TKIs, CT, and CO groups, the 5-year DFS rates were 92.8%, 80.7%, and 81.7%, respectively, significantly higher in TKIs group than in CO group (P < 0.01). The 3-year OS rates of the 3 groups were 96.8%, 97.1%, and 91.7%, respectively. Subgroup analysis showed that in TKIs, CT, and CO groups, the 5-year DFS rates of patients with with T3-4 cmN0M0 were 92.6%, 84.0%, and 81.4%, respectively, significantly higher in TKIs group than in CO group (P < 0.05); the 5-year DFS rates of T2ViscPlN0M0 patients were 95.1%, 71.4%, and 83.5%, respectively. Multivariate COX regression analysis showed that age (P < 0.05; HR=0.631, 95% CI: 0.401-0.993), solid nodules (P < 0.01; HR=7.620, 95% CI: 3.037-19.121), micropapillary or solid component (P < 0.05; HR= 1.776, 95% CI: 1.010-3.122), lymphovascular invasion (P < 0.05; HR=2.981, 95% CI: 1.198-7.419), and adjuvant therapy (P < 0.01) were independent predictors of DFS. The most common adverse effects included rashes, paronychia, and diarrhea for TKIs and hematological suppression and gastrointestinal reactions for chemotherapy, and TKIs were associated with a higher incidence of grade 3 or above adverse effects (44.4% vs 9.0%).

CONCLUSION

Adjuvant therapy with TKIs helps improve DFS in patients with stage IB (T3-4cmN0M0) lung adenocarcinoma but not in patients with T2ViscPlN0M0. Adjuvant chemotherapy does not improve DFS or OS in patients with stage IB lung adenocarcinoma.

Prognostic impact of spread through air spaces in patients with ≤2 cm stage IA lung adenocarcinoma

Background

In 2015, the World Health Organization (WHO) included spread through air space (STAS) as a new invasive mode of lung cancer. As a new mode of lung cancer dissemination, STAS has a significant and negative impact on patient prognosis. The surgical approach as well as lymph node dissection (LND) for STAS-positive patients is currently unclear. The aim of this study was to investigate the impact of different surgical approaches to STAS and LND on the prognosis of patients with ≤2 cm stage IA lung adenocarcinoma (LUAD). This study also investigated the possible relationship between STAS and the micropapillary histological subtype and its impact on patient prognosis.

Methods

A total of 212 patients with LUAD were included in this study from January 2016 to December 2017, and the overall survival (OS) of the patients was compared. The chi-square test and t-test were applied to compare the clinicopathological data of the patients, and the Cox model was used for the multivariate survival analysis.

Results

Of the 212 patients, 93 (43.9%) were STAS positive. The univariate analysis showed that the surgical approach, LND type, micropapillary pattern (MP), solid pattern, and STAS were risk factors for OS. The multivariate analysis showed that the surgical approach, MP, and STAS were risk factors for OS. The STAS-positive patients who underwent lobectomy had a better prognosis than those who underwent sublobar resection; however, there was no significant difference between the two surgical procedures in the STAS-negative group. Additionally, the STAS-positive patients who underwent systematic lymph node dissection (SLND) had a better prognosis than those who underwent limited lymph node dissection (LLND); however, there was no significant difference between the two LNDs in the STAS-negative group.

Conclusions

STAS plays an important role in patient prognosis and is an independent risk factor for OS of patients with ≤2 cm stage IA LUAD. When STAS is positive, the choice of lobectomy with SLND may result in a better long-term prognosis for patients.

The effect of spread through air spaces on postoperative recurrence-free survival in patients with multiple primary lung cancers

PURPOSE

The purpose of the study was to investigate the effect of spread through air spaces (STAS) on the postoperative prognosis of patients with multiple primary lung cancers staged from IA to IB based on tumor size.

METHODS

Clinicopathological and follow-up data of 122 patients with multiple primary lung cancers diagnosed at stages IA-IB and surgically treated at the Department of Thoracic Surgery, Shenzhen people's Hospital from January 2019 to December 2021 were retrospectively analyzed. The study involved 42 males and 80 females. STAS status was used to divide them into two groups (87 cases in STAS (-) and 35 cases in STAS (+)). A logistic regression analysis, univariate and multivariate Cox regression analysis, and Kaplan-Meier curves (K-M) were used to determine how STAS affected recurrence-free survival (RFS) in patients.

RESULTS

STAS (+) had a significantly higher recurrence rate than STAS (-). STAS was predicted by smoking history (P = 0.044), main tumor diameter (P = 0.02), and solid nodules on chest CT (P = 0.02). STAS incidence was not significantly different between lobectomy and sublobar resection groups (P = 0.17). Solid nodules on CT, tumor diameter, vascular invasion, pleural invasion, and STAS were significant predictors of recurrence in the univariate Cox regression analysis. Tumor diameter, pleural invasion and STAS were significant prognostic factors for recurrence in the multivariate Cox regression analysis. Furthermore, STAS (+) group was at greater risk of recurrence than STAS (-) group (34% vs. 0%, P < 0.05)。.

CONCLUSION

Stage IA-IB multiple primary lung cancer patients with STAS (+) had a higher recurrence rate and a shorter overall survival rate.

