non-small cell carcinoma

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Related to non-small cell carcinoma: NSCLC

bronchogenic carcinoma

lung cancer; although the term was formerly limited to malignant neoplasms arising from the epithelium of a bronchus or bronchiole, it is now applied generally to any primary malignancy of the lung or bronchial tract. Lung cancers are divided on the basis of predominant cell type into small cell carcinomas (15-25%) and non-small cell carcinomas (75-85%). Some tumors contain both cell types. Not included in this dichotomy are a small number (2-3%) of miscellaneous tumors (carcinoid, cylindroma, mucoepidermoid carcinoma). Small cell carcinomas of the lung tend to grow rapidly and metastasize early. They often produce hormones and antibodies capable of inducing paraneoplastic conditions such as hypercalcemia, Cushing syndrome, and myasthenia. Non-small cell carcinomas are subdivided into adenocarcinomas (50-60%; the most common type in women and nonsmokers), glandular cancers that usually arise peripherally, produce mucin, form tubular or papillary structures, and metastasize widely and early; squamous cell carcinomas (30-40%), which tend to develop centrally and in lower lobes and to metastasize more slowly; and the highly anaplastic large cell carcinomas (10%), which grow rapidly and produce carcinoembryonic antigen (CEA).

Bronchogenic carcinoma is the leading cause of cancer deaths in the U.S. in both men and women, and the most common cancer in men world-wide. About 200,000 new cases of lung cancer are diagnosed each year in this country. The 5-year survival rate is 10-15%, depending on cell type. The increase in the incidence of lung cancer in the U.S. during the early 20th century closely followed the increase in cigarette sales, a fact first noted by Ochsner and DeBakey in 1941. A fall in the male:female ratio of lung cancer incidence began in 1935 and accelerated steadily with the increase in smoking among women. The age-adjusted death rate from lung cancer in women doubled between 1965 and 1974, and in 1987 bronchogenic carcinoma surpassed carcinoma of the breast as the most common fatal malignancy in women. Currently, about 90% of lung cancer deaths are directly attributable to cigarette smoking, and 25% of lung cancer in nonsmokers is due to involuntary (passive) smoking. About 11% of regular cigarette smokers develop lung cancer. Cancer risk is related to the age at which smoking began, the number of cigarettes smoked, and the depth of inhalation. Smoking cessation reduces the risk. Because adenocarcinoma of the lung is more common in families with other cancers and with inherited lung disorders, a genetic predisposition is probable. (Some people may also be genetically predisposed to nicotine addiction.) Inhalation of industrial carcinogens (particularly asbestos, silica, chromium, nickel, and polyvinyl chloride) and exposure to ionizing radiation or radon are other known causes. Bronchogenic carcinoma may encroach on the bronchial lumen or may invade adjacent lung parenchyma. The principal sites of metastasis are mediastinal lymph nodes, liver, brain, and bone. Complications include superior vena cava syndrome, esophageal obstruction, pericardial tamponade, phrenic nerve palsy, and Pancoast syndrome. Early symptoms (gradual onset of cough or change in a chronic cough, dyspnea, wheezing) may be wrongly attributed to smoking or to lower respiratory infection. By the time more ominous symptoms (hemoptysis, anorexia, weight loss, chest pain) occur, the condition is usually advanced and inoperable. Chest x-ray or computed tomography (CT) typically shows a solitary nodule and may also reveal evidence of atelectasis, pneumonic infiltrate, involvement of mediastinal nodes, or pleural effusion. MRI may detect invasion of vertebrae, spinal cord, or mediastinal structures. The diagnosis of carcinoma is confirmed by the finding of malignant cells in sputum, bronchial washings, or pleural fluid, or in biopsy material obtained by bronchoscopy, percutaneous needle aspiration, thoracoscopy, mediastinoscopy, or thoracotomy. Some studies suggest that screening high-risk populations (for example, smokers aged 60 or older) by means of CT or sputum cytology reduces morbidity and mortality. Low-dose helical (spiral) CT is more sensitive than standard chest radiography in detecting lung cancer, but may not be cost effective even in high-risk populations. Surgical excision is the treatment of choice for bronchogenic carcinoma. Lung-sparing procedures (sleeve lobectomy, segmentectomy, wedge resection) may permit surgical excision in patients with limited pulmonary reserve but are associated with higher recurrence rates. Radiation therapy and chemotherapy with cisplatin, mitomycin, vinca alkaloids, ifosfamide, and etoposide are chiefly of use as palliative measures in advanced or inoperable disease.

Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
We reflexively test all nonsquamous non-small cell lung carcinomas, including adenocarcinomas, combined adenosquamous carcinomas, and non-small cell carcinomas, not otherwise specified, for EGFR mutations and ALK gene rearrangements.
of Concordance Reference Diagnosis Responses Rate, % Adenocarcinoma 186146 96.0 Lymphoma/hematopoietic 50 081 94.8 malignancy Mesothelioma 22 369 94.2 Non-small cell carcinoma 18 774 94.8 Small cell carcinoma 21 855 98.4 Normal or reactive 14 550 83.3 Table 3.
Therefore, it is suggested that the RNAscope assay be performed for both TTF-1 and napsin A in (1) TTF-1- and napsin A- by IHC in pulmonary non-small cell carcinoma; and (2) [CK7.sup.+] but both [TTF-1.sup.-] and napsin Aby IHC in carcinoma with a clinical suspicion of a lung origin when working on a tumor with unknown primary.
However, many undifferentiated or poorly differentiated non-small cell carcinomas, especially those with small tissue biopsies or fine-needle aspiration samples, may require additional ancillary studies, such as IHC, to further clarify their morphologic classification.
In summary, cytotechnologists had significantly higher concordance rates for non-small cell carcinoma and adenocarcinoma, while pathologists performed better for carcinoid tumor (Table 3).
Of note, the frequency of EGFR mutations in non-small cell carcinoma of the lung has been reported to be 33.2% in Latin American countries overall, which is similar to the Asian population.
Gastrin-releasing peptide receptor expression was noted in bronchial epithelium and submucosal gland epithelial cells (not quantified) from small cell and non-small cell carcinoma cases.
Interpretation Distribution for Adenocarcinoma (Including Bronchioloalveolar Carcinoma) Cases (n = 13 231) Participant Reference Frequency % Interpretation Infectious/inflammatory 7224 54.6 bronchioloalveolar Non-small cell carcinoma 3513 26.6 Squamous cell carcinoma 707 5.3 Metastatic carcinoma, not 526 4.0 otherwise specified Carcinoid 409 3.1 Small cell undifferentiated 346 2.6 carcinoma Metastatic melanoma 154 1.2 Normal/reactive 112 0.8 Infectious/inflammatory 56 0.4 Specific infections/ 49 0.4 granulomatous Mesothelioma 43 0.3 Hamartoma 40 0.3 Lymphoma/hematopoietic 17 0.1 malignancy Unsatisfactory 15 0.1 Sarcoma, not otherwise 12 0.1 specified Other malignancy 8 0.1 Table 5.
Subtyping of undifferentiated non-small cell carcinomas in bronchial biopsy specimens.
Genetic alterations such as deletions of 9p are some of the most frequent events in other non-mesothelioma tumor types including non-small cell carcinomas and sarcomas of the lung.