鈴木 秀海

The relationship between cancer prognosis and intratumoral microbiome has recently gained attention. Regarding lung cancer, most studies have focused on bacteria outside tumors, such as sputum or lavage fluid, with few examining intratumoral bacteria and their impact on prognosis. In this study, we extracted DNA from lung tumor samples of 507 patients undergoing surgery at Chiba University Hospital and quantified intratumoral bacterial abundance using bacteria-specific PCR primers. Bacteria were detected in 77.1% of cases, and bacterial abundance was significantly higher in lung adenocarcinoma than in squamous cell carcinoma. Patients were categorized into three groups (High, Low, and Very-Low) based on bacterial abundance, and associations with clinicopathological factors were analyzed. In lung squamous cell carcinoma, higher bacterial abundance was significantly associated with worse recurrent-free survival and overall survival and was found to be a poor prognostic factor independent of pathological tumor stage. In conclusion, intratumoral bacterial abundance was found in the majority of lung cancer tissues, with variations based on pathology. This abundance may serve as a useful marker for stratifying lung squamous cell carcinoma with distinct prognoses.

BACKGROUND: Air leakage during pulmonary resection is a major complication in thoracic surgery. It frequently occurs at sites of adhesion dissection, due to lung manipulation, and along the staple lines of automatic suturing devices, particularly in cases of pulmonary fragility such as those of emphysema and interstitial pneumonia. Persistent postoperative air leakage prolongs chest tube indwelling and extends hospitalization time. Staplers with absorbable tissue reinforcements have been introduced for pulmonary resection to prevent intraoperative stapler-related air leakage. This phase II prospective, open-label, randomized, parallel-group trial aims to validate the efficacy of staplers with or without absorbable tissue reinforcements in controlling stapler-related air leakage during anatomical pulmonary resections. METHODS: Overall, 120 patients will be randomized into two groups: one that will undergo conventional anatomical pulmonary resection and the other in which staplers with absorbable tissue reinforcements will be used. The primary endpoint will be intraoperative stapler-related air leakage. Data will be analyzed between 2024 and 2025. DISCUSSION: This trial will validate the effectiveness and safety of staple line reinforcements in controlling intraoperative air leakage during anatomical pulmonary resections, potentially leading to optimized strategies for patients with conditions such as emphysema and interstitial pneumonia. TRIAL REGISTRATION: This trial has been registered with the Japan Registry of Clinical Trials 1032220620 ( https://jrct.niph.go.jp/latest-detail/jRCTs031230224 ).

BACKGROUND: According to a large-scale clinical trial in Japan, segmentectomy for small peripheral non-small cell lung cancer has an advantage over lobectomy in terms of overall survival, while it could also increase the incidence of local recurrence. In ipsilateral reoperations, intrathoracic adhesions from a previous surgery increase the risk of lung injury and bleeding, which may result in intraoperative and postoperative complications. The ability of oxidized regenerated cellulose (ORC) sheets to prevent postoperative adhesions has been demonstrated in the abdomen, and the same effect is expected in the thoracic region. The purpose of this study is to provide evidence supporting the application of ORC sheets to the parietal pleura of an open chest wounds to prevent postoperative adhesions in the thoracic region. METHODS: This phase II prospective open-label, randomized, parallel-group study will validate adhesion prevention by applying ORC sheets to the parietal pleura of open chest wounds at the time of surgical closure. In the control group, the chest is closed by the usual procedure without ORC sheets. The primary endpoint is the presence rate of pleural adhesion findings on chest echography performed 4-20 weeks postoperatively. Data analysis will be performed in 2025-2026. DISCUSSION: This study will provide evidence to the adhesion prevention effect of ORC sheet in the thoracic region, with the aim of establishing a strategy to prevent postoperative intrapleural adhesions. TRIAL REGISTRATION: This trial has been registered on the Japan Registry of Clinical Trials 1032230271 (https://jrct.niph.go.jp/latest-detail/jRCT1032230271).

BACKGROUND: Sarcomatoid carcinoma of the lung is a rare histological type of non-small cell lung cancer with a poor prognosis. We aimed to investigate the clinicopathological characteristics and prognostic factors of surgically resected sarcomatoid carcinoma of the lung. METHODS: We retrospectively reviewed 14999 patients who underwent surgical resection for non-small cell lung cancer accumulated by the Japanese Joint Committee of Lung Cancer Registry in 2010. Clinicopathological characteristics and survival were compared between the sarcomatoid carcinoma and other non-small cell cancer groups. The prognostic factors in the sarcomatoid carcinoma group were identified using a multivariate Cox proportional hazard model. RESULTS: Patients with sarcomatoid carcinoma comprised 1.4% of all patients. The sarcomatoid carcinoma group demonstrated a more aggressive pathology with presentation at more advanced stages, requiring more frequent extensive surgical resections. The sarcomatoid carcinoma group had remarkably poorer overall and recurrence-free survival than the other non-small cell lung cancer group. Adjuvant chemotherapy was associated with improved survival for pathological stage II-III sarcomatoid carcinoma cases rather than for pathological stage I disease. In the multivariate analysis, larger tumor size, lymphatic permeation, and no adjuvant chemotherapy were associated with the sarcomatoid carcinoma group's overall and recurrence-free survival. CONCLUSIONS: Surgically resected sarcomatoid carcinoma of the lung has a higher aggressive and metastatic potential and a worse prognosis than other non-small cell lung cancers. Adjuvant chemotherapy, which was associated with enhanced survival in patients with pathological stage II-III of the disease, could be considered for treating patients with pathological stage II-III sarcomatoid carcinoma of the lung.