Adenocarcinoma of the lung

A type of non-small cell lung cancer

Pulmonary adenocarcinoma
Synonyms	N/A
Pronounce	/ˌæd.ɪ.noʊˌkɑːr.sɪˈnoʊ.mə/
Field	N/A
Symptoms	Cough, hemoptysis, shortness of breath, chest pain, weight loss, fatigue
Complications	Metastasis (especially to brain, liver, bones), pleural effusion, respiratory failure
Onset	Typically adults, especially ages 40+
Duration	Chronic, progressive without treatment
Types	Lepidic, acinar, papillary, micropapillary, solid
Causes	Smoking, environmental exposures (e.g., radon, asbestos), genetic mutations (e.g., EGFR, KRAS)
Risks	Smoking history, exposure to carcinogens, family history of lung cancer
Diagnosis	Chest X-ray, CT scan, biopsy, histopathology, molecular testing
Differential diagnosis	Squamous cell carcinoma, small cell lung carcinoma, metastatic carcinoma
Prevention	Smoking cessation, reducing exposure to lung carcinogens
Treatment	Surgical resection, chemotherapy, radiotherapy, immunotherapy, targeted therapy
Medication	EGFR inhibitors (e.g., erlotinib), ALK inhibitors, PD-1/PD-L1 checkpoint inhibitors
Prognosis	Variable; generally poor in late stages. 5-year survival rate ~20%
Frequency	Most common type of non-small cell lung cancer; increasing incidence worldwide
Deaths	Leading cause of cancer-related death globally

CT scan- adenocarcinoma of the left lung

Histopathology of lepidic predominant adenocarcinoma.

Adenocarcinoma of the lung is a type of lung cancer that originates in the glandular cells of the lung. It is the most common form of non-small cell lung cancer (NSCLC) and is characterized by its glandular differentiation and mucin production.

Pathophysiology

Adenocarcinoma of the lung arises from the epithelial cells that line the alveoli and the bronchioles. These cells undergo genetic mutations that lead to uncontrolled cell growth and tumor formation. The mutations often involve genes such as EGFR, KRAS, and ALK, which are critical in cell signaling pathways that regulate cell proliferation and survival.

Clinical Presentation

Patients with adenocarcinoma of the lung may present with a variety of symptoms, including persistent cough, hemoptysis (coughing up blood), dyspnea (shortness of breath), and chest pain. In some cases, the cancer may be asymptomatic and discovered incidentally on imaging studies performed for other reasons.

Diagnosis

The diagnosis of adenocarcinoma of the lung typically involves imaging studies such as chest X-ray and CT scan to identify the presence of a tumor. A definitive diagnosis is made through a biopsy, where a sample of the tumor tissue is examined histologically. Immunohistochemical staining and molecular testing are often performed to identify specific genetic mutations that may guide treatment.

Staging

Staging of lung adenocarcinoma is based on the TNM classification system, which assesses the size and extent of the primary tumor (T), the involvement of regional lymph nodes (N), and the presence of distant metastasis (M). Staging helps determine the prognosis and guides treatment decisions.

Treatment

Treatment options for adenocarcinoma of the lung depend on the stage of the disease and the presence of specific genetic mutations. Early-stage disease may be treated with surgical resection, while advanced stages may require a combination of chemotherapy, radiation therapy, and targeted therapies. Targeted therapies, such as tyrosine kinase inhibitors, are used in patients with specific genetic mutations like EGFR or ALK.

Prognosis

The prognosis for patients with adenocarcinoma of the lung varies based on the stage at diagnosis and the presence of specific genetic mutations. Early-stage disease has a better prognosis, while advanced-stage disease is associated with a poorer outcome. The development of targeted therapies has improved survival rates for patients with certain genetic mutations.

Prevention

Preventive measures for adenocarcinoma of the lung include smoking cessation, as smoking is a major risk factor for lung cancer. Avoiding exposure to environmental carcinogens, such as asbestos and radon, can also reduce the risk of developing lung cancer.

Related pages

• Lung cancer
• Non-small cell lung cancer
• EGFR
• KRAS
• ALK