What are the clinical symptoms of lung cancer? Summary of clinical symptoms of lung cancer

Nowadays, many people suffer from lung diseases due to long-term tobacco smoking. Over time, lung cancer may develop. Lung cancer is divided into early and late stages. However, because many people discover it late, they will miss the best treatment time and our lives will no longer continue. So, what are the clinical symptoms of lung cancer?

(I) Local symptoms

Local symptoms refer to symptoms caused by the tumor itself irritating, blocking, infiltrating and compressing tissues as it grows locally.

1. Cough

Cough is the most common symptom, with 35% to 75% of patients having cough as the first symptom. Cough caused by lung cancer may be related to changes in bronchial mucus secretion, obstructive pneumonia, pleural invasion, atelectasis and other intrathoracic complications. When the tumor grows in the bronchial mucosa above the segment with a larger diameter and sensitive to external stimuli, it can cause a cough similar to that caused by foreign body stimulation, typically manifested as paroxysmal irritating dry cough, which is often difficult to control with general cough suppressants. When the tumor grows in the smaller bronchial mucosa below the segment, the cough is often not obvious or even absent. For patients who smoke or suffer from chronic bronchitis, if the cough becomes more severe, the frequency changes, and the nature of the cough changes, such as a high-pitched metallic sound, especially in the elderly, be highly alert to the possibility of lung cancer.

2. Blood in sputum or hemoptysis

Blood in sputum or hemoptysis is also a common symptom of lung cancer, accounting for about 30% of the first symptoms. Because tumor tissue is rich in blood supply and brittle in texture, blood vessels rupture and cause bleeding during severe coughing. Hemoptysis may also be caused by local tumor necrosis or vasculitis. The characteristics of lung cancer hemoptysis are intermittent or continuous, repeated small amounts of blood in sputum, or small amounts of hemoptysis, occasionally due to large blood vessel rupture, large cavity formation or tumor rupture into the bronchial and pulmonary blood vessels, leading to uncontrollable large hemoptysis.

3. Chest pain

About 25% of patients have chest pain as the first symptom. It often manifests as irregular dull pain or pain in the chest. In most cases, peripheral lung cancer invades the parietal pleura or chest wall, which can cause sharp and intermittent pleural pain. If it continues to develop, it will evolve into constant drilling pain. Mild chest discomfort that is difficult to locate is sometimes related to central lung cancer invading the mediastinum or involving blood vessels and peripheral bronchial nerves, and 25% of patients with malignant pleural effusion complain of dull chest pain. Continuous, sharp and severe chest pain that is not easily controlled by drugs often indicates that there has been extensive pleural or chest wall invasion. Persistent pain in the shoulder or chest and back indicates that there may be tumor invasion near the mediastinum on the inner side of the lung lobe.

4. Chest tightness and shortness of breath

About 10% of patients experience this as the first symptom, which is more common in central lung cancer, especially in patients with poor lung function. The main causes of dyspnea include: ① In the late stage of lung cancer, when the mediastinal lymph nodes are widely metastatic and compress the trachea, carina or main bronchi, shortness of breath or even suffocation may occur. ② When a large amount of pleural effusion compresses the lung tissue and causes severe displacement of the mediastinum, or when there is pericardial effusion, chest tightness, shortness of breath and dyspnea may also occur, but the symptoms can be relieved after fluid extraction. ③ Diffuse bronchioloalveolar carcinoma and bronchial disseminated adenocarcinoma reduce the respiratory area and gas diffusion dysfunction, leading to severe ventilation/perfusion ratio imbalance, causing dyspnea to gradually worsen, often accompanied by cyanosis. ④ Others: including obstructive pneumonia. Atelectasis, lymphangitic lung cancer, tumor microembolism, upper airway obstruction, spontaneous pneumothorax and combined chronic lung diseases such as COpD.

5. Hoarseness

5% to 18% of lung cancer patients present with hoarseness as the first complaint, usually accompanied by cough. Hoarseness generally indicates direct mediastinal invasion or enlarged lymph nodes involving the ipsilateral recurrent laryngeal nerve, resulting in left vocal cord paralysis. Vocal cord paralysis can also cause varying degrees of upper airway obstruction.

