Risk Factors for Recurrence of Stage I Epidermal Growth Factor Receptor Mutated Lung Adenocarcinoma

BACKGROUND

We aimed to clarify the risk factors for postoperative recurrence in patients with epidermal growth factor receptor (EGFR)-mutated stage I lung adenocarcinoma, using EGFR wild-type adenocarcinoma as a comparator, to select optimal candidates for adjuvant therapy with EGFR tyrosine kinase inhibitor (TKI).

METHODS

Data of patients with pathologic stage I EGFR-mutated (n = 713) and wild-type (n = 673) adenocarcinoma who did not receive adjuvant therapy were retrospectively analyzed. The cumulative incidence of recurrence (CIR) was estimated using Gray's method, and multivariable Fine-Gray competing risk models identified independent risk factors associated with recurrence.

RESULTS

The CIR did not differ significantly between patients with EGFR-mutated and wild-type adenocarcinoma (P = .32). Multivariable analysis revealed that greater size (cm) of invasive tumor (hazard ratio 1.539; 95% CI, 1.077-2.201), lymphovascular invasion (hazard ratio 5.180; 95% CI, 2.208-12.15), pleural invasion (hazard ratio 3.388; 95% CI, 1.524-7.533), and high-grade histologic subtype (hazard ratio 4.295; 95% CI, 1.539-11.99) were independent risk factors for recurrence in patients with EGFR-mutated adenocarcinoma. The 5-year CIR was significantly higher among patients with these factors (tumor size greater than 2 cm, 15.9%; lymphovascular invasion, 26.9%; pleural invasion, 39.3%; and high-grade subtype, 44.4%) than among patients without them (4.4%, 2.2%, 3.9%, and 5%, respectively; P < .001). For patients with EGFR wild-type adenocarcinoma, independent risk factors for recurrence were invasive tumor size, lymphovascular invasion, and pleural invasion, but not histologic subtypes.

CONCLUSIONS

Even for patients with EGFR-mutated stage I lung adenocarcinoma, recurrence risk is stratified. Adjuvant therapy may be considered if they have high-risk factors for recurrence.

Omitting Lymph Node Dissection for Small Ground-Glass Opacity-Dominant Tumors

BACKGROUND

The purpose of this study was to determine the optimal extent of lymph node dissection required in patients with small (≤3 cm) radiologically ground-glass opacity-dominant, peripheral, non-small cell lung cancer tumors.

METHODS

The study analyzed the clinicopathologic findings and surgical outcomes of 988 patients with radiologic, ground-glass opacity-dominant non-small cell lung cancer without lymph node involvement who underwent complete resection of the primary tumor between 2010 and 2020. Patients were followed up for 54.5 months (median). Kaplan-Meier curves and the log-rank test were used in statistical analyses of the prognosis.

RESULTS

Median age, whole tumor size, solid tumor size, and maximum standardized uptake values were 68 years, 1.7 cm, 0.4 cm, and 0.9, respectively. Sixty percent of the cohort was female (n = 590). Wedge resection, segmentectomy, and lobectomy were performed in 206, 372, and 410 patients, respectively. A total of 982 of 988 (99%) tumors were adenocarcinomas. One patient had hilar lymph node involvement; however, no mediastinal lymph node metastasis or hilar or mediastinal lymph node recurrence was detected. The 5-year overall survival rate was 96.5% (95% CI, 94.8%-97.7%). Excellent survival outcomes were achieved regardless of procedure (wedge resection, 94.7% [95% CI, 89.1%-97.5%]; segmentectomy, 96.9% [95% CI, 93.7%-98.5%]; and lobectomy, 97.1% [95% CI, 94.4%-98.5%]).

CONCLUSIONS

Omitting lymph node dissection may be acceptable with curative intent for small tumors with radiologic ground-glass opacity dominance. Appropriate surgical procedures such as wedge resection, segmentectomy, or lobectomy can provide satisfactory outcomes in patients with indolent tumors if surgical margins are secured.

Tumor distance from the mediastinum predicts N2 upstaging in clinical stage I lower-lobe non-small cell lung cancer

OBJECTIVE

Pulmonary lymphatic drainage of the lower lobe into the mediastinal lymph nodes includes not only the pathway via the hilar lymph nodes but also the pathway directly into the mediastinum via the pulmonary ligament. This study aimed to determine the association between the distance from the mediastinum to the tumor and the frequency of occult mediastinal nodal metastasis (OMNM) in patients with clinical stage I lower-lobe non-small cell lung cancer (NSCLC).

METHODS

Between April 2007 and March 2022, data of patients who underwent anatomical pulmonary resection and mediastinal lymph node dissection for clinical stage I radiological pure-solid lower-lobe NSCLC were retrospectively reviewed. In computed tomography axial sections, the ratio of the distance from the inner edge of the lung to the inner margin of the tumor within the lung width of the affected lung was defined as the inner margin ratio. Patients were divided into 2 groups based on whether the inner margin ratio was ≤0.50 (inner-type) or >0.50 (outer-type), and the association between inner margin ratio status and clinicopathological findings was assessed.

RESULTS

In total, 200 patients were enrolled in the study. OMNM frequency was 8.5%. More inner-type than outer-type patients had OMNM (13.2% vs 3.2%; P = .012) and skip N2 metastasis (7.5% vs 1.1%; P = .038). Multivariable analysis revealed that the inner margin ratio was the only independent preoperative predictor of OMNM (odds ratio, 4.72; 95% CI, 1.31-17.07; P = .018).

CONCLUSIONS

Tumor distance from the mediastinum was the most important preoperative predictor of OMNM in patients with lower-lobe NSCLC.

