SALTT study: A retrospective analysis of 111 SAlivary gland tumors of Lung and Tracheobronchial Tree.

INTRODUCTION: Primary pulmonary salivary gland-type tumours (PPSGT) are rare lung neoplasms arising from submucosal seromucinous glands in the central airway. METHODS AND RESULTS: We retrospectively analysed the clinicopathological features of 111 PPSGTs diagnosed at our institute between 2003 and 2021. The mean age at diagnosis was 43.8 years(range 6-78 years) and a male-to-female ratio of 2:1. On imaging, 92 % of cases had centrally located tumours and 37.3 % were early stage. The histopathological types included 70 cases (63 %) of mucoepidermoid carcinoma (MEC), 31 cases (27.7 %) of adenoid cystic carcinoma (ADCC), two cases of myoepithelial carcinoma, one case each of acinic cell carcinoma (ACC), clear cell carcinoma (CCC), epithelial myoepithelial carcinoma (EMC) and 5 others [including adenocarcinoma of minor salivary gland origin(n = 3), carcinoma with sebaceous differentiation(n = 1) and poorly differentiated carcinoma of salivary gland type(n = 1)]. The size of the tumours found in the resection specimens ranged from 1 cm to 13 cm, with an average size of 4.9 cm. High-risk attributes such as lymphovascular invasion (LVI), perineural invasion (PNI), pleural involvement, positive resection margins, and nodal metastasis were identified in 15.3 %, 15.3 %, 13.6 %,15.2 % and 6.7 % of cases, respectively. These attributes were found to be more frequent in ADCC than in MEC. Surgery was the main treatment modality [68/84 (80 %) cases]. ADCC cases had more recurrence and distant metastasis than MEC cases. The 3- year overall-survival (OS) and recurrence-free survival(RFS) were better in patients with age lesser than 60 years(p-value <0.0001), low pT stage (p-value 0.00038) and lower grade of MEC(p-value-0.0067). CONCLUSION: It is crucial to have an acquaintance with the morphologic spectrum and immunophenotypic characteristics of PPSGT to recognize them in this unusual location. In tandem, it is crucial to differentiate them from conventional primary non-small cell lung carcinoma, as the management protocols and prognostic implications differ significantly.

[Features of surgical treatment of central tracheal and bronchial carcinoid]. / Osobennosti khirurgicheskogo lecheniya tsentral'nogo kartsinoida trakhei i bronkhov.

OBJECTIVE: To analyze features of surgical treatment of central tracheal and bronchial carcinoid. MATERIAL AND METHODS: A retrospective analysis included 115 patients with carcinoid tracheal and bronchial tumors who have been examined and treated from 1974 to the present. The majority of patients (97, 84.3%) had central form of carcinoid of the trachea, bronchi and lungs. Of these, 95 (97.9%) ones underwent surgical treatment. RESULTS: We used pre- and intraoperative diagnostics including bronchotomy. This approach provided organ-sparing surgery with resection and reconstruction of the bronchi and trachea in 71 (74.7%) patients including complete preservation of lung function in 20 (21.1%) cases and lobectomy/segmentectomy with resection and reconstruction of the bronchi in 51 (53.7%) cases. Two patients underwent pneumonectomy with wedge-shaped and marginal resection and reconstruction of tracheal bifurcation. Postoperative complications developed in 4 (4.2%) patients, and 2 (2.1%) ones died. Overall 5-year survival after radical surgeries was 89.2% (100% in typical carcinoid and 78.0% in atypical carcinoid).

[Isolated bronchoplastic procedure for typical carcinoid of the left lung]. / Izolirovannaya bronkhoplasticheskaya operatsiya mezhdolevoi shpory pri kartsinoide levogo legkogo.

Lung carcinoids (LC) comprise neuroendocrine lung tumors of low (typical carcinoid) and intermediate (atypical carcinoid) grade of malignancy accounting for less than 2% of all lung neoplasms. In Europe, annual incidence of LC varies from 0.2 to 2 per 100 000. This value increased dramatically over the past 30 years. One of the causes is improvement of diagnostic methods. Compared to aggressive high-grade neuroendocrine lung cancer, natural course of early-stage LC is usually indolent. Therefore, surgery with preservation of as much normal lung tissue as possible is preferable for resectable tumors. Nevertheless, the number of isolated bronchial resections with preservation of the entire lung tissue is relatively small, and these procedures remain technically complex interventions. We present isolated resection of interlobular spur, lower medial wall of distal part of the left main bronchus and proximal part of the lower lobular bronchus for typical carcinoid with monobronchial anastomosis and preservation of the entire lung parenchyma.