(II) Systemic symptoms

1. Fever

This is the first symptom in 20% to 30% of cases. There are two reasons for fever caused by lung cancer. One is inflammatory fever. When central lung cancer tumors grow, they often block the segment or bronchial opening first, causing obstructive pneumonia or atelectasis in the corresponding lobe or segment, resulting in fever, but the temperature is mostly around 38°C and rarely exceeds 39°C. Antibiotic treatment may be effective and the shadow may be absorbed, but due to poor drainage of secretions, it often recurs. About 1/3 of patients may repeatedly develop pneumonia in the same part within a short period of time. Peripheral lung cancer often causes fever in the late stage due to inflammation caused by tumor compression of adjacent lung tissue. The second is cancer fever, which is mostly caused by the absorption of tumor necrotic tissue by the body. This type of fever is ineffective with anti-inflammatory drugs, but hormones or indole drugs have a certain effect.

2. Weight loss and cachexia

In the late stage of lung cancer, due to loss of appetite caused by infection and pain, increased consumption caused by tumor growth and toxins, and increased levels of cytokines such as TNF and Leptin in the body, severe weight loss, anemia, and cachexia may occur.

(III) Extrapulmonary symptoms

Due to certain special active substances produced by lung cancer (including hormones, antigens, enzymes, etc.), patients may experience one or more extrapulmonary symptoms, which often appear before other symptoms and may disappear or appear with the growth and decline of the tumor. Pulmonary osteoarthritis is more common clinically.

1. Pulmonary osteoarthritis

Clinically, the main manifestations are tussock fingers (toes), periosteal hyperplasia at the distal end of long bones, new bone formation, swelling, pain and tenderness in the affected joints. The long bones are the tibia, humerus and metacarpal bones, and the joints are more common in large joints such as the knee, ankle and wrist. The incidence of tussock fingers and toes is about 29%, which is mainly seen in squamous cell carcinoma; the incidence of hyperplastic osteoarthritis is 1% to 10%, which is mainly seen in adenocarcinoma, and small cell carcinoma rarely has this manifestation. The exact cause is not yet fully understood, and it may be related to estrogen, growth hormone or nerve function. Surgical resection of the tumor can relieve or disappear, and it may recur when it recurs.

2. Ectopic hormone secretion syndrome associated with tumors

About 10% of patients may experience such symptoms, which may appear as the first symptom. Some other patients may have no clinical symptoms, but one or more plasma ectopic hormones may be detected to be elevated. Such symptoms are more common in small cell lung cancer.

(1) Ectopic adrenocorticotropic hormone (ACTH) secretion syndrome. The tumor secretes ACTH or adrenocorticotropic hormone-releasing factor-like active substances, which increases plasma cortisol. The clinical symptoms are similar to those of Cushing's syndrome, and may include progressive muscle weakness, peripheral edema, hypertension, diabetes, hypokalemic alkalosis, etc. It is characterized by rapid progression of the disease, severe mental disorders, and skin pigmentation, while central obesity, polycythemia, and purple striae are not obvious. This syndrome is more common in lung adenocarcinoma and small cell lung cancer.

(2) Ectopic gonadotropin syndrome is caused by the tumor's autonomous secretion of LH and HCG, which stimulates the secretion of gonadal steroids. It is often manifested as bilateral or unilateral breast development in men. It can occur in lung cancer of various cell types, with undifferentiated carcinoma and small cell carcinoma being the most common. Occasionally, abnormal penile erection can be seen, which is related to abnormal hormone secretion and may also be caused by penile vascular embolism.

(3) Ectopic parathyroid hormone syndrome is caused by tumor secretion of parathyroid hormone or an osteolytic substance (peptide). Clinically, it is characterized by hypercalcemia and hypophosphatemia, and symptoms include loss of appetite, nausea, vomiting, abdominal pain, thirst, weight loss, tachycardia, arrhythmia, irritability and mental confusion. It is more common in squamous cell carcinoma.

(4) Ectopic insulin secretion syndrome is clinically manifested by subacute hypoglycemia symptoms, such as mental confusion, hallucinations, headaches, etc. The cause may be related to the tumor consuming a large amount of glucose, secreting body fluid substances with insulin-like activity, or secreting insulin-releasing polypeptides.

(5) Carcinoid syndrome is caused by the secretion of 5-hydroxytryptamine by the tumor. It manifests as bronchospasmodic asthma, skin flushing, paroxysmal tachycardia, and watery diarrhea. It is more common in adenocarcinoma and oat cell carcinoma.

