Table 2. Baseline patient characteristics .
IQR: Interquartile range
SD: Standard deviation
MRC: Medical Research Council
MMRC: Modified Medical Research Council
| Authors | Study design | Year | Age in years | Total number of patients (n. number of patients) (male/female) | Type of cancer (n, number of patients)/stage | Clinical presentation (n, number of patients)/characteristics of patients included in the study | Smoking status (n, number of patients) | Comorbid conditions | |
| 1. | Dalar L et al [8]. | Retrospective cohort study | 2016 | Median age 63 | 547 (432/115) | Squamous cell cancer, Small cell cancer (53), Adenocarcinoma (31), Non-small cell cancer (181), Carcinoid tumor (9), Thyroid cancer (4), Renal cell cancer (4), Malignant Mesothelioma (2), Neuroendocrine tumor (9), Malignant Mesenchymal tumor (9), other metastasis (17). | Not mentioned | Smoker (446), Nonsmoker (101) | Not mentioned |
| 2. | Dutau H et al [9]. | Prospective clinical trial | 2020 | Mean age (Mean ± SD) 64.5 ± 10.6 years. | 78 (64/14) | Squamous cell carcinoma was the main histology (45 patients). | Patients with mechanical airway obstruction due to Non-small cell lung cancer, undergoing therapeutic bronchoscopy were included, if at the end of the procedure they fulfilled following criteria for stent placement. (1) Airway lumen > 50%; (2) Absence of extrinsic compression requiring stenting; (3) Residual tumor that could entirely be covered with one straight or Y silicone stent (Tracheobronxane, Novatech) from the proximal to the distal margin. | Not mentioned | Not mentioned |
| 3. | Grosu HB et al [10]. | Retrospective cohort study | 2013 | Mean age (Mean ± SD) 59.4 ± 13.7. | 72 (45/27) | Non-small cell lung cancer (32), Renal cell (10), Sarcoma (6), Colon (4), Thyroid (4), Melanoma (3), Breast (2), Head and neck (1), Small cell (1), Lymphoma (1), Other solid tumors metastatic to lung (8). | For patients with malignant central airway obstruction, stents were placed if there was pure extrinsic compression with 50% airway occlusion, or adequate airway patency (50%) could not be achieved with ablative techniques alone, or if it was felt that airway re-occlusion would occur quickly if a stent was not placed following ablation for a mixed obstruction. | Smokers: 5 active, 44 ex- smokers Nonsmokers: 23 | Not mentioned |
| 4. | Huang S et al [11]. | Retrospective cohort study | 2017 | Number of patients less than 50 years of age: 3. Number of patients more than 50 years of age: 53. | 45/11/56 | Lung cancer (29), Esophageal cancer (27) Pathology: Others and unknown: 17, Squamous carcinoma 35, Adenocarcinoma 4. | Dyspnea, Airway Neoplasm, Extrinsic compression, Fistula. | Smokers: 24 Non-smokers: 23 | Not mentioned |
| 5. | Iyoda A et al [12]. | Retrospective chart review | 2021 | Mean age 64, Mean age in the silicone stent (SS) group: 62 years, mean age in the metallic stent (MS) group: 65 years. | 106 (80/26) SS: 33/12, MS: 47/14) | Lung cancer (52) (SS: 23 and MS: 29), Esophageal cancer (39) (SS: 14 and MS: 25), Other (15) (SS: 8 and MS: 7). Primary cancer 77 (SS: 33, MS: 44) Recurrent cancer 27 (SS: 11, MS: 16). | 106 patients with central airway stenosis or obstruction due to thoracic malignancy who underwent first placement of either SS or MS at Toho University Omori Medical Center between 1998 and 2018. | Not mentioned | Not mentioned |
