Risk assessments for broncho-pleural fistula and respiratory failure after lung cancer surgery by National Clinical Database Japan

Risk factors for bronchopleural fistula based on surgical procedure and sex in 4794 consecutive patients undergoing anatomical pulmonary resection

PURPOSE

Bronchopleural fistula (BPF) is a lethal complication, even in the modern era. Therefore, we investigated the details of patients with BPF to select an appropriate surgical strategy.

METHODS

This retrospective study included 4794 consecutive patients who underwent anatomical pulmonary resection between 2008 and 2022. We evaluated the predictors of BPF using a multivariable analysis and investigated the mortality and clinical course after BPF in detail.

RESULTS

BPF was observed in 32 patients (0.67%). In the multivariable analysis, the predictors for BPF were male sex (odds ratio [OR], 6.91), the body mass index (OR, 2.40), the vital capacity (%VC) (OR, 2.93), surgery performed (right lower lobectomy [OR, 10.92], right middle and lower lobectomy [OR, 6.97], and right pneumonectomy [OR, 16.68]), and additional resection of surrounding organs (OR, 3.47). Among the risk factors, surgery performed and male sex were very strong risk factors, with the frequency itself very low in females (0.1%). The 90-day mortality was 15.6%, and the 5-year overall survival in patients with BPF was 28.1%.

CONCLUSION

Our study revealed that independent risk factors and consideration of the surgical methods and sex might help determine whether or not special attention should be given to the bronchial stump, which will be of great help in surgical strategies.

Development of a novel material to promote wound healing at bronchial defects

BACKGROUND

Bronchopleural fistula (BPF) is a critical complication that may progress to pneumonia and empyema, but optimal treatment remains uncertain. Our purpose was to develop a novel material for bronchial occlusion that can be used to treat BPF by blocking airflow and promoting wound healing.

METHODS

Sponges were prepared in concentrations of 25, 40, and 50 mg/dL of silk-elastin by hydrophobic processing. Five adult Beagle dogs underwent right anterior lobectomy, and 5 underwent left posterior lobectomy. Silk-elastin sponges were placed at bronchial stumps of 8 dogs, and silicone plugs were placed at the stumps of 2 dogs as a control.

RESULTS

Postoperative complications were not observed, except in 1 dog in which the silicone plug had been placed and which had massive subcutaneous emphysema at 4 weeks after operation. Histologic examination revealed that stumps were covered with connective tissue and that there was more regeneration of airway epithelium in the silk-elastin sponge group than in the silicone plug group. There were increased numbers of myofibroblasts around the bronchial stump occluded by silk-elastin sponges at 2 weeks after placement, which completely disappeared after 2 months, during which abundant neovascularization occurred.

CONCLUSIONS

We showed that silk-elastin sponges can manage and promote regeneration of bronchial epithelium. Our results demonstrate that bronchial occlusion with a silk-elastin sponge is a promising option for treatment of BPF.

Clinicopathological features of male patients with breast cancer based on a nationwide registry database in Japan

BACKGROUND

Male breast cancer (MBC) is rare; however, its incidence is increasing. There have been no large-scale reports on the clinicopathological characteristics of MBC in Japan.

METHODS

We investigated patients diagnosed with breast cancer in the Japanese National Clinical Database (NCD) between January 2012 and December 2018.

RESULTS

A total of 594,316 cases of breast cancer, including 3780 MBC (0.6%) and 590,536 female breast cancer (FBC) (99.4%), were evaluated. The median age at MBC and FBC diagnosis was 71 (45-86, 5-95%) and 60 years (39-83) (p < 0.001), respectively. MBC cases had a higher clinical stage than FBC cases: 7.4 vs. 13.3% stage 0, 37.2 vs. 44.3% stage I, 25.6 vs. 23.9% stage IIA, 8.8 vs. 8.4% stage IIB, 1.9 vs. 2.4% stage IIIA, 10.1 vs. 3.3% stage IIIB, and 1.1 vs. 1.3% stage IIIC (p < 0.001). Breast-conserving surgery was more frequent in FBC (14.6 vs. 46.7%, p = 0.02). Axillary lymph node dissection was more frequent in MBC cases (32.9 vs. 25.2%, p < 0.001). Estrogen receptor(ER)-positive disease was observed in 95.6% of MBC and 85.3% of FBC cases (p < 0.001). The HER2-positive disease rates were 9.5% and 15.7%, respectively (p < 0.001). Comorbidities were more frequent in MBC (57.3 vs. 32.8%) (p < 0.001). Chemotherapy was less common in MBC, while endocrine therapy use was similar in ER-positive MBC and FBC. Perioperative radiation therapy was performed in 14.3% and 44.3% of cases.

