Atypical carcinoid of the lung. A distinct clinicopathologic entity

Well-Differentiated Neuroendocrine Carcinoma of the Lung: A Case Report

Well-differentiated neuroendocrine carcinoma (WDNC) of the lower respiratory tract displays clinical and radiologic features intermediate between carcinoids and small cell carcinoma and shares some biologic characteristics with both. We describe a case of WDNC resistant to three different treatments. The patient, a 42-year-old woman, received 2 cycles of chemotherapy before coming to our observation, including cyclophosphamide, adriamycin and vincristine, with progression of disease. We administered r-alpha-2a interferon for 2 months, but the patient showed clinical progression. Therefore, streptozotocln associated with epirubicin was utilized, but the patient died of disease progression after 4 cycles and 10 months from the first treatment. The case of WDNC described in this report showed an unusual aggressive clinical course and was refractory to conventional and unconventional treatments. The proper management for WDNC is still unknown. However, according to literature data, the chemotherapeutic schemes employed for small cell lung cancer represent the first treatment choice for WDNC. Further studies are needed to help define treatment strategies according to the biology of the tumor.

Primary Pulmonary Carcinoid Tumor: A Long-term Single Institution Experience

OBJECTIVES

Primary carcinoid tumors of the lung are rare tumors which comprise approximately 0.5% to 5% of all lung malignancies in adults and roughly 20% to 30% of all carcinoid tumors. The purpose of this retrospective, descriptive study was to describe the incidence, characteristics, and outcomes of patients treated for primary pulmonary carcinoid tumor at a single institution.

MATERIALS AND METHODS

All patients with a diagnosis of primary pulmonary carcinoid tumor treated from 1989 to 2009 were reviewed. Data collected included demographics, pathology, tobacco use, clinical presentation, tumor location, tumor spread, treatment, and survival.

RESULTS

There were 59 cases of pulmonary carcinoid tumors: 47 typical (80%) and 12 atypical (20%). All but 4 patients underwent surgery, including 54 (92%) lung-sparing resections and 1 pneumonectomy. Five of 55 patients received concurrent adjuvant chemoradiation therapy; 4 patients with atypical and 1 with typical histology. Three additional patients with atypical carcinoid were treated only with adjuvant radiotherapy, palliative radiotherapy, or palliative chemotherapy, respectively. The Kaplan-Meier 5- and 10-year overall survivals were both 80% within the entire population. In the 88% of patients who achieved complete remission, disease-free survival was 98%. A review of a large series from the literature is also presented.

CONCLUSIONS

Surgical resection was primary and adequate therapy for most typical carcinoid tumors with high overall survival and disease-free survival. Adjuvant chemotherapy or radiotherapy might be considered for patients with atypical carcinoid tumors who present with adverse pathologic findings.

Nothing But NET: A Review of Neuroendocrine Tumors and Carcinomas

This review covers the diverse topic of neuroendocrine neoplasms (NENs), a relatively rare and heterogeneous tumor type, comprising ~2% of all malignancies, with a prevalence of <200,000 in the United States, which makes it an orphan disease (Basu et al., 2010).1 For functional purposes, NENs are divided into two groups on the basis of clinical behavior, histology, and proliferation rate: well differentiated (low grade to intermediate grade) neuroendocrine tumors and poorly differentiated (high grade) neuroendocrine carcinoma (Bosman et al., 2010)2; this histological categorization/dichotomization is highly clinically relevant with respect to impact on treatment and prognosis even though it is not absolute since a subset of tumors with a low-grade appearance behaves similarly to high-grade lesions. Given the relative dearth of evidenced-based literature about this orphan disease as a whole (Modlin et al., 2008),3 since the focus of most articles is on particular anatomic subtypes of NENs (i.e., gastroenteropancreatic or pulmonary), the purpose of this review is to summarize the presentation, pathophysiology, staging, current standard of care treatments, and active areas of current research.

Multimodality Imaging Findings in Carcinoid Tumors: A Head-to-Toe Spectrum

Carcinoid tumors are a rare biologically heterogeneous group of neuroendocrine tumors with a spectrum ranging from benign indolent to aggressive metastatic tumors. They belong to the category of amine precursor uptake and decarboxylase tumors, or apudomas. The most common sites for primary locations are the gastrointestinal and respiratory tracts; however, any organ can be involved. The clinical presentation depends on location, aggressiveness, production of biologically active amines and peptides, paraneoplastic syndromes, and tendency for metastasis. Their reported age-adjusted incidence has increased in recent years, partly due to improved detection at radiologic imaging and endoscopy. Not a ll neuroendocrine cell tumors are carcinoids. Numerous systems have been proposed regarding their nomenclature and classification. Cross-sectional and functional imaging plays an important role in diagnosis, lesion characterization, and staging. Awareness of nomenclature, classification, common sites of involvement, and imaging presentation are pivotal for making the diagnosis. Knowledge of the diverse clinical, pathologic, and radiologic spectrum of carcinoid tumors involving various organs of the body is important for diagnosis and patient management. ^©RSNA, 2017.

Neuroendocrine tumors: beyond the abdomen

Several classification systems for neuroendocrine tumors (NETs) exist, which use variable terminology and criteria for grading and staging. This variability in terminology can cause confusion and difficulty in recognizing which tumors are, in fact, members of this heterogeneous group of malignancies. The largest group of NETs, the gastroenteropancreatic NETs, has been well described and characterized; however, there are less-recognized extra-abdominal NETs that can arise from nearly any organ in the body. In this article, the clinical features and imaging appearances of the extra-abdominal NETs will be reviewed, compared, and contrasted. This diverse group consists of paragangliomas, Merkel cell carcinomas, esthesioneuroblastomas, NETs of the lung, and medullary thyroid carcinomas. Recognition of these tumors as part of the larger group of NETs is important for understanding how best to approach imaging for their diagnosis, staging, and potential treatment. Familiarity with the computed tomographic and magnetic resonance imaging appearances and the role of radionuclide imaging of these heterogeneous groups aids in the correct diagnosis and in treatment planning.