A gene-based score for the risk stratification of stage IA lung adenocarcinoma

OBJECTIVE

We aim to molecularly stratify stage IA lung adenocarcinoma (LUAD) for precision medicine.

METHODS

Twelve multi-institution datasets (837 cases of IA) were used to classify the high- and low-risk types (based on survival status within 5 years), and the biological differences were compared. Then, a gene-based classifying score (IA score) was trained, tested and validated by several machine learning methods. Furthermore, we estimated the significance of the IA score in the prognostic assessment, chemotherapy prediction and risk stratification of stage IA LUAD. We also developed an R package for the clinical application. The SEER database (15708 IA samples) and TCGA Pan-Cancer (1881 stage I samples) database were used to verify clinical significance.

RESULTS

Compared with the low-risk group, the high-risk group of stage IA LUAD has obvious enrichment of the malignant pathway and more driver mutations and copy number variations. The effect of the IA score on the classification of high- and low-risk stage IA LUAD was much better than that of classical clinicopathological factors (training set: AUC = 0.9, validation set: AUC = 0.7). The IA score can significantly predict the prognosis of stage IA LUAD and has a prognostic effect for stage I pancancer. The IA score can effectively predict chemotherapy sensitivity and occult metastasis or invasion in stage IA LUAD. The R package IAExpSuv has a good risk probability prediction effect for both groups and single stages of IA LUAD.

CONCLUSIONS

The IA score can effectively stratify the risk of stage IA LUAD, offering good assistance in precision medicine.

Value of adjuvant chemotherapy for patients with pT2N0M0 non-small cell lung cancer receiving radical resection

BACKGROUND

Associations between adjuvant chemotherapy (ACT) and the improvement in survival for patients with pT2N0M0 non-small cell lung cancer (NSCLC) who received R0 resection remain controversial. This study aimed to evaluate the value of ACT for patients with pT2N0M0 NSCLCs, and to identify the subgroups who could benefit from ACT.

METHODS

Multivariable Cox proportional hazards regression models were used to estimate independent prognostic factors. High-risk factor (HRF) included visceral pleural invasion (VPI), lymphovascular invasion (LVI) and poor differentiation/undifferentiated tumors.

RESULTS

Of the 899 patients, 277 (30.8%) patients received ACT. More younger patients (p < 0.001) and male patients (p = 0.007) received ACT. With the increase of pathological tumor size (p < 0.001) and the number of HRFs (p < 0.001), there was a significant rise in the proportion of patients receiving ACT. For all patients, ACT could not improve recurrence-free survival (RFS) (p = 0.672) and overall survival (OS) (p = 0.306). For patients with pathological stage IIA or radiological pure-solid tumors, ACT could significantly improve the OS (p = 0.011 and p = 0.037, respectively), and multivariate analysis revealed that ACT was an independent prognostic factor for patients with pathological stage IIA (p = 0.005). ACT could improve the OS significantly in patients with pathological stage IB pure-solid lung adenocarcinoma (LUAD) (p = 0.043).

CONCLUSION

ACT was valuable for patients with pathological stage IIA (pT2bN0M0) and patients with radiological pure-solid LUAD of pathological stage IB. A combination of radiological features and pathological subtypes could be helpful when selecting patients with pT2N0M0 NSCLCs for ACT.

Micropapillary or solid component predicts worse prognosis in pathological IA stage lung adenocarcinoma: A meta-analysis

BACKGROUND

Micropapillary and solid patterns indicate worse survival in lung adenocarcinoma patients, even in pathological stage IB patients. However, whether the presence of micropapillary or solid components is related to worse prognosis in pathological IA stage lung adenocarcinoma remains unclear.

METHODS

Several databases were searched up to December 31, 2022 for relevant studies investigating the association between micropapillary and solid components and the survival of IA stage lung adenocarcinoma patients. Primary and secondary outcomes are disease-free survival (DFS) and overall survival (OS), respectively. Hazard ratios (HRs) and 95% confident intervals (CIs) were combined, and subgroup analysis stratified by the pathological subtype and proportion of components was further performed.

RESULTS

A total of 19 studies with 12,562 cases were included. Pooled results indicated that micropapillary or solid components obviously predicted worse DFS (HR = 2.40, 95% CI: 1.96-2.94, P < .001) and OS (HR = 2.30, 95% CI: 1.68-3.15, P < .001). Subgroup analysis based on pathological subtype showed that both micropapillary and solid components were significantly associated with worse DFS (micropapillary: HR = 2.70, 95% CI: 1.70-4.28, P < .001; solid: HR = 3.98, 95% CI: 2.10-7.54, P < .001) and OS (micropapillary: HR = 2.29, 95% CI: 1.17-4.48, P = .015; solid: HR = 4.18, 95% CI: 1.72-10.17, P = .002). In addition, further subgroup analysis stratified by the proportion of micropapillary and solid components (>5%/1% or predominant) showed similar results.

CONCLUSION

Micropapillary and solid patterns predicted a significantly worse prognosis in pathological IA stage lung adenocarcinoma patients.

High-risk characteristics of pathological stage I lung adenocarcinoma after resection: patients for whom adjuvant chemotherapy should be performed

Background

The objective of the present study was to identify patients with pathologic stage I lung adenocarcinoma (LUAD) who are at high risk of recurrence and assess the efficacy of adjuvant chemotherapy (ACT) in these individuals.

