In solid tumors, neoadjuvant or adjuvant immune checkpoint blockade increases treatment-related grade 3 or 4 adverse events.

SOURCE CITATION: Fujiwara Y, Horita N, Adib E, et al. Treatment-related adverse events, including fatal toxicities, in patients with solid tumours receiving neoadjuvant and adjuvant immune checkpoint blockade: a systematic review and meta-analysis of randomised controlled trials. Lancet Oncol. 2024;25:62-75. 38012893.

Joint ERS/EACTS/ESTS clinical practice guidelines on adults with spontaneous pneumothorax.

BACKGROUND: The optimal management for spontaneous pneumothorax (SP) remains contentious, with various proposed approaches. This joint clinical practice guideline from the ERS, EACTS and ESTS societies provides evidence-based recommendations for the management of SP. METHODS: This multidisciplinary Task Force addressed 12 key clinical questions on the management of pneumothorax, using ERS methodology for guideline development. Systematic searches were performed in MEDLINE and Embase. Evidence was synthesised by conducting meta-analyses, if possible, or narratively. Certainty of evidence was rated with GRADE (Grading of Recommendations, Assessment, Development and Evaluations). The Evidence to Decision framework was used to decide on the direction and strength of the recommendations. RESULTS: The panel makes a conditional recommendation for conservative care of minimally symptomatic patients with primary spontaneous pneumothorax (PSP) who are clinically stable. We make a strong recommendation for needle aspiration over chest tube drain for initial PSP treatment. We make a conditional recommendation for ambulatory management for initial PSP treatment. We make a conditional recommendation for early surgical intervention for the initial treatment of PSP in patients who prioritise recurrence prevention. The panel makes a conditional recommendation for autologous blood patch in secondary SP patients with persistent air leak (PAL). The panel could not make recommendations for other interventions, including bronchial valves, suction, pleurodesis in addition to surgical resection or type of surgical pleurodesis. CONCLUSIONS: With this international guideline, the ERS, EACTS and ESTS societies provide clinical practice recommendations for SP management. We highlight evidence gaps for the management of PAL and recurrence prevention, with research recommendations made.

The Incidence of Winged Scapula after Thoracic Cancer Surgery: A Prospective Cohort Study.

BACKGROUND: Lung cancer is the leading cause of cancer-related deaths, and surgery is still the first treatment of choice in early and locally advanced cases. One of the iatrogenic complications is the serratus anterior palsy, which could lead to a winged scapula (WS). Unfortunately, the incidence of this deficit in thoracic surgery is unclear. Our primary aim was to determine the incidence of WS in lung cancer patients in a single-center experience. METHODS: We conducted a retrospective analysis of prospectively collected data with patients eligible for oncological thoracic surgery from March 2013 until January 2014. A physical evaluation of the WS was performed pre- and postoperatively, at the discharge and after 1 year of follow-up. RESULTS: A total of 485 patients were evaluated; 135 (27.8%) showed WS. Longer operative time (p < 0.0001), type of surgery (p < 0.0001), lymphadenectomy (p < 0.0001), and neoadjuvant treatment prior surgery (p = 0.0005) were significantly related to the WS injury. Multivariable analysis showed that type of surgery was significantly associated with WS (p < 0.0001). After 1 year, 41.6% still had WS. CONCLUSION: The incidence of WS was similar to the literature. As WS incidence is underdiagnosed, assessment and correct education about possible deficits or impairments should be improved. Moreover, when a minimally invasive approach is not planned, it is a good clinical practice to discuss surgical strategies with surgeons to reduce this deficit.

A prognostic score from a multicentric retrospective analysis of patients affected by sarcoma with metachronous lung metastases undergoing metastasectomy.

BACKGROUND: Despite the lack of evidence-based on prospective randomized studies, surgery has become the cornerstone of the treatment in patients with pulmonary oligometastatic sarcomas. Our study aimed to construct a composite prognostic score for metachronous oligometastatic sarcoma patients. METHODS: A retrospective analysis was performed on data patients who underwent radical surgery for metachronous metastases in six research institutes from January 2010 to December 2018. The log-hazard ratio (HR) obtained from the Cox model was used to derive weighting factors for a continuous prognostic index designed to identify differential outcome risks. RESULTS: A total of 251 patients were enrolled in the study. In the multivariate analysis, a longer disease-free interval (DFI) and a lower neutrophil-to-lymphocytes ratio (NLR) were predictive of a better overall survival (OS) and disease-free survival (DFS). A prognostic score was developed based on DFI and NLR data, identifying 2 risk class groups for DFS (3-years DFS 20.2% for the high-risk group [HRG]and 46.4% for the low-risk group [LRG] [<0.0001]) and 3 risk groups for OS (3 years OS 53.9% for the HRG vs. 76.9% for the intermediate-risk group and 100% of the LRG (p < 0.0001)). CONCLUSION: The proposed prognostic score effectively predicts outcomes for patients with lung metachronous oligo-metastases from the surgically treated sarcoma.

