[Variation in ventilatory response to CO2 in patients treated by non-invasive ventilation]. / Variation de la réponse ventilatoire au CO2 chez des patients appareillés par ventilation non invasive.

INTRODUCTION: There are many mechanisms for improving the clinical and blood gas status of patients with the obesity hypoventilation syndrome (OHS) or chronic obstructive pulmonary disease (COPD) by non-invasive ventilation (NIV) at home. Our objective was to set up a pilot study to evaluate the potential modification of the sensitivity of the respiratory centers to CO2 by NIV in paired new COPD and OHS patients. METHODS: We assessed the sensitivity of the respiratory centers to CO2 by the Read method in 3 COPD patients and 3 OHS patients newly treated by NIV and again 3 months later. We compared their results to those of 6 control subjects. RESULTS: All the patients included had altered ventilatory responses to CO2 with slopes of less of than 1 L.min-1.mmHg-1. Mean coefficients of variation were significantly higher in patients than in healthy subjects (P=0.007). Patients who improved their CO2 sensitivity slope were those most observant of NIV. CONCLUSION: This work showed significant changes in the ventilatory response to hypercapnia in patients with either OHS or COPD after NIV therapy. The significance of these changes deserves to be studied.

Diffusing capacity of the lung for CO and pulmonary blood flow during incremental and intermittent exercise.

The aims of this study were to evaluate the feasibility of successive diffusing capacity of the lung for carbon monoxide (DLCO) measurements during two different exercise tests (upright cycling), and to compare the relationships between DLCO and pulmonary blood flow (Qc). Eight healthy subjects performed an incremental test (1-min step) and a strenuous 30-min intermittent-work exercise test (4 min at low and 2 min at high workload). Intrabreath DLCO and Qc were calculated by assessing the uptake of CO and C2H2 during exhalation. DLCO could be measured reliably up to 73-90% of peak oxygen consumption (VO2) during the incremental test, and up to 85-95% of peak VO2 during the intermittent test. The coefficients of variation of DLCO and Qc measured during two successive constant-load exercise tests were 5-6% and 7-11%, respectively. The highest values of DLCO, Qc and VO2 measured during the incremental and intermittent tests were similar (56 and 51 mL/mmHg/min for DLCO, 18.7 and 18.3 L/min, for Qc and 2.4 and 2.3 L/min for VO2, respectively). The main observed result was that the linear relationships between DLCO and Qc were similar whatever the exercise type. This allows DLCO comparisons, with regards to Qc, during different exercise protocols.

[Approaches to the pre-operative functional assessment of patients with lung cancer and preoperative rehabilitation]. / Bilan fonctionnel préopératoire du cancer bronchique et réhabilitation préopératoire.

Surgery is the best treatment for early lung cancer but requires a preoperative functional evaluation to identify patients who may be at a high risk of complications or death. Guideline algorithms include a cardiological evaluation, a cardiopulmonary assessment to calculate the predicted residual lung function, and identify patients needing exercise testing to complete the evaluation. According to most expert opinion, exercise tests have a very high predictive value of complications. However, since the publication of these guidelines, minimally-invasive surgery, sublobar resections, prehabilitation and enhanced recovery after surgery (ERAS) programmes have been developed. Implementation of these techniques and programs is associated with a decrease in postoperative mortality and complications. In addition, the current guidelines and the cut-off values they identified are based on early series of patients, and are designed to select patients before major lung resection (lobectomy-pneumonectomy) performed by thoracotomy. Therefore, after a review of the current guidelines and a brief update on prehabilitation (smoking cessation, exercise training and nutritional aspects), we will discuss the need to redefine functional criteria to select patients who will benefit from lung surgery.

Radiation-induced lung toxicity predictors: Retrospective analysis of 90 patients treated with stereotactic body radiation therapy for stage I non-small-cell lung carcinoma.

