Histopathological evaluation of fluorescence bronchoscopy using resected lungs in cases of lung cancer

Health state dependent multiphoton induced autofluorescence in human 3D in vitro lung cancer model

Lung diseases pose the highest risk of death and lung cancer is a top killer among cancers with a mortality rate up to 70% within 1 year after diagnosis. Such a fast escalation of this cancer development makes early diagnosis and treatment a highly challenging task, and currently there are no effective tools to diagnose the disease at an early stage. The ability to discriminate between healthy and tumorous tissue has made autofluorescence bronchoscopy a promising tool for detection of lung cancer; however, specificity of this method remains insufficiently low. Here, we perform autofluorescence imaging of human lung cancer invading a human functional airway using an in vitro model of Non Small Cell Lung Cancer which combines a reconstituted human airway epithelium, human lung fibroblasts and lung adenocarcinoma cell lines, OncoCilAir™. By using two-photon laser induced autofluorescence microscopy combined with spectrally resolved imaging, we found that OncoCilAir™ provides tissue's health dependent autofluorescence similar as observed in lung tissue in patients. Moreover, we found spectral and intensity heterogeneity of autofluorescence at the edges of tumors. This metabolic related heterogeneity demonstrates ability of tumor to influence its microenvironment. Together, our result shows that OncoCilAir™ is a promising model for lung cancer research.

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.

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.

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.

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.

Strategies for high-resolution imaging of epithelial ovarian cancer by laparoscopic nonlinear microscopy

Ovarian cancer remains the most frequently lethal of the gynecologic cancers owing to the late detection of this disease. Here, by using human specimens and three mouse models of ovarian cancer, we tested the feasibility of nonlinear imaging approaches, the multiphoton microscopy (MPM) and second harmonic generation (SHG) to serve as complementary tools for ovarian cancer diagnosis. We demonstrate that MPM/SHG of intrinsic tissue emissions allows visualization of unfixed, unsectioned, and unstained tissues at a resolution comparable to that of routinely processed histologic sections. In addition to permitting discrimination between normal and neoplastic tissues according to pathological criteria, the method facilitates morphometric assessment of specimens and detection of very early cellular changes in the ovarian surface epithelium. A red shift in cellular intrinsic fluorescence and collagen structural alterations have been identified as additional cancer-associated changes that are indiscernible by conventional pathologic techniques. Importantly, the feasibility of in vivo laparoscopic MPM/SHG is demonstrated by using a "stick" objective lens. Intravital detection of neoplastic lesions has been further facilitated by low-magnification identification of an indicator for cathepsin activity followed by MPM laparoscopic imaging. Taken together, these results demonstrate that MPM may be translatable to clinical settings as an endoscopic approach suitable for high-resolution optical biopsies as well as a pathology tool for rapid initial assessment of ovarian cancer samples.

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.

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.

Bronchial Intraepithelial Neoplasia/Early Central Airways Lung Cancer

BACKGROUND

An evidence-based approach is necessary for the localization and management of intraepithelial and microinvasive non-small cell lung cancer in the central airways.

METHODS

Material appropriate to this topic was obtained by literature search of a computerized database. Recommendations were developed by the writing committee and then reviewed by the entire guidelines panel. The final recommendations were made by the Chair and were voted on by the entire committee.

RESULTS

White light bronchoscopy has diagnostic limitations in the detection of microinvasive lesions. Autofluorescence bronchoscopy (AFB) is a technique that has been shown to be a sensitive method for detecting these lesions. In patients with moderate dysplasia or worse on sputum cytology and normal chest radiographic findings, bronchoscopy should be performed. If moderate/severe dysplasia or carcinoma in situ (CIS) is detected in the central airways, then bronchoscopic surveillance is recommended. The use of AFB is preferred if available. In a patient being considered for curative endobronchial therapy to treat microinvasive lesions, AFB is useful. A number of endobronchial techniques as therapeutic options are available for the management of CIS and can be recommended to patients with inoperable disease. In patients with operable disease, surgery remains the mainstay of treatment, although patients may be counseled about these techniques.

CONCLUSIONS

AFB is a useful tool for the localization of microinvasive neoplasia. A number of endobronchial techniques available for the curative treatment can be considered first-line therapy in inoperable cases. For operable cases, the techniques may be considered and discussed with the patients.

