The impact of early surgical treatment of tracheal stenosis on neurorehabilitation outcome in patients with severe acquired brain injury.

INTRODUCTION: Acquired tracheal stenosis (TS) is a potentially life-threatening condition following prolonged intubation and/or tracheostomy in adult patients with severe Acquired Brain Injury (sABI), requiring a tracheal resection and reconstruction. METHODS: We included 38 sABI adult patients with TS, admitted at a post-acute Neurorehabilitation Hospital. Disability Rating Scale (DRS) and other functional assessment measures were recorded at admission (t1), before TS surgical treatment (t2), and at discharge (t3). Patients were defined as 'improved' when they changed from a more severe to a less severe disability, between time t2 and time t3, and as "not improved" when they did not show any further improvement between t2 and t3, or they already exhibited a disability improvement since time interval t1-t2. RESULTS: Time interval between the injury onset and TS surgical treatment (t2-t0) was associated with the patient's disability improvement, suggesting the t2-t0 time interval ≤ 115 days as a cutoff value for a possible functional recovery. A t2-t0 time interval ≤ 170 days is also associated to absence of persistent dysphagia. CONCLUSIONS: Early TS surgical treatment within 115 days from the injury onset contributes to the improvement of the disability level in patients with sABI, optimizing their functional outcomes and recovery potential.

Efficacy of Extracorporeal Photopheresis in Patients With Bronchiolitis Obliterans Syndrome After Lung Transplantation.

BACKGROUND: Lung transplantation (LT) is only therapeutic option for patients affected by chronic respiratory failure. Chronic rejection, also known as bronchiolitis obliterans syndrome (BOS), is still the main cause of death and the most important factor that influences post-transplantation quality of life. Currently available therapies have not been proven to result in significant benefit in the prevention or treatment of BOS. Extracorporeal photopheresis (ECP) seems to reduce the rate of lung function decline in transplant recipients with progressive BOS. METHODS: From 1991 until now, 239 LTs were performed at our center. Fifty-four patients (22.5%) developed BOS; 15 of these (27.7%) were treated with ECP. At the beginning of the treatment, all patients showed a mean decline of forced expiratory volume in 1 second (FEV1) from baseline values of 45.8% ± 17.2%; 2 patients were in long-term oxygen therapy. RESULTS: Mean follow-up from November 2013 to June 2016 was 11.6 ± 7 months. Twelve patients (80%) showed lung function stabilization with an FEV1 range after treatment between -6% to +8% from the pre-treatment values. We did not report any adverse effects or increase of infections incidence. DISCUSSION: ECP seems to be an effective and well-tolerated therapeutic option for LT patients with BOS in terms of stabilization of lung function and increased survival.

Evaluation of Renal Function in Patients Undergoing Lung Transplantation.

BACKGROUND: Acute kidney injury and chronic kidney failure are serious complications after lung transplantation. Glomerular filtration rate (GFR) is the primary indicator of renal function. Several equations have been proposed to evaluate the estimated GFR (eGFR). We compared three different equations to determine which has the better correlation with the development of acute and chronic renal failure in lung recipients. METHODS: Twenty-two patients with a mean age of 54.4 ± 8.5 years underwent lung transplantation from 2010 to 2015. Thirteen (59%) had pulmonary fibrosis, 7 (32%) emphysema, 1 (4.5%) bronchiectasis, and 1 (4.5%) lymphangioleiomyomatosis. In all patients, eGFR was measured preoperatively using Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), and Levey's Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. In 20 patients (90%) eGFR was calculated at 1, 3, and 6 months. RESULTS: According to CKD-EPI and MDRD, eight patients (36.3%) had preoperative reduction in eGFR, whereas 6 patients (27.2%) had preoperative reduction according to the CG (P = .04). The mean values were higher for the CG (103.2 vs. 102 vs. 94.4). Five patients (22.7%) developed perioperative acute renal failure requesting a dialysis treatment; four of these showed a preoperative eGFR to the highest CG (P = .05). At 1 and 6 months after lung transplantation, the CG, MDRD and CKD-EPI eGFR values were, respectively, 86.6, 84.1 and 76.6 mL/min/1.73m2 and 75.8, 72.7, and 72.3 mL/min/1.73m2. CKD-EPI eGFR values are more predictable than the other equations of AKI. CONCLUSIONS: Preoperative assessment of eGFR using the MDRD and CKD-EPI seems to correlate better than the CG to the prediction of acute renal failure, whereas for the chronic form the three equations seem equivalent.