Alterations in the expression of p53, KLF4, and p21 in neuroendocrine lung tumors

CONTEXT

Neuroendocrine lung neoplasms are a heterogeneous group of tumors with different clinical behavior and prognosis.

OBJECTIVES

To evaluate the expression of p53, KLF4, and p21 in neuroendocrine lung neoplasms and to analyze the influence that expression has on the prognosis of those tumors.

DESIGN

All neuroendocrine lung neoplasms (N = 109) resected in our institution were reviewed, with the collection of histologic slides and paraffin blocks of 47 typical carcinoids (43%), 9 atypical carcinoids (8%), 35 large cell neuroendocrine carcinomas (32%), and 18 small cell lung carcinomas (17%), as well as 10 tumorlets (100%). Four tissue microarrays were performed. Follow-up was assessed in all cases (119 of 119; 100%).

RESULTS

p53 protein immunostaining results were negative in both the tumorlets and typical carcinoids and were overexpressed in 11% (1 of 9) of the atypical carcinoids and in 68% (36 of 53) of the carcinomas. KLF4 results were positive in all tumorlets (10 of 10; 100%), 32% (15 of 47) of the typical carcinoids, 44% (4 of 9) of the atypical carcinoids, and 62% (33 of 53) of the carcinomas. p21 expression did not differ among the groups. The lack of KLF4 and p21 expression was associated with an accumulation of aggressive features in typical carcinoids (P = .04 and P = .004, respectively, Fisher exact test).

CONCLUSIONS

p53, KLF4, and p21 showed altered expression patterns in pulmonary neuroendocrine neoplasms. Lack of KLF4 and p21 expression was associated with accumulation of aggressive features in typical carcinoids.

A case of typical pulmonary carcinoid tumor treated with bronchoscopic therapy followed by lobectomy

Carcinoid bronchopulmonary tumors represent approximately 25% of all carcinoid tumors and 1%-2% of all lung neoplasms. The most common symptoms are: persistent cough, asthma-like wheezing, chest pain, dyspnea, hemoptysis and obstructive pneumonitis. We present a case of a young adult diagnosed with a typical carcinoid tumor. The diagnosis was established on the basis of imaging examination and bronchoscopic biopsy. The patient was treated with bronchoscopic electrocautery therapy to relieve the obstructed airway, followed by surgical lobectomy in order to entirely remove the exophytic damage. This approach was not only a palliative management to bronchial obstruction but also avoided pneumonectomy. Recent studies support the use of such interventional resection methods, as they may result in a more conservative surgical resection.

[Multidetector computed tomography assessment of the degree of differentiation of bronchial carcinoid tumors]

OBJECTIVE

To define the CT findings for bronchial carcinoid tumors and to determine whether these findings enable these tumors to be classified as typical or atypical.

MATERIAL AND METHODS

We reviewed the chest CT studies performed between 1 January 2001 and 31 December 2009 in patients at our hospital diagnosed with bronchial carcinoid tumors. The sample consisted of 52 patients (23 women and 29 men) with a mean age of 47 years (range 11-77 years). The 52 cases were classified as typical or atypical on the basis of the following radiological findings: size, location, focality, type of growth, calcifications, signs secondary to bronchial obstruction, and the presence of significant lymph node enlargement or metastases. These findings were then compared with the histological findings.

RESULTS

Typical carcinoid tumors were the most prevalent (46 cases). The variables associated with atypical tumors were: male sex, advanced age at onset, and size >3cm. The accuracy of CT in classifying atypical tumors correctly increased with the number of variables indicative of atypical carcinoid tumors. A negative result for atypical nature made it possible to rule out an atypical carcinoid tumor in 95% of the cases.

CONCLUSION

CT is useful for defining and characterizing carcinoid tumors into typical or atypical, although a precise formula for differentiating between the two types remains to be defined.

Pulmonary neuroendocrine neoplasms: a review of clinicopathologic and cytologic features

Neuroendocrine tumors form a distinct group of lung neoplasms sharing characteristic cytohistologic, immunohistochemical, ultrastructural, and molecular features. The objective of this review article is to discuss the diagnostic classifications and the morphologic cytologic-histologic features for the different categories of neuroendocrine tumors of the lung. An accurate characterization of the neuroendocrine tumors of the lung requires knowledge of specific criteria separating the major categories, which is highly essential for determining prognosis and treatment options for these patients.

Ten-year adjuvant treatment with somatostatin analogs in a patient with atypical carcinoid of the lung

Both typical carcinoid and atypical carcinoid (AC) of the lung are surgically curable, but AC carries a considerably worse prognosis because of a relatively high rate of recurrence. Adjuvant therapy can be conducted with radiotherapy, chemotherapy, and somatostatin analogs (SST-As), but its effectiveness in preventing locoregional and distant recurrences is yet to be fully investigated. A 48-year-old woman, presenting with AC, was free of both radiographical and biochemical signs of residual disease, after surgery and chemotherapy. To prevent disease recurrence, she underwent long-term adjuvant treatment based on SST-As. During the 10-year follow-up period, no side effects referable to SST-As have been reported and no evidence of recurrence of the disease has been detected. In consideration of the relatively high recurrence rate of the disease and of excellent tolerance for SST-As, long-term adjuvant treatment based on SST-As could become a therapeutic option for surgically cured patients with AC. Clinical investigations, conducted in large samples of patients, are necessary to evaluate the effectiveness of such an approach.

Neuroendocrine carcinomas of the lung: a critical analysis

Neuroendocrine carcinomas represent an important group of primary neoplasms in the lung. During the last decades, the nomenclature of these tumors has evolved and the current use of immunohistochemical and molecular biology studies have, to some extent, expanded the conventional view of these tumors. However, the primary diagnosis of most of these lesions is performed on limited biopsy specimens, which may not translate well when one is confronted with a nomenclature that is based on resected material. In addition, for some of these specific entities, some confusion and controversy apparently remain, allowing for the proliferations of different terms that, although they may be dismissed as "semantics," may have a role in interpretation, further subclassification, and, possibly, treatment. Herein we review current concepts regarding the classification of these neoplasms and the role of this classification in our daily practice and discuss how it may impact treatment.

