Bronchoalveolar carcinoma: histopathologic study of evolution in a series of 105 surgically treated patients

An elderly male with nonresolving consolidation

An 81-year-old male presented with a background history of progressive shortness of breath for 3 years with recent worsening in the past 6 months. Clinicoradiological investigations were consistent with a nonresolving consolidation involving predominantly right lung. This clinicopathologic conference discusses the differential diagnoses of pneumonia of long-standing duration and their management options.

Recurrent Pneumonia? A Case of Availability Bias and Anchoring

Invasive mucinous adenocarcinoma is a multi-centric adenocarcinoma that accounts for less than 5% of all lung cancer diagnoses. The most common presenting symptoms (cough, sputum production, and chest pain) in conjunction with its radiographic findings (patchy, multi-lobar infiltrates) make invasive mucinous adenocarcinoma challenging to distinguish from both infectious and inflammatory pneumonia. However, due to its aggressive nature, invasive mucinous adenocarcinoma should be considered if a presumed case of pneumonia lacks symptoms of infection (e.g., fever, leukocytosis) and/or does not respond to antibiotics. We report the case of a 75-year-old male who was admitted in the setting of a presumed case of recurrent pneumonia, which had failed to respond to prior antibiotic therapy. Further workup, including trans-bronchial biopsy, confirmed mucinous adenocarcinoma with a lepidic pattern. This case highlights the importance of establishing a broad differential in the setting of unresolved pneumonia following appropriate antibiotic coverage.

Nonresolving pneumonia in the setting of malignancy

PURPOSE OF REVIEW

This article reviews recent literature and experience in the diagnosis of nonresolving and slowly resolving pneumonia as it pertains to malignancy.

RECENT FINDINGS

Malignancy must be considered as an important cause of pneumonia that resolves slowly or has incomplete resolution. Airway obstruction is more common than malignant infiltration as a cause of pneumonia that does not resolve appropriately. Infection due to resistant or unusual organisms must also be considered in the differential diagnosis.

SUMMARY

Nonresolving pneumonia remains an important clinical challenge. Bronchoscopic evaluation in conjunction with computed tomography and PET scanning is still the most important technique for diagnosis.

Clinical characteristics and prognosis of nonsurgically treated patients with pneumonic-type adenocarcinoma

Pneumonic-type adenocarcinoma (P-ADC) is a subtype of lung adenocarcinoma with high mortality, which often requires lobectomy surgery. Nonsurgically treated P-ADC patients usually have more advanced or complex conditions, which remain poorly understood and pose a major challenge in clinical management. We aimed to describe the clinical profiles and prognosis of non-surgically treated P-ADC patients. We enrolled 71 patients with pathologically proven P-ADC from a university hospital in China. Clinical and laboratory data were retrieved from medical record. Their median age was 62 years, including 45% men and 35% smokers. Clinical manifestations were dominated by cough, sputum, and dyspnea. Main chest imaging features included nodules, shadow, consolidation, and air bronchogram. Nearly half or more of patients showed higher levels of inflammation and cancer biomarkers including cytokeratin-19-fragment (CYFRA 21-1) and carcinoembryonic antigen (CEA). Majority of patients were classified at the stage IIIB or IV. Palliative care was the most popular treatment option but provided a shorter overall survival compared to tyrosine kinase inhibitor therapy, standard chemotherapy, and sequential therapy while there were no significant differences in the survival among the latter 3 options. Higher serum CEA was associated with longer survival and better prognosis while higher serum CYFRA 21-1 could predict a poor prognosis. Detailed understanding the clinical characteristics and prognostic factors in nonsurgically treated P-ADC may allow the identification of patients with particular risk factors and initiation of early and specific treatment in order to optimize outcomes.

Use of Oncogenic Driver Mutations in Staging of Multiple Primary Lung Carcinomas: A Single-Center Experience

OBJECTIVE

The staging of multiple pulmonary adenocarcinomas requires the distinction of intrapulmonary metastasis (IPM) from multiple primary lung cancers (MPLCs). This can be challenging in some patients, and the addition of data from oncogenic driver mutations in these tumors may be helpful in this determination.

METHODS

As a proof of principle, molecular driver results from primary tumors and their metastases in 45 patients were compared (cohort 1). Then, 69 patients with a total of 154 synchronous or metachronous lung carcinomas were identified, and the pathologic findings were compared with oncogenic driver mutation. Each patient was assigned a highest potential T or M category on the basis of clinical, histopathologic, and molecular findings (cohort 2).

RESULTS

The concordance rate of EGFR, KRAS, BRAF, and ALK receptor tyrosine kinase gene (ALK) mutations was 96% in cohort 1. In cohort 2, 36% of multiple same-lobe nodules were MPLCs, 40% were IPM, and 24% were noninformative by molecular findings. Of nodules with multiple lobe involvement, 81.5% were MPLCs and 7.4% were IPM, with 11% noninformative. Of metachronous tumors, 52.9% were MPLCs. Overall survival was 100% at 2 years, 95% at 3 years, and 80% at 4 years in patients with available follow-up.

CONCLUSIONS

Oncogenic driver mutations are concordant between primary tumors and metastasis. The largest proportion of MPLCs was seen in tumors of multiple lobes, but with a substantial proportion of MPLCs among single-lobe nodules and with metachronous tumors. Overall survival was higher than expected for the respective highest T or M category, which is in support of the high frequency of MPLC.