Effects of dried plum supplementation on bone metabolism in adult C57BL/6 male mice.

Dietary supplementation of dried plum (DP) prevents bone loss and restores bone mass in osteopenic animal models. This study was designed to determine the effects of DP supplementation on bone metabolic activity over time using adult (6-month-old) male C57BL/6 mice (n = 40) receiving control (CON = AIN93 M) or CON+DP 25 % (w/w) diets for 4 or 12 weeks. After 4 weeks of treatment, animals consuming the DP diet had a higher whole-body bone mineral density, vertebral trabecular bone volume (BV/TV), and femoral cortical thickness compared to the CON animals. In the distal metaphysis of the femur, BV/TV was increased in the DP-treated animals, but only after 12 weeks. Bone histomorphometric analyses revealed that DP decreased osteoblast surface (67 %) and osteoclast surface (62 %) at 4 weeks, but these surfaces normalized to the CON animals by 12 weeks. Coincident with these changes, the mineralizing surface (MS/BS) and cancellous bone formation rate (BFR/BS) were reduced at 4 weeks in the DP group compared to the CON, but by 12 weeks of DP supplementation, BFR/BS (~twofold) and MS/BS (~1.7-fold) tended to be increased (p < 0.10). The relative abundance of RNA for key regulators of osteoblast and osteoclast differentiation and indicators of osteoblast activity were reduced in the DP group at 4 weeks with no difference between groups at 12 weeks. These results indicate that supplementing the diet with DP initially suppressed cancellous bone turnover, but a biphasic response occurs over time, resulting in a positive effect on bone mass and structure.

Efficacy and safety of fibrin sealant patch in the treatment of air leakage in thoracic surgery.

AIM: Air leakage represents a major problem in lung surgery. Absorbable fibrin sealant patch (AFSP), a collagen sponge coated with human fibrinogen and thrombin, can be used as an adjunct to primary stapling or suturing. This study compared the efficacy of AFSP with manual suturing after primary stapling. METHODS: This was a prospective, multicenter, randomized study. Patients undergoing lobectomy, bilobectomy, anatomical segmentectomy for lung cancer or wedge resection for pulmonary metastasis with air leakage grade 1 or 2 according to Macchiarini scale after stapler suture were randomized to receive AFSP or standard surgical treatment (ST). The primary endpoint was the reduction of intraoperative air leakage intensity. Duration of postoperative air leakage and number of days until removal of last chest drain were secondary endpoints. Safety was recorded for all patients. RESULTS: A total of 346 patients were enrolled in 14 centres, 179 of whom received AFSP and 167 ST. Intraoperative air leak intensity was reduced in 90.5% of AFSP patients and 82% of ST patients (P=0.03). A significant reduction in postoperative air leakage duration was observed in the AFSP group (P=0.0437). The median number of days until removal of last drainage was 6 (3-37) in the AFSP group and 7 (2-27) in the ST (P=0.38). Occurrence of adverse events was comparable in both groups. CONCLUSION: AFSP was more efficacious than standard ST as an adjunct to primary stapling in reducing intraoperative air leakage intensity and duration of postoperative air leakage in patients undergoing pulmonary surgery. AFSP was well tolerated.

Extracorporeal membrane oxygenation as bridge to lung transplantation.

