Impact of interstitial lung abnormalities on postoperative pulmonary complications and survival of lung cancer.

BACKGROUND: Interstitial lung abnormalities (ILAs) are associated with the risk of lung cancer and its mortality. However, the impact of ILA on treatment-related complications and survival in patients who underwent curative surgery is still unknown. RESEARCH QUESTION: This study aimed to evaluate the significance of the presence of computed tomography-diagnosed ILA and histopathologically matched interstitial abnormalities on postoperative pulmonary complications (PPCs) and the long-term survival of patients who underwent surgical treatment for lung cancer. STUDY DESIGN AND METHODS: A matched case-control study was designed to compare PPCs and mortality among 50 patients with ILA, 50 patients with idiopathic pulmonary fibrosis (IPF) and 200 controls. Cases and controls were matched by sex, age, smoking history, tumour location, the extent of surgery, tumour histology and pathological TNM stage. RESULTS: Compared with the control group, the OR of the prevalence of PPCs increased to 9.56 (95% CI 2.85 to 32.1, p<0.001) in the ILA group and 56.50 (95% CI 17.92 to 178.1, p<0.001) in the IPF group. The 5-year overall survival (OS) rates of the control, ILA and IPF groups were 76% (95% CI 71% to 83%), 52% (95% CI 37% to 74%) and 32% (95% CI 19% to 53%), respectively (log-rank p<0.001). Patients with ILA had better 5-year OS than those with IPF (log-rank p=0.046) but had worse 5-year OS than those in the control group (log-rank p=0.002). CONCLUSIONS: The presence of radiological and pathological features of ILA in patients with lung cancer undergoing curative surgery was associated with frequent complications and decreased survival.

Preoperative Helical Dynamic Enhanced Multidetector Row Computed Tomography: Can It Be a Prognostic Indicator in Early-Stage Non-small Cell Lung Cancer?

OBJECTIVE: This study aimed to investigate the prognostic significance of dynamic contrast-enhanced computed tomography in patients with stage IA non-small cell lung cancer (NSCLC). METHODS: We retrospectively enrolled 139 patients (77 men, 62 women; mean age, 59 years) with stage IA NSCLC who underwent dynamic contrast-enhanced computed tomography. Data on age, pathologic subtype, peak enhancement, and net enhancement of primary lung cancer were collected and correlated with 5-year survival. RESULTS: Peak enhancement had a significant correlation with overall survival in the univariable analysis (hazard ratio [HR], 1.18, confidence interval [CI], 1.01-1.38; P = 0.04) and in the multivariable analysis (HR, 1.19; CI, 1.01-1.39; P = 0.04). Patients with peak enhancement of 90 Hounsfield unit or higher had a significantly increased risk of death compared with patients with less enhancement after curative surgery (HR, 4.15; CI, 1.23-13.95; P = 0.02). CONCLUSIONS: Our study confirmed the prognostic significance of peak enhancement as an indicator for the overall survival of stage IA NSCLC.

The Higher Incidence of COVID-19 in Patients With Non-Tuberculous Mycobacterial Pulmonary Disease: A Single Center Experience in Korea.

The aim of our study was to investigate the incidence of and risk factors for coronavirus disease 2019 (COVID-19) in patients with non-tuberculous mycobacterial-pulmonary disease (NTM-PD). A total of 3,866 patients with NTM-PD were retrospectively identified from a single center. Compared to the general population of Korea, patients with NTM-PD had a substantially increased age-standardized incidence of COVID-19 from January 2020 to February 2021 (2.1% vs. 0.2%). The odds of being infected with COVID-19 was particularly higher in patients who received treatment for NTM-PD than in those who did not receive treatment for NTM-PD (adjusted odd ratio = 1.99, 95% confidence interval = 1.09-3.64, P = 0.026). Patients with NTM-PD might be regarded as a high-risk group for COVID-19 and may need a more proactive preventive strategy for COVID-19 and other pandemics in the future.

Chronic obstructive pulmonary disease and lung cancer incidence in never smokers: a cohort study.