Clinical implications of genetic heterogeneity in multifocal pulmonary adenocarcinomas

Multifocal pulmonary adenocarcinomas are increasingly encountered in clinical practice, in part due to the increased availability and improvement in the thoracic imaging. Recognized as a distinct entity in the upcoming 8^th edition of American Joint Commission on Cancer (AJCC) staging system, multifocal adenocarcinomas exhibit several unique features such as the characteristic appearance of multiple ground glass opacities or nodules in computerized tomography (CT). Recent studies have suggested that the vast majority of these malignant lesions are genetically independent even when occurring synchronously in a single patient. For instance, the pattern of epidermal growth factor receptor (EGFR) mutations in multifocal pulmonary adenocarcinomas can vary from one lesion to another. This observation has several important clinical implications. These include the potential need to perform multiple molecular tests on multiple lesions, the possible role of molecular marker such as EGFR mutation in the staging of questionable multiple lung cancers, and the justification for empirical use EGFR inhibitors for multifocal adenocarcinomas among high-prevalence population when no known mutation has been detected.

Clinical course of stage IV invasive mucinous adenocarcinoma of the lung

INTRODUCTION

An invasive mucinous adenocarcinoma (IMA) is a distinct lung adenocarcinoma variant. The characteristics of stage IV IMAs are relatively unclear since most previous studies described resected cases from stage I to III. The present study aimed to investigate the clinical course of stage IV IMAs and compare the findings to those of stage IV invasive non-mucinous adenocarcinomas (INMAs).

METHODS

The study included 36 IMA patients and 210 INMA patients. The clinicopathological parameters, treatment methods and responses, overall survival (OS), and progression-free survival (PFS) were evaluated.

RESULTS

IMAs were predominantly located in the lower lobes and frequently presented with multifocal consolidation and lung-to-lung or pleural metastasis. KRAS mutations were noted in 60.0% of the examined IMAs. Non-TKI chemotherapy (CTx) was used in 72.2% of the IMA patients. OS was significantly better in untreated IMA patients than in untreated INMA patients. IMA patients treated with non-TKI CTx had no improvement of OS compared to the untreated IMA patients. However, among INMA patients, OS was best with TKIs in patients harbouring targetable mutations, followed by non-TKI CTx. IMA and INMA patients treated with non-TKI CTx had similar PFS.

CONCLUSIONS

Stage IV IMAs have distinct clinicopathological characteristics, and they might be less aggressive than INMAs. Since non-TKI CTx might not be beneficial in IMA patients, new therapeutic approach is necessary.

Recurrent "pneumonia" in left lower lobe lasting for 8 years: a case report

Bronchioloalveolar carcinoma (BAC) is a unique lung neoplasm with variable forms, such as single nodular, multifocal and lobar pneumonic types. The pneumonic type BAC is often difficult to differentiate from pneumonia. Here we present a case of 63-year-old Chinese male, who had recurrent cough, white sputum with pneumonic lesions in left lower lobe. He suffered from lung biopsies for three times, and finally diagnosed as high differentiated adenocarcinoma 8 years later. He was treated with four cycles of pemetrexed and cisplatin, and four cycles of docetaxel and nedaplatin. However, he did not achieve disease stabilization and is still under follow up. This case suggests that, pneumonic type adenocarcinoma may radiographically and clinically resemble infectious pneumonia. Lack of fever and leukocytosis, no response to antibiotics, air bronchogram, and accompanied nodules or patches in computed tomography (CT) scans should raise suspicion about the diagnosis of pneumonia. Lung biopsy might be the only means of ruling in a diagnosis of BAC.

The IASLC Lung Cancer Staging Project: Background Data and Proposals for the Application of TNM Staging Rules to Lung Cancer Presenting as Multiple Nodules with Ground Glass or Lepidic Features or a Pneumonic Type of Involvement in the Forthcoming Eighth Edition of the TNM Classification

INTRODUCTION

Application of tumor, node, and metastasis (TNM) classification is difficult in patients with lung cancer presenting as multiple ground glass nodules or with diffuse pneumonic-type involvement. Clarification of how to do this is needed for the forthcoming eighth edition of TNM classification.

METHODS

A subcommittee of the International Association for the Study of Lung Cancer Staging and Prognostic Factors Committee conducted a systematic literature review to build an evidence base regarding such tumors. An iterative process that included an extended workgroup was used to develop proposals for TNM classification.

RESULTS

Patients with multiple tumors with a prominent ground glass component on imaging or lepidic component on microscopy are being seen with increasing frequency. These tumors are associated with good survival after resection and a decreased propensity for nodal and extrathoracic metastases. Diffuse pneumonic-type involvement in the lung is associated with a worse prognosis, but also with a decreased propensity for nodal and distant metastases.

CONCLUSION

For multifocal ground glass/lepidic tumors, we propose that the T category be determined by the highest T lesion, with either the number of tumors or m in parentheses to denote the multifocal nature, and that a single N and M category be used for all the lesions collectively-for example, T1a(3)N0M0 or T1b(m)N0M0. For diffuse pneumonic-type lung cancer we propose that the T category be designated by size (or T3) if in one lobe, as T4 if involving an ipsilateral different lobe, or as M1a if contralateral and that a single N and M category be used for all pulmonary areas of involvement.

The impact of intracytoplasmic mucin in lung adenocarcinoma with pneumonic radiological presentation

OBJECTIVES

This study investigated the clinical and prognostic impact of intracytoplasmic mucin in lung adenocarcinoma with "pneumonic" radiological presentation, formerly known as bronchioloalveolar carcinoma (BAC).