[Clinico-radiological characteristics of bronchial carcinoid]

OBJECTIVES

To review clinical and radiological characteristics of a patients with bronchial carcinoid.

METHODS

In this retrospective study, we reviewed the clinical, pathological and imaging findings in 42 patients diagnosed with bronchial carcinoid during the seven years period.

RESULTS

There were 23 women and 19 men, with a mean age of 47 years (range from 15 to 75). Thirty patients had typical and 12 atypical bronchial carcinoid. Dominant symtoms were cough (46.7%) and 38%. Tumor was localized in 28 patients in the left, and 14 in the right lung. On radiographs carcinoid manifested as tumor shadow in 40.5%, nodule and atelectasis in 21.4% cases each respectively, pleural effusion and pneumonia in 7.1% each respectively and hyperinflation in 2.4% of the cases. Computerized tomography revealed endoluminal tumor in 30.9% patients.

CONCLUSION

Major imaging findings are central, tumor mass or nodule and obstruction signs like atelectasis. Diagnosis is confirmed by pathological examination of samples taken by bronchoscopy or surgery.

Neuroendocrine carcinomas (carcinoid, atypical carcinoid, small cell carcinoma, and large cell neuroendocrine carcinoma): current concepts

Neuroendocrine carcinomas are ubiquitous neoplasms that may occur anywhere in the human body. A unifying concept regarding the classification of these tumors has been controversial. Although most neuroendocrine neoplasms occur in the gastrointestinal tract, current concepts regarding classification and nomenclature are being driven by studies of thoracic tumors. One issue that has been put forward to keep separate nomenclatures for these tumors in different organ systems is the different clinical behavior of these neoplasms in different systems. The most important aspect regarding this group of tumors is the fact that they should be considered neoplasms capable of local recurrence and distant metastasis. Close clinical correlation and appropriate treatment are important to improve the survival rate in this group of patients.

Neuroendocrine tumors of the lung: clinical, pathologic, and imaging findings

Neuroendocrine tumors of the lung arise from Kulchitzky cells of the bronchial mucosa and comprise typical carcinoid, atypical carcinoid, large cell neuroendocrine carcinoma (LCNEC), and small cell lung cancer (SCLC). At histopathologic analysis, these tumors demonstrate a progressive increase in the number of mitotic figures per 10 high-power fields of viable tumor and in the extent of necrosis, with typical carcinoid having the lowest values and SCLC having the highest. Typical carcinoid is less aggressive than atypical carcinoid, although these tumors have similar gross pathologic and radiologic features; LCNEC has a prognosis between that of atypical carcinoid and that of SCLC. SCLC is the most aggressive pulmonary neuroendocrine tumor and has the most specific imaging feature: mediastinal or hilar lymphadenopathy. At CT, carcinoid tumors appear as a spherical or ovoid nodule or mass with a well-defined and slightly lobulated border. When nonspherical, the tumor is elongated with its long axis parallel to adjacent bronchi. Calcification or ossification is seen in up to 30% of cases. The CT findings of LCNEC are nonspecific and are similar to those of other non-small cell lung cancers. Although there are some overlapping features between these tumors, integration of the clinical and imaging features may be helpful in differentiation of pulmonary neuroendocrine tumors.

Clinical-radiological presentation and outcome of surgically treated pulmonary carcinoid tumours: a long-term single institution experience

PURPOSE

To determine the presenting features and the outcome of surgically treated pulmonary carcinoid tumours.

METHODS

Retrospective analysis of all consecutive cases with preoperatively suspected or proven pulmonary carcinoid, treated between 1964 and 1994, in order to have full 5-year survival data.

RESULTS

Seventy-three patients were retrieved, six had a postoperative histology other than carcinoid. The mean age of the 67 eligible cases was 44 years (range 17-74). There were 59 typical and eight atypical carcinoids. The most frequent presenting symptom was infection, followed by haemoptysis. Sixteen patients were asymptomatic, 15 of these had an abnormal chest X-ray, showing a solitary nodule in 13. Bronchoscopy was abnormal in almost all symptomatic patients. Bronchial biopsy results suggested a malignancy other than carcinoid in seven of eight patients whose postoperative histology was found to be atypical carcinoid. There were 40 lobectomies, 14 bi-lobectomies, nine pneumonectomies, and four limited resections. Ten patients had lymph node involvement (seven typical and three atypical). There was no correlation between the diameter of the primary tumour and the presence of nodal involvement. In particular, three of eight peripheral lesions <30 mm were found to have metastatic lymph nodes. The 5-year survival was 92% (95% in N0 versus 56% in N1-2; 92% in typical versus 67% in atypical). The 10-year survival was 84%.

CONCLUSION

The specific diagnosis of atypical carcinoid cannot be reliably made on bronchial biopsies. No relationship was found between tumour size and the presence of lymph node metastases, suggesting that radical excision with detailed lymph node sampling is as important in carcinoids as in other lung cancers. Long-term survival was excellent, nodal status and pathology (typical/atypical) were independent prognostic factors.

Update in pulmonary carcinoid tumors: a review article

Pulmonary carcinoid tumors are neuroendocrine malignant tumors that make up 1% to 2% of all lung tumors. According to histopathologic criteria, carcinoids can be divided into typical (TC) and atypical (AC) carcinoids. Carcinoids can be placed in a spectrum of neuroendocrine tumors, ranging from low-grade malignant TC to intermediate AC to high-grade large-cell neuroendocrine carcinoma and small-cell lung carcinoma. Familial pulmonary carcinoids are rare. The most common symptoms are hemoptysis, cough, recurrent pulmonary infection, fever, chest discomfort and chest pain, unilateral wheezing, and shortness of breath. Paraneoplastic syndromes are rare and include carcinoid syndrome, Cushing's syndrome, and ectopic growth hormone-releasing hormone secretion. The diagnosis is usually established by flexible bronchoscopy and biopsy, although occasionally this can result in severe hemorrhage. Immunoscintigraphy by somatostatin analogs can also be useful in diagnosis. The treatment of choice is surgical resection, and prognosis is relatively good in TC, although it is worse in AC. The role of radiotherapy and chemotherapy as part of multimodality treatment or palliation is still debated.