Assessment of the 90-day mortality risk score after video-assisted thoracoscopic lobectomy in the Italian VATS Group cohort.

A five classes (A-E) aggregate risk score predicting 90-day mortality after video-assisted thoracoscopic lobectomy for lung cancer, including as independent factors male sex (3 points), DLCO <60% (1 point) and operative time >150 minutes (1 point), has been recently published. This study aims to assess the effectiveness and reliability of this risk model in a large, independent cohort of patients, to confirm its generalizability. From the Italian VATS Group Database, we selected 2,209 patients [60% males; median age 69 years (IQR:63-74)] who underwent video-assisted thoracoscopic lobectomy for non-small cell lung cancer. We calculated the aggregate risk score and the corresponding class of 90-day mortality risk for each patient. The correlation between risk classes and mortality rates was tested by Spearman's r-test. Model calibration was evaluated by Hosmer-Lemeshow goodness-of-fit test. Class A-E 90-day mortality rates were 0.33%, 0.51%, 1.39%, 1.31% and 2.56%, respectively. A strong uphill correlation was identified between risk classes and 90-day mortality (r=0.90; p=0.037), showing a positive correlation between increased mortality rate and class A to E. Hosmer-Lemeshow chi-squared value was 67.47 (p<0.001) with overall, Class D and E significantly lower 90-day mortality in our cohort than in the original one [1.04% vs 2.5% (p=0.018), 1.31% vs 5.65% (p=0.005) and 2.56% vs 18.75% (p=0.007), respectively]. Despite our data show a positive correlation between 90-day mortality and risk classes from A to E with modest discriminatory performance, the poor calibration suggests the need for model recalibration using local data to better manage and counsel lung cancer patients eligible for video-assisted thoracoscopic lobectomy.

Multimodal therapy for synchronous bone oligometastatic NSCLC: The role of surgery.

OBJECTIVES: The study aimed to assess the feasibility of radical surgical treatment for selected bone-oligometastatic non-small cell lung cancer (NSCLC) patients and to identify prognostic factors associated with survival. MATERIALS AND METHODS: The clinical records of 27 patients with bone synchronous oligometastatic NSCLC were retrospectively analyzed. RESULTS: Thirteen (48.1%) bone metastases were treated by surgery and 14 (51.9%) by local radiotherapy. Eighteen (66.7%) patients underwent induction chemotherapy before lung surgery, and 3 (11.1%) concurrent radiotherapy. Pulmonary surgery was a major lung resection in 23 (85.2%) cases. Intraoperative and 30-days mortality was null. Only one major (ARDS) and 10 (37.04%) mild complications (like air leakage, arrhythmia, and mucus retention) were recorded. 1-year and 5-years OS from the diagnosis and 1-year, 3- years disease-free survival (DFS) were 96%, 38%, and 66%, 30%, respectively. After stepwise Cox regression analysis, local recurrence (p = 0.05) and metachronous metastases (p = 0.04) maintained their independent prognostic value as overall survival negative determinants. Nodal upstaging (p = 0.04) and nonsurgical treatment of bone lesion (p = 0.03) turned out to be independent risk factors for shorter DFS; the vertebral localization of bone metastases showed only a remarkable trend towards significance (p = 0.06) as a risk factor for a worse DFS. CONCLUSIONS: In selected patients, surgical treatment of primary NSCLC and bone synchronous metastasis seems to be safe and feasible and rewarding survivals may be expected.

The Weekday Effect on Morbidity of Lung Cancer Surgery: A Real-World Analysis.