There has been limited evidence for the association between chronic obstructive pulmonary disease (COPD) and the incidence of lung cancer among never smokers. We aimed to estimate the risk of lung cancer incidence in never smokers with COPD, and to compare it with the risk associated with smoking. This cohort study involved 338 548 subjects, 40 to 84 years of age with no history of lung cancer at baseline, enrolled in the National Health Insurance Service National Sample Cohort. During 2 355 005 person-years of follow-up (median follow-up 7.0 years), 1834 participants developed lung cancer. Compared with never smokers without COPD, the fully-adjusted hazard ratios (95% CI) for lung cancer in never smokers with COPD, ever smokers without COPD, and ever smokers with COPD were 2.67 (2.09 to 3.40), 1.97 (1.75 to 2.21), and 6.19 (5.04 to 7.61), respectively. In this large national cohort study, COPD was also a strong independent risk factor for lung cancer incidence in never smokers, implying that COPD patients are at high risk of lung cancer, irrespective of smoking status.

Prognostic factors associated with long-term mortality in 1445 patients with nontuberculous mycobacterial pulmonary disease: a 15-year follow-up study.

Limited data are available regarding the prognostic factors for patients with nontuberculous mycobacterial pulmonary disease (NTM-PD). We investigated the prognostic factors associated with long-term mortality in NTM-PD patients after adjusting for individual confounders, including aetiological organism and radiological form.A total of 1445 patients with treatment-naïve NTM-PD who were newly diagnosed between July 1997 and December 2013 were included. The aetiological organisms were as follows: Mycobacterium avium (n=655), M. intracellulare (n=487), M. abscessus (n=129) and M. massiliense (n=174). The factors associated with mortality in NTM-PD patients were analysed using a multivariable Cox model after adjusting for demographic, radiological and aetiological data.The overall 5-, 10- and 15-year cumulative mortality rates for the NTM-PD patients were 12.4%, 24.0% and 36.4%, respectively. On multivariable analysis, the following factors were significantly associated with mortality in NTM-PD patients: old age, male sex, low body mass index, chronic pulmonary aspergillosis, pulmonary or extrapulmonary malignancy, chronic heart or liver disease and erythrocyte sedimentation rate. The aetiological organism was also significantly associated with mortality: M. intracellulare had an adjusted hazard ratio (aHR) of 1.40, 95% CI 1.03-1.91; M. abscessus had an aHR of 2.19, 95% CI 1.36-3.51; and M. massiliense had an aHR of 0.99, 95% CI 0.61-1.64, compared to M. avium Mortality was also significantly associated with the radiological form of NTM-PD for the cavitary nodular bronchiectatic form (aHR 1.70, 95% CI 1.12-2.59) and the fibrocavitary form (aHR 2.12, 95% CI 1.57-3.08), compared to the non-cavitary nodular bronchiectatic form.Long-term mortality in patients with NTM-PD was significantly associated with the aetiological NTM organism, cavitary disease and certain demographic characteristics.

Species Distribution and Macrolide Susceptibility of Mycobacterium fortuitum Complex Clinical Isolates.

The understanding of species distribution and inducible macrolide resistance in the Mycobacterium fortuitum complex (MFC) is limited. Of 90 mostly respiratory MFC clinical isolates, half were M. fortuitum, followed by M. peregrinum, M. porcinum, M. septicum, and M. conceptionense Most M. fortuitum, M. porcinum, and M. septicum isolates were inducibly resistant to clarithromycin, whereas two-thirds of the M. peregrinum isolates were clarithromycin susceptible. Clarithromycin-resistant M. fortuitum isolates exhibited common mutations of erm(39), potentially involved in clarithromycin resistance.

In Vitro Activity of Bedaquiline and Delamanid against Nontuberculous Mycobacteria, Including Macrolide-Resistant Clinical Isolates.

We evaluated the in vitro activities of the antimicrobial drugs bedaquiline and delamanid against the major pathogenic nontuberculous mycobacteria (NTM). Delamanid showed high MIC values for all NTM except Mycobacterium kansasii However, bedaquiline showed low MIC values for the major pathogenic NTM, including Mycobacterium avium complex, Mycobacterium abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. kansasii Bedaquiline also had low MIC values with macrolide-resistant NTM strains and warrants further investigation as a potential antibiotic for NTM treatment.