The role of radiation therapy and chemotherapy in the management of airway tumors other than small-cell carcinoma and non-small-cell carcinoma

In rare pulmonary tumors, the choice of local and systemic therapy is frequently dictated by the histologic cell type and (generally) by extrapolation from the existing therapeutic literature for that cell type's more common presentation; however, this approach might change. We are in the midst of a new biological and technological era in how approach and treat cancer. In a phase I trial for non-small-cell lung cancer, Hayman et al safely treated with radiation doses as high as 102.9 Gy (to limited volumes) using three-dimensional, conformal radiation [100]. Such techniques facilitate radiation dose escalation for thoracic neoplasms while minimizing normal tissue toxicity, potentially enhancing the therapeutic ratio. Furthermore, the entire human genome has been sequenced recently, and scientists are now in the process of discovering the functions of previously unknown sequences and their protein products. DNA microarrays can be used to analyze small tissue samples for the presence of gene variations or mutations (genotyping), performing the equivalent of several thousand "Southern blot" experiments in only a few days. In the future, patients might receive individually tailored therapy based upon unique molecular-genetic alterations of the tumor.

Outcomes and patterns of failure in bronchial carcinoid tumors

PURPOSE

To clarify the natural history, prognosis, and treatment failure patterns for bronchial carcinoid tumors according to their clinical and histopathologic features.

METHODS

The charts of 241 patients from our institution with bronchial carcinoid tumors were reviewed. Thirty-four patients had no follow-up, yielding a study population of 206. Of the 206 patients, 62 had atypical carcinoid (AC) and 144 had typical carcinoid (TC) tumors.

RESULTS

The 5-, 10-, and 20-year disease-specific survival rates were lower in patients with AC (60.1%, 36.8%, and 28.1%, respectively) than in those with TC (79.0%, 62.9%, and 38.8%, respectively; p = 0.0002). Predictors of poor outcome included more advanced stage (p <0.00001), male gender (p = 0.019), symptoms at presentation (p = 0.013), and age >or=60 years (p = 0.02). Stage I AC was associated with a median disease-free survival of 96 months compared with 222 months for Stage I TC (p = 0.0002) and had an actuarial 22% locoregional failure rate 5 years after surgery compared with 6% for Stage I TC (p = 0.022). The disease-free survival for Stage II and III AC was worse than that for Stage II or III TC, but the difference did not reach statistical significance (p = 0.15). Locoregional failure was also prominent in Stage II and III AC. Second malignancies were common in patients with bronchial carcinoids (56 of 206 patients).

CONCLUSION

Stage-for-stage, the outcome is worse for patients with AC than for those with TC. Locoregional failure is common after curative resection, even for early-stage AC. Second cancers are common in patients with carcinoid tumors.

Pulmonary neuroendocrine carcinomas. A review of 234 cases and a statistical analysis of 50 cases treated at one institution using a simple clinicopathologic classification

CONTEXT

Primary pulmonary neuroendocrine tumors are traditionally classified into 3 major types: typical carcinoid (TC), atypical carcinoid (AC), and large cell neuroendocrine carcinoma (LC) or small cell neuroendocrine carcinoma (SC). Confusion arises frequently regarding the malignant nature of TC and the morphologic differentiation between AC and LC or SC.

OBJECTIVE

To provide clinicopathologic evidence to streamline and clarify the histomorphologic criteria for this group of tumors, emphasizing the prognostic implications.

PATIENTS

To minimize variability in diagnostic criteria and treatment plans, we analyzed a group of patients whose diagnosis and treatment occurred at a single institution. We reviewed 234 cases of primary pulmonary neuroendocrine tumors and thoroughly studied 50 cases of resected tumors from 1986 to 1995.

RESULTS

On the basis of morphologic characteristics and biologic behaviors of the tumors, we agree with many previous investigators that these tumors are all malignant and potentially aggressive. Based on our accumulated data, we have modified Gould criteria and reclassified these tumors into 5 types: (1) well-differentiated neuroendocrine carcinoma (otherwise called TC) (14 cases, with less than 1 mitosis per 10 high-power fields [HPF] with or without minimal necrosis); (2) moderately differentiated neuroendocrine carcinoma (otherwise called low-grade AC) (6 cases, with less than 10 mitoses per 10 HPF and necrosis evident at high magnification); (3) poorly differentiated neuroendocrine carcinoma (otherwise called high-grade AC) (10 cases, with more than 10 mitoses per 10 HPF and necrosis evident at low-power magnification); (4) undifferentiated LC (5 cases, with more than 30 mitoses per 10 HPF and marked necrosis); and (5) undifferentiated SC (15 cases, with more than 30 mitoses per 10 HPF and marked necrosis). The 5-year survival rates were 93%, 83%, 70%, 60%, and 40% for well, moderately, and poorly differentiated, and undifferentiated large cell and small cell neuroendocrine carcinomas, respectively. We found nodal metastasis in 28% of TC in this retrospective review, a figure higher than previously recorded.

CONCLUSION

Using a grading system and terms comparable to those used for many years and used for neuroendocrine tumors elsewhere in the body, we found that classification of pulmonary neuroendocrine carcinomas as well, moderately, poorly differentiated, or undifferentiated provides prognostic information and avoids misleading terms and concepts. This facilitates communication between pathologists and clinicians and thereby improves diagnosis and management of the patient.

