Early detection of bronchial lesions using newly developed videoendoscopy-based autofluorescence bronchoscopy

Robotic nipple-sparing mastectomy complication rate compared to traditional nipple-sparing mastectomy: a systematic review and meta-analysis

Breast cancer is worldwide the most common cause of cancer in women and causes the second most common cancer-related death. Nipple-sparing mastectomy (NSM) is commonly used in therapeutic and prophylactic settings. Furthermore, (preventive) mastectomies are, besides complications, also associated with psychological and cosmetic consequences. Robotic NSM (RNSM) allows for better visualization of the planes and reducing the invasiveness. The aim of this study was to compare the postoperative complication rate of RNSM to NSM. A systematic search was performed on all (R)NSM articles. The primary outcome was determining the overall postoperative complication rate of traditional NSM and RNSM. Secondary outcomes were comparing the specific postoperative complication rates: implant loss, hematoma, (flap)necrosis, infection, and seroma. Forty-nine studies containing 13,886 cases of (R)NSM were included. No statistically significant differences were found regarding postoperative complications (RNSM 3.9%, NSM 7.0%, p = 0.070), postoperative implant loss (RNSM 4.1%, NSM 3.2%, p = 0.523), hematomas (RNSM 4.3%, NSM 2.0%, p = 0.059), necrosis (RNSM 4.3%, NSM 7.4%, p = 0.230), infection (RNSM 8.3%, NSM 4.0%, p = 0.054) or seromas (RNSM 3.0%, NSM 2.0%, p = 0.421). Overall, there are no statistically significant differences in complication rates between NSM and RNSM.

Detection of breast cancer precursor lesions by autofluorescence ductoscopy

PURPOSE

Autofluorescence is an image enhancement technique used for the detection of cancer precursor lesions in pulmonary and gastrointestinal endoscopy. This study evaluated the feasibility of addition of autofluorescence to ductoscopy for the detection of intraductal breast cancer precursor lesions.

METHODS

An autofluorescence imaging system, producing real-time computed images combining fluorescence intensities, was coupled to a conventional white light ductoscopy system. Prior to surgery, ductoscopy with white light and autofluorescence was evaluated under general anaesthesia in women scheduled for therapeutic or prophylactic mastectomy. Endoscopic findings in both modes were compared, marked and correlated with histology of the surgical specimen.

RESULTS

Four breast cancer patients and five high-risk women, with a median age of 47 years (range 23-62) were included. In autofluorescence mode, two intraductal lesions were seen in two breast cancer patients, which had an increase in the red-to-green fluorescence intensity compared with the surrounding tissue. One lesion had initially been missed by white light ductoscopy but was clearly visible in subsequent autofluorescence mode. One endoscopic finding was classified as suspicious by white light, but was negative in autofluorescence mode and showed normal histology.

CONCLUSIONS

This study demonstrates for the first time the in vivo feasibility of autofluorescence ductoscopy to detect pathologically confirmed breast cancer precursor lesions in both breast cancer patients and high-risk women that were occult under white light.

Photodynamic Diagnosis for Pleural Disseminated Lesions of Lung Cancer Using a Combination of 5-Aminolevulinic Acid and Autofluorescence Observation System

PURPOSE

We developed a diagnostic method for pleural disseminated lesions of lung cancer using a combination of 5-aminolevulinic acid (5ALA) and autofluorescence observation system. We utilized a phenomenon in which externally ingested 5ALA is metabolized to protoporphyrin IX, a precursor of heme, which remains inside malignant cells and emits red fluorescence of approximately 630 nm. The diagnosis was made employing an observation system based on autofluorescence emitted from normal tissues that we have investigated.

METHODS

Between January 2017 and April 2019, we examined 82 lung cancer patients with suspected pleural invasion. We orally administered 5ALA (20 mg/m2) to the patients 4 hours before surgery, and malignant pleural lesions were thoracoscopically visualized using the autofluorescence observation system.

RESULTS

(1) Pleural disseminated lesions were observed in six patients. Of these lesions, two were not detected by usual white light inspection, and the use of this method enabled the diagnosis of disseminated lesions. (2) Regarding the diagnosis of lung cancer pleural invasion to estimate the risk of pleural dissemination, if limited to adenocarcinoma, the sensitivity was 93.9%; specificity, 74.3%; positive predictive value, 60.8%; and negative predictive value, 96.2%.

CONCLUSION

This method may facilitate the detection of minute disseminated lesions that are difficult to detect by usual inspection. In addition, the degree of pleural invasion may be diagnosed to evaluate the need for limited resection such as segmentectomy.

Role of I-scan technique in screening for lung cancer in smokers with positive sputum cytology

Background

Lung cancer has a very poor prognosis and high mortality. Positive sputum for malignant and/or atypical cells warrants the need for fibreoptic bronchoscopy. White light bronchoscopy (WLB) is usually unable to detect preinvasive lesions; therefore, autofluorescence bronchoscopy (AFB) was introduced as a gold standard for detecting such lesions. The aim of this work was to investigate the role of I-scan as a screening tool for cancer in smoker patients showing positive sputum cytology.

Results

New suspicious findings under I-scan occurred in 11 patients (36.7%). The overall sensitivity of WLB alone to diagnose malignancy is 23.3%, in contrast to an added sensitivity of 50% when I-scan was combined with white light (p value < 0.05). The specificity of I-scan could not be assessed in the absence of control cases (true negatives). No major complications or deaths occurred. Haemorrhage and bronchospasm were the commonest minor complications.

Conclusions

The addition of I-scan to the routine white light examination can increase the overall sensitivity of bronchoscopic screening in cases of sputum suspicious for malignancy if put in experienced hand. The suggested increase in procedure duration due to the combined use of I-scan and white light bronchoscopy is not associated with life-threatening complications.

Comparison of autofluorescence and white-light bronchoscopies performed with the Evis Lucera Spectrum for the detection of bronchial cancers: a meta-analysis

Background

Many recent studies have reported that autofluorescence bronchoscopy (AFB) has a superior sensitivity and decreased specificity in the diagnosis of bronchial cancers when compared with white-light bronchoscopy (WLB). We specifically analyzed the diagnostic performances of autofluorescence imaging video bronchoscopy (AFI) performed with the Evis Lucera Spectrum from Olympus, which is a relatively novel approach in detecting and delineating bronchial cancers, and compared it to the older WLB method.

