Roentgenographically occult lung cancer

Sublobectomy for stage IA1-2 invasive lung adenocarcinoma with consolidation tumor ratio ≤ 0.25

BACKGROUND

Sublobectomy for early-stage non-small cell lung cancer (NSCLC) remains a matter of debate. This study aimed to discuss the feasibility of sublobectomy in patients with pathological-stage IA1-2 confirmed as pathologically invasive but radiologically noninvasive adenocarcinoma.

METHODS

From 2011 to 2019, we screened clinical stage IA1-IA2 lung cancer patients who underwent surgery at the Guangdong Provincial People's Hospital (GDPH). Inclusion criteria were maximum tumor diameter of 2.0 cm or less, consolidation tumor ratio (CTR) ≤ 0.25, and pathologically confirmed invasive adenocarcinoma. Sublobectomy (segmentectomy and wedge resection) and lobectomy groups were created, and propensity scores were computed. The primary endpoints were lung cancer-specific overall survival (LCSS) and LCS- relapse-free survival (LCS-RFS) after adjusting propensity scores.

RESULTS

A total of 1731 patients were screened, and 100 patients were enrolled. The lobectomy group had 51 patients and the limited resection group had 49. No cases relapsed, and two patients died from nontumor causes. For the entire cohort, the 5-year LCSS and 5-year LCS-RFS were 100% in the lobectomy and limited resection groups. When propensity scores matched, there were no differences in LCSS and LCS-RFS between the two groups (LCSS:100%, LCS-RFS 100% in lobectomy and limited resection, respectively).

DISCUSSION

Sublobectomy may be curative for pathologically invasive but radiologically noninvasive adenocarcinoma at pathological stage IA1-2.

Diseasomics: Actionable machine interpretable disease knowledge at the point-of-care

Physicians establish diagnosis by assessing a patient's signs, symptoms, age, sex, laboratory test findings and the disease history. All this must be done in limited time and against the backdrop of an increasing overall workload. In the era of evidence-based medicine it is utmost important for a clinician to be abreast of the latest guidelines and treatment protocols which are changing rapidly. In resource limited settings, the updated knowledge often does not reach the point-of-care. This paper presents an artificial intelligence (AI)-based approach for integrating comprehensive disease knowledge, to support physicians and healthcare workers in arriving at accurate diagnoses at the point-of-care. We integrated different disease-related knowledge bodies to construct a comprehensive, machine interpretable diseasomics knowledge-graph that includes the Disease Ontology, disease symptoms, SNOMED CT, DisGeNET, and PharmGKB data. The resulting disease-symptom network comprises knowledge from the Symptom Ontology, electronic health records (EHR), human symptom disease network, Disease Ontology, Wikipedia, PubMed, textbooks, and symptomology knowledge sources with 84.56% accuracy. We also integrated spatial and temporal comorbidity knowledge obtained from EHR for two population data sets from Spain and Sweden respectively. The knowledge graph is stored in a graph database as a digital twin of the disease knowledge. We use node2vec (node embedding) as digital triplet for link prediction in disease-symptom networks to identify missing associations. This diseasomics knowledge graph is expected to democratize the medical knowledge and empower non-specialist health workers to make evidence based informed decisions and help achieve the goal of universal health coverage (UHC). The machine interpretable knowledge graphs presented in this paper are associations between various entities and do not imply causation. Our differential diagnostic tool focusses on signs and symptoms and does not include a complete assessment of patient's lifestyle and health history which would typically be necessary to rule out conditions and to arrive at a final diagnosis. The predicted diseases are ordered according to the specific disease burden in South Asia. The knowledge graphs and the tools presented here can be used as a guide.

Occult Non-Small Cell Lung Cancer: An Underappreciated Disease

Background: The number of researches on occult non-small cell lung cancer (NSCLC) is modest. Herein, we defined the clinicopathological features, prognosis and survival outcome of this underappreciated tumor, with purpose of obtaining a clearer picture on this disease. Methods: The entire cohort was categorized into two groups (occult NSCLC and other NSCLC) and further into five groups (occult, T1, T2, T3 and T4). A least absolute shrinkage and selection operator (LASSO) penalized Cox regression model was performed to identify the prognostic indicators. A nomogram and a risk-classifying system were formulated. Kaplan–Meier with Log-rank method was carried out to compare overall survival (OS) and cancer specific survival (CSS) differences between groups. Results: 59,046 eligible NSCLC cases (occult NSCLC: 1158 cases; other NSCLC: 57,888 cases) were included. Occult NSCLC accounted for 2.0% of the included cases. Multivariate analysis revealed that age, sex, tumor location, histology, grade and surgery were prognostic factors for OS. The corresponding prognostic nomogram classified occult NSCLC patients into low-risk and high-risk group, and its performance was acceptable. Survival curves demonstrated that occult NSCLC patients exhibited worse survivals than other NSCLC. In further analyses, the survival of low-risk occult NSCLC and stage T3 NSCLC were comparable, and the high-risk occult NSCLC patients still owned the worst survival rate. Conclusions: Occult NSCLC was an aggressive tumor with poor prognosis, and surgery was the preferred treatment. More attention should be paid to this overlooked disease due to no evidence of tumor imaging.

Incidence and survival analyses for occult lung cancer between 2004 and 2015: a population-based study

Background

This study aimed to investigate the incidence and long-term survival outcomes of occult lung cancer between 2004 and 2015.

Methods

A total of 2958 patients were diagnosed with occult lung cancer in the 305,054 patients with lung cancer. The entire cohort was used to calculate the crude incidence rate. Eligible 52,472 patients (T1-xN0M0, including 2353 occult lung cancers) were selected from the entire cohort to perform survival analyses after translating T classification according to the 8th TNM staging system. Cancer-specific survival curves for different T classifications were presented.

