A 70-year-old woman with small-cell lung carcinoma (c-T4N2M0) was treated b
y six courses of combination chemotherapy (carboplatin and etoposide), Afte
r two weeks, she complained of a sense of darkness and night blindness. A W
estern blot analysis showed that the patient's serum bound with the recombi
nant 23-kDa retinal cancer-associated retinopathy (CAR) antigen at 1:1,000
dilution. Her visual acuity became so poor that she could only recognise a
hand motion at 50 cm despite treatment with corticosteroids and combination
chemotherapy. The patient was diagnosed as having a rare type of CAR becau
se CAR is usually found before the diagnosis of primary cancer.