PATIENTS AND METHODS

Between 1986 and 2011, clinical and pathological data from 120 consecutive patients with lung adenocarcinoma with "pneumonic" radiological presentation were reviewed. Intracytoplasmic mucin was assessed using a diastase-resistant periodic acid-Schiff staining. The presence of EGFR or K-Ras mutations and ALK rearrangement were determined in surgical samples.

RESULTS

The two predominant histological patterns were invasive mucinous adenocarcinoma (40%) and lepidic predominant adenocarcinoma (32%). Intracytoplasmic mucin was detected in 71 patients (59.2%) who were more likely to be non-smokers (p=0.04) and have bronchorrhea (p=0.006), crepitant rales (p=0.02), or neutrophil alveolitis (p=0.0004). In mucin-producing tumors, EGFR mutation was not detected, K-Ras mutations and ALK rearrangement were present in 32% and 3% of cases, respectively. In non-mucin-producing tumors, EGFR and K-Ras mutations were detected in 17% and 10% of cases, respectively, no ALK rearrangement was detected. In univariate analysis, performance status>0, crepitant rales, bronchorrhea, neutrophil alveolitis, bilateral extension, intracytoplasmic mucin and no surgery were associated with worse survival. In multivariate analyses, intracytoplasmic mucin, neutrophil alveolitis, and no surgery were independent factors for worse survival.

CONCLUSION

Intracytoplasmic mucin is associated with specific clinical characteristics and is an independent factor for worse survival in lung adenocarcinoma formerly known as BAC.

'Non-resolving' pneumonia

A 47-year-old man presented with symptoms of fever and productive cough secondary to a left upper lobe pneumonia. He had received more than three courses of antibiotics over a 2-year period. Review of serial radiographic exams including chest x-ray and CT scans revealed consolidation of the left upper lobe. Lack of response to antibiotics prompted invasive testing with bronchoscopy which revealed a growth in the left main bronchus. Histopathology revealed squamous cell carcinoma.

Surgical resection for patients with mucinous bronchioloalveolar carcinoma

BACKGROUND

The clinical features of mucinous bronchioloalveolar carcinoma (BAC) have remained unclear due to the low incidence of this disease. This study investigated the clinicopathological features and the surgical outcome in patients with mucinous BAC.

METHODS

We clinicopathologically evaluated 782 patients who underwent resection for nonsmall cell carcinoma between 1999 and 2008, of whom, 13 (1.6%) demonstrated to have mucinous BAC.

RESULTS

The patients with mucinous BAC included six men and seven women. The mean age was 69.1 years (range: 55-78 years). Eight patients (61.5%) had a smoking habit. No patients had any subjective symptoms. The tumour diameter ranged from 1.2 cm to 10 cm. The surgical procedures included 11 lobectomies, and two partial resections of affected lobes. The pathological stage was IA in eight patients, IB in two, IIA in two, and IIIA in one. None of the patients had lymph node metastases or lymphovascular invasion. The overall postoperative 5-year survival rate was 52.5%. The 5-year survival rate according to tumour diameter was 100% in patients with tumours ≤ 3 cm, and 25.1% in patients with tumours > 3 cm. Two patients died due to pulmonary metastases, and one died from carcinomatous pleuritis and pulmonary metastases.

CONCLUSION

Patients with small mucinous BAC (≤ 3 cm) in diameter showed excellent prognosis after surgical resection. However, mucinous BAC > 3 cm in diameter tended to recur with pulmonary metastasis.

Lung cancer with localized ground-glass attenuation represents early-stage adenocarcinoma in nonsmokers

BACKGROUND

Studies of lung cancer showing localized ground-glass attenuation (GGA) on thin-section computed tomography (TSCT) have been limited to resected stage IA adenocarcinomas. This study aimed to clarify the features of localized GGA cancer as a distinct clinicoradiological entity through a survey of lung cancers of all types.

METHODS

From 2000 through 2002, 492 patients with newly diagnosed stage I-IV lung cancer underwent TSCT at a single institution. The tumors were semiquantitatively classified into four groups on the basis of GGA area as a percentage of the whole tumor shadow (GGA ratio) on TSCT images: 100%, 99-50%, 49-1%, and 0%. The relationship between clinicopathological data and the GGA ratio, predictors of the presence of GGA, survival data, and prognostic factors were evaluated retrospectively.

RESULTS

All localized GGA cancers were adenocarcinomas (p < 0.05). A GGA component was not found in patients with advanced cancer (p < 0.05). GGA cancer was related to nonsmoking status (Odds ratio 6.17, p < 0.05). A threshold tumor size of 30 mm in GGA cancer (hazard ratio, 2.86; p < 0.01) and the GGA ratio (hazard ratio, 4.17; p < 0.01) were independent prognostic factors. Survival rates were higher in patients with a GGA ratio > or = 50% and stage IB lung cancer than in patients with a GGA ratio < 50% and stage IA lung cancer.

CONCLUSION

Localized GGA cancer, with presurgical prognostic factors of tumor size and GGA ratio, represents early-stage lung adenocarcinoma in nonsmokers.

Efficacy of thoracoscopic resection for multifocal bronchioloalveolar carcinoma showing pure ground-glass opacities of 20 mm or less in diameter

OBJECTIVE

Small bronchioloalveolar carcinoma showing pure ground-glass opacity on high-resolution computed tomographic scans is commonly multifocal. Surgical treatment for these lesions is controversial. We discuss the efficacy of video-assisted thoracic surgery for multifocal bronchioloalveolar carcinoma in patients at our institution.