Bronchial carcinoid tumors of the thorax: spectrum of radiologic findings

Bronchial carcinoid tumors are neuroendocrine neoplasms that range from low-grade typical carcinoids to more aggressive atypical carcinoids and therefore demonstrate a wide spectrum of clinical behaviors and histologic features. Typical and atypical bronchial carcinoids have similar imaging features. Because most bronchial carcinoids are located in central airways, radiologic findings are usually related to bronchial obstruction. Central bronchial carcinoids manifest as an endobronchial nodule or hilar or perihilar mass with a close anatomic relationship to the bronchus. The mass is usually a well-defined, round or ovoid lesion and may be slightly lobulated at radiography and computed tomography (CT). Associated atelectasis, air trapping, obstructing pneumonitis, and mucoid impaction may also be seen. Peripheral bronchial carcinoids appear as solitary nodules. Calcification is common and is easily visualized at CT. Bronchial carcinoids demonstrate high signal intensity on T2-weighted and short-inversion-time inversion recovery magnetic resonance images. Prognosis of bronchial carcinoids is highly dependent on histologic findings: Atypical carcinoids have certain features that suggest a more aggressive nature. Typical bronchial carcinoids generally have an excellent prognosis, whereas atypical bronchial carcinoids have a worse prognosis. Therefore, understanding the histologic, clinical, and radiologic features of bronchial carcinoids facilitates accurate diagnosis and helps optimize surgical planning.

Diagnosis of high-grade pulmonary neuroendocrine carcinoma by fine-needle aspiration biopsy: nonsmall-cell or small-cell type?

A consensus optimal therapy for large-cell neuroendocrine carcinoma of the lung has not been achieved since this entity was proposed in 1991. Accumulation of clinical data and investigation, however, can be greatly impeded by erroneous cytological diagnosis, based on which treatment may be initiated. To avoid erroneous diagnoses, cytological criteria need to be defined. Twenty cases of fine-needle aspiration specimens with a diagnosis of neuroendocrine tumor by either cytology or follow-up histology were retrospectively reviewed for cytomorphologic features. Patients' clinical data were also reviewed. Three cytomorphologic patterns were identified for large-cell neuroendocrine carcinoma, i.e., nonsmall-cell-like, small-cell-like and, mixed nonsmall-cell-small-cell-like. Small-cell-like large-cell neuroendocrine carcinoma can be mistaken for small-cell carcinoma. The most important differential features between these two entities are nuclear size and perceptibility of nucleoli of tumor cells.

Unusual primary lung neoplasms

Bronchial carcinoids and hamartomas are, respectively, the most common malignant and benign unusual primary lung neoplasms. These tumors are often asymptomatic but can cause central airway obstruction. Helical computed tomographic and radionuclide scintigraphic advances in their detection and evolution, together with newer interventional bronchoscopy techniques such as neodymium:yttrium-aluminum-garnet laser phototherapy and cryotherapy, represent important improvements in the diagnosis and management of patients with such tumors.

Diagnostic and therapeutic management of neuroendocrine lung tumors: a clinical study of 44 cases

Neuroendocrine tumors of the lung (NTL) are a distinct subset of tumors with a wide range of histological patterns and clinical behavior. Controversy still exists as to the ideal diagnostic and therapeutic approach to these neoplasms. A series of 44 consecutive NTL patients operated on at our Institution was retrospectively reviewed in order to critically analyze the diagnostic and therapeutic management. A preoperative diagnosis was obtained in 11 patients (25%). All patients underwent an anatomical surgical resection with lymphoadenectomy. Pathological diagnosis was typical carcinoid (TC) tumor in 36 cases, atypical carcinoid (AC) in three and large-cell neuroendocrine carcinoma (LCNEC) in five. One patient had preoperative chemotherapy. Node-positive patients received postoperative radiotherapy on the mediastinal area. Median follow-up time was 40 months for TC and 51.5 months for AC/LCNEC. Recurrence of disease was observed in three patients with TC and in two with AC/LCNEC. Actuarial 5-year survival was 93% for TC and 70% for AC/LCNEC. Survival was not influenced by tumor size, while lymph node metastases were associated with a worse prognosis. However, due to the limited number of patients, no statistical significance was observed. In conclusion, our study confirms findings in the literature showing that TC and AC/LCNEC are clinically different, and that a differential preoperative diagnosis and treatment is necessary. Although the results of new diagnostic techniques such as octreotide scintigraphy are encouraging, they need to be validated in a larger number of patients. Surgery, with anatomical resection and lymphoadenectomy, remains the treatment of choice in all these tumors. Laser treatment should be considered only as a palliative procedure or as a complementary technique to surgery. The role of adjuvant treatments in AC and LCNEC is uncertain and should be evaluated in larger trials. The prognostic role of biological factors such as cytometry and genetic markers requires further investigation before any definitive conclusions can be drawn.

Prognostic factors in neuroendocrine lung tumors: a Spanish Multicenter Study. Spanish Multicenter Study of Neuroendocrine Tumors of the Lung of the Spanish Society of Pneumonology and Thoracic Surgery (EMETNE-SEPAR)

BACKGROUND

This study examines the experience of the Spanish Multicenter Study of Neuroendocrine Tumors of the Lung through the clinical data and behavior of patients treated for this pathologic process.

METHODS

From 1980 to 1997, 361 cases of neuroendocrine carcinomas (NEC) were treated surgically. Patients were enrolled in a protocol using the pathologic and follow-up reports. According to Dreslers' criteria, the cases were segregated into grade 1 (typical carcinoid), grade 2 (atypical carcinoid), grade 3 large cell type, and grade 3 small cell type. Several variables were reviewed in all patients. Statistical analysis was performed to determine whether clinical characteristics and differentiation were associated with significant differences in the prognosis.

RESULTS

A total of 261 cases of NEC were identified with grade 1, 43 with grade 2, and with grade 3: 22 of large and 35 of small cells. Five-year survival for different grades was as follows: grade 1, 96%; 2, 72%; 3 large cell type, 21%; and 3 small cell type, 14%. When a comparative analysis between typical and atypical carcinoids was performed a significant difference for mean age, tumor size, nodal metastases, and recurrence was observed. However, female sex, nodal metastases, and recurrence rate differed between atypical carcinoids and grade 3 NEC of large cells. A difference in recurrence rate was found between patients with both types of grade 3 NEC.

CONCLUSIONS

The progressive deterioration of tumor organization highlights that neuroendocrine tumors constitute a continuous spectrum. A careful observation of pathologic findings is necessary to individualize their prognostic factors.