BACKGROUND: The main complication after hypofractionated radiotherapy for lung carcinoma is radiation-induced lung toxicity, which can be divided into radiation pneumonitis (acute toxicity, occurring within 6 months) and lung fibrosis (late toxicity, occurring after 6 months). The literature describes several predictive factors related to the patient, to the tumor (volume, central location), to the dosimetry and to biological factors. MATERIALS AND METHODS: This study is a retrospective analysis of 90 patients treated with stereotactic body irradiation for stage I non-small-cell lung carcinoma between December 2010 and May 2015. RESULTS: Radiation pneumonitis was observed in 61.5% of the patients who were mainly asymptomatic (34%). Chronic obstructive pulmonary disease was not predictive of radiation pneumonitis, whereas active smoking was protective. Centrally located tumors were not more likely to result in this complication if the radiation schedule utilized adapted fractionation. In our study, no predictive factor was identified. Whereas the mean lung dose was a predictive factor in 3D radiotherapy, the lung volume irradiated at high doses seemed to be involved in the pathogenesis after hypofractionated radiotherapy. CONCLUSION: The discovery of predictive factors for radiation pneumonitis is difficult due to the rarity of this complication, especially with an 8×7.5Gy schedule. Radiation pneumonitis seems to be correlated with the volume irradiated at high doses, which is in contrast to the known knowledge about the organs in parallel. This finding leads us to raise the hypothesis that vessel damage, organs in series, occurring during hypofractionated radiotherapy could be responsible for this toxicity.

ERS/ESTS clinical guidelines on fitness for radical therapy in lung cancer patients (surgery and chemo-radiotherapy).

A collaboration of multidisciplinary experts on the functional evaluation of lung cancer patients has been facilitated by the European Respiratory Society (ERS) and the European Society of Thoracic Surgery (ESTS), in order to draw up recommendations and provide clinicians with clear, up-to-date guidelines on fitness for surgery and chemo-radiotherapy. The subject was divided into different topics, which were then assigned to at least two experts. The authors searched the literature according to their own strategies, with no central literature review being performed. The draft reports written by the experts on each topic were reviewed, discussed and voted on by the entire expert panel. The evidence supporting each recommendation was summarised, and graded as described by the Scottish Intercollegiate Guidelines Network Grading Review Group. Clinical practice guidelines were generated and finalized in a functional algorithm for risk stratification of the lung resection candidates, emphasising cardiological evaluation, forced expiratory volume in 1 s, systematic carbon monoxide lung diffusion capacity and exercise testing. Contrary to lung resection, for which the scientific evidences are more robust, we were unable to recommend any specific test, cut-off value, or algorithm before chemo-radiotherapy due to the lack of data. We recommend that lung cancer patients should be managed in specialised settings by multidisciplinary teams.

Respiratory sound analysis in the era of evidence-based medicine and the world of medicine 2.0.

OBJECTIVE: This paper describes the state of the art, scientific publications, and ongoing research related to the methods of analysis of respiratory sounds. METHODS AND MATERIAL: Narrative review of the current medical and technological literature using Pubmed and personal experience. RESULTS: We outline the various techniques that are currently being used to collect auscultation sounds and provide a physical description of known pathological sounds for which automatic detection tools have been developed. Modern tools are based on artificial intelligence and techniques such as artificial neural networks, fuzzy systems, and genetic algorithms. CONCLUSION: The next step will consist of finding new markers to increase the efficiency of decision-aiding algorithms and tools.

[Vocal cord dyskinesia and/or asthma]. / Dyskinésie des cordes vocales et/ou asthme.

INTRODUCTION: Vocal cord dyskinesia or vocal cord dysfunction (VCD) is characterized by intermittent abnormal adduction of the vocal cords leading to airflow limitation at the level of the larynx, in the absence of local organic disease. It may occur in isolation or in association with asthma. The pathophysiology is complex and poorly understood. Wheeze, stridor or apparent upper airway obstruction are the most common symptoms. It occurs in a wide age range, more commonly in women, and diagnosis is often delayed and leads to unnecessary treatments (intubation, tracheostomy and high dose steroids). METHODS: A retrospective study of 15 cases of VCD (8 cases of isolated VCD and 7 cases of VCD with associated asthma) describing the main clinical features and the diagnosis strategy. RESULTS: Apparent upper airway obstruction, with or without associated asthma, requires an ear nose and throat examination with laryngoscopy to confirm the paradoxical adduction of the vocal cords during an acute episode of dyspnoea or during a provocation test with triggers like exercise or exposure to irritants, and for the purpose of differential diagnosis. CONCLUSIONS: VCD remains under-appreciated and misdiagnosed, often by mimicking asthma with which it can be associated. A delayed diagnosis by emergency specialists, pulmonologists and ear nose and throat surgeons leads to unnecessary treatments and morbidity before specific therapy can be given.

[Preoperative assessment of lung cancer patients before lung resection]. / L'évaluation cardio-respiratoire avant la chirurgie thoracique du cancer bronchique.