Results

The crude incidence rate of occult lung cancer was 1.00 per 100 patients, and it was reduced between 2004 and 2015 [1.4 per 100 persons in 2004; 0.6 per 100 persons in 2015; adjusted risk ratio = 0.437, 95% confidence interval (CI) 0.363–0.527]. In the survival analysis, there were 2206 death events in the 2353 occult lung cancers. The results of the multivariable analysis revealed that the prognoses with occult lung cancer were similar to patients with stage T3N0M0 (adjusted hazard ratio = 1.054, 95% CI 0.986–1.127, p = 0.121). Adjusted survival curves presented the same results. In addition, adjusted for other confounders, female, age ≤ 72 years, surgical treatment, radiotherapy, adenocarcinoma, and non-squamous and non-adenocarcinoma non-small cell carcinoma were independent protective prognostic factors (all p < 0.05).

Conclusions

Occult lung cancer was uncommon. However, the cancer-specific survival of occult lung cancer was poor, therefore, we should put the assessment of its prognoses on the agenda. Timely surgical treatment and radiotherapy could improve survival outcomes for those patients. Besides, we still need more research to confirm those findings.

The promises and challenges of early non-small cell lung cancer detection: patient perceptions, low-dose CT screening, bronchoscopy and biomarkers

Lung cancer survival statistics are sobering with survival ranking among the poorest of all cancers despite the addition of targeted therapies and immunotherapies. However, improvements in tools for early detection hold promise. The Nederlands–Leuvens Longkanker Screenings Onderzoek (NELSON) trial recently corroborated the findings from the previous National Lung Screening Trial low‐dose Computerised Tomography (NLST) screening trial in reducing lung cancer mortality. Biomarker research and development is increasing at pace as the molecular life histories of lung cancers become further unravelled. Low‐dose CT screening (LDCT) is effective but targets only those at the highest risk and is burdensome on healthcare. An optimally designed CT screening programme at best will only detect a low proportion of overall lung cancers as only those at very high‐risk meet screening criteria. Biomarkers that help risk stratify suitable patients for LDCT screening, and those that assist in determining which LDCT detected nodules are likely to represent malignant disease are needed. Some biomarkers have been proposed as standalone lung cancer diagnosis tools. Bronchoscopy technology is improving, with better capacity to identify and obtain samples from early lung cancers. Clinicians need to be aware of each early lung cancer detection method’s inherent limitations. We anticipate that the future of early lung cancer diagnosis will involve a synergistic, multimodal approach, combining several early detection methods.

A prospective 5-year follow-up study after limited resection for lung cancer with ground-glass opacity

OBJECTIVES

The incidence of small-sized pulmonary adenocarcinomas with ground-glass opacity (GGO) has recently increased, with excellent postoperative prognosis. The limited resection of such cancers has been deemed to be acceptable based on retrospective studies. We conducted a prospective multi-institutional study evaluating the validity of limited resection for small-sized pulmonary adenocarcinoma with GGO.

METHODS

The inclusion criteria were 25-80 years of age, no prior treatment, a maximum tumour diameter of 8-20 mm, a GGO ratio of ≥ 80%, clinical T1N0M0, lower 18F-fluorodeoxyglucose accumulation than the mediastinum, resectable by sublobar resection, pulmonary lobectomy tolerable and an intraoperative pathological diagnosis of bronchiloalveolar carcinoma. Wedge resection was preferred, but segmentectomy was permitted. Disease-specific survival and overall survival were analysed.

RESULTS

From November 2006 to April 2012, 73 patients were enrolled from 13 institutions. One patient was ineligible, and the remaining 72 patients were preregistered. The tumours of 3 and 14 patients were intraoperatively diagnosed as benign lesions and adenocarcinomas with mixed subtype, respectively. Intraoperative cytological/histological examination of surgical margin was not performed in 2 patients, and the remaining 53 patients were ultimately eligible for this study. The mean tumour size was 14.0 mm and the mean GGO ratio was 95.9%. Thirty-nine and 14 patients underwent wedge resection and segmentectomy, respectively. Although all tumours were intraoperatively diagnosed as bronchioloalveolar carcinomas, 6 were ultimately diagnosed as adenocarcinoma with a mixed subtype. No completion lobectomy was performed. As of 1 May 2017, no recurrence of the original lung cancer was observed during 60.0-126.3 months after surgery. Two patients died from other diseases. The 5-year disease-specific and overall survival rates were 100% and 98.1%, respectively. The reduction in the pulmonary function after limited resection was minimal.

CONCLUSIONS

With these criteria, limited resection was performed safely without any recurrence, and the postoperative pulmonary function was well preserved. The outcomes of limited resection for small-sized lung cancer with GGOs that met the criteria of this study were satisfactory.

Successful treatment of limited-stage small-cell lung cancer in the right mainstem bronchus by a combination of chemotherapy and argon plasma coagulation

The current standard-of-care treatment for patients with limited-stage small-cell lung cancer (SCLC) is concurrent chemoradiotherapy for local and systemic control. However, standard-of-care treatment strategies have not been established for those with limited-stage SCLC who have a history of thoracic radiotherapy due to concerns with complications associated with radiation overdose. A 37-year-old male developed an aspergilloma in the postoperative left thoracic space after he was treated with concurrent chemoradiotherapy for mediastinal type lung adenocarcionoma and subsequent left upper lobectomy for heterochronous dual adenocarcinoma. Fiberoptic bronchoscopy was performed to examine the status of the suspected bronchopleural fistula when a polypoid mass was observed in the right mainstem bronchus. A histological examination showed that the mass was SCLC at a clinical stage of cTisN0M0, stageIA, without local invasion. Since thoracic radiotherapy was not an option due to a previous history of thoracic irradiation, a combination treatment of carboplatin and etoposide was administered for 4 cycles and resulted in good partial response. In addition, argon plasma coagulation (APC) was performed as an alternative to curative radiotherapy on day 22 of the 4th cycle. The 5th cycle was administered 7 days after APC at which the anticancer therapy was completed. The patient remains disease-free 60 months after the completion of treatment, which suggests that this combination therapy may resolve very early-stage SCLC.

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.

