The clinical manifestations of lung cancer are closely related to its location, size, type, stage of development, and the presence of complications or metastases. Five to 15 percent of patients are asymptomatic when lung cancer is detected. The main symptoms include the following.
I. Symptoms caused by the primary tumor
1.Cough
It is a common early symptom. Tumor in the trachea may cause irritating dry cough or a small amount of mucus sputum. Alveolar cancer may have a large amount of mucus sputum. The tumor causes distal bronchial narrowing, and the cough is aggravated, mostly persistent and with a high-pitched metallic sound. It is a characteristic obstructive cough. When there is secondary infection, the sputum volume increases and is mucopurulent.
2.Hemoptysis
Hemoptysis is often caused by the rich vascularity of cancerous tissues. It is mostly bloody sputum or intermittent bloody sputum, which is often not easy to attract patients’ attention and delay early diagnosis. If it erodes large blood vessels, it may cause hemoptysis.
3.Shortness of breath
Due to partial obstruction of bronchus caused by tumor, about 2% of patients can cause limited wheezing sound.
4.Thoroughness and shortness of breath
Bronchial stenosis caused by tumor, especially central type lung cancer, or tumor metastasis to lymph nodes in the hilum, the enlarged lymph nodes compressing the main bronchus or rundown, or metastasis to the pleura, a large amount of pleural effusion, or metastasis to the pericardium and pericardial effusion, or glandular palsy, superior vena cava obstruction and extensive lung involvement, can affect the lung function and cause chest tightness and shortness of breath, if the original chronic obstructive pulmonary disease, or combined with If the original chronic obstructive pulmonary disease, or combined with spontaneous pneumothorax, chest tightness and shortness of breath are more serious.
5.Weight loss
Weight loss is one of the common symptoms of tumor. When the tumor develops to advanced stage, due to tumor toxin and consumption, and the loss of appetite caused by infection and pain, it can be manifested as emaciation or cachexia.
6.Fever
Generally tumor can cause fever due to necrosis. Most of the fever is due to secondary pneumonia caused by tumor, and antibiotic drug treatment is not effective.
Symptoms caused by local extension of tumor
1.Chest pain
About 30% of the tumors directly invade the pleura, ribs and chest wall, which can cause chest pain of different degrees. If the tumor is located near the pleura, it will produce irregular dull pain or hidden pain, and the pain will be aggravated when breathing and coughing. When the ribs and spine are invaded, there will be pressure pain points, but not related to breathing and coughing. If the tumor compresses the intercostal nerve, the chest pain may involve its distribution area.
2.Difficulty in breathing
If the tumor presses the large airway, inspiratory dyspnea may occur.
3.Swallowing difficulty
Cancer invading or compressing the esophagus may cause dysphagia, and it may also cause broncho-esophageal fistula and lead to lung infection.
4.Heartiness of voice
Hoarseness may occur when the cancer directly presses or metastasizes to the enlarged mediastinal lymph nodes and presses on the recurrent laryngeal nerve (mostly seen on the left side).
5.Superior vena cava obstruction syndrome
When the cancer invades the mediastinum and presses the superior vena cava, the flow of the superior vena cava is blocked, resulting in edema of the head, face, neck and upper limbs, as well as bruising and varicose veins in the anterior part of the chest, which may cause headache or dizziness or vertigo.
6.Horner syndrome
Lung cancer located in the apical part of the lung is called superior sulcus carcinoma, which can compress sympathetic nerve in the neck, causing drooping eyelid, narrow pupil and sunken eye on the side of the disease, and no or little sweating on the frontal and chest wall on the same side, and there is also burning pain mainly in the lower axilla and radiating to the inner side of the upper limb due to the compression of brachial plexus nerve by the tumor, especially at night.
Symptoms caused by distant metastasis of cancer
1.When lung cancer metastasizes to the chest and central nervous system, neurological symptoms such as headache, vomiting, vertigo, diplopia, ataxia, cerebral nerve palsy, weakness of one limb or even hemiplegia may occur. In severe cases, symptoms of intracranial hypertension may occur.
2.In case of metastasis to bones, especially ribs, vertebrae and pelvis, there is local pain and pressure pain.
3.When metastasis to liver, there may be anorexia, pain in liver area, hepatomegaly, jaundice and ascites, etc.
4.Lung cancer metastasis to lymph nodes The supraclavicular lymph node is often the site of lung cancer metastasis, which can be asymptomatic and the patient comes to the clinic for diagnosis. Typically, they are located in the anterior oblique muscle area, fixed and hard, gradually increasing in size and number, and can be fused. The size of lymph nodes does not necessarily reflect the early or late stage of the disease, and they are mostly painless; subcutaneous nodes can be palpated in case of subcutaneous metastasis.
Extra-pulmonary manifestations caused by cancer acting on other systems
They include abnormal changes of endocrine, neuromuscular, connective tissue, blood system and blood vessels, also called paraneoplastic syndrome. There are several manifestations as follows.
1. Hypertrophic pulmonary osteoarthropathy is commonly seen in lung cancer, but also in pleural limited mesothelioma and pulmonary metastases (metastases from thymus, uterus and prostate). It mostly invades the distal ends of the long bones of the upper and lower extremities and occurs with pestle-like fingers (toes) and hypertrophic osteoarthropathy. The former is characterized by rapid onset, painful finger ends, and environmental erythema around the nail bed. Both are often present at the same time, mostly in squamous carcinoma. After excision of lung cancer, the symptoms can be reduced or disappear, and tumor recurrence can appear again.
2.Secretion of gonadotropic hormone causes gynecomastia, often accompanied by hypertrophic osteoarthropathy.
3.Secretion of pro-adrenocorticotropic hormone-like substance can cause Cushing syndrome, which is manifested as muscle weakness, swelling, hypertension and increased urine sugar, etc.
4.Secretion of antidiuretic hormone causes dilutional hyponatremia, manifesting as poor appetite, nausea, vomiting, weakness, drowsiness, disorientation and other symptoms of water intoxication, called the syndrome of inappropriate secretion of antidiuretic hormone.
5, neuromuscular syndrome including cerebellar cortical degeneration, spinal cerebellar degeneration, peripheral neuropathy, myasthenia gravis and myopathy. The cause of occurrence is not clear. These symptoms are not related to the location of the tumor and the presence of metastasis. It can occur several years before the appearance of the tumor or as a symptom at the same time as the tumor; it can occur after surgical resection, or the original symptoms remain unchanged. It can occur in all types of lung cancer, but it is mostly seen in small cell undifferentiated cancer.
6.hypercalcemia Lung cancer can cause bone destruction due to metastasis or caused by xenobiotic parathyroid-like hormone. Hypercalcemia can occur simultaneously with vomiting, nausea, drowsiness, irritability, polyuria and mental disorder, and is mostly seen in squamous carcinoma. After surgical resection of lung cancer, blood calcium can return to normal, and tumor recurrence can cause high blood calcium again.
In addition, carcinoid syndrome caused by excessive secretion of 5-hydroxytryptamine can be seen in oat cell carcinoma and adenocarcinoma, which manifests as croup-like bronchospasm, paroxysmal tachycardia, watery diarrhea, and skin flushing. Extra-pulmonary manifestations such as acanthosis nigricans and dermatitis, palmoplantar hyperkeratosis, scleroderma, and embolic endocarditis, thrombocytopenic purpura, and capillary oedematous anemia may also be seen.