Pemetrexed Disodium/Observation in Treating Patients W/ Malignant Pleural Mesothelioma w/Out Progressive Disease After 1st Line Chemotherapy

Inclusion Criteria:

   - Histologically confirmed malignant pleural mesothelioma meeting 1 of the following
   cell types:

      - Epithelial

      - Sarcomatoid

      - Mixed type

         - Histologically documented malignant pleural mesothelioma, epithelial,
         sarcomatoid or mixed type, not amenable to surgical resection

         - Prior treatment

   - Currently receiving first-line treatment with pemetrexed + platinum; patients are to
   be registered to Cancer and Leukemia Group B (CALGB) 30901 no later than the last day
   of cycle 4 of first line therapy

   - Prior intracavitary cytotoxic or sclerosing therapy (including bleomycin) are
   acceptable; prior intrapleural cytotoxic chemotherapy will not be considered systemic
   chemotherapy

   - Prior surgical treatment is allowed

   - Prior radiation therapy is allowed

      - Non-pregnant and non-nursing; women of child bearing potential and men must agree
      to use an appropriate method of birth control throughout their participation in
      this study; appropriate methods of birth control include abstinence, oral
      contraceptives, implantable hormonal contraceptives (Norplant), or double barrier
      methods (diaphragm plus condom)

      - RANDOMIZATION ELIGIBILITY CRITERIA

      - Patients with complete response, partial response, or stable disease following 4,
      5 or 6 cycles of first-line chemotherapy with pemetrexed AND either cisplatin or
      carboplatin; a maximum of 6 cycles of chemotherapy may have been given

      - Eastern Cooperative Oncology Group (ECOG) performance status of 0-1

      - Granulocytes >= 1,500/ul

      - Platelet count >= 100,000/ul

      - Total bilirubin =< 1.5 x upper limit of normal (ULN)

      - Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase [SGOT])
      =< 2 x ULN

      - Calculated creatinine clearance >= 45 ml/min

   - Disease not amenable to surgery

   - Must be enrolled on imaging protocol CALGB-580903

   - Complete response, partial response, or stable disease after completion of 4 courses
   of first-line chemotherapy comprising pemetrexed disodium AND cisplatin or carboplatin

      - Study therapy will begin within 9 weeks following day 1 of cycle 4 of first-line
      treatment

   - No clinically significant pleural or peritoneal effusions that cannot be adequately
   managed by drainage before or during pemetrexed disodium

PATIENT CHARACTERISTICS:

   - ECOG performance status of 0-1

   - Life expectancy ≥ 12 weeks

   - Granulocytes ≥ 1,500/μL

   - Platelet count ≥ 100,000/μL

   - Total bilirubin ≤ 1.5 times upper limit of normal (ULN)

   - AST ≤ 2 times ULN

   - Creatinine clearance ≥ 45 mL/min

   - Not pregnant or nursing

   - Negative pregnancy test

   - Fertile patients must use effective contraception

   - No psychiatric illness that would prevent the patient from giving informed consent

   - No second malignancy except non-melanoma skin cancer or carcinoma in situ of the
   cervix unless curatively treated with no evidence of active disease for ≥ 5 years

   - No medical conditions that, in the opinion of the treating physician, would make study
   treatment unreasonably hazardous for the patient including, but not limited to, the
   following:

      - Ongoing or active infection such as HIV positivity

      - Inability to take oral medications

      - Psychiatric illness/social situations that would limit compliance with study
      requirements

PRIOR CONCURRENT THERAPY:

   - See Disease Characteristics

   - Prior intracavitary cytotoxic or sclerosing therapy (including bleomycin) allowed

      - Prior intrapleural cytotoxic chemotherapy not considered systemic chemotherapy

   - Prior surgery allowed

   - Prior radiotherapy allowed

      - No concurrent palliative radiotherapy

   - No concurrent hormones or other chemotherapeutic agents except for the following:

      - Steroids for adrenal failure

      - Hormones for nondisease-related conditions (e.g., insulin for diabetes)

      - Intermittent use of dexamethasone as an antiemetic or premedication for
      pemetrexed disodium