Early central airways lung cancer

Early central airways lung cancer accounts for very small percentage of all lung cancers. Given this fact, it is much difficult to carry out a prospective randomized comparative clinical trial. Even retrospective studies can offer important information. Early central airways lung cancer is usually detected by sputum cytology. If sputum cytology shows atypical epithelial cells implying malignancy, the next thing we have to do is bronchoscopy. Both autofluorescence bronchoscopy and white light bronchoscopy were superior to white light bronchoscopy alone in detecting this type of lung cancer. Natural history of this cancer showed about the two-thirds of the patients die from original disease within 10 years. If the tumor length is 10 mm or less, photodynamic therapy is a first-line modality. After photodynamic therapy, a 5-year overall survival of about 80 % and a 10-year overall survival of 70 % can be expected. If a cancer does not meet the criteria for photodynamic therapy, surgical resection is recommended, and 5-year overall survival of about 80 % can be expected. Segmentectomy should be considered because of pulmonary function preservation if a tumor is located at segmental bronchi or beyond it. The frequency of multicentricity is high. Treatment strategy for subsequent primary lung cancer is an important key for the prognosis of patients with treated early central airways lung cancer. Surgical resection is still the most reliable treatment of subsequent primary lung cancer, except for in situ or microinvasive carcinoma located centrally, which could be cured by photodynamic therapy.

Perifissural nodules seen at CT screening for lung cancer

PURPOSE

To describe and characterize the potential for malignancy of noncalcified lung nodules adjacent to fissures that are often found in current or former heavy smokers who undergo computed tomography (CT) for lung cancer screening.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained. Baseline and follow-up thin-section multidetector CT scans obtained in 146 consecutive subjects at high risk for lung cancer (age range, 50-75 years; > 30 pack-year smoking history) were retrospectively reviewed. Noncalcified nodules (NCNs) were categorized according to location (parenchymal, perifissural), shape, septal connection, manually measured diameter, diameter change, and lung cancer outcome at 7(1/2) years.

RESULTS

Retrospective review of images from 146 baseline and 311 follow-up CT examinations revealed 837 NCNs in 128 subjects. Of those 837 nodules, 234 (28%), in 98 subjects, were adjacent to a fissure and thus classified as perifissural nodules (PFNs). Multiple (range, 2-14) PFNs were seen in 47 subjects. Most PFNs were triangular (102/234, 44%) or oval (98/234, 42%), were located inferior to the carina (196/234, 84%), and had a septal connection (171/234, 73%). The mean maximal length was 3.2 mm (range, 1-13 mm). During 2-year follow-up in 71 subjects, seven of 159 PFNs increased in size on one scan but were then stable. The authors searched a lung cancer registry 7(1/2) years after study entry and found 10 lung cancers in 139 of 146 study subjects who underwent complete follow-up; none of these cancers had originated from a PFN.

CONCLUSION

PFNs are frequently seen on screening CT scans obtained in high-risk subjects. Although PFNs may show increased size at follow-up CT, the authors in this study found none that had developed into lung cancer; this suggests that the malignancy potential of PFNs is low. (c) RSNA, 2010.

Preinvasive lesions of the bronchus

Preinvasive lesions are considered the precursors of squamous cell carcinoma of the bronchus. Treatment at the preinvasive stage, before the potential for metastasis, may improve survival from squamous cell carcinoma. An understanding of the natural history and outcome of preinvasive lesions is essential for the accurate interpretation studies of their treatment, and decisions regarding the management of individual lesions. The natural history of preinvasive lesions has only been reported in a small number of highly selected patients and uses different inclusion criteria, treatment criteria. and time-periods of follow-up, making it difficult to draw definitive conclusions. High-grade preinvasive lesions carry a risk of progression to carcinoma but most patients have multiple lesions and a significant probability of developing new lesions over time. Distinguishing lesions with malignant potential, the targets for therapy, from those that will regress or remain indolent is difficult. The American College of Chest Physicians guidelines recommend bronchoscopic follow-up of severe dysplasia and carcinoma-in situ. This review of the evidence regarding the natural history and outcome of preinvasive lesions supports this view, but also shows that further studies in individuals at risk for lung cancer are necessary before guidelines for the management of preinvasive lesions can be developed.

Connective tissue-activating peptide III: a novel blood biomarker for early lung cancer detection

PURPOSE

There are no reliable blood biomarkers to detect early lung cancer. We used a novel strategy that allows discovery of differentially present proteins against a complex and variable background.

METHODS

Mass spectrometry analyses of paired pulmonary venous-radial arterial blood from 16 lung cancer patients were applied to identify plasma proteins potentially derived from the tumor microenvironment. Two differentially expressed proteins were confirmed in 64 paired venous-arterial blood samples using an immunoassay. Twenty-eight pre- and postsurgical resection peripheral blood samples and two independent, blinded sets of plasma from 149 participants in a lung cancer screening study (49 lung cancers and 100 controls) and 266 participants from the National Heart Lung and Blood Institute Lung Health Study (45 lung cancer and 221 matched controls) determined the accuracy of the two protein markers to detect subclinical lung cancer.

RESULTS

Connective tissue-activating peptide III (CTAP III)/ neutrophil activating protein-2 (NAP-2) and haptoglobin were identified to be significantly higher in venous than in arterial blood. CTAP III/NAP-2 levels decreased after tumor resection (P = .01). In two independent population cohorts, CTAP III/NAP-2 was significantly associated with lung cancer and improved the accuracy of a lung cancer risk prediction model that included age, smoking, lung function (FEV(1)), and an interaction term between FEV(1) and CTAP III/NAP-2 (area under the curve, 0.84; 95% CI, 0.77 to 0.91) compared to CAPIII/NAP-2 alone.

CONCLUSION

We identified CTAP III/NAP-2 as a novel biomarker to detect preclinical lung cancer. The study underscores the importance of applying blood biomarkers as part of a multimodal lung cancer risk prediction model instead of as stand-alone tests.

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.

Long-term observation of 64 patients with roentgenographically occult lung cancer treated with external irradiation and intraluminal irradiation using low-dose-rate iridium

OBJECTIVE

Therapeutic results of intraluminal irradiation were analyzed in 64 patients with roentgenographically occult lung cancer (ROLC).

METHODS

The subjects were 64 patients who underwent intraluminal irradiation between 1987 and 2003. Radiotherapy was performed by combining external irradiation with intraluminal irradiation using low-dose-rate iridium (four 370-MBq wires) through a catheter with a spacer. The doses of radiation were 0-70 Gy (median value 46 Gy) by external irradiation and 10-60 Gy (median value 29.3 Gy) by intraluminal irradiation.