METHODS

Twenty-seven patients with multifocal bronchioloalveolar carcinoma lesions less than or equal to 20 mm in diameter (105 lesions) underwent video-assisted thoracic surgery pulmonary resection between 2000 and 2006. Their clinicopathologic features were investigated retrospectively.

RESULTS

Twenty-seven patients (10 male and 17 female) with a median age of 64 years (range, 41-78 years) had 91 ground-glass opacity lesions on high-resolution computed tomography. Sixteen patients (59%) were women with no history of smoking. The distribution of bronchioloalveolar carcinoma lesions was unilateral in 14 patients and bilateral in 13 patients. Ten patients underwent wedge resection. Seventeen patients underwent single-stage segmentectomy or lobectomy (alone or with wedge resection) for technical reasons. All lesions were completely resected. One patient underwent conversion to thoracotomy for bleeding. Histologic diagnoses showed 62 bronchioloalveolar carcinoma type A lesions, 28 type B lesions, and 15 type C lesions according to Noguchi's classification, and atypical adenomatous hyperplasia in 43 lesions (13 patients). All patients had N0 disease. The median postoperative observation period was 46 months. All patients have survived to date, but new lesions have developed in 7 (26%). Patients with new lesions had a higher incidence of bronchioloalveolar carcinoma lesions of 3 mm or less in diameter (P = .0254) and atypical adenomatous hyperplasia (P = .011).

CONCLUSION

Video-assisted thoracic surgery management of multifocal bronchioloalveolar carcinoma yielded satisfactory results. However, the appearance of new lesions remains a problem.

Diagnostic surgical pathology in lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition)

OBJECTIVE

The objective of this study was to provide evidence-based background and recommendations for the development of American College of Chest Physicians guidelines for the diagnosis and management of lung cancer.

METHODS

A systematic search of the medical and scientific literature using MEDLINE, MDCONSULT, UpToDate, Cochrane Library, NCCN guidelines, and NCI/NIH search engines was performed for the years 1990 to 2006 to identify evidence-based and consensus guidelines. The search was limited to literature on humans and articles in the English language.

RESULTS

The pathologic assessment of lung cancers is based on a set of well-accepted findings, including histologic type, tumor size and location, involvement of visceral pleura, and extension to regional and distant lymph nodes and organs. Bronchial-based incipient neoplasia needs to be recognized both grossly and microscopically because these lesions may be multifocal and represent multistep carcinogenesis and may be amenable to therapy. Cytologic assessment of the individual with no symptoms is, as yet, of insufficient clinical benefit for screening of lung cancer. In challenging situations of pathologic differential diagnosis, additional studies may provide information that enables the separation of distinct tumor types. Pathobiological and molecular biological studies may yield prognostic and predictive information for clinical management and should be considered as part of protocol studies. Enhanced pathologic and molecular techniques may identify the presence of micrometastatic disease within lymph nodes; however, the clinical utility of these approaches is still unresolved. Intraoperative consultations have high diagnostic accuracy and may aid ongoing treatment and management decisions.

CONCLUSIONS

Pathologic assessment is a crucial component for the diagnosis, management, and prognosis of lung cancer. Selective diagnostic techniques and decision analysis will increase diagnostic accuracy. Cytologic screening, molecular characterization of tumors, and micrometastatic analysis are potential but not yet proved modalities for the evaluation of lung cancers.

Tumor fluoro-2-deoxy-D-glucose avidity on positron emission tomographic scan predicts mortality in patients with early-stage pure and mixed bronchioloalveolar carcinoma

OBJECTIVE

Bronchioloalveolar carcinoma is a clinically heterogeneous subtype of non-small cell lung carcinoma that frequently has low 2-[18F]fluoro-D-glucose (FDG) uptake on positron emission tomographic scanning. We investigated whether tumor FDG avidity was associated with worse survival among patients with completely resected node-negative pure and mixed bronchioloalveolar carcinoma.

METHODS

We performed a cohort study of 36 patients who had completely resected pure and mixed bronchioloalveolar carcinoma between 1998 and 2004, who had no hilar or mediastinal lymph node metastases, and who had undergone a preoperative positron emission tomographic scan. Tumor FDG avidity was defined as a standardized uptake value of 2.5 or greater. Survival analysis was performed with a proportional hazards model.

RESULTS

Of 36 patients studied, 26 patients (72%) were alive and 10 patients (28%) were dead after a median follow-up of 31 months (interquartile range 17-41 months). Seventeen patients (47%) had FDG-avid tumors, and 19 patients (53%) had non-avid tumors. Three-year survival was 49% in the FDG-avid group and 95% in the non-avid group (P = .005). FDG avidity had a hazard ratio of death of 8.6 (95% confidence interval 1.4-244.7, P = .02) after adjusting for tumor size, the presence of multifocal bronchioloalveolar carcinoma, and the presence of histologically mixed bronchioloalveolar carcinoma.

CONCLUSIONS

Preoperative tumor FDG standardized uptake value of 2.5 or greater on positron emission tomography is a powerful predictor of long-term mortality in patients with lymph node-negative pure and mixed bronchioloalveolar carcinoma who undergo complete surgical resection. Patients with a high level of FDG uptake (standardized uptake value > or = 2.5) may benefit from adjuvant chemotherapy or more frequent clinical follow-up.