BACKGROUND: Many authors have investigated the possible adverse effects among patients who underwent elective surgery on Friday when compared with patients operated earlier in the week. Nonetheless, the weekday effect is still a matter of debate. This study aimed at investigating the postoperative morbidity rates after lung cancer surgery and their relationship with the weekday the surgery took place. MATERIALS AND METHODS: We retrospectively reviewed the clinical records of patients who underwent elective thoracotomic lobectomies for lung cancer. Categorical data were analyzed using the chi-square test or Fisher's exact test. Association between predictors and binary outcomes while considering the weekday stratification was determined with Cochran-Mantel-Haenszel statistics. To characterize the typical Friday patient, a multiple logistic regression analysis was performed. RESULTS: A total of 817 patients (2015-2019) were identified. Complication rates divided by day of surgery were 164 (20.07%) for patients operated on Mondays, 182 (22.27%) on Tuesdays, 205 (25.09%) on Wednesdays, 172 (21.05%) on Thursdays, and 94 (11.51%) on Fridays. Crude morbidity rates by weekday were Monday 21.53%, Tuesday 20.51%, Wednesday 27.70%, Thursday 20.0%, and Friday 10.26%. No overall association between day of surgery and overall morbidity was found (ρ = 0.095). Median hospital length of stay was 5 days (range: 2-45 days), and there were no statistically significant differences between days. The Cochran-Mantel-Haenszel statistics showed no association between morbidity and the weekday. CONCLUSION: In patients undergoing elective lobectomies for lung cancer, the weekday of surgery was not statistically significantly associated with an increase in the risk of postoperative morbidity.

Safety Analysis of Salvage Surgery for Advanced Stages or Metastatic Lung Cancers.

This case series aimed to analyze the outcomes of patients referred for salvage pulmonary resections after treatment with chemotherapy and immunotherapy for previously metastatic or unresectable tumors.From October 2016, after multidisciplinary board discussion, eight patients (median: 67 years, range: 52-78 years) underwent medical treatment due to advanced-stage diseases (stage cIIIA-cIVa). Four patients underwent cisplatin-based chemotherapy and, due to progression, were moved to an immunotherapy second line (nivolumab: two patients and pembrolizumab: two patients). Instead, four patients underwent combined cisplatin-based chemotherapy and immune checkpoint inhibitors (atezolizumab: two patients and pembrolizumab: two patients). After a multidisciplinary evaluation for salvage surgery, six patients underwent lobectomies, one patient underwent left pneumonectomy, and one patient underwent upper right lobectomy enlarged to the posterior arches of four ribs. The median duration of surgery was 179 minutes (range: 122-246 minutes). At the final pathological stage, three patients showed a complete major response (ypT0 ypN0), one patient was ypT1a ypN0, one ypT3 ypN0, 2 ypT3 ypN1, and one ypT4 ypN0. The hospital length of stay was 6 days (range: 3-23 days). Two patients had a postoperative complication. At the time of follow-up (median: 15.3 months [range: 1-32 months]), six patients were alive without evidence of the recurrence. Two patients died due to recurrence progression (N3 lymph nodes involvement) of the disease after 6 and 32 months.In stage IIIB-IVA nonsmall cell lung cancer, salvage lung surgeries after chemotherapy and immunotherapy are feasible, with high rates of R0 resection. Surgery can be technically tricky without significant morbidity and encouraging outcomes (even with a short-interval follow-up).

Autologous Blood Pleurodesis: What Is the Optimal Time Interval and Amount of Blood?

BACKGROUND: Air leak is the most common complication after lung resection and leads to increased length of hospital (LOH) stay or patient discharge with a chest tube. Management by autologous blood patch pleurodesis (ABPP) is controversial because few studies exist, and the technique has yet to be standardized. METHODS: We retrospectively reviewed patients undergoing ABPP for prolonged air leak (PAL) following lobectomy in three centers, between January 2014 and December 2019. They were divided into two groups: Group A, 120 mL of blood infused; Group B, 60 mL. Propensity score-matched (PSM) analysis was performed, and 23 patients were included in each group. Numbers and success rates of blood patch, time to cessation of air leak, time to chest tube removal, reoperation, LOH, and complications were examined. Univariate and multivariate analysis of variables associated with an increased risk of air leak was performed. RESULTS: After the PSM, 120 mL of blood is statistically significant in reducing the number of days before chest tube removal after ABPP (2.78 vs. 4.35), LOH after ABPP (3.78 vs. 10.00), and LOH (8.78 vs. 15.17). Complications (0 vs. 4) and hours until air leak cessation (6.83 vs. 3.91, range 1-13) after ABPP were also statistically different (p < 0.05). Air leaks that persisted for up to 13 hours required another ABPP. No patient had re-operation or long-term complications related to pleurodesis. CONCLUSION: In our experience, 120 mL is the optimal amount of blood and the procedure can be repeated every 24 hours with the chest tube clamped.