Clinical Significance of Preserving Pulmonary Function After Lung Resection in Early-Stage Non-Small-Cell Lung Cancer

INTRODUCTION

To determine the association between changes in pulmonary function before and after surgery, and the subsequent prognosis, of patients with early-stage non-small-cell lung cancer (NSCLC).

METHODS

A total of 485 patients who underwent lobectomy or segmentectomy for NSCLC with whole tumor size ≤2 cm and clinical stage IA at 2 institutions were retrospectively reviewed. The relationship between the postoperative reduction rate in vital capacity (VC), forced vital capacity (FVC), and forced expiratory volume in 1 second (FEV1) and overall survival (OS) was investigated. OS determined the cut-off value of the reduction rate, according to the reduction rate of every 10% in pulmonary function.

RESULTS

Multivariable Cox regression analysis showed that a reduction rate in VC at 12 months postoperatively was an independent prognostic factor for OS (hazard ratio, 1.05; 95% confidence interval [CI], 1.02-1.07; P < .001) but those in FVC and FEV1 were not. OS was classified into good and poor with 20% reduction rate in VC. OS and recurrence-free survival (RFS) in a higher than 20% reduction rate in VC were worse than those in ≤20% reduction rate in VC (5 year-OS; 82.0% vs. 93.4%; P = .0004. Five year-RFS; 80.3% vs. 89.8%; P = .0018, respectively). Multivariable logistic analysis showed that lobectomy was a risk factor for the higher than 20% reduction rate in VC (odds ratio, 1.61; 95% CI, 1.01-2.56; P = .045).

CONCLUSIONS

Postoperative decrease in VC was significantly associated with the prognosis. Preserving pulmonary function is important for survival of patients with early-stage NSCLC.

Sublobar Resection in Early Non-Small Cell Lung Cancer With Epidermal Growth Factor Receptor Mutant

BACKGROUND

Lobectomy is a standard surgical procedure for peripherally located early-stage non-small cell lung cancers (NSCLCs) measuring 2 to 4 cm. However, it is unclear whether sublobar resections, such as wedge resection and segmentectomy, are effective in treating tumors with driver mutations in the epidermal growth factor receptor (EGFR).

METHODS

We analyzed the clinicopathologic findings and surgical outcomes of 1395 patients with radiologically solid-dominant NSCLC measuring 2 to 4 cm, without clinical lymph node involvement, who underwent complete resection between 2010 and 2020. The patients, who underwent sublobar resections (n = 231) or lobectomy (n = 1164), were categorized by their EGFR mutation status and the surgical procedures performed. The follow-up was conducted for a median of 45.3 months.

RESULTS

The 5-year overall survival (OS) rates after sublobar resections (n = 39) were comparable to those after lobectomy (n = 359) in patients with EGFR mutation-positive tumors (80.5% [95% CI, 51.3%-93.2%] vs 88.8% [95% CI, 84.1%-92.1%], respectively; P = .16). Multivariable Cox regression analysis of OS revealed that the surgical procedure was an independent prognostic predictor in the entire cohort (hazard ratio, 0.6; 95% CI, 0.4-1.0; P = .028), but it was not an independent prognostic predictor in patients with EGFR-mutated tumors (hazard ratio, 0.6; 95% CI, 0.2-1.7; P = .32).

CONCLUSIONS

Sublobar resection with a secure surgical margin could be a viable option for appropriately selected patients with peripheral early-stage NSCLC tumors measuring 2 to 4 cm and harboring EGFR mutations, because it provides comparable OS to that of lobectomy.

Effectiveness of pleurodesis for postoperative air leaks after lung resection

BACKGROUND

Pleurodesis is often performed for air leaks; however, the ideal materials and timing of the procedure remain controversial. We investigated the efficacy of pleurodesis using different materials and timing.

METHODS

We retrospectively reviewed 913 consecutive patients who underwent segmentectomy or lobectomy for non-small cell lung cancer between 2014 and 2021. Pleurodesis efficacy was assessed on the day of chest tube removal.

RESULTS

Eighty-six patients (9%) underwent pleurodesis for postoperative air leaks. Pleurodesis was performed on a median of postoperative day (POD) 5. Talc was the most frequently used material (n = 52, 60%), followed by autologous blood patches (n = 20, 23%), OK-432 (n = 12, 14%), and others (n = 2, 2%). No difference existed in the number of days from initial pleurodesis to chest tube removal among the three groups (talc, 3 days; autologous blood patch, 3 days; OK-432, 2 days; P = 0.55). No difference in patient background, except for sex, was observed between patients who underwent pleurodesis within 4 PODs and those who underwent pleurodesis on POD 5 or later. Drainage time was significantly shorter in patients who underwent pleurodesis within 4 PODs (median, 7 vs. 9 days; P = 0.004).

CONCLUSIONS

The efficacies of autologous blood patch, talc, and OK-432 would be considered comparable and early postoperative pleurodesis could shorten drainage time. Prospective studies are required.

Successful conservative treatment for massive tracheal necrosis after lung segmentectomy

BACKGROUND

Tracheal necrosis, which is rare because the trachea has rich in blood supply, can be a serious condition. Herein, we report the case of extensive tracheal necrosis that developed after right apical segmentectomy for a metastatic lung tumor of esophageal cancer.