Lung transplantation (OLT) is a viable option for end-stage pulmonary diseases in selected patients with satisfactory long-term results. However, the paucity of available donors engenders a prolonged stay on the waiting list with progressive decline of lung function. In cases of sudden respiratory failure, admission to an intensive care unit with institution of extracorporeal membrane oxygenation (ECMO) may be an option while a waiting an emergency OLT. In 12 OLT candidates we started ECMO because of acute decline of lung function. Eleven patients had cystic fibrosis and the other subject, histiocytosis X. In 7 patients bilateral OLT was performed after a mean waiting time of 6 days from ECMO institution; 5 patients died on ECMO at a mean time of 11.6 days. After OLT 2 patients required reoperation for hemothorax; renal failure and acute leg ischemia occurred in 2 patients. The mean weaning time from ECMO after OLT was 2.14 days. No patient died in the perioperative period and 1-year survival was 85.7%. ECMO represents a valid option as a bridge to urgent OLT for selected candidates.

Lung transplantation for cystic fibrosis: outcome of 101 single-center consecutive patients.

Bilateral sequential lung transplantation (BSLT) is nowadays considered a valid therapeutic option for patients with end stage cystic fibrosis. We report our experience with 104 BSLTs in 101 patients. The overall survivals at 1, 3, 5, 10 years were 79%, 65%, 58%, and 42%, respectively. Perioperative mortality was 14.8% (n = 15). The leading causes of perioperative mortality were primary graft dysfunction and sepsis. Three patients were retransplanted owing to obliterative bronchiolitis. In 70 cases (69%), patients displayed ≥ 1 additional risk factors: previous lung resections, colonization by Burkholderia cepacia, diabetes, pneumothorax, or noninvasive ventilatory support. The mean preoperative 1-second forced expiratory volume of 0.69 ± 0.2 L (22%) increased to 85% at 1 year after the operation. The mean time on the waiting list was 12 ± 5 months. The 5 patients treated with extracorporeal membrane oxygenation before urgent transplantation were operated after 3, 5, 6, 30, and 3 days respectively. During the procedure, cardiopulmonary bypass was required in 33 patients (32%). Lung transplantation represents a unique opportunity to ameliorate the quality and improve the survival of patients affected by cystic fibrosis. Timing of referral and patient selection remain crucial for success.

Pulmonary hypertension is associated with higher mortality in cystic fibrosis patients awaiting lung transplantation.

AIM: Pulmonary hypertension (PH) is frequently found in patients with advanced parenchymal lung diseases. In advanced stages, cystic fibrosis (CF) patients can develop PH and eventually cor pulmonale. Little is known about the prevalence of PH in CF patients and its impact on outcome. METHODS: We retrospectively studied a large cohort of CF patients evaluated for lung transplantation between 1995 and 2010. All the patients underwent right heart catheterization as part of the evaluation. We included 179 unique consecutive adult CF patients. Age was 24±9 years and 45.8% were women. RESULTS: Eighty-seven patients were transplanted (48.6%) and 65 died (36.3%) while waiting for LT. By right heart catheterization, 38.5% of the patients had PH (mean ≥25 mm Hg). PaCO(2) (P=0.045) and forced vital capacity (P=0.023) were independent predictors of PH in CF patients. The median survival (free of lung transplantation) was 13.4 months. After adjusting for several covariates, the presence of PH significantly increased mortality (hazard ratio, HR) (P<0.001). Pulmonary vascular resistance was associated with mortality (P=0.03). When both PH and PVR were included in the model, only PH predicted mortality. CONCLUSION: Pulmonary hypertension of mild degree is frequently found in CF patients with advanced lung disease and its presence significantly worsens survival.

Pulmonary hypertension is associated with higher mortality in cystic fibrosis patients awaiting lung transplantation.

