Results of surgical treatment and impact on T staging of non-small-cell lung cancer adjacent lobe invasion

Thoracoscopic segmentectomy for trans-fissure ground-glass opacity

OBJECTIVES

The trans-fissure ground-glass opacity (GGO) is a special category of lesions, with a diameter always exceeding 2 cm. It is located on a fused fissure, 'seizing' 2 neighbouring lobes simultaneously. The segmentectomy for the trans-fissure GGO is never reported.

METHODS

Between August 2016 and December 2022, patients operated with a trans-fissure GGO were included. The patients' backgrounds and surgical data were summarized. All procedures were performed with the help of preoperative three-dimensional computed tomography bronchography and angiography.

RESULTS

A total of 84 patients were included. The selection criteria included a consolidation tumour ratio <50% and a lesion size >2 and ≤3 cm. Thirty-six patients were operated with lobectomy + wedge (the traditional method group) and 48 patients were operated with anatomical segmentectomy + function-preserving sublobectomy (the new method group). The median operative time was 87 min in the traditional group and 98 min in the new method group, and the median blood loss was 60 ml in the traditional group and 70 ml in the new method group. The median duration of hospital stays was 4 days in the traditional group and 2 days in the new method group. In the traditional method group, there was 1 case of postoperative air leakage and 5 cases of haemoptysis. In the new method group, 2 cases of postoperative air leakage were identified. The median size of the tumour in the resected segment was 2.6 cm in the traditional group and 2.5 cm in the new method group. The median margin was 2.5 cm in the traditional group and 3.3 cm in the new method group.

CONCLUSIONS

The trans-fissure GGO could be safely resected en bloc by segmentectomy with a well-designed surgical procedure and appropriate preoperative planning.

Adjacent lobe invasion of T2 tumor in non-small cell lung cancer has T3 disease-like survival fissure invasion: T2 or T3?

Controversy still exists regarding the staging of non-small cell lung cancer (NSCLC) with adjacent lobe invasion (T-ALI) according to the TNM system in terms of T factor and the appropriate surgical resection method. We performed an analysis to compare the prognosis of T-ALI with T2 and T3 disease and to see the effect of our surgical method for these tumors. Two hundred consecutive patients between January 2012 and November 2020, with anatomical lobectomy for T2 or T3 tumor (Group-1) and non-anatomical lobectomy resection (lobectomy plus wedge resection [LWR]) (Group-2) for T-ALI (T2-ALI and T3-ALI) due to primary NSCLC, who did not have lymph node metastases were analyzed retrospectively. All surgeries were performed by two experienced surgeons who adopted the same surgical technique. Those who underwent additional segmentectomy and bilobectomy due to fissure invasion were excluded from the study. Overall survival rates of all patients were determined and factors affecting survival were evaluated by performing univariate and multivariate analyses. Of the patients with a mean age of 62.2 ± 7.8 years, 175 (87.5%) were male and 25 (12.5%) were female. There were 137 (68.5%) patients in Group 1 and 63 (31.5%) patients in Group 2. The mean tumor size in Group 1 (4.4 ± 1.4 cm) was significantly smaller than that in Group 2 (4.9 ± 1.4 cm) (p = 0.014). When T distribution within the groups was considered, the rate of pathological T3 in Group 1 (33.6%) was significantly lower than that in Group 2 (55.6%) (p = 0.005). While the 5-year overall survival rate was 70.1% in Group 1, it was 50.6% in Group 2 (p = 0.022). When tumors were grouped as T2, T2-ALI, T3, and T3-ALI according to T factor, the 5-year overall survival rates were 71.4% and 67.8% in T2 and T3 tumors, respectively, and 49.2% and 51.5% in T2-ALI and T3-ALI tumors, respectively. In the multivariate analysis of these four groups, the overall survival rates for T2-ALI and T3-ALI were significantly lower than those of T2 tumors (p = 0.046 and p = 0.025, respectively). In the analysis made between the T2 tumor group and the new T3 group (T2-ALI, T3, T3-ALI), which was formed by upgrading T2-ALI tumors to the T3 group, T2 tumors were found to have a significantly better survival rate (p = 0.019). The disease-free survival of pT2 patients and new T3 group patients was statistically significant, 63.7% and 45.7%, respectively (p = 0.050). Our results suggest that LWR for T-ALI can be performed with acceptable oncologic outcomes when compared to anatomical lobectomy. T2-ALI has a worse overall survival than T2 tumor and offers a similar prognosis to T3. Given this situation, it is more appropriate to classify T2-ALI as T3. Further studies based on larger series are needed to confirm these preliminary data.