CASE PRESENTATION

A 74-year-old man who had undergone thoracoscopic subtotal esophagectomy and gastric tube reconstruction via the posterior sternal route for esophageal adenocarcinoma 2 years previously was referred to our department with an enlarging nodal lesion in the right upper lung lobe. Computed tomography revealed a 30-mm tumor in the right apical segment with no lymph node enhancement, suggesting primary lung cancer or a metastatic lung tumor. The patient underwent right apical segmentectomy. The upper lobe was adherent to the chest wall and mediastinal fat from the apex of the lung to the dorsal side, with particularly strong adhesion at the esophagectomy site. After dissecting the adhesions, right apical segmentectomy was performed via complete video-assisted thoracic surgery. The patient was discharged on the 9th day after surgery without any complications. Pathologic findings revealed a metastatic lung tumor originating from the patient's esophageal cancer. On the 26th day after surgery, the patient returned with dyspnea and increased sputum. Computed tomography images revealed that the posterior wall of the trachea was missing an area of 16 × 42 mm and was connected to the dead space after the right apical segmentectomy, with no effusion. We diagnosed extensive tracheal necrosis. Considering that the patient's status was very well despite the extensive tracheal necrosis, we chose conservative treatment. After receiving 12 days of intravenous antibiotic treatment, his symptoms improved, and he was discharged on day 26 after admission.

CONCLUSIONS

Right upper lung lobe resection after esophagectomy has a risk of tracheal necrosis. Conservative treatment is one approach to manage massive tracheal necrosis in patients with stable respiratory conditions.

Segmentectomy for cancer control in radiologically pure-solid clinical stage IA3 lung cancer

OBJECTIVES

This study aimed to compare cancer control after segmentectomy and lobectomy in patients with radiologically pure-solid clinical stage IA3 non-small-cell lung cancer (NSCLC).

METHODS

Patients with radiologically pure-solid clinical stage IA3 NSCLC who underwent lobectomy or segmentectomy at 3 institutions between 2010 and 2019 were identified. We estimated propensity scores to adjust for confounding variables regarding tumour malignancy, including age, sex, smoking history, tumour size, maximum standardized uptake value on 18F-fluorodeoxyglucose positron emission tomography, lymph node dissection, histological type and lymphatic, vascular and pleural invasion. Cumulative incidence of recurrence (CIR) was evaluated as a primary end point.

RESULTS

Among 412 patients, postoperative recurrence occurred in 7 of 44 patients (15.9%) undergoing segmentectomy, and 71 of 368 patients (19.3%) undergoing lobectomy. CIR was comparable between patients undergoing segmentectomy (5-year rate, 21.9%) and those undergoing lobectomy (5-year rate, 20.8%; P = 0.88). Locoregional recurrence did not differ between patients undergoing segmentectomy (6.8%) and those undergoing lobectomy (9.0%). In multivariable analysis, segmentectomy (versus lobectomy) was not identified as an independent prognostic factor for CIR (hazard ratio, 1.045; 95% confidence interval, 0.475-2.298; P = 0.91). In propensity score matching of 40 pairs, CIR was not significantly different between patients undergoing segmentectomy (5-year rate, 20.7%) and those undergoing lobectomy (5-year rate, 18.4%; P = 0.81).

CONCLUSIONS

Cancer control may be comparable between segmentectomy and lobectomy in patients with radiologically pure-solid clinical stage IA3 NSCLC. Further studies are warranted to clarify the survival benefits of segmentectomy in these patients.

Risk factors for long-term decline in post-operative pulmonary function after lung resection

OBJECTIVES

The study aimed to examine the risk factors for long-term decline in pulmonary function after anatomical resection for lung cancer and the effects of the decrease on survival.

METHODS

We retrospectively examined 489 patients who underwent anatomical resection for lung cancer between 2010 and 2020. Pulmonary function tests were performed preoperatively and at 1, 3, 6 and 12 months after surgery. The lower interquartile medians of the reduction rates of forced expiratory volume in 1 s and vital capacity at 12 months after surgery were taken as the cut-off values of risk factors for the decrease in post-operative pulmonary function.

RESULTS

Forced expiratory volume in 1 s and vital capacity decreased the most in the first month after surgery and then gradually recovered. Vital capacity continued to increase even after 6 months post-surgery, whereas forced expiratory volume in 1 s stabilized. Multivariable logistic analysis showed that the number of resected segments (odds ratio, 2.09; 95% confidence interval, 1.12-3.89; P = 0.019) was a risk factor for the decrease in forced expiratory volume in 1 s at 12 months, and the numbers of resected segments (odds ratio, 1.36; 95% confidence interval, 1.13-1.63; P < 0.001) and post-operative complications (odds ratio, 2.32; 95% confidence interval, 1.01-5.35; P = 0.047) were independent risk factors for decrease in vital capacity. Multivariate cox regression analysis showed that the decrease in vital capacity at 12 months was significantly associated with overall survival (hazard ratio, 2.02; 95% confidence interval, 1.24-3.67; P = 0.004).

CONCLUSIONS

Long-term decrease in vital capacity, which was influenced by the number of resected segments and post-operative complications, adversely affected survival.

Segmentectomy preserves better immune-nutritional status than lobectomy in patients with early-stage lung cancer

OBJECTIVES

This study aimed to compare the postoperative immune-nutritional status of patients undergoing segmentectomy and lobectomy for early-stage non-small-cell lung cancer.

METHODS

Patients with clinical stage 0-IA non-small-cell lung cancer who underwent lobectomy or segmentectomy were retrospectively analysed. Postoperative immune-nutritional indices (prognostic nutritional index, serum albumin levels and total lymphocyte count) at 1 month, 6 months, 1 year, 2 years and 3 years after surgery were compared using mixed effects linear models and mixed effects logistic regression models.

RESULTS

There were 164 and 210 patients in the lobectomy and segmentectomy groups, respectively. Postoperative prognostic nutritional index and albumin levels were significantly higher in the segmentectomy group than those in the lobectomy group (P < 0.001 and P < 0.001, respectively), despite the nonsignificant difference in the total lymphocyte count (P = 0.563). In 126 propensity score-matched pairs adjusted for confounding variables affecting postoperative nutritional status, postoperative prognostic nutritional index and albumin levels were significantly higher in the segmentectomy group than in the lobectomy group (P = 0.009 and P = 0.007, respectively). At each time point after surgery, these indices were higher in the segmentectomy group than in the lobectomy group at 1 month, 2 years and 3 years postoperatively. There were significantly more patients with lower immune-nutritional indices (prognostic nutritional index <45, albumin <4.0 g/dl) in the lobectomy group than in the segmentectomy group at 3 years postoperatively (P = 0.026 and P = 0.029, respectively), despite nonsignificant statistical differences throughout the study period (P = 0.219 and P = 0.113, respectively).