AIM:Pulmonary hypertension (PH) is frequently found in patients with advanced parenchymal lung diseases. In advanced stages, cystic fibrosis (CF) patients can develop PH and eventually cor pulmonale. Little is known about the prevalence of PH in CF patients and its impact on outcome. METHODS: We retrospectively studied a large cohort of CF patients evaluated for lung transplantation between 1995 and 2010. All the patients underwent right heart catheterization as part of the evaluation. We included 179 unique consecutive adult CF patients. Age was 24±9 years and 45.8% were women. RESULTS:Eighty-seven patients were transplanted (48.6%) and 65 died (36.3%) while waiting for LT. By right heart catheterization, 38.5% of the patients had PH (mean ≥25 mm Hg). PaCO2 (P=0.045) and forced vital capacity (P=0.023) were independent predictors of PH in CF patients. The median survival (free of lung transplantation) was 13.4 months. After adjusting for several covariates, the presence of PH significantly increased mortality (hazard ratio, HR) (P<0.001). Pulmonary vascular resistance was associated with mortality (P=0.03). When both PH and PVR were included in the model, only PH predicted mortality. CONCLUSION: Pulmonary hypertension of mild degree is frequently found in CF patients with advanced lung disease and its presence significantly worsens survival.

Pneumonectomy: quality of life and long-term results.

AIM: Pneumonectomy is the standard surgery for resectable locally advanced lung cancer. Objectives of this study were: 1) to assess the overall survival; 2) to evaluate the pulmonary and cardiac function impairment; 3) to monitor quality of life (QoL) in a consecutive series of patients undergoing pneumonectomy, defining the potential risk factors of a poor prognosis. METHODS: From January 2003 to March 2010, 71 patients undergoing pneumonectomy for lung cancer or mesothelioma were prospectively enrolled in this study. Twenty-six patients underwent right pneumonectomy (2 of them underwent intrapericardial pneumonectomy), 31 left pneumonectomy (3 of them underwent intrapericardial pneumonectomy), 3 extended pneumonectomy, 3 extrapleural pneumonectomy and 5 patients underwent completion pneumonectomy. Three patients were not included in the study for early postoperative deaths (4.3%). All patients underwent complete preoperative assessment and one year after surgery. QoL was assessed by a questionnaire. RESULTS: One and five-year survival rate was 93% (N.=63) and 20% (N.=14), respectively. Mean values of FEV1 decreased from 2.59±0.75 L to 1.8±0.72 L (P<0.001). One year after surgery all patients showed moderate tricuspid valve insufficiency, PASP significantly higher and right ventricular free wall thickness moderately increased. An increased negative effect was recorded in the QoL scores with P<0.001. Three clinical and surgical parameters were identified as risk or protective factors for the survival outcome. CONCLUSION: Postoperative mortality (4.3%) and five-year survival (20%) after pneumonectomy seem to be satisfactory. Late cardiopulmonary insufficiency is uncommon and acceptable QoL is still achievable.

Lung transplantation for cystic fibrosis after thoracic surgical procedures.

During their life, cystic fibrosis (CF) patients may require thoracic surgical procedures for a number of reasons before undergoing lung transplantation. In the past, this has been considered to be a contraindication to lung transplantation. However, a meticulous surgical technique and careful intraoperative management allows one to perform the transplantation safely. Herein we have reported our experience with CF patients undergoing lung transplantation after previous surgical treatment for pneumothorax or bronchiectasis.

[T4 lung cancer: results of surgical treatment]. / Il tumore polmonare T4: risultati del trattamento chirurgico.

Stage T4 non small cell lung cancer (NSCLC) includes an heterogeneous group of locally advanced tumors. Results of surgery alone and of chemo and/or radiotherapy are disappointing with 5-year survival rates under 10%. Although palliative chemo-radiotherapy is the treatment of choice in most cases, radical resection has shown prognostic benefit in selected groups of patients with tumor infiltrating Superior Vena Cava, carina, aorta, left atrium and vertebral bodies. Completeness of resection and absence of mediastinal nodal involvement are fundamental conditions for the long-term success of surgery. Increased postoperative 30-day mortality and 90-day mortality rates have been reported up to 8% and 18% respectively. Neoadjuvant therapy, in the last decades, has shown to improve survival of T4 NSCLC patients undergoing surgery and to increase the number of patients suitable for surgical resection. Surgical resection is not indicated in patients with neoplastic pleural effusion since it is generally related to a worse prognosis in such cases. Conversely, patients with T4 tumor due to neoplastic satellite nodule in the same lobe are good surgical candidates. In some studies, these patients show a significant survival advantage after surgical treatment with respect to patients with other types of T4 tumors, when no mediastinal nodal involvement is associated.