Methods

A retrospective study was conducted on 1504 patients with pathologic stage I LUAD who underwent surgical resection at Shanghai Pulmonary Hospital and Sun Yat-sen University Cancer Center. Cox proportional hazard regression analyses were performed to identify indicators associated with a high risk of recurrence, while the Kaplan-Meier method and Log-rank test were employed to compare recurrence-free survival (RFS) and overall survival (OS) between patients with ACT and those without it.

Results

Four independent indicators, including age (≥62 years), visceral pleural invasion (VPI), predominant pattern (micropapillary/solid), and lymphovascular invasion (LVI), were identified to be significantly related with RFS. Subsequently, patients were classified into high-risk and low-risk groups by LVI, VPI, and predominant pattern. The administration of ACT significantly increased both RFS (P < 0.001) and OS (P = 0.03) in the high-risk group (n = 250). Conversely, no significant difference was observed in either RFS (P = 0.45) or OS (P = 0.063) between ACT and non-ACT patients in the low-risk group (n = 1254).

Conclusions

Postoperative patients with stage I LUAD with factors such as LVI, VPI, and micropapillary/solid predominant pattern may benefit from ACT.

Prognostic assessment of lung adenocarcinoma patients with early-staging diseases: a nomogram based on coagulation-related factors

OBJECTIVES

Early-stage lung adenocarcinoma (ADC) has a great heterogeneity in prognosis that is difficult to evaluate effectively. Thus, we developed and validated an effective nomogram prognostic model based on the clinical and laboratory characteristics of stage I-IIA ADC.

METHODS

We included 1585 patients with pathologically diagnosed stage I-IIA ADC who underwent surgery at Shanghai Pulmonary Hospital. The nomogram was constructed based on the peripheral blood test and coagulation test indicators and evaluated using Calibration plots, concordance index, decision curve analysis and the X-tile software. Recurrence-free survival (RFS) and overall survival (OS) were estimated by the Kaplan-Meier method and the Cox proportional hazard regression model. The primary end point of this study was RFS.

RESULTS

Thrombin time and 4 clinical indicators for RFS were integrated into nomograms. A favourable agreement between the nomogram prediction and validation was observed in the calibration curves for RFS probabilities. The concordance index of the nomogram to predict RFS was 0.736 (95% confidence interval, 0.717-0.755). Moreover, significant differences were shown between the high-risk and low-risk groups in RFS and OS (P < 0.001) after effective cut-off values of risk points were found based on the nomogram.

CONCLUSIONS

We established and validated a prognostic nomogram including thrombin time to predict RFS and OS of stage I-IIA ADC patients. This nomogram provided an effective prediction ability for the prognosis of stage I-IIA ADC patients.

Prognostic significance of limited resection in pathologic stage I lung adenocarcinoma with spread through air spaces

Background

Tumor spread through air spaces (STAS) is now recognized as tumor invasion. However, the association between STAS and procedure-specific outcomes (limited resection and lobectomy) in patients with pathologic stage I lung adenocarcinoma (ADC) is still under investigation.

Methods

To investigate whether limited resection predicts poorer survival in such patients, we retrospectively analyzed the clinicopathologic features of a large cohort of 1,566 patients with stage I ADC from 2017 to 2020 and classified them according to STAS status and surgical method. Kaplan-Meier, Cox hazard proportional regression, and propensity score matching (PSM) were adopted for prognostic evaluation.

Results

STAS-positive patients had worse recurrence-free survival (RFS) (P<0.001). There was no significant difference in RFS and overall survival (OS) between limited resection and lobectomy, neither for the STAS-negative nor STAS-positive group before matching. After matching, limited resection was found to achieve comparable RFS to lobectomy in STAS-positive patients with pathologic I, IA, or IB stage tumor, (P=0.816, P=0.576, P=0.281, respectively), but worse OS in stage I and stage IB patients (P=0.029, P=0.010, respectively). Furthermore, in multivariable analysis, limited resection was not an independent prognostic factor of RFS or OS. Instead, the high-grade histological subtype was the only independent prognostic factor for RFS (P=0.001). In the subgroup analysis, adjuvant chemotherapy (ACT) did not improve the outcomes of stage IB STAS-positive patients.

Conclusions

Limited resection was associated with worse survival than lobectomy in stage I STAS-positive patients, but not in stage IA STAS-positive patients.

A Novel Systematic Oxidative Stress Score Predicts the Survival of Patients with Early-Stage Lung Adenocarcinoma

This study aimed to construct an effective nomogram based on the clinical and oxidative stress-related characteristics to predict the prognosis of stage I lung adenocarcinoma (LUAD). A retrospective study was performed on 955 eligible patients with stage I LUAD after surgery at our hospital. The relationship between systematic-oxidative-stress biomarkers and the prognosis was analyzed. The systematic oxidative stress score (SOS) was established based on three biochemical indicators, including serum creatinine (CRE), lactate dehydrogenase (LDH), and uric acid (UA). SOS was an independent prognostic factor for stage I LUADs, and the nomogram based on SOS and clinical characteristics could accurately predict the prognosis of these patients. The nomogram had a high concordance index (C-index) (0.684, 95% CI, 0.656–0.712), and the calibration curves for recurrence-free survival (RFS) probabilities showed a strong agreement between the nomogram prediction and actual observation. Additionally, the patients were divided into two groups according to the cut-off value of risk points based on the nomogram, and a significant difference in RFS was observed between the high-risk and low-risk groups (p < 0.0001). SOS is an independent prognostic indicator for stage I LUAD. These things considered, the constructed nomogram based on SOS could accurately predict the survival of those patients.

