Comparative analysis of the bronchoalveolar microbiome in Portuguese patients with different chronic lung disorders.

The lung is inhabited by a diverse microbiome that originates from the oropharynx by a mechanism of micro-aspiration. Its bacterial biomass is usually low; however, this condition shifts in lung cancer (LC), chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD). These chronic lung disorders (CLD) may coexist in the same patient as comorbidities and share common risk factors, among which the microbiome is included. We characterized the microbiome of 106 bronchoalveolar lavages. Samples were initially subdivided into cancer and non-cancer and high-throughput sequenced for the 16S rRNA gene. Additionally, we used a cohort of 25 CLD patients where crossed comorbidities were excluded. Firmicutes, Proteobacteria and Bacteroidetes were the most prevalent phyla independently of the analyzed group. Streptococcus and Prevotella were associated with LC and Haemophilus was enhanced in COPD versus ILD. Although no significant discrepancies in microbial diversity were observed between cancer and non-cancer samples, statistical tests suggested a gradient across CLD where COPD and ILD displayed the highest and lowest alpha diversities, respectively. Moreover, COPD and ILD were separated in two clusters by the unweighted UniFrac distance (P value = 0.0068). Our results support the association of Streptoccocus and Prevotella with LC and of Haemophilus with COPD, and advocate for specific CLD signatures.

Is the Proteome of Bronchoalveolar Lavage Extracellular Vesicles a Marker of Advanced Lung Cancer?

Acellular bronchoalveolar lavage (BAL) proteomics can partially separate lung cancer from non-lung cancer patients based on principal component analysis and multivariate analysis. Furthermore, the variance in the proteomics data sets is correlated mainly with lung cancer status and, to a lesser extent, smoking status and gender. Despite these advances BAL small and large extracellular vehicles (EVs) proteomes reveal aberrant protein expression in paracrine signaling mechanisms in cancer initiation and progression. We consequently present a case-control study of 24 bronchoalveolar lavage extracellular vesicle samples which were analyzed by state-of-the-art liquid chromatography-mass spectrometry (LC-MS). We obtained evidence that BAL EVs proteome complexity correlated with lung cancer stage 4 and mortality within two years´ follow-up (p value = 0.006). The potential therapeutic target DNMT3B complex is significantly up-regulated in tumor tissue and BAL EVs. The computational analysis of the immune and fibroblast cell markers in EVs suggests that patients who deceased within the follow-up period display higher marker expression indicative of innate immune and fibroblast cells (four out of five cases). This study provides insights into the proteome content of BAL EVs and their correlation to clinical outcomes.

Unusual Behaviour Of A Lung Inflammatory Myofibroblastic Tumour.

Inflammatory myofibroblastic tumours (IMTs) are rare lesions. We report a case of a 55 year-old male, admitted with a pneumonia. Further investigation revealed a left lower lobe mass and enlarged mediastinal lymph nodes. Cytology of the bronchoalveolar lavage suggested a squamous cell carcinoma. He received four cycles of chemotherapy followed by a left lower lobectomy. Pathological analysis was compatible with IMT. Three months after surgery, a new IMT nodule located in the lingula was excised. Four months later,endobronchial involvement and the presence of liver nodules were detected.Ten months after the first surgery a CT revealed a sacrum lesion. Histology was compatible with undifferentiated sarcoma and a sarcomatous transformation was assumed.

Profiling of lung microbiota discloses differences in adenocarcinoma and squamous cell carcinoma.

The lung is a complex ecosystem of host cells and microbes often disrupted in pathological conditions. Although bacteria have been hypothesized as agents of carcinogenesis, little is known about microbiota profile of the most prevalent cancer subtypes: adenocarcinoma (ADC) and squamous cell carcinoma (SCC). To characterize lung cancer (LC) microbiota a first a screening was performed through a pooled sequencing approach of 16S ribosomal RNA gene (V3-V6) using a total of 103 bronchoalveaolar lavage fluid samples. Then, identified taxa were used to inspect 1009 cases from The Cancer Genome Atlas and to annotate tumor unmapped RNAseq reads. Microbial diversity was analyzed per cancer subtype, history of cigarette smoking and airflow obstruction, among other clinical data. We show that LC microbiota is enriched in Proteobacteria and more diverse in SCC than ADC, particularly in males and heavier smokers. High frequencies of Proteobacteria were found to discriminate a major cluster, further subdivided into well-defined communities' associated with either ADC or SCC. Here, a SCC subcluster differing from other cases by a worse survival was correlated with several Enterobacteriaceae. Overall, this study provides first evidence for a correlation between lung microbiota and cancer subtype and for its influence on patient life expectancy.

Bronchoalveolar Lavage Proteomics in Patients with Suspected Lung Cancer.