CONCLUSION

Japanese MBC had an older age of onset, were more likely to be hormone receptor-positive disease, and received less perioperative chemotherapy than FBC.

Successful use of bio plugs for delayed bronchial closure after pneumonectomy in experimental settings

OBJECTIVES

Cell therapies, such as stem cell suspension injection, are used to treat bronchopleural fistula. Although it is safe and effective, injected cells cannot remain within the bronchioles of the fistula due to cell leakage into the thoracic cavity. Here, we inserted a 'bio plug' into the fistula, produced using cells and a bio-3D printer, to examine the effectiveness of bio plugs for the closure of bronchopleural fistulas, the optimal cell source and the closure mechanism.

METHODS

Bio plugs were made with mesenchymal stem (stromal) cells derived from bone marrow (MSCBM), fibroblasts and rat lung micro-vessel endothelial cells using a bio-3D printer with different cell mixing ratios. Six groups, according to the presence or absence and the type of bio plugs, were compared. The plugs were inserted into the bronchi of F344 rats. The obstruction ratio and histological and immunohistochemical findings were evaluated.

RESULTS

MSCBM+ rat lung micro-vessel endothelial cell group exhibited a higher obstruction ratio among all groups excluding the MSCBM group (P = 0.039). This group had fibrosis and CD31-positive cells and fewer CD68-positive cells than MSCBM and MSCBM+ fibroblast groups.

CONCLUSIONS

Bio plugs with mixed cells, including stem cells, contribute to bronchial closure in the current experimental setting. Endothelial cells effectively maintain the structure in this model. Although bronchial closure for bronchopleural fistula could not be described as clinical conditions were not reproduced, we collected essential data on bronchial closure; however, further experiments are warranted.

Changes in pedicle pericardial fat tissue around the anastomotic site after tracheobronchoplasty

PURPOSE

Pericardial fat is appropriate tissue to cover the bronchial anastomotic site because its harvesting is minimally invasive. We investigated the changes in pericardial fat tissue around the anastomotic site after pulmonary resection with tracheobronchoplasty.

METHODS

The subjects of this study were 43 lung cancer patients who underwent pulmonary resection with tracheobronchoplasty. We measured the maximum cross-sectional area and average computed tomography (CT) values of the pedicle pericardial fat pad around the anastomotic site 1 week and then 6 months after the operation.

RESULTS

The average volume of the residual pedicle pericardial fat pad 6 months postoperatively was 61%. A body mass index (BMI) < 21.2 kg/m² (P = 0.031) and a blood albumin level < 3.4 g/dl (P = 0.005) were significant predictors of pedicle flap shrinkage. Patients with fat tissue shrinkage had significantly elevated CT values 6 months postoperatively (P = 0.029), whereas those without shrinkage maintained low CT values.

CONCLUSIONS

Preoperative nutritional conditions, reflected in high BMI and blood albumin levels, correlated with a high residual pedicle pericardial fat pad. Conversely, patients with pedicle flap shrinkage had significantly increased CT values, suggesting that the fat might have taken on another form such as scar tissue.

Japanese Current Status of Curative-Intent Surgery for Malignant Pleural Mesothelioma

BACKGROUND

Few reports about surgical outcomes in malignant pleural mesothelioma (MPM) were based on reliable nationwide databases. Here we analyzed the incidence, surgical outcome, and operative risk factors using Japanese nationwide database.

METHODS

Characteristics and perioperative data from 622 patients who underwent curative-intent surgery for MPM between January 2014 and December 2017 were recorded from National Clinical Database of Japan. We analyzed the incidence, surgical outcomes, and risk factors for surgical complications after two surgical procedures (extrapleural pneumonectomy, EPP; and pleurectomy/decortication, P/D).