Prognosis of Patients with Bronchopulmonary Neuroendocrine Neoplasms in a Tertiary Neuroendocrine Tumor Centre of Excellence.

INTRODUCTION: The European Neuroendocrine Tumor Society (ENETS) reports variables of prognostic significance in bronchopulmonary neuroendocrine neoplasms (BP-NENs). The aim of this study was to investigate prognostic factors, recurrence-free survival (RFS), and overall survival (OS) for patients with typical carcinoid (TC), atypical carcinoid (AC), and large-cell neuroendocrine carcinoma (LCNEC). Current follow-up practices vary as the evidence is sparse, and we aimed to explore the relevance of routine bronchoscopy in follow-up. METHODS: This was a cohort study of 208 patients with BP-NENs followed at Aarhus University Hospital in 2008-2019. RFS and OS were determined using the Kaplan-Meier method for the variables such as primary tumor, primary treatment, smoking status, gender, and histological subtypes. RESULTS: The study included 153 patients with TC, 29 with AC, and 26 with LCNEC. Median follow-up was 48 months. The majority of patients (n = 191) received surgical resection, of which 22 (11%) recurred over time. Seventeen patients had nonsurgical treatment, of which 10 (59%) progressed. The 5-year OS rate was 86% for operated and 9% for nonoperated patients (p < 0.05). Patients with TC had a 5-year OS of 90% compared with 63% and 39% for AC and LCNEC, respectively. As for prognostic factors, nonsmokers did not secure a significant difference in OS compared with current/previous smokers (p = 0.51). In the follow-up period, only 2 (9%) of the 22 recurrences were found on a routine bronchoscopy. Both of these recurrences were also found by diagnostic imaging. CONCLUSIONS: Surgical treatment, especially, and diagnosis of TC were associated with a good prognosis. Furthermore, our data did not support routine bronchoscopy as part of a follow-up program for bronchial carcinoids.

Clinical and biological features of B-cell neoplasms with CDK6 translocations: an association with a subgroup of splenic marginal zone lymphomas displaying frequent CD5 expression, prolymphocytic cells, and TP53 abnormalities.

A translocation involving the cyclin-dependent kinase 6 (CDK6) gene [t(CDK6)] is a rare but recurrent abnormality in B-cell neoplasms. To further characterise this aberration, we studied 57 cases; the largest series reported to date. Fluorescence in situ hybridisation analysis confirmed the involvement of CDK6 in all cases, including t(2;7)(p11;q21) immunoglobulin kappa locus (IGK)/CDK6 (n = 51), t(7;14)(q21;q32) CDK6/immunoglobulin heavy locus (IGH) (n = 2) and the previously undescribed t(7;14)(q21;q11) CDK6/T-cell receptor alpha locus (TRA)/T-cell receptor delta locus (TRD) (n = 4). In total, 10 patients were diagnosed with chronic lymphocytic leukaemia, monoclonal B-cell lymphocytosis or small lymphocytic lymphoma, and 47 had small B-cell lymphoma (SmBL) including 36 cases of marginal zone lymphoma (MZL; 34 splenic MZLs, one nodal MZL and one bronchus-associated lymphoid tissue lymphoma). In all, 18 of the 26 cytologically reviewed cases of MZL (69%) had an atypical aspect with prolymphocytic cells. Among the 47 patients with MZL/SmBL, CD5 expression was found in 26 (55%) and the tumour protein p53 (TP53) deletion in 22 (47%). The TP53 gene was mutated in 10/30 (33%); the 7q deletion was detected in only one case, and no Notch receptor 2 (NOTCH2) mutations were found. Immunoglobulin heavy-chain variable-region (IGHV) locus sequencing revealed that none harboured an IGHV1-02*04 gene. Overall survival was 82% at 10 years and not influenced by TP53 aberration. Our present findings suggest that most t(CDK6)+ neoplasms correspond to a particular subgroup of indolent marginal zone B-cell lymphomas with distinctive features.

Benign tumours of the bronchopulmonary system.

