I n t r o d u c t i o n5-FU is an anti-metabolite and anti-neoplastic agent that has been used to treat a variety of cancers such as carcinoma of the breast, pancreas, colon, rectum and stomach (1). 5-FU is metabolized inside the cells to 5-fluoro-2-deoxyuridine-5-phosphate, and this metabolite inhibits thymidylate synthase. The common side effects of 5-FU are related to its effects on the bone marrow and the gastrointestinal epithelium. The symptoms include bone marrow suppression and such gastrointestinal toxicities as nausea, vomiting, diarrhea and stomatitis. Although 5-FU induced neurotoxicity is rare, the administration of 5-FU can cause both acute and delayed neurotoxicity.We report here on a patient who developed acute neurotoxicity and hyperammonemia after systemic chemotherapy with a continuous infusion of 5-FU and cisplatin.
C a s e R e p o r tA 38-year-old female underwent curative radical total gastrectomy for her stage IIIB (T3N2M0) advanced gastric cancer followed by adjuvant chemotherapy that consisted of 5-FU (1,000 mg/m 2 , i.v. on days 1 to 5) and cisplatin (60 mg/m 2 , i.v. on day 1) in 3 week cycles. The patient complained of severe emesis during chemotherapy. Fourteen days after completion of her first cycle of chemotherapy, she visited the hospital because of her weakness, anorexia, oral mucositis and diarrhea. Her blood pressure was 100/60 mmHg, the respiratory rate was 20/min, the heart rate was 94 beats/min and her body temperature was 36. Patients with reduced dihydropyrimidine dehydrogenase (DPD) activity are at risk for experiencing serious adverse effects following 5-fluorouracil (5-FU) based chemotherapy. Neurotoxicity is considered an extremely rare side effect of 5-FU. We report here on an unusual case of 5-FU induced encephalopathy. A 38-year-old woman with advanced gastric carcinoma was treated with adjuvant chemotherapy that consisted of infused 5-FU (1,000 mg/m 2 ) for 5 days and cisplatin (60 mg/m 2 ) on day 1 following total gastrectomy. Nineteen days after starting chemotherapy, the patient displayed a sudden onset of slurred speech, confusion, cognitive disturbances and paranoia. A magnetic resonance image (MRI) of the brain showed no structural abnormalities, and the other laboratory tests provided no explanations for her symptoms, other than a slightly elevated ammonia level. The patient was treated with a lactulose retention enema and thiamine infusion, the 5-FU was halted and her symptoms then recovered after 7 days.