RESULTS

The therapeutic effect was CR in 63 patients and PR in 1 patient, and local recurrence was observed in a PR case and in seven of the 63 patients who showed CR. The 5-year overall and relapse-free survival rates were 56 (95% CI, 43-69%) and 55% (95% CI, 43-68%), respectively. Fatal pulmonary hemorrhage was observed in one case.

CONCLUSIONS

Considering the facts that ROLC often occurs as multiple cancers and that many patients with ROLC have reduced lung function, radiation therapy by a combination of intraluminal and external irradiation may replace surgery as the first choice for the treatment of this disease.

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.

Detection of pre-invasive endobronchial tumors with D-light/autofluorescence system

Autofluorescence bronchoscopy (AFB) is one of the newly developed diagnostic tools to detect the pre-cancerous lesions in the bronchial tissue. The utility of DLight/AFB in the detection of pre-cancerous lesions was compared to the standard white light bronchoscopy (WLB). In 113 patients (male 106, female 7), who visited hospital for evaluation of lung cancer, WLB and AFB were done and 364 biopsy specimens were obtained from November 2001 to August 2002. The bronchoscopic findings on WLB and AFB were compared to the pathological findings. The pathologic diagnoses of the specimens were as follows: normal in 96; hyperplasia in 69; metaplasia in 32; mild dysplasia in 13, moderate dysplasia in 6, severe dysplasia in 4; carcinoma in situ in 6; invasive carcinoma in 57. The relative sensitivity of adjunctive AFB to WLB vs. WLB alone was 1.5 in moderate dysplasia or worse lesions, and 3.2 in intraepithelial neoplasia. The specificity of adjunctive AFB and WLB alone were 0.91 and 0.5, respectively. The adjunctive AFB to the standard WLB increased the detection rate of the localized pre-invasive lesions. However, there was high rate of false positive in AFB.

Synthesis of 5-aminolevulinic acid (ALA) and itst-butyl ester for the fluorescence detection of early cancer

5-Aminolevulinic acid and its derivatives, which are known to affect the early diagnosis and treatment of cancer, have been synthesized. Simple methods for the synthesis of 5-aminolevulinic acid (ALA), a precursor of porphyrins, have been developed in our laboratory for use in studies on the biosynthesis of porphyrins.

High prevalence of occult endobronchial malignancy in high risk patients with moderate sputum atypia

Early stage radiographically occult lung cancer has a high cure rate, but comprises a small fraction of all lung cancer. Abnormal sputum cytology is one indication for bronchoscopy in patients with chest imaging that is not suspicious for lung cancer. While there is good evidence that sputum cytologic findings of carcinoma, carcinoma in situ or severe atypia predict high rates of diagnosis of lung cancer, less is known of the frequency in which lung cancer is diagnosed in bronchoscopies carried out for the indication of moderate sputum atypia. One small series, published in abstract form only, reported an 8% rate of diagnosis of lung cancer in subjects bronchoscoped for moderate atypia. We tested the hypothesis that moderate sputum atypia is an indicator of occult central airway cancer in a retrospective analysis of a group of high risk subjects, defined as current or former smokers with >30 pack-years tobacco smoking and airflow obstruction with moderate atypia sputum cytology. Seventy-nine such subjects with no evidence of malignancy on chest radiograph at the time bronchoscopy was scheduled underwent white light and autofluorescence bronchoscopy. Lung cancer was found in five subjects; three had invasive squamous cell carcinomas and two had carcinoma in situ. Seven additional subjects had severe dysplasia found on endobronchial biopsy. Moderate sputum atypia may be an important marker of risk for occult endobronchial malignancy in high risk subjects.

Using molecular markers in sputum for the early detection of lung cancer: a review

Recent exciting advances have been made in identifying potential molecular markers in sputum which may soon be ready for validation trials to indicate high risk for lung cancer, especially central airway squamous cell lung cancer. Hopefully, a set of biomarkers will be identified with higher sensitivity, specificity, and enough lead-time compared to traditional cytopathology to justify endobronchial evaluation and local therapy to help reduce lung-cancer mortality in high-risk patients.

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.

Lung cancer screening: a different paradigm

Thoracic computed tomography (CT) is a sensitive method for detecting early lung cancer but has a high false-positive rate and is not sensitive for detecting central preinvasive and microinvasive cancer. Our hypothesis was that automated quantitative image cytometry (AQC) of sputum cells as the first screening method may improve detection rate by identifying individuals at highest risk for lung cancer. A total of 561 volunteer current or former smokers 50 years of age or older, with a smoking history of more than or equal to 30 pack/years, were studied. Among these, 423 were found to have sputum atypia defined as five cells or more with abnormal DNA content using AQC. Noncalcified pulmonary nodules were found in 46% (259/561). Of the 14 detected cancers, 13 were detected in subjects with sputum atypia-nine by CT and four carcinoma in situ/microinvasive cancers by autofluorescence bronchoscopy. One cancer was detected by CT alone. AQC of sputum cells improved the detection rate of lung cancer from 1.8 to 3.1%. CT scan alone would have missed 29% of the cancers. This screening paradigm shift has the additional potential of reducing the number of initial CT scans by at least 25% with further savings in follow-up investigations and treatment.

[Endobronchial brachytherapy: technique and indications]

The endobronchial brachytherapy procedure involves the insertion of an afterloading catheter into bronchus in close proximity to an endoluminal lesion, and to perform limited irradiation sparing as much as possible normal health tissues. The catheter is inserted during a classical flexible bronchoscopy. Three types of indications have been discussed: (i) palliative treatment of lung carcinoma, with or without laser desobstruction: an improvement in respiratory symptoms was observed in 60 to 80% of the cases; (ii) curative treatment for localised endobronchial carcinomas, in previously irradiated patients, or in case of contraindication of surgery or external beam irradiation; local control rate range from 60 to 70% at 2 years; (iii) combination of external irradiation and brachytherapy in the first line treatment of lung cancers. Two randomised trials did not show any improvement in survival for this approach; however, they have included advanced diseases. In the opposite, this association seems very effective for early stage lung carcinomas. Two major complications were regularly reported, haemoptysis and radiation bronchitis. Predictive factors for these toxicities are actually better known: haemoptysis could be due to a progressive disease more often than to brachytherapy itself; technical factors (dose, volume, fractionation), however, could explain a number of radiation bronchitis, and their incidence could decrease in the future.