Surgically Treated pT2aN0M0 (Stage IB) Non-Small Cell Lung Cancer: A 20-Year Single-Center Retrospective Study

Introduction The suitability of adjuvant therapy (AT) in patients with stage IB non-small cell lung cancer (NSCLC) is still under debate considering the cost-benefit ratio between improvement in survival and side effects. We retrospectively evaluated survival and incidence of recurrence in radically resected stage IB NSCLC, to determine whether AT could significantly improve prognosis. Methods Between 1998 and 2020, 4692 consecutive patients underwent lobectomy and systematic lymphadenectomy for NSCLC. Two hundred nineteen patients were pathological T2aN0M0 (>3 and ≤4 cm) NSCLC 8th TNM. None received preoperative or AT. Overall survival (OS), cancer specific survival (CSS) and the cumulative incidence of relapse were plotted and log-rank or Gray's tests were used to assess the difference in outcome between groups. Results The most frequent histology was adenocarcinoma (66.7%). Median OS was 146 months. The 5-, 10-, and 15-year OS rates were 79%, 60%, and 47%, whereas the 5-, 10-, and 15-year CSS were 88%, 85%, and 83%, respectively. OS was significantly related to age (p < 0.001) and cardiovascular comorbidities (p = 0.04), whereas number of LNs removed was an independent prognostic factor of CSS (p = 0.02). Cumulative incidence of relapse at 5-, 10-, and 15-year were 23%, 31%, and 32%, respectively, and significantly related to the number of LNs removed (p = 0.01). Patients with more than 20 LNs removed and clinical stage I had a significantly lower relapse (p = 0.02). Conclusions Excellent CSS, up to 83% at 15-year, and relatively low risk of recurrence for stage IB NSCLC (8th TNM) patients suggested that AT for those patients could be reserved only for very selected high-risk cases.

Impact of surgery and adjuvant chemotherapy on the survival of stage I lung adenocarcinoma patients with tumor spread through air spaces

OBJECTIVES

Tumor spread through air spaces (STAS) is a unique mechanism of lung cancer metastasis; however, its clinical value for stage I lung adenocarcinoma (ADC) remains unclear at present. We investigated the (1) prognosis of patients after sublobar resection compared with lobectomy for stage I lung adenocarcinoma with STAS; and (2) potential benefits of adjuvant chemotherapy (ACT) for patients with stage I ADC and STAS.

METHODS

A total of 3328 consecutive patients with stage I ADC were retrospectively identified between 2014 and 2018 at our institution; among them, 600 were diagnosed with STAS. Kaplan-Meier analysis and Cox proportional hazard regression models were used to evaluate the impact of STAS on overall survival (OS) and recurrence-free survival (RFS).

RESULTS

Among stage IA patients with STAS, there was no significant difference between those who underwent sublobar resection and lobectomy in OS (P = 0.919) and RFS (P = 0.066). Multivariate analysis confirmed this result (sublobar resection versus lobectomy, OS: HR = 0.523, 95 % CI, 0.056-18.458, P = 0.714; RFS, HR = 0.360, 95 % CI, 0.115-1.565, P = 0.897). ACT did not improve the prognosis of stage IA patients but did improve the RFS of stage IB patients with high-risk recurrence factors, including poorly differentiated tumors, lymphovascular invasion and visceral pleural invasion (P = 0.046).

CONCLUSIONS

Sublobar and lobectomy resection provided a comparable prognosis for stage IA ADC patients with STAS. When STAS was confirmed postoperatively, ACT should be considered for patients with stage IB with high-risk recurrence factors but not for those with stage IA disease.

A combined preoperative red cell distribution width and carcinoembryonic antigen score contribute to prognosis prediction in stage I lung adenocarcinoma

AIMS

Hematological markers that can be used for prognosis prediction for stage I lung adenocarcinoma (LUAD) are still lacking. Here, we examined the prognostic value of a combination of the red cell distribution width (RDW) and carcinoembryonic antigen (CEA), namely, the RDW-CEA score (RCS), in stage I LUAD.

MATERIALS AND METHODS

A retrospective study with 154 patients with stage I LUAD was conducted. Patients were divided into RCS 1 (decreased RDW and CEA), RCS 2 (decreased RDW and increased CEA, increased RDW and decreased CEA), and RCS 3 (increased RDW and CEA) subgroups based on the best optimal cutoff points of RDW and CEA for overall survival (OS). The differences in other clinicopathological parameters among RCS subgroups were calculated. Disease-free survival (DFS) and OS among these groups were determined by Kaplan-Meier analysis, and risk factors for outcome were calculated by a Cox proportional hazards model.

