"Patients with cancer frequently have neurologic, ophthalmologic, or neuro-ophthalmologic complications."
"Patients with cancer frequently have neurologic, ophthalmologic, or neuro-ophthalmologic complications. Often, such patients have received multiple different treatments, including chemotherapy, radiation therapy (RT), and bone marrow transplantation (BMT). The differential diagnosis of the presenting problem thus may be quite complex. One possibility is a direct effect of the cancer itself, either by metastasis or local spread. A remote paraneoplastic syndrome is another. Direct toxicity may occur from chemotherapy or RT. Toxicity may be a secondary effect, such as a drug-induced hemorrhage from thrombocytopenia or an infection from immunosuppression. Metabolic disturbances from multiple causes can produce systemic, neurologic, and ocular deficits, and multiple treatment modalities may be additive in causing neurologic or ophthalmologic toxicity. Finally, the possibility always exists that the new symptoms are totally unrelated to the cancer or its therapy."