Treatment of early stage non-small cell lung cancer

Photodynamic therapy (PDT), brachytherapy, electrocautery, cryotherapy, and Nd-YAG laser therapy are therapeutic options available for management of endobronchial malignancies. All of these treatment modalities have been used for both palliation of late obstructing cancers, and more recently have been used as primary treatment of early radiographically occult cancers. We reviewed the evidence for the use of these treatment options in the management of early lung cancer.

Innovative molecular and imaging approaches for the detection of lung cancer and its precursor lesions

Current approaches for the therapy of lung cancer, the majority of which being advanced cancers, have failed to impact on long term survival. The key to improvement lies in the combination of early diagnosis and the introduction of novel targeted therapies. In this article we review some of the innovative approaches, both imaging and molecular, that are currently under investigation for early detection. Because lung cancers may arise in the central or peripheral compartments of the lung, newer approaches must target tumours arising in both of these compartments. Specimens available for analysis include sputa and blood. Detection of genetic changes in peripheral blood is a promising avenue being explored by several groups. Molecular techniques discussed include gene mutations, detection of nuclear riboprotein, methylation related silencing of genes and malignancy associated changes. Newer imaging technologies include autofluorescence bronchoscopy, virtual bronchoscopy, optical coherent tomography and confocal microscopy. Although the impact of these new technologies on survival has not been determined, they offer a wide range of exciting new approaches. In time they may completely revamp the present highly conservative and unsuccessful approaches to early diagnosis.

Roentgenographically occult bronchogenic squamous cell carcinoma involving mediastinal lymph nodes after removal of initial lesion by the diagnostic examination

A 69-year-old male was suspected of having lung cancer by sputum cytology and diagnosed as roentgenographically occult squamous cell carcinoma (ROSCC) at the spur of left B(1+2)/B(3). However, after the first bronchoscopy, no suspicious lesion was detected by any examinations. Therefore, we considered that cancer cells had been removed completely by the initial examination, and the patient was followed up by sputum cytology, chest roentgenogram, and bronchoscopy. Sixteen months later from the initial examination, bronchoscopy was performed for follow-up. The bronchoscopic findings showed the elevation of the surface of left B(1+2) a+b, but the cytologic specimen by brushing toward B(1+2) a+b showed negative findings. However, the lesion had developed to polypoid-shaped tumor and obstructed B(1+2) a+b after the next 6 months. The tumor was diagnosed as squamous cell carcinoma, and hilar and mediastinal nodal involvement was suspected on chest computed tomography. The standard thoracotomy was performed and the pathological results showed positive for nodal involvement on hilus and mediastinum. The tumor is considered to arise from the residual cancer cells of initially detected ROSCC. In conclusion, although some ROSCCs regress by the diagnostic examinations, it is important to detect the recurrence of residual cancer cells as early as possible by intensive follow-up.

Diagnosis and management of early lung cancer

Bronchogenic carcinoma remains the leading cause of cancer deaths in the United States. Approximately 80% of newly diagnosed cases are non-small cell lung cancer (NSCLC); 80% of these present with disseminated or locally advanced disease. Unfortunately, only 10% are potentially surgically curable patients with early-stage disease (T1N0/T2N0). Most patients with early-stage disease are asymptomatic, with their lung cancer detected as a result of non-cancer related procedures. Studies have shown that chest radiography as a screening modality resulted in a higher discovery of early disease, but did not translate to a significant reduction in lung cancer mortality. Recent work on low-dose helical CT, however, has renewed interest in the challenge of detecting early-stage lung cancer.

Therapy for stage I and stage II non-small cell lung cancer

Despite complete resection of what seems to be all evident tumor, one third to three quarters of patients with stages I and II NSCLC ultimately succumb to this neoplasm. Patients who are cured of an original NSCLC or small cell cancer remain at risk for a new primary lung cancer. Although the importance of lifelong surveillance is clear, the extent and timing of optimal follow-up remain undefined. Although clinicians refer to the development after treatment of clinically discernible sites of tumor as "recurrence," it is probably more accurate to consider these foci as "persistence"--that is, the locoregional site was not sterilized by surgery, and the distant implants were present from the outset but undetected. Although data are sparse, induction and improved adjuvant therapy for early NSCLC may be helpful. Much further experience is needed. Further study and application of biologic indicators in addition to TNM staging likely will help identify patients at high risk for surgical failure who may benefit by combination treatment.

Comorbidity in operable lung cancer: a multicenter descriptive study on 2992 patients

STUDY OBJECTIVES

To ascertain the frequency of diseases associated (comorbidity) with operable lung cancer (LC) globally, in relation to the presence of neoplastic clinical symptoms and age.

DESIGN

Prospective; multi-institutional of 19 Spanish hospitals.

PATIENTS

Two thousand nine hundred and ninety two consecutive cases of LC, treated surgically by the Bronchogenic Carcinoma Co-operative Group of the Spanish Society of Pneumology and Thoracic Surgery (GCCB-S) between 1993 and 1997, are analysed.

METHODS

At time of treatment, data on the presence or absence of different specific comorbidities in all consecutive patients operated on for LC were entered on identical forms at all hospitals of the GCCB-S.

RESULTS

In 2189 patients (73%) there was one or several comorbidities (chronic obstructive pulmonary disease [COPD], systemic arterial hypertension, previous tumour, cardiac disease, peripheral vascular disease or diabetes). Fifty percent of the LC was associated to COPD; in 32% of these patients with COPD, preoperative measurement of FEV1 was 70% below the theoretical value. In comparing the cases with symptoms ascribable to LC, it was found that in asymptomatic patients the presence of a previous tumour, arterial hypertension or cardiac disease was significantly more frequent. Conversely, in symptomatic patients, COPD was significantly more frequent. The frequency of all evaluated comorbidities is significantly higher in the older age groups.