Clinical usefulness of routine AFB culture and MTB PCR of EBUS-TBNA needle rinse fluid.

BACKGROUND AND OBJECTIVE: We evaluated the usefulness of acid-fast bacilli (AFB) culture and Mycobacterium tuberculosis (MTB) polymerase chain reaction (PCR) of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) needle rinse fluid for diagnosing tuberculous lymphadenitis. METHODS: EBUS-TBNA needle rinse fluid was routinely used for AFB culture and MTB PCR. The patients were categorized according to the pre-procedural diagnosis (Group A, suspected/histology-confirmed lung cancer; Group B, extrapulmonary malignancy; and Group C, other benign diseases). RESULTS: Of the 4672 subjects, 104 (2.2%) were diagnosed with tuberculous lymphadenitis; 1.0%, 4.6% and 12.7% of Group A, B and C, respectively. Tuberculous lymphadenitis was diagnosed in 0.2%, 1.0% and 4.5% Group A, B and C patients, respectively, by histopathology. On addition of AFB culture to histopathology, tuberculous lymphadenitis was diagnosed in 1.0%, 4.4% and 10.3% of Group A, B and C patients, respectively (P < 0.001, P = 0.001 and P = 0.005, respectively). On addition of MTB PCR to histopathology, tuberculous lymphadenitis was diagnosed in 0.4%, 1.9% and 8.8%, respectively (Group C; P = 0.029). CONCLUSION: Routine AFB culture of needle rinse fluid was useful to increase the diagnostic yield of tuberculous lymphadenitis for all subjects who underwent EBUS-TBNA regardless of pre-procedural diagnosis in an intermediate tuberculosis (TB)-burden country. However, MTB PCR was only useful in subjects with pre-procedural diagnosis of benign pulmonary diseases.

Development of Macrolide Resistance and Reinfection in Refractory Mycobacterium avium Complex Lung Disease.

RATIONALE: Patients with refractory Mycobacterium avium complex lung disease (MAC-LD) undergo long-term macrolide therapy, but macrolide resistance develops infrequently. OBJECTIVES: The aim of this study was to determine whether reinfection was a factor in the low incidence of macrolide resistance in patients with refractory MAC-LD. METHODS: Among 481 patients with treatment-naive MAC-LD who started antibiotic treatment between January 2002 and December 2013, we identified 72 patients with refractory disease, characterized by persistently positive sputum cultures despite ≥12 months of treatment. Molecular analyses of the 23S ribosomal RNA gene responsible for macrolide resistance and serial mycobacterial genotyping were performed using stored MAC isolates. MEASUREMENTS AND MAIN RESULTS: The median duration of treatment was 32 months (interquartile range, 24-41 mo) in 72 patients. After treatment for a median of 33 months (interquartile range, 21-44 mo), macrolide resistance developed in 16 (22%) patients. Molecular analysis of isolates from 15 patients revealed that 80% (12 of 15) had a point mutation at position 2,058 or 2,059 of the 23S ribosomal RNA gene. Of the 49 patients who had stored pre- and post-treatment isolates, mycobacterial genotyping revealed that reinfection by new MAC strains occurred in 36 (73%) patients. New MAC strains were found in 24 (49%) patients, and mixed infections with original and new strains occurred in 12 (24%) patients. Only 13 (27%) patients had persistent infections with their original MAC strains. CONCLUSIONS: Refractory MAC-LD is commonly caused by reinfection with new strains rather than persistence of the original strain, which may explain the infrequent development of macrolide resistance in refractory MAC-LD. Clinical trial registered with www.clinicaltrials.gov (NCT00970801).

Risk factors and clinical characteristics of lung cancer in idiopathic pulmonary fibrosis: a retrospective cohort study.