Treatment of complex airway lesions after lung transplantation with self-expandable nitinol stents: early experience.

Airway complications (AC) are considered a serious cause of morbidity after lung transplantation (LT). Mechanical dilatation, laser vaporization, and silicone stent placement usually solve it. However, the use of self-expandable metallic stents (SENS) may be indicated in selected cases. Ten lung transplant recipients with AC were treated with SENS. Six patients underwent LT for cystic fibrosis, 2 for idiopathic pulmonary fibrosis, 1 for bronchiectasis, and 1 for emphysema. All patients received at least 1 treatment attempt with dilatation and silicone stent placement. The indications for SENS placement were the presence of a tortuous airway axis with stenosis and malacia of the right main bronchus in 5 patients; a long stenosis of the main and intermediate right bronchus involving the upper lobe orifice in 3 patients; or malacia that could not be stabilized with silicone stents in 3 cases. In 1 patient the procedure was bilateral. Functional improvement was immediate with a mean forced expiratory volume at 1 second (FEV(1)) gain of 35%. No stent dislocation was observed. Symptoms did not occur again in 5 patients with previous recurrent episodes of pneumonia. One stenosis, which was due to the ingrowth of granulation tissue occurred at 6 months after the procedure, was successfully treated with mechanical dilatation and laser vaporization. The deployment of SENS in a selected group of patients with AC after LT was easy, safe, and effective.

Extracorporeal circulatory support for lung transplantation: institutional experience.

Lung transplantation (LT) represents the only available therapy for selected patients affected by end-stage pulmonary disease. Cardiopulmonary bypass (CPBP) is used, when required, during single and sequential double lung transplantation; however, it increases the risk of bleeding, early graft dysfunction, failure, and other potential side effects. We report our experience with 145 patients who underwent lung transplantations, among whom 34 required intraoperative CPBP. The indications for LT among these 34 patients were cystic fibrosis (n = 22), chronic obstructive pulmonary disease (n = 3), bronchiectasis (n = 2), primary pulmonary hypertension (n = 1), fibrosis (n = 2), pulmonary microlithiasis (n = 1), and retransplantation for obliterative bronchilitis (n = 3). CPBP was planned in 12 cases (group I) and unplanned in 22 (group II). The main reason for planning CPBP was primary and secondary pulmonary hypertension (mean pulmonary artery pressure >or=25 mm Hg). Acute right ventricular failure, hemodynamic instability, arterial desaturation, and increased pulmonary artery pressure were mandatory for unplanned CPBP. Among the 34 CPBP patients, the 30-day mortality rate was 35% (12/34) including 9 (70%) in group II (unplanned CPBP). The leading cause of death was multiorgan failure. The 1-year survival rates were 67% and 36%, and the 3-year survival rates were 47% and 18% for groups I and II, respectively. In conclusion, even if it represents a useful tool in the management of critical events, the use of unscheduled CPBP during LT procedures is associated with an increased postoperative morbidity and mortality.

Tracheal surgery.

Surgical resection and reconstruction of the trachea can be performed both for benign and malignant diseases. The main indications for surgery include inflammatory (generally post-intubation), congenital or post-traumatic stenoses, degenerative lesions, benign or malignant neoplasms. Success can be pursued only by accurate patient selection and timing, meticulous surgical techniques, careful follow up and, when required, multidisciplinary cooperation. Although surgical resection has now become part of our surgical practice, other treatment modalities are approaching a new clinical application era, in particular tracheal transplantation and bioengineering. These new techniques will certainly offer, in the near future, improved chances to treat difficult cases.

Autologus platelet gel for the management of persistent alveolar fistula after lung resection.