The vast majority of tumours arising in the bronchopulmonary system are malignant in nature. Benign tumours of the lung are relatively rare and are often incidental findings during clinical investigations for unrelated conditions. These lesions can arise in the bronchial tree or the pulmonary parenchyma and may be of epithelial, mesenchymal, salivary gland-type or unknown differentiation. Although the spectrum of these lesions is wide, the clinical, pathological and immunohistochemical characteristics of the most relevant will be the subject of this review. In addition, the most important features allowing differentiation from malignant pulmonary neoplasms will be discussed.

Extra-appendicular neuroendocrine tumors: A report from the TREP project (2000-2020).

BACKGROUND: Extra-appendicular neuroendocrine tumors (NETs) are very rare tumors. While diagnostic and therapeutic guidelines are well established for adults, data on children and adolescents are lacking. PATIENTS AND METHODS: Patients with a diagnosis of extra-appendicular NET registered on the Tumori Rari in Età Pediatrica - Rare Tumors in Pediatric Age (TREP) from 2000 to 2020 were analyzed. Clinical characteristics including patients' presentation, tumor features, treatment, and outcome were reviewed. RESULTS: Twenty-seven patients with extra-appendicular NET registered on TREP with a median age of 173 months. The primary site was the pancreas (12) or bronchi (10) in the majority of cases. Other primary sites included the thymus, Meckel's diverticulum, and liver. Thirteen (48%) of tumors extended beyond the organ of origin: four invaded neighboring organs and/or regional nodes and nine involved distant metastases. The 3-year event-free survival (EFS) for those with localized disease was superior to those with metastatic disease (66.6% 95% CI 5-95% vs 33% 95% CI 5-68%, respectively; P = .005). A complete resection was feasible in 17 patients. The 3-year EFS in these patients was superior to those with no or incomplete resection (R0 vs R1/R2, respectively; P = .007). Overall, 16 children had no evidence of disease at follow-up, and one is alive with disease; five died, and five were lost to follow-up. CONCLUSIONS: Data from our experience demonstrated a wide heterogeneity of presentation and outcome of these tumors. Localized disease and complete surgical resection were the main prognostic factors of good outcome. Other therapies may have a role in prolonging survival in metastatic disease.

The Role of Rigid Bronchoscopic Intervention for Bronchial Carcinoid.

Bronchial carcinoid is a rare malignant tumor that is categorized as a typical carcinoid or atypical carcinoid. Many institutions use flexible bronchoscopy for diagnosis. However, due to the hemorrhagic nature of the tumor, the amount of specimen obtained is often small, making it difficult to obtain an accurate diagnosis. The use of rigid bronchoscopy may not only contribute to obtaining a diagnosis but also be beneficial in the treatment plan. The aim of this study was to evaluate the efficacy of rigid bronchoscopic interventions for the diagnosis and treatment of bronchial carcinoids. All patients with bronchial carcinoids who underwent rigid bronchoscopic intervention under general anesthesia at our institution between June 2006 and August 2018 were analyzed retrospectively. Eight patients [3 men and 5 women; median age, 71 years (range 45-82 years)] were eligible for the analysis. None of the cases had accurate subtyping preoperatively before intervention. In contrast, all cases were diagnosed as carcinoid with subtypes (5 patients had typical carcinoid and 3 had atypical carcinoid) following rigid bronchoscopic intervention. All respiratory symptoms improved immediately after the procedure. One instance of bleeding occurred, and was easily controlled by argon plasma coagulation and intraluminal administration of epinephrine under flexible and rigid bronchoscopy. Four patients (3 with typical carcinoid and 1 with atypical carcinoid) underwent radical surgery sequentially, and no recurrences were observed. We conclude that rigid bronchoscopic intervention is safe and effective for accurate diagnosis and improvement of respiratory symptoms in patients with bronchial carcinoids.

[A case of bronchial mucous gland adenoma: A rare diagnosis that should not be mistaken!] / Un cas d'adénome muqueux glandulaire bronchique : un diagnostic rare à ne pas méconnaître !

We report the case of a 32-year-old man, who was admitted for a recurrent pneumopathy. The thoracic computed tomography revealed a small well-circumscribed lesion of the lower right lobe of the lung. Microscopic examination from the biopsy material of the endoscopy concluded a mucoepidermoid carcinoma. A lobectomy was realized. Microscopic examination revealed the presence of a well-delineated lesion composed of glands and cysts containing mucous and limited by mucous and cylindric and ciliated cells without atypia. The proliferation index was very low. A diagnosis of mucous gland adenoma was made. It is an exceptional tumor and is very difficult to diagnose on biopsy material but should be known by pathologists. It is associated with a good prognosis. The aims of our observation are to present the macroscopic and microscopic features of this tumor and data from recent literature review to better diagnose it. This is also the second observation with molecular details for this entity.