RESULTS

Seventy, 65, and 19 patients were assigned to the RCS 1, 2, and 3 subgroups, respectively. Patients ≥ 60 years (P < 0.001), male sex (P = 0.004), T₂ stage (P = 0.004), and IB stage (P = 0.006) were more significant in the RCS 2 or 3 subgroups. The RCS had a good area under the curve (AUC) for predicting DFS (AUC = 0.81, P < 0.001) and OS (AUC = 0.93, P < 0.001). The DFS (log-rank = 33.26, P < 0.001) and OS (log-rank = 42.05, P < 0.001) were significantly different among RCS subgroups, with RCS 3 patients displaying the worst survival compared to RCS 1 or 2 patients. RCS 3 was also an independent risk factor for both DFS and OS.

CONCLUSIONS

RCS is a useful prognostic indicator in stage I LUAD patients, and RCS 3 patients have poorer survival. However, randomized controlled trials are needed to validate our findings in the future.

Retrospective analysis of the prognostic implications of tumor spread through air spaces in lung adenocarcinoma patients treated with surgery

Background

Tumor spread through air spaces (STAS) in lung adenocarcinoma is a novel mechanism of invasion. STAS has been proposed as an independent predictor of poor prognosis. The aim of this study was to evaluate the correlations between STAS status and other clinicopathologic variables and to assess the prognostic implications of STAS and the distance from the edge of the tumor to the farthest STAS in patients with resected lung adenocarcinoma.

Material and methods

This is a single-institution retrospective observational study. We included all patients with resected lung adenocarcinoma from January 2017 to December 2018 at La Paz University Hospital. The cut-off for the distance from the edge of the tumor to the farthest STAS was 1.5 mm and was assessed by the area under the receiver operating characteristic curve.

Results

A total of 73 patients were included. STAS was found in 52 patients (71.2%). Histological grade 3 (P = 0.035) and absence of lepidic pattern (P = 0.022) were independently associated with the presence of STAS. The median recurrence-free survival (RFS) was 48.06 months [95% confidence interval (CI) 33.58 months to not reached]. STAS-positive patients had shorter median RFS [39.23 months (95% CI 29.34-49.12 months)] than STAS-negative patients (not reached) (P = 0.04). STAS-positive patients with a distance from the edge of the tumor to the farthest STAS ≥1.5 mm had an even shorter median RFS [37.63 months (95% CI 28.14-47.11 months)]. For every 1 mm increase in distance, the risk of mortality increased by 1.26 times (P = 0.04).

Conclusions

Histological grade 3 and absence of lepidic pattern were independently associated with the presence of STAS. STAS was associated with a higher risk of recurrence. The distance from the edge of the tumor to the farthest STAS also had an impact on overall survival.

•

Lung adenocarcinoma patients with STAS had higher risk of recurrence.

•

Patients with STAS and a distance from the edge of the tumor to the farthest STAS ≥1.5 mm had an even shorter RFS.

•

The distance from the edge of the tumor to the farthest STAS also had an impact on overall survival.

[A Review on Pathological High-risk Factors and Postoperative Adjuvant Chemotherapy in Stage IA Lung Adenocarcinoma]

The survival rate needs to be improved in early stage non-small cell lung cancer patients. The risk of recurrence is relatively high in invasive adenocarcinoma patients with a solid or micropapillary component, lymphovascular invasion or tumor spread through air spaces. Systemic treatment options including radical surgical resection should be explored for this population. Adjuvant chemotherapy is not recommended for patients in stage IA in current guidelines. This article is a review on the research progress of the above pathological high-risk factors and the role of adjuvant chemotherapy in patients with pathological high-risk factors in stage IA lung adenocarcinoma.
.

Adjuvant chemotherapy can benefit the survival of stage I lung adenocarcinoma patients with tumour spread through air spaces after resection: Propensity-score matched analysis

Background

It is still unclear whether stage I lung adenocarcinoma patients with tumour spread through air spaces (STAS) can benefit from postoperative adjuvant chemotherapy (ACT) after lobectomy. This study investigated the effect of ACT on the postoperative survival of patients with stage I (STAS⁺) lung adenocarcinoma.

Methods

We retrospectively analysed the clinical data of stage I (STAS⁺) invasive lung adenocarcinoma patients who underwent lobectomy in the Department of Thoracic Surgery of our hospital from January 1, 2013 to January 1, 2016. Propensity score matching (PSM) was performed to group patients to investigate whether ACT could lead to better prognosis of patients.

Results

A total of 593 patients with stage I (STAS⁺) lung adenocarcinoma were enrolled. The study after PSM included 406 patients. Kaplan–Meier survival analysis showed the experimental group had a better 3-year recurrence-free survival (RFS) rate (p = 0.037) and the 5-year RFS rate (p = 0.022) than the control group. It also had higher 5-year overall survival (p = 0.017). The multivariate analysis by Cox proportional hazard regression model showed that stage I STAS⁺ lung adenocarcinoma patients with lymphatic vessel invasion (HR: 1.711, 95% CI: 1.052-2.784; p = 0.045), vascular invasion (HR: 5.014, 95% CI: 3.154-7.969; p < 0.001), and visceral pleural invasion (HR: 2.086, 95% CI: 1.162-3.743; p = 0.014), and without ACT (HR: 1.675, 95% CI: 1.043-2.689; p = 0.033) had a significant survival disadvantage.

Conclusion

ACT can boost the postoperative survival of patients with stage I (STAS⁺) lung adenocarcinoma.

