A clinicopathological study of resected pulmonary nodules with focal pure ground-glass opacity

Significance of stratifin in early progression of lung adenocarcinoma and its potential therapeutic relevance

Lung cancer is the most common cause of global cancer-related mortality, and the main histological type is adenocarcinoma, accounting for 50% of non-small cell lung cancer. In 2015, the World Health Organization (WHO) histological classification defined the concepts of "adenocarcinoma in situ" (AIS) and "minimally invasive adenocarcinoma" (MIA), which are considered to be adenocarcinomas at a very early stage. Although AIS and MIA have a very favorable outcome, once they progress to early but invasive adenocarcinoma (eIA), they can sometimes have a fatal outcome. We previously compared the expression profiles of eIA and AIS, and identified stratifin (SFN; 14-3-3 sigma) as a protein showing significantly higher expression in eIA than in AIS. Expression of SFN is controlled epigenetically by DNA demethylation, and its overexpression is significantly correlated with poorer outcome. In vitro and in vivo analyses have shown that SFN facilitates early progression of adenocarcinoma by enhancing cell proliferation. This review summarizes genetic and epigenetic abnormalities that can occur in early-stage lung adenocarcinoma and introduces recent findings regarding the biological significance of SFN overexpression during the course of lung adenocarcinoma progression. Therapeutic strategies for targeting SFN are also discussed.

Factors distinguishing invasive from pre-invasive adenocarcinoma presenting as pure ground glass pulmonary nodules

Background

To investigate predictors of pathological invasiveness and prognosis of lung adenocarcinoma in patients with pure ground-glass nodules (pGGNs).

Methods

Clinical and computed tomography (CT) features of invasive adenocarcinomas (IACs) and pre-IACs were retrospectively compared in 641 consecutive patients with pGGNs and confirmed lung adenocarcinomas who had undergone postoperative CT follow-up. Potential predictors of prognosis were investigated in these patients.

Results

Of 659 pGGNs in 641 patients, 258 (39.1%) were adenocarcinomas in situ, 265 (40.2%) were minimally invasive adenocarcinomas, and 136 (20.6%) were IACs. Respective optimal cutoffs for age, serum carcinoembryonic antigen concentration, maximal diameter, mean diameter, and CT density for distinguishing pre-IACs from IACs were 53 years, 2.19 ng/mL, 10.78 mm, 10.09 mm, and − 582.28 Hounsfield units (HU). Univariable analysis indicated that sex, age, maximal diameter, mean diameter, CT density, and spiculation were significant predictors of lung IAC. In multivariable analysis age, maximal diameter, and CT density were significant predictors of lung IAC. During a median follow-up of 41 months no pGGN IACs recurred.

Conclusions

pGGNs may be lung IACs, especially in patients aged > 55 years with lesions that are > 1 cm in diameter and exhibit CT density > − 600 HU. pGGN IACs of < 3 cm in diameter have good post-resection prognoses.

Long-term cancer risk associated with lung nodules observed on low-dose screening CT scans

OBJECTIVE

Non-calcified nodules (NCNs) associated with false positive low-dose CT (LDCT) lung cancer screens have been attributed to various causes. Some, however, may represent lung cancer precursors. An association of NCNs with long-term lung cancer risk would provide indirect evidence of some NCNs being cancer precursors.

METHODS

LDCT arm participants in the National Lung Screening Trial (NLST) received LDCT screens at baseline and years 1-2. The relationship between NCNs found on LDCT screens and subsequent lung cancer diagnosis over different time periods was examined at the person and lobe level. For the latter, a lobe had a cancer outcome only if the cancer was located in the lobe. Separate analyses were performed on baseline and post-baseline LDCT findings; for the latter, those with baseline NCNs were excluded and only new (non-pre-existing) NCNs examined. Raw and adjusted rate-ratios (RRs) were computed for presence of NCNs and subsequent lung cancer risk; adjusted RRs controlled for demographic and smoking factors.

RESULTS

26,309 participants received the baseline LDCT screen. Over median 11.3 years follow-up, 1675 lung cancers were diagnosed. Adjusted RRs for time periods 0-4, 4-8 and 8-12 years following the baseline screen were 5.1 (95 % CI:4.4-5.9), 1.5 (95 % CI:1.3-1.9) and 1.5 (95 % CI:1.2-1.8) at the person-level and 14.7 (95 % CI:12.6-17.2), 2.6 (95 % CI: 2.0-3.4) and 2.2 (95 % CI:1.6-2.9) at the lobe-level. 18,585 participants were included in the post-baseline analysis. Adjusted RRs for periods 0-4, 4-8 and 8-11 years were 5.6 (95 % CI: 4.5-7.0), 1.9 (95 % CI: 1.3-2.7) and 1.6 (95 % CI: 0.9-2.9) at the person-level and 19.6 (95 % CI:14.9-25.3), 2.5 (95 % CI:1.3-4.7) and 3.3 (95 % CI:1.4-7.6) at the lobe-level. Raw RRs were similar.

CONCLUSION

NCNs are associated with excess long-term lung cancer risk, suggesting that some may be lung cancer precursors.

Multi-region exome sequencing reveals genomic evolution from preneoplasia to lung adenocarcinoma

There has been a dramatic increase in the detection of lung nodules, many of which are preneoplasia atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA) or invasive adenocarcinoma (ADC). The molecular landscape and the evolutionary trajectory of lung preneoplasia have not been well defined. Here, we perform multi-region exome sequencing of 116 resected lung nodules including AAH (n = 22), AIS (n = 27), MIA (n = 54) and synchronous ADC (n = 13). Comparing AAH to AIS, MIA and ADC, we observe progressive genomic evolution at the single nucleotide level and demarcated evolution at the chromosomal level supporting the early lung carcinogenesis model from AAH to AIS, MIA and ADC. Subclonal analyses reveal a higher proportion of clonal mutations in AIS/MIA/ADC than AAH suggesting neoplastic transformation of lung preneoplasia is predominantly associated with a selective sweep of unfit subclones. Analysis of multifocal pulmonary nodules from the same patients reveal evidence of convergent evolution.

There has been a drastic increase in detection of lung nodules, many of which are precancers, preinvasive, minimally invasive or sometimes invasive lung cancers. Here, Hu et al. perform multi-region exome sequencing to discern the evolutional trajectory from precancers to invasive lung cancers.

Clinical analysis of percutaneous computed tomography-guided injection of cyanoacrylate for localization of 115 small pulmonary lesions in 113 asymptomatic patients

Objective

This study was performed to assess the clinical feasibility, safety, and effectiveness of a computed tomography (CT)–guided cyanoacrylate injection system and investigate the relationship between clinical features and pathologic characteristics of diminutive pulmonary lesions.

Methods

In total, 115 pulmonary nodules from 113 patients (63 female, 50 male) with a diameter of <20 mm were percutaneously localized with a CT-guided cyanoacrylate injection system and then resected.