CONCLUSIONS

Patients who underwent segmentectomy showed better postoperative immune-nutritional status than those who underwent lobectomy.

Wedge resection is an acceptable treatment option for radiologically low-grade lung cancer with solid predominance

OBJECTIVES

This study aimed to determine the clinical characteristics for predicting low-grade cancer in radiologically solid predominant non-small-cell lung cancer (NSCLC) and compare the survival outcomes of wedge resection with those of anatomical resection for patients with and without these characteristics.

METHODS

Consecutive patients with clinical stages IA1-IA2 NSCLC showing radiologically solid predominance ≤2 cm at 3 institutions were retrospectively evaluated. Low-grade cancer was defined as the absence of nodal involvement and blood vessel, lymphatic and pleural invasion. The predictive criteria for low-grade cancer were established by multivariable analysis. The prognosis of wedge resection was compared with that of anatomical resection for patients who met the criteria, using the propensity score-matched analysis.

RESULTS

Among 669 patients, multivariable analysis showed that ground-glass opacity (GGO) (P < 0.001) on thin-section computed tomography and an increased maximum standardized uptake value on 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography (P < 0.001) were independent predictors of low-grade cancer. The predictive criteria were defined as GGO presence and maximum standardized uptake value ≤1.1 (specificity: 97.8%, sensitivity: 21.4%). In the propensity score-matched pairs (n = 189), overall survival (P = 0.41) and relapse-free survival (P = 0.18) were not significantly different between patients who underwent wedge resection and anatomical resection among those who fulfilled the criteria.

CONCLUSIONS

The radiologic criteria for GGO and a low maximum standardized uptake value could predict low-grade cancer, even in solid-dominant NSCLC sized ≤2 cm. Wedge resection could be an acceptable surgical option for patients with radiologically predicted indolent NSCLC showing a solid-dominant appearance.

Impact of the amount of preoperative erector spinae muscle in stage I non-small-cell lung cancer

OBJECTIVES

Erector spinae muscle (ESM) is an antigravity muscle group that can be evaluated as an index of muscle loss on chest computed tomography. The amount of ESM has been reported to be related to the prognosis of several respiratory diseases. However, few studies clarify the impact on postoperative non-small-cell lung cancer (NSCLC). We investigated the relationship between ESM and postoperative prognosis in patients with early-stage NSCLC.

METHODS

We reviewed the medical records of 534 patients with stage I NSCLC who underwent lobectomy or segmentectomy. The ESM was identified by preoperative computed tomography, and the amount was normalized according to height and sex. Overall survival, lung cancer-related deaths and non-lung cancer-related deaths (NLCRD) were analysed using log-rank and Gray's tests. Multivariable analyses were conducted to identify factors that influenced overall survival (OS) and NLCRD.

RESULTS

The amount of ESM normalized according to height and sex was significantly associated with age and body mass index. When the amount was low, OS (5-year OS, 79.6 vs 89.5%; P< 0.001) and NLCRD (5-year cumulative mortality rate, 14.7 vs 6.8%; P< 0.001) were significantly worse, although no difference was found in lung cancer-related deaths.

CONCLUSIONS

The amount of preoperative ESM was strongly related to non-lung cancer-related death and was a significant prognostic factor for stage I NSCLC. Patients with a low amount of the muscle should be treated based on proper risk assessment.

Histopathology and Cytology of Pulmonary Myoepithelial Neoplasms: 2 Cases

Myoepithelial neoplasms (MNs) of the lung are extremely rare tumors. Approximately 40 cases of pulmonary MNs have been reported to date. Herein, we report extremely rare cases of different types of pulmonary MN, including cytological features. Case 1 is an 18-year-old female, and case 2 is a 73-year-old female patient. They presented to our hospital with nodules of the lung. Histological examination revealed tumor cells with round to oval nuclei and acidophilic cytoplasm that formed nests or fascicles with mild hyalinized stroma in case 1 and tumors containing the bi-phasic components of a nest-like and fascicle pattern with pleomorphism in case 2. Immunohistochemically, these tumors were positive for cytokeratin (CK) AE1/AE3, CK5/6, vimentin, calponin, and EMA, and focal positive for S-100a protein and alpha smooth muscle actin. The pathological diagnoses in cases 1 and 2 were myoepithelioma and myoepithelial carcinoma, respectively. In conclusion, we encountered two cases of extremely rare MNs that occurred in the lung. This disease can be diagnosed by collecting appropriate cytological and histological findings and should be listed as a differential diagnosis.

Classification based on skeletal muscle mass and the severity of lung emphysema impacts on clinical outcomes after anatomical resection for lung cancer

OBJECTIVES

Both sarcopenia and lung emphysema are prognostic factors in lung cancer and can be easily assessed using the psoas muscle index and Goddard score, respectively. We investigated the clinical significance of the classification based on psoas muscle index and Goddard score in non-small cell lung cancer.

METHODS

A total of 303 consecutive patients who underwent anatomical resection for non-small cell lung cancer were retrospectively analyzed. The psoas muscle at the level of the third lumbar vertebrae and Goddard score were measured on preoperative computed tomography. The psoas muscle was adjusted by height as the psoas muscle index (cm2/m2). We divided patients into three groups: low-, middle- and high-risk, using cut-off values of psoas muscle index < 6.36 cm2/m2 for males and 3.92 cm2/m2 for females and Goddard score higher than 7. The predictors of postoperative complications and prognosis were examined.