CONCLUSIONS

In this multicenter study encompassing 2992 patients with operable LC, a high frequency of comorbidity has been found, COPD occurring most frequently. Certain diseases are more prevalent in asymptomatic patients, probably due to a screening bias. In older patients, there was a significant increase of all comorbidities.

Diagnostic dilemmas in pulmonary cytology

BACKGROUND

Diagnostic difficulties in pulmonary cytology may be compounded by other medical problems, lack of pertinent information, and the presence of rare tumors. In the current study, the authors describe six cases of lower respiratory tract cytology that presented particular diagnostic challenges or pitfalls.

METHODS

Three lung fine-needle aspiration biopsies (FNAB) from three patients, four bronchoalveolar lavages from two patients, and one bronchial washing from one patient, each with histologic confirmation, were reviewed. Cytologic material included direct smears, ThinPrep slides, and cell blocks. Cytologic findings were compared with established cytologic criteria for each final diagnosis.

RESULTS

Two cases with Aspergillus infection that demonstrated reactive atypical cells were misinterpreted as squamous cell carcinoma and nonsmall cell carcinoma. Two cases diagnosed as significant atypia and negative, respectively, subsequently were found to show bronchioloalveolar carcinoma (as well as lymphangioleiomyomatosis, which was suspected clinically) and bronchogenic adenocarcinoma, respectively. One lung FNAB from a patient subsequently confirmed to have bronchiolitis obliterans-organizing pneumonia (BOOP) showed reactive pneumocytes that initially were misinterpreted as being suspicious for carcinoid. These reactive pneumocytes were identified histologically in the area of BOOP. The last case was an FNAB of a well differentiated fetal-type adenocarcinoma, an unusual variant of adenocarcinoma that to the authors' knowledge rarely is described in the cytology literature.

CONCLUSIONS

Cytomorphologic features of lower respiratory tract pathology combined with appropriate clinical information and diagnostic discretion usually allow accurate diagnoses and should decrease both false-positive and false-negative result rates. Clinical information and radiologic findings may be invaluable, but may not always parallel the cytologic diagnosis.

Fluorescence versus white-light bronchoscopy for detection of preneoplastic lesions: a randomized study

BACKGROUND

There are no currently approved methods for the screening and early detection of lung cancer. We compared the ability of conventional white-light bronchoscopy (WLB) and laser-induced fluorescence endoscopy (LIFE) to detect preneoplastic lung lesions in a randomized trial in which both the order of the procedures and the bronchoscopists were randomly assigned.

METHODS

The study included high-risk subjects enrolled because of a cigarette smoking history of at least 30 pack-years, an air-flow obstruction, and either an abnormal sputum cytology (n = 48) or a previous or suspected lung cancer (n = 7). LIFE and WLB were performed on all patients. Biopsy specimens were assessed for histologic abnormalities, including the presence of angiogenic squamous dysplasia. All statistical tests were two-sided.

RESULTS

A total of 391 biopsy specimens were taken from the 55 patients. Thirty-two patients (58%; 95% confidence interval [CI] = 44% to 71%) had at least one biopsy with moderate or severe dysplasia, and 19 (59%; 95% CI = 41% to 76%) of these patients could be diagnosed based solely on the results of LIFE. LIFE was statistically significantly more sensitive than WLB for detecting moderate dysplasia or worse (68.8% versus 21.9%, respectively) (difference = 46.9%; 95% CI = 25% to 68%; P< .001). The relative sensitivities (WLB = 1.0) were 3.1 (95% CI = 1.6 to 6.3) for LIFE and 3.7 (95% CI = 1.9 to 7.3) for LIFE and WLB combined. LIFE was less specific than WLB (69.6% versus 78.3%, respectively; P = .45), but the difference was not statistically significant. The relative specificities (WLB = 1.0) were 0.9 for LIFE (95% CI = 0.6 to 1.3) and 0.6 (95% CI = 0.4 to 1.0) for LIFE and WLB combined. The results were similar regardless of the order of the procedures or the order of the bronchoscopists. Also, LIFE was better at identifying angiogenic squamous dysplasia lesions than WLB (detection ratio [DR], which indicates the relative likelihood of getting a positive result in a sample with dysplasia compared with one without, for LIFE = 1.39 [95% CI = 1.17 to 1.65] versus DR for WLB = 0.67 [95% CI = 0.38 to 1.21]).

CONCLUSION

LIFE was more sensitive than WLB in detecting preneoplastic bronchial changes in high-risk subjects. The prognostic implication of this finding is not yet clear.

Cryotherapy in early superficial bronchogenic carcinoma

BACKGROUND

Treatment of early superficial bronchogenic carcinoma (ESBC) is under debate, and no consensus has been achieved. Different therapeutic methods have been proposed, including surgical resection and endoscopic methods.

STUDY OBJECTIVE

To assess the efficacy of cryotherapy in patients with ESBC.

PATIENTS AND METHODS

Patients included in the study had histologically proven ESBC after fiberoptic bronchoscopy. Cryotherapy was performed through a rigid bronchoscope. Efficacy was assessed by endoscopy with multiple biopsies 1 month after treatment and during the follow-up period. Parameters studied were response to treatment, adverse effects, and survival.

RESULTS

We included 35 patients (34 men and 1 woman). The mean age was 61 +/- 9 years. Multiple locations of ESBC were observed in seven patients (20%). Complete response rate at both 1 month and 1 year was 91% (32 patients). No severe adverse effects were noted. Local recurrence was observed within 4 years in 10 patients (28%). A follow-up period of at least 4 years was available in 22 patients; of them, 11 patients (50%) were long-term survivors.

CONCLUSION

Our results suggest that cryotherapy is an effective method of treatment in patients with ESBC. Due to its relative tolerance compared to surgery, cryotherapy could be proposed as a first-line therapy in this population with high carcinogenic risk.

Endoscopic evaluation of centrally located early squamous cell carcinoma of the lung

BACKGROUND

Lung-sparing treatment recently has become a choice in the treatment of patients with early hilar lung carcinoma. To select the method of treatment, it is important to evaluate the histologic extent of the tumor using endoscopy.