Results

Of the pure ground-glass opacities (GGOs), 16.0% were atypical adenomatous hyperplasia (AAH), 18.7% were adenocarcinoma in situ (AIS), 49.3% were lung adenocarcinoma (ADC), and 16.0% were benign inflammatory fibrosis/fibrotic scars. Of the mixed GGOs, 18.2% were AAH, 22.7% were AIS, 22.7% were ADC, and 36.4% were benign lesions. Lesions of >10 mm and those located in relation to vessels were significantly more likely to be malignant. The success rate of both the cyanoacrylate injection system and video-assisted thoracoscopic surgery was 100% with no severe complications.

Conclusions

Preoperative localization of small pulmonary nodules using a cyanoacrylate injection system is a safe, simple, and useful technique.

[Value of CT Features on Differential Diagnosis of Pulmonary Subsolid Nodules and Degree of invasion Prediction in Pulmonary Adenocarcinoma]

背景与目的

亚实性肺结节为肺原发腺癌的常见计算机体层成像（computed tomography, CT）表现，依据其CT影像特征预测病理分型对确定临床治疗策略具有临床价值。本研究根据病理分类，回顾性分析良性、不典型腺瘤样增生（atypical adenomatous hyperplasia, AAH）/原位腺癌（adenocarcinoma in situ, AIS）/微侵袭性腺癌（minimally invasive adenocarcinoma, MIA）、侵袭性腺癌三组亚实性肺结节的CT征象，评估其在良恶性鉴别及恶性侵袭程度判别中的价值。

方法

回顾性分析106例经手术切除亚实性结节的CT征象。依据手术病理分为良性和恶性组，恶性组根据侵袭程度分为无/微侵袭组（AAH/AIS/MIA）、侵袭性腺癌组，测量结节大小、实性成分比例、瘤肺界面、形状、边缘、胸膜牵拉征、空气支气管征、结节内血管异常等CT征象。根据单因素分析（χ²检验、非参数检验Mann-Whitney U检验）结果筛选有统计学差异的变量，纳入Logistic回归多因素分析。

结果

Logistic回归分析显示清晰的瘤肺界面、空气支气管征以及结节内血管异常是恶性结节的重要预测指标，风险比分别为38.1（95%CI: 5.0-287.7; P < 0.01）、7.9（95%CI: 1.3-49.3; P=0.03）、7.2（95%CI: 1.4-37.0; P=0.02）。更大的实性成分所占比例是侵袭性腺癌与AAH/AIS/MIA组鉴别的重要指标，其风险比分别为1.04（95%CI: 1.01-1.06, P=0.01）。

结论

亚实性结节中出现清晰的瘤肺界面、空气支气管征、结节内血管异常提示其恶性概率增加。恶性结节中实性成分所占比例越大预示着侵袭性更高。

Clinicopathological Characteristics and Mutations Driving Development of Early Lung Adenocarcinoma: Tumor Initiation and Progression

Lung cancer is the leading cause of cancer-related deaths worldwide, with lung adenocarcinoma representing the most common lung cancer subtype. Among all lung adenocarcinomas, the most prevalent subset develops via tumorigenesis and progression from atypical adenomatous hyperplasia (AAH) to adenocarcinoma in situ (AIS), to minimally invasive adenocarcinoma (MIA), to overt invasive adenocarcinoma with a lepidic pattern. This stepwise development is supported by the clinicopathological and molecular characteristics of these tumors. In the 2015 World Health Organization classification, AAH and AIS are both defined as preinvasive lesions, whereas MIA is identified as an early invasive adenocarcinoma that is not expected to recur if removed completely. Recent studies have examined the molecular features of lung adenocarcinoma tumorigenesis and progression. EGFR-mutated adenocarcinoma frequently develops via the multistep progression. Oncogene-induced senescence appears to decrease the frequency of the multistep progression in KRAS- or BRAF-mutated adenocarcinoma, whose tumor evolution may be associated with epigenetic alterations and kinase-inactive mutations. This review summarizes the current knowledge of tumorigenesis and tumor progression in early lung adenocarcinoma, with special focus on its clinicopathological characteristics and their associations with driver mutations (EGFR, KRAS, and BRAF) as well as on its molecular pathogenesis and progression.

[Progressions on Diagnosis and Treatment of Ground-glass Opacity]

近年来，肺部磨玻璃影（ground-glass opacity, GGO）逐渐得到了肿瘤科和胸外科医生的普遍关注。GGO是指肺部CT表现为密度轻微增加，增加程度小于实性改变，呈模糊的云雾状，并可见其内血管和支气管纹理。GGO多数情况下呈惰性，但也可进一步发展为肺腺癌，这使其治疗方案的选择颇为棘手；近年来GGO发现率的日益增加也使其关注度得到大大提升。许多报道都从组织学、放射诊断学、治疗学等多个方面对GGO的诊治进行了探讨。本文综述了近10年来学界对GGO的诊断和处理的进展，希望临床医生能更好地认识这个问题，在临床工作中收集并总结更多循证学证据，以指导未来的临床诊治方案的选择。

Biomarkers in phase I-II chemoprevention trials: lessons from the NCI experience

Early phase clinical trials are an essential component of chemopreventive drug development to identify signals of drug efficacy that can subsequently be explored definitively in phase III trials. Whereas phase I trials focus on safety and identification of optimal dose and schedule for cancer prevention, phase II trials focus on intermediate endpoints that are variably related to cancer development. The United States National Cancer Institute supports a programme devoted to early phase cancer prevention clinical trials. The experience, along with the benefits and limitations of the range of biomarker endpoints used in these studies, are reviewed here.

How should we manage small focal pure ground-glass opacity nodules on high-resolution computed tomography? A single institute experience

BACKGROUND

Although the detection of pure ground-glass opacity (p-GGO) nodules on high-resolution chest computed tomography (HRCT) often implies a diagnosis of lung adenocarcinoma, the management of p-GGO nodules remains under discussion.

OBJECTIVE

To assess the correlation between the radiological and pathological diagnoses of small p-GGO on HRCT.

PATIENTS AND METHODS

This is a single-institution retrospective study. We analyzed 89 consecutive patients, including 33 patients with resected p-GGO nodule(s) equal or less than 20 mm in maximal diameter on axial images of HRCT.

RESULTS

Thirty-nine patients underwent locoregional treatment (Treatment group), including surgical resection in 33 and stereotactic body radiation therapy in six. The remaining 50 patients were observed (Observation group) using periodic chest HRCT. The median follow-up time was 30.4 (4.9-102.5) months in the Treatment group and 44.8 (0.4-1125.8) months in the Observation group. During the follow-up period, the p-GGO nodules increased in size in eight patients over a median of 20.6 (12.1-50.6) months, with increased attenuation in three patients over a median of 20.6 (12.1-50.6) months, and either decreased in size or disappeared in four patients over a median of 6.9 (2.0-11.2) months. Thirty-three patients with 47 nodules underwent surgical resection, including 41 adenocarcinomas, one neuroendocrine tumor, three cases of atypical adenomatous hyperplasia and two benign lesions. The frequency of invasive adenocarcinoma was higher among the larger p-GGO nodules.

