Pathology of lung cancer
Pathology of lung cancer, lung cancer from the origin of the endoderm from pluripotent cells can be made to more than one phenotype (phenotype) in the direction of differentiation, according to the World Health Organization has developed the lung cancer histological type, squamous cell carcinoma of the lung is divided into , small cell lung cancer, adenocarcinoma, squamous carcinoma and large cell undifferentiated carcinoma five categories. Used to be mistaken for benign bronchial adenoma, it is low-grade malignant tumor, divided into carcinoid (80%), cylindrical tumor (adenoid cystic carcinoma) and mucoepidermoid carcinoma.
Some of the recent study found that lung cancer compared with the histological composition change. Vincent, etc. Review the northeastern United States from 1962 to 1975 a total of 1682 cases of histological types of lung cancer was found in 1962, lung cancer, adenocarcinoma, alveolar cell carcinoma, small cell lung cancer, large cell lung carcinoma and undifferentiated carcinoma were 48.6 %, 17.6%, 1.4%, 18.9%, 10.8% and 2.7%. To 1975, the proportion of squamous cell carcinoma has decreased, while the proportion of adenocarcinoma has increased 25.5% and 29.8%. The proportion of adenocarcinoma increased with the following factors: female lung cancer increased. 1967 years after the histological diagnosis of lung cancer indication for change. occupational and environmental factors. In Japan, the proportion of lung cancer in the large. 18ao Tanaka 1983, reviewed the 1950 autopsy results of 282 cases of lung cancer and found that the proportion of adenocarcinoma has decreasing trend, from 1950 to 1964 was 57.3%, while 19 751 1983 39.8%; squamous cell carcinoma has increased the proportion of the corresponding , rose to 24.1% from 17.3%.
Dai Chengqing summary of 2740 cases of lung cancer and other pathological types of distribution, that most of the squamous cell carcinoma, accounting for 50.7%; women with cancer the most, 52.6%; the whole group, 33.6% of lung cancer, were similar in Japan . Medical Oncology Hospital in January 1965 ~ December 1966 in the treatment of lung cancer, adenocarcinoma 38%; January 1975 ~ December 1976 accounted for 32.3%, in January 1985 ~ December 1986 33.8% shows little change in 20 years. Liao Meilin statistical Shanghai from 1984 to 1985, occurred within one year of the new 940 cases of lung cancer, squamous cell carcinoma 35.1%, adenocarcinoma 35.7%; women with adenocarcinoma most (47.6%), most men with squamous cell carcinoma (44.6%).
Small cell lung cancer in young people the most, also reported in adenocarcinoma and more. Medical Oncology Hospital, 135 cases of young people under the age of 30, lung cancer, small cell lung cancer, 45.6%; 20 years of age in 13 cases of lung cancer, 9 cases of small cell lung cancer, no case of squamous cell carcinoma.
Of lung cancer in smokers is mainly squamous cell carcinoma, small cell lung cancer and large cell lung cancer. With the increase or decrease in the number of smokers, lung cancer histological types of composition ratio will change. Since 1991, Auerbach et al reported that changes in smoking habits, the United States before 1978 accounted for 30.7% of peripheral lung cancer, from 1986 to 1989, was promoted to 42%; lung cancer rose to 20.3% from 9.3%; central lung cancer down from 69.3% 57.3%.
Histological type of lung cancer and tumor biological behavior, prognosis, and its X-ray findings also have some relationship with non-small cell lung cancer for surgery primarily, while small cell lung cancer Zeyi systemic chemotherapeutic regimens.
Pathology of lung cancer, (a) squamous cell carcinoma
Histological features of squamous cell carcinoma is a keratinized epithelial cells, keratin pearls and intercellular bridges. Most (60%) occurred in the proximal segmental bronchi, so most of the performance of the central type of lung cancer, resulting in signs of airway obstruction. Only sputum-positive early stage and no positive X-ray findings, the limitations can be presented after obstructive pulmonary emphysema, and then was obstructive pneumonia, atelectasis. Often after blocking alveolar type protein or lipid containing macrophage accumulation, interstitial fiber changes, they can have bronchiectasis, mucus impaction, but also for true infection. Peripheral squamous cell carcinoma accounts for about 40%, often greater when the tumor was found. Often central necrosis of tumor, tissue loss and the formation of thick irregular cavities 10% to 15%.
The slow development of squamous cell carcinoma, 40% may have hilar or mediastinal lymph nodes only occur on the chest late shift. Prognosis than other types of lung cancer as well.
Lung pathology (b) small-cell lung cancer
On the morphology of small cell carcinoma is divided into oat cell (or class of lymphocytes) type and intermediate type (small spindle cells, small polygonal cell). Their biological behavior of no great distinction. The main features of the cell is small, little cytoplasm, the cell basic exclusively nuclear, nuclear deeply stained, often mitosis, nucleoli small or absent. Tumors along the small blood vessels flaky, grid-like, false daisy-like arrangement of groups, very few inflammatory host response, often necrosis. 20% of small cell lung cancer non-small cell lung cancer within the composition. Small cell lung cancer after chemotherapy or radiotherapy, primary tumor or metastasis and recurrence within the lesion can occur alone or in combination of non-small cell carcinoma. Alone and non-small cell carcinoma were prompted by small cell lung cancer has been completely eliminated, but not small cell carcinoma of the components appear or grow up. Small cell carcinoma and large cell carcinoma of the coexistence of the worst prognosis.
