Segmental volumetric analysis with a ventilated or perfused area: identifying the intersegmental plane.

OBJECTIVES: Two methods are available to identify the intersegmental plane during segmentectomy: the inflation-deflation method, based on the ventilation area, and injection of indocyanine green, based on the pulmonary arterial distribution. However, whether the intersegmental plane created by these 2 methods matches remains unknown. Our goal was to identify the demarcation lines based on bronchial and arterial territories using 3-dimensional computed tomography-based volumetry. METHODS: We collected data from patients who underwent thoracoscopic segmentectomy in our hospital between April 2012 and May 2021. Three-dimensional images were reconstructed from the preoperative contrast-enhanced computed tomography data using the SYNAPSE VINCENT software program. The volume of the affected area and the distance of the tumour from the intersegmental plane were calculated based on each affected artery and bronchus. Each calculated volume was compared to each affected segment using a paired t-test. RESULTS: Of 195 patients, 114 underwent upper lobe segmentectomy, and 81 underwent lower lobe segmentectomy. In upper lobe segmentectomy, the affected arterial segmental volume was smaller than the bronchial volume (505.0 ml vs 539.4 ml, P < 0.001). In lower lobe segmentectomy, there was no significant difference between arterial and bronchial volumes (234.6 ml vs 236.9 ml, P = 0.607). The volume of the affected arterial segmental lung and the distance of the tumour from the intersegmental plane were significantly smaller than the bronchial volume in upper lobe segmentectomies. CONCLUSIONS: As per the results, the affected segmental volume delineated by the indocyanine green method would be underestimated in upper lobe segmentectomy.

Resected stage I anaplastic lymphoma kinase-positive lung adenocarcinoma has a negative impact on recurrence-free survival.

BACKGROUND: The clinical and prognostic implications of anaplastic lymphoma kinase (ALK) status in resected lung cancers remain unclear. In this study we analyzed the prognostic and predictive significance of ALK-positive among patients with completely resected lung adenocarcinoma. METHODS: We retrospectively reviewed 197 patients with lung adenocarcinoma who underwent complete surgical resection and had been tested for their ALK status. We investigated the impact of an ALK-positive status on the recurrence-free survival (RFS) and overall survival (OS) and examined the predictive factors for an ALK-positive status. RESULTS: ALK positivity was noted in 36 (18%) out of 197 patients, and when limited to stage I patients, in 24 (19%) out of 124. In the pathological-stage I population, while the OS exhibited no significant difference between ALK-positive and ALK-negative patients (5-year OS rate, 81.2% vs. 89.8%, p = 0.226), the RFS of ALK-positive patients was significantly worse than that of ALK-negative patients (5-year RFS rate, 55.9% vs. 78.8%, p = 0.018). A multivariate analysis showed that ALK-positive status (hazard ratio [HR] 3.431, p = 0.009) was an independent prognostic factor for the RFS. Regarding the relationship between clinicopathological factors and an ALK-positive status, a high-grade histological subtype, including solid and micropapillary subtypes (odds ratio [OR] 5.464, p < 0.001), and never-smokers (OR 4.292, p = 0.018) were associated with ALK-positive. CONCLUSION: A high-grade histological subtype and never-smokers were associated with ALK positivity, and the RFS of ALK-positive patients was worse than that of ALK-negative patients among patients with completely resected stage I lung adenocarcinoma.

The difference in postoperative pulmonary functional change between upper and lower thoracoscopic lobectomy.

OBJECTIVES: Through 3-dimensional lung volumetric and morphological analyses, we aimed to evaluate the difference in postoperative functional changes between upper and lower thoracoscopic lobectomy. METHODS: A total of 145 lung cancer patients who underwent thoracoscopic upper lobectomy (UL) were matched with 145 patients with lung cancer who underwent thoracoscopic lower lobectomy (LL) between April 2012 and December 2018, based on their sex, age, smoking history, operation side, and pulmonary function. Spirometry and computed tomography were performed before and 6 months after the operation. In addition, the postoperative pulmonary function, volume and morphological changes between the 2 groups were compared. RESULTS: The rate of postoperative decreased and the ratio of actual to predicted postoperative forced expiratory volume in 1 s were significantly higher after LL than after UL (P < 0.001 for both). The tendency above was similar irrespective of the resected side. The postoperative actual volumes of the ipsilateral residual lobe and contralateral lung were larger than the preoperatively measured volumes in each side lobectomy. Moreover, the increased change was particularly remarkable in the middle lobe after right LL. The change in the D-value, representing the structural complexity of the lung, was better maintained in the left lung after LL than after UL (P = 0.042). CONCLUSIONS: Pulmonary function after thoracoscopic LL was superior to that after UL because the upward displacement and the pulmonary reserves of the remaining lobe appeared more robust after LL.

