Is the rate of pneumonectomy higher in right middle lobe lung cancer than in other right-sided locations?

Development and validation of web-based dynamic nomograms predictive of disease-free and overall survival in patients who underwent pneumonectomy for primary lung cancer

Background

The tumour-node-metastasis (TNM) staging system is insufficient to precisely distinguish the long-term survival of patients who underwent pneumonectomy for primary lung cancer. Therefore, this study sought to identify determinants of disease-free (DFS) and overall survival (OS) for incorporation into web-based dynamic nomograms.

Methods

The clinicopathological variables, surgical methods and follow-up information of 1,261 consecutive patients who underwent pneumonectomy for primary lung cancer between January 2008 and December 2018 at Sun Yat-sen University Cancer Center were collected. Nomograms for predicting DFS and OS were built based on the significantly independent predictors identified in the training cohort (n = 1,009) and then were tested on the validation cohort (n = 252). The concordance index (C-index) and time-independent area under the receiver-operator characteristic curve (AUC) assessed the nomogram's discrimination accuracy. Decision curve analysis (DCA) was applied to evaluate the clinical utility.

Results

During a median follow-up time of 40.5 months, disease recurrence and death were observed in 446 (35.4%) and 665 (52.7%) patients in the whole cohort, respectively. In the training cohort, a higher C-reactive protein to albumin ratio, intrapericardial pulmonary artery ligation, lymph node metastasis, and adjuvant therapy were significantly correlated with a higher risk for disease recurrence; similarly, the independent predictors for worse OS were intrapericardial pulmonary artery and vein ligation, higher T stage, lymph node metastasis, and no adjuvant therapy. In the validation cohort, the integrated DFS and OS nomograms showed well-fitted calibration curves and yielded good discrimination powers with C-index of 0.667 (95% confidence intervals CIs [0.610-0.724]) and 0.697 (95% CIs [0.649-0.745]), respectively. Moreover, the AUCs for 1-year, 3-year, and 5-year DFS were 0.655, 0.726, and 0.735, respectively, and those for 3-year, 5-year, and 10-year OS were 0.741, 0.765, and 0.709, respectively. DCA demonstrated that our nomograms could bring more net benefit than the TNM staging system.

Conclusions

Although pneumonectomy for primary lung cancer has brought encouraging long-term outcomes, the constructed prediction models could assist in precisely identifying patients at high risk and developing personalized treatment strategies to further improve survival.

Pulmonary middle lobectomy for non-small-cell lung cancer: effectiveness and prognostic implications

OBJECTIVES

The therapeutic value of pulmonary middle lobectomy (PML) has been questioned. PML is currently regarded as a standard form of lobectomy, even so it shares some surgical features with segmentectomies (SEG) more than with lobectomies. The present study's aim was to assess the therapeutic value of PML with respect to other lobectomies (LOBs) and SEGs.

METHODS

A total of 902 consecutive patients who underwent lobectomy or SEG with mediastinal lymph node dissection for Stage I-IIIa non-small-cell lung cancer were analysed. Patients with pT4 tumours and/or pathologically incomplete resection were excluded.

RESULTS

PML was performed in 50 patients, SEG in 44 and LOBs were performed in 808. The three study groups were homogeneous, except for gender, pT and grade: females, pT1 and G1 tumours were more frequent in the PML and SEG groups. The lymph node dissection yield was poorer in PML (P < 0.007) and SEG (P < 0.001) groups when compared with LOB group. Five-year overall survival (OS) was 45.3% for PML, 54.0% for SEG and 60.2% for LOB (P = 0.793). When limiting the analysis to G2-3 right-sided tumours, 5-year survival was lower in the PML group than in the LOB group: 41.3 vs 59.0% (P = 0.057). Similar results were found when analysing pT2-3 right-sided tumours: 27.3 vs 57.3% (P = 0.049). Multivariable analysis showed four independent prognostic factors: age (P = 0.001), pathological stage (P < 0.001), gender (P = 0.005) and the type of surgical resection (P = 0.029). PML (hazard ratio, HR = 1.63) and SEG (HR = 1.64) were detrimental in comparison with LOB. After adjusting for baseline differences between groups (propensity score), a trend towards a worse OS in PML group when compared with LOB group was observed (HR = 1.38, P = 0.150).

CONCLUSIONS

Both the lymphadenectomy yield and prognosis make PML more similar to SEG than lobectomy, especially for pT2-3 or G2-3 tumours.