BACKGROUND: Lung cancer is a common comorbidity of idiopathic pulmonary fibrosis (IPF) and has poor outcomes. The incidence and clinical factors related to development of lung cancer in idiopathic pulmonary fibrosis (IPF) are unclear. The aim of this study was to elucidate the cumulative incidence, risk factors, and clinical characteristics of lung cancer in IPF. METHODS: In this retrospective study, we analyzed clinical data for 938 patients who were diagnosed with IPF without lung cancer between 1998 and 2013. Demographic, physiologic, radiographic, and histologic characteristics were reviewed. Cumulative incidence of lung cancer and survival were estimated by the Kaplan-Meier method. Risk factors of lung cancer development were determined by Cox proportional hazard analysis. RESULTS: Among 938 IPF patients without lung cancer at initial diagnosis, lung cancer developed in 135 (14.5%) during the follow-up period. The cumulative incidences of lung cancer were 1.1% at 1 year, 8.7% at 3, 15.9% at 5, and 31.1% at 10 years. Risk factors of lung cancer were male gender, current smoking at IPF diagnosis, and rapid annual decline of 10% or more in forced vital capacity (FVC). Patients who developed lung cancer were mostly elderly men with smoking history. Squamous cell carcinoma followed by adenocarcinoma was the most common histologic type. Lung cancer was frequently located in areas abutting or within fibrosis. Survival was significantly worse in patients with lung cancer compared to patients with IPF alone. CONCLUSION: Lung cancer frequently developed in patients with IPF and was common in current-smoking men with rapid decline of FVC.

Limited Effect of Later-Generation Fluoroquinolones in the Treatment of Ofloxacin-Resistant and Moxifloxacin-Susceptible Multidrug-Resistant Tuberculosis.

Recent data conflict on the clinical efficacy of later-generation fluoroquinolones, such as moxifloxacin or levofloxacin, for the treatment of multidrug-resistant tuberculosis (MDR-TB) that is resistant to ofloxacin but susceptible to moxifloxacin. The purpose of the present study was to evaluate whether later-generation fluoroquinolones can improve treatment outcomes in patients with ofloxacin-resistant, moxifloxacin-susceptible MDR-TB. A retrospective cohort study was performed on 208 patients with moxifloxacin-susceptible MDR-TB who were treated between 2006 and 2011. Later-generation fluoroquinolones were used for all patients. Overall, 171 patients (82%) had ofloxacin-susceptible, moxifloxacin-susceptible MDR-TB (ofloxacin-susceptible group), and 37 (18%) had ofloxacin-resistant, moxifloxacin-susceptible MDR-TB (ofloxacin-resistant group). Compared to the ofloxacin-susceptible group, the ofloxacin-resistant group was more likely to have a history of MDR-TB treatment (P < 0.001) and cavitary lesions on chest radiography (P < 0.001). In addition, the ofloxacin-resistant group was more likely than the ofloxacin-susceptible group to have resistance to the drugs pyrazinamide (P = 0.003), streptomycin (P = 0.015), prothionamide (P < 0.001), and para-aminosalicylic acid (P < 0.001). Favorable outcomes were more frequently achieved for the ofloxacin-susceptible group than for the ofloxacin-resistant group (91% [156/171] versus 57% [21/37], respectively [P < 0.001]). In multivariable regression logistic analysis, the ofloxacin-susceptible group was about 5.36 (95% confidence interval, 1.55 to 18.53) times more likely than the ofloxacin-resistant group (P < 0.001) to have favorable outcomes. Despite in vitro moxifloxacin susceptibility, the frequency of favorable treatment outcomes for ofloxacin-resistant MDR-TB was significantly lower than that for ofloxacin-susceptible MDR-TB, even when later-generation fluoroquinolones were used, indicating that more-aggressive therapies may be needed for ofloxacin-resistant MDR-TB.

Amikacin Inhalation as Salvage Therapy for Refractory Nontuberculous Mycobacterial Lung Disease.

