Hypocalcemia associated with 5-fluorouracil and low dose leucovorin in patients with advanced colorectal or gastric carcinomas.
BACKGROUND
The biochemical modulation of 5-fluorouracil (5-FU) by leucovorin (LV) has demonstrated significantly increased response rates in comparison with the use of 5-FU alone in patients with advanced colorectal carcinoma. However, the higher response rate of LV/5-FU may occur at the expense of increased toxicity and side effects such as diarrhea, myelosuppression, and mucositis. During chemotherapy, a high incidence of hypocalcemia associated with this chemotherapy regimen was noted. This study was therefore aimed at assessing the side effects of chemotherapy using low dose LV/5-FU on calcium metabolism.


METHODS
Twenty-five patients with advanced gastric or colorectal carcinoma were treated with chemotherapy comprised of low dose LV administered at 20 mg/m2/ day by intravenous bolus, followed by 1-hour intravenous infusion of 5-FU at 425-600 mg/m2/day for 5 consecutive days every 28 days.


RESULTS
The toxic effects were generally mild, and included diarrhea, mucositis, leukopenia, and nausea/vomiting. Fifteen patients (65%) experienced hypocalcemia. The plasma 1,25-(OH)2D3 levels were significantly reduced on Day 5 due to the chemotherapy.


CONCLUSIONS
The toxic effects of the regimen were generally mild. However, a high percentage of hypocalcemia occurred with the combination of LV/5-FU. It is therefore necessary to examine carefully the serum calcium levels of patients when using this chemotherapeutic modality.
Kido
Y
Y
Department of Surgery II, Kyushu University, Fukuoka, Japan.
Okamura
T
T
Tomikawa
M
M
Yamamoto
M
M
Shiraishi
M
M
Okada
Y
Y
Kimura
T
T
Sugimachi
K
K
D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects* / Q000627:therapeutic use; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000378:metabolism*; D015179:Colorectal Neoplasms / Q000188:drug therapy*; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D006996:Hypocalcemia / Q000139:chemically induced*; D002955:Leucovorin / Q000008:administration & dosage / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D013274:Stomach Neoplasms / Q000188:drug therapy*
D010281:Parathyroid Hormone; D002117:Calcitriol; D002955:Leucovorin; D002118:Calcium; D005472:Fluorouracil