RESULTS

During 4 years, EPP was performed in 279 patients and P/D in 343. EPP was more frequently performed in less-MPM-experienced institutions, while P/D was more frequently performed in well-MPM-experienced institutions (P < .001), especially in high-volume centers with more than 10 cases during this period. P/D was more frequently performed, especially in high-volume centers. The morbidity rates were 45.2% in EPP and 35.9% in P/D. Heart failure and pneumonia were most frequent in EPP, while prolonged air leakage was most frequent in P/D. Thirty-day- and in-hospital mortality rates were 1.1% and 3.2% (EPP) and 1.2% and 3.2% (P/D), respectively. Regression analyses revealed that higher age (>65 years) was associated with operative complications in EPP (odds ratio, OR: 3.56 [1.26-8.56]), whereas no risk factor was observed in P/D.

CONCLUSIONS

In Japanese nationwide annual database, P/D was more frequently performed, especially in high-volume centers. Morbidity was higher in EPP than P/D; however, the mortality rates were quite low in Japan regardless surgical procedures.

Autologous Multilayered Fibroblast Sheets Can Reinforce Bronchial Stump in a Rat Model

Bronchopleural fistula is one of the most serious postoperative complications caused by the incomplete healing of a bronchial stump. Fibroblasts play an important role in wound healing by facilitating connective tissue formation and inducing angiogenesis. We developed a method for production of multilayered fibroblast sheets that secreted some growth factors and promoted wound healing. The present study aimed to assess the treatment effect of multilayered fibroblast sheets on bronchial stump healing. In this rat model, left pneumonectomy was performed, and multilayered fibroblast sheets derived from autologous oral mucosal tissues were transplanted to the bronchial stump. The changes in the bronchial stump were examined macroscopically, histologically, and mechanically. The fibroblast sheets promoted the formation of thick connective tissues around the bronchial stump. The formed connective tissues were accompanied by new blood vessels, and fibrosis was observed over time. Then, 7 days after the transplantation of the fibroblast sheets, the bronchial wall became significantly thicker, and the area of the blood vessels for the bronchial wall tissues was significantly larger in the experimental group than in the control group. In addition, the burst pressure in the bronchial stump was significantly higher in the experimental group than in the control group. Bronchial stumps were reinforced by the transplantation of multilayered fibroblast sheets derived from autologous oral mucosal tissues.

Negative-pressure wound therapy in combination with bronchial occlusion to treat bronchopleural fistula: a case report

Background

Bronchopleural fistula, which usually accompanies bronchial fistula and empyema, is a severe complication of lung cancer surgery. Negative-pressure wound therapy can enhance drainage and reduce the empyema cavity, potentially leading to early recovery. This therapy is not currently indicated for bronchopleural fistulas because of the risk of insufficient respiration due to air loss from the fistula.

Case presentation

A 73-year-old man, who was malnourished because of peritoneal dialysis, was referred to our hospital for the treatment of lung cancer. Right lower lobectomy with mediastinal lymph node dissection was performed via posterolateral thoracotomy, and the bronchial stump was covered with the intercostal muscle flap. His postoperative course was uneventful and he was discharged. However, he was readmitted to our hospital because of respiratory failure and diagnosed as having bronchopleural fistula on the basis of the bronchoscopic finding of a 10-mm hole at the membranous portion of the inlet of the remnant lower lobe bronchus. Thus, thoracotomy debridement and open window thoracostomy were immediately performed. After achieving infection control, bronchial occlusion was performed using fibrin glue and a polyglycolic acid sheet was inserted through a fenestrated wound. Bronchial fistula closure was observed on bronchoscopy; therefore, a negative-pressure wound therapy system was applied to close the fenestrated wound. The collapsed lung was re-expanded and the granulation tissue around the wound increased; therefore, thoracic cavity size decreased and thoracoplasty using the latissimus dorsi was performed.

Conclusions

This bronchopleural fistula was treated successfully after a right lower lobectomy using an extra-pleural bronchial occlusion and negative-pressure wound therapy.

Preoperative Cumulative Smoking Dose on Lung Cancer Surgery in a Japanese Nationwide Database

BACKGROUND

Smoking is a known risk factor for postoperative mortality and morbidity. However, the significance of cumulative smoking dose in preoperative risk assessment has not been established. We examined the influence of preoperative cumulative smoking dose on surgical outcomes after lobectomy for primary lung cancer.

METHODS

A total of 80,989 patients with primary lung cancer undergoing lobectomy from 2014 to 2016 were enrolled. Preoperative cumulative smoking dose was categorized by pack-years (PY): nonsmokers, PY = 0; light smokers, 0 < PY < 10; moderate smokers, 10 ≤ PY < 30; and heavy smokers, 30 ≤ PY. The risk of short-term outcomes was assessed according to PY by multivariable analysis adjusted for other covariates.