Methods

We searched the PubMed, Embase, Web of Science, and CNKI databases from inception to July 12^th, 2018 for trials in which patients were diagnosed with lung cancer via concurrent or combined use of AFI and WLB. The included studies were required to have a histologic diagnosis as the gold standard comparison, and a sufficient amount of data was extracted to assess the diagnostic capacity. A 2×2 table was constructed, and the area under the receiver-operating characteristic curve (AUC) of AFI and WLB was estimated by using a stochastic model for diagnostic meta-analysis using STATA software.

Results

A total of 10 articles were eligible for the meta analysis, comprising 1,830 patients with complete data included in the analysis. AFI showed a superior sensitivity of 0.92 (95% CI, 0.88-0.95) over WLB's 0.70 (95% CI, 0.58-0.80) with P<0.01, and a comparable specificity of 0.67 (95% CI, 0.51-0.80) compared with WLB's 0.78 (95% CI, 0.68-0.86) with P=0.056. Egger's test P value (0.225) demonstrated that there was no publication bias.

Conclusions

Our research showed that in the evaluation of bronchial cancers, AFI was superior to conventional WLB. With its higher sensitivity, AFI could be valuable for avoiding misdiagnosis.

Devices for image-guided lung interventions: State-of-the-art review

Lung cancer is the leading cause of cancer-related death. According to the American Cancer Society, there were an estimated 222,500 new cases of lung cancer and 155,870 deaths from lung cancer in the United States in 2017. Accurate localization in lung interventions is one of the keys to reducing the death rate from lung cancer. In this study, a total of 217 publications from 2006 to 2017 about designs of medical devices for localization in lung interventions were screened, shortlisted, and categorized by localization principle and reviewed for functionality. Each study was analyzed for engineering characteristics and clinical significance. Research regarding interventional imaging equipment, navigation systems, and surgical devices was reviewed, and both research prototypes and commercial products were discussed. Finally, the future directions and existing challenges were summarized, including real-time intra-procedure guidance, accuracy of localization, clinical application, clinical adoptability, and clinical regulatory issues.

Autofluorescence-based optical biopsy: An effective diagnostic tool in hepatology

Autofluorescence emission of liver tissue depends on the presence of endogenous biomolecules able to fluoresce under suitable light excitation. Overall autofluorescence emission contains much information of diagnostic value because it is the sum of individual autofluorescence contributions from fluorophores involved in metabolism, for example, NAD(P)H, flavins, lipofuscins, retinoids, porphyrins, bilirubin and lipids, or in structural architecture, for example, fibrous proteins, in close relationship with normal, altered or diseased conditions of the liver. Since the 1950s, hepatocytes and liver have been historical models to study NAD(P)H and flavins as in situ, real-time autofluorescence biomarkers of energy metabolism and redox state. Later investigations designed to monitor organ responses to ischaemia/reperfusion were able to predict the risk of dysfunction in surgery and transplantation or support the development of procedures to ameliorate the liver outcome. Subsequently, fluorescent fatty acids, lipofuscin-like lipopigments and collagen were characterized as optical biomarkers of liver steatosis, oxidative stress damage, fibrosis and disease progression. Currently, serum AF is being investigated to improve non-invasive optical diagnosis of liver disease. Validation of endogenous fluorophores and in situ discrimination of cancerous from non-cancerous tissue belong to the few studies on liver in human subjects. These reports along with other optical techniques and the huge work performed on animal models suggest many optically based applications in hepatology. Optical diagnosis is currently offering beneficial outcomes in clinical fields ranging from the respiratory and gastrointestinal tracts, to dermatology and ophthalmology. Accordingly, this review aims to promote an effective bench to bedside transfer in hepatology.

Image enhancement technology in bronchoscopy: a prospective multicentre study in lung cancer

Introduction

Patients with lung cancer may present with additional lesions in the central airways. Earlier studies have shown a relationship between vessel diameter, pattern and grade of malignancy. High-definition (HD+) bronchoscopy with image enhancement techniques (i-scan) detected more vascular abnormalities but correlation with pathology has not yet been established.

Methods

In this investigator-initiated, randomised, controlled, crossover, multicentre study in patients with suspected lung cancer, a HD+ bronchoscopy was performed with i-scan1 and i-scan2 settings in random order. Biopsies, visual grade and vascular pattern classification were obtained by endoscopists and blinded evaluation.

Results

In 107 patients, vascular patterns were classified in 48 tumours. Abrupt-ending vessels were predominantly found in squamous cell carcinoma but overall correlation between vessel pattern and histology was not significant (p=0.339). Additional lesions were detected in 35 patients (33%) with a correlation between vessel pattern and high-grade (pre-)invasive lesions (p<0.001). In 8.4% of the patients, relevant second lesions were detected which determined treatment and staging in 3% of all patients. Interobserver agreement was excellent for visual grading of the airway epithelium, but low for classifying vascular patterns. No significant detection rate difference was found by blinded and unblinded evaluation.

Conclusion

HD+ bronchoscopy with i-scan image enhancement readily detects additional lesions. In one-third of all the patients, additional lesions were detected. Their vascular pattern correlates to pathology outcome, but the interobserver correlation for vascular pattern classification is low. These lesions were relevant in 8.4% and affected treatment and work-up in 3% of the cases.

Trial registration number

NCT02285426; Results.

[Modern approaches to the diagnosis of precancerous pathology and early lung cancer]

AIM

To assess the possibilities of modern diagnostic techniques to diagnose precancerous pathology and early central lung cancer.

MATERIAL AND METHODS

Analysis of Russian and foreign publications for precancerous pathology and early lung cancer, results and comparison of various diagnostic techniques.

RESULTS

Central lung cancer has a stepwise development with transformation of normal bronchial epithelium to hyperplastic followed by focal metaplasia, dysplasia, cancer in situ (CIS) and microinvasive cancer. Fluorography, chest X-ray, computed tomography, magnetic resonance imaging and sputum cytology examination are used to diagnose lung cancer. However, endoscopy plays a leading role in diagnosis of early central lung cancer which rapidly and effectively detects changes of tracheobronchial tree mucosa at the initial stages of carcinogenesis thanks to the use of modern techniques (spectral, autofluorescent and ZOOM - endoscopy).