Clinicopathological Impact of the Spread through Air Space in Non-Small Cell Lung Cancer: A Meta-Analysis

This study aimed to elucidate the clinicopathological significance of spread through air space (STAS) in non-small cell lung cancer (NSCLC) through a meta-analysis. Using 47 eligible studies, we obtained the estimated rates of STAS in various histological subtypes of NSCLC and compared the clinicopathological characteristics and prognosis between NSCLC with and without STAS. The estimated STAS rate was 0.368 (95% confidence interval [CI], 0.336–0.0.401) in patients with NSCLC. Furthermore, the STAS rates for squamous cell carcinoma and adenocarcinoma were 0.338 (95% CI, 0.273–0.411) and 0.374 (95% CI, 0.340–0.409), respectively. Among the histological subtypes of adenocarcinoma, micropapillary-predominant tumors had the highest rate of STAS (0.719; 95% CI, 0.652–0.778). The STAS rates of solid- and papillary-predominant adenocarcinoma were 0.567 (95% CI, 0.478–0.652) and 0.446 (95% CI, 0.392–0.501), respectively. NSCLCs with STAS showed a higher visceral pleural, venous, and lymphatic invasion than those without STAS. In addition, anaplastic lymphoma kinase mutations and ROS1 rearrangements were significantly more frequent in NSCLCs with STAS than in those without STAS. The presence of STAS was significantly correlated with worse overall and recurrence-free survival (hazard ratio, 2.119; 95% CI, 1.811–2.480 and 2.372; 95% CI, 2.018–2.788, respectively). Taken together, the presence of STAS is useful in predicting the clinicopathological significance and prognosis of patients with NSCLC.

Ground Glass Opacity and Adjuvant Chemotherapy in Pathological Stage IB-IIA Lung Adenocarcinoma

Background

The prognostic value of ground glass opacity (GGO) in stage IA non-small cell lung cancer (NSCLC) has been widely recognized. However, studies investigating its value in the related stage IB-IIA lung adenocarcinoma (LUAD) remains lacking. The impact of adjuvant chemotherapy (ACT) on pathological stage IB-IIA LUAD is also controversial.

Materials and Methods

We retrospectively reviewed the clinical records of 501 patients with pathological stage IB-IIA LUAD at the Sun Yat-sen University Cancer Center from January 2008 to June 2018. We calculated and compared survival curves using the Kaplan-Meier test and log-rank test. Cox regression models were performed to determine independent prognostic factors of disease-free survival (DFS) and overall survival (OS). We established nomograms to predict the OS and DFS of LUAD patients. Calibration and receiver operator characteristic curves were conducted to assess the predictive performance of two nomograms. Based on the nomogram, we identified candidate patients that may most benefit from ACT after surgery.

Results

The number of patients with pure solid, part GGO, and pure GGO nodules was 240, 242, and 19, respectively, and 125 patients who received ACT. Patients with consolidation-to-tumor ratio (CTR) <0.75 had longer OS (P = 0.026) and DFS (P = 0.003). Pathological tumor size and at least 10 lymph nodes (LNs) resection were independent prognostic factors of both OS and DFS. CTR <0.75 was positively associated with DFS. The C-index of nomograms predicting individual OS and DFS was 0.660 and 0.634, respectively. Based on the nomogram for OS, ACT was found to be a positive prognostic indicator of OS (P = 0.031, HR = 0.5141, 95% CI 0.281-0.942) in patients with nomogram total points ≥5.

Conclusion

CTR <0.75 is associated with a better DFS in patients with stage IB-IIA LUAD. Nomograms developed by integrating pathological tumor size, at least 10 LNs resection, and CTR ≥0.75 for predicting individual OS and DFS displayed a good predictive capacity and clinical value, which were also proved to be a useful tool for selecting patients most benefiting from ACT.

Pretreatment prediction of tumour spread through air spaces in clinical stage I non-small cell lung cancer

OBJECTIVES

To construct a nomogram prediction model for tumour spread through air spaces (STAS) in clinical stage I non-small cell lung cancer (NSCLC) and discuss its potential application value.

METHODS

380 patients with clinical stage I NSCLC in Tianjin Chest Hospital were collected as the training cohort and 285 patients in Fujian Provincial Hospital were collected as the validation cohort. Univariable and multivariable logistic regression analyses were performed to determine independent factors for STAS in the training cohort. Based on the results of the multivariable analysis, the nomogram prediction model of STAS was constructed by R software.

RESULTS

The incidence of STAS in the training cohort was 39.2%. STAS was associated with worse overall survival and recurrence-free survival (P<0.01). Univariable analysis showed that maximum tumour diameter (Tdmax), consolidation-to-tumour ratio (CTR), spiculation, vacuole and carcinoembryonic antigen were associated with STAS (P<0.05). Multivariable analysis showed that Tdmax, CTR, spiculation sign, and vacuole were independent risk factors for STAS (P<0.05). Based on this, the nomogram prediction model of STAS in clinical stage I NSCLC was constructed and internally validated by bootstrap. The Hosmer-Lemeshow test showed a χ2 value of 7.218 (P=0.513). The area under the ROC curve (AUC) and C-index were 0.724 (95% CI: 0.673-0.775). The external validation conducted on validation cohort produced an AUC of 0.759 (95% CI: 0.703-0.816).