RESULTS

Postoperative 30-day mortality, as well as pulmonary, cardiovascular, and infectious complications, increased with preoperative PY. Multivariable analysis revealed that the odds ratios (ORs) for postoperative mortality compared with nonsmokers were 1.76 for light smokers (P = .044), 1.60 for moderate smokers (P = .026), and 1.73 for heavy smokers (P = .003). The ORs for pulmonary complications compared with nonsmokers were 1.20 for light smokers (P = .022), 1.40 for moderate smokers (P < .001), and 1.72 for heavy smokers (P < .001). Heavy smokers had a significantly increased risk of postoperative cardiovascular (OR, 1.26; P = .002) and infectious (OR, 1.39; P = .007) complications compared with nonsmokers.

CONCLUSIONS

The risk of mortality and morbidity after lung resection could be predicted according to preoperative cumulative smoking dose. These findings contribute to the development of strategies in perioperative management of lung resection patients.

Certified thoracic surgeons in Japan: a national database survey on risk-adjusted mortality associated with lung resection

PURPOSE

We investigated the association between the number of certified general thoracic surgeons (GTSs) and the mortality after lung cancer surgery, based on the data from the National Clinical Database (NCD).

METHODS

We analyzed the characteristics and operative and postoperative data of 120,946 patients who underwent lung cancer surgery in one of the 905 hospitals in Japan. The number of GTSs in each hospital was categorized as 0, 1-2, or 3 or more. Multivariable analysis was applied to adjust the patients' preoperative risk factors, as identified in a previous study. We calculated 95% confidence intervals (CI) for the mortality rate based on the odds ratios (ORs).

RESULTS

The patients' characteristics were distributed almost uniformly regardless of the number of GTSs. Crude mortality according to the number of GTSs of 0, 1-2, or 3 or more was 0.9%, 0.8%, and 0.7%, respectively (p = 0.03). However, after adjustment, the ORs for 1-2 and 3 or more GTSs (reference: 0) were 0.86 (p = 0.23, 95% CI: 0.67-1.10) and 0.84 (p = 0.18, 95% CI: 0.64-1.09), respectively. The number of GTSs did not have a significant association with mortality. Similar results were observed for patients in the lobectomy cohort.

CONCLUSION

Low surgical mortality was consistent, regardless of the number of GTSs in each hospital.

Advantages and disadvantages of corticosteroid use for acute exacerbation of interstitial pneumonia after pulmonary resection

OBJECTIVES

Acute exacerbation of interstitial pneumonia (AE-IP) is the top cause of 30-day mortality in surgery for lung cancer patients. The general treatment for AE-IP is corticosteroid; however, there are some disadvantages of corticosteroid use after surgery. This study was conducted to report the clinical course of AE-IP after surgery and evaluate the effect of corticosteroid use.

METHODS

This retrospective study was performed on 337 patients with interstitial pneumonia who underwent surgical resection for lung cancer at our institute between 2009 and 2018. AE-IP were observed in 14 patients (4.2%) and their management and clinical outcome were investigated.

RESULTS

All patients received methylprednisolone pulse therapy. Six patients (42.9%) became convalescent after pulse therapy and eight (57.1%) died within 90 days after surgery due to lack of therapeutic efficacy. Oxygenation and ground-glass opacities of the survivors improved within 3 days after starting pulse therapy. Patients who responded to the first pulse also responded to the second pulse. Four patients developed complications including two with bronchopulmonary fistulas that may be related to steroid treatment. Even if the corticosteroid was effective, all AE-IP patients died within 1 year after surgery.

CONCLUSIONS

Corticosteroid therapy is effective for AE-IP after surgery; however, it may lead to severe complications after surgery.

One-stage closure of large bronchopleural fistula with pedicled latissimus dorsi muscle flap after preemptive antibiotics: A case report

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Bronchopleural fistula (BPF) often needs two-stage closure after fenestration.

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This case highlights one-stage surgical closure of a large BPF with a muscle flap.

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Pedicled latissimus dorsi muscle flap would be useful even for 3-cm sized BPF.

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Preemptive antibiotics minimized local infection in ischemic bronchitis before BPF.

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Minimum infection with a limited-size space may be a key for one-stage closure.

