PURPOSE: To evaluate the incidence of bronchial carcinoid tumor (BCT) in population affected by various lung tumors, retrospectively reviewed between 1986-2001, and to emphasize the radiographic patterns if they are characteristic. MATERIALS AND METHODS: In the above mentioned period, chest x-ray and CT were performed in 1110 patients, both male and female, affected by lung neoplasms. RESULTS: 20 patients were affected by BCT (16 males, and 13 females), aged between 26 and 75 years (mean age 57.5), with histopathologic diagnosis of typical (9 cases, 31%) and atypical (20 cases, 69%) bronchial carcinoid tumors. Localized right lung lesion were as follows: 7 cases in superior, 9 in middle and 4 in inferior lobes; in the left lung, 5 cases in superior, and 4 in inferior lobes. Size of the lesions was as average 2.4 cm in diameter (with a range of 0.5-12 cm). On x-ray and CT images, BCT appeared as a well marginated nodule, of which 9 were peripheral and 20 central. DISCUSSION AND CONCLUSION: BCT are classified as neuroendocrine carcinomas,and are divided in typical and atypical forms, with variable grade of malignancy. Central neoplasms are symptomatic due to bronchial obstruction (i.e., pneumonia, atelectasis, bronchiectasis, emphysema and/or lung abscess); if airway obstruction is partial, then cough, wheezing and recurrent pulmonary infections occur. Peripheral tumors are generally asymptomatic and they are discovered occasionally, when chest x-ray is made for other reasons. Radiographic features are similar in typical and atypical BCT. In central tumors a rounded well circumscribed hilar mass is noted, with lobulated or bumpy margins. Central cavitation is not referred to. Peripheral BCT appear as a solitary nodule, inferioer then 3 cm in size, marginated, surrounded by normal pulmonary tissue. Signs and symptoms of BCT are evasive and vague. No current clinical or laboratory procedures are useful in confirming the diagnosis; particularly, no imaging modalities are able to differentiate between BCT and other pulmonary tumors. For this reason, a clinical radiologic endoscopic and histopathologic approach is necessary. CT is more sensiticve then conventional radiography, especially in detecting small lesions, calcification and enlarged lymph nodes. MRI may be useful in those patients, who cannot tolerate IV contrast media. Scintigraphy may be employed in discovering relapses and long standing metastases.

TTF-1 expression is specific for lung primary in typical and atypical carcinoids: TTF-1-positive carcinoids are predominantly in peripheral location.Hum Pathol. 2004 Jul;35(7):825-31.

Thyroid transcription factor (TTF)-1 expression in neuroendocrine tumors (NETs) has not been studied as widely as that in non-NETs, with the exception of small cell carcinomas, in which TTF-1 is highly sensitive but not specific for a primary lung tumor. The reported incidence of TTF-1 expression in pulmonary carcinoids has also been highly variable in the literature. To evaluate the expression of TTF-1 in NETs and potential value of TTF-1 in distinguishing pulmonary NETs from those of extrapulmonary origin, we performed an immunohistochemical study by using semiquantitative analysis on formalin-fixed, paraffin-embedded sections from 111 NETs, including 80 pulmonary (11 carcinoid tumorlets [TLs] or foci of neuroendocrine cell hyperplasia [NEH], 36 typical carcinoids [TCs], 17 atypical carcinoids [ACs], 16 large cell neuroendocrine carcinomas [LCNECs]), 13 thymic (3 TCs, 8 ACs, 2 LCNECs), 17 gastrointestinal or pancreatic (13 TCs, 4 ACs), and 1 ovarian (LCNEC). Pulmonary carcinoids were subdivided into those with central and those with peripheral location. TTF-1 positivity was seen exclusively in pulmonary NETs and was significantly higher in NEH or TLs (72.7%) than in TCs (27.8%), ACs (29.4%), and LCNECs (37.5%; P = 0.03). All extrapulmonary NETs were uniformly negative for TTF-1 staining. Interestingly, 12 of 14 TTF-1-positive pulmonary TCs and ACs had a peripheral location with spindle cell morphology, as did all cases of TL, a purported precursor of peripheral carcinoids. In conclusion, TTF-1 expression was 100% specific, though not so sensitive, for the lung primary in TCs and ACs and possibly also in LCNECs. Prevalent TTF-1 positivity in TLs and peripheral carcinoids suggest that they may be histogenetically distinct from the central carcinoids, which are typically composed of TTF-1-negative, more rounded cells.