CONCLUSIONS

The constructed nomogram prediction model of STAS in clinical stage I NSCLC has good calibration and can potentially be applied to guide treatment selection.

Percentage of Newly Proposed High-Grade Patterns Is Associated with Prognosis of Pathological T1-2N0M0 Lung Adenocarcinoma

OBJECTIVE

To evaluate the prognostic value of the percentage of high-grade patterns (micropapillary, solid, and complex glands) in early-stage lung adenocarcinoma (LUAD).

METHODS

A total of 1049 patients undergoing radical surgery with pathological T1-2N0M0 LUAD were screened retrospectively, and 191 patients were involved in the final analysis. Disease-free survival (DFS) was evaluated using the Kaplan-Meier curve and Cox regression analysis. The optimal cut-off value was determined using maximally selected rank statistics.

RESULTS

The entire cohort was divided into quartile groups based on the percentage of high-grade patterns: Group 1 (≤ 30%), Group 2 (31-55%), Group 3 (56-85%), and Group 4 (≥ 86%). There were significant differences in smoking history (P = 0.041), EGFR mutations (P < 0.001), and ALK rearrangement (P = 0.010) between the four groups, but no significant differences in other clinicopathological features. Kaplan-Meier analysis showed that a higher percentage of high-grade patterns predicted worse DFS (P = 0.001), and multivariate analysis indicated that the percentage of high-grade patterns was an independent predictor (Group 2 vs. Group 1, HR = 2.136, P = 0.228; Group 3 vs. Group 1, HR = 3.355, P = 0.035; Group 4 vs. Group 1, HR = 5.147, P = 0.003, respectively). A cut-off value of 20% (P = 0.048) and 50% (P <0.001) for high-grade patterns were tested, and both revealed a significant difference in distinguishing DFS between subgroups.

CONCLUSIONS

The percentage of high-grade patterns is associated with the prognosis of early-stage invasive LUAD. A higher percentage indicates a worse prognosis.

The prognostic significance of tumor spread through air space in stage I lung adenocarcinoma

Aim

There are still patients of stage I lung adenocarcinoma (ADC) suffering from local or distant recurrence. Herein we conducted a meta‐analysis to investigate the prognostic value of tumor spread through air space (STAS), a new form of invasion pattern, in patients with pathologically confirmed stage I lung ADC.

Methods

Related literature was searched using PubMed, Embase, Cochrane Library, and Web of Science databases from the inception dates to September 4, 2021. Recurrence‐free survival (RFS) and overall survival (OS) were set as primary outcome endpoints. In addition, subgroup analyses on operation mode, edition of the American Joint Committee on Cancer TNM staging, sample size, and research regions were also investigated.

Results

A total of 17 studies involving 9785 patients were included. The presence of STAS was detected in 31.2% of patients and was associated with poor RFS (adjusted hazard ratio [HR] = 1.93, p < 0.001) and OS (HR = 2.02, p < 0.001). In subgroup analysis on operation mode, the prognostic value of STAS was prominently shown in patients who underwent limited resection (RFS: HR = 3.58, p < 0.001; OS: HR = 3.37, p < 0.001), while for patients who underwent lobectomy, adverse impact of STAS on RFS was observed (HR = 1.60, p = 0.019), but no significant difference was observed on OS (HR = 1.56, p = 0.061). The results fluctuated in different regions while other factors did not alter the independent predictive value of STAS.

Conclusion

Tumor STAS should be considered as an adverse prognostic indicator for patients with stage I lung ADC, especially for those under limited resection. More intensive medical care for those patients needs to be investigated in further studies.

Benefit of adjuvant chemotherapy for patients with stage IB non-small cell lung cancer: a systematic review and meta-analysis

Background

Adjuvant chemotherapy (ACT) is routinely the recommended treatment for patients with advanced non-small cell lung cancer (NSCLC) but remains a controversial option in stage IB patients. We therefore pooled the current evidence to determine the prognostic impact of ACT in stage IB NSCLC patients in the context of the eighth tumor, node, metastasis (TNM) staging system.

Methods

Five electronic databases were searched for eligible studies up to December 2020 without language restrictions. The primary and secondary outcomes were overall survival (OS) and disease-free survival (DFS). Search results were filtered by a set of eligibility criteria and analyzed in line with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The risk of bias was assessed independently using a modified set. Stata 16.0 was used for general data analysis and meta-analysis, and subgroup analyses were performed to investigate the source of interstudy heterogeneity.

Results

In all, 12 eligible studies were identified and 15,678 patients included. Our results demonstrated that ACT was associated with improved OS [n=11; hazard ratio (HR) =0.65; 95% confidence interval (CI): 0.60–0.70; P<0.001; I²=33.4%, P=0.131] and DFS (n=9; HR =0.73; 95% CI: 0.63–0.83; P<0.001; I²=66.7%, P=0.002) in stage IB NSCLC patients. Subgroup analysis by histology indicated that administration of ACT conferred more favorable survival to both stage IB squamous cell carcinoma (n=1; HR =0.56; 95% CI: 0.28–0.84; P<0.001) and adenocarcinoma (n=6; HR =0.59; 95% CI: 0.47–0.71; P<0.001; I²=31.0%, P=0.203). Meanwhile, both platinum-based ACT (n=7; HR =0.62; 95% CI: 0.51–0.74; P<0.001; I²=44.8%, P=0.093) and other regimens (n=2; HR =0.66; 95% CI: 0.61–0.72; P<0.001; I²=0.7%, P=0.316) could benefit patients with stage IB disease.

