Successful management of hyperammonemia with hemodialysis on day 2 during 5-fluorouracil treatment in a patient with gastric cancer: a case report with 5-fluorouracil metabolite analyses

Purpose Hyperammonemia is an important adverse event associated with 5-fluorouracil (5FU) from 5FU metabolite accumulation. We present a case of an advanced gastric cancer patient with chronic renal failure, who was treated with 5FU/leucovorin (LV) infusion chemotherapy (2-h infusion of LV and 5FU bolus followed by 46-h 5FU continuous infusion on day 1; repeated every 2 weeks) and developed hyperammonemia, with the aim of exploring an appropriate hemodialysis (HD) schedule to resolve its symptoms. Methods The blood concentrations of 5FU and its metabolites, α-fluoro-β-alanine (FBAL), and monofluoroacetate (FA) of a patient who had hyperammonemia from seven courses of palliative 5FU/LV therapy for gastric cancer were measured by liquid chromatography–mass spectrometry. Results On the third day of the first cycle, the patient presented with symptomatic hyperammonemia relieved by emergency HD. Thereafter, the 5FU dose was reduced; however, in cycles 2–4, the patient developed symptomatic hyperammonemia and underwent HD on day 3 for hyperammonemia management. In cycles 5–7, the timing of scheduled HD administration was changed from day 3 to day 2, preventing symptomatic hyperammonemia. The maximum ammonia and 5FU metabolite levels were significantly lower in cycles 5–7 than in cycles 2–4 (NH3 75 ± 38 vs 303 ± 119 μg/dL, FBAL 13.7 ± 2.5 vs 19.7 ± 2.0 μg/mL, FA 204.0 ± 91.6 vs 395.9 ± 12.6 ng/mL, mean ± standard deviation, all p < 0.05). After seven cycles, partial response was confirmed. Conclusion HD on day 2 instead of 3 may prevent hyperammonemia in 5FU/LV therapy.

A Case of Gingival Candidiasis with Bone Destruction on Gastric Cancer Patient Receiving Cytotoxic Chemotherapy

We herein report a case of gingival candidiasis in an advanced gastric cancer patient while receiving palliative cytotoxic chemotherapy. A 46-year-old male patient admitted to our hospital for known advanced gastric cancer with newly developed multiple liver metastases. While receiving 2nd line cytotoxic chemotherapy with 5FU, leucovorin, and paclitxel, he complained of gingival swelling accompanied by pain and whitish plaque. Due to lack of response to the conservative oral care, incisional biopsy of gingiva was done and the pathology confirmed gingival candidiasis. Although the lesion healed apparently after two-week antifungal therapy, pain as well as bony destruction remains. By presenting this case report, we intend to emphasize the immunocompromising effect of cancer while being on systemic chemotherapy.