CONCLUSIONS

Careful observation and decision making with respect to the timing of intervention in cases of p-GGO nodules are warranted.

Surgery for undiagnosed ground glass pulmonary nodules: decision making using serial computed tomography

BACKGROUND

Although long-term observation of ground glass nodules on computed tomography facilitates the ability to distinguish malignant lesions from benign lesions, the resulting treatment delay can increase the rate of cancer recurrence. We reviewed our surgical cases of pathologically undiagnosed lung nodules possessing ground glass to clarify the clinical impact of selecting surgical candidates based on serial computed tomography, not preoperative biopsy results.

METHODS

A consecutive series of 100 patients with clinically suspected lung cancer possessing ground glass among our prospective database of 262 surgical cases of suspected lung cancer were retrospectively reviewed.

RESULTS

Surgical indication was determined based on the interval change in the outer diameter or internal attenuation of the lesions in 53 patients (increasing lesions), while that was determined based on the specific marginal or internal features of the lesions in 47 patients (non-increasing lesions). The length of preoperative follow-up was significantly longer in the patients with increasing lesions than in the patients with non-increasing lesions (27 vs. 3 months, P < 0.001). The final pathological diagnoses consisted of 97 adenocarcinomas and three non-malignant lesions. All increasing lesions were adenocarcinomas. Surgical biopsy contributed in avoiding futile lobectomy in patients with non-malignant lesions, while that caused false-negative result in one patient with an increasing lesion. Postoperative recurrence occurred in two patients.

CONCLUSIONS

In a surgical series, serial computed tomography-diagnosed ground glass lesions are highly suggestive of adenocarcinoma, especially increasing lesions. Despite spending a long-term preoperative follow-up period without a pathological diagnosis, the surgical outcome is satisfactory. Surgical biopsy for increasing lesions is generally futile.

Diagnosis and management of pulmonary nodules

There are an increased number of pulmonary nodules discovered on CT scan images in part due to those performed for lung cancer screening. Risk stratification and patient involvement is critical in determining management ranging from interval imaging to invasive biopsy or surgery. A definitive diagnosis requires tissue biopsy. The choice of a particular biopsy technique depends on the risks/benefits of the procedure, the diagnostic yield and local expertise. This review will focus on the evaluation and management of pulmonary nodules based on the Fleischner Society and American College of Chest Physician guidelines. There have been recent changes to both societies' recommendations for incidental detection of solid and subsolid nodules, risk stratification, imaging, minimally invasive diagnostic techniques and definitive surgical options.

Short- and long-term lung cancer risk associated with noncalcified nodules observed on low-dose CT

Chemoprevention is an important potential tool in reducing lung cancer incidence. Noncalcified nodules (NCN) observed on low-dose computed tomography (LDCT) have been proposed as intermediate endpoints in chemoprevention trials, but whether NCNs represent cancer precursors is unclear. We analyzed data from subjects in the LDCT arm of the National Lung Screening Trial (NLST) to examine short- and long-term lung cancer risks associated with NCNs and to elucidate whether some NCNs may be cancer precursors. NLST subjects received a baseline and two additional LDCT screens and were followed for a median of 6.5 years. We examined lung cancer incidence over three distinct periods from baseline-0-23 months (short-term), 24-59 months (medium-term), and 60-84 months (long-term)-in relation to baseline NCN characteristics. Spatially, lung cancer incidence was analyzed at the person, lung, and lobe levels relative to NCN location. A total of 26,272 subjects received the baseline LDCT screen, with 468, 413, and 190 lung cancers observed in the three periods. The presence of an NCN gave significantly elevated long-term lung cancer risk ratios (RR) of 1.8, 2.4, and 3.5 at the person, lung, and lobe levels; corresponding short-term RRs were 10.3, 16.8, and 38.0. Ground-glass attenuation was positively associated with long-term lung cancer risk but inversely associated with short-term risk; NCN size was positively associated with short-term risk but not significantly associated with long-term risk. That NCNs convey significantly elevated excess long-term of lung cancer lends evidence to the hypothesis that some NCNs may be cancer precursors.

Pure ground-glass opacity neoplastic lung nodules: histopathology, imaging, and management

OBJECTIVE

The purpose of this article is to discuss histologic diagnosis of pure pulmonary ground-glass opacity nodules (GGNs), high-resolution CT (HRCT) findings and pathologic correlation, and management.

CONCLUSION

When pure GGNs are greater than 15 mm in diameter with nodularity or have high pixel attenuation (>-472 HU), the nodules are more likely to be invasive adenocarcinomas. Sublobar resection with a secured safety margin and without nodal dissection is performed for HRCT-suggested pure-GGN invasive adenocarcinomas and has a 100% 5-year survival rate.

Characteristics and management strategies for the incidental pulmonary nodule

SUMMARY: 

Pulmonary nodules are frequent, unanticipated findings on imaging studies obtained for other purposes across all areas of medical practice. As nodule detection raises concern for malignancy, evaluation and follow-up of an incidental nodule is imperative. Clinicians are charged with counseling patients and directing further evaluation amid uncertainty and anxiety. The goals of follow-up and management are to identify malignant lesions at an early stage, while avoiding unnecessary procedures and potential harm to patients with benign nodules. In this review, we aim to outline the clinical and radiographic characteristics that can aid in likelihood stratification, to identify gaps in our current knowledge, and to present a logical approach to nodule management, based on the available evidence.

Outcomes: wedge resection versus lobectomy for non-small cell lung cancer at the Cancer Centre of Southeastern Ontario 1998-2009

BACKGROUND

Sublobar resection for non-small cell lung cancer (NSCLC) remains controversial owing to concern about local recurrence and long-term survival outcomes. We sought to determine the efficacy of wedge resection as an oncological procedure.

METHODS

We analyzed the outcomes of all patients with NSCLC undergoing surgical resection at the Cancer Centre of Southeastern Ontario between 1998 and 2009. The standard of care for patients with adequate cardiopulmonary reserve was lobectomy. Wedge resection was performed for patients with inadequate reserve to tolerate lobectomy. Predictors of recurrence and survival were assessed. Appropriate statistical analyses involved the χ(2) test, an independent samples t test and Kaplan-Meier estimates of survival. Outcomes were stratified for tumour size and American Joint Committee on Cancer seventh edition TNM stage for non-small cell lung cancer.