The aim of the functional evaluation of lung cancer patients before lung resection is to evaluate the risk of peri-operative cardio-respiratory complications. The successive steps of the functional assessment are determined according to the predictive value, the invasiveness, and the sophistication of the tests. The cardiovascular risk is evaluated using clinical predictors and ECG findings. If both are negative, the first step of the respiratory function assessment will be FEV1 measurement. Simultaneous measurement of CO diffusing lung capacity (DLCO), which has a high predictive value of complications, is highly recommended by some authors. The second and the third steps will be either exercise testing or split function studies based on quantitative perfusion scan results, the position of the test in the algorithm depending on the authors. Formal exercise testing has been found to be the best predictor of postoperative complications in several studies. However, it does not evaluate the functional contribution of the parenchyma to be resected, which required a perfusion scan. On the other hand, patients with low values of predicted post-operative FEV1 or DLCO should undergo exercise tests. Eventually, clinical, surgical and anesthetic factors should also be taken into account in addition to the functional evaluation to assess the perioperative risk of the patient.

Skeletal muscle response to short endurance training in heart transplant recipients.

OBJECTIVES: We sought to examine the effects of endurance training on the ultrastructural characteristics of skeletal muscle in heart transplant recipients (HTRs) and age-matched control subjects (C). BACKGROUND: Deconditioning is one of the factors involved in the peripheral limitation of exercise capacity of HTRs, and training has proven to be beneficial. METHODS: Biopsies of the vastus lateralis muscle, analyzed by ultrastructural morphometry, and quadriceps muscle cross-sectional area, assessed by computed tomography (CT), were performed in 12 HTRs and 7 age-matched C before and 6 weeks after an endurance training program. Maximal oxygen uptake (peak VO2) was determined by an incremental exercise test. Additionally muscle biopsies were performed before and after a 6-week control period in four HTRs to check for spontaneous improvement. RESULTS: Training resulted in similar increases in peak VO2 (11% in HTRs, 8.5% in C), ventilatory threshold (23% in HTRs, 32% in C) and total endurance work (54% in HTRs, 31% in C). Volume density of total mitochondria increased significantly (26% in HTRs, 33% in C) with a predominant increase of subsarcolemmal mitochondrial volume density (74% in HTRs, 70% in C). The capillary/fiber ratio increased by 19% in C only. In the nontrained group, none of the structural markers was spontaneously modified. CONCLUSIONS: Six weeks of endurance training in HTRs and C led to similar improvements of aerobic work capacity. However, the decreased muscular capillary network in HTRs remained unchanged with training. Immunosuppressive therapy might be responsible for the discrepancy between the normal mitochondrial content and the reduced capillary supply of these patients.

Structure of skeletal muscle in heart transplant recipients.

OBJECTIVES: This study sought to define the ultrastructural characteristics of skeletal muscle in heart transplant recipients (HTRs) in relation to exercise capacity compared with that in age-matched control subjects. BACKGROUND: Muscle structural features seem to play an important role in the limitation of exercise capacity of HTRs long after transplantation. METHODS: The structure of the vastus lateralis muscle was analyzed by ultrastructural morphometry in 16 HTRs and 20 healthy control subjects. Maximal oxygen consumption (peak Vo2) was determined by an incremental exercise test. RESULTS: Peak Vo2 was significantly lower (by 35%) in HTRs. Fiber size, volume density of mitochondria and intramyocellular lipid deposits were not significantly different between HTRs and control subjects. In contrast, the capillary density and the capillary/fiber ratio were both significantly reduced in HTRs (by 24% and 27%, respectively). CONCLUSIONS: A normal volume density of mitochondria and a reduced capillary network are the main characteristics of muscle ultrastructure in HTRs by 10 months after transplantation. The muscle structural abnormalities and reduced exercise capacity might be related to immunosuppressive therapy with cyclosporine and corticosteroids as well as deconditioning.

Oscillations in sympatho-vagal balance oppose variations in delta-wave activity and the associated renin release.