Lung cancer configures as one of the deadliest types of cancer. The future implementation of early screening methods such as exhaled breath condensate analysis and low dose computed tomography (CT) as an alternative to current chest imaging based screening will lead to an increased burden on bronchoscopy units. New approaches for improvement of diagnosis in bronchoscopy units, regarding patient management, are likely to have clinical impact in the future. Diagnostic approaches to address mortality of lung cancer include improved early detection and stratification of the cancers according to its prognosis and further response to drug treatment. In this study, we performed a detailed mass spectrometry based proteome analysis of acellular bronchoalveolar lavage (BAL) fluid samples on an observational prospective cohort consisting of 90 suspected lung cancer cases which were followed during two years. The thirteen new lung cancer cases diagnosed during the follow up time period clustered, based on liquid chromatography-mass spectrometry (LC-MS) data, with lung cancer cases at the time of BAL collection. Hundred and thirty-tree potential biomarkers were identified showing significantly differential expression when comparing lung cancer versus non-lung cancer. The regulated biomarkers showed a large overlap with biomarkers detected in tissue samples.

Bilateral Recurrent Spontaneous Pneumothorax as a Late Consequence of Oesophageal Surgery: Case Report.

INTRODUCTION: We report a case of a patient with recurrent bilateral spontaneous pneumothorax presumably originating in a left bulla. METHODS: A 68 year old male, was admitted to the emergency department with shortness of breath and bilateral chest pain. He had had oesophageal cancer resection 2 years before, with a posterior mediastinal reconstruction using a gastric tube. Afterwards he had to be operated twice for hiatal hernia. RESULTS: Bilateral chest tubes were inserted, with complete resolution in 72 hours. He was readmitted 20 days later, with a bilateral recurrence. A pneumologist was called upon. The thoracic CT scan revealed large bulla in the left upper lobe. There was no evidence of pneumomediastinum or mediastinal fluid collections. Communication between the two pleura was suspected. After discussion with the surgeon responsible for the previous interventions only the left chest was drained with bilateral lung expansion after suction. A left VATS approach revealed a partially adherent left lung, in its mediastinal face. Inflated bulla could be partially observed firmly glued to the upper mediastinum. A leak could not be demonstrated within the left thorax. Due to the firm adhesions of a presumably nonruptured bula to the phrenic nerve, a decision was made not to dissect it. A pleurectomy was performed. In the 3 days that followed, the fistula persisted and increased, in spite of lung expansion. A left thoracotomy was then performed. The full extent of the anterior mediastinal face of then left lung was dissected by opening the bulla that were partially left on the mediastinal pleura. Resection was made using tristaple endoGIA staplers ®. The posterior mediastinum was manually dissected free up to the presumed gastric tube location. At the end of surgery, no major air leaks were documented. Communication with the right pleura could not be located, not even with the aid of a 30o camera, but a large amount of fluid (1000cc) missing, was recovered after turning the patient. The postoperative period was prolonged ut to the 16th day, by a small but persistent air leak. CONCLUSION: Although no visual proof of communication between the two pleural cavities could be found, the control of the right pneumotorax by contralateral drainage, the resolution of the case by left pleurectomy and bulla resection backup this theory. This is an unique case, not previously reported, resolved by a multidisciplinary discussion of all the specialists involved in the treatment.

Unusual Behavior of a Lung Inflammatory Myofibroblastic Tumor: Case Report.

INTRODUCTION: 55 years old, male patient. History of heavy smoking (65 UMA) and COPD. Admitted to hospital due to a left pneumonia. Thoracic CT and PET-Scan, showed left lower lobe mass measuring 92x89 mm (SUVmax 49). Several mediastinal node groups presented increased uptake of FDG. A fiberoptic bronchoscopy was performed. Citology of the bronchoalveolar lavage suggested a squamous carcinoma. EBUS of node stations 4R, 4L e 7 without evidence of malignancy. METHODS: The case was taken to a multidisciplinary meeting staged as IIIA (T3N2M0). Neoadjuvant therapy (four cycles cysplatine and gemcitabine) was decided based on station 5, suspected disease. A left lower lobectomy was performed after a cervical mediastinoscopy excluded metastasis of node stations 4R and 4L. Histology of the specimen was compatible with inflammatory myofibroblastic tumor (IMT). No lymph node involvement was reported. It was restaged as IIB (ypT3N0M0). RESULTS: Three months after surgery one de novo nodule in the lingula with 12,7 of SUVmax was reported. The nodule was removed confirming a IMT metastasis. Four months after the nodule ressection a CT showed new lung and liver nodules. A total oclusion of the left main bronchus was documented and bronchoscopic debulking of the endobronchial mass again revealed IMT. Paliative radiotherapy was decided in the multidisciplinar group targeting the left main bronchus (five sessions of radiotherapy on a dose of 20Gy in 4Gy daily fractions). Ten months after surgery due to the onset of back pain, a CT revealed a sacrum lesion whose needle biopsy was suspicious for multiple myeloma. The patient was referred to another oncological center where previous non-surgical cases had been sent in the past. The patient is now proposed for histology reassessment and discussion by the hematology and pneumology medical teams. CONCLUSION: Inflammatory myofibrobastic tumors are considered benign or low-grade malignant tumors. The size of the tumour (cut-off of 3 cm) and secure surgical resection with free margins are the major determinants for recurrence and survival. There are some cases reported in the literature of distant metastasis and sarcomatous transformation after multiple recurrences. In our patient, the lesion was bigger than 3 cm and he underwent a complete resection. Nothing could foresee this aggressive metastatic behavior, especially when the recurrence did not show a sarcomatous transformation.