Introduction

Bronchopleural fistula (BPF) after lung cancer surgery is a life-threatening complication and often needs two-stage closure after fenestration. Although one-stage closure of BPF is challenging, it would provide shorter treatment time and lower patient physical burden than two-stage closure. However, there have been few reports of one-stage closure of a large BPF.

Presentation of case

A 53-year-old man underwent robotic right lower lobectomy with systematic lymph node dissection. Postoperative bronchoscopy revealed an ischemic change in the bronchial stump, which progressed to a large BPF. However, under the preemptive antibiotic treatment without chest drainage, local infection was controlled within a limited pleural space. We successfully performed one-stage closure of a 3-cm sized BPF with pedicled latissimus dorsi (PLD) muscle flap.

Discussion

Early diagnosis of ischemic bronchitis and appropriate preceding antibiotic treatment could minimize the local infection around the fistula. To our knowledge, our case represented the largest BPF that was successfully treated by one-stage procedure using preemptive antibiotics and the PLD muscle flap.

Conclusion

One-stage closure using the PLD muscle flap may be a treatment option even for a 3-cm sized BPF, wherein infection is controlled and the relevant pleural cavity is limited.

Analysis of Risk Factors for Bronchopleural Fistula after Surgical Treatment of Lung Cancer

PURPOSE

Bronchopleural fistula (BPF) is a potential serious complication of lobectomy or more radical surgery for non-small-cell lung cancer (NSCLC). We aimed to evaluate the risk factors for BPF.

METHODS

The study cohort comprised 635 patients who had undergone lobectomy or more radical surgery for NSCLC from March 2005 to December 2017. We examined the following risk factors for BPF: surgical procedure, medical history, preoperative treatment, and surgical management.

RESULTS

In all, 10 patients (1.6%) had developed postoperative BPFs. Univariate logistic regression analysis showed that surgical procedure, medical history (arteriosclerosis obliterans [ASO]), and bronchial stump reinforcement were significant risk factors. Multivariate analysis showed that only surgical procedure (right lower lobectomy, p = 0.011, odds ratio = 17.4; right middle lower lobectomy, p = 0.003, odds ratio = 59.4; right pneumonectomy, p <0.001, odds ratio = 166.0) was a significant risk factor. Multivariate analysis confined to the surgical procedure of lobectomy showed that right lower lobectomy (p = 0.011, odds ratio = 36.5) and diabetes (HbA1c ≥8.0) (p = 0.022, odds ratio = 31.7) were significant risk factors.

CONCLUSION

When lobectomy or more radical surgery is performed for NSCLC, right lower lobectomy, middle lower lobectomy, and right pneumonectomy are significant risk factors for postoperative BPF. Thoracic surgeons should acquire the techniques of bronchoplasty and angioplasty to avoid such invasive procedures.

Postoperative changes of the free pericardial fat pad for bronchial stump coverage

Background

Bronchopleural fistula (BPF) remains a serious complication after surgery for lung cancer with bronchial resection. A free pericardial fat pad (FPFP) is applied in high-risk cases to reduce BPF frequency. BPF may occur 6 months after surgery. Thus, we evaluated the residual FPFP volume at 6 months after surgery to estimate the residual FPFP ratio and determine the amount of FPFP to be harvested during surgery.

Methods

We retrospectively investigated 40 patients who underwent lobectomy with bronchial stump coverage using FPFP. During surgery, the volume of the harvested FPFP was measured and the FPFP was affixed to the bronchial stump. Further, 6 months after surgery, the residual volume of the installed FPFP was analyzed using a three-dimensional volume analyzer and the residual ratio was calculated. We also evaluated clinicopathological factors influencing the resected FPFP and residual ratio.

Results

The median resected FPFP volume was 11 [3-40] mL. During multivariate analysis, body mass index and surgical approach were found to be significant factors associated with the resected FPFP volume. The median residual FPFP volume was 4.3 (0.4-15.5) mL. The median residual ratio was 0.39 (0.13-0.66). The resected FPFP volume was significantly associated with the residual volume (P<0.001) but not with the residual ratio (P=0.811). No factor was associated with the residual ratio.

Conclusions

In all cases, residual FPFP was confirmed at 6 months after surgery and the residual ratio was 40%. It is necessary to determine the volume of FPFP to be harvested while carefully considering the shrinkage ratio.