White light, autofluorescence and narrow-band imaging bronchoscopy for diagnosing airway pre-cancerous and early cancer lesions: a systematic review and meta-analysis

BACKGROUND

We aimed to summarize the diagnostic accuracy of white light bronchoscopy (WLB) and advanced techniques for airway pre-cancerous lesions and early cancer, such as autofluorescence bronchoscopy (AFB), AFB combined with WLB (AFB + WLB) and narrow-band imaging (NBI) bronchoscopy.

METHODS

We searched for eligible studies in seven electronic databases from their date of inception to Mar 20, 2015. In eligible studies, detected lesions should be confirmed by histopathology. We extracted and calculated the 2×2 data based on the pathological criteria of lung tumor, including high-grade lesions from moderate dysplasia (MOD) to invasive carcinoma (INV). Random-effect model was used to pool sensitivity, specificity, diagnostic odds ratio (DOR) and the area under the receiver-operating characteristic curve (AUC).

RESULTS

In 53 eligible studies (39 WLB, 39 AFB, 17 AFB + WLB, 6 NBI), diagnostic performance for high-grade lesions was analyzed based on twelve studies (10 WLB, 7 AFB, 7 AFB + WLB, 1 NBI), involving with totally 2,880 patients and 8,830 biopsy specimens. The sensitivity, specificity, DOR and AUC of WLB were 51% (95% CI, 34-68%), 86% (95% CI, 73-84%), 6 (95% CI, 3-13) and 77% (95% CI, 73-81%). Those of AFB and AFB + WLB were 93% (95% CI, 77-98%) and 86% (95% CI, 75-97%), 52% (95% CI, 37-67%) and 71% (95% CI, 56-87%), 15 (95% CI, 4-57) and 16 (95% CI, 6-41), and 76% (95% CI, 72-79%) and 82% (95% CI, 78-85%), respectively. NBI presented 100% sensitivity and 43% specificity.

CONCLUSIONS

With higher sensitivity, advanced bronchoscopy could be valuable to avoid missed diagnosis. Combining strategy of AFB and WLB may contribute preferable diagnosis rather than their alone use for high-grade lesions. Studies of NBI warrants further investigation for precancerous lesions.

Accuracy of autofluorescence in diagnosing oral squamous cell carcinoma and oral potentially malignant disorders: a comparative study with aero-digestive lesions

Presently, various studies had investigated the accuracy of autofluorescence in diagnosing oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMD) with diverse conclusions. This study aimed to assess its accuracy for OSCC and OPMD and to investigate its applicability in general dental practice. After a comprehensive literature search, a meta-analysis was conducted to calculate the pooled diagnostic indexes of autofluorescence for premalignant lesions (PML) and malignant lesions (ML) of the oral cavity, lung, esophagus, stomach and colorectum and to compute indexes regarding the detection of OSCC aided by algorithms. Besides, a u test was performed. Twenty-four studies detecting OSCC and OPMD in 2761 lesions were included. This demonstrated that the overall accuracy of autofluorescence for OSCC and OPMD was superior to PML and ML of the lung, esophagus and stomach, slightly inferior to the colorectum. Additionally, the sensitivity and specificity for OSCC and OPMD were 0.89 and 0.8, respectively. Furthermore, the specificity could be remarkably improved by additional algorithms. With relatively high accuracy, autofluorescence could be potentially applied as an adjunct for early diagnosis of OSCC and OPMD. Moreover, approaches such as algorithms could enhance its specificity to ensure its efficacy in primary care.

High definition bronchoscopy: a randomized exploratory study of diagnostic value compared to standard white light bronchoscopy and autofluorescence bronchoscopy

Background

Videobronchoscopy is an essential diagnostic procedure for evaluation of the central airways and pivotal for the diagnosis and staging of lung cancer. Technological improvements have resulted in high definition (HD) images with advanced real time image enhancement techniques (i-scan).

Objectives

In this study we aimed to explore the sensitivity of HD+ i-scan bronchoscopy for detection of epithelial changes like vascular abnormalities and suspicious preinvasive lesions, and tumors.

Methods

In patients scheduled for a therapeutic or diagnostic procedure under general anesthesia videos of the bronchial tree were made using 5 videobronchoscopy modes in random order: normal white light videobronchoscopy (WLB), HD-bronchoscopy (HD), HD bronchoscopy with surface enhancement technique (i-scan1), HD with surface- and tone enhancement technique (i-scan2) and dual mode autofluorescence videobronchoscopy (AFB). The videos were scored in random order by two independent and blinded expert bronchoscopists.

Results

In 29 patients all videos were available for analysis. Vascular abnormalities were scored most frequently in HD + i-scan2 bronchoscopy (1.33 ± 0.29 abnormal or suspicious sites per patient) as compared to 0.12 ± 0.05 site for AFB (P = 0.003). Sites suspicious for preinvasive lesions were most frequently reported using AFB (0.74 ± 0.12 sites per patient) as compared to 0.17 ± 0.06 for both WLB and HD bronchoscopy (P = 0.003). Tumors were detected equally by all modalities. The preferred modality was HD bronchoscopy with i-scan (tone- plus surface and surface enhancement in respectively 38% and 35% of cases P = 0.006).

Conclusions

This study shows that high definition bronchoscopy with image enhancement technique may result in better detection of subtle vascular abnormalities in the airways. Since these abnormalities may be related to preneoplastic lesions and tumors this is of clinical relevance. Further investigations using this technique relating imaging to histology are warranted.

