Pleural Cancer

Pleural cancer occurs outside the lung in the chest or pleural cavity and along the pleural lining, the membrane that surrounds the lungs and covers the inside of the chest cavity. Cancer that occurs in the pleural cavity has most often spread (metastasized) to the pleura from somewhere else in the body. For this reason, the disease is sometimes referred to as unknown primary pleural cancer. It has most commonly spread to the pleural space from the lung but may come from the breast, ovary, pancreas, colon, and other locations.

Primary pleural cancer is cancer that develops in the pleural cavity itself, such as with malignant pleural mesothelioma, but this is less common.

Determining the cancer’s origin and degree of involvement often requires special diagnostic testing and procedures.

UT Southwestern Medical Center’s experienced chest (thoracic) cancer physicians expertly diagnose and treat both primary and unknown primary pleural cancer.

Our thoracic cancer physicians work closely with UT Southwestern pathologists, who can sometimes identify the primary cancers that have spread to the pleura, enabling the most appropriate treatment.


If your doctor suspects that you have pleural cancer, he or she will conduct a physical examination and order tests to confirm the diagnosis. Further tests may be needed to help determine the cancer’s stage and precise location. In some cases, pathologists can determine the primary cancer that has spread to the pleura.

Imaging techniques used to diagnose pleural cancer might include:

Chest X-ray
Used to visualize abnormalities in the pericardium
Contrast enhanced or multidetector computed tomography (CT) scan
CT technology helps physicians visualize the location and extent of unknown primary pleural cancer.
Magnetic resonance imaging (MRI)
MRI helps physicians identify suspicious areas that could indicate unknown primary pleural cancer and learn if and how far it has spread.
Positron emission tomography (PET)
Cancer cells absorb large amounts of radioactive sugar used in this technique, and a special camera creates images of that radioactivity, enabling physicians to identify cancerous cells in the pleura.
Endoscopic ultrasonography
This technology maps sound waves to help physicians visualize pleural cancer.

Additional testing also may include a tissue sample (biopsy) of the pleural tissue to determine the presence of cancer.


Treatment options for unknown primary pleural cancer depend on the cancer’s precise location and stage, the patient’s overall health, goals, and preferences, and other factors.

UT Southwestern’s thoracic cancer specialists may consider these therapies for treating unknown primary pleural cancer:

Medical treatment (chemotherapy)
Chemotherapy drugs, taken orally or intravenously, may be used to target and kill cancer cells in the pleura. Chemotherapy also may be used in conjunction with radiation therapy (chemoradiation) to treat unknown primary pleural cancer.
Radiation therapy
Radiation therapy uses high-energy radiation, such as X-rays, to destroy cancer cells in the pleura. UT Southwestern is a recognized leader in the development and use of cancer-fighting radiation therapies. Learn more about radiation therapy for chest cancers.
Highly precise surgery to remove cancerous tissue may be used in some early-stage cases of unknown primary pleural cancer. Learn more about surgery for chest cancers.

Depending on the cause and extent of their unknown primary pleural cancer, some patients may be eligible to participate in clinical trials of new treatments for the disease.

Clinical Trials

UT Southwestern conducts clinical trials aimed at improving the care and outcomes of patients with pleural cancer. Your cancer physicians can help you determine if you are eligible to participate in a clinical trial.

Meet Our Experts

UT Southwestern’s chest cancer experts use a variety of advanced techniques and technologies to diagnose and care for patients with pleural cancer. Our multidisciplinary team includes these medical oncologists, radiation oncologists, and surgical oncologists.

Learn more about the chest cancer team.

Request an Appointment

To schedule an appointment with a specialist in unknown primary pleural cancer, request an appointment or call 214-645-8300.