Taketsugu Yamamoto

Prognostic value of the IASLC/ATS/ERS classification of lung adenocarcinoma in stage I disease of Japanese cases

A new classification of adenocarcinoma (ADC) was proposed by the International Association for the Study of Lung Cancer, the American Thoracic Society, and the European Respiratory Society (IASLC/ATS/ERS) in 2011. The present study evaluates its prognostic value in stage I disease of Japanese cases. One‐hundred‐and‐seventy‐nine cases with pathological stage I ADC were classified according to the new classification system and their association with disease recurrence was analyzed. Eighteen (10.1%) and 24 (13.4%) cases were adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA), respectively. One‐hundred‐and‐thirty‐seven cases (76.5%) were invasive adenocarcinoma (IVA), in which 43 (24.0%) were lepidic (LEP), 59 (33.0%) were acinar (ACN), 16 (8.9%) were papillary (PAP), 1 (0.6%) was micropapillary (MPAP), 12 (6.7%) were solid predominant subtypes (SOL), and 6 (3.4%) were invasive mucinous adenocarcinoma (MUC). The5‐year disease‐free survivals (DFS) of patients with AIS and MIA were 100%. Those of LEP, ACN, PAP, SOL and MUC were 93.5%, 83.7%, 75.0%, 44.4% and 62.5%, respectively. Multivariate analysis showed that high‐histological grade (SOL, MPAP, MUC) had an independent prognostic value to predict post‐operative recurrence (HR 3.661, 95% CI 1.421–9.437, P = 0.007). In conclusion, the present study demonstrates a prognostic value of the 2011 IASLC/ATS/ERS classification of ADC in Japanese cases.

Influence of visceral pleural invasion on survival in completely resected non-small-cell lung cancer

OBJECTIVES Although the prognostic implications of visceral pleural invasion (VPI) are well established, it remains controversial whether the extent of VPI affects survival in patients with completely resected non-small-cell lung cancer (NSCLC). In addition, the impact of VPI according to nodal status is unclear. We evaluated the influence of the extent of pleural invasion on survival by analysing a multicentre retrospective database of patients who had undergone surgery for NSCLC. METHODS We retrospectively reviewed the clinicopathological characteristics and outcomes of 639 patients with NSCLC who underwent anatomic complete resection from 2005 to 2007 at nine hospitals affiliated with the Yokohama Consortium of Thoracic Surgeons. RESULTS The median follow-up was 65.0 months. The extent of pleural invasion was PL0 in 462 patients, PL1 in 135 and PL2 in 42. The 5-year overall survival rate was significantly higher in patients with PL0 tumours (75.9%) than in those with PL1 (63.6%) or PL2 tumours (54.1%). On subgroup analysis according to nodal status, PL0 was associated with a higher survival rate than that of PL1 or PL2 tumours in patients with N0 or N1 metastasis, but not in those with N2 metastasis. There was no difference between PL1 and PL2 in any subgroup. CONCLUSIONS Our results suggest that the presence of VPI, rather than the extent, has an impact on postoperative survival in patients with NSCLC who have N0 or N1 metastasis. Because very few previous studies have addressed the effects of VPI in patients with N1 disease, further re-evaluation of the prognostic impact of VPI is necessary in this subgroup of patients.

Lobe-Specific Lymph Node Dissection as a Standard Procedure in Surgery for Non–Small Cell Lung Cancer: A Propensity Score Matching Study

Introduction: Systematic lymph node dissection (SND) is the standard procedure in surgical treatment for NSCLC, but the value of this approach for survival and nodal staging is still uncertain. In this study, we evaluated the potential of lobe‐specific lymph node dissection (L‐SND) in surgery for NSCLC by using a propensity score matching method. Methods: From 2005 to 2007, 565 patients with cT1a–2b N0–1 M0 NSCLC underwent lobectomy with lymph node dissection at our 10 affiliated hospitals. Patients were classified into groups that underwent nodal sampling, L‐SND, and systematic dissection SND on the basis of pathological data for the number and extent of nodal resection. A total of 77 patients with insufficient pathological data were excluded from the study. Results: Overall, survival did not differ significantly among the groups (p = 0.552), but the rate of detection of pN2 in the SND group (13.1%) was significantly higher than in the nodal sampling (3.3%) and L‐SND (9.0%) groups (p = 0.010). However, given the many confounding factors in the patient characteristics in each group, outcomes were reevaluated using a propensity score matching method for the L‐SND and SND groups. After matching, the two groups had no significant differences in 5‐year overall survival (73.5% for L‐SND versus 75.3% for SND, p = 0.977) and pN2 detection (8.2% in both groups, p = 0.779). Conclusions: These results suggest that lobe‐specific lymph node dissection has the potential to be a standard procedure in surgical treatment for NSCLC.

Postoperative follow-up strategy based on recurrence dynamics for non-small-cell lung cancer

OBJECTIVES Our study was designed to visually represent recurrence patterns after surgery for non-small-cell lung cancer (NSCLC) with the use of event dynamics and to clarify postoperative follow-up methods based on the times of recurrence. METHODS A total of 829 patients with NSCLC who underwent complete pulmonary resection from 2005 to 2007 in 9 hospitals affiliated with the Yokohama Consortium of Thoracic Surgeons were studied. Event dynamics, based on the hazard rate, were evaluated. Only first events involving the development of distant metastases, local recurrence or both were considered. The effects of sex, histological type, pathological stage and age were studied. RESULTS The hazard rate curve displayed an initial surge that peaked about 6-8 months after surgery. The next distinct peak was noted at the end of the second year of follow-up. On non-parametric kernel smoothing, the maximum peak was found 6-8 months after surgery in men. In women, the highest peak occurred 22-24 months after surgery, which was about 16 months later than the peak in men. The peak timing of the hazard curve was not affected by histological type, pathological stage or age in either sex. CONCLUSIONS Our results suggest that the timing of recurrence after surgery for lung cancer is characterized by a bimodal pattern, and the times with the highest risk of recurrence were suggested to differ between men and women. Postoperative follow-up strategies should be based on currently recommended follow-up programmes, take into account the recurrence patterns of lung cancer, and be modified as required to meet the needs of individual patients.