Although guidelines recommend amikacin (AMK) inhalation therapy for difficult-to-treat nontuberculous mycobacterial lung disease (NTM-LD), data are limited regarding the safety and clinical efficacy of this salvage therapy. We retrospectively evaluated the treatment outcomes of 77 patients with refractory NTM-LD caused by Mycobacterium abscessus complex (MABC) or M. avium complex (MAC) who initiated AMK inhalation therapy between February 2015 and June 2016. MABC was the most common etiology (n = 48, 62%), followed by MAC (n = 20, 26%) and mixed infections (n = 9, 12%). Isolates with macrolide resistance and baseline AMK resistance were identified in 63 (82%) patients and 5 (6%) patients, respectively. At 12 months after AMK inhalation therapy, 49% of patients had symptomatic improvement, whereas 42% had radiological improvement. Conversion to a negative sputum culture occurred in 14 (18%) patients, and the culture conversion rate was higher in patients infected with macrolide-susceptible isolates (7/14, 50%) than in those infected with macrolide-resistant isolates (7/63, 11%) (P = 0.003). Significant decreases in sputum semiquantitative culture positivity occurred after AMK inhalation therapy (P < 0.001). On multivariate analysis, conversion to a negative sputum culture was associated with mixed infections (P = 0.009), a forced expiratory volume in 1 s of greater than 60% (P = 0.008), and the absence of macrolide resistance (P = 0.003). Thirty-eight percent of patients experienced adverse effects, with ototoxicity (n = 15) being the most common. AMK inhalation salvage therapy may improve the treatment responses in some patients with refractory NTM-LD. However, considering the common adverse effects, further evaluation of the optimal dosage and intervals for AMK inhalation therapy is needed.

Intermittent Antibiotic Therapy for Recurrent Nodular Bronchiectatic Mycobacterium avium Complex Lung Disease.

Intermittent, three-times-weekly oral antibiotic therapy is recommended for the initial treatment of noncavitary nodular bronchiectatic (NB) Mycobacterium avium complex (MAC) lung disease. However, intermittent therapy is not recommended for patients who have been previously treated. We evaluated 53 patients with recurrent noncavitary NB MAC lung disease who underwent antibiotic treatment for ≥12 months with daily therapy (n = 26) or intermittent therapy (n = 27) between January 2008 and December 2015. Baseline characteristics were comparable between daily therapy and intermittent therapy groups. Sputum culture conversion rates did not differ between daily therapy (21/26, 81%) and intermittent therapy (22/27, 82%) groups. Compared to the etiologic organism at the time of previous treatment, recurrent MAC lung disease was caused by the same MAC species in 38 patients (72%) and by a different MAC species in 15 patients (28%). Genotype analysis in patients with sequenced paired isolates revealed that 86% (12/14) of cases with same species recurrence were due to reinfection with a new MAC genotype. In conclusion, most recurrent noncavitary NB MAC lung disease cases were caused by reinfection rather than relapse. Intermittent antibiotic therapy is a reasonable treatment strategy for recurrent noncavitary NB MAC lung disease.

Mutations in gyrA and gyrB in Moxifloxacin-Resistant Mycobacterium avium Complex and Mycobacterium abscessus Complex Clinical Isolates.

Data on the frequency of gyrA and gyrB mutations in fluoroquinolone-resistant isolates of the Mycobacterium avium complex (MAC) and the Mycobacterium abscessus complex (MABC) are limited. In our analysis, we did not find any resistance-associated mutations in gyrA or gyrB in 105 MAC or MABC clinical isolates, including 72 moxifloxacin-resistant isolates. Our findings suggest that mechanisms other than gyrA and gyrB mutations contribute to moxifloxacin resistance in these organisms.

Changing Epidemiology of Nontuberculous Mycobacterial Lung Diseases in a Tertiary Referral Hospital in Korea between 2001 and 2015.

This study investigated the changes in the major etiologic organisms and clinical phenotypes of nontuberculous mycobacterial lung disease (NTM-LD) over a recent 15-year period in Korea. The increase of number of patients with NTM-LD was primarily due to an increase of Mycobacterium avium complex (MAC) lung disease (LD). Among MAC cases, the proportion of M. avium increased compared with M. intracellulare, whereas the incidence of M. abscessus complex and M. kansasii LD remained relatively stable. The proportion of cases of the nodular bronchiectatic form increased compared with the fibrocavitary form of NTM-LD.

Mycobacterial Characteristics and Treatment Outcomes in Mycobacterium abscessus Lung Disease.