[Quantization Methodology of Autofluorescence Bronchoscopy Image in the YUV System]

背景与目的

通过对不同病理类型的自荧光气管镜（autofluorescence bronchoscope, AFB）图像目标区域的YUV定量分析，确定区分不同疾病类型的最佳判别指标，探讨AFB在中央型支气管肺癌诊断中的价值。

方法

对研究对象进行白光气管镜+AFB检查，二者在镜下存在异常者行活检。并对荧光图像显示病变部位通过MATLAB图像测量软件进行YUV定量分析。根据正常支气管粘膜、炎症、低级别上皮样瘤变、高级别上皮样瘤变、浸润性癌的病理结果分组。研究各组与YUV值间的关系，所得数据采用SPSS 11.5软件进行统计学处理。

结果

Y值在浸润性癌和LGD组间存在统计学差异（P=0.040），在浸润性癌和炎症组也存在明显统计学差异（P < 0.001）。其他的各组间无统计学差异。U值在浸润性癌和HGD、LGD、炎症、正常支气管粘膜组之间存在统计学差异（P < 0.050），能较好鉴别正常粘膜及恶性病变。V值在浸润性癌和LGD组（P=0.003）、炎症组（P < 0.001）、正常支气管粘膜组（P < 0.001）存在统计学差异，能有效鉴别浸润性癌及良性疾病。V值在正常支气管粘膜组与HGD组（P=0.001）、炎症组（P=0.004）间比较也具有统计学差异。

结论

利用YUV色彩空间系统针对支气管和肺良恶性疾病鉴别有一定临床应用价值，为临床气管镜诊断肺癌及癌前病变提供有效科学依据。

Photodynamic diagnoses of malignant pleural diseases using the autofluorescence imaging system

BACKGROUND

We conducted a study on photodynamic diagnosis (PDD) using autofluorescence in video-assisted thoracic surgery for minute intrathoracic small dissemination or early malignant pleural mesothelioma.

METHODS

Autofluorescence is the spontaneous emission of light that occurs when mitochondria, lysosomes, and other intracellular organelles absorb light. In normal tissues, green autofluorescence of approximately 520 nm is observed in response to 400-450 nm blue excitation rays. However, in cancer lesions, green autofluorescence is reduced due to thickening of the mucosal epithelium, a decrease in autofluorescent substances, etc., and the color spectrum thus shifts to red-violet. This phenomenon is the basis of PDD.

RESULTS

The color spectrum shift was observed in all tumors located on the pleural surface but not in cases with pleural fibrous disease. Among patients with primary lung cancer, those with pleural infiltration (pl) scores of 1 or greater showed color spectrum shifts due to reduced autofluorescence.

CONCLUSION

Localization of pleural lesions by autofluorescence imaging was found to be useful. In primary lung cancer cases, differentiation between pl0 and pl1 lesions appears to be useful for determining therapeutic strategies including surgical procedures.

Diagnosis and treatment of bronchial intraepithelial neoplasia and early lung cancer of the central airways: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

BACKGROUND

Bronchial intraepithelial lesions may be precursors of central airway lung carcinomas. Identification and early treatment of these preinvasive lesions might prevent progression to invasive carcinoma.

METHODS

We systematically reviewed the literature to develop evidence-based recommendations regarding the diagnosis and treatment of intraepithelial lesions.

RESULTS

The risk and timeline for progression of bronchial intraepithelial lesions to carcinoma in situ (CIS) or invasive carcinoma are not well understood. Multiple studies show that autofluorescence bronchoscopy (AFB) is more sensitive that white light bronchoscopy (WLB) to identify these lesions. In patients with severe dysplasia or CIS in sputum cytology who have chest imaging studies showing no localizing abnormality, we suggest use of WLB; AFB may be used as an adjunct when available. Patients with known severe dysplasia or CIS of central airways should be followed with WLB or AFB, when available. WLB or AFB is also suggested for patients with early lung cancer who will undergo resection for delineation of tumor margins and assessment of synchronous lesions. However, AFB is not recommended prior to endobronchial therapy for CIS or early central lung cancer. Several endobronchial techniques are recommended for the treatment of patients with superficial limited mucosal lung cancer who are not candidates for resection.

CONCLUSION

Additional information is needed about the natural history and rate of progression of preinvasive central airway lesions. Patients with severe dysplasia or CIS may be treated endobronchially; however, it remains unclear if these therapies are associated with improved patient outcomes.

Detection and minimally invasive treatment of early squamous lung cancer

Non-small cell lung cancer (NSCLC) is the most common cause of cancer deaths worldwide. The majority of patents presenting with NSCLC have advanced disease, which precludes curative treatment. Early detection and treatment might result in the identification of more patients with early central lung cancer and improve survival. In addition, the study of early lung cancer improves understanding of lung carcinogenesis and might also reveal new treatment targets for advanced lung cancer. Bronchoscopic investigation of the central airways can reveal both early central lung cancer in situ (stage 0) and other preinvasive lesions such as dysplasia. In the current review we discuss the detection of early squamous lung cancer, the natural history of preinvasive lesions and whether biomarkers can be used to predict progression to cancer. Finally we will review the staging and management of preinvasive lung cancer lesions and the different therapeutic modalities that are available.

Diagnostic value of autofluorescence bronchoscopy in lung cancer

The role of autofluorescence bronchoscopy (AFB) was primarily investigated in regard to the detection of precancerous lesions of bronchial mucosa. Most of the results confirmed higher sensitivity for the detection of precancerous bronchial lesions, when compared to white light bronchoscopy (WLB) alone. However, it is commonly known that the specificity of AFB remains low. Our findings agree in terms of the detection of premalignant bronchial lesions and early lung cancer, but regarding the detection of synchronous lesions or in the evaluation of lung cancer extension, the specificity of AFB is significantly higher. There is still an ongoing debate in the scientific community whether or not autofluorescence should be used as a screening tool for lung cancer. Results of the majority of published series did not support the general use of AFB as a screening tool for lung cancer; however, these results suggest its use in groups of patients with a high risk of lung cancer. Despite this, some authors still do not recommend its use even in high-risk cases. In recent years, the indications for AFB have been widening and this tool may find its place in routine bronchoscopy. With new indications for AFB, such as the evaluation of tumor extension or follow up after surgical resection, bronchoscopists may make use of this tool more often. A sharp learning curve and a clear distinction between healthy and pathologically altered mucosa make this technology acceptable for inexperienced bronchoscopists. We also investigate new hardware and software improvements in AFB. The addition of backscattered light analysis, ultraviolet spectra, fluorescence-reflectance or dual digital systems could improve the diagnostic yield of this technology.