RESULTS

A total of 423 patients underwent surgical resection during our study period: wedge resection in 71 patients and lobectomy in 352. The mean age of patients was 64 years. Mean follow-up for cancer survivors was 39 months. There was no significant difference between wedge resection and lobectomy for rate of tumour recurrence, mortality or disease-free survival in patients with stage IA tumours less than 2 cm in diameter.

CONCLUSION

Wedge resection with lymph node sampling is an adequate oncological procedure for non-small cell lung cancer in properly selected patients, specifically, those with stage IA tumours less than 2 cm in diameter.

Evaluation of individuals with pulmonary nodules: when is it lung cancer? Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

OBJECTIVES

The objective of this article is to update previous evidence-based recommendations for evaluation and management of individuals with solid pulmonary nodules and to generate new recommendations for those with nonsolid nodules.

METHODS

We updated prior literature reviews, synthesized evidence, and formulated recommendations by using the methods described in the "Methodology for Development of Guidelines for Lung Cancer" in the American College of Chest Physicians Lung Cancer Guidelines, 3rd ed.

RESULTS

We formulated recommendations for evaluating solid pulmonary nodules that measure > 8 mm in diameter, solid nodules that measure ≤ 8 mm in diameter, and subsolid nodules. The recommendations stress the value of assessing the probability of malignancy, the utility of imaging tests, the need to weigh the benefits and harms of different management strategies (nonsurgical biopsy, surgical resection, and surveillance with chest CT imaging), and the importance of eliciting patient preferences.

CONCLUSIONS

Individuals with pulmonary nodules should be evaluated and managed by estimating the probability of malignancy, performing imaging tests to better characterize the lesions, evaluating the risks associated with various management alternatives, and eliciting their preferences for management.

Chemoprevention of lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

BACKGROUND

Lung cancer is the most common cause of cancer death in men and women in the United States. Cigarette smoking is the main risk factor. Former smokers are at a substantially increased risk of developing lung cancer compared with lifetime never smokers. Chemoprevention refers to the use of specific agents to reverse, suppress, or prevent the process of carcinogenesis. This article reviews the major agents that have been studied for chemoprevention.

METHODS

Articles of primary, secondary, and tertiary prevention trials were reviewed and summarized to obtain recommendations.

RESULTS

None of the phase 3 trials with the agents β-carotene, retinol, 13-cis-retinoic acid, α-tocopherol, N-acetylcysteine, acetylsalicylic acid, or selenium has demonstrated beneficial and reproducible results. To facilitate the evaluation of promising agents and to lessen the need for a large sample size, extensive time commitment, and expense, surrogate end point biomarker trials are being conducted to assist in identifying the most promising agents for later-stage chemoprevention trials. With the understanding of important cellular signaling pathways and the expansion of potentially important targets, agents (many of which target inflammation and the arachidonic acid pathway) are being developed and tested which may prevent or reverse lung carcinogenesis.

CONCLUSIONS

By integrating biologic knowledge, additional early-phase trials can be performed in a reasonable time frame. The future of lung cancer chemoprevention should entail the evaluation of single agents or combinations that target various pathways while working toward identification and validation of intermediate end points.

Diagnosis of lung adenocarcinoma in resected specimens: implications of the 2011 International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification

A new lung adenocarcinoma classification has been published by the International Association for the Study of Lung Cancer, the American Thoracic Society, and the European Respiratory Society. This new classification is needed to provide uniform terminology and diagnostic criteria, most especially for bronchioloalveolar carcinoma. It was developed by an international core panel of experts representing all 3 societies with oncologists/pulmonologists, pathologists, radiologists, molecular biologists, and thoracic surgeons.This summary focuses on the aspects of this classification that address resection specimens. The terms bronchioloalveolar carcinoma and mixed subtype adenocarcinoma are no longer used. For resection specimens, new concepts are introduced, such as adenocarcinoma in situ and minimally invasive adenocarcinoma for small solitary adenocarcinomas with either pure lepidic growth (adenocarcinoma in situ) and predominant lepidic growth with invasion of 5 mm or less (minimally invasive adenocarcinoma), to define the condition of patients who will have 100% or near 100% disease-specific survival, respectively, if they undergo complete lesion resection. Adenocarcinoma in situ and minimally invasive adenocarcinoma are usually nonmucinous, but rarely may be mucinous. Invasive adenocarcinomas are now classified by predominant pattern after using comprehensive histologic subtyping with lepidic (formerly most mixed subtype tumors with nonmucinous bronchioloalveolar carcinoma), acinar, papillary, and solid patterns; micropapillary is added as a new histologic subtype. Variants include invasive mucinous adenocarcinoma (formerly mucinous bronchioloalveolar carcinoma), colloid, fetal, and enteric adenocarcinoma.It is possible that this classification may impact the next revision of the TNM staging classification, with adjustment of the size T factor according to only the invasive component pathologically in adenocarcinomas with lepidic areas.

Percutaneous computed tomography-guided coaxial core biopsy for small pulmonary lesions with ground-glass attenuation

INTRODUCTION

The aim of this study was to investigate the diagnostic value of percutaneous computed tomography (CT)-guided coaxial transthoracic needle biopsy (TNB) for small pulmonary lesions (≤ 3 cm) with persistent ground-glass opacity (GGO).

METHODS

From January 2004 to February 2010, consecutive patients with persistent small GGO lesions (≤ 3 cm) who underwent CT-guided TNB were analyzed. The pathologic results of CT-guided TNB were compared with final diagnoses, and the GGO percentage on CT was correlated with the stromal invasion in surgical pathology.

RESULTS

We performed CT-guided TNB on 1612 patients during the study period. Among them, 55 patients had persistent small GGO lesions (size range 0.5-3.0 cm; 1.72 ± 0.73 cm), 47 were diagnosed with lung adenocarcinomas, and 8 with benign nonspecific lesions. Minor procedure-related complications occurred in 26 patients (47.3%) with small pneumothorax and 11 patients (20.0%) with self-limited mild hemoptysis. The final diagnoses of the 43 patients receiving lobectomy were invasive adenocarcinoma (n = 23), pure bronchioloalveolar carcinoma (n = 19), and mucosa-associated lymphoid tissue lymphoma (n = 1). The diagnostic accuracy was 93.0% (40/43) using CT-guided TNB. Pure GGO lesions had a higher incidence of pure bronchioloalveolar carcinoma than GGO-dominant lesions (70.0% versus 21.7%; p = 0.004). Compared with surgical pathology, stromal invasion was underestimated in 43.5% (10/23) of the TNB specimens, especially in pure GGO lesions (83%, 5/6). In logistic regression analysis, the GGO percentage correlated inversely with stromal tumor invasion (p = 0.0028).

CONCLUSIONS

CT-guided coaxial TNB is a safe and useful method for diagnosing small (≤ 3 cm) persistent GGO lesions. Stromal invasion may be underestimated by TNB in GGO lesions.

