Enzastaurin in Treating Patients With Persistent or Recurrent Ovarian Epithelial Cancer or Primary Peritoneal Cancer

DISEASE CHARACTERISTICS:

* Histologically confirmed ovarian epithelial or primary peritoneal carcinoma
* Recurrent or persistent disease
* Measurable disease, defined as ≥ 1 unidimensionally measurable lesion ≥ 20 mm by conventional techniques OR ≥ 10 mm by spiral CT scan

  * Must have ≥ 1 target lesion to assess response

    * Tumors within a previously irradiated field are designated as "nontarget" lesions unless progression is documented or a biopsy is obtained to confirm persistence ≥ 90 days after completion of radiotherapy
* Must have received 1 prior platinum-based chemotherapy regimen containing carboplatin, cisplatin, or another organoplatinum compound for management of primary disease

  * Initial treatment may have included high-dose therapy, consolidation therapy, or extended therapy administered after surgical or nonsurgical assessment
  * Must meet any 1 of the following criteria for platinum-based therapy:

    * Disease progression during therapy
    * Treatment-free interval after completion of treatment \< 12 months
    * Disease persistence after completion of therapy
* Ineligible for a higher priority GOG clinical trial

PATIENT CHARACTERISTICS:

* GOG performance status 0-1 (for patients who received 2 prior treatment regimens) OR 0-2 (for patients who received 1 prior treatment regimen)
* Absolute neutrophil count ≥ 1,500/mm³
* Platelet count ≥ 100,000/mm³
* Hemoglobin ≥ 9 g/dL (transfusions allowed)
* Creatinine \< 1.5 times upper limit of normal (ULN)
* Bilirubin ≤ 2 times ULN
* Alkaline phosphatase ≤ 3 times ULN (5 times ULN if liver metastases are present)
* AST and ALT ≤ 3 times ULN (5 times ULN if liver metastases are present)
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception during and for 3 months after completion of study treatment
* Able to swallow tablets
* No sensory or motor neuropathy \> grade 1
* No active infection requiring antibiotics
* No other invasive malignancies or evidence of cancer within the past 5 years except nonmelanoma skin cancer
* No serious systemic disorders that would preclude study compliance, including an abnormal ECG indicative of cardiac disease

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics
* Recovered from prior surgery, radiotherapy, or chemotherapy
* At least 1 week since prior anticancer hormonal therapy
* No more than 1 additional cytotoxic regimen for management of recurrent or persistent disease
* At least 4 weeks since other prior anticancer therapy, including immunotherapy
* At least 30 days since prior investigational drugs
* No prior enzastaurin hydrochloride
* No prior radiotherapy to \> 25% of marrow-bearing areas
* No prior noncytotoxic therapy, including bevacizumab, for recurrent or persistent disease
* No prior treatment that would preclude treatment on this protocol
* No concurrent chemotherapy, immunotherapy, or other experimental medications
* No concurrent enzyme-inducing antiepileptic drugs, including carbamazepine, phenobarbital, or phenytoin
* No other concurrent systemic anticancer therapy
* No concurrent radiotherapy, including palliative radiotherapy
* No concurrent agents that stimulate thrombopoiesis
* No concurrent amifostine or other protective reagents
* Concurrent hormone replacement therapy allowed
* Concurrent bisphosphonates allowed provided bony metastases are present