Clinical implications and molecular features of tertiary lymphoid structures in stage I lung adenocarcinoma

AIMS

We investigated the clinical implications and molecular features of TLS in stage I lung adenocarcinoma (LUAD).

METHODS

We retrospectively reviewed the clinicopathological characteristics of 540 patients with p-stage I LUAD. Logistic regression analysis was applied to determining the relationships between clinicopathological features and the presence of TLS. TLS-associated immune infiltration pattern and signature genes were characterized using the transcriptomic profiles of 511 LUADs from The Cancer Genome Atlas (TCGA) database.

RESULTS

The presence of TLS was associated with a higher pT stage, low- and middle-grade patterns, and the absence of tumor spreading through air spaces (STAS) and subsolid nodules. Multivariate Cox regression analysis identified that the presence of TLS was associated with favorable overall survival (OS) (p < 0.001) and recurrence-free survival (RFS) (p < 0.001). Subgroup analysis showed that the most favorable OS (p < 0.001) and RFS (p < 0.001) favored the TLS + PD-1- subgroup. The presence of TLS was characterized by abundance in antitumor immunocytes including activated CD8+ T and B cells as well as dentritic cells in TCGA cohort.

CONCLUSION

The presence of TLS was an independent favorable factor for patients with stage I LUAD. The presence TLS was featured by special immune profiles which might aid oncologists in determining personalized adjuvant treatment.

A systematic review and meta-analysis of the influence of STAS on the long-term prognosis of stage I lung adenocarcinoma

Background

The appearance of airway dissemination often indicates poor prognosis of lung cancer. However, the relationship between airway dissemination and early lung adenocarcinoma is not clear. Therefore, this study uses meta-analysis to study the long-term prognosis of patients with early lung adenocarcinoma.

Methods

A computer search of the PubMed, EMbase, Web of Science, and other databases was conducted, and the search time limit was from the establishment of the database to December 30, 2020. Data strictly in accordance with the inclusion and exclusion criteria was extracted and the quality of the included literature was evaluated. Two reviewers then independently screened the literature and evaluated the risk of bias.

Results

A total of 11 studies were included, comprised of 5,097 patients with early lung adenocarcinoma. The results of the meta-analysis showed that among patients with stage I lung adenocarcinoma, the 5-year recurrence-free survival (RFS) and overall survival (OS) of STAS-positive patients was lower than those of the STAS-negative group, and the difference was statistically significant. In the control study, the 5-year RFS was HR =1.95, 95% CI (1.58–2.31) P<0.01, and the 5-year OS was OR =2.04, 95% CI (1.60–2.48) P<0.01, and in STAS-positive patients, sublobectomy had a worse long-term prognosis than lobectomy. While the 5-year RFS HR of the lobectomy group was 1.82, 95% CI (1.43–2.22), and the 5-year RFS HR of the sublobectomy group was 6.92, 95% CI (1.64–12.18) P<0.01, the prognosis of the STAS-positive high-expression group and the low-expression group was worse. The 5-year RFS HR of the low-expression STAS group was 2.93, 95% CI (0.21–6.07), and in the high expression group this was 8.20, 95% CI (0.55–15.85) P<0.05.

Discussion

STAS is an independent risk factor for the poor prognosis of stage I lung adenocarcinoma and a high expression of STAS results in a higher 5-year recurrence rate. When STAS is positive, the sublobectomy method should be carefully selected. However, our research has certain limitations, such as literature selection and publication bias. At the same time, the depth of literature analysis needs to be further improved.

Analysis of risk factors for stage I lung adenocarcinoma using low-dose high-resolution computed tomography

Risk factors for stage I lung adenocarcinoma were analyzed using low-dose high-resolution computed tomography (CT). The patients were divided into case group (stage I lung adenocarcinoma patients) and control group (benign pulmonary nodules patients). All patients were subjected to low-dose high-resolution CT. Multiple linear regression was performed to analyze the CT imaging features of the two groups. Stage I lung adenocarcinoma patients were significantly associated with nodular site (X3, upper left lobe) [95% CI (1.796, 54.695), p=0.008], nodule type (X4) (p<0.001), nodule size (X5) [95% CI (0.614, 0.803), p<0.001], spicule sign (X7) [95% CI (0.029, 0.580), p=0.008], lobulation sign (X8) [95% CI (0.048, 0.673), p=0.011]. The stepwise regression equation is: Logistic (p) =-12.009 + 2.294X3 - 0.327X4 - 0.354X5 - 2.042X7 - 1.713X8. Risk factors of low-dose and high-resolution CT imaging for patients with stage I lung adenocarcinoma are nodular site (upper left lobe), nodule type, nodule size, spicule sign, and lobulation sign.