| 6. | Lachkara S et al [13]. | Retrospective chart review | 2020 | Mean age (Range) with range: Silicone Y stent (SYS): 60.6 (38-85) SEM Y stent (SEMYS: 57.7 (37-78). | SYS: 25/15 SEMYS: 28/10 | SYS: Lung cancer (25), Esophageal cancer (11), Other (3), NA (1) SEMYS: Lung cancer (22), Esophageal cancer (14). | Patients with malignant carina involvement (stenosis or tracheobronchial esophageal fistula), not suitable for curative surgery, and treated with bronchial Y stent, were selected for the present study. | Not mentioned | The main indication for stenting was tracheobronchial obstruction in 61 patients, including 20 compressions (7 in the SEM Y group, 13 in the SYS group), association of tracheoesophageal fistula and obstruction in 4 patients (2 in SEM Y group), and fistula without obstruction in 13 (10 in the SEM Y group). Of the 78 patients, 25 had esophageal cancer (14 in the SEM Y group), 47 had primary lung cancer (22 in the SEM Y group), and 6 had extra thoracic primary cancer (2 in the SEM Y group). |
| 7. | Ma G et al [14]. | Retrospective chart review | 2008 | Median age (IQR) 57, (37-75) | 52 (32/20) | 30 cases caused by Lung cancer; 13 cases by Esophageal carcinoma, six cases by Lymphoma and three cases with unknown pathology. | Large airway stenosis with severe respiratory difficulties caused by malignant tumor compression or invasion. | Not mentioned | Not mentioned |
| 8. | Marchese R et al [15]. | Retrospective chart review | 2015 | Mean age (Mean ± SD) 64±11 | 51 (37/14) | Lung cancer (44) of which: Non-small cell lung cancer (18), Squamous cell cancer (19), Small cell lung cancer (7). Metastasis (5): Colon cancer (1) Esophageal cancer (1) Endometrial cancer (2) laryngeal cancer. Hemangiopericytoma (1). | All patients were symptomatic; most of them complained of dyspnea (29) of moderate degree [modified MRC (Mean ± SD) 2.6 ± 0.8} and cough (25). | Not mentioned | Not mentioned |
| 9. | Marchese R et al [16]. | Retrospective chart review | 2020 | Mean age 67, range 45–85 years. | 51 (41/10) | 51 patients affected by advanced unresectable lung cancer involving lobar bronchi and distal carina (RC1, RC2, or LC2). | Symptoms: Dyspnea (27), MMRC (Mean: 2.4 ± 0.7), Cough (22), Hemoptysis (7), Chest pain (5). | Smokers: (before stenting/ after stenting) (28/12) Ex-smoker (15/31) Never smoke (8/8). | Not mentioned |
| 10. | Marchioni A et al [17]. | Multicentric retrospective study | 2020 | Age (IQR): For the complete study, 74 (68-79.3). For the integrated treatment, 73.3 (66.3-78.4). For the standard treatment: 76 (71-80.5). | Total number of patients, 100. Integrated treatment, 60 patients. Standard treatment, 40 patients. Male (68). 37 in the integrated treatment group, 31 in the standard treatment group. | NSCLC/Stage IIIB | Central airway obstruction | Not mentioned | Not mentioned |
| 11. | Miyazawa T et al [18]. | Prospective multicenter study | 2000 | Mean: 63.0, range: 41–82 years | 34(30/4) | Bronchogenic carcinoma Squamous cell carcinoma 11 Adenocarcinoma 8 Small cell carcinoma 5 Adenoid cystic carcinoma 1 Esophageal carcinoma 4 Mediastinal tumor 3 Metastatic pulmonary disease 2. | Not mentioned | Not mentioned | Not mentioned |
| 12. | Miyazawa T et al [19]. | Prospective case control | 2004 | Mean ± SD. Tracheal stenosis: 61.2 ± 5.9. Carinal stenosis: 64.9 ± 5.6. Bronchial stenosis: 67.7 ± 5.5. Extensive stenosis: 66.4 ± 3.0. | Tracheal stenosis: 20 (18/2) Carinal stenosis: 16 (11/5) Bronchial stenosis: 18(14/4) Extensive stenosis: 10 (7/3) | 38 patients with adenocarcinoma, 18 with squamous cell carcinoma, and 8 with recurrence of small cell carcinoma after chemotherapy and/or radiotherapy/stage IIIB/IV. | Patients with World Health Organization Dyspnea Grade III–IV, stage IIIB/IV inoperable lung cancer without further treatment options, central airway stenosis due to extrinsic compression, and residual stenosis of more than 50% after balloon dilatation. | Not mentioned | Not mentioned |