Cluster analysis of emphysema for predicting pulmonary complications after thoracoscopic lobectomy.

OBJECTIVES: Despite significant advances in surgical techniques, including thoracoscopic approaches and perioperative care, the morbidity rate remains high after lung resection. This study focused on a low attenuation cluster analysis, which represented the size distribution of pulmonary emphysema and assessed its utility for predicting postoperative pulmonary complications after thoracoscopic lobectomy. METHODS: From April 2013 to September 2018, lung cancer patients who received spirometry and computed tomography (CT) before surgery and underwent thoracoscopic lobectomy were included. The cumulative size distribution of the low attenuation area (LAA, defined as ≤-950 Hounsfield unit on CT) clusters followed a power-law characterized by an exponent D-value, a measure of the complexity of the alveolar structure. D-value and LAA% (LAA/total lung volume) were calculated using preoperative 3-dimensional CT software. The relationship between pulmonary complications and patient characteristics, including D-value and LAA%, was investigated. RESULTS: Among 471 patients, there were 61 respiratory complication cases (12.9%). Receiver operation characteristic curve analysis revealed that the best predictive cut-off value of D-value and LAA% for pulmonary complications was 2.27 and 16.5, respectively, with an area under the curve of 0.72 and 0.58, respectively. D-value was significantly correlated with % forced expiratory volume in 1 s. Per univariate analysis, gender, smoking history, forced expiratory volume in 1 s/forced vital capacity, LAA% and D-value were risk factors for predicting postoperative pulmonary complications. In the multivariate analysis, D-value remained a significant predictive factor. CONCLUSION: Preoperative assessment of emphysema cluster analysis may represent the vulnerability of the operated lung and could be the novel predictor for pulmonary complications after thoracoscopic lobectomy.

Pleural invasion, epidermal growth factor receptor mutation and carcinoembryonic antigen level affect pleural lavage cytology-positive status in non-small-cell lung cancer.

OBJECTIVES: Pleural invasion (pl) is strongly associated with the pleural lavage cytology (PLC) status. We analysed tumours with pl and evaluated the relationship between the PLC status and pl. METHODS: We retrospectively reviewed 428 surgically treated patients who had been diagnosed with non-small-cell lung cancer with pl and had their PLC status examined between 2000 and 2016. We investigated the influence of a PLC-positive status on the prognosis and searched for the factors predictive of a PLC-positive status. RESULTS: Seventy-eight (18%) patients were PLC positive. The recurrence-free survival of PLC-positive patients was significantly worse than that of PLC-negative patients in pl1 and pl2, but not in pl3 (5-year recurrence-free survival rate, PLC positive versus PLC negative: pl1, 22.0% vs 60.0%, P = 0.002; pl2, 30.4% vs 59.7%, P = 0.015; pl3, 50.0% vs 59.6%, P = 0.427). A multivariable analysis showed that the degree of pl (pl2-3 versus pl1) [odds ratio (OR) 5.34, P < 0.001] was an independent predictive factor for PLC positivity. Epidermal growth factor receptor (EGFR) mutation positivity (OR 5.48, P = 0.042) and carcinoembryonic antigen (CEA) ≥5 ng/ml (OR 3.78, P = 0.042) were associated with a PLC-positive status in patients with pl2-3. We found that the PLC-positive rate in patients with pl2-3 was 35.6%; however, if the tumour was EGFR mutation positive and had CEA ≥5 ng/ml, the PLC-positive rate increased to 77%. CONCLUSIONS: If a tumour was suspected of being pl2-3 and had EGFR mutation positivity and CEA ≥5 ng/ml, the PLC-positive rate was extremely high. CLINICAL TRIAL REGISTRATION NUMBER: Hyogo Cancer Center, G-138.