I. Clinical manifestations
Almost 2/3 of lung cancer patients are already in advanced stage (stage III or IV) when they are diagnosed. 95% of patients in Zhengzhou Cancer Hospital can have clinical examination results, and primary tumor, metastasis, systemic symptoms or tumor accompanying symptoms can be the first symptoms of patients.
The first symptoms caused by primary tumor account for 27%, and the symptoms are related to the site of primary tumor. Central type lung cancer manifests as irritating dry cough, breath-holding, recurrent episodes of pneumonia in the same area, hemoptysis or asthma, symptoms of laryngeal recurrent nerve, phrenic nerve compression or superior vena cava compression syndrome. Peripheral tumors are more commonly associated with chest pain, breath-holding or pleural effusion. Large peripheral type lesions, central necrosis, and cavities eventually present with lung abscess-like manifestations, a common symptom grouping for primary lung cancer.
Distant metastatic lesions cause 32% of the first symptoms. Common distant metastatic sites include: lymph nodes, adrenal glands, liver, bone, lung, brain and chest wall, producing some corresponding symptoms, indicating that lung cancer has reached advanced stage, such as: tumor near the mediastinal surface may invade phrenic nerve, causing ipsilateral diaphragm paralysis, showing elevated position of diaphragm and abnormal breathing movement under fluoroscopy; invade ipsilateral laryngeal recurrent nerve, causing hoarseness and hoarse voice. Invasion of the ipsilateral recurrent laryngeal nerve causes hoarseness, ipsilateral vocal cord paralysis and fixation in median position; compression of superior vena cava causes edema of the head, face and upper limbs, and angry veins; invasion of pleura. It can cause a large amount of hemorrhagic fluid in the pleural cavity and aggravate shortness of breath, or directly invade the chest wall and cause severe chest pain; lung cancer in the upper lobe tip is at the entrance of the thorax, also known as supraglottic sulcus cancer, which can invade and compress the brachial plexus nerve, cervical sympathetic ganglion and subclavian artery, producing a series of specific symptoms, such as numbness and pain in the ipsilateral upper limb, which gradually increases It is difficult to tolerate; muscles and skin show atrophic changes, venous rage and edema of upper limbs; and cervical sympathetic nerve syndrome such as ipsilateral ptosis, pupil narrowing, eye sunken, no sweating on the face.
10-20% of lung cancer patients have tumor-associated syndromes, the most common ones are small cell lung cancer and squamous carcinoma. Common tumor-associated syndromes include: osteoarthrosis of pulmonary origin syndrome (pestle and mortar finger, osteoarthrosis, periosteal hyperplasia, etc.), SIADH (syndrome of abnormal secretion of antidiuretic hormone), hypercalcemia, etc., and Cushing’s syndrome, myasthenia gravis or male breast enlargement. About 16% of patients have neuromuscular symptoms. Some patients have combined skin diseases such as scleroderma and acanthosis nigricans.
The clinical manifestation of lung cancer is closely related to the location, size, whether the cancer is compressing, invading adjacent organs and whether there is metastasis. If the cancer grows in the larger bronchial tubes, irritating cough often appears. The enlarged cancer affects the bronchial drainage and can cause pus sputum when it is secondary to lung infection. Another common symptom is bloody sputum, usually with blood spots or blood in the sputum or intermittent small amount of hemoptysis; some patients have important reference value for diagnosis even if they have bloody sputum once or twice. In some patients, due to large bronchial obstruction caused by tumor, symptoms such as chest tightness, shortness of breath, fever and chest pain may appear.
When advanced lung cancer compresses adjacent organs and tissues or distant metastasis occurs, it can produce.
① compression or invasion of phrenic nerve, causing ipsilateral diaphragm paralysis.
② Compression or invasion of the recurrent laryngeal nerve may cause hoarseness and paralysis of the vocal cords.
(3) Compression of the superior vena cava may cause venous rage in the face, neck, upper extremities and upper chest, subcutaneous edema, and increased venous pressure in the upper extremities.
④Invasion of pleura may cause pleural effusion, mostly bloody.
(5) Cancer invading the mediastinum and compressing the esophagus may cause difficulty in swallowing.
syndrome.
In a few cases of lung cancer, due to the endocrine substances produced by the cancer, non-metastatic systemic symptoms may appear clinically, such as osteoarthritis syndrome (pestle and mortar fingers, arthralgia, periosteal hyperplasia, etc.), Cushing’s syndrome, myasthenia gravis, male breast enlargement, multiple muscle neuralgia and other extra-pulmonary symptoms. These symptoms may disappear after resection of lung cancer.
II. Diagnosis
The diagnosis of primary bronchial lung cancer is based on symptoms, signs, x-ray manifestations and sputum cancer cell examination (sputum examination). Different steps should be taken in the diagnostic workup according to different situations.
(A) Negative X-ray and negative sputum examination
1.Anyone without symptoms but with three major high-risk factors (male, age ≥45 years old and smoking >400 cigarettes/year) should undergo 70-100mm fluorescent microscopic x-ray or chest fluoroscopy and sputum cytology examination half-yearly.
2. Anyone with hemoptysis or/and dry choking cough with three major high-risk factors should undergo repeated sputum cytology and be given regular anti-inflammatory therapy at the same time; fiberoptic bronchoscopy (fibronectomy) and televisual fluoroscopy can be considered. If repeated sputum examination or microscopy is still negative, it should be reviewed every two months for one year.
(B) Negative X-ray and positive sputum examination
1.Exclude upper respiratory tract and esophageal carcinoma
2.Perform fibrinoscopy, strive to peer into the sub-segment, and if there is suspicious local mucosal thickening, roughness or blood stains, brush inspection, flushing or puncture of bronchial wall mucosa should be performed in the area to search for cancer cells. If local unevenness or roughness is found, it should be considered for biting biopsy.