Outcomes of patients discharged home with a chest tube after lung resection: a multicentre cohort study.

BACKGROUND: Prolonged air leaks are increasingly treated in the outpatient setting, with patients discharged with chest tubes in place. We evaluated the incidence and risk factors associated with readmission, empyema development and further interventions in this patient population. METHODS: We undertook a retrospective cohort analysis of all patients from 4 tertiary academic centres (January 2014 to December 2017) who were discharged home with a chest tube after lung resection for a postoperative air leak lasting more than 5 days. We analyzed demographics, patient factors, surgical details, hospital readmission, reintervention, antibiotics at discharge, empyema and death. RESULTS: Overall, 253 of 2794 patients were analyzed (9.0% of all resections), including 30 of 759 from centre 1 (4.0%), 67 of 857 from centre 2 (7.8%), 9 of 247 from centre 3 (3.6%) and 147 of 931 from centre 4 (15.8%) (p < 0.001). Our cohort consisted of 56.5% men, and had a median age of 69 (range 19-88) years. Despite similar initial lengths of stay (p = 0.588), 49 patients (19.4%) were readmitted (21%, 0%, 23% and 11% from centres 1 to 4, respectively, p = 0.029), with 18 (36.7%) developing empyema, 11 (22.4%) requiring surgery and 3 (6.1%) dying. Only chest tube duration was a significant predictor of readmission (p < 0.001) and empyema development (p = 0.003), with a nearly threefold increased odds of developing empyema when the chest tube remained in situ for more than 20 days. CONCLUSION: Discharge with chest tube after lung resection is associated with serious adverse events. Given the high risk of empyema development, removal of chest tubes should be considered, when appropriate, within 20 days of surgery. Our data suggest a potential need for proactive postdischarge outpatient management programs to diminish risk of morbidity and death.

Preliminary Results of Extracorporeal Membrane Oxygenation Assisted Tracheal Sleeve Pneumonectomy for Cancer.

OBJECTIVE: Tracheal sleeve pneumonectomy is a challenge in lung cancer management and in achieving long-term oncological results. In November 2018, we started a prospective study on the role of extracorporeal membrane oxygenation (ECMO) in tracheal sleeve pneumonectomy. We aim to present our preliminary results. METHODS: From November 2018 to November 2019, six patients (three men and three women; median age: 61 years) were eligible for tracheal sleeve pneumonectomy for lung cancer employing the veno-venous ECMO during tracheobronchial anastomosis. RESULTS: Only in one patient, an intrapericardial pneumonectomy without ECMO support was performed, but cannulas were maintained during surgery. The median length of surgery was 201 minutes (range: 162-292 minutes), and the average duration of the apneic phase was 38 minutes (range: 31-45 minutes). No complications correlated to the positioning of the cannulas were recorded. There was only one major postoperative complication (hemothorax). At the time of follow-up, all patients were alive; one patient alive with bone metastasis was being treated with radiotherapy. CONCLUSION: ECMO-assisted oncological surgery was rarely described, and its advantages include hemodynamic stability with low bleeding complications and a clean operating field. As suggested by our preliminary data, ECMO-assisted could be a useful alternative strategy in select lung cancer patients.

Treatment of Chylothorax after Lung Resection: Indications, Timing, and Outcomes.

BACKGROUND: Chylothorax following pulmonary resection and lymphadenectomy for cancer is a potential severe complication in thoracic surgery. In the present study, we investigated the efficacy of the nonsurgical approach as well as the need for reoperation after conservative approach failure. METHODS: Chylothorax was diagnosed when chylous leakage from the chest drainage was observed and confirmed by the presence of triglycerides in the pleural fluid. We initially treated all the patients conservatively with complete oral intake cessation and total parenteral nutrition; if drainage output remained more than 800 mL/d after the first 5 days or major pleural effusion was observed at chest X-ray after chest tube removal, surgical treatment of chylothorax was indicated. RESULTS: Between January 1998 and December 2018, 5,072 patients underwent standard anatomical resection and mediastinal lymph node dissection for cancer at our institution. Among them, 30 patients (0.6%) developed chylothorax: 20 patients were effectively treated only by nil per os and low-fat diet, while 10 patients (33.3%) required surgical treatment. Mean age was 63 years; there were 24 male patients (80%); right-sided chylothorax was more frequent than left-sided chylothorax (22 vs. 8, respectively) although not statistically significant (p = 0.38); the only factor that seems to influence the need for reoperation is chylothorax flow rate during conservative treatment (p = 0.06). CONCLUSION: Conservative treatment is effective in the case of low flow-rate chylothorax (< 800 mL/d); in the case of a higher flow rate, surgical exploration is needed and thoracic duct ligation-with or without lymphatic sites clipping-provides definitive lymphostasis.