METHODS

A total of 46 patients who underwent surgery for an endoscopically evaluated early lung carcinoma of the tracheobronchial tree were analyzed. Initial surgery was performed in 16 patients and in 30 patients surgery was performed after preoperative laser therapy. The endoscopic findings were classified into three types: superficial, nodular, and polypoid. In the resected lung, the greatest tumor dimension, the depth of mural invasion, the presence of microscopic blood and lymph vessel invasion, and metastases to the dissected lymph nodes were examined.

RESULTS

The mean greatest tumor dimensions were 14.6 +/- 7.3 mm (mean +/- standard deviation) in the nodular group, 23.3 +/- 12.8 mm in the superficial group, and 19.0 +/- 9.2 mm in the polypoid group. The greatest tumor dimension in the superficial group was significantly larger than that in the nodular group (P < 0.01). Preoperative endoscopic diagnosis of early hilar lung carcinoma was correct histologically in 34 of 46 cases (74.0%). Hilar lymph node metastases (N1), extrabronchial invasion, and extension to the peripheral bronchus were recognized in 12 cases. Complete disappearance of the tumor due to preoperative laser therapy was confirmed in eight patients. Lymph node metastasis was not found when the greatest tumor dimension measured < 8 mm. The overall absolute 5-year survival rate was 76.0% for all patients, 87.1% for the surgery alone group, and 70.0% for the surgery after preoperative laser therapy group.

CONCLUSIONS

Curative treatment of early hilar lung carcinoma is possible using photodynamic therapy alone when the tumor size is < or = 8 mm and the lesion does not extend to the peripheral bronchus.

External irradiation and intraluminal irradiation using middle-dose-rate iridium in patients with roentgenographically occult lung cancer

PURPOSE

Therapeutic results were analyzed in 39 patients with roentgenographically occult lung cancer (ROLC), and the significance and optimal dose of this therapy were evaluated.

METHODS AND MATERIALS

The subjects were 39 patients who underwent intraluminal irradiation between May 1987 and August 1999. Radiotherapy was performed by combining external irradiation with intraluminal irradiation using middle-dose-rate iridium (four 370-MBq wires) through a catheter with a spacer, which held the source in the center of the bronchus. The doses of radiation were 22-66 Gy (median value 45 Gy) by external irradiation and 10-46 Gy (median value 28 Gy) by intraluminal irradiation.

RESULTS

The therapeutic effect was CR in 38 patients and PR in 1, and local recurrence was observed in a PR case and 3 of the 38 patients who showed CR. The 3-year and 5-year relapse-free survival rates were both 87%. No severe radiation injury was observed.

CONCLUSIONS

Considering that ROLC often occurs as multiple cancers and that many patients with ROLC have reduced lung function, radiation therapy by a combination of intraluminal irradiation and external irradiation is expected to replace surgery as the first choice for the treatment of this disease in the twenty-first century.

Bronchoscopically-guided conformal radiation therapy for radiographically occult lung carcinoma

Radiographically occult lung carcinoma has a very good prognosis after complete surgical resection. In medically inoperable patients three-dimensional conformal radiation therapy cannot be performed, as computed tomography scan images fail to localize the disease. Presented here is an original technique of marking radiographically occult tumors by fiberoptic bronchoscopy, applied on four patients. No short-term complications were recorded. All the patients are alive, with no evidence of disease, after a mean follow-up of 15 months.

Contemporary role of modern brachytherapy techniques in the management of malignant thoracic tumors

Sole brachytherapy for carcinoma of the lung is most often performed using high-dose-rate (HDR) remote afterloading equipment, which delivers the treatment within the tracheobronchial tree in an outpatient setting. It provides excellent, rapid palliation in advanced stages, and can also be used selectively for curative intent in early stages. In better-performance patients, fractionated external beam radiation therapy (EBRT) is preferred to brachytherapy as an initial treatment because it appears to provide a modest gain in survival, and more sustained palliation. In patients with centrally located tumors and limited extent of disease, the combination of external and endoluminal irradiation enables curative treatment options. Intraoperative brachytherapy may complement standard adjuvant treatment in incompletely resected, unresectable, or medically inoperable patients, and has the potential to improve local control in selected cases. Due to the rarity of the disease, the role of endoluminal brachytherapy in the treatment regimen of tracheal neoplasms is not yet clearly defined. The risk of fatal bleeding after endoluminal brachytherapy appears to be correlated with tumor localization and fraction size, but in the majority of cases fatal bleeds are caused by progression of local disease. The use of a distanceable applicator provides a central positioning of the source, prevents the delivery of high-contact doses to the mucosa, and may reduce toxicity. The standard technique for interstitial brachytherapy after breast-conserving surgery and adjuvant EBRT is the use of low-dose-rate (LDR) brachytherapy, but it may also be applied by means of pulsed-dose-rate (PDR) or HDR techniques. Prospective trials comparing different boost techniques and indications are needed to define more precisely the subgroup of patients who are most suitable for interstitial brachytherapy. Reirradiation of chest wall local recurrences using brachytherapy molds is effective and provides a high local control rate with acceptable toxicity.

Surgical results for centrally-located early stage lung cancer

BACKGROUND

With the increasing use of mass screening programs for lung cancer, and especially the use of sputum cytology, the incidence of roentgenographically occult lung cancer has been increasing. These occult cancers comprise mainly histologically centrally-located early stage lung cancers. This study examined the clinicopathologic characteristics and surgical results of centrally-located early stage lung cancer.

RESULTS

From 1980 to 1998, there were 98 patients and 99 lesions of centrally-located early stage lung cancer resected. A total of 64 patients were detected by mass screening. Histologic examination revealed that 96 lesions were squamous cell carcinoma, and in these patients, there were 10 lesions of carcinoma in situ. The 5-year survival rate was 81.4% in all patients, and 88.9% in carcinoma in situ patients. In the postoperative follow-up period, a second lung cancer occurred in 13 patients.

CONCLUSIONS

The surgical results for centrally-located early lung cancer were good. However, sometimes these cancers are accompanied by a second centrally-located primary lung cancer, so it is necessary to follow-up with sputum cytology to allow early detection of additional centrally-located lung cancer.