Assessment of spontaneous hemopneumothorax: Indications for surgery.

Background Although spontaneous hemopneumothorax is rare, emergency surgery may be necessary if massive bleeding is present. Methods We examined therapeutic strategies and outcomes as well as background factors in 16 patients with spontaneous hemopneumothorax treated at our hospital between April 2002 and August 2013. Results Emergency surgery was performed in 3 patients, all of whom were hemodynamically unstable. Elective surgery was performed in 7 patients, all of whom showed continuous bleeding from a pleural cavity drain. The surgery consisted of intrapleural hematoma removal, hemostasis, and bullectomy; 3-port thoracoscopy was used in all of the surgical cases. Six patients, none of whom showed continuous bleeding, recovered with conservative therapy. Comparing the conservative therapy and surgery groups revealed the mean continuous bleeding volume and total blood loss to be significantly greater in the latter, but no significant difference was noted between the two groups in terms of the initial bleeding volume following tube thoracostomy. None of the cases required a blood transfusion. Conclusions Spontaneous hemopneumothorax is not necessarily an indication for surgery, and even when the initial volume of blood drained through the chest tube is large, some patients can still be treated conservatively with careful monitoring of vital signs and continuous bleeding volumes. However, it is important not to miss the optimal timing of surgery in order to avoid administering unnecessary blood transfusions to young patients.

Giant solitary fibrous tumor with pulmonary vein pseudothrombus.

A 64-year-old woman with a solitary fibrous tumor was referred to our hospital. Enhanced computed tomography revealed a huge mass occupying the lower part of the right hemithorax, with a low-density area in the right inferior pulmonary vein. Tumor extension or thrombosis in the inferior pulmonary vein was suspected preoperatively (Figure 1). Surgery was performed under cardiopulmonary bypass, and the left atrium and inferior pulmonary vein were confirmed to be free of tumor and thrombus. The tumor was excised with the right lower lobe. The huge tumor had delayed the timing of contrast enhancement in the pulmonary vein, and the laminar flow in the pulmonary vein caused an artifact that simulated thrombosis or tumor extension.

Giant Desmoid Tumor of the Chest Wall

A 21-year-old man was referred to our hospital because of a right thoracic mass detected on a medical checkup. He was asymptomatic. There was no history of trauma or Gardner syndrome. Computed tomography revealed that the chest wall tumor involved the right first and second ribs (Figure 1A). The tumor occupied the right hemithorax and displaced the mediastinum to the left (Figure 1B). A combined clamshell incision and median sternotomy were performed. The tumor was resected en bloc with portions of the first rib, second rib, sternum, musculus pectoralis major, and clavicle. The chest wall was reconstructed with a 1-mm composite mesh (polypropylene/polytetrafluoroethylene). Mechanical ventilation was required for 2 weeks postoperatively because of respiratory failure. However, the patient recovered without any functional deficit. Histopathological examination confirmed a desmoid tumor measuring 23.5 18 11 cm and weighing 2800 g. The specimen showed proliferations of spindle-shaped cells with slight atypia in a collagenous stroma. The surgical margins were free of tumor (Figure 2). Desmoid tumors are relatively rare tumors derived from fascial or musculoaponeurotic structures. Pathologically they are benign but grow locally aggressive. If feasible, surgical resection of the tumor is the treatment of choice, but a high incidence of local recurrence has been reported.1,2 Reoperation and positive margins are associated with a high risk of local recurrence.1 Therefore, it is essential to achieve local control by wide resection with tumor-free margins on initial treatment.

Gender Differences in the Recurrence Timing of Patients Undergoing Resection for Non-Small Cell Lung Cancer

Objective: This study was designed to visually represent postoperative recurrence patterns using event dynamics and to assess sex-based differences in the timing of recurrence for non-small cell lung cancer. Methods: We studied 829 patients (538 men, 291 women) with NSCLC who underwent complete pulmonary resection in 9 hospitals. Event dynamics with the use of life-table methods were evaluated, and only first events (distant metastases or local recurrence) were considered. The effects of sex, histological type, pathological stage, and smoking history were studied. Result: The resulting smoothed hazard rate curves indicated that the recurrence risk pattern definitely correlated with sex, with a sharp peak in the first year in men and a broad peak during the first 2 to 3 years in women. These findings were also confirmed by analyses according to pathological stage, histological type, and smoking history. Conclusion: The peak times of recurrence differed considerably between men and women. The delayed time of peak recurrence in women, associated with a longer disease-free interval within subsets of patients with similar disease stage, histological type, and smoking status, might account for the better survival in women.

A case of pleomorphic carcinoma of the lung suspected from infectious bulla.

A 49-year-old man was referred with a complaint of fever. Chest computed tomography demonstrated a giant bulla forming an air-fluid level. He was diagnosed with infectious bulla, and treated with antibiotics. The cavitary mass changed to a solid mass over the next 3 months (Figure 1). Positron-emission tomographycomputed tomography showed high uptake of F in the right upper lobe mass (SUVmax 10.0). The patient underwent superior lobectomy of the right lung. Histopathologically, the tumor was pleomorphic carcinoma of the lung (Figure 2). That finding suggested that the carcinoma originated from the pulmonary bulla.