Postoperative alveolar fistula (AF) associated with pleural cavity (PC) is a serious complication and a therapeutic challenge in thoracic surgery. The purpose of this study was to assess the efficacy of the use of the autologous platelet gel for the treatment of AF and PC. We treated a patient with post lung resection persistent alveolar fistula using a autologous platelet gel, a cellular compose produces at the Division of Immunohaematoligy and Trasfusion. The platelet gel-PRP (Platelet-Rich Plasma) is a biological material made of autologous platelets, extracted from a small amount of the patient's blood, centrifuged at 1100 g for 9 min. The PRP obtained was activated by addition of autologous thrombin and calcium chloride to form a matrix of fibrin (PRFM) thick. The patient presented important air leak after middle lobe wedge resection for solitary lung lesion with standard open decortication for important pleural adhesions post pleuritis. On postoperative day XIII the patient developed a thoracic empyema and consequently underwent a antibiotic pleural irrigation through the chest drainage based on the microbiological analysis of the pleural fluid. After a week we obtained the resolution of the empyema but a residual space remained and air leak persisted. We treated the patient with autologous platelet gel. We administer 7.5 mL of the autologous platelet gel across the chest drainage ever 72 hours for 3 times. After the third application we had the closure of the cavity and the cessation of air leak. Autologous platelet gel is easy to use, safe and inexpensive. It can be considered a valid therapeutic option in selected patients with a alveolar fistula and a lung partial re-expansion. The product consist of a significant amount of cellular components with healing anti-inflammatory an proregenerative properities that permit the body to heal tissue wounds faster and more efficiently. A sterile pleural cavity is fundamental conditions for the final success of the procedure.

Plasma NT-proBNP levels and the risk of atrial fibrillation after major lung resection.

AIM: Supraventricular tachyarrhythmias, most frequently atrial fibrillation (AF), occur in 8-30% of patients undergoing major pulmonary resection. The aim of this study was to characterize a biochemical marker in order to identify subjects at higher risk of postoperative AF. The authors tested the hypothesis that elevated preoperative plasma levels of N-terminal brain-type natriuretic peptide (NT-pro-BNP) may predict the occurrence of postoperative AF. METHODS: Fifty-five consecutive patients undergoing elective major thoracic surgery were selected. All patients had 12-lead electrocardiogram and transthoracic echocardiographic evaluation at entry. Plasma NT-pro BNP levels were determined both at baseline and at the first postoperative day. Patients were monitored thereafter to detect the occurrence of AF. For statistical analysis, an unpaired Student t test was used to compare continuous variables, chi(2) tests or Fischer exact tests were used for categorical variables, as needed. RESULTS: Eight (14.54%) of the 55 patients developed AF with a peak incidence on postoperative days 2 to 3. Baseline NT-pro-BNP was more than two fold higher in patients who developed AF (506.1+/-108.4 pg/mL versus 197.7+/-54.9 pg/mL; P=0.001). Other relevant clinical and diagnostic parameters were not different in the two groups. Patients with NT-pro-BNP level above the median (113.0 pg/mL) had 8-fold increase risk of postoperative AF. CONCLUSION: A preoperative elevated plasma NT-pro-BNP level was associated with the occurrence of AF in patient undergoing major thoracic surgery. Baseline NT-pro-BNP levels may be proposed as a biochemical marker to detect patients at higher risk of postoperative AF who could benefit from prophylactic therapeutic medication.

Lung transplantation for cystic fibrosis: ten years of experience.

Lung transplantation represents the only therapeutic option for patients affected by end-stage cystic fibrosis (CF). We performed 76 lung transplantations in 73 patients from 1996-2007. The mean time on the waiting list was 10+/-6 months. The median follow-up after the transplantation was 69.3 months. Twenty-one transplants (27.6%) were performed under cardiopulmonary bypass. Perioperative mortality, excluding retransplants, was 16.4% (12 patients) and the causes of death were sepsis, primary graft failure, and myocardial infarction. The overall survival was 74.5%+/-5%, 62.9%+/-5%, 54.1%+/-6%, and 43.4%+/-6% at 1, 3, 5, and 10 years, respectively. The accurate selection of potential recipients and the correct timing of referral and transplantation are factors that play crucial roles to obtain satisfactory results in term of improvement of quality of life and long-term survival.