Bronchial carcinoid tumor presenting with complete lobar collapse and unilateral lung emphysema

Bronchial carcinoid tumors have different radiographic manifestations. This is a presentation of a case of bronchial carcinoid tumor which presented with complete right upper lobe collapse and emphysematous change of the right residual lung. According to bronchoscopic and operative findings, the emphysematous change of the right residual lung was contributed by a check-valve effect of the endobronchial tumor of the right main bronchus and a compensatory effect of the right residual lung post complete collapse of the right upper lobe.

Thoracic carcinoids: radiologic-pathologic correlation

Carcinoids are neuroendocrine neoplasms. Bronchial carcinoids are unusual, malignant primary neoplasms that characteristically involve the central airways and typically exhibit well-defined margins and bronchial-related growth. Bronchial carcinoids include low-grade typical carcinoids and the more aggressive atypical carcinoids. These tumors usually affect patients in the 3rd through 7th decades of life who are often symptomatic with cough, hemoptysis, or obstructive pneumonia. Bronchial carcinoids radiologically manifest as hilar or perihilar masses, with or without associated atelectasis, pneumonia, bronchiectasis, or mucoid impaction. At computed tomography, an anatomic relationship of these tumors to a bronchus is usually seen, and they may show contrast material enhancement or calcification. In rare cases, carcinoids occur in the thymus; when they do, they are aggressive tumors that affect adults who usually present with chest pain, cough, and dyspnea. Thymic carcinoids manifest radiologically as anterior mediastinal masses and may mimic thymomas. Thoracic carcinoids are treated by surgical excision. The prognosis for patients with typical bronchial carcinoids is excellent; patients with atypical bronchial or thymic carcinoids have a worse prognosis.

Bronchial carcinoid tumours: a study on clinicopathological features and role of octreotide scintigraphy

Several authors proposed the stage at diagnosis and some histopathological features as prognostic factors of bronchial carcinoids. However, since large tumour diameters or nodal metastases are frequently associated to aggressive histology, their prognostic role is unclear. To investigate the relationships between the clinicopathological parameters at diagnosis and outcome, 21 patients were analysed. Overall 26% of the radically resected patients recurred. Recurrences and disease-specific mortality were related to atypical histology and, only in cases with typical histology, to the presence of hilar or mediastinal lymph node metastases. These prognostic factors were valuable independently of the size of the primary tumour, that was remarkably homogeneous, always less than 3 cm, thus not predictive of recurrence. Moreover we evaluated the role of somatostatin receptor scintigraphy, a diagnostic tool only preliminary studied in this field. Scintigraphy with 111In-octreotide revealed the primary tumours at diagnosis (8/8), the increase in tumour size in two unresected patients, and all the cases of recurrent or metastatic disease (5/11), sometimes before the appearance of symptoms. These results suggest the usefulness of histology and nodal status as prognostic factors in clinical practice. Somatostatin receptor scintigraphy turns out to be a powerful diagnostic tool, for an accurate staging and an early diagnosis of recurrence in bronchial carcinoids.

Apoptosis and expression of bcl-2 protein are inverse factors influencing tumour cell turnover in primary carcinoid tumours of the lung

AIMS

This study evaluates potential regulating factors in primary pulmonary carcinoid tumours, 16 typical and four atypical samples, with special emphasis on apoptosis and the bcl-2 gene family. Furthermore, p53-related oncogenes were analysed in a search for associated biological parameters.

METHODS AND RESULTS

The in-situ end-labelling technique (ISEL) was used to determine apoptotic cells, in addition to immunohistochemical methods, which were used to investigate the expression of the Ki67 antigen (avidinbiotin complex (ABC) method) and bcl-2, bcl-x, p53, p21/waf1, p27 and mdm-2 proteins (catalysed reporter deposition (CARD) technique). The incidence of apoptotic tumour cells was significantly enhanced in typical carcinoids. The bcl-2 protein was expressed to a higher degree in atypical carcinoids, which displayed a higher proliferative capacity as well. In contrast, bcl-x was observed predominantly in so-called typical carcinoids. The tumour cell turnover index was the most distinguishing parameter between both entities. All carcinoid tumours failed to show a staining for p53, p21/waf. p27 and mdm-2 proteins.

CONCLUSIONS

The different biological behaviour of the carcinoid tumours under study seems to be influenced by the bcl-2 gene family preventing programmed cell death. We speculate that this results in a more aggressive course in atypical carcinoid tumours.

Survival analysis of 200 pulmonary neuroendocrine tumors with clarification of criteria for atypical carcinoid and its separation from typical carcinoid

Neuroendocrine tumors of the lung embrace a spectrum from low-grade typical carcinoid (TC), intermediate-grade atypical carcinoid (AC), and high-grade categories of large cell neuroendocrine carcinoma (LCNEC) and small cell carcinoma (SCLC). We studied 200 neuroendocrine lung tumors to critically evaluate the Arrigoni histologic criteria for AC using statistical analysis to delimit more rigorously an intermediate survival for AC between TC and the high-grade tumors of LCNEC and SCLC. Histologic features that might predict prognosis were used for Kaplan-Meier and Cox proportional hazards survival analysis, and an optimal mitotic range for AC was calculated. The optimal mitotic range for AC was 2 to 10 mitoses per 2 mm2 of viable tumor (10 high-power fields). Based on this finding, we collapsed mitoses into three categories (< 2; 2-10; > or = 11) and performed Cox multivariate analysis for all 200 neuroendocrine tumors. Mitotic counts were the only independent predictor of prognosis. Based on this analysis, we propose that AC be defined as a tumor with neuroendocrine morphology, mitotic counts between 2-10 per 2 mm2 of viable tumor (10 high-power fields), or coagulative necrosis. Using these criteria, the 200 neuroendocrine tumors were classified as 51 TC, 62 AC, 37 LCNEC, and 50 SCLC. The 5- and 10-year survival was 87% and 87% for TC, 56% and 35% for AC, 27% and 9% for LCNEC, and 9% and 5% for SCLC, respectively. After stratification for stage, survival for AC was significantly worse than for TC (p < 0.001); for LCNEC and SCLC it was significantly worse than for AC; but the survival for LCNEC was no different than that for SCLC.