To determine the potential role of the sympathetic nervous system in the generation of the oscillations in PRA over the 24-h period, we used the autocorrelation coefficient of RR interval (rRR), a new tool to evaluate the sympatho-vagal balance continuously. We determined the influence of the sympathetic nervous system both on the nocturnal PRA oscillations associated to increases in delta-wave activity and on the daytime oscillations that occur randomly in awake subjects. PRA and rRR were determined every 10 min during 24 h in nine healthy subjects under continuous bed rest. Electroencephalographic spectral analysis was used to establish the variations in delta-wave activity during sleep, from 2300-0700 h. The overnight profiles in PRA, rRR and delta-wave activity were analyzed using a modified version of the pulse detection program ULTRA. The temporal link among the profiles of rRR, PRA, and delta-wave activity was quantified using cross-correlation analysis. During sleep, large oscillations in PRA were strongly linked to variations in delta-wave activity. They were preceded by opposite oscillations in rRR, decreases in rRR reflecting predominant vagal activity, and increases in rRR reflecting sympathetic dominance. During the waking periods, the levels of rRR were higher, with smaller variations. The daytime PRA oscillations were not associated with any significant changes in rRR, and conversely, significant oscillations in rRR were not followed by any significant changes in PRA. In conclusion, the sympathetic nervous system is not directly involved in the generation of renin oscillations observed under basal conditions. During sleep, the oscillations in sympatho-vagal balance are inversely related to the variations in delta-wave activity and the associated renin release. The processes that give the intermittent signal for concomitant increases in slow wave activity and renin release from the kidney remain to be identified.

Exercise-induced increase in circulating adrenomedullin is related to mean blood pressure in heart transplant recipients.

Adrenomedullin (ADM) is a newly discovered potent vasorelaxing and natriuretic peptide that recently has been shown to be increased after heart transplantation. To investigate the hemodynamic factors modulating its release and the eventual role of ADM in blood pressure regulation after heart transplantation, seven matched heart-transplant recipients (Htx) and seven normal subjects performed a maximal bicycle exercise test while monitoring for heart rate, blood pressure, and circulating ADM. Baseline heart rate and systemic blood pressure were higher in Htx; left ventricular mass index and ADM tended to be higher after heart transplantation and correlated positively in Htx (r = 0.79, P = 0.03). As expected, exercise-induced increase in heart rate was lower in Htx than in controls (60 +/- 11 % vs. 121 +/- 14 %, respectively) and blood pressure increase was similar in both groups. Maximal exercise increased significantly plasma ADM in both groups (from 25.3 +/- 3.1 to 30.7 +/- 3.5 pmol/L, P < 0.05 and from 15.2 +/- 1.4 to 29.1 +/- 4.4 pmol/L, P = 0.02 in Htx and controls, respectively), the hypotensive peptide level remaining elevated until the 30th min of recovery. A significant inverse relationship was observed between peak mean blood pressure and circulating ADM in Htx (r = -0.86, P < 0.02). Besides showing that circulating ADM is increased after heart transplantation, the present study demonstrates a positive relationship between baseline ADM and left ventricular mass index. Furthermore, maximal exercise-induced increase in ADM is inversely related to mean blood pressure in Htx, suggesting that ADM might participate in blood pressure regulation during exercise after heart transplantation.

Inability of serum neuron-specific enolase to predict disease extent in small cell lung cancer.

Serum neuron-specific enolase (NSE) levels were measured before treatment in 112 patients diagnosed as having small cell lung cancer in our department. All these patients underwent exhaustive staging procedures: 53 had limited disease (LD) and 59 extensive disease (ED). Serum NSE was elevated in 83% of the patients (i.e. 71% of the patients with LD and 93% of the patients with ED). Mean values of NSE differed significantly according to disease extent. A receiver-operating characteristic curve was constructed with different cut-off levels of serum NSE in order to determine the accuracy of NSE for identifying ED. There was no level of NSE capable of predicting with sufficient accuracy the presence of ED. The best compromise was given by a threshold of 35 micrograms/l: 60% of the ED patients had a serum NSE above 35 micrograms/l but 30% of the LD patients also had a serum NSE above 35 micrograms/l.

Early alternating chemotherapy and radiotherapy schedule in limited disease stage small cell lung cancer.

44 patients with limited small cell lung cancer were treated with six cycles of chemotherapy (cisplatinum 60 mg/m2 day 1, doxorubicin 40 mg/m2 day 1, etoposide 100 mg/m2 days 1-3) alternating with three courses of mediastinal irradiation, the first one starting 7 days after the first day of chemotherapy. A total dose of 55 Gy was delivered. Prophylactic cranial irradiation (30 Gy after the third cycle of chemotherapy) was left to the physician's discretion. 4 patients had radical surgery before combined modality treatment. 29 patients finished the scheduled program. The complete response rate (bronchoscopically confirmed) was 25.6% after two cycles of chemotherapy and 41% at the end of treatment. Median survival time was 17.2 months, with an estimated survival of 32% at 2 years. Main toxicity was haematological with one early toxic death and six premature interruptions of treatment. We conclude that this treatment modality is feasible and efficacious. Prospective studies comparing chemotherapy with alternating or concurrent early radiotherapy schedules in limited disease small cell lung cancer are needed to determine the best treatment modality.