Airway Foreign Body Mimicking an Endobronchial Tumor Presenting with Pneumothorax in an Adult: A Case Report.

Foreign body (FB) aspiration occurs less frequently in adults than in children. Among the complications related to FB aspiration, pneumothorax is rarely reported in adults. Although the majority of FB aspiration cases can be diagnosed easily and accurately by using radiographs and bronchoscopy, some patients are misdiagnosed with endobronchial tumors. We describe a case of airway FB that mimicked an endobronchial tumor presenting with pneumothorax in an adult. A 77-year-old man was referred to our hospital due to pneumothorax and atelectasis of the right upper lobe caused by an endobronchial nodule. A chest tube was immediately inserted to decompress the pneumothorax. Chest computed tomography with contrast revealed an endobronchial nodule that was seen as contrast-enhanced. Flexible bronchoscopy was performed to biopsy the nodule. The bronchoscopy showed a yellow spherical nodule in the right upper lobar bronchus. Rat tooth forceps were used, because the lesion was too slippery to grasp with ellipsoid cup biopsy forceps. The whole nodule was extracted and was confirmed to be a FB, which was determined to be a green pea vegetable. After the procedure, the chest tube was removed, and the patient was discharged without any complications. This case highlights the importance of suspecting a FB as a cause of pneumothorax and presents the possibility of misdiagnosing an aspirated FB as an endobronchial tumor and selecting the appropriate instrument for removing an endobronchial FB.

[Surgery for carcinoid tumor of lungs, bronchi and trachea]. / Khirurgiya kartsinoidnoi opukholi legkikh, bronkhov i trakhei.

OBJECTIVE: To analyze the long-term outcomes of local resections in patients with carcinoid tumors of bronchopulmonary system. MATERIAL AND METHODS: There were 52 patients with tracheal and bronchopulmonary carcinoid for the period 2013-2019. The sample included 21 men and 31 women. Age of patients ranged from 20 to 82 years (mean 62 years). Typical carcinoid was diagnosed in 34 cases, atypical carcinoid - in 18 cases. Central tumor was diagnosed in 26 patients. Tracheal neoplasm was found in 2 patients. Another patient had mediastinal tumor. Five patients underwent resection with broncho- or tracheobronchoplastic reconstruction. RESULTS: Surgical approach for carcinoid is determined by its differentiation, localization and lung tissue lesion following a long-standing tumor. These operations are quite safe. Complications occurred after 4 (7.7%) surgeries. Long-term results were followed-up for the period from 8 months to 7 years. There were no signs of recurrence and disease progression after organ-sparing bronchial resection. Local resection with bronchoplasty is advisable for typical carcinoid.

[Bronchial Mucoepidermoid Carcinoma in Children and Its Misdiagnosis:Report of One Case].

Bronchial mucoepidermoid carcinoma is a rare malignancy with varied disease courses.The symptoms are non-specific and mostly related to infection and airway obstruction secondary to the tumor.Bronchial mucoepidermoid carcinoma is difficult to be distinguished from pneumonia,tracheobronchitis,chronicobstructive pulmonary disease,asthma,and other respiratory diseases in its early stage.The age of onset is mostly between 20 and 55 years,and the disease is rarely seen in children.Confirmation of bronchial mucoepidermoid carcinoma depends on bronchoscopy and pathological biopsy,and this disease is often missed and misdiagnoed.

Analysis of the Clinical Features of Tracheobronchial Fungal Infections with Tumor-Like Lesions.