BACKGROUND: Treatment outcomes of patients with Mycobacterium abscessus subspecies abscessus lung disease are poor, and the microbial characteristics associated with treatment outcomes have not been studied systematically. The purpose of this study was to identify associations between microbial characteristics and treatment outcomes in patients with M. abscessus lung disease. METHODS: Sixty-seven consecutive patients with M. abscessus lung disease undergoing antibiotic treatment for ≥12 months between January 2002 and December 2012 were included. Morphotypic and genetic analyses were performed on isolates from 44 patients. RESULTS: Final sputum conversion to culture negative occurred in 34 (51%) patients. Compared to isolates from 24 patients with persistently positive cultures, pretreatment isolates from 20 patients with final negative conversion were more likely to exhibit smooth colonies (9/20, 45% vs 2/24, 8%; P = .020), susceptibility to clarithromycin (7/20, 35% vs 1/24, 4%; P = .015), and be of the C28 sequevar with regard to the erm(41) gene (6/20, 30% vs 1/24, 4%; P = .035). Mycobacterium abscessus lung disease recurred in 5 (15%) patients after successful completion of antibiotic therapy. Genotypic analysis revealed that most episodes (22/24, 92%) of persistently positive cultures during antibiotic treatment and all cases of microbiologic recurrence after treatment completion were caused by different M. abscessus genotypes within a patient. CONCLUSIONS: Precise identification to the subspecies level and analysis of mycobacterial characteristics could help predict treatment outcomes in patients with M. abscessus lung disease. Treatment failures and recurrences are frequently associated with multiple genotypes, suggesting reinfection. CLINICAL TRIALS REGISTRATION: NCT00970801.

Outcomes of Mycobacterium avium complex lung disease based on clinical phenotype.

The effect of the clinical phenotype of Mycobacterium avium complex (MAC) lung disease on treatment outcome and redevelopment of nontuberculous mycobacterial (NTM) lung disease after treatment completion has not been studied systematically.We evaluated 481 treatment-naïve patients with MAC lung disease who underwent antibiotic treatment for ≥12 months between January 2002 and December 2013.Out of 481 patients, 278 (58%) had noncavitary nodular bronchiectatic (NB) disease, 80 (17%) had cavitary NB disease and 123 (25%) had fibrocavitary disease. Favourable outcome was higher in patients with noncavitary disease (88%) than in patients with cavitary disease (76% for fibrocavitary and 78% for cavitary NB disease; p<0.05). Cavitary disease was independently associated with unfavourable outcomes (p<0.05). Out of 402 patients with favourable outcomes, 118 (29%) experienced redevelopment of NTM lung disease, with the same MAC species recurring in 65 (55%) patients. The NB form was an independent risk factor for redevelopment of NTM lung disease (p<0.05). In patients with recurrent MAC lung disease due to the same species, bacterial genotyping revealed that 74% of cases were attributable to reinfection and 26% to relapse.Treatment outcomes and redevelopment of NTM lung disease after treatment completion differed by clinical phenotype of MAC lung disease.

Joint effect of airflow limitation and emphysema on postoperative outcomes in early-stage nonsmall cell lung cancer.

This study aims to evaluate the joint effect of severity of airflow limitation and emphysema on postoperative pulmonary complications (PPCs) and overall survival after complete resection in patients with early-stage nonsmall cell lung cancer (NSCLC).We retrospectively studied 413 male patients with pathologic stage I or II NSCLC between 2007 and 2009. Severity of airflow limitation was defined based on forced expiratory volume in 1 s. Emphysema was defined by ≥5% low attenuation area at -950 HU.In multivariable-adjusted analyses, the adjusted odds ratio (aOR) for any PPC, comparing patients with moderate-to-severe airflow limitation to those without airflow limitation, was 2.23, and the aOR comparing patients with emphysema to those without emphysema was 1.77. However, the joint effect of airflow limitation and emphysema was much higher than expected from the independent effects of both factors (aOR 8.90). Moreover, patients with coexisting moderate-to-severe airflow limitation and emphysema had significantly poorer overall survival than any other group.Patients with moderate-to-severe airflow limitation and emphysema had almost nine times the risk of PPCs and poorer survival than patients with neither of these conditions. Integrated assessment of airflow limitation severity and emphysema is necessary for the optimal selection of candidates for lung resection surgery of early-stage NSCLC.