(6) Neuromuscular syndrome (Eaton-Lambert syndrome) is caused by the secretion of arrow-like substances by the tumor. It manifests as decreased voluntary muscle strength and extreme fatigue. It is more common in small cell undifferentiated carcinoma. Other symptoms include peripheral neuropathy, spinal root ganglion cell and nerve degeneration, subacute cerebellar degeneration, cortical degeneration, polymyositis, etc., which may cause pain and weakness in the extremities, dizziness, nystagmus, ataxia, difficulty walking, and dementia.

(7) Ectopic growth hormone syndrome manifests as hypertrophic osteoarthritis, which is more common in adenocarcinoma and undifferentiated carcinoma.

(8) Syndrome of inappropriate antidiuretic hormone secretion is caused by the secretion of large amounts of ADH or polypeptide substances with antidiuretic effects by cancer tissues. Its main clinical features are hyponatremia, accompanied by low osmotic pressure of serum and extracellular fluid (&270mosm=""l="">1.200) and water intoxication. It is more common in small cell lung cancer.

3. Other manifestations

(1) Skin lesions Acanthosis nigricans and dermatitis are more common in adenocarcinoma, while skin pigmentation is caused by the secretion of melanocyte stimulating hormone (MSH) by the tumor and is more common in small cell carcinoma. Other skin lesions include scleroderma and palmoplantar hyperkeratosis.

(2) Cardiovascular system: All types of lung cancer may cause abnormal coagulation mechanisms, resulting in migratory venous thrombosis, phlebitis, and non-bacterial embolic endocarditis, which may occur several months before the diagnosis of lung cancer.

(3) Hematological system symptoms include chronic anemia, purpura, erythrocytosis, and leukemoid reactions. These symptoms may be caused by reduced iron absorption, shortened life span due to erythropoiesis disorders, capillary osmotic anemia, etc. In addition, DIC may occur in lung cancers of various cell types, which may be related to the release of procoagulant factors by the tumor. Patients with squamous cell lung cancer may also have purpura.

4. Symptoms of invasion and metastasis

1. Lymph node metastasis

The most common lymph nodes are mediastinal and supraclavicular lymph nodes, which are usually on the same side as the lesion, and a few may be on the opposite side. They are usually hard, single or multiple nodules, and may sometimes be the first complaint leading to medical attention. Enlarged lymph nodes near the trachea or under the carina may compress the airway, causing chest tightness, shortness of breath, or even suffocation. Compression of the esophagus may cause dysphagia.

2. Pleural invasion and/or metastasis

The pleura is a common site of invasion and metastasis of lung cancer, including direct invasion and implant metastasis. Clinical manifestations vary depending on the presence or absence of pleural effusion and the amount of pleural effusion. In addition to direct invasion and metastasis, the causes of pleural effusion also include lymph node obstruction and associated obstructive pneumonia and atelectasis. Common symptoms include dyspnea, cough, chest tightness and chest pain, etc., or there may be no symptoms at all; physical examination can show fullness of the intercostals, widening of the intercostals, decreased breath sounds, decreased vocal fremitus, percussion sound, mediastinal shift, etc. Pleural effusion can be serous, serous bloody or bloody, most of which are exudates. Malignant pleural effusion is characterized by rapid growth and is mostly bloody. Spontaneous pneumothorax can occur in extremely rare lung cancer. Its mechanism is direct invasion of the pleura and rupture of obstructive emphysema. It is more common in squamous cell carcinoma and has a poor prognosis.

3. Superior Vena Cava Syndrome (SVCS)

Direct invasion of the tumor or metastasis of the mediastinal lymph nodes compresses the superior vena cava, or embolism in the cavity causes it to narrow or occlude, resulting in blood reflux obstruction and a series of symptoms and signs, such as headache, facial edema, cervical and chest varicose veins, increased pressure, dyspnea, cough, chest pain, and dysphagia, and often fainting or dizziness when bending over. The veins in the anterior chest and upper abdomen may be compensatory varicose, reflecting the time of superior vena cava obstruction and the anatomical location of the obstruction. The symptoms and signs of superior vena cava obstruction are related to its location. If the innominate vein on one side is blocked, the blood flow from the head, face, and neck can return to the heart through the innominate vein on the opposite side, and the clinical symptoms are mild. If the superior vena cava obstruction occurs below the entrance of the azygos vein, in addition to the above-mentioned venous dilatation, there is also abdominal venous distension, and blood flows into the inferior vena cava through this route. If the obstruction develops rapidly, cerebral edema may occur with headache, drowsiness, irritability, and changes in consciousness.