RESULTS

High-, middle- and low-risk were present in 30 (10%), 164 (54%) and 109 (36%) patients, respectively. High risk was significantly associated with male sex, low pulmonary function, more comorbidities and increased postoperative complications. High-risk patients showed poorer overall survival than middle- and low-risk patients (P < 0.001). Multivariable analysis revealed that high risk was an independent risk factor for postoperative complications and unfavorable prognostic factors (P = 0.011, P = 0.014, respectively).

CONCLUSIONS

Classification based on psoas muscle index and Goddard score is significantly associated with short- and long-term outcomes in patients with lung cancer. This method can be easily assessed for patients and may help select patients for nutritional support and rehabilitation before surgery.

Rb and p53-Deficient Myxofibrosarcoma and Undifferentiated Pleomorphic Sarcoma Require Skp2 for Survival

Myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) are highly genetically complex soft tissue sarcomas. Up to 50% of patients develop distant metastases, but current systemic therapies have limited efficacy. MFS and UPS have recently been shown to commonly harbor copy number alterations or mutations in the tumor suppressor genes RB1 and TP53. As these alterations have been shown to engender dependence on the oncogenic protein Skp2 for survival of transformed cells in mouse models, we sought to examine its function and potential as a therapeutic target in MFS/UPS. Comparative genomic hybridization and next-generation sequencing confirmed that a significant fraction of MFS and UPS patient samples (n = 94) harbor chromosomal deletions and/or loss-of-function mutations in RB1 and TP53 (88% carry alterations in at least one gene; 60% carry alterations in both). Tissue microarray analysis identified a correlation between absent Rb and p53 expression and positive expression of Skp2. Downregulation of Skp2 or treatment with the Skp2-specific inhibitor C1 revealed that Skp2 drives proliferation of patient-derived MFS/UPS cell lines deficient in both Rb and p53 by degrading p21 and p27. Inhibition of Skp2 using the neddylation-activating enzyme inhibitor pevonedistat decreased growth of Rb/p53-negative patient-derived cell lines and mouse xenografts. These results demonstrate that loss of both Rb and p53 renders MFS and UPS dependent on Skp2, which can be therapeutically exploited and could provide the basis for promising novel systemic therapies for MFS and UPS. SIGNIFICANCE: Loss of both Rb and p53 renders myxofibrosarcoma and undifferentiated pleomorphic sarcoma dependent on Skp2, which could provide the basis for promising novel systemic therapies.See related commentary by Lambert and Jones, p. 2437.

Postoperative complications and prognosis after lobar resection versus sublobar resection in elderly patients with clinical Stage I non-small-cell lung cancer

OBJECTIVES

The study aimed to investigate the outcomes of sublobar resection in elderly patients with non-small-cell lung cancer.

METHODS

A total of 205 patients aged ≥75 years were identified from 794 consecutive patients who underwent complete surgical resection for clinical Stage I non-small-cell lung cancer. The outcomes of lobectomy and sublobar resection were compared. Propensity scores were estimated for multivariable analyses and matching.

RESULTS

Sublobar resection (n = 99) was more frequently performed than lobectomy (n = 106) in older patients (P = 0.027) and those with lower maximum standardized uptake on positron emission tomography (P < 0.001), lower T stage (P < 0.001), lower %vital capacity (P = 0.007) and lower %diffusing capacity of the lungs for carbon monoxide (P = 0.025). Severe (≥Grade IIIa) postoperative complications occurred more frequently with lobectomy (11 of 106 procedures, 10.4%) than with sublobar resection (5 of 99, 5.1%; P = 0.16). In propensity score-adjusted multivariable analysis, lobectomy was an independent predictive factor for severe postoperative complications (odds ratio 3.49, 95% confidence interval 1.01-12.05; P = 0.048). Overall survival (OS) was not significantly different following lobectomy (5-year OS 67.2%) or sublobar resection (5-year OS 73.9%; P = 0.93). In multivariable analysis, the surgical procedure was not an independent predictive factor for OS (lobectomy: hazard ratio 1.03, 95% confidence interval 0.49-2.16; P = 0.94).

CONCLUSIONS

Sublobar resection may be the optimal procedure in elderly patients with clinical Stage I non-small-cell lung cancer and is associated with less severe postoperative complications than lobectomy and similar OS.

Prolonged post-recurrence survival following pleurectomy/decortication for malignant pleural mesothelioma

The present study analyzed surgical results in patients with malignant pleural mesothelioma (MPM) who underwent extrapleural pneumonectomy (EPP) or pleurectomy/decortication (P/D). Data for 44 patients who achieved macroscopic complete resection following neoadjuvant chemotherapy followed by EPP (n=29) or P/D (n=15) were reviewed. Patient demographics and oncological outcomes were compared between the EPP and P/D groups. The median overall (OS) and progression-free survival (PFS) times were 22 and 14 months, respectively. OS was significantly different between the EPP and P/D groups (median OS, 17 vs. 34 months; 5-year OS, 11 vs. 44%; P=0.019); no difference was noted in PFS (median PFS, 13 vs. 21 months; 5-year PFS, 11 vs. 17%; P=0.373). Univariate analysis demonstrated that epithelial histology (P=0.0003) and P/D (P=0.018) were significant favorable prognostic factors for OS. Using multivariate analysis, epithelial histology (P=0.001) remained the only significant factor. Post-recurrence survival (PRS) among all patients was significantly longer in the P/D group (median PRS, 3 vs. 20 months; 1.5-year PRS, 5 vs. 54%; P=0.003), even among patients with epithelial-type MPM (median PRS, 6 s vs. 20 months; 1.5-year PRS, 8 vs. 61%; P=0.012). Chemotherapy following recurrence (P=0.033) was significantly associated with superior PRS in multivariate analysis. Postoperative pulmonary function was significantly improved in the P/D group. In summary, P/D may be an alternative procedure to EPP for resectable MPM providing similar PFS and improved PRS.