Small peripheral lung adenocarcinoma: CT and histopathologic characteristics and prognostic implications

Since the introduction of computed tomography (CT), detection of small lung cancer, especially small peripheral adenocarcinoma, is common. Recently, the morphological characteristics, including thin-section CT and pathologic findings, and prognosis of small peripheral lung adenocarcinomas have been studied extensively. The radiologic and microscopic findings correlate well with each other and are closely associated with tumour prognosis. Most importantly, some subtypes of small lung adenocarcinomas with specific CT or pathologic features are curable. Therefore, all defining characteristics (CT, pathologic and prognostic) of this kind of tumour should be integrated to improve our understanding, provide guidelines for management and accurately assess its prognosis.

Multidetector CT features of pulmonary focal ground-glass opacity: differences between benign and malignant

OBJECTIVE

To evaluate different features between benign and malignant pulmonary focal ground-glass opacity (fGGO) on multidetector CT (MDCT).

METHODS

82 pathologically or clinically confirmed fGGOs were retrospectively analysed with regard to demographic data, lesion size and location, attenuation value and MDCT features including shape, margin, interface, internal characteristics and adjacent structure. Differences between benign and malignant fGGOs were analysed using a χ(2) test, Fisher's exact test or Mann-Whitney U-test. Morphological characteristics were analysed by binary logistic regression analysis to estimate the likelihood of malignancy.

RESULTS

There were 21 benign and 61 malignant lesions. No statistical differences were found between benign and malignant fGGOs in terms of demographic data, size, location and attenuation value. The frequency of lobulation (p=0.000), spiculation (p=0.008), spine-like process (p=0.004), well-defined but coarse interface (p=0.000), bronchus cut-off (p=0.003), other air-containing space (p=0.000), pleural indentation (p=0.000) and vascular convergence (p=0.006) was significantly higher in malignant fGGOs than that in benign fGGOs. Binary logistic regression analysis showed that lobulation, interface and pleural indentation were important indicators for malignant diagnosis of fGGO, with the corresponding odds ratios of 8.122, 3.139 and 9.076, respectively. In addition, a well-defined but coarse interface was the most important indicator of malignancy among all interface types. With all three important indicators considered, the diagnostic sensitivity, specificity and accuracy were 93.4%, 66.7% and 86.6%, respectively.

CONCLUSION

An fGGO with lobulation, a well-defined but coarse interface and pleural indentation gives a greater than average likelihood of being malignant.

Approach to the ground-glass nodule

The detection of ground-glass opacity (GGO) is increasingly common. Sufficient data have been accumulated to formulate recommendations for observation, intervention, and treatment modalities. However, an understanding of many nuances and uncertainties in the available data is needed to avoid making management errors. This article discusses the range of possible entities, risk factors and characteristics that help make a presumptive clinical diagnosis, how often and for how long these should be followed when and how a biopsy should be done, how these lesions should be treated, and how multifocal GGOs should be approached.

Ground-glass opacity lesions on computed tomography during postoperative surveillance for primary non-small cell lung cancer

Improvement in chest high-resolution computed tomography (CT) has increased the detection of ground-glass opacity (GGO) lesions. However, there is no clear therapeutic consensus about concurrent GGO lesions detected during postoperative follow-up chest CT after treatment for primary lung cancer. This study retrospectively and prospectively investigated 21 patients in whom 53 GGO lesions were detected during postoperative follow-up CT of non-small cell lung cancer at Kyushu University Hospital from April 2009 to February 2010. We investigated clinicopathological factors, such as age, gender, lesion number, size, laterality, time of identification, and enlargement or emergence of the inner solid component. The malignancy rate of the concurrent GGO lesions was assessed by log-rank test in the Kaplan-Meier curves. Twenty percent of the 53 GGO lesions had malignant radiological findings during the 5-year follow-up after they were first identified by CT. The newly emerging GGO lesions at postoperative CT had significantly more malignant radiological findings (39.5%) than other GGO lesions (9.5%). Three potentially malignant GGO lesions were treated by surgical resection and three were treated by stereotactic radiotherapy. These six treated GGO lesions showed a good clinical course without recurrence after treatment. Special attention should be paid to newly emerging GGO lesions after resection of primary non-small cell lung cancer. It is necessary to select an appropriate treatment, taking account of various factors such as the laterality and number of GGO lesions or the pathological stage of the postoperative lung cancer.

Lung cancer risk prediction to select smokers for screening CT--a model based on the Italian COSMOS trial

Screening with low-dose helical computed tomography (CT) has been shown to significantly reduce lung cancer mortality but the optimal target population and time interval to subsequent screening are yet to be defined. We developed two models to stratify individual smokers according to risk of developing lung cancer. We first used the number of lung cancers detected at baseline screening CT in the 5,203 asymptomatic participants of the COSMOS trial to recalibrate the Bach model, which we propose using to select smokers for screening. Next, we incorporated lung nodule characteristics and presence of emphysema identified at baseline CT into the Bach model and proposed the resulting multivariable model to predict lung cancer risk in screened smokers after baseline CT. Age and smoking exposure were the main determinants of lung cancer risk. The recalibrated Bach model accurately predicted lung cancers detected during the first year of screening. Presence of nonsolid nodules (RR = 10.1, 95% CI = 5.57-18.5), nodule size more than 8 mm (RR = 9.89, 95% CI = 5.84-16.8), and emphysema (RR = 2.36, 95% CI = 1.59-3.49) at baseline CT were all significant predictors of subsequent lung cancers. Incorporation of these variables into the Bach model increased the predictive value of the multivariable model (c-index = 0.759, internal validation). The recalibrated Bach model seems suitable for selecting the higher risk population for recruitment for large-scale CT screening. The Bach model incorporating CT findings at baseline screening could help defining the time interval to subsequent screening in individual participants. Further studies are necessary to validate these models.

Accuracy of CT parameters for assessment of tumour size and aggressiveness in lung adenocarcinoma with bronchoalveolar elements

Accurate determination of tumour size in lung adenocarcinoma with bronchoalveolar features (BAC) is important for the determination of TNM (tumour, nodes, metastasis) scores used in staging, prognosis and therapy response assessment. However, tumour sizes derived using lung window (LW) CT or soft-tissue/mediastinal window (MW) CT often give different results. This study examines which measurement correlates best with actual tumour size and which best identifies advanced disease. This retrospective study included 43 BAC patients who underwent surgical resection with mediastinal lymphadenectomy <4 weeks post CT scan. The largest unidimensional tumour diameter on each CT window was compared with actual histopathological tumour size (HP). LW, MW and HP size measurements and a recently described CT parameter - the modified tumour shadow disappearance rate (mTDR) = (1 - [MW/LW]) - were then used to determine which parameter best discriminated between the presence or absence of advanced disease. There was no difference between HP and LW sizes, but MW significantly underestimated HP size (p<0.0001). Unlike MW (p = 0.01) and mTDR (p = 0.001), neither HP (p = 0.14) nor LW (p = 0.10) distinguished between patients with or without advanced disease. On receiver operating characteristic (ROC) analysis at a cut-off of ≤0.13, the sensitivity and specificity of mTDR for detecting advanced disease were 69% and 89%, respectively. In patients with tumours ≤3 cm, only mTDR remained a significant predictor of advanced disease (p = 0.017), with best cut-off at ≤0.20, giving a sensitivity and specificity of 71% and 94%, respectively. MW better predicts advanced disease than LW and might also need to be recorded for RECIST (response evaluation criteria in solid tumours) assessment for T staging of BAC; however, mTDR appears to be an even better predictor and should also be used.