BACKGROUND: Tracheobronchial fungal infections (TBFI) cause life-threatening complications in immunocompromised hosts but are rarely reported. Misdiagnosis and delayed antifungal treatment are associated with the high mortality rate of patients with TBFI. OBJECTIVES: This study analyzed the bronchoscopic features of TBFI and their roles in the early diagnosis of TBFI. METHODS: The demographic, clinical, radiologic, and bronchoscopic data of 53 patients diagnosed with TBFI in our department during a 15-year period were retrospectively analyzed. RESULTS: Most of the TBFI patients were male, and mass was the most common radiologic abnormality. Obvious predilection in primary bronchus distributions was observed. 41.9% of the 43 Aspergillus tracheobronchitis (AT) patients, 70% of the 10 tracheobronchial mucormycosis (TM) patients, and 100% of the 3 endobronchial cryptococcosis patients had been misdiagnosed as having cancer on bronchoscopy because of the presence of tumor-like lesions. The most common features of AT were bronchial occlusion with a mass or mucosal necrosis, bronchial stenosis with mucosal hyperplasia, or uneven mucosa. The main descriptions of TM were bronchial stenosis or obstruction due to mucosal necrosis, uneven mucosa, or a mass. The endoscopic characteristics of endobronchial cryptococcosis included occlusion due to uneven mucosa or mass, or external compressive stricture. CONCLUSION: Immunocompromised patients and immunocompetent patients with underlying disease displaying tumor-like lesions on bronchoscopy should be differentially diagnosed with cancer. Bronchial biopsy is indispensable for the early diagnosis of TBFI.

Bronchial angiolipoma successfully treated by sleeve resection of the right bronchus intermedius: a case report.

BACKGROUND: Angiolipoma is a rare, benign tumor that primarily develops in the limbs and trunk. The occurrence of angiolipoma in the lungs is extremely rare; to date, only two cases of primary bronchial angiolipoma have been reported. Here, we report a case of angiolipoma of the right bronchus intermedius that was successfully treated with sleeve resection and reconstructive surgery. CASE PRESENTATION: This report presents a case of angiolipoma that developed in the right bronchus intermedius of a 68-year-old man. A chest CT revealed a 10-mm endobronchial mass that was clearly visible as a high-attenuation area of contrast enhancement. Bronchoscopy revealed a submucosal tumor on the anterior wall of the entrance to the right bronchus intermedius that was constricting the airway lumen. The tumor surface was covered with numerous engorged blood vessels, and the middle and inferior pulmonary lobes were intact. Bronchial sleeve resection of the right bronchus intermedius was performed. Histologically, a mixture of proliferating blood vessels and adipocytes were observed within the bronchus wall. Therefore, the pathological diagnosis was angiolipoma. Lung function was preserved, and complete resection of the tumor was achieved. At present (2 years and 7 months after surgery), the patient is recurrence-free. CONCLUSION: Accordingly, using bronchial sleeve resection and end-to-end anastomosis techniques, we accomplished complete tumor excision and avoided the need to resect additional lung parenchyma. Our procedure preserved pulmonary function and yielded a curative result. Bronchoscopic intervention or minimal parenchymal resection should be considered as treatments for bronchial angiolipoma. Given the small number of reports of bronchial angiolipoma, the collection of additional data is important to elucidate the clinical characteristics of this rare tumor.

[Bronchial Typical Carcinoid Tumor Treated with Two-stage Resection;Report of a Case].

A 45-year-old woman, who had been treated for bronchial asthma, was referred to our hospital with symptoms of dyspnea. Upon examination, we found the right main bronchus to be almost completely occluded by an endobronchial tumor. For the purpose of diagnosis and relieving the dyspnea, we performed a rigid bronchoscopic tumor resection with a high frequency snare. The tumor was pathologically diagnosed as a typical bronchial carcinoid, and a right upper lobectomy and wedge resection of the right main bronchus was carried out 1 month later.

Histologically Proven Bronchial Neuroendocrine Tumors in MEN1: A GTE 51-Case Cohort Study.

OBJECTIVE: To evaluate the natural history of MEN1-related bronchial endocrine tumors (br-NETs) and to determine their histological characteristics, survival and causes of death. br-NETs frequency ranges from 3 to 13% and may reach 32% depending on the number of patients evaluated and on the criteria required for diagnosis. METHODS: The 1023-patient series of symptomatic MEN1 patients followed up in a median of 48.7 [35.5-59.6] years by the Groupe d'étude des Tumeurs Endocrines was analyzed using time-to-event techniques. RESULTS: br-NETs were found in 51 patients (4.8%, [95% CI 3.6-6.2%]) and were discovered by imaging in 86% of cases (CT scan, Octreoscan, Chest X-ray, MRI). Median age at diagnosis was 45 years [28-66]. Histological examination showed 27 (53%) typical carcinoids (TC), 16 (31%) atypical carcinoids (AC), 2 (4%) large cell neuroendocrine carcinomas (LCNEC), 3(6%) small cell neuroendocrine carcinomas (SCLC), 3(6%) TC associated with AC. Overall survival was not different from the rest of the cohort (HR 0.29, [95% CI 0.02-5.14]). AC tended to have a worse prognosis than TC (p = 0.08). Seven deaths were directly related to br-NETs (three AC, three SCLC and one LCNEC). Patients who underwent surgery survived longer (p = 10-4) and were metastasis free, while 8 of 14 non-operated patients were metastatic. There were no operative deaths. CONCLUSIONS: Around 5% of MEN1 patients develop br-NETs. br-NETs do not decrease overall survival in MEN1 patients, but poorly differentiated and aggressive br-NETs can cause death. br-NETs must be screened carefully. A biopsy is essential to operate on patients in time.