Comprehensive diagnostic bronchoscopy of central type early stage lung cancer

Due to advances in interventional bronchoscopy, curative treatment has become possible for central type lung cancer if it is detected in the early stage. However, expertise is required to diagnose the extent of tumor invasion and the depth of tumor involvement by conventional white light bronchoscopy alone, but judgement is still subjective. The development of autofluorescence bronchoscopy (AFB) and endobronchial ultrasonography (EBUS) has had a large impact on diagnostic bronchoscopy in the past decade and have been employed especially for the diagnosis of central type tumors. Objective evaluation by a comprehensive approach using AFB, EBUS and optical coherence tomography (OCT) enables selection of the optimal therapeutic strategy for central type early lung cancer (CELC).

Correlation coefficient mapping in fluorescence spectroscopy: tissue classification for cancer detection

Correlation coefficient mapping has been applied to intrinsic fluorescence spectra of colonic tissue for the purpose of cancer diagnosis. Fluorescence emission spectra were collected of 57 colonic tissue sites in a range of 4 physiological conditions: normal (29), hyperplastic (2), adenomatous (5), and cancerous tissues (21). The sample-sample correlation was used to examine the ability of correlation coefficient mapping to determine tissue disease state. The correlation coefficient map indicates two main categories of samples. These categories were found to relate to disease states of the tissue. Sensitivity, selectivity, predictive value positive, and predictive value negative for differentiation between normal tissue and all other categories were all above 92%. This was found to be similar to, or higher than, tissue classification using existing methods of data reduction. Wavelength-wavelength correlation among the samples highlights areas of importance for tissue classification. The two-dimensional correlation map reveals absorption by NADH and hemoglobin in the samples as negative correlation, an effect not obvious from the one-dimensional fluorescence spectra alone. The integrity of tissue was examined in a time series of spectra of a single tissue sample taken after tissue resection. The wavelength-wavelength correlation coefficient map shows the areas of significance for each fluorophore and their relation to each other. NADH displays negative correlation to collagen and FAD, from the absorption of emission or fluorescence resonance energy transfer. The wavelength-wavelength correlation map for the decay set also clearly shows that there are only three fluorophores of importance in the samples, by the well-defined pattern of the map. The sample-sample correlation coefficient map reveals the changes over time and their impact on tissue classification. Correlation coefficient mapping proves to be an effective method for sample classification and cancer detection.

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

The combination of white light and autofluorescence bronchoscopy has been reported to show better sensitivity in detecting dysplasia and cancer of the bronchus than white light alone. However, fiberoptic bronchoscopy has been replaced by videoendoscopy at most leading facilities for over a decade. To avoid interruption of the videoendoscopy examination to perform fiberscopy-based autofluorescence examination as well as enhancing the sensitivity of intraepithelial lesions, autofluorescence diagnosis system integrated into a videoendoscope (SAFE 3000, Pentax, Tokyo) was created. A total of 154 consecutive patients were studied using this system, containing 83 known or suspected lung cancer cases, 46 of the cases with abnormal sputum cytology findings, 10 follow up cases following lung cancer operations, and 15 heavy smokers with respiratory symptoms. Abnormal findings were recognized by white light and/or SAFE 3000 at 166 sites and biopsies were taken to evaluate the relationship between endoscopic findings and pathology results. The sensitivity of the system for CIS+dysplasia was 65% in white light and 90% in SAFE. This videoendoscopy-based autofluorescence system had significantly higher sensitivity for intraepithelial lesions than white light videoendoscopy alone.

Locally recurrent central-type early stage lung cancer < 1.0 cm in diameter after complete remission by photodynamic therapy

BACKGROUND

It is well known that central-type early stage lung cancer < 1.0 cm in diameter shows almost 100% complete response (CR) to photodynamic therapy (PDT). However, we have encountered cases of local recurrence after CR of tumors with a surface diameter < 1.0 cm.

PATIENTS AND METHODS

Ninety-three patients with 114 lesions were followed up, and cases of recurrence after CR has been obtained with initial tumors that had a diameter < 1.0 cm were examined. We compared the cytologic findings of local recurrence after CR to the cytologic findings before PDT. The relationship between the cell features and the depth of bronchial tumor invasion before PDT and on recurrence was evaluated.

RESULTS

The CR and 5-year survival rates of patients with lesions < 1.0 cm were 92.8% (77 of 83 patients) and 57.9%, respectively; meanwhile, in the group of patients with lesions > or = 1.0 cm, CR and 5-year survival rates were 58.1% (18 of 31 patients) and 59.3%. There was a significant difference in efficacy between the two groups (p < 0.001). Recurrences after CR were recognized in 9 of 77 lesions (11.7%) < 1.0 cm. When the recurrent tumor cells showed type I-II (low-to-moderate atypia) at the same site initially treated, CR could be obtained by a second PDT. Type III cells (high-grade atypia) showed the characteristics of tumor cells from deeper layers of the bronchial wall. Local recurrence at the same site may be caused by residual tumor cells from deep layers because of inadequate laser irradiation and penetration.

