Large cell lung cancer

Large cell lung cancer, a subtype of non-small cell lung cancer (NSCLC), is characterized by malignant cells in the lung tissues.

This type of cancer is commonly linked to smoking, secondhand tobacco exposure, or exposure to radon.

Non-small cell lung cancer accounts for 80% to 85% of all lung cancer cases and tends to spread more slowly compared to small cell lung cancer.

There are three main subtypes of large cell lung cancer:

• Squamous cell carcinoma: Also known as squamous cell carcinoma, this type is strongly linked to smoking and originates in the basal cells of the bronchial epithelium.
• Adenocarcinoma: The most common subtype, it can occur in both smokers and non-smokers. It originates from the cells that form the bronchial glands.
• Large cell carcinoma: The least common subtype, it can develop in any part of the lung.

The symptoms of large cell lung cancer vary depending on whether the tumor is confined to the lung or has spread to other organs (metastasis).

Common initial symptoms include:

• Chest pain.
• Persistent cough, sometimes with blood (hemoptysis).
• Dyspnea (difficulty breathing).
• Wheezing (whistling sounds during breathing).
• Fatigue.
• Unexplained weight loss.
• Bone pain.
• Fever.
• Dysphagia (difficulty swallowing).

In advanced cases, symptoms depend on the organs affected and may include:

• Significant weight loss.
• Severe bone and muscle pain.
• Neurological symptoms, such as headaches, syncope (loss of consciousness), seizures, weakness in extremities, or psychological changes.
• Dysphonia (hoarseness).
• In the physical examination findings may include enlarged liver (hepatomegaly).
• swollen lymph nodes larger than 1 cm and detectable masses in other parts of the body.

Lung cancer, including large cell lung cancer, is often diagnosed at an advanced stage, frequently after metastasis, as serious symptoms may not appear early.

Detecting cancer early can significantly improve life expectancy, though it is challenging. Screening for early detection in high-risk individuals has been proposed.

Chest X-rays are not effective for early detection. Low-dose computed tomography (CT) without contrast has shown promise, especially in individuals over 60 years old who smoke more than 10 pack-years.

For those presenting symptoms, the following initial tests are typically conducted:

• Computed tomography (CT) of the chest and abdomen.
• Bronchoscopy.
• A definitive diagnosis is made through a biopsy, which involves examining a tissue sample from the lung tumor or metastasis under a microscope. Biopsies can be obtained via bronchial endoscopy (bronchoscopy) or ultrasound-guided sampling through the skin and pleura.

Molecular and genetic testing of the biopsy tissue is performed to better determine treatment options.

Once large cell lung cancer is diagnosed, additional tests are conducted to classify the tumor stage and assess potential treatment-related risks. These include:

• Blood tests: Complete blood count, kidney, and liver function tests.
• Brain MRI: To check for metastasis, which is common.
• Bone scans.
• Whole-body PET scans: Positron emission tomography.
• Lung function tests: Spirometry and others.

Staging determines the extent of cancer spread within the lung, nearby areas, or throughout the body. This classification is based on detailed diagnostic studies and is essential for guiding treatment. The stages are as follows:

• Occult (hidden) Stage: Cancer cells are detected only in sputum but not visible on imaging or biopsy.
• Stage 0 (Carcinoma in Situ): Cancer is confined to a single area and is limited to a few layers of cells.
• Stage I: Cancer is localized within the lung and has not spread to lymph nodes or other areas.
• Stage II: Cancer has spread to nearby lymph nodes.
• Stage III: Cancer has spread to other structures in the chest, neck, or mediastinum:
  • Stage III-A: Often operable.
  • Stage III-B: Generally inoperable.
• Stage IV: Cancer has metastasized to other parts of the body.
• Recurrent: Cancer returns after treatment, either in the original site or elsewhere in the body.