Small cell lung cancer occur in the large bronchi, along the submucosal growth, 70% to 80% of central cancer. That 80% of newly diagnosed mediastinal or hilar lymph node metastases. 100% of autopsy intrathoracic lymph node metastases. Blood of small cell lung cancer metastasis occurs early, the liver, abdominal lymph nodes, adrenal glands, central nervous system and bone marrow transfer more common. 2 / 3 of cases have been transferred at the initial visit. Small cell lung cancer and smoking are closely related, especially youth to start smoking, and especially heavy smokers. In all types of lung cancer, the fastest-growing small-cell lung cancer, the worst prognosis.
Recent years histochemistry, immunohistochemistry and electron microscopy of the development, that the carcinoid, atypical carcinoid and small cell lung cancer cells were a precursor uptake and decarboxylase plastic features in common, cells were argyrophilic particles cytosolic peptides produced from the function, collectively APUD-type cell tumor or neuroendocrine tumors. The three lung cancer cell differentiation, biological behavior and clinical, X-ray findings vary, remains to be further study.
Lung pathology (c) adenocarcinoma
Histological features of adenocarcinoma are: cancer cells often with secretion; the formation of tubular or papillary structures. Slow growth of adenocarcinoma, the majority (75%) peripheral cancer, mostly in 4cm below. Well-differentiated adenocarcinoma, the cells were well-arranged tubular or glandular-like structures, cells, or glandular cavity containing mucus or glycogen. Differentiated adenocarcinoma cells were arranged in solid nests, cords or mass, but still common tubular or glandular-like structure formation. Showed poorly differentiated adenocarcinoma of the major distribution of nests or diffuse sheets, rare tubular or glandular-like structure formation. Often in adenocarcinoma of the center of fibrosis or scar formation. Some cancer is very rich in collagen fibers. Often pleural invasion, lymph node metastasis and vascular invasion.
Metastasis in early adenocarcinoma of blood. Mathews reported 30 cases of adenocarcinoma, 1 month after surgery for autopsy who died, 43% had adrenal gland, central nervous system, abdominal lymph
nodes, bone and contralateral lung metastases. Another group of 110 cases of adenocarcinoma of the autopsy, mediastinal lymph nodes accounted for 80% of intrathoracic lymph nodes and more small and less, 60% of the contralateral lung metastases, adrenal metastasis 57%, 37% of the central nervous system metastases, metastases confined to the chest in only 3%. Some of the first diagnosis of lung cancer symptoms in patients with brain metastasis was mistaken as a primary brain tumor and craniotomy. Since the early shift, so the primary tumor adenocarcinoma While smaller, easy surgery, but the prognosis is poor, only slightly better than the small cell carcinoma.
Bronchioloalveolar carcinoma is a subtype of lung cancer. Cancer or high columnar form was false. Nuclear morphology was consistent or polymorphism. Abundant cytoplasm containing vacuoles or mucus. Tumor cells in the alveolar wall to support creeping growth, filling the existing alveoli, alveolar formation of papillary tumor structure. Lung cancer can be divided into Council refuse nodules, segmental and diffuse type of three.
Gland tumor formation in any tissue is similar, it is sometimes difficult to identify lung cancer is the primary or secondary, are especially difficult, and digestive tract cancer and pancreatic and bile duct cancer, lung metastasis identification. Note peritumoral bronchial epithelial dysplasia or carcinoma in situ with all other transitional changes in differentiating primary and secondary are be helpful.
Pathology of lung cancer (four) large cell lung cancer
Tumor cells were large, pleomorphic, non-differentiation tendencies, nuclear irregularity, large and darkly stained, with prominent nucleoli, cells arranged in sheets or nests, without keratinization, intercellular bridges, but mainly by the exclusion of other tumor diagnosis. Tumors located in the periphery, grow fast, forming a huge mass, which may have hemorrhage and necrosis, but rarely form a hollow.
Pathology of lung cancer (V) complex cancer
Had more than one histological type, squamous carcinoma to see more. As mentioned above within a small cell carcinoma non-small cell carcinoma components, suggesting that starting from the full potential of lung cancer cells (totopotential cell) possible.
Pathology of lung cancer (six) carcinoid
Occur in the large bronchial submucosa (90%), internal and external to the tube growth, and often the formation of chronic obstructive pulmonary disease, chronic lung disease or purulent bronchiectasis. Carcinoid tumors occur in women. Rich in blood vessels, nuclear polymorphism was, mitosis less. There is only 5% of the clinical carcinoid syndrome. Prognosis is good, five-year survival rate was 90%. A typical class is not cancer cells were pleomorphic nuclei, mitotic number, necrosis and more common than lymph node metastasis, prognosis and adenocarcinoma is similar.