New aspects of photodynamic therapy for central type early stage lung cancer

BACKGROUND

and Objective Photodynamic therapy (PDT) has come to be considered as the first choice of treatment for central type early stage lung cancer (CELC). Recent advances in the ability to diagnose CELC, and in photosensitizers, as well as sophisticated clinical management, may improve the therapeutic outcome and expand the indications of PDT.

MATERIALS AND METHODS

We made the search for papers on PDT for lung cancer to select the most relevant articles. Based on this review and our recent data, we discussed the best available evidence for the diagnosis, the definition of indications, photosensitizers, and clinical management with regard to PDT.

RESULTS

To obtain complete response (CR) by PDT, the selection of the indications is extremely important, including the extent of the tumor on the bronchial surface and the depth of invasion in the bronchial wall. The development of autofluorescence bronchoscopy (AFB) and endobronchial ultrasonography (EBUS) have had a large impact on diagnostic bronchoscopy for CELC. CELCs less than 1 cm in diameter showed a favorable cure rate by PDT, thus this is a good indication for PDT. The relatively newer photosensitizer NPe6, which has a stronger antitumor effect than Photofrin, showed similar treatment outcome even for large tumors >1.0 cm in diameter. Furthermore, comprehensive management including photodynamic diagnosis before and after PDT should be effective to minimize the possibility of local recurrence after PDT.

CONCLUSION

The present guidelines of PDT for CELC were established based on the data obtained from studies in the 1980's. We postulate that comprehensive diagnosis and the new generation of photosensitizers may increase the CR rate and expand the indications of PDT for larger tumors.

Frontiers in bronchoscopic imaging

Bronchoscopy is a minimally invasive method for diagnosis of diseases of the airways and the lung parenchyma. Standard bronchoscopy uses the reflectance/scattering properties of white light from tissue to examine the macroscopic appearance of airways. It does not exploit the full spectrum of the optical properties of bronchial tissues. Advances in optical imaging such as optical coherence tomography (OCT), confocal endomicroscopy, autofluorescence imaging and laser Raman spectroscopy are at the forefront to allow in vivo high-resolution probing of the microscopic structure, biochemical compositions and even molecular alterations in disease states. OCT can visualize cellular and extracellular structures at and below the tissue surface with near histological resolution, as well as to provide three-dimensional imaging of the airways. Cellular and subcellular imaging can be achieved using confocal endomicroscopy or endocytoscopy. Contrast associated with light absorption by haemoglobin can be used to highlight changes in microvascular structures in the subepithelium using narrow-band imaging. Blood vessels in the peribronchial space can be displayed using Doppler OCT. Biochemical compositions can be analysed with laser Raman spectroscopy, autofluorescence or multispectral imaging. Clinically, autofluorescence and narrow-band imaging have been found to be useful for localization of preneoplastic and neoplastic bronchial lesions. OCT can differentiate carcinoma in situ versus microinvasive cancer. Endoscopic optical imaging is a promising technology that can expand the horizon for studying the pathogenesis and progression of airway diseases such as COPD and asthma, as well as to evaluate the effect of novel therapy.

Optical detection of preneoplastic lesions of the central airways

Current routine diagnosis of premalignant lesions of the central airways is hampered due to a limited sensitivity (white light bronchoscopy) and resolution (computer tomography (CT), positron emission tomography (PET)) of currently used techniques. To improve the detection of these subtle mucosal abnormalities, novel optical imaging bronchoscopic techniques have been developed over the past decade. In this review we highlight the technological developments in the field of endoscopic imaging, and describe their advantages and disadvantages in clinical use.

Update on interventional bronchoscopy for the thoracic radiologist

Interventional bronchoscopy, together with other domains of interventional pulmonology, has experienced tremendous technological advances. Diagnostic applications include endobronchial ultrasound, which enables endoscopists to see through airway walls. White light videobronchoscopy, autofluorescence imaging, and narrow band imaging have enhanced the ability to detect early lung cancer at a preinvasive stage. Electromagnetic navigational bronchoscopy, ultrathin bronchoscopy, and virtual bronchoscopy increase the diagnostic yield of biopsy of small peripheral lung lesions. The options that are currently available for the relief of central airway obstruction are also numerous, with both flexible and rigid bronchoscopic applications. Stents, although dichotomized to silicone and metal, come in various sizes and shapes to suit the requirements of the pathology being treated. Ablative techniques are categorized into those with an immediate effect and those with a delayed effect. Laser, electrocautery, and argon plasma coagulation can immediately relieve obstruction and control hemoptysis, whereas cryosurgery, brachytherapy, and photodynamic therapy have established roles in subacute airway obstruction and in the treatment of early lung cancer. Microdebriders have recently been added to the armamentarium of modalities for mechanical debulking of tumor. Distal airway obstruction has also been targeted with bronchial thermoplasty treatment of refractory asthma and with bronchoscopic lung volume reduction for the management of severe emphysema. This array of new technology has fostered collaborative work with a wide range of other medical specialties to deliver safer, more effective, minimally invasive treatment.

Autofluorescence imaging videobronchoscopy in the detection of lung cancer: from research tool to everyday procedure

Autofluorescence imaging videobronchoscopy (AFI) is one of the new systems of autofluorescence bronchoscopy designed for thorough examination of bronchial mucosa. The integration of autofluorescence and videobronchoscopy provides clear images of normal and pathologically altered bronchial mucosa. Major indications for AFI include evaluation of early-stage lung cancer and detection of precancerous lesions. However, in recent years, the indications for AFI are widening, and this tool might find its place in routine daily bronchoscopic practice. With new indications for AFI, such as evaluation of tumor extension or follow-up after surgical resection, this tool might be more often used by bronchoscopists. A sharp learning curve and clear distinction between healthy and pathologically altered mucosa make this technology acceptable for young and inexperienced bronchoscopists. One of the major disadvantages of AFI is low specificity in the detection of premalignant lesions and early-stage lung cancer. This disadvantage could be overcome with the appearance of new and improved technologies in autofluorescence, such as the addition of backscattered light analysis, ultraviolet spectra, fluorescence-reflectance or dual digital systems. Quantitative image analysis is also one of the ways to improve objectivity and minimize observer errors. However, one of the most appropriate solutions would be the addition of AFI to narrow band imaging, and merging the two technologies into one videobronchoscope.