The treatment for large cell lung cancer depends on the stage of the disease and the patient’s overall health. The main treatment options include:

• Chemotherapy: Uses medications to kill cancer cells. It can be taken orally or administered intravenously or intramuscularly. As a systemic treatment, it circulates through the bloodstream to target cancer cells throughout the body, including those outside the lungs. Preventive chemotherapy may be used to reduce the risk of a second cancer developing.
• Radiotherapy: Employs high-energy X-rays to destroy cancer cells and reduce tumor size. Can be delivered as external radiation therapy (radiation comes from a machine outside the body) or internal radiation therapy (radioactive materials are placed near cancer cells via thin plastic tubes).
• Cryosurgery: The tumor is frozen and then removed. Photodynamic therapy combines a specific type of light with a chemical agent to destroy cancer cells. Laser therapy uses a concentrated beam of light to kill cancer cells. These techniques are typically used in clinical trials or for specialized cases.

The treatment is primarily carried out with surgery or radiotherapy. In some cases, chemotherapy may be used. The prognosis and choice of treatment will depend on the stage of cancer spread, the size of the tumor, and the type of lung cancer. However, these treatments often do not cure the disease.

Patients with early-stage cancer (stages 0, I, and II) are often candidates for surgery, which may involve:

• Wedge resection: Removal of a small portion of the lung.
• Lobectomy: Removal of an entire lobe of the lung.
• Pneumonectomy: Removal of an entire lung.

If surgery is not possible due to medical reasons, local radiotherapy may be applied to target the affected area.

Patients with stage III cancer with local extension to the chest and neck can be treated with radiotherapy, surgery combined with radiotherapy, chemotherapy combined with radiotherapy, or chemotherapy alone.

In patients with cancer cell dissemination, radiotherapy is used to shrink the cancer and relieve pain. Chemotherapy may sometimes be indicated.

Occult (hidden) Large Cell Lung Cancer

• Search for the primary tumor and perform surgery, which may be curative.

Stage 0

1. Surgery, which can be curative, although there is a risk of new tumors developing.
2. Photodynamic therapy (internal use).

Stage I

1. Surgery.
2. Radiotherapy (if surgery is not possible).
3. Clinical trials exploring chemotherapy after surgery.
4. Clinical trials on preventive chemotherapy following other therapies.
5. Clinical trials investigating photodynamic therapy (internal use).

Stage II

1. Surgery to remove the tumor and affected lymph nodes.
2. Radiotherapy (for patients who cannot undergo surgery).
3. Surgery and/or radiotherapy, with or without chemotherapy.

Stage III

Stage III-A

1. Aggressive surgery.
2. Chemotherapy in combination with other treatments.
3. Surgery followed by radiotherapy.
4. Radiotherapy alone.
5. Laser therapy and/or internal radiotherapy.

Stage III-B

1. Radiotherapy alone.
2. Chemotherapy combined with radiotherapy.
3. Chemotherapy and radiotherapy followed by surgery.
4. Chemotherapy alone.
5. Cryotherapy combined with radiotherapy.

Stage IV

1. Radiotherapy to shrink tumors and relieve symptoms.
2. Chemotherapy.
3. Combination of chemotherapy and radiotherapy.
4. Laser therapy and/or internal radiotherapy.

Recurrent

1. Radiotherapy to control symptoms.
2. Chemotherapy.
3. Combination of chemotherapy and radiotherapy.
4. Surgery to remove metastases.
5. Laser therapy or internal radiotherapy.
6. Radiosurgery for select patients who cannot undergo traditional surgery.

While not all cancers can be prevented, several risk factors for lung cancer, including large cell lung cancer, can be avoided. These risk factors include:

• Smoking tobacco.
• Exposure to secondhand smoke (passive smoking).
• Exposure to radon.
• Exposure to asbestos.
• Exposure to other carcinogenic substances, such as radioactive materials, arsenic, chromium, and carbon products.

Additionally, maintaining a balanced diet and managing weight to prevent obesity can help reduce the risk of all types of cancer.