Malignancies following lung transplantation.

During the last 2 decades, long-term survival after lung transplantation has significantly improved. However, among the complications related to the continuous administration of immunosuppressive drugs, malignancy plays an important role. We retrospectively revisited our series of patients to report our experience. From January 1991 we performed 134 lung transplantations in 128 recipients (mean age, 33.4 +/- 13.5 years). In all patients the first-line immunosuppressive regimen was based on a calcineurin inhibitor (cyclosporine or tacrolimus), an antimetabolic agent (azathioprine), and steroids. Five patients (4.2%) developed malignancy and the mean time of occurrence after the transplantation was 46.4+/-23 months. The mean age was 41 +/- 16 years (P = not significant [ns]). The tumors were as follows: laryngeal cancer (radiotherapy), colon cancer (surgery plus adjuvant chemotherapy), gastric cancer (surgery plus adjuvant chemotherapy), endobronchial non-Hodgkin lymphoma (NHL) (endoscopic resection plus chemoradiotherapy), and cutaneous and visceral Kaposi's sarcoma (KS) (chemotherapy). All patients have reduced the dose of immunosuppressive drugs; in 1 of them, tacrolimus was changed to rapamycin. Two patients died because of neoplastic dissemination, another 1 due to obliterans bronchiolitis. The 2 patients with NHL and KS are alive at 6 and 9 months, respectively, without signs of recurrence. Malignancies after lung transplantation represent an important problem. A multidisciplinary approach is mandatory to obtain satisfactory results in terms of improved quality of life and long-term survival.

Expression of autoimmune regulator gene (AIRE) and T regulatory cells in human thymomas.

Expression of the autoimmune regulator gene (AIRE) and the presence of CD25(+)/forkhead box p3 (FoxP3)(+) T regulatory (T(reg)) cells were investigated in histologically normal adult thymi and in thymomas using immunohistochemistry and quantitative real-time polymerase chain reaction (PCR). In the normal thymus staining for AIRE was detected in the nucleus of some epithelial-like cells located in the medulla; in thymomas AIRE-positive cells were extremely rare and could be detected only in the areas of medullary differentiation of two B1 type, organoid thymomas. RNA was extracted from 36 cases of thymoma and 21 non-neoplastic thymi obtained from 11 myasthenic (MG(+)) and 10 non-myasthenic (MG(-)) patients. It was found that AIRE is 8.5-fold more expressed in non-neoplastic thymi than in thymomas (P = 0.01), and that the amount of AIRE transcripts present in the thymoma tissue are not influenced by the association with MG, nor by the histological type. A possible involvement of AIRE in the development of MG was suggested by the observation that medullary thymic epithelial cells isolated from AIRE-deficient mice contain low levels of RNA transcripts for CHRNA 1, a gene coding for acetylcholine receptor. Expression of human CHRNA 1 RNA was investigated in 34 human thymomas obtained from 20 MG(-) patients and 14 MG(+) patients. No significant difference was found in the two groups (thymoma MG(+), CHRNA1 = 0.013 +/- 0.03; thymoma MG-, CHRNA1 = 0.01 +/- 0.03). In normal and hyperplastic thymi CD25(+)/Foxp3(+) cells were located mainly in the medulla, and their number was not influenced by the presence of MG. Foxp3(+) and CD25(+) cells were significantly less numerous in thymomas. A quantitative estimate of T(reg) cells revealed that the levels of Foxp3 RNA detected in non-neoplastic thymi were significantly higher (P = 0.02) than those observed in 31 cases of thymomas. Our findings indicate that the tissue microenvironment of thymomas is defective in the expression of relevant functions that exert a crucial role in the negative selection of autoreactive lymphocytes.