Colon carcinoma with endobronchial metastasis masquerading as bronchial asthma causing ball valve effect.

Malignant central airway obstruction (CAO) with ball valve effect (BVE) in the lung is rare. We discuss a case of metastatic colon cancer who presented with asthma like symptoms which thoracic computed tomography and bronchoscopy revealed an intraluminal tumour obstructing the left main bronchus in a ball valve manner. Airway patency was restored urgently with immediate alleviation of symptoms. This illustrates the importance of recognizing subtle features of central airway obstruction to allow expedition of appropriate investigations and therapy.

Autofluorescence and White Light Bronchoscopy in the Diagnosis of Endobronchial Malignant Lesions.

BACKGROUND: Autofluorescence bronchoscopy (AFB) allows a more sensitive approach to the diagnosis of premalignant and malignant endobronchial lesions than white light bronchoscopy (WLB) can do. AIM: To assess the autofluorescence bronchoscopy and white light bronchoscopy in diagnosing malignant endobronchial lesions. MATERIALS AND METHODS: The design of the study is a retrospective case-control study. Thirty-two parameters were entered into an Excel file and analysed with SPSS v. 21 for Mac book Pro. Endoscopy findings were graded in 4 options and morphological results - in 9 options according to WHO classification. The results are presented using McNemar's test and sensitivity, specificity and positive and negative predictive values as well. RESULTS: Three hundred and three patients were included in the study. Lung cancer was found in 38.3% of the patients using histology and in 35.6% - using cytology. McNemar's test for AFB finding for suspected and malignant lesions OR was 8.333 (95% CI 3.571-23.784) while for WLB OR was 0.128 (95% CI 0.045-0.299). For cytological results OR was 3.800 (95% CI 2.123-7.227) and 3.471 (95% CI 1.996-6.351), respectively. P value was <0.0001 for all tests. Sensitivity for AFB and WLB was 94.83% but specificity was 52.83% and 55.66% if histology was used. For cytology these numbers were respectively 86.11% and 84.26% for sensitivity, and 63.69% and 62.42% for specificity. CONCLUSION: AFB has an advantage over WLB in diagnosing endobronchial malignant lesions. Biopsying suspicious, not only visible malignant lesions, increased diagnostic sensitivity.

How many samples would be optimal for endobronchial cryobiopsy?

BACKGROUND: Cryobiopsy, which provides larger specimens without crush artifact, is a good option for the diagnosis of visible endobronchial tumors. While there are several papers on diagnostic performance, application protocols vary between centers. In this study, we aimed to find the optimal number of cryobiopsies in endobronchial tumors. METHODS: We prospectively involved cases with a visible endobronchial tumor in which conventional diagnostic measures failed and/or a therapeutic interventional bronchoscopy was planned. Endobronchial tumor was visualized, and four cryobiopsies were taken with a dedicated flexible probe. The samples were evaluated by a pathologist who was blinded to the order of the biopsies. The cumulative performances of one to four cryobiopsies were compared, and a complication analysis was conducted. RESULTS: A total of 50 patients were involved. Four cryobiopsies were taken from 49 patients, and a single biopsy was taken from one case. The sensitivities of one, two, three and four biopsies were 82, 93.9, 93.9 and 95.9 %, respectively. The difference in performance of one and two biopsies was significant (p = 0.031), but the third and fourth biopsies were found to be unnecessary (p = 1.0 for second versus third and p = 1.0 for second versus fourth). Bleeding risk increased when ≥3 cryobiopsies were taken (Odds Ratio 2.758). CONCLUSIONS: When the diagnostic benefits and complication rates were considered, two cryobiopsies were found to be optimal for endobronchial tumors. In patients with non-diagnostic conventional bronchoscopy, endobronchial tumors may be diagnosed by cryobiopsy.