title: Corneal limbal stem cell deficiency associated with the anticancer drug S-1.
abstract: OBJECTIVE
  An oral antineoplastic drug, S-1, is known to be more effective with less toxicity and fewer gastrointestinal side effects than the conventional intravenous 5-fluorouracil. We report a case of limbal stem cell deficiency that occurred in a patient receiving chemotherapy using S-1 alone for gastric cancer.
  
  
  METHODS
  A 65-year-old woman with symptoms of grittiness and epiphora in both eyes for several months was referred to the ophthalmology clinic. She had been receiving S-1 orally after total gastrectomy for advanced gastric cancer. Slit lamp examination revealed an irregular hazy corneal epithelium in both eyes that extended to the center of the cornea overlying the pupil and showed late staining with fluorescein dye. Palisades of Vogt at the superior limbus were absent in both eyes. Best-corrected distance vision was 20/50 in both eyes with all other structures of the anterior and posterior segment unremarkable including a patent lacrimal drainage system. There was no change in the corneal lesions of either eye despite 3 months of topical therapy. The lesions did resolve in 4 months after discontinuation of S-1 therapy owing to acute renal failure.
  
  
  CONCLUSIONS
  Early detection of this adverse reaction before significant visual loss through regular follow-up appears to be important in patients receiving S-1 therapy.
authors.affiliation: *MD †MD, PhD Department of Ophthalmology, Haeundae Paik Hospital, Busan, South Korea (both authors); and Department of Ophthalmology, Inje University College of Medicine, Busan, South Korea (both authors).
authors.forename: Kyeong Hwan
authors.initials: KH
authors.lastname: Kim
authors.forename: Wan Soo
authors.initials: WS
authors.lastname: Kim
mesh_terms: D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000009:adverse effects*; D003316:Corneal Diseases / Q000139:chemically induced* / Q000175:diagnosis; D004338:Drug Combinations; D019573:Epithelium, Corneal / Q000187:drug effects* / Q000473:pathology; D005260:Female; D005743:Gastrectomy; D006801:Humans; D016850:Limbus Corneae / Q000187:drug effects* / Q000473:pathology; D010094:Oxonic Acid / Q000009:adverse effects*; D013234:Stem Cells / Q000187:drug effects* / Q000473:pathology; D013274:Stomach Neoplasms / Q000188:drug therapy / Q000601:surgery; D005641:Tegafur / Q000009:adverse effects*; D014792:Visual Acuity
chemical_list: D000964:Antimetabolites, Antineoplastic; D004338:Drug Combinations; C079198:S 1 (combination); D005641:Tegafur; D010094:Oxonic Acid