The concept of Raynaud's phenomenon of the lung revisited.

PURPOSE: Having observed that a cold pressor test (CPT) induces a decrease in carbon monoxide single breath diffusing capacity (DLco) in normal subjects contrary to the findings of Fahey et al (Am J Med. 1984; 76:263-269), we compared the response to CPT for the two types of Raynaud's phenomenon. PATIENTS: Two groups of 8 patients suffering from primary or secondary Raynaud's phenomenon were examined. METHODS: Single breath diffusing capacity, mean pulmonary artery pressure (PAP), cardiac output (CO), pulmonary capillary wedge pressure (PwP), and pulmonary vascular resistance (PVR) were measured before and 30 minutes after CPT, which consisted of immersing both hands in a water bath at 12 degrees C for 2 minutes. RESULTS: Cold pressor testing induced no change in DLco or cardiovascular parameters in patients with secondary Raynaud's phenomenon. Conversely, in patients with the primary form, it induced a significant decrease in DLco (16%), PAP (20%), and PVR (27%), whereas CO and PwP remained unaltered. CONCLUSIONS: The concept of pulmonary Raynaud's phenomenon had to be reconsidered, as it is also observed in normal subjects, and is due to a vasodilatation and not to a vasoconstriction of the pulmonary artery (Frans et al, J Appl Physiol. 1994; 76:750-755). In patients with primary Raynaud's phenomenon, the decrease in DLco is not only a physiological response, but a pathological response to a CPT, as it is significantly more marked in patients than in control subjects (16% versus 10% for controls, same reference). The contribution by Fahey et al remains important, however, in that it allows assessing whether a patient with Raynaud's phenomenon suffers from the primary or secondary form of the disease.

A phase II trial of radiochemotherapy with daily carboplatin, after induction chemotherapy (carboplatin and etoposide), in locally advanced nonsmall-cell lung cancer: final analysis.

PURPOSE: To evaluate feasibility and efficacy of concomitant radiochemotherapy (CRCT) in Stage IIIB nonsmall-cell lung cancer (NSCLC), two induction chemotherapy cycles combining etoposide and carboplatin were first delivered, followed by CRCT with daily radiation fraction in association with carboplatin. METHODS AND MATERIALS: Forty patients with biopsy-proven, locally advanced unresectable nonmetastatic NSCLC were enrolled. Induction chemotherapy consisted of two cycles (day 1 and day 28) of etoposide (VP16:100 mg/m2, days 1 to 3) and carboplatin (CBDCA:350 mg/m2, day 1). Irradiation starting at day 56, delivered 66 Gy in 2 Gy daily fraction, 5 days a week, along with a daily dose of CBDCA (15 mg/m2) given intravenously 2 to 4 h before radiation. In nonprogressive patients under induction chemotherapy, two additional cycles of VP16-CBDCA were administered 4 weeks after the completion of CRCT. RESULTS: Out of the 40 patients enrolled (38 males, 2 females), 37 (93%) received induction chemotherapy as scheduled, with 38% Grade 3-4 hematological toxicity. Response rate to induction chemotherapy was 11% (4/37). No tumor became resectable. CRCT was delivered to 32 of these 37 patients, with full doses given to 91% of them. Clinical and hematological Grade 3-4 toxicity rates were 21 and 13%, respectively. Additional chemotherapy was delivered in 12 of 26 nonprogressive patients. At final evaluation, performed 3 months after the end of CRCT, 38% of 26 evaluable patients were responders (4 complete and 6 partial), leading to a 25% (10 of 40) overall objective response rate. Of these 10 responders, 8 became responders after CRCT only. Overall, the 1-year local control rate was 28% (11 of 40). The median survival time was 9 months and the 1-year and 2-year overall survival rates were 38 and 15%, respectively. Thirty-six patients died from local progression (25 patients), distant metastasis (9 patients), or pulmonary fibrosis (2 patients). CONCLUSION: Concomitant CRCT with CBDCA is feasible with acceptable induction chemotherapy-related toxicity and a 1-year local control rate of 28%. Response rate to induction chemotherapy was low and better chemotherapy combination should be used to reduce distant failure probability and to improve local response rate before CRCT.

