Lung Cancer Metastasis to the Eye
Lung cancer is the leading cause of death among cancer patients (both men and women) around the world. Of all the different cellular types of lung cancers, adenocarcinomas are the most common, occurring in 30 to 40 percent of cases.
Adenocarcinoma of the lungs are tumors that grow in the outer part of the lungs and are commonly found even in non-smokers. These tumors typically affect people younger than 45 years old and are the most common type among Asians. Individuals with advanced adenocarcinoma have a poor five-year survival rate, especially when metastases have taken place.
In advanced cases of lung cancer, tumor cells may break away and are carried by the blood to different parts of the body. The liver, brain, and bones are the most commonly involved organs outside the chest.
Quite uncommonly, lung cancer cells may also be transported to the orbit of the eye, which is the bony socket that holds the eye in place. ‘Orbit’ may also refer to the contents such as the eye, muscles, nerves and blood vessels. Orbital metastatic adenocarcinoma of the lung is an uncommon presentation of lung cancer.
Cancer metastasis from other organs is the most common cause of eye malignancies. In men, the lungs are the most common source of metastases and the rest are from unknown primary sources. In women, breast cancer is the most common source, while lung cancer is next as the primary source.
In the case of lung cancer, the disease is usually diagnosed from a metastasis, so that an eye tumor may be the initial presenting sign. Eye symptoms from the tumor will lead to the diagnosis of the primary source of cancer if not yet known.
Orbital metastasis usually occurs in the seventh decade of life, although in children, it may come from other sources such as Wilm’s tumors or neuroblastomas.
Symptoms of Orbital Tumors
Orbital tumors from lung cancer produce symptoms related to tumor enlargement and pushing of orbital contents. These symptoms include:
- Blurred vision
- Eye pain
- Eye displacement, dislocation, or bulging (proptosis)
- Cross-eyes or diplopia
- Partially diminished area of vision or scotomata
- Eye movement disorder or paralysis
- Blindness due to retinal detachment
Diagnosis and Management
Differential diagnoses or other causes that may produce these symptoms aside from metastatic tumors are other kinds of benign tumors, hemangiomas or vascular malformations, cysts and other soft tissue masses.
Diagnosis may be established through history, physical and ophthalmologic examination and laboratory examinations. Radiologic imaging of the tumor, CT scan and magnetic resonance imaging (MRI) are the best ways to evaluate the size, location and extent of the metastatic lesions. Confirmation of the diagnosis is done through fine needle aspiration biopsy, which reveals the type and source of cancer cells such as in adenocarcinoma of the lungs.
Generally, orbital metastasis is a sign of the pervasive spread of the disease and is an ominous sign. Management depends on the patient’s general health and advancement of the disease. Treatment of orbital metastatic adenocarcinoma of the lung may include observation, enucleation (eyeball removal), chemotherapy and radiotherapy. Prognosis for inoperable lung cancer is usually poor.
J Thorac Cardiovasc Surg, “Metastatic Pattern in Adenocarcinoma of the Lung”, https://jtcs.ctsnetjournals.org/cgi/content/abstract/110/4/1130
Eye Rounds, “Metastatic Choroidal Lesion”, https://webeye.ophth.uiowa.edu/eyeforum/cases/35-MetastaticLungCA.htm