Prognostic significance of clinical factors and Akt activation in patients with bronchioloalveolar carcinoma

PURPOSE

Lung cancer is the leading cause of cancer related mortality in the world. Bronchioloalveolar carcinoma (BAC) is a subset of NSCLC that has recently gained attention because of distinct biological and clinical features, increased incidence, and enhanced responsiveness to new therapies such as epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). However, prognostic features for BAC have not been well defined. Because activation of Akt is highly prevalent and a poor prognostic factor for other types of NSCLC, we assessed the prognostic significance of clinical features and Akt activation in patients with BAC.

METHODS

Forty-six cases of BAC in Iceland were classified according to WHO 1999 criteria. Akt activation was assessed using two phospho-specific antibodies against Akt (S473 and T308) in immunohistochemical (IHC) analysis. Associations between ordered Akt levels and other dichotomous parameters were evaluated using an exact Cochran-Armitage test for trend. Survival was analyzed by the Kaplan-Meier method and log-rank test, with hazard ratios (HR) determined by Cox proportional hazard models. The Cox model was also used to assess the joint effect of multiple factors on survival when they are considered simultaneously.

RESULTS

Age and histology (mucinous versus non-mucinous) were not associated with survival. Activation of Akt was highly prevalent in BAC, with only 2 out of 46 patients exhibiting negative staining with either antibody. Moderate to high Akt activation was observed in 63% of cases and was associated with non-mucinous histology. Akt activation was not associated with differences in survival or smoking status. In contrast, Cox model analysis revealed that male gender (HR 2.24, 95% CI, 1.07-4.71, p=0.032), advanced stage (III or IV) (HR 2.17, 95% CI, 1.004-4.71, p=0.049) and smoking status (HR 6.89, 95% CI, 1.49-31.88, p=0.013) were associated with a worse prognosis.

CONCLUSIONS

Male gender, advanced stage, and especially smoking status (but not Akt activation) are potentially important prognostic features for BAC. These features should be considered in the design and interpretation of clinical trials that enroll BAC patients.

Predictive factors for local recurrence of resected colorectal lung metastases

BACKGROUND

Wedge resection or segmentectomy are the preferred treatments for pulmonary metastasis from colorectal cancer. However, local recurrence at the surgical margin is a problem with limited resections. This study attempted to identify predictive factors associated with local recurrences at the surgical margin after resection of pulmonary metastases.

METHODS

A total of 96 lesions in 61 patients who had undergone a pulmonary wedge resection or segmentectomy for the treatment of pulmonary metastasis from colorectal cancer were investigated. Various clinical and pathologic factors were reviewed, and the risk of a local recurrence at the surgical margin was investigated.

RESULTS

After pulmonary resection, 34 of the 61 patients (56%) experienced recurrences in their lungs. Local recurrences at the surgical margin were found in 17 patients (28%), even though 15 of these 17 cases had been histologically confirmed as completely resected cases. No clinical factors associated with local recurrence at the surgical margin were identified. Pathologically, lesions exhibiting 10 or more aerogenous spreads with floating cancer cell clusters around the main tumor (p = 0.02) and a malignant positive surgical margin (p = 0.04) had a significantly higher risk of local recurrence.

CONCLUSIONS

The present study indicated that local recurrence may occur even in cases with a pathologically negative surgical margin. In cases with pulmonary metastases from colorectal cancer, lesions with 10 or more aerogenous spreads with floating cancer cell clusters around the main lesion and a malignant positive surgical margin in the resected specimens have a significantly higher risk of local recurrence at the surgical margin than those without.

[Bronchioloalveolar carcinoma in Spain: a rare and different form of lung cancer]

OBJECTIVE

To describe a series of cases of bronchioloalveolar carcinoma (BAC) treated surgically between 1993 and 1997 in the 19 hospitals that make up the Bronchogenic Carcinoma Cooperative Group of the Spanish Society of Pulmonology and Thoracic Surgery (GCCB-S).

PATIENTS AND METHODS

From a total of 2,944 cases of non-small cell lung cancer (NSCLC), 82 (3%) were BAC. The clinical characteristics and prognosis of patients with BAC were compared with those of the remaining 2,862 patients with NSCLC.

RESULTS

The percentage of men was lower for BAC than for other types of NSCLC (64.6% compared with 93.5%; P< .001) and BAC was associated with less comorbidity (50% vs 62%; P< .05), particularly in terms of chronic obstructive pulmonary disease (33% vs 47.2%; P< .05). Other characteristics showing significant differences were the higher frequency of BAC as a chance finding and the lower likelihood of weight loss or reduced performance status at the time of diagnosis. Classification as stage cI was significantly more common in patients with BAC (87% vs 75%; P.001), and this difference between groups was more pronounced for stage pI (68.5% vs 47%; P< .01). Only taking into account patients classified as stage pI with complete resection of NSCLC and following exclusion of operative mortality, patients with BAC presented an overall 5-year survival of 65% (95% confidence interval [CI], 51%-79%), compared with a significantly lower survival of 53% (95% CI, 50%-56%; P< .05) in patients with other forms of NSCLC.

CONCLUSIONS

In Spain, among cases of lung cancer treated by surgery, BAC is very rare (3%) and displays clinical characteristics that are different from other forms of NSCLC. Controlling for the most basic prognostic factors (stage pI and complete resection), survival is significantly higher for BAC.