Carcinoid tumors of the lung and family history of cancer

Family history of cancer has been described among patients with lung neoplasms. Carcinoid tumors, originally thought to be slow growing and nonmetastatic, have not historically been included in these studies. In some instances these tumors have demonstrated aggressive metastatic potential. A medical record review of 86 patients with histopathologically confirmed carcinoid tumors of the lung, treated at the University of Texas M.D. Anderson Cancer Center between 1959 and 1994, was conducted to describe family history of cancer. Family history of cancer was recorded in 74 (86%) of the medical records and 32 (43%) reported first-degree relatives with cancer. Five-year survival for patients with affected relatives was 45% and 73% for patients without affected relatives (p = .23). Among 67 patients without metastatic disease at diagnosis, the risk of distant metastasis by 5 years was 40% among patients with a positive family history of cancer compared to 6% of the patients without affected relatives (p = .03), (rate ratio 5.01). These results suggest that genetic susceptibility may affect the metastatic potential of some carcinoid tumors.

DNA cytophotometry and prognosis in typical and atypical bronchopulmonary carcinoids. A clinicomorphologic study of 100 neuroendocrine lung tumors

Surgical material obtained from 100 patients with typical carcinoids (TC) and atypical carcinoids (AC) of the lung (including 100 primary, four residual tumors, and four lymph node or distant metastases) was investigated by conventional histology and scanning DNA cytophotometry. Of the 60 TC (96%), 58 exhibited euploid DNA histograms compared with only 20 (50%) of the 40 AC. The morphologic findings were related to the patients' survival (median observation period, 9 years). Statistical analyses disclosed the histologic type of disease (TC versus AC) and the DNA content of tumors (euploid versus aneuploid) to affect prognosis significantly (p < 0.001). Deaths resulting from tumor were exclusively observed among patients with atypical (eight of 40) or DNA aneuploid carcinoids (eight of 22). Six patients were alive with persistent tumor manifestations 3 to 20 years after initial diagnosis, four with DNA diploid primary carcinoids. The presence of lymph node metastases alone was not associated with poor prognosis as long as the primary tumor or the related metastases showed a diploid DNA content. DNA cytophotometry thus might be regarded as an adjunctive prognostic criterion in individual carcinoid cases.

Bronchial carcinoid tumor presenting as a thyroid nodule: an unusual clinical manifestation

Although rare, carcinoid tumors may present as thyroid metastatic nodules. We describe two patients with an undiagnosed bronchial carcinoid tumor, who presented as a thyroid nodule. Pathological examination of these nodules was diagnostic. Chemotherapy was indicated despite the dissemination of the tumors. The patients have an excellent quality of life. They are asymptomatic and alive, 18 and 24 months after diagnosis, respectively. In one case, chemotherapy obtained an important reduction in the size of the tumoral lesions but the other case showed no regression. Octreotide (SMS 201-995) was used in the case with carcinoid syndrome, with an excellent response.

Typical and atypical bronchopulmonary carcinoid tumors: a clinicopathologic and KI-67-labeling study

Expression of a proliferating antigen by KI-67 immunohistochemistry was analyzed with a SAMBA 2005 computer-assisted image processor (Traitement de l'Information for des Techniques Nouvelles, Grenoble, France) in 47 surgically resected bronchopulmonary carcinoids embedded in paraffin. The clinicopathologic characteristics and KI-67 labeling, expressed in percentage of stained nuclear surface relative to the total nuclear surface, of 31 typical carcinoids and 16 atypical carcinoids were compared and assessed with respect to patient survival. The proliferation status was significantly higher in histologically atypical than in typical carcinoids. Moreover, using a 4% cutoff, we observed a significant difference for the 4-year overall survival rate. Semiquantitative analysis of the proliferation index by KI-67 immunostaining seemed to be an effective means of identifying high risk subsets among patients with histologically atypical carcinoids and for whom adjuvant chemotherapy could be proposed.

Bronchoscopic therapy in patients with intraluminal typical bronchial carcinoid

OBJECTIVE

To study the efficacy of bronchoscopic therapy in patients with intraluminal typical bronchial carcinoid.

DESIGN

Retrospective analysis of the data of patients with bronchial carcinoid, treated primarily with bronchoscopic techniques such as Nd-YAG laser in various hospitals in the Netherlands.

SUBJECTS

Eleven patients with pulmonary complaints, ages 22 to 60 years, who were found to have intraluminal typical bronchial carcinoid. BRONCHOSCOPIC INTERVENTIONS: Six of the 11 patients received Nd-YAG laser treatments, one received Nd-YAG laser plus photodynamic therapy, and the other four had mechanical tumor removal.

RESULTS

Six patients were surgically treated after bronchoscopic therapy. The resected specimens showed no residual carcinoid. Median follow-up has been 70 months (range, 9 to 170 months). Five patients were not surgically treated after bronchoscopic therapy. Follow-up has been 27 to 246 months (median, 47 months) without signs of recurrence.

CONCLUSIONS

In 11 patients with typical, intraluminal, bronchial carcinoids, bronchoscopic treatment seemed to result in excellent local control, with surgical proof of cure in 6 of 11 patients. Bronchoscopic approach may provide a tissue-sparing alternative for bronchoplastic surgery in a subset of patients with typical intraluminal bronchial carcinoids.

Carcinoid tumors of the lung: do atypical features require aggressive management?

Atypical carcinoids are an intermediate form of tumor between low-grade malignant typical carcinoid and high-grade malignant small cell carcinoma, which represent the two ends of the spectrum of neuroendocrine bronchopulmonary tumors. Between 1983 and 1993, 27 patients with atypical carcinoids underwent surgical treatment. The histologic diagnosis of an atypical carcinoid was established if the criteria proposed by Arrigoni and associates were fulfilled. Seven pneumonectomies, 16 lobectomies, 2 segmentectomies, and 2 wedge resections were performed. Thirteen patients (48.1%) had regional nodal metastases and 6 patients (22%) had N2 disease at the time of surgical therapy. Distant metastases developed in 5 patients (18.5%) after initial treatment. The 10-year survival in patients with an atypical carcinoid was 49%, versus the 84% 10-year survival rate observed in patients with a typical carcinoid. We conclude that the aggressive behavior of atypical carcinoids precludes the use of limited surgical resection and requires a more aggressive approach, with lobectomy and mediastinal lymph node dissection constituting a minimal procedure. The same criteria used for well-differentiated lung carcinoma should apply to this form of neuroendocrine lung tumor. Adjuvant chemotherapy is recommended for patients with stage III or distant metastases.

