Comment on an external validation of the 8th edition of the TNM classification for lung cancer staging in patients treated with chemoradiation

Pretreatment systemic inflammation response index (SIRI) is an independent predictor of survival in unresectable stage III non-small cell lung cancer treated with chemoradiotherapy: a two-center retrospective study

Background

Circulating immune cells influence the efficacy of cancer therapy. This study aimed to investigate the prognostic values of different peripheral blood leukocyte (PBL) biomarkers in non-small lung cancer (NSCLC) patients treated with chemoradiotherapy.

Methods

An independent cohort of 176 stage III NSCLC patients who were diagnosed at Shanghai Pulmonary Hospital and Zhejiang Cancer Hospital between April, 2010, and September, 2018, and had available pretreatment peripheral blood tests was enrolled. The patients were all treated with concurrent or sequential chemoradiotherapy according to international clinical guidelines, with conventional fractionated radical radiotherapy. The receiver operating characteristic curve and the Youden index were used to determine the optional cutoff values of PBL biomarkers for distinguishing prognosis. Univariate and multivariate Cox proportional hazards regression analyses were performed to identify the factors significantly correlated with overall survival.

Results

The cohort had a median follow-up time of 21.7 (3.1–121) months. The 3- and 5-year OS rates of all patients were 34.7% and 27.5%, respectively. Univariate analysis showed that gender (P=0.011), smoking (P=0.011), tumor-node-metastasis (TNM) stage (P=0.002), pretreatment peripheral blood neutrophil-to-leukocyte ratio (P=0.013), and systemic inflammation response index (SIRI, P<0.001) were all correlated with OS in NSCLC patients. Moreover, multivariate analysis revealed that TNM stage (HR =1.541, 95% CI: 1.166–2.036, P=0.010) and SIRI (HR =1.868, 95% CI: 1.016–3.436, P=0.018) were significantly and independently associated with OS. However, the median OS of stage IIIB NSCLC patients with low SIRI (≤2.0) was longer than that of stage IIIA NSCLC patients with high SIRI (>2.0) (33.9±4.1 vs. 19.6±2.5 months).

Conclusions

Pretreatment peripheral blood SIRI was found to be a simple independent predictor of OS in stage III NSCLC patients who underwent chemoradiotherapy. As a novel prognostic marker, the prognostic value of the SIRI is superior to that of the NLR. Low SIRI could be a better prognostic stratification factor for NSCLC patients with different TNM stages.

Recommended changes for the 8th edition of the TNM classification for lung cancer-the findings of a single-institution evaluation

BACKGROUND

To evaluate the efficacy of the nodal descriptors and subgroups proposed by International Association for the Study of Lung Cancer (IASLC) in the 8th edition of the TNM classification system and to provide references for future editions.

METHODS

A total of 3,177 patients with non-small cell lung cancer at the Beijing Cancer Hospital were classified based on the following three methods: (I) the N descriptors in the 8th edition of the TNM classification system: N0, N1, N2, and N3; (II) the IASLC-proposed N subgroups: N1a, N1b, N2a1, N2a2, and N2b; (III) our more extensive division method: N1a, N1b, N1c, N2a1, N2a2, N2b1, N2b2, N2c, N3a, and N3b. Five-year survival analysis was performed using the Kaplan-Meier method, and differences between subgroups were evaluated using the log-rank test.

RESULTS

(I) A significant survival difference was found between each adjacent N descriptor; (II) the difference between each adjacent subgroup N descriptor was significant, but the difference between N1b and N2a1 was not; (III) in our proposed method, a significant difference was found between all the subgroups apart from N2a2 and N2b1, N2b1 and N2b2, N2c and N3a, and N3a and N3b.

CONCLUSIONS

The N descriptors in the 8th edition of the tumor, node, and metastasis (TNM) classification system are consistent with our data. Although our more extensive division method could distinguish between patients at different stages, its implementation is complicated; thus, we recommend the implementation of the IASLC-proposed subgroups with the addition of the N1b and N2a1 groups.

External validation of the eighth edition of the TNM classification for lung cancer in 3,611 surgically treated patients at a single institution

BACKGROUND

A new revision of the tumor, node, metastasis (TNM) classification for lung cancer has been proposed by the International Association for the Study of Lung Cancer (IASLC), but external validation for it is required. This study aimed to evaluate stage groupings in the 8th edition of the TNM classification in an independent Chinese cohort.

METHODS

We retrospectively analyzed 3,611 patients who were diagnosed as stage I to IV non-small cell lung cancer (NSCLC) and who received surgical treatment at our institute in China between October 2009 and August 2017. Long-rank tests were used to compare survival between two adjacent stage groups.

RESULTS

Based on the 8th edition of the TNM classification, differences between every 2 adjacent stage groups were found to be significant except between Ia1 and Ia2 (P=0.062), and between IIIc and IVa (P=0.063). Significant differences were found between every 2 adjacent categories stratified by the T and N descriptors. Additionally, significant differences were found between M0 and M1a (P<0.001), while no significant difference was observed between M1a and M1b (P=0.092).

CONCLUSIONS

Our study provides an external validation of the stage groupings in the 8th edition of the TNM staging system in surgically treated Chinese patients with NSCLC.