Gemcitabine and Topotecan in Treating Patients With Recurrent or Persistent Ovarian, Fallopian Tube, or Primary Peritoneal Cavity Cancer

DISEASE CHARACTERISTICS:

* Diagnosis of ovarian, fallopian tube, or primary peritoneal cavity cancer
* Recurrent or persistent platinum-refractory disease, as defined by 1 of the following:

  * Progressive disease while on a platinum compound
  * Persistent clinically measurable disease with best response as stable disease at the completion of ≥ 6 courses of therapy
  * Recurrent disease within 6 months after completion of therapy
* Measurable or evaluable disease

  * Evaluable disease, defined as CA 125 ≥ 100 U/mL (confirmed by 2 blood tests)
  * Measurable disease, defined as ≥ 1 unidimensionally measurable lesion ≥ 20 mm by conventional techniques, including palpation, plain x-ray, CT scan, or MRI, OR ≥ 10 mm by spiral CT scan

PATIENT CHARACTERISTICS:

Age

* 18 and over

Performance status

* GOG 0-3

Life expectancy

* Not specified

Hematopoietic

* Absolute neutrophil count ≥ 1,500/mm\^3
* Platelet count ≥ 100,000/mm\^3

Hepatic

* Bilirubin ≤ 1.5 times upper limit of normal (ULN)
* SGOT ≤ 2.5 times ULN
* Alkaline phosphatase ≤ 2.5 times ULN

Renal

* Creatinine ≤ 1.5 times ULN
* Creatinine clearance \> 50 mL/min

Other

* No clinically significant infection
* No other severe medical condition that would preclude study treatment
* No other malignancy within the past 5 years except nonmelanoma skin cancer or carcinoma in situ of the cervix or breast

PRIOR CONCURRENT THERAPY:

Biologic therapy

* Not specified

Chemotherapy

* See Disease Characteristics
* Prior gemcitabine or topotecan allowed provided disease is not refractory to either drug
* At least 3 weeks since prior chemotherapy and recovered

Endocrine therapy

* Not specified

Radiotherapy

* At least 3 weeks since prior radiotherapy and recovered

Surgery

* Recovered from recent prior surgery