International association for the study of lung cancer/american thoracic society/european respiratory society international multidisciplinary classification of lung adenocarcinoma

INTRODUCTION

Adenocarcinoma is the most common histologic type of lung cancer. To address advances in oncology, molecular biology, pathology, radiology, and surgery of lung adenocarcinoma, an international multidisciplinary classification was sponsored by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society. This new adenocarcinoma classification is needed to provide uniform terminology and diagnostic criteria, especially for bronchioloalveolar carcinoma (BAC), the overall approach to small nonresection cancer specimens, and for multidisciplinary strategic management of tissue for molecular and immunohistochemical studies.

METHODS

An international core panel of experts representing all three societies was formed with oncologists/pulmonologists, pathologists, radiologists, molecular biologists, and thoracic surgeons. A systematic review was performed under the guidance of the American Thoracic Society Documents Development and Implementation Committee. The search strategy identified 11,368 citations of which 312 articles met specified eligibility criteria and were retrieved for full text review. A series of meetings were held to discuss the development of the new classification, to develop the recommendations, and to write the current document. Recommendations for key questions were graded by strength and quality of the evidence according to the Grades of Recommendation, Assessment, Development, and Evaluation approach.

RESULTS

The classification addresses both resection specimens, and small biopsies and cytology. The terms BAC and mixed subtype adenocarcinoma are no longer used. For resection specimens, new concepts are introduced such as adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) for small solitary adenocarcinomas with either pure lepidic growth (AIS) or predominant lepidic growth with ≤ 5 mm invasion (MIA) to define patients who, if they undergo complete resection, will have 100% or near 100% disease-specific survival, respectively. AIS and MIA are usually nonmucinous but rarely may be mucinous. Invasive adenocarcinomas are classified by predominant pattern after using comprehensive histologic subtyping with lepidic (formerly most mixed subtype tumors with nonmucinous BAC), acinar, papillary, and solid patterns; micropapillary is added as a new histologic subtype. Variants include invasive mucinous adenocarcinoma (formerly mucinous BAC), colloid, fetal, and enteric adenocarcinoma. This classification provides guidance for small biopsies and cytology specimens, as approximately 70% of lung cancers are diagnosed in such samples. Non-small cell lung carcinomas (NSCLCs), in patients with advanced-stage disease, are to be classified into more specific types such as adenocarcinoma or squamous cell carcinoma, whenever possible for several reasons: (1) adenocarcinoma or NSCLC not otherwise specified should be tested for epidermal growth factor receptor (EGFR) mutations as the presence of these mutations is predictive of responsiveness to EGFR tyrosine kinase inhibitors, (2) adenocarcinoma histology is a strong predictor for improved outcome with pemetrexed therapy compared with squamous cell carcinoma, and (3) potential life-threatening hemorrhage may occur in patients with squamous cell carcinoma who receive bevacizumab. If the tumor cannot be classified based on light microscopy alone, special studies such as immunohistochemistry and/or mucin stains should be applied to classify the tumor further. Use of the term NSCLC not otherwise specified should be minimized.

CONCLUSIONS

This new classification strategy is based on a multidisciplinary approach to diagnosis of lung adenocarcinoma that incorporates clinical, molecular, radiologic, and surgical issues, but it is primarily based on histology. This classification is intended to support clinical practice, and research investigation and clinical trials. As EGFR mutation is a validated predictive marker for response and progression-free survival with EGFR tyrosine kinase inhibitors in advanced lung adenocarcinoma, we recommend that patients with advanced adenocarcinomas be tested for EGFR mutation. This has implications for strategic management of tissue, particularly for small biopsies and cytology samples, to maximize high-quality tissue available for molecular studies. Potential impact for tumor, node, and metastasis staging include adjustment of the size T factor according to only the invasive component (1) pathologically in invasive tumors with lepidic areas or (2) radiologically by measuring the solid component of part-solid nodules.

CT fluoroscopy-guided cutting needle biopsy of focal pure ground-glass opacity lung lesions: diagnostic yield in 83 lesions

OBJECTIVE

The objective of our study was to retrospectively determine the diagnostic yield of CT fluoroscopy-guided cutting needle biopsy of focal pure ground-glass opacity lung lesions.

MATERIALS AND METHODS

Biopsies were performed using 20-G coaxial cutting needles for 83 focal pure ground-glass opacity lung lesions (mean lesion size, 12.1mm). After excluding the lesions for which biopsy specimens were unobtainable and final diagnoses were undetermined, the diagnostic yield, including sensitivity and specificity for a diagnosis of malignancy and accuracy, was calculated. The lesions were then divided into 2 groups: the diagnostic failure group, comprising lesions with false-negative results and for which a biopsy specimen was unobtainable; and the diagnostic success group, comprising lesions with true-negative results and true-positive results. Various variables were compared between the 2 groups by univariate analysis.

RESULTS

Biopsy specimens were obtained from 82 lesions, while specimens could not be obtained from 1 lesion. Final diagnosis was undetermined in 16 lesions. The sensitivity and specificity for a diagnosis of malignancy were 95% (58/61) and 100% (5/5), respectively. Diagnostic accuracy was 95% (63/66). The 4 lesions in diagnostic failure group were smaller, deeper, and more likely to be located in the lower lobe and further, for those lesions, number of specimens obtained was smaller, compared with 63 lesions in diagnostic success group. However, none of the differences were statistically significant.

CONCLUSION

CT fluoroscopy-guided cutting needle biopsy provided high diagnostic yield for focal pure ground-glass opacity lung lesions.