Age and Clinical Presentation for Primary Spontaneous Pneumothorax.

Primary spontaneous pneumothorax (PSP) is a commonly known condition due to the accumulation of air in the pleural space in otherwise healthy people, without apparent underlying lung disease. To date, the exact pathogenesis of PSP is unclear, but it still represents a public health issue. We performed a review of the literature concerning the epidemiology of PSP, examining age of onset and presentation symptoms, in order to assess the possible correlation between these characteristics and its occurrence. Data concerning age, signs, and symptoms were collected. For description purposes, information regarding aetiological and anthropomorphic data was also gathered. In total, 265 papers were evaluated. Regarding age of onset, PSP is a disease that can occur in a broad age group with a double cluster (15-30 and 40-45 yr). Regarding symptoms, pain and dyspnoea (in its various forms) are the most described in PSP. Pain was recorded in 69.25% (range, 9-100%) of the population studied, whereas dyspnoea was present in an average of 54.55% (range, 27-77.1%). Tobacco exposure seems to play an important role in the early onset of PSP. Concerning age at presentation, this review highlights that PSP can occur over a broad age range. The literature appears to be consistent in reporting PSP occurrence mostly below 45 years of age. Asymptomatic PSP is an almost unseen entity. Finally, of pollutants, cigarette smoking should be considered as the most significant exogenous risk factor in the development of PSP.

Enhanced Recovery After Surgery (ERAS®) in thoracic surgical oncology.

Enhanced recovery after surgery (ERAS®) is a strategy that seeks to reduce patients' perioperative stress response, thereby reducing potential complications, decreasing hospital length of stay and enabling patients to return more quickly to their baseline functional status. The concept was introduced in the late 1990s and was first adopted for use with patients undergoing open colorectal surgery. Since that time, the concept of ERAS has spread to multiple surgical specialties. This article explores the key elements for patient care using an ERAS protocol applied to minimally invasive thoracic surgery.

2016 Annual report from the Italian VATS Group.

This report highlights the results of the Italian video-assisted thoracoscopic surgery (VATS) Group, launched in mid 2013, which now has a website and an established database with over 4000 VATS lobectomy cases recruited from 67 thoracic surgery units across Italy. The year 2016 has been crucial for the following steps: inclusion of a dedicated biostatistician and a 'Survey Analysis & Data Quality Check'; the First Consensus Meeting with statements consequently adopted as Recommendations for the Italian Thoracic Surgery Society and published in a peer-reviewed journal; two papers published under the logo Italian VATS Group and seven abstracts accepted at annual international meetings (European Society of Thoracic Surgeons, European Association of Cardio-Thoracic Surgeons, European Lung Cancer Conference and European Respiratory Society); the institution of a Master Course on VATS lobectomy; the partnership with AME Publishing Company.

Comparison of digital tomosynthesis and computed tomography for lung nodule detection in SOS screening program.

PURPOSE: To compare the lung nodules' detection of digital tomosynthesis (DTS) and computed tomography (CT) in the context of the SOS (Studio OSservazionale) prospective screening program for lung cancer detection. MATERIALS AND METHODS: One hundred and thirty-two of the 1843 subjects enrolled in the SOS study underwent CT because non-calcified nodules with diameters larger than 5 mm and/or multiple nodules were present in DTS. Two expert radiologists reviewed the exams classifying the nodules based on their radiological appearance and their dimension. LUNG-RADS classification was applied to compare receiver operator characteristics curve between CT and DTS with respect to final diagnosis. CT was used as gold standard. RESULTS: DTS and CT detected 208 and 179 nodules in the 132 subjects, respectively. Of these 208 nodules, 189 (91%) were solid, partially solid, and ground glass opacity. CT confirmed 140/189 (74%) of these nodules but found 4 nodules that were not detected by DTS. DTS and CT were concordant in 62% of the cases applying the 5-point LUNG-RADS scale. The concordance rose to 86% on a suspicious/non-suspicious binary scale. The areas under the curve in receiver operator characteristics were 0.89 (95% CI 0.83-0.94) and 0.80 (95% CI 0.72-0.89) for CT and DTS, respectively. The mean effective dose was 0.09 ± 0.04 mSv for DTS and 4.90 ± 1.20 mSv for CT. CONCLUSIONS: The use of a common classification for nodule detection in DTS and CT helps in comparing the two technologies. DTS detected and correctly classified 74% of the nodules seen by CT but lost 4 nodules identified by CT. Concordance between DTS and CT rose to 86% of the nodules when considering LUNG-RADS on a binary scale.