Transbronchial lung biopsy as a diagnostic method of peripheral lesions.Pneumonol Alergol Pol. 2004;72(11-12):482-6.

The aim of the study was to assess the diagnostic yield of transbronchial lung biopsy (TBLB) without fluoroscopic guidance in peripheral lesions of diameter 2,5-6 cm. TBLB was performed in 65 consecutive patients without abnormalities in bronchial tree in standard bronchofiberoscopy and preceded by computed tomography (CT). The CT guidance helped to select the segment of lung to be biopsied. In 39 patients (60%) TBLB enabled to diagnose 36 cases of lung cancer, 2 cases of carcinoid and 1 case of malignant lymphoma. There were 26 cases (including 21 cases of lung cancer) undiagnosed by means of TBLB. In 24 patients the diagnosis was established by means of other methods like transbronchial needle aspiration (TBNA)--5 cases, thin needle biopsy (TNB)--12 cases, open lung biopsy (OLB)--7 cases and in the remaining 2 patients a regression of clinical and radiological features was observed. Transbronchial lung biopsy was found to be efficient diagnostic method in peripheral lesions higher than 2,5cm. However, in 40% of cases this technique doesn't allow to establish a diagnosis. This, in turn implicates the necessity for further diagnostic procedures including TBNA, TNB or even OLB.

Clinicopathological analysis of clinical N0 peripheral lung cancers with a diameter of 1 cm or less.Thorac Cardiovasc Surg. 2004 Aug;52(4):196-9.

BACKGROUND: The appropriateness of limited resection for small-sized lung cancer continues to be debated. It is not yet clear whether tumor size alone is a reliable indicator for limited resection. METHODS: From 1980 to 2002, 27 patients with clinical N0 peripheral lung cancers having diameters of 1 cm or less underwent pulmonary resection. Clinicopathological features of these cases were reviewed retrospectively. RESULTS: Histological analysis showed that there were 23 cases of adenocarcinoma (81.5 %), two large cell carcinomas (7.4 %), and two carcinoid tumors. Twenty-two cases were classified as pathological stage 1, one was stage II, and four were stage III. Four patients (14.8 %) had lymphatic vessel invasion, three (11.1 %) had lymph node metastasis, and two (7.4 %) had intrapulmonary metastasis. The 5-year disease-free survival rate was 76.6 %. CONCLUSIONS: It is impossible to predict the effectiveness of an intentional limited resection for lung cancer using only tumor size.

Bronchopulmonary carcinoid tumours.Minerva Chir. 2002 Aug;57(4):403-23.

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 ones. They usually affect patients in the 3rd through the 7th decade of life who are often symptomatic with cough, hemoptysis or obstructive pneumonia. Rarely, the initial symptoms are related to the secretion of hormones causing carcinoid or other endocrine syndromes. Bronchial carcinoids radiologically manifest as hilar or perihilar masses, with or without associated atelectasis, pneumonia or bronchiectasis. At CT-scan the relationship of these tumors with the bronchial tree is usually seen, and they show contrast enhancement or calcification. Even if the radiological signs may be suggestive for bronchial carcinoid, the definitive diagnosis is reached only by the tissue sampling. Bronchoscopic biopsy is the more effective way to identify the nature of carcinoid tumors because of their frequent central location. The treatment of choice is the surgical resection which should be carried out with maximum respect for the residual lung and bronchial tissues. Endoscopic ablations in well defined cases, bronchotomy and lung resections with or without bronchoplastic procedures have been described. Hilar and mediastinal lymph node sampling and examination should be ever performed during open procedures. Positivity of the nodal tissues could influence the resection procedure and is related with the prognosis, specially for the atypical carcinoids. Chemo- and radiation therapy are not effective in improving the long-term outcome in those patients with advanced disease. The long-term outcome is strictly related with the histological subtype and the lymph node status. Local recurrences and distant metastases are more frequent in the atypical carcinoids which manifest a more aggressive behavior. During the last decade, the importance of the use of somatostatine analogues (octreotide) in the staging, early detection of the recurrent disease and its management such as that of the associated carcinoid syndrome became clear.