Randomized phase II trial of inhaled budesonide versus placebo in high-risk individuals with CT screen-detected lung nodules

Screening CT identifies small peripheral lung nodules, some of which may be pre- or early invasive neoplasia. Secondary end point analysis of a previous chemoprevention trial in individuals with bronchial dysplasia showed reduction in size of peripheral nodules by inhaled budesonide. We performed a randomized, double-blind, placebo-controlled phase IIb trial of inhaled budesonide in current and former smokers with CT-detected lung nodules that were persistent for at least 1 year. A total of 202 individuals received inhaled budesonide, 800 μg twice daily or placebo for 1 year. The primary endpoint was the effect of treatment on target nodule size in a per person analysis after 1 year. The per person analysis showed no significant difference between the budesonide and placebo arms (response rate 2% and 1%, respectively). Although the per lesion analysis revealed a significant effect of budesonide on regression of existing target nodules (P = 0.02), the appearance of new lesions was similar in both groups and thus the significance was lost in the analysis of all lesions. The evaluation by nodule type revealed a nonsignificant trend toward regression of nonsolid and partially solid lesions after budesonide treatment. Budesonide was well tolerated, with no unexpected side effects identified. Treatment with inhaled budesonide for 1 year did not significantly affect peripheral lung nodule size. There was a trend toward regression of nonsolid and partially solid nodules after budesonide treatment. Because a subset of these nodules is more likely to represent precursors of adenocarcinoma, additional follow-up is needed.

Budesonide versus placebo in high-risk population with screen-detected lung nodules: rationale, design and methodology

BACKGROUND

Screening-CT is able to discover small peripheral lung nodules. The nature of these nodules is uncertain but it is reasonable that some of them, in particular the non-solid ones, could represent precancerous lesions. A previous trial showed a reduction in size of peripheral nodules by inhaled budesonide in subjects with bronchial dysplasia.

OBJECTIVE

The primary objective of the study was the evaluation of the effect of budesonide as a chemopreventive agent for lung lesions. The primary endpoint was the modification of lung lesions at ld-CT scan (according to RECIST criteria) after one year of treatment in a person-specific analysis.

METHODS

We performed a randomized, double-blind, placebo controlled trial to evaluate whether inhaled budesonide was able to reduce size and number of persistent, undetermined CT-detected lung nodules in high-risk asymptomatic subjects currently undergoing a five-year CT scan screening program at the European Institute of Oncology.

RESULTS

Trial enrollment started in April 2006 and ended in July 2007 with the randomization of 202 current or former smokers with stable CT-detected lung nodules set to receive budesonide 800 μg or placebo twice daily for 12 months.

CONCLUSION

Our trial represents the first phase II study of a chemopreventive intervention focusing on the peripheral lung, where the majority of lung cancers arise. The research was nested into a screening project with clear advantages in participant accrual and reduction of costs. This paper describes the rationale and design of the study, thus focusing on the methodology and operational aspects of the clinical trial. (Clinicaltrials.gov number. NCT00321893).

A clinicopathological study of resected non-small cell lung cancers 2 cm or less in diameter: a prognostic assessment

The detection and diagnosis of small-sized (2 cm or less) non-small cell lung cancer (NSCLC) has increased with the development of computed tomography (CT). Over 80% of 5-year survival rate has been reported in surgically treated peripheral lung cancer. There are systematic mediastinal and hilar lymph node involvement pleural invasion and intrapulmonary metastasis even with tumor diameter less than 2 cm. The appropriate surgical procedure for such kinds of lung cancer is lobectomy with mediastinal lymph node dissection. To evaluate the prognostic factors and establish the optimal surgical strategy, we analyzed the clinicopathologic features and survival benefit in different tumor size of peripheral small-sized NSCLC. Among the resected lung cancer cases between January 1999 and July 2001, 185 patients were retrospectively analyzed in surgical methods, lymph node involvement, CT scan findings and survival rates. Survival was analyzed by Kaplan-Meier method and log-rank test. Lymph node involvement was recognized in 26(14.05%) patients. There was no statistically significant difference in the incidence of lymph node involvement between tumors 1.6-2.0 cm (17.82%) in diameter than in those 1.0-1.5 cm (11.94%). There was no lymph node metastasis in tumors less than 1.0 cm in diameter. The 5-year survival rates with or without lymph node involvement were 89.98 and 46.15%, respectively, showing significant difference (P=0.000). The overall 5-year survival rate was 83.78%. The 5-year survival rate in tumors 1.6-2.0 cm, 1.0-1.5 cm and less than 1.0 cm in diameter was 80.20, 85.07 and 100%, respectively, and showing significant difference (P=0.035). The 5-year survival rate of 19 patients showing ground-glass opacity (GGO) on CT scan was 94.74% without any metastasis and recurrence after operation. There are systematic mediastinal and hilar lymph node involvement even with tumor diameter less than 2 cm. The results of the present study suggested that systematic lymph node dissection is necessary even for cases with tumor diameter less than 2 cm. However, if the tumor is within 1.0 cm in diameter with obvious GGO showing on chest CT scan, these are good candidates for partial resection without mediastinal lymph node dissection.

The Danish randomized lung cancer CT screening trial--overall design and results of the prevalence round

INTRODUCTION

Lung cancer screening with low dose computed tomography (CT) has not yet been evaluated in randomized clinical trials, although several are underway.

METHODS

In The Danish Lung Cancer Screening Trial, 4104 smokers and previous smokers from 2004 to 2006 were randomized to either screening with annual low dose CT scans for 5 years or no screening. A history of cigarette smoking of at least 20 pack years was required. All participants have annual lung function tests, and questionnaires regarding health status, psychosocial consequences of screening, smoking habits, and smoking cessation. Baseline CT scans were performed in 2052 participants. Pulmonary nodules were classified according to size and morphology: (1) Nodules smaller than 5 mm and calcified (benign) nodules were tabulated, (2) Noncalcified nodules between 5 and 15 mm were rescanned after 3 months. If the nodule increased in size or was larger than 15 mm the participant was referred for diagnostic workup.

RESULTS

At baseline 179 persons showed noncalcified nodules larger than 5 mm, and most were rescanned after 3 months: The rate of false-positive diagnoses was 7.9%, and 17 individuals (0.8%) turned out to have lung cancer. Ten of these had stage I disease. Eleven of 17 lung cancers at baseline were treated surgically, eight of these by video assisted thoracic surgery resection.

CONCLUSIONS

Screening may facilitate minimal invasive treatment and can be performed with a relatively low rate of false-positive screen results compared with previous studies on lung cancer screening.

Malignant pure pulmonary ground-glass opacity nodules: prognostic implications

Objective

This study was designed to evaluate follow-up results in terms of patient prognosis for malignant pulmonary nodules depicted as pure ground-glass opacity (GGO) lesion observed at high-resolution CT (HRCT).

Materials and Methods

Surgical removal for malignant GGO nodules was accomplished in 58 patients (26 men, 32 women; mean age, 57 years; age range, 29-78 years). Patient prognoses were assessed by patient clinical status and the presence of changes in nodule size determined after a follow-up HRCT examination. Differences in patient prognoses were compared for nodule number, size, surgical method, change in size before surgical removal, and histopathological diagnosis by use of Fisher's exact test and Pearson's chi-squared test.