Bronchioloalveolar carcinoma: a review

Bronchioloalveolar carcinoma (BAC) is classified as a subset of lung adenocarcinoma but has a distinct clinical presentation, tumor biology, response to therapy, and prognosis compared with other subtypes of non-small-cell lung carcinoma (NSCLC). Bronchioloalveolar carcinoma disproportionately affects women, never-smokers, and Asians and is characterized by growth along alveolar septae without evidence of stromal, vascular, or pleural invasion. Although pure BAC accounts for approximately 4% of lung cancers, tumors with histologically mixed BAC and adenocarcinoma account for > 20% of all NSCLCs, and the incidence of BAC might be increasing. Bronchioloalveolar carcinoma histology is most commonly found in small lesions identified incidentally on chest radiographs or computed tomography scans and might represent a precursor lesion to invasive adenocarcinoma. As with other subsets of NSCLC, surgical resection is the only potentially curative treatment. Patients with unresectable BAC are more likely to respond to the epidermal growth factor receptor tyrosine kinase inhibitors gefitinib and erlotinib than patients with other subtypes of NSCLC. Stage for stage, patients with BAC have a higher rate of long-term survival but might have an increased rate of intrathoracic recurrence than patients with other subtypes of NSCLC.

Redefining Bronchioloalveolar Carcinoma

Bronchioloalveolar carcinoma (BAC) is a subtype of non-small cell lung cancer (NSCLC) with distinct clinical and pathologic features. Although BAC appears to be on a pathologic continuum with adenocarcinoma, the most recent World Health Organization (WHO) classification system has set stringent criteria for the diagnosis. Though malignant, these cancers tend to be peripheral and grow in a lepedic fashion along the alveolar septae without parenchymal invasion. This clear distinction based on histopathology allows for a more definite separation of the natural history and behavior of BAC in clinical studies. Recent clinical trials of molecular targeted anticancer therapies have led to a deeper understanding of the unique features of this cancer and suggest that BAC may require a different therapeutic paradigm from other NSCLCs.

Bronchioloalveolar carcinoma of the lung 3 centimeters or less in diameter: a prognostic assessment

BACKGROUND

Bronchioloalveolar carcinoma (BAC) of the lung is a subtype of adenocarcinoma for which the incidence is actually rising, but the histologic definition of BAC has been recently changed by the revised World Health Organization (WHO) classification in 1999. The clinical features of patients with BAC diagnosed according to the recently revised WHO classification have not yet been clarified. In this retrospective study, we investigated the pattern of recurrence and survival outcome for patients with resected BAC by pathology review, compared with those in patients who had adenocarcinoma other than BAC.

METHODS

From 1985 through 2002, 108 patients underwent surgical resection for pulmonary adenocarcinoma 3 cm or less in diameter at the University of Yamanashi, Japan. All of the resected specimens of these 108 patients were pathologically reviewed again to confirm the diagnosis as BAC or adenocarcinoma other than BAC. The tumor was defined as BAC when the adenocarcinoma lesion had a pure bronchioloalveolar growth pattern and no evidence of stromal, vascular, or pleural invasion according to the WHO classification (third edition).

RESULTS

Twenty-five patients (23%) had a diagnosis of BAC, and 83 (77%) had a diagnosis of other adenocarcinoma. There was a female predominance among both patients with BAC and those with other adenocarcinoma. Lymph node involvement was seen for 30 lesions (36%) of adenocarcinoma other than BAC, but not for any BAC lesions. The median duration of follow-up after surgery was 5.1 years. There was no recurrence in the postoperative course in patients with BAC for a 5-year disease-free survival rate of 100%, whereas the 5-year disease-free survival rate for other adenocarcinoma was 63.5%.

CONCLUSIONS

The patients with resected BAC, which is defined as a noninvasive adenocarcinoma by the revised WHO classification, had an excellent prognosis. However, these results may depend on a strictly accurate pathology diagnosis as BAC. Limited resection might be curative in patients with focal BAC based on evidence of pathologic noninvasive features.

[Progressive upper lobe consolidation in a 73-year old healthy woman]

A 73-year old healthy woman presented for pacemaker replacement. Chest X-ray showed an right upper lobe consolidation. CT-scan and bronchoscopy with bronchoalveolar lavage could not yield a specific diagnosis. Due to progression of the consolidation in a CT scan after 10 weeks another bronchoscopy with transbronchial biopsy was performed and yielded bronchiolo-alveolar carcinoma. The patient underwent resection of the right upper lobe and middle lobe with curative intent.

Bronchoalveolar Carcinoma: Current Treatment and Future Trends

Bronchoalveolar carcinoma (BAC) is a subtype of non-small-cell lung cancer (NSCLC) with unique clinical and pathologic characteristics. The most recent classification system defines BAC as a primary lung cancer that tends to be peripheral and grow in a lepedic fashion along the alveolar septae without parenchymal invasion. Most of the clinical information on BAC comes from retrospective institutional reviews; however, recent studies have focused more specifically on BAC. In particular, clinical trials of molecular-targeted anticancer therapies against the epidermal growth factor receptor have led to a deeper understanding of the distinct features of this cancer and suggest that BAC may require a therapeutic paradigm different from that of other NSCLCs.