| 13. | Monnier P et al [20]. | Prospective Trial | 1996 | Average age was 62 years (range, 36 to 83 years). | 40 (29/11) | Primary tracheal or bronchial squamous cell carcinoma in 25 cases (in 3 cases there was tumoral recurrence of anaplastic small cell carcinoma after chemotherapy). 3 cases presented with esophageal squamous cell carcinoma and a tracheobronchial fistula, and other histologic features were present in 9 cases. | Severely debilitated, presenting with dyspnea and/or pulmonary or lobar atelectasis. Most of them had already undergone one or more treatments: Radiotherapy (15), pulmonary resections (11), palliative laser dilatation (10), chemotherapy (7), insertion of another stent (4). | Not mentioned | Not mentioned |
| 14. | Nakajima Y et al [21]. | Retrospective review | 1999 | Mean 62 years, range 52 to 83 years | 22 patients (18 men, 4 women). | Bronchogenic carcinoma (14), Esophageal carcinoma (7) and Thyroid carcinoma (1). The causes of airway stenosis were extrinsic compression by mediastinal adenopathy in 17 patients and intrinsic mucosal lesions of bronchogenic carcinoma in five. | Not mentioned | Not mentioned | Not mentioned |
| 15. | Oki M et al [22]. | Retrospective chart review | 2017 | Median age (IQR) 62.5 years (13–86) | 30 (24/4) | Lung cancer (17), Squamous cell carcinoma (10), Adenocarcinoma (6), Small cell carcinoma (1), Esophageal cancer (6), Thyroid cancer (2), Renal cell carcinoma (1), Adenoid cystic carcinoma (1), Malignant lymphoma (1), Tracheal cancer, Squamous cell carcinoma (1), Ewing sarcoma (1). | Patients with malignant airway stenosis requiring emergency intubation prior to stenting procedures. | Not mentioned | Not mentioned |
| 16. | Özdemir C et al [23]. | Retrospective chart review | 2016 | Mean ± SD, 58.14 ± 8.48 years. Range 44–72 years. | 14 (12/2) | Non-small cell lung cancer (11), Small cell lung cancer (1). | Patients inducted into the study if airway patency was <50 % after rigid bronchoscopy intervention (dilatation and/or de-obstruction), or if the recurrence risk was high. Another indication for stent application was to cover fistula when a fistula stoma was detected by bronchoscopy evaluation in between central airway and esophagus or mediastinum. | Not mentioned | Not mentioned |
| 17. | Razi SS et al [24]. | Retrospective chart review | 2010 | Mean ± SD, 66 ± 13 years. Range, 44–89 years. | 50 (29/21) | Non-small cell lung cancer (38), Small cell lung cancer (4), Esophageal cancer (4), Mediastinal sarcoma (2), and Metastatic colon and breast cancer (2). Nine patients had stage IIIa/b disease while 41 patients had stage IV disease at the time of initial airway intervention. | Symptomatic malignant central airway obstruction who underwent airway stenting with or without endoscopic tumor resection. Dyspnea (46), Cough (24), Chest pain (11), Hemoptysis (11) Miscellaneous (25). | Smokers (13) Past smoker (32) Never smoker (5) | Not mentioned |
| 18. | Righini C et al [25]. | Retrospective chart review | 2010 | Mean age (Mean ± SD) 61.7±14.0 | 69 (40/29) | Tracheobronchial cancers (32), Esophageal cancer (19), Thyroid cancer (9), Mediastinal malignancy (6), Other malignancies (3. 1 of each: Pulmonary sarcoma, Distant metastasis from Malignant melanoma, and Endometrial carcinoma). | Patients recorded in our hospital pharmacy order database as having an airway stent insertion for malignant airway obstruction were reviewed. | Not mentioned | Not mentioned |
