(015) Discordance between clinical and pathological stage in non-small cell lung cancer patients in China

Background: Accurate staging is conducive to developing the effective medical treatment and predicting patient prognosis for lung cancer patients. The discordance between clinical and pathological stage has been reported to be associated with a worse disease-free survival for lung cancer.

Objectives: To investigate the discordance between clinical and pathological stage in Chinese NSCLC patients in a real-world setting.

Methods: The retrospective cohort study utilized hospital electronic medical records from 2014-2017 from adult patients with NSCLC and undergone curative intent surgery in Ruijin Hospital. The clinical (c-) and pathological (p-) stages were identified according to the eighth edition American Joint Committee on Cancer (AJCC) staging manual. Stage concordance was defined as being assigned to the same stages clinically (from image tests) and pathologically after surgery. Discordance was stratified by upstage (pStage was higher than cStage) and downstage (pStage was higher than cStage). The concordance and discordance rates were calculated for cStages I, II and III, tumor (T) and nodal (N) staging. The Kendall correlation coefficient was used to calculate the correlation of clinical and pathological stages. The Pearson’s correlation coefficient was used to elucidate the correlation between clinical and pathologic tumor size by clinical stage.

Results: A total of 1,238 NSCLC patients were included, with a median age of 62 years (IQR 54, 67 years). Approximately 84.2% of patients were diagnosed with cStage I, 5.9% with cStage II and 9.9% with cStage III. The overall concordance was 77.4%, with a downstage of 14.7% and upstage of 7.9%. The concordance was 83.8%, 49.3% and 39.3% for cStage I, cStage II, and cStage III, respectively. The concordance for T staging was 64.2%, and for cT1-4 stages was 81.9%, 31.5%, 50.0% and 68.0%, respectively. The concordance for N staging was 85.6%, and for cN0 was 93.1%, but for cN1-3 stages was only 20.8%, 25.3% and 0%, respectively. The Kendall correlation coefficient was 0.47 (p < 0.001). The Pearson’s correlation coefficients were 0.80 for cStage I, 0.47 for cStage II and 0.88 for cStage III (all p< 0.001).

Conclusions: The concordance between clinical and pathological stages for NSCLC patients was high for early stages (cStage I, T1 and N0) covering most of the patients, but low for advanced stages (cStage II-III) or for tumors with nodal metastasis. There were significant correlations for tumor size by clinical stages.