Bronchial carcinoid tumors

Bronchial carcinoid tumors, termed (incorrectly) "bronchial adenomas" in the past, are uncommon pulmonary neoplasms. These tumors are currently classified as neuroendocrine in origin because of their potential to form and sometimes secrete a variety of chemical substances. Overall, approximately 75% of bronchial carcinoid tumors arise in the lobar bronchi, 10% occur in the main-stem bronchi, and 15% originate in the periphery of the lung. Well-differentiated carcinoid tumors constitute almost 90% of all bronchial carcinoids. Atypical carcinoid tumors have a higher malignant potential than do typical bronchial carcinoids. The carcinoid syndrome is rarely, if ever, associated with carcinoids limited to the tracheobronchial tree. Occasionally, Cushing's syndrome due to ectopic hormone production is caused by bronchial carcinoid tumors. More than 75% of bronchial carcinoids are detected on conventional posteroanterior chest roentgenograms. Computed tomography may help disclose small neoplasms that are occult on conventional roentgenography, particularly in the assessment of patients who have Cushing's syndrome due to ectopic hormone production. Pulmonary resection is the treatment of choice for bronchial carcinoids. The prognosis is related to the pathologic grade and stage of the tumor.

Atypical lung carcinoid with GFAP immunoreactive cells

A case of atypical carcinoid with peculiar histological and ultrastructural pattern and immunohistochemical phenotype is presented. The neoplasm is composed of three types of cells. Type 1 cells are small to medium sized, fusiform, with scarce cytoplasm and are arranged in fascicles. Type 2 cells are cuboidal and line acinar structures. Type 3 cells have more abundant eosinophilic cytoplasm, larger nuclei and are arranged in fascicles intersecting with fascicles of type 1 cells, and sometimes surround acinar structures. The three cell types are present both in the primary lesion and in its lymph node metastases. Immunohistochemistry demonstrates immunoreactivity of all cell types for general neuroendocrine markers. Cytokeratin immunoreactivity is more prominent in type 1 and 2 cells, and is only focally expressed in type 3 cells. Type 3 cells are also immunoreactive for glial fibrillary acidic protein (GFAP), alpha-actin, S-100 protein, vimentin. Electron microscopic examination confirms the neuroendocrine nature of the cells, and show that type 3 cells have prominent bundles of intermediate filaments, electron-dense granules and junctional complexes. To our knowledge, this is the first case of atypical lung carcinoid with GFAP immunoreactivity. The nature of type 3 GFAP positive cells is unclear. There are some clues pointing to their sustentacular nature, and other ones pointing to a myoepithelial origin, but the data are inconclusive. Type 3 cells may be the malignant counterpart of sustentacular cells seen in typical carcinoids, but their GFAP positivity and the presence of electron-dense granules are very unique features, which differentiates them from sustentacular cells. Alternatively, their unusual GFAP + immunohistochemical phenotype may be due to aberrant expression of cytoskeletal proteins.

Prognostic value of nucleolar organizer regions in neuroendocrine tumours of the lung

The value of the number and size of the nucleolar organizer regions (NORs) as prognostic indicators in human neuroendocrine lung tumours was evaluated in a quantitative study of 57 cases, including 33 small cell carcinomas (SCLCs), 9 well-differentiated neuroendocrine carcinomas (WDNECs) and 15 "classic" carcinoids. NORs were visualized on paraffin sections by an argyrophilic technique (AgNOR) and measured by automatic image analysis. In each case, the mean number and area of AgNORs were evaluated; the results were compared with clinical follow-up and survival. AgNOR values for both number and area were significantly higher in SCLCs than in WDNECs and carcinoids. WDNECs had insignificantly higher AgNOR values than carcinoids. Among SCLCs, AgNOR values of the oat cell subtype and the intermediate cell subtype did not differ significantly. Regardless of the histological tumour type, AgNOR values strongly correlated with prognosis, with more and larger AgNORs indicating a more progressive clinical course. In the present study we demonstrate for the first time that the biological behaviour of neuroendocrine lung tumours is correlated with the number and size of AgNORs. Thus the measurement of AgNORs may serve as an additional prognostic indicator in these neoplasms, particularly in the separation of SCLCs from WDNECs with a more favourable prognosis.

Prognosis of resected well-differentiated neuroendocrine carcinoma of the lung

Among lung tumors, well-differentiated neuroendocrine carcinomas are often misdiagnosed or may go unrecognized. Nineteen cases of well-differentiated neuroendocrine carcinoma (WDNC) were assessed at the National Cancer Institute of Milan over a ten-year period. There was only one woman and the age range was 50 to 77 years. Most of the patients were smokers (83 percent). All tumors were radically resected. There were 12 lobectomies, two sleeve-lobectomies, three bilobectomies, one pneumonectomy, and two segmentectomies (one patient had two synchronous WDNCs). There was neither operative mortality nor major complications. Sixteen tumors were stage 1, three were stage II, and one was stage IIIa. Five patients had adjuvant chemotherapy (cyclophosphamide, doxorubicin, and vincristine [CAV] regimen). One patient was given local or regional radiotherapy. In ten patients the tumors recurred, even though four had had adjuvant treatment. The brain was the first site of metastasis in seven cases. The pathologic stage seemed not to be closely related to the appearance of metastases (six patients with stage I disease had recurrences). Only two patients with recurrence were still alive 12 and 103 months after the procedure. The percentage of survival for patients with stage I disease after more than 100 months was 68 percent. WDNC is similar to small-cell lung carcinoma (SCLC) with regard to the neurotropism of metastases. Surgery is curative for more than one half of the patients with localized disease. Therefore, multimodal therapy, probably based on tumor behavior and investigations of tumor markers, is advisable.