CONCLUSIONS

To reduce the recurrence rate, it is essential to accurately grasp the tumor extent and the depth of the bronchogenic carcinoma before performing PDT. Analysis of cell features of recurrent lesions after CR appears to be a useful source of information as to the depth of cancer invasion in the bronchial wall.

The natural history of carcinoma in situ involving bronchial resection margins

STUDY OBJECTIVES

Microscopic residual disease in the bronchial resection margins after surgical resection of lung cancer is rare, and its clinical significance remains unsettled. We studied the natural history of patients with carcinoma in situ (CIS) at their bronchial resection margins to focus on the issue of stump recurrence.

METHODS

Eleven individuals who had undergone radical surgery for N0M0 lung tumors were found to have CIS at the bronchial resection margins. All of the resection specimens were reviewed with respect to the pattern of CIS extension and reclassified as follows: superficial CIS, involving surface epithelium only (CIS-S), CIS extending into the submucosal gland ducts but not deeper (CIS-D), and CIS extending into submucosal gland acini (CIS-A). Patients were followed using autofluorescence bronchoscopy and high-resolution computer tomography. Clinical parameters and the local extent of CIS at histology review were correlated with outcome.

RESULTS

Median follow-up was 35 months (range, 15 to 89). Histology review showed two CIS-S cases, six CIS-D cases, and three CIS-A cases. All of the patients with CIS-A developed stump recurrences in contrast with those with only CIS-S. Three patients with CIS-D have developed metachronous primaries in the contralateral lung, whereas the stump region remained free of tumor.

CONCLUSIONS

The presence of CIS in the bronchial resection margin after resection of lung cancers is associated with stump recurrences. Although absolute numbers are too small for firm conclusions, our data suggest that those with deep glandular extension of CIS bear the highest risk of early recurrence. However, the development of new primaries away from the stump region and the possible development of distant disease are equally relevant considerations with respect to the choice of additional therapy.

Detection and Staging of Preinvasive Lesions and Occult Lung Cancer in the Central Airways with 18F-Fluorodeoxyglucose Positron Emission Tomography: A Pilot Study

PURPOSE

To evaluate the role of (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in radiologically occult preinvasive lesions and lung cancer in the central airways.

EXPERIMENTAL DESIGN

Twenty-two patients with 24 preinvasive lesions and early squamous cell cancer (SCC) being occult on high-resolution computed tomography were studied. All lesions were diagnosed based on histology sampled using autofluorescence bronchoscopy. FDG-PET findings were correlated with WHO histologic classification. FDG-PET was considered true-positive when the final diagnosis was SCC and true-negative when the lesions were classified as severe dysplasia or less.

RESULTS

FDG-PET was true-positive in 8 of 11 and true-negative in 11 of 13 cases corresponding with a sensitivity of 73% [95% confidence interval (CI), 0.43-0.91] and specificity of 85% (95% CI, 0.57-0.97). Positive and negative predictive values were 80% (95% CI, 0.48-0.96) and 79% (95% CI, 0.52-0.93), respectively.

CONCLUSIONS

Our very preliminary data suggest that FDG-PET might be useful for the evaluation of early central airway lesions, being positive in most SCC and negative in cases of severe dysplasia. Validation in a larger multicenter study is needed.

What is early lung cancer? A review of the literature

The dismal cure rate of patients with lung cancer and the stage shift hypothesis have propelled the interest to perform screening at large, despite that previous randomized clinical trials failed to show any mortality benefit and the controversial issue of overdiagnosis. Due to early detection programs, a larger number of individuals at risk will be found to harbor small and potentially malignant early stage lesions. The application of non- and minimal invasive techniques for early detection, staging and treatment will become increasingly important. This review deals with the available clinical, surgical and pathological data focusing on early lung cancer lesions < or =1 cm. Literature data from both centrally located and parenchymal lesions < or =3 cm. have been analyzed. For all sub-centimeter lesions, minimal invasive staging and treatment approaches must still be considered inappropriate. Less invasive and less extensive treatment methods may be considered in high risk individuals with < or =1 cm. peripheral lesion showing > or =50 ground glass opacity on high resolution CT scan and those with superficial lesion in their central airways without deeper tumor invasion in the bronchial wall. Caution is necessary, however, as clinical staging remains inferior to pathological staging which is based on tissue samples collected after complete tumor removal and mediastinal lymph nodes dissection have been performed.