Grade of Stromal Invasion in Small Adenocarcinoma of the Lung

The pathologic features of invasion such as stromal disruption and pleural/vascular involvement have been shown to be of prognostic value in adenocarcinoma. However, the relationship between the degree of invasion, histologic subtype of adenocarcinoma, and prognosis remains unclear. We retrospectively studied 380 peripheral adenocarcinomas of < or = 2.0 cm in diameter with regard to histology and clinical profiles. Their degree of invasive growth was classified into four grades as follows according to the structural deformity and its location in the adenocarcinoma lesion: Grade 0 had a pure bronchioloalveolar growth pattern and no evidence of stromal invasion. Grade 1 had stromal invasion in the area of bronchioloalveolar growth. Grade 2 had stromal invasion localized on the periphery of a fibrotic focus. Grade 3 had stromal invasion into the center of a fibrotic focus. The clinicopathological data were obtained from medical records. The distribution of the histologic grade of invasion was as follows: grade 0 in 85 tumors (22%), grade 1 in 37 (10%), grade 2 in 46 (12%), and grade 3 in 212 (56%). This histologic grade of invasion was closely related to other indicators of tumor spread. Vascular/lymphatic permeation was seen in none of grade 0, in 1 lesion each of grade 1 and grade 2, and 144 (68%) of grade 3. Lymph node metastasis was seen in 57 (27%) lesions of grade 3 but not in grades 0, 1, or 2. The 5-year disease-free survival rates were 100%, 100%, 100%, and 59.6% for tumors with grade 0, grade 1, grade 2, and grade 3 invasion, respectively. Tumors with grade 1 and grade 2 invasion, like tumors with grade 0 invasion (bronchioloalveolar carcinoma), showed an excellent prognosis. Therefore, tumors with grade 1 and grade 2 invasion could be considered "minimally invasive" or "early" adenocarcinomas.

A novel technique for light delivery through branched or bent anatomic structures

OBJECTIVE

Photodynamic therapy is an effective cancer treatment, but light delivery constraints currently limit its application to superficial, easily visualized tumors. The goal of this study was to determine whether it would be possible to manipulate the optical properties of irregularly shaped anatomic structures for the purpose of light delivery. Such a technique could potentially expand the role of photodynamic therapy to treat tumors currently viewed as inaccessible to visible light.

METHODS

Ex vivo sheep tracheas and lungs were filled with substances of varying refractive indices. The effects on transmission of visible light of a known wavelength introduced into the proximal lumen of the organs were studied. Data were collected with naked-eye observation, standard photography, charge-coupled device imaging, and direct light measurement.

RESULTS

Filling a lung or trachea with a liquid possessing a refractive index higher than that of tissue dramatically increases the ability to deliver light around bends and through a branched network.

CONCLUSION

It is possible to manipulate the optical properties of an ex vivo organ for the purpose of enhanced light delivery.

Resection of multifocal non–small cell lung cancer when the bronchioloalveolar subtype is involved

OBJECTIVE

Bronchioloalveolar lung cancer is commonly multifocal and can also present with other non-small cell types. The staging and treatment of multifocal non-small cell cancer are controversial. We evaluated the current staging of multifocal bronchioloalveolar carcinoma and the therapeutic effectiveness of resection when this tumor type is involved.

METHODS

We reviewed our experience between 1992 and 2000 with complete pulmonary resections for bronchioloalveolar carcinoma. Kaplan-Meier survival curves were calculated from the dates of pulmonary resection.

RESULTS

Among 73 patients with bronchioloalveolar carcinoma, 14 patients, 7 male and 7 female with a mean age of 65 years (51-87 years), had multifocal lesions without lymph node metastases. Follow-up was 100% for a median of 5 years (range 2.6-8.5 years). Tumor distribution was unilateral in 9 patients and bilateral in 5 patients. The multifocal nature of the disease was discovered intraoperatively in 4 patients. Nine patients had 2 lesions, 4 patients had 3 lesions, and 1 patient had innumerable discrete foci in a single lobe. Operative mortality was 0. Postoperatively, 10 patients were staged pIIIB or pIV on the basis of multiple foci of similar morphology; 4 patients had some differences in histology (implying multiple stage 1 primaries). The median survival time to death from cancer was 14 months (141 days-5.6 years). The overall 5-year survival after resection of multifocal bronchioloalveolar carcinoma was 64%. Unilateral or bilateral distribution had no impact on survival.

CONCLUSIONS

The current staging system is not prognostic for multifocal bronchioloalveolar carcinoma without lymph node metastases. Complete resection of multifocal non-small cell lung cancer when bronchioloalveolar carcinoma is a component may achieve survivals similar to that of stage I and II unifocal non-small cell lung cancer. When bronchioloalveolar carcinoma is believed to be one of the cell types in multifocal disease without lymph node metastases, consideration should be given to surgical resection.

Reclassification of cystic bronchioloalveolar carcinomas to adenocarcinomas based on the revised World Health Organization Classification of Lung and Pleural Tumours