Discussion

ACT might provide survival benefits to patients with stage IB NSCLC irrespective of histology or regimens. Patient selection and time trend biases were inevitable due to the limitation of retrospective studies. More prospective studies should be initiated to investigate the optimal ACT regimens in different histologic types in stage IB NSCLC patients.

Spread Through Air Spaces (STAS) in Non-Small Cell Lung Carcinoma: Evidence Supportive of an In Vivo Phenomenon

Tumor spread through air spaces (STAS) is associated with locoregional recurrence in patients undergoing limited resection (LR) for non-small cell lung carcinoma (NSCLC). We hypothesized that the observation of STAS in both the initial LR specimen and the additional resection specimen from the same patient, processed using different knives, would provide evidence that STAS is an in vivo phenomenon contributing to locoregional recurrence. We retrospectively identified patients with NSCLC (9 adenocarcinoma, 1 squamous cell carcinoma) who underwent LR, had STAS in the LR specimen, and underwent additional resection (lobectomy or LR). The LR and additional resection specimens from each patient were processed at different times using different tissue-processing knives. All specimens were analyzed for STAS. All 10 patients underwent LR with negative margins (R0). All additional resection specimens had STAS: 8 patients had STAS clusters in their completion lobectomy specimens, and 2 had STAS in their additional LR specimens. In 2 patients, STAS was found in the completion lobectomy specimen only after extensive sampling (>10 sections) from the staple line adjacent to the initial LR. The presence of STAS in both the LR and the additional resection specimen processed using different knives supports the concept that STAS is an in vivo phenomenon, rather than an artifact from tissue processing. This observation indicates that occult STAS tumor cells can be present in the lung tissue of the remaining unresected lobe after LR and supports the concept that STAS is a contributing factor for locoregional recurrence following LR.

[Progress in Single-cell RNA Sequencing of Lung Adenocarcinoma]

肺腺癌（lung adenocarcinoma, LUAD）是临床上肺癌最常见的亚型，是癌症相关死亡最主要的原因之一。过去十几年中，随着薄层计算机断层扫描（computed tomography, CT）广泛用于常规肺癌筛查，影像学上表现为小结节的LUAD发病率显著增高，其发生发展机制复杂，个体预后差异显著。尽管近年来针对LUAD的靶向和免疫疗法取得了重大进展，但肿瘤细胞的耐药性始终未得到有效解决，从而限制了患者获益。随着人类基因组计划的完成，以测序为基本手段的基因组学及转录组学进入临床和科研人员的视野。单细胞测序作为近年来受到高度关注的新型测序手段，与二代测序相比，其能在单细胞水平上对细胞群体进行特异性分析，揭示出每种细胞类型独特的变化，在单细胞水平上对许多异质基质细胞和癌细胞进行较精准地评估，从而揭示了分子成分的复杂性以及与非恶性组织中相应成分的区别。综上，通过单细胞测序深入了解LUAD发生发展机制和肿瘤微环境（tumor microenvironment, TME）的异质性及其耐药性形成机制，从而发现新的治疗靶点是临床医生和基础科学家迫切的需求。本文综合论述了单细胞测序在LUAD中的具体应用和研究进展。

The prediction of spread through air spaces with preoperative 18F-FDG PET/CT in cases with primary lung adenocarcinoma, its effect on the decision for an adjuvant treatment and its prognostic role

PURPOSE

In lung adenocarcinoma cases, 'spread through air spaces' (STAS) is a new indicator of invasion and directly related to disease survival. The aim of our study is to establish whether a preoperatively performed 18F-Fluorodeoxyglucose (FDG) PET/computed tomography (CT) imaging data can predict the presence of STAS in cases with lung adenocarcinoma and thus predict the decision for the type of surgery and adjuvant chemotherapy.

MATERIALS AND METHODS

Between 2000 and 2019, we retrospectively analyzed 63 patients with lung adenocarcinoma cases that had undergone lobectomy or pneumonectomy. Semiquantitative parameters were calculated and metabolic tumor volume (MTV)/CT volume (CTV) ratio was recorded from FDG PET/CT data. The pathological samples from these patients were evaluated for STAS. All these values were evaluated for their correlation with the alveolar spread.

RESULTS

There was no statistically significant correlation to be found between CTV, MTV, total lesion glycolysis (TLG), standardized uptake value (SUV)max, SUVmean and STAS (P > 0.05). However, MTV/CTV ratio above 1 had statistically more alveolar spread. In the group with an MTV ratio above 1, STAS positivity was 27 (75%), and 9 (25%) did not have STAS, whereas these were 6 (22.2%) patients who had STAS, and 21 (77.8%) did not have STAS in the group with below 1 (P < 0.001).

CONCLUSIONS

In the preoperative PET study inoperable lung adenocarcinoma cases, MTV/CTV ratio higher than 1 was found to predict STAS positivity. As a result, it was found that it provided significant clinical additional information regarding the need for a surgical approach (lobar resection instead of sublobar) and adjuvant chemotherapy.