Lymph Node Involvement in Deep Infiltrating Intestinal Endometriosis: Does It Really Mean Anything?

STUDY OBJECTIVE: To review our data for any correlation between the severity of endometriosis and lymph node involvement. DESIGN: Observational study with control (Canadian Task Force classification III). SETTING: Public medical center. PATIENTS: All women who underwent laparoscopic segmental rectal resection for endometriosis at our institution (Sacro Cuore Negrar Hospital) between 2000 and 2010. INTERVENTIONS: We retrospectively included 140 cases of colorectal surgery for intestinal endometriosis performed between 2004 and 2010 in our institution. Based on histopathological analysis of specimens, we divided our population into 2 groups: 70 patients with lymph node involvement and 70 patients without lymph node involvement. MEASUREMENTS AND MAIN RESULTS: No statistical correlation was found between the positivity of lymph nodes and the rate of intestinal stenosis, the histopathological specimen infiltration rate and depth and the intestinal recurrence rate. Only a poor correlation was found with preoperative CA-125 serous levels. CONCLUSION: The presence of lymph nodes involvement in intestinal resection specimens does not modify the natural history of the disease. The reason of its presence still has to be determined.

Ergon-trial: ergonomic evaluation of single-port access versus three-port access video-assisted thoracic surgery.

BACKGROUND: Single-port access video-assisted thoracic surgery (VATS), a technique progressively developed from the standard three-port approach in minimally invasive surgery, offers ergonomic advantages but also new challenges for the surgeon. We compared the ergonomics of three-port versus single-port VATS. METHODS: Posture analysis of surgeons was evaluated during 100 consecutive VATS wedge resections (50 triportal vs. 50 uniportal). Technically demanding procedures (major lung resection) were excluded. Operating table height, monitor height, distance and inclination were adjusted according to operator preference. Body posture was assessed by measuring head-trunk axial rotation and head flexion. Perceived physical strain was self-evaluated on the Borg Category Ratio (CR-10) scale. Mental workload was assessed with the National Aeronautics Space Administration-Task Load indeX (NASA-TLX), a multidimensional tool that rates workloads on six scales (mental, physical and temporal demand; effort; performance; frustration). RESULTS: All procedures were completed without complications. Head-trunk axial rotation was significantly reduced and neck flexion significantly improved in uniportal VATS. Viewing direction significantly declined (p = 0.01), body posture as measured on the Borg CR-10 scale was perceived as more stressful and the NASA-TLX score for overall workload was higher (p = 0.04) during triportal VATS. The NASA-TLX score for frustration was higher with uniportal VATS (p = 0.02), but the score for physical demand was higher in triportal VATS (p = 0.006). CONCLUSIONS: The surgeon can maintain a more neutral body posture during uniportal VATS by standing straight and facing the monitor with only minimal neck extension/rotation; however, frustration is greater than with triportal VATS.

Analysis of spontaneous pneumothorax in the city of Cuneo: environmental correlations with meteorological and air pollutant variables.

BACKGROUND AND PURPOSE: Primary spontaneous pneumothorax (PSP) tends to cluster. Previous studies have found a correlation between PSP and atmospheric pressure variations or thunderstorms. We conducted this study to analyze the PSP correlations with meteorological variables and the concentrations of air pollutants in the city of Cuneo in Italy (IT). METHODS: We evaluated prospectively 451 consecutive PSP patients treated between 2004 and 2010. For each day within the period analyzed, the meteorological parameters and pollutants data were recorded. Statistical analyses on PSP were done for distribution characteristics, spectral autocorrelation, and spectral analysis. Multivariate regression analyses were performed using artificial neural networks. RESULTS: Analysis of annual, seasonal, and monthly distributions showed no significant correlation between PSP and the time series. The spectral analysis showed that PSP events were not random. Correlations between meteorological and environmental variables confirmed that PSP was significantly more likely to occur on warm windy days with high atmospheric pressure and high mean nitrogen dioxide concentration. CONCLUSIONS: Meteorological parameters and atmospheric pollutants might explain the cluster onset of PSP.