Nomogram Predicting the Prognosis of Patients with Surgically Resected Stage IA Non-small Cell Lung Cancer

The American Joint Committee on Cancer (AJCC) 8th stage system was limited in accuracy for predicting prognosis of stage IA non-small cell lung cancer (NSCLC) patients. This study aimed to establish and validate two nomograms that predict overall survival (OS) and lung cancer-specific survival (LCSS) in surgically resected stage IA NSCLC patients. Postoperative patients with stage IA NSCLC in SEER database between 2004 and 2015 were examined. Survival and clinical information according to the inclusion and exclusion criteria were collected. All patients were randomly divided into the training cohort and validation cohort with a ratio of 7:3. Independent prognosis factors were evaluated using univariate and multivariate Cox regression analyses, and predictive nomogram was established based on these factors. Nomogram performance was measured using the C-index, calibration plots, and DCA. Patients were grouped by quartiles of nomogram scores and survival curves were plotted by Kaplan-Meier analysis. In total, 33,533 patients were included in the study. The nomogram contained 12 prognostic factors in OS and 10 prognostic factors in LCSS. In the validation set, the C-index was 0.652 for predicting OS and 0.651 for predicting LCSS. The calibration curves for the nomogram-predicted probability of OS and LCSS showed good agreement between the actual observation and nomogram prediction. DCA indicated that the clinical value of the nomograms were higher than AJCC 8th stage for predicting OS and LCSS. Nomogram scores related risk stratification revealed statistically significant difference which have better discrimination than AJCC 8th stage. The nomogram can accurately predict OS and LCSS in surgically resected patients with stage IA NSCLC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13193-022-01700-w.

Is adjacent lobe invasion an T category upgrade factor for resected non-small cell lung cancer ≤ 5 cm?

PURPOSE

Controversy exists with regard to the T category of non-small cell lung cancer (NSCLC) with adjacent lobe invasion (ALI), and dispute arises on assigning this subset into T2 or T3 category. We evaluated the effect of ALI on the survival of resected NSCLC ≤ 5 cm, with purpose of determining the most appropriate T category for this population.

METHODS

The entire cohort was divided into three subgroups (ALI group, T2 group and T3 group). Kaplan-Meier with log-rank method was carried out to compare overall survival (OS) differences. Propensity score matching (PSM) was performed to minimize bias.

RESULTS

A total of 12,564 eligible NSCLC cases (ALI group: 114 cases; T2 group: 10,046 cases; T3 group: 2404 cases) were included in this study. The incidence of ALI was about 0.9%. Before PSM, survival analyses demonstrated that no significant OS differences were observed between ALI group and T2 group, and between ALI group and T3 group, neither in the entire cohort analysis nor in the subgroup analysis. After PSM, there were 102 pairs and 98 pairs in the ALI and T2 matching group and ALI and T3 matching group, respectively. In the matched cohorts, survival curves showed that the OS of ALI group was comparable to that of T2 group (P = 0.950), but superior to that of T3 group (P = 0.012).

CONCLUSIONS

The current study proposed that NSCLC with ALI ≤ 5 cm should be still categorized as T2 category, which could improve staging accuracy.