Lung membrane diffusing capacity, heart failure, and heart transplantation.

The pulmonary diffusing capacity for carbon monoxide (DLCO) is reduced in chronic heart failure and remains decreased after heart transplantation. This decrease in DLCO may depend on a permanent alteration after transplantation of one or the other of its components: diffusion of the alveolar capillary membrane or the pulmonary capillary blood volume (Vc). Therefore, we measured DLCO, the membrane conductance, and Vc before and after heart transplantation. At the time of hemodynamic measurements, the Roughton and Forster method of measuring DLCO at varying alveolar oxygen concentrations was used to determine the membrane conductance, Vc, DLCO/alveolar volume (VA), the membrane conductance/VA and thetaVc/VA (theta = carbon monoxide conductance of blood, VA = alveolar volume) in 21 patients with class III to IV heart failure before and after transplantation, and in 21 healthy controls. Transplantation normalized pulmonary capillary pressure and increased cardiac index. DLCO was decreased before transplantation (7.11 vs 10.0 mmol/min/kPa in controls), but DLCO/VA was normal (1.67+/-0.44 vs 1.71+/-0.26 mmol/min/kPa/L in controls). DLCO/VA remained unchanged after transplantation, because the decrease in Vc (82+/-30 vs 65+/-18 ml before and after transplantation) and thetaVc/VA was not compensated by the changes in membrane conductance (11+/-4 vs 12+/-5 mmol/min/kPa before and after transplantation, respectively) and membrane conductance/VA. We conclude that the decrease in DLCO in patients with chronic heart failure is due to a restrictive ventilatory pattern because their DLCO/VA remains normal; the decrease in the membrane conductance is compensated by the increase in Vc. After transplantation, the decrease in Vc due to normalization of pulmonary hemodynamics is not completely compensated for by an increase in membrane conductance. Because the membrane conductances, measured before and after transplantation, are negatively correlated with duration of heart failure, its abnormal pulmonary hemodynamics may have irreversibly altered the alveolar capillary membrane.

Prognostic value of histology in patients with non-small cell lung cancer.

To evaluate the impact of non-small cell lung cancer (NSCLC) histological subtypes on survival, we performed a retrospective multivariate analysis of survival in 361 patients with a NSCLC diagnosed in 1987 and 1988 at the University Hospital in Strasbourg, France. There were 262 (73%) squamous cell carcinomas (SQ), 59 (16%) adenocarcinomas other than bronchioloalveolar carcinoma (ADOBAC), 24 (7%) bronchioloalveolar carcinoma (BAC) and 16 (4%) large cell carcinomas (LC). The proportion of metastatic disease was significantly higher in the ADOBAC group than in the SQ group (30% vs. 15%, P < 0.001). In operated patients, only extent of disease and age were independent prognostic factors. In patients with unresectable NSCLC, extent of disease had also the heaviest impact on survival. However, in these unresected patients, ADOBAC had a pejorative impact on survival, in contrast to BAC which was of better prognosis. If these results are confirmed by prospective studies, this will support stratification according to histological subtypes in clinical trials involving inoperable NSCLC patients.

International differences in epidemiology of lung adenocarcinoma.

In Europe, the squamous cell carcinoma is the most frequent non-small cell lung cancer (NSCLC) subtype and until now, no increase in incidence of lung adenocarcinoma (ADC) has been described (except in the Netherlands), in contrast to North America where ADC predominates. Our aim was to compare the percentage of ADC in Montreal (MTL), Canada, with that in Strasbourg (STBG), France. We prospectively identified patients with NSCLC in MTL and in STBG over an 8-month period and described the distribution of NSCLC by sex, age, subtype and smoking history. A total of 172 patients in MTL and 166 in STBG were identified. The male/female ratio was significantly different in STBG (12:1) and in MTL (2:1). The percentage of ADC was significantly higher in MTL (40%) than in STBG (30%). This difference is partly due to the higher number of women with NSCLC in Montreal combined with the predominance of ADC in women. The proportion of ADC decreased with age in STBG, but was similar in each age category in MTL. In STBG, most women with NSCLC had never smoked (69%), in contrast to MTL where only 16% of women had never smoked. In conclusion, ADC is more frequent in MTL than in STBG. This is partly due to the higher number of women with NSCLC in MTL combined with the predominance of ADC in women. The greatest proportion of ADC subtype in the youngest cohorts of men in STBG suggests that ADC may be on the rise in this city.