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.

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.

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.

T category of non-small cell lung cancer invading the fissure to the adjacent lobe.

BACKGROUND: Dispute arises in the tumor category of non-small cell lung cancer invading the fissure to the adjacent lobe. The purpose of this study is to determine the long-term prognosis of non-small cell lung cancer with such an invasion and to propose an appropriate T category. METHODS: In total, 53 cases of non-small cell lung cancer invading the fissure to the adjacent lobe (fissure group) were identified in patients who underwent pulmonary resection from 1997 to 2014. Propensity score matching was applied to balance known confounders for prognosis between each paired group, resulting in 3 matched sets (fissure vs T2a, fissure vs T2b, and fissure vs T3). The overall survival of the fissure group was compared with the survival of patients with T2a, T2b, and T3 diseases, as classified in the eighth edition of TNM classification. RESULTS: The 5-year survivals of the T2a, T2b, T3, and fissure groups were 64.2% (95% confidence interval, 53.2-72.6), 54.6% (95% confidence interval, 44.7-65.8), 35.8% (95% confidence interval, 22.8-44.2), and 38.6% (95% confidence interval, 25.0-52.2), respectively. Specifically, the difference between the fissure group and T2a is statistically significant at P = .01; between the fissure group and T2b at P = .02; and between the fissure group and T3 at P = .93. Multivariate analyses indicate that the fissure group had a similar risk of dying as the T3 disease group (hazard ratio, 1.10; 95% confidence interval, 0.69-1.37) and was at a significantly higher risk compared with the T2a group (hazard ratio, 2.34; 95% confidence interval, 1.50-3.39) and T2b group (hazard ratio, 1.71; 95% confidence interval, 1.19-2.76). CONCLUSIONS: On the basis of our single-institution study, we propose that non-small cell lung cancer invading the fissure to the adjacent lobe should be further investigated and the impact on patients' prognoses validated as a T3 disease.

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

OBJECTIVES: To assess the results of surgical treatment of T-ALI (adjacent lobe invasion) tumours in patients with non-small-cell lung carcinoma. METHODS: Multicentric retrospective analysis of a prospectively maintained database of 13 065 patients, aged 32-89 years (mean 52.9, median 63 years), who underwent resection between January 2009 and September 2014. RESULTS: In the whole study group, T-ALI was observed in 324 patients (2.5%): 201 patients (62.0%) with a tumour invading the pleura in the inter-lobar fissure (T-ALI-A), and 123 patients (38.0%) with a tumour in the adjacent lobe but without pleural invasion in the fissure (T-ALI-D). With regard to N0 patients, the 3- and 5-year survival rates in the T2 group were significantly higher than that of the T-ALI group (76.1 and 68.4%, P = 0.002 vs 58.3 and 51.0%, P = 0.008, respectively). On the other hand, when the N1 group was analysed, the 5-year survival rates were 54.3 and 48%, respectively (P = 0.041). In the N2 group, the 5-year survival rates in the T2 and T-ALI groups were 40.2 and 35.0%, respectively (P = 0.241). The comparison of the T-ALI and T3 groups for stages N0, N1 and N2 revealed differences in 5-year survival rates as follows: 68.4 vs 62.9% (P = 0.048), 48.0 vs 37.6% (P = 0.08) and 35.0 vs 27.6% (P = 0.121), respectively. In the whole group, the difference in survival rate between T-ALI N0 and T2N0 was statistically significant (P = 0.008) and statistically significant for the T3N0 group (P = 0.048). The 3-year survival rate in the T-ALI N0 group was statistically lower following pneumonectomy than following lobectomy (56.4 vs 61.3%, P = 0.03). The best survival rate was observed following bilobectomy (75.6%). CONCLUSIONS: In our study, a tumour with ALI (T-ALI) represented a separate stage of cancer between T2 and T3. The survival rate in the T-ALI-A group was significantly poorer than that in the T-ALI-D group. Overall treatment results were similar for stage T3, suggesting that it may be necessary to divide this group into T3a and T3b. We would suggest that all tumours between 5 and 7 cm be classified as T3b, and any tumour smaller than 5 cm but with ALI be classified as T3a. Treatment of choice should include lobectomy or bilobectomy. Pneumonectomy should be performed only in a selected group of patients.