Can cancer be visualized on a chest X-ray (X-ray)

From the Guidelines

Cancer can sometimes be visible on a chest X-ray, but this method has significant limitations for cancer detection, and more sensitive imaging techniques like CT scans are generally recommended for accurate diagnosis. Chest X-rays may reveal suspicious masses, nodules, or areas of abnormal density that could indicate lung cancer or metastases from other cancers 1. However, chest X-rays often miss small tumors and cannot reliably distinguish between cancerous and non-cancerous conditions. Many lung cancers are not detected until they are relatively large, typically at least 1 cm in diameter. For this reason, chest X-rays are not recommended as a screening tool for lung cancer in high-risk individuals, as stated in the NCCN guidelines for lung cancer screening, version 1.2025 1.

Some key points to consider when evaluating the usefulness of chest X-rays for cancer detection include:

• Chest X-rays may be useful as an initial staging investigation for soft-tissue sarcomas, but CT scans are generally preferred for detecting pulmonary metastases 1.
• The NCCN guidelines recommend using low-dose computed tomography (LDCT) of the chest to screen select patients who are at high risk for lung cancer, rather than chest X-ray 1.
• If a chest X-ray shows an abnormality that might be cancer, additional testing such as CT scans, PET scans, or tissue biopsy is usually required to confirm the diagnosis 1.
• Early-stage cancers are particularly difficult to identify on chest X-rays, which is why patients with risk factors or symptoms concerning for cancer may need more advanced imaging despite normal X-ray findings 1.

In terms of specific recommendations, the most recent and highest quality study suggests that chest X-rays are not recommended for lung cancer screening, and CT scans should be used instead 1. This is because CT scans can detect much smaller nodules and provide more detailed information about the characteristics of suspicious findings. Therefore, if cancer is suspected, a CT scan should be performed to confirm the diagnosis and guide treatment.

From the Research

Detection of Cancer on Chest X-ray

• Chest radiography has limitations in accurately detecting early lung cancer 2
• The main imaging modality for the staging of lung cancer is computed tomography (CT), supplemented by positron emission tomography (PET) 2, 3
• Imaging plays an important role in the detection, diagnosis, and staging of lung cancer, as well as in assessing response to therapy and monitoring for tumor recurrence after treatment 3

Alternatives to Chest X-ray for Cancer Detection

• Positron emission tomography (PET) has established clinical utility and cost-effectiveness in characterization of solitary pulmonary nodules and preoperative staging of carcinoma of the lung 4
• PET-CT plus cranial imaging can correctly upstage cancer in more patients with non-small cell lung cancer (NSCLC) than conventional staging plus cranial imaging 5
• PET-CT alters the stage in approximately one-third of patients compared to anatomical imaging alone, and is increasingly used to assess early metabolic response to treatment 6

Limitations of Chest X-ray

• Chest radiography is limited in detecting early lung cancer, and is not the primary imaging modality for staging lung cancer 2, 3
• While chest X-ray can detect some lung cancers, it is not sensitive enough to detect all cases, and may not provide accurate information on the extent of the disease 2, 3