Results

Of the 58 patients, 40 patients (69%) were confirmed to have a bronchioloalveolar carcinoma (BAC) and 18 patients (31%) were confirmed to have an adenocarcinoma with a predominant BAC component. Irrespective of nodule size, number, treatment method, change in size before surgical removal and histopathological diagnosis, neither local recurrence nor a metastasis occurred in any of these patients as determined at a follow-up period of 24 months (range; 12-65 months). Of 14 patients with multiple GGO nodules, all of the nodules were resected without recurrence in six patients. In the remaining eight patients, the remaining nodules showed no change in size in seven cases and a decrease in size in one case as determined after a follow-up CT examination.

Conclusion

Prognoses in patients with pure GGO malignant pulmonary nodules are excellent, and not significantly different in terms of nodule number, size, surgical method, presence of size change before surgical removal and histopathological diagnosis.

Pulmonary nodular ground-glass opacities in patients with extrapulmonary cancers: what is their clinical significance and how can we determine whether they are malignant or benign lesions?

BACKGROUND

The clinical significance of pulmonary nodular ground-glass opacities (NGGOs) in patients with extrapulmonary cancers is not known, although there is an urgent need for study on this topic. The purpose of this study, therefore, was to investigate the clinical significance of pulmonary NGGOs in these patients, and to develop a computerized scheme to distinguish malignant from benign NGGOs.

METHODS

Fifty-nine pathologically proven pulmonary NGGOs in 34 patients with a history of extrapulmonary cancer were studied. We reviewed the CT scan characteristics of NGGOs and the clinical features of these patients. Artificial neural networks (ANNs) were constructed and tested as a classifier distinguishing malignant from benign NGGOs. The performance of ANNs was evaluated with receiver operating characteristic analysis.

RESULTS

Twenty-eight patients (82.4%) were determined to have malignancies. Forty NGGOs (67.8%) were diagnosed as malignancies (adenocarcinomas, 24; bronchioloalveolar carcinomas, 16). Among the rest of the NGGOs, 14 were atypical adenomatous hyperplasias, 4 were focal fibrosis, and 1 was an inflammatory nodule. There were no cases of metastasis appearing as NGGOs. Between malignant and benign NGGOs, there were significant differences in lesion size; the presence of internal solid portion; the size and proportion of the internal solid portion; the lesion margin; and the presence of bubble lucency, air bronchogram, or pleural retraction (p < 0.05). Using these characteristics, ANNs showed excellent accuracy (z value, 0.973) in discriminating malignant from benign NGGOs.

CONCLUSIONS

Pulmonary NGGOs in patients with extrapulmonary cancers tend to have high malignancy rates and are very often primary lung cancers. ANNs might be a useful tool in distinguishing malignant from benign NGGOs.

CT detected indeterminate pulmonary nodules in a chemoprevention trial of fluticasone

INTRODUCTION

In animal models of lung carcinogenesis, inhaled corticosteroids appear to reduce the number of new lung tumors. In a trial of budesonide in smokers with bronchial dysplasia, the proportion of indeterminate CT detected pulmonary nodules that resolved was larger in the treatment group. We performed a secondary analysis of CT data of subjects at risk of lung cancer enrolled in a chemoprevention trial of fluticasone.

METHODS

Subjects with bronchial squamous metaplasia or dysplasia had a baseline chest CT scan. They were randomized to fluticasone or a placebo. After 6 months a repeat CT was performed and the change in number and size of nodules was evaluated.

RESULTS

Two hundred and one subjects were screened. Of the 108 volunteers included in the study, 74 were male, mean age was 53 years and mean number of pack years 48. Baseline: 35 subjects had 91 nodules in total, 62% <4mm. In the fluticasone arm more subjects had a decrease and fewer had an increase in number of nodules, however this trend did not reach statistical significance.

CONCLUSION

In this preliminary study there was a tendency of nodules to resolve, however, studies with CT detected nodules as inclusion criterion are needed.

Persistent Pulmonary Nodular Ground-Glass Opacity at Thin-Section CT: Histopathologic Comparisons

PURPOSE

To retrospectively compare pure pulmonary ground-glass opacity (GGO) nodules observed on thin-section computed tomography (CT) images with histopathologic findings.

MATERIALS AND METHODS

The institutional review board approved this study and waived informed consent. Histopathologic specimens were obtained from 53 GGO nodules in 49 patients. CT scans were assessed in terms of nodule size, shape, contour, internal characteristics, and the presence of a pleural tag. The findings obtained were compared with histopathologic results. Differences in thin-section CT findings according to histopathologic diagnoses were analyzed by using the Kruskal-Wallis test or Fisher exact test.

RESULTS

Of 53 nodules in 49 patients (20 men, 29 women; mean age, 54 years; range, 29-78 years), 40 (75%) proved to be broncholoalveolar cell carcinoma (BAC) (n=36) or adenocarcinoma with predominant BAC component (n=4), three (6%) atypical adenomatous hyperplasia, and 10 (19%) nonspecific fibrosis or organizing pneumonia. No significant differences in morphologic findings on thin-section CT scans were found among the three diseases (all P>0.05). A polygonal shape (25%, 10 of 40 nodules) and a lobulated or spiculated margin (45%, 18 of 40) in BAC or adenocarcinoma with predominant BAC component were caused by interstitial fibrosis or infiltrative tumor growth. A polygonal shape and a lobulated or spiculated margin were observed in two (20%) and three (30%) of 10 nodules, respectively, in organizing pneumonia/fibrosis were caused by granulation tissue aligned in a linear manner in perilobular regions with or without interlobular septal thickening.

CONCLUSION

About 75% of persistent pulmonary GGO nodules are attributed to BAC or adenocarcinoma with predominant BAC component, and at thin-section CT, these nodules do not manifest morphologic features that distinguish them from other GGO nodules with different histopathologic diagnoses.

Adenocarcinoma of the lung: current concepts in radiologic diagnosis and management

PURPOSE OF REVIEW

Since the introduction especially of multidetector computed tomography scanners, detection of peripheral pulmonary nodules as small as 2-3 mm is now a frequent event even in individuals without a significant smoking history. This preponderance of small indeterminate nodules has necessitated reconsideration of the natural history of malignant lung tumors, in particular peripheral adenocarcinomas, as well as current clinical and radiologic guidelines to aid in the management of these lesions.

RECENT FINDINGS

New information within the radiologic, pathologic and surgical literature is currently redefining nodule characterization. Most important has been the growing awareness of the prevalence of 'so-called' sub-solid pulmonary nodules, with important implications for revising our understanding of the natural history of these lesions as it impacts guidelines for nodule management.

SUMMARY

Reassessment of our approach to small pulmonary nodules, while controversial, is now requisite as newer insights into the computed tomography appearance and natural history of small adenocarcinomas of the lung become apparent. Recognition of suspicious morphology and accurate measurements of volume doubling time, in particular, should aid in the management of these lesions.