The objective of this study was to evaluate the radiologic-pathologic correlation of cystic change in cases of bronchioloalveolar carcinoma (BAC) using the 1999 revised World Health Organization Classification of Lung and Pleural Tumours. A total of 304 cases diagnosed as BAC before 1999 were reviewed retrospectively for radiologic findings of cystic change (n = 31). Of these, 20 had adequate clinical, pathologic, and radiologic material available for review. Patient demographics and history; the method, location, and size of specimen biopsy; and pathology reports were evaluated. A pulmonary pathologist reviewed the microscopic findings to confirm the diagnosis based on the 1999 World Health Organization criteria. Chest radiographs (n = 20) and computed tomographic scans (n = 11) were analyzed for location, size, and multiplicity of pulmonary nodules, masses, consolidations, or characterization of cystic change. Associated findings of lymphadenopathy, pleural effusion, atelectasis, and underlying lung disease were noted. There were 10 men and 10 women (mean age, 49.3 years) who participated in the study. Eleven were symptomatic. Pathologic review, based on the revised World Health Organization classification, yielded the diagnosis of adenocarcinoma (n = 14); adenocarcinoma, possible BAC (n = 4); and BAC (n = 2). Radiologically, adenocarcinoma (n = 14) manifested as a solitary pulmonary nodule/mass (n = 5) or consolidation (n = 6) and as multifocal mixed disease (n = 3) with solitary (n = 8) or multicystic (n = 6) change. Adenocarcinoma, possible BAC (n = 4) manifested as multifocal and multicystic consolidations (n = 2) or mixed disease (n = 1) and as a solitary cystic mass (n = 1). BAC (n = 2) manifested as a cystic mass (n = 1) and as multifocal multicystic mixed disease (n = 1). Most cases of BAC with radiologic cystic change were reclassified as adenocarcinoma. The radiologic features of BAC may need to be redefined in light of the current diagnostic criteria to help identify patients with limited and potentially curable disease.

Results of wedge resection for focal bronchioloalveolar carcinoma showing pure ground-glass attenuation on computed tomography

BACKGROUND

Focal bronchioloalveolar carcinoma (BAC) showing pure ground-glass attenuation (GGA) on thin-section computed tomography (CT), which is considered to be an early-stage adenocarcinoma, has been diagnosed with increasing frequency due to the development and spread of the helical CT scanner. We discussed the appropriateness of limited resection for this type of lesion.

METHODS

Between July 1996 and June 2001, 17 patients with localized BAC showing "pure GGA" (GGA without central scar formation) on thin-section CT underwent limited pulmonary resections. The mean patient age was 57.2 +/- 10.5 years old. Among these patients, four tumors were detected in a CT mass-screening program and the others were incidentally detected on CT during follow-up for other diseases. Fourteen patients underwent thoracoscopic wedge resection, and 3 underwent segmentectomy because of tumor location.

RESULTS

The mean tumor diameter was 7.9 +/- 1.9 mm. On pathological examination, all tumors showed a pure bronchioloalveolar growth pattern and no evidence of stromal, vascular, or pleural invasion. The median follow-up time was 32.0 months, with no cancer death or relapse to date.

CONCLUSIONS

Focal BAC showing pure GGA on thin-section CT is peripheral in situ adenocarcinoma. Wedge resection by VATS is considered to be an appropriate treatment for this type of lung cancer. It can be a minimally invasive complete resection for this type of early cancer, and offer the best chance for long-term survival and good quality of life.

DNA mismatch repair genes hMLH1, hMSH2, and hMSH6 are not inactivated in bronchioloalveolar carcinomas of the lung

BACKGROUND

Defective DNA mismatch repair (MMR) appears to be rare in nonsmall cell carcinomas of the lung. Defective DNA MMR results from genetic or epigenetic alterations that inactivate the DNA MMR genes hMLH1 or hMSH2, and rarely hMSH6. The loss of normal DNA MMR is thought to promote tumorigenesis by accelerating the accumulation of mutations in oncogenes and tumor suppressor genes. Inactivation of hMLH1, hMSH2, and hMSH6 is observed as a loss of expression of these proteins by immunohistochemistry. Bronchioloalveolar carcinoma is a subtype of adenocarcinoma with distinctive clinical and pathologic features.

MATERIALS AND METHODS

An immunohistochemical study was performed on paraffin embedded sections of 33 bronchioloalveolar carcinomas (20 nonmucinous and 13 mucinous) for hmlh1, hmsh2, and hmsh6 proteins. RESULTS All the tumors showed normal expression of hmlh1, hmsh2, and hmsh6.

CONCLUSIONS

These findings suggest that defective DNA MMR due to inactivation of hMLH1, hMSH2, or hMSH6 does not play a significant role in the pathogenesis of bronchioloalveolar carcinomas.

Bilateral bronchioloalveolar lung carcinoma: is there a place for palliative pneumonectomy?

OBJECTIVE

Bronchioloalveolar lung carcinoma (BAC) is characterized by bronchial and lymphatic dissemination explaining multifocal and bilateral spreading. Bilateral BAC is usually considered as a contraindication to surgery. Regarding poor efficacy of symptomatic and oncological treatments, we hypothesized that surgery might play a role to palliate hypoxemia associated with serious intrapulmonary shunting, as well as continuous bronchorrhea.

METHODS

We retrospectively studied here four consecutive patients, who underwent palliative pneumonectomy.

RESULTS

The shunt was confirmed again at the time of the surgery by a pulmonary artery occlusion demonstrating immediate improvement in arterial oxygen saturation from 89% at baseline to 98% after occlusion. Lung resections consisted of a left pneumonectomy in three cases and a right pneumonectomy in one. PaO(2) levels under 5l/min oxygen therapy improved dramatically when comparing preoperative data (mean 50.5 mmHg) to post-operative results (mean 150 mmHg). One patient died postoperatively. Three patients, who experienced an uneventful immediate post-operative course, received chemotherapy after surgery. Improvement of quality of life is testified by the absence of both symptoms and any need for oxygen therapy for few months. Disabling symptoms reappeared at 1, 8 and 10 months. Survival of these patients was 3, 12 and 18 months.

CONCLUSIONS

These results support the interest of consideration of a surgical resection for highly selected patients presenting with bilateral BAC and severe intrapulmonary shunting.