Bronchoscopy in lung cancer: appraisal of current technology and for the future

Bronchoscopy in the new millennium spells an exciting time for the pulmonologist, which likens to Alice peering through the looking glass into a wonderland of miniaturized probes, optics, and technology that are advancing at a maddening pace. Although scientists continue to push the envelope using nanotechnology that may facilitate further miniaturization of probes to allow imaging at the cellular or molecular level, it is opportune to evaluate the strengths and weaknesses of available technologies and bronchoscopic techniques for the diagnosis and staging of lung cancer, in its early detection and palliation. We appraise current technologies and what they hold for the future.

Early diagnosis of lung cancer using a SAFE-3000 autofluorescence bronchoscopy

The aim of the study was to evaluate the double modality working of a new autofluorescence videobronchoscope SAFE-3000 for the detection and localization of precancerous and malignant lesions. From April to May 2009, 168 patients underwent SAFE-3000 bronchoscopy using 'Twin Mode' and 'Multiple Image Xposition (MIX)' technologies. The study considers only 97 patients with morphological alterations (visual score 2 or 3) of mucosa; four bronchial biopsies (two for every modality) have been performed on every patient. Histological diagnosis of the 388 biopsies revealed normal mucosa in 11 patients, four benign lesions, 27 precancerous lesions and 55 malignant lesions. The sensitivity of the 'Twin Mode' and 'MIX' techniques in the characterization of premalignant and malignant lesions was 96% vs. 100%. The specificity was 60% in both of these technologies. SAFE-3000 autofluorescence bronchoscopy allows an early diagnosis of preneoplastic or neoplastic lesions according to the careful analysis of the bronchial mucosa, due to the complementarity of two modalities 'Twin Mode' and 'MIX'. Based on the relationship between the bronchoscopic goal and the histological results the MIX method contributes more of the new endoscopic technique findings.

Emerging roles for multimodal optical imaging in early cancer detection: a global challenge

Medical imaging technologies have become increasingly important in the clinical management of cancer, and now play key roles in cancer screening, diagnosis, staging, and monitoring response to treatment. Standard imaging modalities such as MRI, PET, and CT require significant financial resources and infrastructure, which limits access to these modalities to those patients in high-resource settings. In contrast, optical imaging strategies, with the potential for reduced cost and enhanced portability, are emerging as additional tools to facilitate the early detection and diagnosis of cancer. This article presents a vision for an expanding role for optical imaging in global cancer management, including screening, early detection at the point-of-care, biopsy guidance, and real-time histology. Multi-modal optical imaging - the combination of widefield and high resolution imaging - has the potential to aid in the detection and management of precancer and early cancer for traditionally underserved populations. Several recent widefield and high-resolution optical imaging technologies are described, along with requirements for implementing such devices into lower-resource - settings.

Autofluorescence videoendoscopy system using the SAFE-3000 for assessing superficial gastric neoplasia

BACKGROUND

Autofluorescence (AF) videoendoscopy has an advantage over ordinary videoendoscopy in the diagnosis of gastric neoplasias, and the aim of the present study was to evaluate the effectiveness of using the SAFE-3000 videoendoscopy system to diagnose superficial gastric neoplasias.

METHODS

Ordinary videoendoscopy, AF videoendoscopy, and chromoendoscopy (CE) were used to diagnose the tumor existence and extent in 14 patients with gastric adenoma, 40 patients with intestinal-type early gastric cancer (EGC) (10 protruded, and 30 depressed), and nine patients with diffuse-type EGC. The diagnostic accuracies of the three kinds of images were evaluated by comparison with the results of histopathological assessment of resected specimens.

RESULTS

For gastric adenomas the diagnostic accuracy between the AF images and white light (WL) images did not differ significantly, and for protruded intestinal-type EGCs and diffuse-type EGCs the diagnostic accuracy did not differ significantly between any of the types of images. For depressed intestinal-type EGCs, the diagnostic accuracy of AF images tended to be higher than that of the WL images (P < 0.05) and it was not significantly different from that of the CE images. The detection rate of pink or orange color in AF images was significantly higher for protruded intestinal-type EGCs than gastric adenomas (P = 0.005), depressed intestinal-type EGCs (P < 0.001), and diffuse-type EGCs (P = 0.027).

CONCLUSIONS

Autofluorescence videoendoscopy using the SAFE-3000 system for gastric neoplasias might be useful for diagnosing depressed intestinal-type early gastric cancers. The detection of orange or pink color in AF images may be efficacious in discriminating protruded intestinal-type early gastric cancers from gastric adenomas.

Outcome of photodynamic therapy using NPe6 for bronchogenic carcinomas in central airways >1.0 cm in diameter

PURPOSE

Most centrally located early lung cancers (CLELC) <1.0 cm in diameter do not invade beyond the bronchial cartilage, and photodynamic therapy (PDT) with Photofrin is currently recommended as a treatment option for such lesions. NPe6 is a second-generation photosensitizer, and because it has a longer absorption band (664 nm) than Photofrin (630 nm), we hypothesized that NPe6-PDT would exert a strong antitumor effect against cancer lesions >1.0 cm in diameter, which are assumed to involve extracartilaginous invasion and to be unsuitable for treatment with Photofrin-PDT.

EXPERIMENTAL DESIGN

Between June 2004 and December 2008, 75 patients (91 lesions) with CLELC underwent NPe6-PDT after the extent of their tumors had been assessed by fluorescence bronchoscopy for photodynamic diagnosis and tumor depth had been assessed by optical coherence tomography.

RESULTS

Seventy cancer lesions < or =1.0 cm in diameter and 21 lesions >1.0 cm in diameter were identified, and the complete response rate was 94.0% (66 of 70) and 90.4% (19 of 21), respectively. After the mass of large tumors and deeply invasive tumors had been reduced by electrocautery, NPe6-PDT was capable of destroying the residual cancer lesions.

