Pralatrexate and Fluorouracil in Treating Patients With Recurrent Solid Tumors

Inclusion Criteria:

* Cancer patients who have failed standard therapy for their disease or for whom no such therapy is available are eligible, for which 5-fluoropyrimdines, including 5-FU, or inhibitors of DHFR (dihydrofolate reductase), including pralatrexate, have the potential for therapeutic benefit
* Objectively measurable disease is preferred, but not required
* Performance status of 0-2 (Eastern Cooperative Oncology Group \[ECOG\])
* Prior treatment:
* The patient should have recovered from the toxicities associated with prior chemotherapy (at least 3 weeks from prior therapy)
* At least two or more weeks should have elapsed since any radiotherapy, and the patient should have recovered from the toxicity associated with such therapy
* If a recent surgical procedure has been performed, the patient should have recovered from the surgery prior to entering this trial
* Absolute granulocyte count of 1500 per mcL or greater
* Platelet count of 100,000 per mcL or greater
* Serum bilirubin less than 1.5 times the upper limits of the institutional normal
* Serum creatinine less than the upper limits of normal
* The patient must willingly give signed informed consent

Exclusion Criteria:

* Pregnant women and nursing mothers are ineligible; eligible patients of reproductive potential should use adequate contraception if sexually active
* Serious concurrent medical illness which would jeopardize the ability of the patient to receive the chemotherapy program outlined in this protocol with reasonable safety
* Patients with active infections requiring intravenous antibiotic therapy are not eligible until the infection has resolved
* Patients who are human immunodeficiency virus (HIV) antibody positive and are receiving highly active antiretroviral therapy (HAART) are ineligible
* Concomitant administration of nonsteroidal anti-inflammatory drugs (NSAIDs) and trimethoprim/sulfamethoxazole will not be allowed