Gemcitabine and Pemetrexed Disodium in Treating Patients With Advanced Mycosis Fungoides or Sézary Syndrome

DISEASE CHARACTERISTICS: * Histologically confirmed\* mycosis fungoides or Sézary syndrome * Stage IB-IVB disease NOTE: \*Pathology report must read diagnostic or consistent with mycosis fungoides/Sézary syndrome * Failed ≥ 1 prior systemic treatment * Measurable disease * At least 1 indicator lesion must be designated prior to study entry PATIENT CHARACTERISTICS: * ECOG performance status 0-2 * Life expectancy ≥ 6 months * Creatinine ≤ 2.0 mg/dL * Creatinine clearance ≥ 45 mL/min * Bilirubin ≤ 2.2 mg/dL * AST and ALT ≤ 2 times upper limit of normal * WBC ≥ 3,000/mm³ * Absolute neutrophil count ≥ 1,500/mm³ * Platelet count ≥ 100,000/mm³ * No acute infection requiring systemic treatment * No history of severe hypersensitivity reaction to the study drugs or to any other ingredient used in their formulation * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: * See Disease Characteristics * At least 4 weeks since prior topical therapy, systemic chemotherapy, or biological therapy * No acetylsalicylic acid or other nonsteroidal anti-inflammatory drugs (NSAIDs) for 2 days before and for 2 days after pemetrexed disodium infusion (5 days before and for 2 days after pemetrexed disodium infusion for patients taking NSAIDs with a long half-life \[e.g., naproxen, refocoxib, or celecoxib\]) * No concurrent topical agents except emollients * No other concurrent topical or systemic anticancer therapies …