CONCLUSION

NPe6-PDT has a strong antitumor effect against CLELCs >1.0 cm in diameter that have invaded beyond the bronchial cartilage, thereby enabling the destruction of residual cancer lesions after mass reduction of large nodular- or polypoid-type lung cancers by electrocautery. The PDT guidelines for lung cancers should therefore be revised because use of NPe6-PDT will enable expansion of the clinical indications for PDT.

Influence of narrow band imaging (NBI) videobronchoscopy on the assessment of central lung cancer extension and therapeutic decision

OBJECTIVES

Determination of specificity and sensitivity of narrow band imaging (NBI) in the assessment of tumor extension in centrally located lung cancer, when compared to white light bronchoscopy (WLB) alone, and evaluation of possible influence of NBI on therapeutic decision in patients with lung cancer.

PATIENTS AND METHODS

We evaluated 36 patients with suspected lung cancer. All patients underwent WLB followed by NBI bronchoscopy. We were using videobronchoscope BF-1T180 and EVIS LUCERA SPECTRUM processor unit.

RESULTS

Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for NBI in the assessment of tumor extension were 97.8, 85, 93.7, and 94.4%, respectively; and for WLB 92.3, 60, 69.6, and 88.9%, respectively. In 14 patients, NBI revealed more extensive tumor than WLB (p =.0057). In eight patients, NBI showed significant influence on therapeutic decision (p =.001).

CONCLUSION

NBI videobronchoscopy had better specificity and sensitivity in the assessment of tumor extension in centrally located lung cancer, and it might play a significant role in the therapeutic decision.

[Early diagnosis of lung cancer: impact of autofluorescence bronchoscopy]

INTRODUCTION

Less than 15% of all patients survive five years after a diagnosis of lung cancer. This poor prognosis is attributed to a lack of early detection. Among the methods of early diagnosis of bronchial cancer, autofluorescence bronchoscopy allows for the early identification of preinvasive bronchial lesions. The goal of this prospective study is to evaluate the contribution of the autofluorescence bronchoscopy, on a hospital site, over a period of one year.

METHODS

All patients with an indication of autofluorescence bronchoscopy were included in the study. The following parameters were collected: age, sex, smoking status, FEV1, FVC, biopsy sites, histology, duration of examination.

RESULTS

Two hundred and seventy-four patients were included. The average age was 63.8 years (+/-12), the smoking status was 35 packs/year (+/-19). A fluorescence abnormality was detected in 131 patients and 165 sites were biopsied. An histological abnormality was found in 76% of the samples, with 34 hyperplasia (28%), 56 squamous metaplasia (46%), three mild dysplasia (3%), two moderate dysplasia (2%), one severe dysplasia (1%), two carcinomas in situ (2%) and 21 invasive carcinomas (18%).

CONCLUSION

Autofluorescence bronchoscopy is an effective examination for the detection of the preinvasive neoplasic lesions and may be proposed when lung cancer is suspected.

Color fluorescence ratio for detection of bronchial dysplasia and carcinoma in situ

BACKGROUND

Autofluorescence bronchoscopy is more sensitive than conventional bronchoscopy for detecting early airway mucosal lesions. Decreased specificity can lead to excessive biopsy and increased procedural time. Onco-LIFE, a device that combines fluorescence and reflectance imaging, allows numeric representation by expressing red-to-green ratio (R/G ratio) within the region of interest. The aim of the study was to determine if color fluorescence ratio (R/G ratio) added to autofluorescence bronchoscopy could provide an objective means to guide biopsy.

METHODS

Subjects at risk for lung cancer were recruited at two centers: VU University Medical Centre (Amsterdam) and BC Cancer Agency (Canada). R/G ratio for each site appearing normal or abnormal was measured before biopsy. R/G ratios were correlated with pathology, and a receiver operating characteristic curve of R/G ratio for high-grade and moderate dysplasia was done. Following analysis of the training data set obtained from two centers, a prospective validation study was done.

RESULTS

Three thousand three hundred sixty-two adequate biopsies from 738 subjects with their corresponding R/G ratios were analyzed. R/G ratio 0.54 conferred 85% sensitivity and 80% specificity for the detection of high-grade and moderate dysplasia, area under the curve was 0.90, and 95% confidence interval was 0.88 to 0.92. In another 70 different sites that were assessed, kappa measurements of agreement of R/G ratios with visual scores and pathology were 0.66 (P < 0.0001) and 0.61 (P < 0.0001), respectively. R/G ratio combined with visual score improved specificity to 88% (95% confidence interval, 0.73-0.96) for high-grade and moderate dysplasia.

CONCLUSION

Color fluorescence ratio can objectively guide the bronchoscopist in selecting sites for biopsy with good pathologic correlation.

Breast cancer resistant protein (BCRP) is a molecular determinant of the outcome of photodynamic therapy (PDT) for centrally located early lung cancer

The ATP-binding cassette (ABC) transporter protein, BCRP (breast cancer resistance protein)/ABCG2 pumps out some types of photosensitizers used in photodynamic therapy (PDT) and causes resistance to the antitumor effect of PDT. The purpose of this study was to investigate the association between the expression of BCRP and the efficacy of PDT using Photofrin, or the second-generation photosensitizer, NPe6, for centrally located early lung cancers. Using human epidermoid carcinoma cells, A431 cells and the BCRP-overexpressing A431/BCRP cells, we examined the effects of BCRP expression on the effect of PDT by cell viability assay in vitro, and investigated the expression of BCRP by immunohistochemical analysis in 81 tumor samples obtained from patients with centrally located early lung cancers. The A431/BCRP cells were more resistant to Photofrin-PDT than A431 cells in vitro, and Fumitremorgin C, a specific inhibitor of BCRP, reversed the resistance. However, there was no significant difference in the antitumor effect of NPe6-PDT between these cells. All of the 81 centrally located early lung cancer lesions were BCRP-positive (2+, 45 lesions; 1+, 30 lesions) and all the patients were male and heavy smokers (>30 pack-years). The expression of BCRP significantly affected the efficacy of Photofrin-PDT in cancer lesions > or =10mm in diameter (P=0.04). On the other hand, NPe6-PDT exhibited a strong antitumor effect, regardless of the expression status of BCRP. Photofrin may be a substrate of BCRP and be pumped out from the cells, therefore, BCRP may be a molecular determinant of the outcome of Photofrin-PDT.