Fluorescence bronchoscopic surveillance after curative surgical resection for non-small-cell lung cancer

BACKGROUND

Second lung primaries occur at a rate of up to 3% per patient-year after curative resection for non-small-cell lung carcinoma. Postresection patients are often poor candidates for further curative surgery because of their diminished pulmonary reserve. The aim of this study was to evaluate the role of fluorescence bronchoscopy by using the Xillix LIFE-Lung Fluorescence Endoscopy System to identify second lung primaries in patients who have had a previous curative resection of a non-small-cell lung cancer.

METHODS

Patients who had no evidence of disease status after resection of a non-small-cell lung cancer were identified from a prospectively collected data base and entered onto a fluorescence bronchoscopy surveillance protocol. All suspicious areas, as well as several areas of apparently normal mucosa, were sampled for biopsy. A single pathologist reviewed all biopsy specimens, with 10% of biopsies re-reviewed, for quality control, by a second pulmonary pathologist.

RESULTS

A total of 31 surveillance fluorescence bronchoscopies were performed on 25 patients after conventional bronchoscopy. Four intraepithelial neoplasias or invasive carcinomas were identified in 3 (12%) of 25 patients screened. The addition of the LIFE examination to conventional bronchoscopy increased the sensitivity of screening from 25.0% to 75.0%, which yielded a relative sensitivity of 300% with a negative predictive value of .97.

CONCLUSIONS

Use of postresection surveillance with fluorescence bronchoscopy identified intraepithelial or invasive lesions in 12% of non-small-cell lung cancer patients, and the system was three times more sensitive than conventional bronchoscopy to identify these early mucosal lesions. Fluorescence bronchoscopic surveillance of this high-risk, postresection population will help better define the true rate of occurrence and the natural history of second primaries and may assist in monitoring their response to newer, noninvasive treatment methods, such as photodynamic therapy or chemopreventive agents, in future trials.

Synchronous roentgenographically occult lung carcinoma in patients with resectable primary lung cancer

OBJECTIVE

To assess the prevalence of synchronous roentgenographically occult lung carcinoma (ROLC) in patients with resectable roentgenographically visible lung cancer (RVLC).

METHODS

Patients undergoing surgery for RVLC in the same University Hospital were prospectively evaluated before surgery by fluorescence bronchoscopy under local anesthesia to detect synchronous ROLC. All abnormal areas, with the exception of the RVLC, had biopsies made.

RESULTS

From June 1996 to January 1999, 43 patients (male/female ratio: 1.7/1.0) were evaluated before lobectomy (n = 34) or pneumonectomy (n = 10) for 44 primary RVLC. There were 10 T1N0, 19 T2N0, 1 T1N1, 9 T2N1, 1 T3N0, 3 T1N2, and 1 T3N1 lesions. The histologic type was mainly squamous carcinoma (n = 21) and adenocarcinoma (n = 14). All but two patients were smokers or ex-smokers (mean +/- SD, 48 +/- 28 pack-years). A total of 177 endobronchial biopsies were performed (4.1 +/- 2.5); 8 were too small to be informative, 43 showed non-preneoplastic alterations, and 50 were normal. There were 7 basal cell hyperplasias, 56 metaplasias, 9 dysplasias, and 4 carcinomas in situ (CIS). All the dysplasias and CIS lesions were observed in eight subjects. The synchronous CIS were treated by surgery (n = 1) or localized therapeutic modalities (n = 3).

CONCLUSIONS

The high prevalence of synchronous early lung cancers (9.3%) as well as metaplasia and dysplasia in this series of patients with resectable RVLC suggests that fluorescence bronchoscopy may be a useful adjunct in the preoperative evaluation of lung cancer.

Pathology of lung cancer

Microscopic examination of stained smears and tissue sections remains the standard method for definitive diagnosis and classification of lung cancer. However, the morphology of lung cancer is complex, and consensus classifications such as those prepared by a panel World Health Organization (WHO) are required for the sake of consistency and clinical relevance. In the most recent (1999) WHO classification, the diagnostic categories of greatest clinical importance, small cell lung carcinoma and non-small cell lung carcinoma, remain fundamentally unchanged. However, application of immunohistochemistry and electron microscopy has revealed expression of neuroendocrine markers in a wide variety of tumors. Expression of these markers is not taken into account in current treatment protocols, and additional correlative studies will be required to determine the clinical relevance of neuroendocrine differentiation in lung carcinoma. In addition to histological classification, microscopic analysis can provide in situ evidence of response to chemotherapy, as well as information on precursor lesions and multistep carcinogenesis in the airways. Finally, it is likely that morphological assessment of lung carcinoma and preneoplastic lesions will continue to be refined as new diagnostic modalities such as spiral computed tomography and fluorescence bronchoscopy provide previously inaccessible specimens for morphological and correlative molecular studies.

Radiation therapy for roentogenographically occult lung cancer by external beam irradiation and endobronchial high dose rate brachytherapy

PURPOSE

We investigated the clinical usefulness of radiation therapy by external beam irradiation and endobronchial brachytherapy for the treatment of roentogenographically occult lung cancer.

PATIENTS AND METHODS

From 1995 to 1996, five patients were treated with radiation therapy. We analyzed their treatment outcomes. The follow-up period varied from 3.0 to 3.8 years or until death. External beam radiation (40 Gy/20 fractions/4 weeks) was delivered to the tumor site alone, and not prophylactically given to the mediastinum. Endobronchial brachytherapy using high dose rate iridium (Ir)-192 was concurrently administered principally to a total dose of 18 Gy on the bronchial mucosa in three weekly fractions of 6 Gy each.

RESULTS

Complete remission was obtained in all patients. Two patients died of intercurrent diseases at 12 and 21 months without any evidence of recurrence. The disease has been also controlled in the other three cases. With the above doses, three small tumors < 1 cm were controlled without adverse effect. In two tumors, the dose reference points were set 2-7 mm beneath the mucosa, and larger doses were administered by brachytherapy. An applicator acting as a spacer was not used in these cases. The tumors were controlled, although the irradiated bronchi showed severe stenosis in 6 months following the treatment. However, the patients were asymptomatic and did not need further intervention.

CONCLUSION

External beam irradiation combined with endobronchial brachytherapy was useful for the treatment of roentogenographically occult lung cancer as an alternative to surgery. Further investigation is needed to determine the optimal doses of radiation therapy.