Quantitative CT analysis of pulmonary ground-glass opacity nodules for distinguishing invasive adenocarcinoma from non-invasive or minimally invasive adenocarcinoma: the added value of using iodine mapping.

OBJECTIVES: To determine whether quantitative analysis of iodine-enhanced images generated from dual-energy CT (DECT) have added value in distinguishing invasive adenocarcinoma from non-invasive or minimally invasive adenocarcinoma (MIA) showing ground-glass nodule (GGN). METHODS: Thirty-four patients with 39 GGNs were enrolled in this prospective study and underwent DECT followed by complete tumour resection. Various quantitative imaging parameters were assessed, including virtual non-contrast (VNC) imaging and iodine-enhanced imaging. RESULTS: Of all 39 GGNs, four were adenocarcinoma in situ (AIS) (10 %), nine were MIA (23 %), and 26 were invasive adenocarcinoma (67 %). When assessing only VNC imaging, multivariate analysis revealed that mass, uniformity, and size-zone variability were independent predictors of invasive adenocarcinoma (odds ratio [OR] = 19.92, P = 0.02; OR = 0.70, P = 0.01; OR = 16.16, P = 0.04, respectively). After assessing iodine-enhanced imaging with VNC imaging, both mass on the VNC imaging and uniformity on the iodine-enhanced imaging were independent predictors of invasive adenocarcinoma (OR = 5.51, P = 0.04 and OR = 0.67, P < 0.01). The power of diagnosing invasive adenocarcinoma was improved after adding the iodine-enhanced imaging parameters versus VNC imaging alone, from 0.888 to 0.959, respectively (P = 0.029). CONCLUSION: Quantitative analysis using iodine-enhanced imaging metrics versus VNC imaging metrics alone generated from DECT have added value in distinguishing invasive adenocarcinoma from AIS or MIA. KEY POINTS: Quantitative analysis using DECT was used to distinguish invasive adenocarcinoma. Tumour mass and uniformity were independent predictors of invasive adenocarcinoma. Diagnostic performance was improved after adding iodine parameters to VNC parameters.

Prognostic impact of nomogram based on whole tumour size, tumour disappearance ratio on CT and SUVmax on PET in lung adenocarcinoma.

OBJECTIVES: Lung adenocarcinoma frequently manifests as subsolid nodules, and the solid portion and ground-glass-opacity (GGO) portion on CT have different prognostic significance. Therefore, current T descriptor, defined as the whole tumour diameter without discrimination between solid and GGO, is insufficient. We aimed to determine the prognostic significance of solid tumour size and attempt to include prognostic factors such as tumour disappearance rate (TDR) on CT and SUVmax on PET/CT. METHODS: Five hundred and ninety-five patients with completely resected lung adenocarcinoma were analyzed. We developed a nomogram using whole tumour size, TDR, and SUVmax. External validation was performed in another 102 patients. RESULTS: In patients with tumours measuring ≤2 cm and >2 to 3 cm, disease free survival (DFS) was significantly associated with solid tumour size (P < 0.001), but not with whole tumour size (P = 0.052). Developed nomogram was significantly superior to the conventional T stage (area under the curve of survival ROC; P = 0.013 by net reclassification improvement) in stratification of patient survival. In the external validation group, significant difference was noted in DFS according to proposed T stage (P = 0.009). CONCLUSIONS: Nomogram-based T descriptors provide better prediction of survival and assessment of individual risks than conventional T descriptors. KEY POINTS: • Current measurement of whole tumour diameter including ground-glass opacity is insufficient • TDR enables differentiation between invasive solid portion and non-invasive GGO portion • SUVmax demonstrates the biological aggressiveness of the tumour • We developed a nomogram using whole tumour size, TDR, and SUVmax • Nomogram-based clinical T descriptors provide better prediction of survival.