Autofluorescence videobronchoscopy (AFI) for the assessment of tumor extension in lung cancer

The major objective of our study was to determine the specificity and sensitivity of AFI videobronchoscopy vs. white light videobronchoscopy, in the assessment of lung cancer extent. Secondary objective was to investigate whether or not AFI can reveal greater extension of the tumor, and can it influence therapy making decision. Autofluorescence videobronchoscopy systems are new technology for visualization of bronchial mucosa, and the proper indications for such systems will be determined in the near future. In this prospective trial we have enrolled 27 patients with suspected lung cancer in whom we performed 108 diagnostic biopsies and 54 control biopsies. All patients underwent WL videobronchoscopy followed by Auto Fluorescence Imaging (AFI) examination of tracheobronchial tree. We were using videobronchoscope BF-F260 and EVIS LUCERA SPECTRUM processor unit. Overall specificity for AFI in the diagnostics of lung cancer was found to be 85%, sensitivity was 90%, positive predictive value (PPV) 78%, and negative predictive value (NPV) 94%. Specificity, sensitivity, PPV, and NPV for WL videobronchoscopy in lung cancer diagnostics were 54%, 64%, 51%, and 69%, respectively. Relative sensitivity ratio of AFI over WL videobronchoscopy, which is calculated to be 1.41, confirmed superiority of AFI in lung cancer diagnostics. We confirmed significant correlation between the greater extension of the tumor (assessed with AFI) and the therapeutical decision in lung cancer treatment (p = 0.01). Influence of AFI on therapeutical decision was significant (p = 0.034). AFI videobronchoscopy system yields significantly higher sensitivity and specificity for the assessment of lung cancer extent than WLB videobronchoscopy alone. It had shown to be able to influence therapeutic option for lung cancer treatment. Further studies are needed to evaluate and validate these results.

Detection and localization of intraepithelial neoplasia and invasive carcinoma using fluorescence-reflectance bronchoscopy: an international, multicenter clinical trial

OBJECTIVES

The primary objective of this study was to evaluate the benefit of using a new fluorescence-reflectance imaging system, Onco-LIFE, for the detection and localization of intraepitheal neoplasia and early invasive squamous cell carcinoma. A secondary objective was to evaluate the potential use of quantitative image analysis with this device for objective classification of abnormal sites.

DESIGN

This study was a prospective, multicenter, comparative, single arm trial. Subjects for this study were aged 45 to 75 years and either current or past smokers of more than 20 pack-years with airflow obstruction, forced expiratory volume in 1 second/forced vital capacity less than 75%, suspected to have lung cancer based on either sputum atypia, abnormal chest roentgenogram/chest computed tomography, or patients with previous curatively treated lung or head and neck cancer within 2 years.

MATERIALS AND METHODS

The primary endpoint of the study was to determine the relative sensitivity of white light bronchoscopy (WLB) plus autofluorescence-reflectance bronchoscopy compared with WLB alone. Bronchoscopy with Onco-LIFE was carried out in two stages. The first stage was performed under white light and mucosal lesions were visually classified. Mucosal lesions were classified using the same scheme in the second stage when viewed with Onco-LIFE in the fluorescence-reflectance mode. All regions classified as suspicious for moderate dysplasia or worse were biopsied, plus at least one nonsuspicious region for control. Specimens were evaluated by the site pathologist and then sent to a reference pathologist, each blinded to the endoscopic findings. Positive lesions were defined as those with moderate/severe dysplasia, carcinoma in situ (CIS), or invasive carcinoma. A positive patient was defined as having at least one lesion of moderate/severe dysplasia, CIS, or invasive carcinoma. Onco-LIFE was also used to quantify the fluorescence-reflectance response (based on the proportion of reflected red light to green fluorescence) for each suspected lesion before biopsy.

RESULTS

There were 115 men and 55 women with median age of 62 years. Seven hundred seventy-six biopsy specimens were included. Seventy-six were classified as positive (moderate dysplasia or worse) by pathology. The relative sensitivity on a per-lesion basis of WLB + FLB versus WLB was 1.50 (95% confidence interval [CI], 1.26-1.89). The relative sensitivity on a per-patient basis was 1.33 (95% CI, 1.13-1.70). The relative sensitivity to detect intraepithelial neoplasia (moderate/severe dysplasia or CIS) was 4.29 (95% CI, 2.00-16.00) and 3.50 (95% CI, 1.63-12.00) on a per-lesion and per-patient basis, respectively. For a quantified fluorescence reflectance response value of more than or equal to 0.40, a sensitivity and specificity of 51% and 80%, respectively, could be achieved for detection of moderate/severe dsyplasia, CIS, and microinvasive cancer.

CONCLUSIONS

Using autofluorescence-reflectance bronchoscopy as an adjunct to WLB with the Onco-LIFE system improves the detection and localization of intraepitheal neoplasia and invasive carcinoma compared with WLB alone. The use of quantitative image analysis to minimize interobserver variation in grading of abnormal sites should be explored further in future prospective clinical trial.

In vivo time-resolved spectroscopy of the human bronchial early cancer autofluorescence

Time-resolved measurements of tissue autofluorescence (AF) excited at 405 nm were carried out with an optical-fiber-based spectrometer in the bronchi of 11 patients. The objectives consisted of assessing the lifetime as a new tumor/normal (T/N) tissue contrast parameter and trying to explain the origin of the contrasts observed when using AF-based cancer detection imaging systems. No significant change in the AF lifetimes was found. AF bronchoscopy performed in parallel with an imaging device revealed both intensity and spectral contrasts. Our results suggest that the spectral contrast might be due to an enhanced blood concentration just below the epithelial layers of the lesion. The intensity contrast probably results from the thickening of the epithelium in the lesions. The absence of T/N lifetime contrast indicates that the quenching is not at the origin of the fluorescence intensity and spectral contrasts. These lifetimes (6.9 ns, 2.0 ns, and 0.2 ns) were consistent for all the examined sites. The fact that these lifetimes are the same for different emission domains ranging between 430 and 680 nm indicates that there is probably only one dominant fluorophore involved. The measured lifetimes suggest that this fluorophore is elastin.