4. Kidney metastasis

About 35% of patients who died of lung cancer were found to have renal metastasis, which is also the most common metastatic site for patients who died within one month after lung cancer surgery. Most renal metastases have no clinical symptoms, but sometimes they can manifest as low back pain and renal insufficiency.

5. Digestive tract metastasis

Liver metastasis may manifest as loss of appetite, pain in the liver area, sometimes accompanied by nausea, serum γ-GT is often positive, AKp is progressively increased, and physical examination may reveal an enlarged liver with a hard and nodular feel. Small cell lung cancer is prone to pancreatic metastasis, which may cause symptoms of pancreatitis or obstructive jaundice. Lung cancer of various cell types can metastasize to the liver, gastrointestinal tract, adrenal glands, and retroperitoneal lymph nodes. Most of them are clinically asymptomatic and are often discovered during physical examination.

6. Bone metastasis

Common sites of lung cancer bone metastasis include ribs, vertebrae, ilium, femur, etc., but the ipsilateral ribs and vertebrae are more common, manifested as local pain and fixed point tenderness and percussion pain. Spinal metastasis can compress the spinal canal and cause obstruction or compression symptoms. Joint involvement can cause joint effusion, and puncture may detect cancer cells.

7. Central nervous system symptoms

(1) The incidence of brain, meningeal and spinal cord metastasis is about 10%, and the symptoms may vary depending on the site of metastasis. Common symptoms include increased intracranial pressure, such as headache, nausea, vomiting, and changes in mental status. Rare symptoms include epileptic seizures, cranial nerve involvement, hemiplegia, ataxia, aphasia, and sudden fainting. Meningeal metastasis is less common than brain metastasis and often occurs in patients with small cell lung cancer. Its symptoms are similar to those of brain metastasis.

(2) Encephalopathy and cerebellar cortical degeneration The main manifestations of encephalopathy are dementia, psychosis and organic lesions, and cerebellar cortical degeneration is manifested as acute or subacute limb dysfunction, limb movement difficulties, movement tremor, dysphonia, vertigo, etc. There are reports that the above symptoms can be alleviated after tumor resection.

8. Heart invasion and metastasis

It is not uncommon for lung cancer to affect the heart, especially central lung cancer. The tumor can invade the heart through direct spread, or spread retrogradely through the lymphatic vessels, blocking the heart's drainage lymphatic vessels and causing pericardial effusion. Those who develop slowly may be asymptomatic, or only have pain in the precordial area, under the ribs, or in the upper abdomen. Those who develop quickly may present with typical symptoms of pericardial tamponade, such as anxiety, palpitations, distended neck and facial veins, enlarged heart borders, low and distant heart sounds, hepatomegaly, ascites, etc.

9. Peripheral nervous system symptoms

When the cancer compresses or invades the cervical sympathetic nerve, it causes Horner's syndrome, which is characterized by constriction of the pupil on the affected side, ptosis, enophthalmos, and anhidrosis on the face. When the cancer compresses or invades the brachial plexus, it causes brachial plexus compression signs, which are manifested as burning radiating pain in the ipsilateral upper limb, local paresthesia, and nutritional atrophy. When the tumor invades the phrenic nerve, it may cause diaphragmatic paralysis, chest tightness, and shortness of breath. Under X-ray fluoroscopy, paradoxical movement of the diaphragm may be seen. When the tumor compresses or invades the recurrent laryngeal nerve, it may cause vocal cord paralysis and hoarseness. Tumors at the apex of the lung (superior pulmonary sulcus tumors) invade the C8 and T1 nerves, brachial plexus, sympathetic ganglia, and adjacent ribs, causing severe shoulder and arm pain, paresthesia, mild paralysis or weakness of one arm, and muscle atrophy, which is the so-called pancoast syndrome.

The treatment process for lung cancer patients is very long. We must smoke and drink less in our daily lives and cherish our lives. Because of the brevity of life, many happy families have come to an end. This is such a sad thing. We can achieve early detection and early treatment based on the above symptoms.