Computed tomography-guided microwave ablation for the treatment of non-small cell lung cancer patients with and without adjacent lobe invasion: A comparative study

BACKGROUND

The aim of the study was to explore the outcomes of computed tomography-guided microwave ablation (MWA) in non-small cell lung cancer (NSCLC) patients with adjacent lobe invasion (ALI), and to compare the outcomes of ALI-NSCLC and non-ALI NSCLC patients after MWA.

METHODS

A total of 319 NSCLC patients and 366 tumors treated with MWA were included in the study, comprising 34 ALI-NSCLC patients and 285 non-ALI NSCLC patients. Complications, local recurrence rates, progression-free survival (PFS), and overall survival (OS) were compared. Logistic regression analyses were used to investigate the correlation between ALI and the occurrence of pneumothorax after MWA.

RESULTS

The mean tumor diameter of ablated tumors was 3.6 ± 2.2 cm. There were 95 (29.8%) NSCLC patients in which pneumothorax occurred after MWA, and all patients recovered. Of these, the ALI group had a significantly higher incidence rate of pneumothorax than the non-ALI group (52.9% vs. 27.0%, p = 0.002). The median PFS and OS for the ALI group were 12.0 ± 10.2 and 15.5 ± 9.5 months, respectively, and that of the non-ALI group were 13.0 ± 10.6 and 17.0 ± 11.1 months, respectively, and no significant difference was found in PFS (p = 0.329) nor OS (p = 0.394) between the two groups. Local recurrence rates for ALI and non-ALI groups were 29.4% and 20.7%, respectively, and no significant difference was found (p = 0.244). Logistic regression analyses revealed that ALI can increase the risk of pneumothorax (hazard ratio [HR], 2.867; p = 0.012).

CONCLUSIONS

MWA is an effective and safe approach for ALI-NSCLC treatment. Although ALI can increase the risk of pneumothorax, ALI-NSCLC patients reveal a comparable outcome to non-ALI NSCLC patients after MWA.

Surgical treatment of lung cancer with adjacent lobe invasion in relation to fissure integrity

BACKGROUND

Tumor with adjacent lobe invasion (T-ALI) is an uncommon condition. Controversy still exists regarding the optimal resection of adjacent lobe invasion, and the prognostic value in relation to fissure integrity at the tumor invasion point. The aims of this paper were to evaluate the prognosis of T-ALI with regard to fissure integrity, and type of resection.

METHODS

This was a retrospective multicenter study which included all consecutive patients with T-ALI undergoing surgical treatment. Based on radiological, intraoperative and histological findings, T-ALI patients were differentiated into two groups based on whether the fissure was complete (T-ALI-A group) or incomplete (T-ALI-D Group) at the level of tumor invasion point. Clinico-pathological features and survival of two study groups were analyzed and compared.

RESULTS

Study population included 135 patients, of these 98 (72%) were included into T-ALI-A group, and 37 (38%) into T-ALI-D Group. T-ALI-D patients had better overall survival than T-ALI-A patients (63.9 ± 7.0 vs. 48.9 ± 3.9; respectively, P = 0.01) who presented with a higher incidence of lymph node involvement (35% vs. 4%; P = 0.004), and recurrence rate (43% vs. 16%; P = 0.01). At multivariable analysis, T-ALI-D (P = 0.01), pN0 stage (P = 0.0002), and pT≤5 cm (P = 0.0001) were favorable survival prognostic factors.

CONCLUSIONS

T-ALI-D presented a better prognosis than T-ALI-A while extent of resection had no effect on survival. Thus, in patients with small T-ALI-D and without lymph node involvement, sublobar resection of adjacent lobe rather than lobectomy could be indicated.

KEY POINTS

The extent of resection of adjacent lobe had no effect on survival while T-ALI-D, pN0 stage, and pT≤5 cm were significant prognostic factors. In patients with small T-ALI-D and without lymph node involvement, sublobar resection of adjacent lobe could be indicated as an alternative to lobectomy.