| 19. | Saji H et al [26]. | Retrospective chart review | 2010 | Range from 42 to 91 years with a mean age of 63.9 years | 59 (51/8) | Squamous cell carcinoma (30), Adenocarcinoma (20), Large cell carcinoma (4), Small cell carcinoma (3), unclassified carcinoma (2). | Not mentioned | Not mentioned | Not mentioned |
| 20. | Tayama K et al [27]. | Retrospective chart review | 1997 | Range 37 to 77 years (Mean age 59 years) | 20 (08/12) | Esophageal carcinoma (11), Primary lung carcinoma (3), Malignant lymphoma (1), Metastatic lung carcinoma (1), Thyroid carcinoma (1), Adenoid cystic carcinoma (1), Recurrent lung carcinoma (1), Recurrent thyroid carcinoma (1). | Malignant airway obstruction | Not mentioned | Not mentioned |
| 21. | Verma A et al [28]. | Retrospective review | 2018 | Median (range). Total, 63 (23-86). Laser group, 63 (23-86). Ultraflex stent, 63 942-86). | 30 (22/8) | Squamous cell carcinoma (5), Local extension: Lung cancer (12), Esophageal cancer (10) Anaplastic thyroid carcinoma (2), LELC (lymphoepithelial carcinoma) (1), Sarcomatoid tumor (1), Neuroendocrine cancer (1), Unidentified (1). | Malignant airway obstruction | Not mentioned | Not mentioned |
| 22. | Wilson GE et al [29]. | Retrospective chart review | 1996 | Mean age 64 years (range 30-82). | 56(33/23) | Primary tumor type (47), Squamous cell carcinoma (25), Non-small cell cancer (3), Small cell cancer (6), Adenocarcinoma (4), Adeno-squamous carcinoma (1), Presumed carcinoma (9) Secondary tumor (9) Esophageal cancer (3), Breast cancer (2), Thyroid cancer (2), Melanoma (1), Colon cancer (1). | Respiratory distress due to malignant obstruction of the trachea and/or a main bronchus. | Not mentioned | Not mentioned |
| 23. | Yerushalmi R et al [30]. | Retrospective chart review | 2006 | Range 36 to 85 years (median 68). | 34 | Thirty-five percent of the patients had primary lung cancer and 65% had metastatic disease. | Dyspnea (82%), cough (11.7%), hemoptysis (9%), pneumonia (5.9%), and atelectasis (3%). | Not mentioned | Not mentioned |
| 24. | Zwischenberger JB et al [31]. | Retrospective chart review | 1997 | Range 38 to 76 years (Mean age 58 years). | 14(07/07) | Poorly differentiated non-small cell cancer (6), Adenocarcinoma (2), Squamous cell carcinoma (4), Large cell cancer (1), Small cell cancer (1). | Severe dyspnea (American Thoracic Society grade 4). | Not mentioned | Not mentioned |
| 25. | Akram MJ et al [32]. | Retrospective cross-sectional review | 2020 | Mean age 46.63 ± 16.02. | 51 (24/27) | Esophageal cancer (37), Lung cancer (6), Osteosarcoma (2), Hodgkins’s disease (1), Breast carcinoma (1), Rectal carcinoma (1), Mixed germ cell tumor (1), Sarcomatoid mediastinal cancer (1), Thyroid cancer (1). | Poor performance status (96.1%), shortness of breath (39.2%), fever with productive cough (23.5%) and stridor with shortness of breath (21.6%). | Not mentioned | Not mentioned |
| 26. | Bolliger CT et al [33]. | Prospective study | 2004 | Mean age 62 years (range: 37–83) | 26 (16/10) | Bronchogenic carcinoma (18), Esophageal carcinoma (4), Metastases (2), Tracheal carcinoma (1), Schwannoma (1). | Dyspnea, infection, cough, hemoptysis. | Not mentioned | Not mentioned |
| 27. | Chhajed PN et al [34]. | Retrospective Study | 2010 | Median, 63 years | Patients in which stents were placed: 93 out of total 130 (88/42) | Values given as in number of procedures (total procedures were 167) in 130 patients as total: Lung cancer: (103), Esophageal cancer (9), pulmonary metastases (55). | Not mentioned | Not mentioned | Not mentioned |