Therapeutic strategies and genetic profile comparisons in small cell carcinoma and large cell neuroendocrine carcinoma of the lung using next-generation sequencing

Small cell lung cancer (SCLC) and large cell neuroendocrine carcinoma (LCNEC) of the lung are classified as variants of endocrine carcinoma and subdivided into pure or combined type. Clinical benefit of target therapy has not been established in these tumors. This study aimed to compare genetic and clinicopathological features between SCLC and LCNEC or pure and combined types, and explore the possibility of target therapy using next-generation sequencing. In 13 SCLC and 22 LCNEC cases, 72 point mutations, 19 deletions, and 3 insertions were detected. As therapeutically targetable variants, mutations in EGFR (L858R), KRAS (G12D, G12A, G12V), and PIK3CA (E545K) were detected in 5 cases. The case harboring EGFR mutation showed response to EGFR-tyrosine kinase inhibitor. However, there are no clinicopathological features associated with therapeutically targetable cases. And there was no significant genetic feature between SCLC and LCNEC or pure and combined types. In conclusion, although patients with SCLC and LCNEC may benefit from target therapy, they were not identifiable by clinicopathologic background. And there was not significant genetic difference between SCLC and LCNEC, including between pure and combined types. Classifying SCLC and LCNEC in same category is reasonable. However, distinguishing the pure type from combined type was not validated. Comprehensive genetic analysis should be performed to detect targetable variants in any type of SCLC and LCNEC.

[Abdominoperineal Resection for Anal Metastasis of Rectal Cancer]

Anal metastasis of colorectal cancer is rare, and no standardized effective therapeutic strategy exists. We report a case of abdominoperineal resection for anal metastasis of rectal cancer. A 65-year-old man underwent laparoscopic low anterior resection for rectal cancer in August 2013. Histopathological examination revealed a moderately differentiated adenocarcinoma( tub2, pSS, ly3, v2, pN1, H0, P0, M0, Stage III a, Cur A). In February 2015, he complained of anal discomfort, and tumor markers were elevated. Enhanced CT revealed a 15-mm high-density solid tumor in the anal canal. The results of needle biopsy indicated a moderately differentiated adenocarcinoma. This tumor was suspected to be metastasis from rectal cancer, and we performed abdominoperineal resection. Histopathological examination revealed a moderately differentiated adenocarcinoma, which was the same histological type as the primary rectal cancer and was covered with normal anal epithelium. Collectively, the findings indicated anal metastasis from rectal cancer. The patient is alive without recurrence for 18 months after resection. Anal metastasis should be considered as a differential diagnosis in patients with anal discomfort who have a history of colon/rectal cancer. Abdominoperineal resection may be an effective treatment modality for this condition.

Outcomes of flexor tendon repairs in zone 2 subzones with early active mobilization

We report on the outcomes of flexor tendon repair in zone 2 subzones with early active mobilization in 102 fingers in 88 consecutive patients. There were 28, 53, 15, and six fingers with repairs in zones 2A to 2D, respectively. Rupture of the repair occurred in four fingers, all in zone 2B. Excluding those with repair ruptures, the mean total active motion was 230° (range 143°-286°). Evaluated with Tang's criteria, the outcomes were ranked excellent in 39 fingers, good in 46, fair in ten, poor in three, and failure in four. The outcomes in zone 2C were significantly inferior to those in zones 2B and 2D ( p = 0.02). Our results suggest that the tendon laceration in the area covered by the A2 pulley (zone 2C) is the most difficult area to obtain satisfactory active digital motion and tendon repair in zone 2B is the area where the risk of rupture is highest.

LEVEL OF EVIDENCE

IV.

Clinical Prognosis of Superior Versus Basal Segment Stage I Non-Small Cell Lung Cancer

BACKGROUND

Despite its extensive size, variations in the clinicopathologic features of tumors in the lower lobe have been little studied. The present study investigated the prognostic differences in tumors originating from the superior and basal segments of the lower lobe in patients with non-small cell lung cancer.

METHODS

Data of 134 patients who underwent lobectomy or segmentectomy with systematic nodal dissection for clinical stage I, radiologically solid-dominant, non-small cell lung cancer in the superior segment (n = 60) or basal segment (n = 74) between April 2007 and December 2015 were retrospectively reviewed. Factors affecting survival were assessed by the Kaplan-Meier method and Cox regression analyses.

RESULTS

Prognosis in the superior segment group was worse than that in the basal segment group (5-year overall survival rates 62.6% versus 89.9%, p = 0.0072; and 5-year recurrence-free survival rates 54.4% versus 75.7%, p = 0.032). In multivariable Cox regression analysis, a superior segment tumor was an independent factor for poor overall survival (hazard ratio 3.33, 95% confidence interval: 1.22 to 13.5, p = 0.010) and recurrence-free survival (hazard ratio 2.90, 95% confidence interval: 1.20 to 7.00, p = 0.008). The superior segment group tended to have more pathologic mediastinal lymph node metastases than the basal segment group (15.0% versus 5.4%, p = 0.080).

CONCLUSIONS

Tumor location was a prognostic factor for clinical stage I non-small cell lung cancer in the lower lobe. Patients with superior segment tumors had worse prognosis than patients with basal segment tumors, with more metastases in mediastinal lymph nodes.

Is cancer history really an exclusion criterion for clinical trial of lung cancer? Influence of gastrointestinal tract cancer history on the outcomes of lung cancer surgery

Objective

Exclusion of patients with a history of other cancer treatment except in situ situation has been considered to be inevitable for clinical trials investigating survival outcome. However, there have been few reports confirming these influences on surgical outcome of lung cancer patients ever.

