A case of colon cancer recurrence with P-glycoprotein treated by methotrexate, fluorouracil, and leucovorin

A 68 year-old female underwent right hemicolectomy for an advanced cecum ca ncer and had been well without any evidence of recurrence for a year after surgery. Despite post-operative treatment with oral Tegafur (400mg/m(2)/day ), CEA level increased gradually beginning 15 months after surgery. Sequent ial chemotherapy with methotrexate (MTX) and 5-Fluorouracil (5-FU), followe d by leucovorin rescue (MFL) was started on an outpatient basis, and has be en continued every 4 weeks since then. It consisted of MTX (100mg/m(2)) and 5-FU (600mg/m(2)) started 24 hours after MTX, followed by oral leucovorin (15mg/body) started 30 hours after MTX 6 times at intervals of 6 hours. CEA level declined initially, but increased slowly for 3 years on MFL, althoug h no evidence of recurrence was detected by imaging studies with computed t omography, ultrasound, and scintigram. Four years after surgery, a tumor re currence developed in the abdominal wall. The patient underwent resection o f the tumor, resulting in a decline of the CEA level. She has been alive an d well for 5 years on MFL after the primary surgery. Both the original tumo r and recurrent tumor showed immunoreactivity for P-glycoprotein. The prese nt case demonstrates the feasibility of using MFL on an outpatient basis, a nd its potential to suppress the colon cancer growth with P-glycoprotein ex pression.