3.Conduct TV fluoroscopy and change the body position, focusing on small nodule foci in hidden areas.
4.If no lesion is found by the above examinations, sputum, electron microscopy and fibrinoscopy should still be repeated every two months. CT examination can also be performed, and subdivision can be made at suspicious places. Regular review should be continued for not less than one year.
(C) Positive X-ray and negative sputum examination
1.Patients with segmental or lobar pneumonia or obstructive pneumonia and suspected central lung cancer should undergo fibrinoscopy, including trans-fibrinoscopic biopsy (TBB), or selective bronchography; and repeatedly strengthen sputum examination.
2. Local tomography should be performed for mass or nodal lesions. Transbronchoscopic lung biopsy (TBLB), or percutaneous lung biopsy, or aspiration for cytological diagnosis should be performed if available.
3.Continuous sputum examination should be done at least twelve times.
4.If repeated sputum examination is still negative, and x-ray is highly suspicious of lung cancer, dissection and frozen section biopsy should be performed.
(D) Positive X-ray and positive sputum test
1.Actively make pre-surgical preparation.
2. If regional lymph node enlargement is suspected, frontal and lateral oblique stratification films can be taken. For limited stage small cell lung cancer, CT and lateral tilt stratification film, liver ultrasound, bone isotope scan and bone marrow aspiration into biopsy smear should be routinely used in large hospitals to facilitate the development of treatment plan.
III. Pathological profile
Lung cancer originates from the bronchial mucosa epithelium and those confined within the basement membrane are called carcinoma in situ. The carcinoma can grow into the bronchial lumen or/and adjacent lung tissues, and can spread through lymphatic, hematologic or transbronchial metastasis. The growth rate and metastatic spread of carcinoma are related to the biological characteristics of carcinoma such as histological type and degree of differentiation.
The distribution of lung cancer is more in the right lung than in the left lung, and more in the upper lobe than in the lower lobe. Carcinomas can occur from the main bronchus to the fine bronchus. Lung cancer originating from the main bronchus and lobar bronchus and located close to the hilum is called central lung cancer; lung cancer originating below the bronchus of the lung segment and located in the peripheral part of the lung is called peripheral lung cancer.
(I) Classification Clinically, lung cancer is generally classified into the following four types.
1.Squamous cell carcinoma (also called squamous carcinoma): it is the most common among all types of lung cancer, accounting for about 50%, and most of the patients are above 50 years old, with men accounting for most of them. Most of them originate from the larger bronchi and are often central lung cancer. Although the degree of differentiation of squamous carcinoma varies, it generally has a slow growth rate, a long disease course, and is more sensitive to radiation and chemotherapy. It first metastasizes through lymphatic metastasis, and hematogenous metastasis occurs later.
2.Undifferentiated carcinoma: It is second only to squamous carcinoma in incidence rate, mostly seen in men, with a younger age of onset. It generally originates from larger bronchi and is a central type of lung cancer. It can be divided into oat cell, small round cell and large cell types according to tissue cell morphology, among which oat cell is the most common. Undifferentiated carcinoma is highly malignant, grows rapidly, and has early lymphatic and hematologic metastasis, and is more sensitive to radiation and chemotherapy.
Adenocarcinoma: It originates from the mucosal epithelium of the bronchus, and a few originate from the mucus glands of the large bronchus. The incidence is lower than that of squamous and undifferentiated carcinoma. It occurs at a younger age and is relatively common in women. Most adenocarcinomas originate in the smaller bronchi and are peripheral type lung cancers. There is no obvious clinical symptom in early stage, but it is often detected during chest x-ray and appears as a round or oval mass, which usually grows slowly but sometimes bloodstream metastasis occurs early, while lymphatic metastasis occurs later.
4.Alveolar cell carcinoma: It originates from bronchial mucosa epithelium and is also called fine bronchial alveolar cell carcinoma or fine bronchial adenocarcinoma. The location is around the lung field. It has the lowest incidence rate among all types of lung cancer and is more common in women. The cancer cells grow along the bronchioles, alveolar ducts and alveolar walls without invading the alveolar septum. Lymphatic and hematogenous metastases occur later, but can spread to other lung lobes or invade the pleura via bronchioles. Alveolar cell carcinoma can be morphologically nodular or diffuse, the former can be a single nodule or multiple nodules; the latter morphology resembles pneumonia. The nodular type with limited lesion scope has better efficacy in surgical resection.
Only early diagnosis and early treatment can achieve better results, therefore, we should widely promote cancer prevention knowledge to the public. For adults over 40 years old, it is advisable to conduct chest X-ray screening once every six months. For those with suspicious symptoms, such as cough that does not go away, blood in the sputum and shadow in the lung, a series of detailed examinations should be conducted to make a clear diagnosis. For nodules ≤5mm found in the screening, they should be reviewed once every 3 months; nodules of 6-10mm should be biopsied by percutaneous puncture, and if biopsy is not possible, CT should be reviewed every 3 months; nodules >1cm should be biopsied.
Lung cancer currently adopts the clinical staging of TNM system published by the International Union Against Cancer in 1997 (Tables 4-6), which is only applicable to non-small cell lung cancer. Small cell lung cancer mostly adopts a two-stage system i.e.: limited type and extensive type. The limited type is defined as a lesion confined to one side of the chest with or without ipsilateral mediastinal or supraclavicular lymph node metastasis. It accounts for only 26% of small cell lung cancers. Extensive type is defined as a lesion that exceeds the scope of the limited type.