Methods

Multi-institutional, individual data from patients with non–small cell lung cancer resected between 2000 and 2013 were collected. The patients were divided into two groups: those with a history of gastrointestinal tract cancer (GI group) and those without any history (non-GI group). We compared the outcomes with well-matched groups using propensity scoring to minimize bias related to the nonrandomness. The influence of gastrointestinal tract cancer stage, disease-free interval, and treatment method for gastrointestinal tract cancer on the surgical outcome of non–small cell lung cancer was examined.

Results

We analyzed 196 patients in the GI group and 3732 in the non-GI group. In unmatched cohort, multivariate analyses showed that a history of gastrointestinal tract cancer did not affect overall survival or recurrence-free survival. Independent predictors of poor prognosis included older age, male sex, high carcinoembryonic antigen levels and advanced clinical stage of non–small cell lung cancer. The two groups in the matched cohort demonstrated equivalent overall survival and recurrence-free survival, even in patients with clinical stage I. Gastrointestinal tract cancer stage, disease-free interval and treatment method for gastrointestinal tract cancer were not associated with outcomes.

Conclusions

History of early gastrointestinal tract cancer completely resected is not always necessary for exclusion criteria in clinical trial of lung cancer.

[Anomalous Systemic Arterialization of a Normal Basal Lung Segment with Aneurysm of the Aberrant Artery]

A 40-year-old woman was noted to have clubbing of the nails during an outpatient service for smoking cessation. Chest computed tomography showed an aneurysm of an aberrant artery running from the descending aorta to the left lower lobe. Hence, we diagnosed anomalous systemic arterialization of the lung. The proximal part of the aberrant artery measured 13 mm in diameter;moreover, it had developed an aneurysm(17 mm in diameter) in the lung parenchyma. The aberrant artery was ligated with a covering material (absorbable felt) and cut via a small access thoracotomy by a cardiovascular surgeon;subsequently, left lower lobectomy was performed. Pathological examination revealed significant atherosclerosis in the aberrant artery, demonstrating its severe fragility. To apply appropriate safety procedures and approaches are recommended when treating an aberrant artery to the lung, especially in the presence of an aneurysm.

Clinical results of releasing the entire A2 pulley after flexor tendon repair in zone 2C

We report the results of complete release of the entire A2 pulley after zone 2C flexor tendon repair followed by early postoperative active mobilization in seven fingers and their comparisons with 33 fingers with partial A2 pulley release. In seven fingers, release of the entire A2 pulley was necessary to allow free gliding of the repairs in five fingers and complete release of both the A2 and C1 pulleys was necessary in two. No bowstringing was clinically evident in any finger. Two fingers required tenolysis. Using Tang's criteria, the function of two digits was ranked as excellent, four good and one fair; there was no failure. The functional return in these seven fingers was similar with that in 33 fingers with partial A2 pulley release; in these patients only one finger required tenolysis. Our results support the suggestion that release of the entire A2 pulley together with the adjacent C1 pulley does not clinically affect finger motion or cause tendon bowstringing, provided that the other pulleys are left intact.

LEVEL OF EVIDENCE

IV.

Epithelioid sarcoma-like hemangioendothelioma on the chest wall

Epithelioid sarcoma-like hemangioendothelioma is a rare vascular neoplasm that usually occurs in the distal extremities of young adults. Although the overall behavior of this neoplasm is usually indolent with a low risk of distant metastasis, the risk of local recurrence is significant. Therefore, initial surgical treatment with an adequate margin is important to improve the prognosis. However, epithelioid sarcoma-like hemangioendothelioma is frequently misdiagnosed. A preoperative misdiagnosis could result in resection without a sufficient margin. Herein, we describe a 68-year-old man with epithelioid sarcoma-like hemangioendothelioma on the chest wall, which was treated by wide resection despite difficulties with the preoperative diagnosis.

[Tracheal Resection and Primary Anastomosis for Adenoid Cystic Carcinoma Using an Extracorporeal Membrane Oxygenation]

We report a case of tracheal resection and primary anastomosis for adenoid cystic carcinoma using an extracorporeal membrane oxygenation (ECMO). A 45-year-old female was referred to our hospital because of a tracheal tumor that occupied most of the tracheal lumen. In case of airway obstruction by the tracheal tumor during anesthesia and operation, we decided to use ECMO before induction of general anesthesia. Under secure respiratory control using ECMO, tracheal resection and primary anastomosis was performed. Since histopathological examination revealed microscopically positive results at the surgical margin, postoperative adjuvant radiation therapy( 60 Gy/30 Fr) was conducted. Although a tracheal tumor is a relatively rare neoplasm, careful planning and a treatment strategy are necessary with special emphasis on the location and size of tumor. In this case, ECMO made a substantial contribution to secure respiratory control during surgery.

Outcomes of release of the entire A4 pulley after flexor tendon repairs in zone 2A followed by early active mobilization

We report the outcomes of repair of the flexor digitorum profundus tendon in zone 2a in 22 fingers. The tendon was repaired with a six-strand repair method and the A4 pulley was completely released. Release of the C2 pulley combined with the A4 pulley was necessary in 12 fingers, nine fingers underwent a complete release of the A3, C2, and A4 pulleys, and one finger underwent a release of the C1, A3, C2, and A4 pulleys. The mean total active motion of the three finger joints was 234° at 5 to 12 months of follow-up. No bowstringing was noted in these fingers. The good and excellent recovery of active digital motion was in 20 (91%) out of 22 fingers according to Strickland's criteria or Tang's criteria. Our results suggest that release of the A3, C2, and A4 pulleys makes the repair surgery easier and does not cause tendon bowstringing.

[Assessment of Feasibility of Early Ambulation and Food-intake on the Operative Day after Lung Resection]

To decrease the risk of morbidity, we have started an early ambulation and food-intake program conducted on the same day as pulmonary resection. This protocol was developed with consideration of the characteristics of lung surgery and conducted through an interdisciplinary team-approach. The assessment of feasibility and clinical effectiveness of this protocol was evaluated in 64 consecutive patients. No apparent adverse effect relating to this protocol was recorded. Fifty-five of 64 patients( 80%) were able to accomplish ambulation to the up-right standing position. Thirty-four of 64 patients( 53%) were able to consume more than half the amount of their hospital supper. No patients, including 5 patients who had had a past-history of postoperative delirium after their previous surgery, developed postoperative delirium after conducting this protocol. This protocol, which consisted of extraordinary early ambulation and food-intake on the operative day, was done safely and is expected to have some benefit as a postoperative management protocol for lung surgery.

Prognostic value of the new IASLC/ATS/ERS classification of clinical stage IA lung adenocarcinoma

OBJECTIVES

We analyzed and validated the prognostic utility of the new International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) for clinical stage IA lung adenocarcinoma (ADC) classification of adenocarcinoma (ADC).

METHODS

We retrospectively reviewed 347 patients with clinical stage IA nonmucinous ADC, who had undergone complete resection. The histological subtype was classified according to the predominant subtype, as proposed by the new IASLC/ATS/ERS ADC classification.

RESULTS

The histopathological subtypes, defined according to the new IASLC/ATS/ERS ADC classification, were ADC in situ (AIS) in 56 patients (16.1%), minimally invasive ADC (MIA) in 15 (4.3%), lepidic-predominant ADC in 109 (31.4%), papillary-predominant ADC in 70 (20.2%), acinar-predominant ADC in 61 (17.6%), solid-predominant ADC in 30 (8.6%), and micropapillary-predominant ADC in 6 (1.7%). The 5-year disease-free survival (DFS) rate was 100% for both AIS and MIA. All cases of recurrence involved invasive ADC. The 5-year DFS for lepidic-predominant ADC was 99.0%; acinar-predominant ADC, 82.4%; papillary-predominant ADC, 80.8%; solid-predominant ADC, 73.6%; and micropapillary-predominant ADC, 33.3%. The predominant subtype of ADC was significantly correlated with DFS (P<0.0001). Multivariate analysis indicated that the pathological stage was an independent predictor of DFS (P=0.031). Other independent predictors of increased risk of recurrence were the presence of vascular or lymphatic invasion (HR=4.96, P=0.001), and a pathological stage more advanced than IB (HR=2.87, P=0.010). The coincidence between the clinical stage and pathological stage was 79.8%. The stage migration was found in 53.3% of solid-predominat ADC and in 83.3% of micropapillary-predominant ADC.

CONCLUSION

The new IASLC/ATS/ERS ADC classification has prognostic value in predicting the recurrence and survival of patients with clinical stage IA ADC. The frequency of stage migration was found in more than half of solid and micropapillary predominant ADCs.

Clinical outcomes of early active mobilization following flexor tendon repair using the six-strand technique: short- and long-term evaluations

We evaluated the factors influencing outcomes of flexor tendon repair in 112 fingers using a six-strand suture with the Yoshizu #1 technique and early postoperative active mobilization in 101 consecutive patients. A total of 32 fingers had injuries in Zone I, 78 in Zone II, and two in Zone III. The mean follow-up period was 6 months; 16 patients (19 fingers) participated in long-term follow-up of 2 to 16 years. The total active motion was 230° SD 29°; it correlated negatively with age. The total active motion was 231° SD 28° after repair of the lacerated flexor digitorum superficialis tendon, and was 205° SD 37° after excision of the flexor digitorum superficialis tendon ends (p = 0.0093). A total of 19 fingers showed no significant increases in total active motion more than 2 years after surgery. The rupture rate was 5.4% in our patients and related to surgeons' level of expertise. Five out of six ruptured tendons were repaired by inexperienced surgeons. Level of Evidence IV.

Comparison of malignant grade between pure and partially invasive types of early lung adenocarcinoma

BACKGROUND

The present study investigates the malignant significance of lepidic component presence in predominantly invasive lung adenocarcinoma that comprise less than 50% lepidic growth of the tumor.

METHODS

Among 347 consecutive patients with completely resected clinical stage IA lung adenocarcinoma, we excluded those with adenocarcinoma in situ, minimally invasive, and lepidic predominant invasive adenocarcinoma. We finally assessed 167 patients with predominantly invasive lung adenocarcinoma. We analyzed the clinicopathologic characteristics and prognoses of patients with 49 pure invasive tumors without lepidic growth and 118 partially invasive tumors with lepidic growth.

RESULTS

Pure invasive tumors were associated with being male, small tumor size, high maximum standardized uptake, and pleural as well as lymphatic invasion. Nonetheless, the invasive component size of both tumor types was similar. The predominant subtypes of pure and partially invasive tumors, respectively, were papillary, 17 (34.7%) and 53 (44.9%); acinar, 10 (20.4%) and 51 (43.2%); solid, 19 (38.8%) and 11 (9.3%), and micropapillary 3 (6.1%) and 3 (2.5%; p < 0.001). Recurrence-free survival was significantly worse for patients with pure, compared with partially, invasive tumors (p = 0.045).

CONCLUSIONS

Among predominantly invasive stage IA lung adenocarcinomas, the malignant potential was higher for pure invasive tumors, and the prognosis was poorer than for partially invasive tumors when the invasive components were of equal sizes. The presence or absence of a lepidic component reflects a difference in subtype predominance and can help to decide the malignant grade of lung adenocarcinoma.