Pemetrexed Disodium in Treating Patients With Recurrent or Persistent Low-Risk Gestational Trophoblastic Tumor After a Molar Pregnancy

OBJECTIVES:

- Determine the activity of pemetrexed disodium as salvage therapy in patients with
persistent or recurrent low-risk post-molar gestational trophoblastic tumor that failed
prior dactinomycin or methotrexate.

- Determine the toxicity of this drug in these patients.

OUTLINE: This is a multicenter study.

Patients receive pemetrexed disodium IV over 10 minutes on day 1. Courses repeat every 21
days in the absence of unacceptable toxicity or disease progression or until tumor marker
levels (human chorionic gonadotropin [hCG]) become normal. Patients receive 2 additional
courses beyond the attainment of a normal hCG.

Beginning 7 days before and continuing until 3 weeks after the last dose of pemetrexed
disodium, patients also receive oral folic acid daily and cyanocobalamin (vitamin B_12)
intramuscularly every 9 weeks.

Patients are followed every 2 weeks for 2 months and then monthly for 10 months.

PROJECTED ACCRUAL: Approximately 17-55 patients will be accrued for this study within 20-50
months.

DISEASE CHARACTERISTICS:

- Diagnosis of low-risk post-molar gestational trophoblastic tumor, defined as 1 of the
following:

- Increasing human chorionic gonadotropin (hCG) levels on ≥ 3 consecutive
measurements taken over ≥ a 2-week period

- Less than 10% decrease of hCG levels on 4 measurements taken over ≥ a 3-week
period

- Persistent or recurrent disease

- Histologically confirmed complete or partial mole on initial evacuation

- Prior pregnancy ≤ 12 months ago

- No histologically confirmed choriocarcinoma or placental site trophoblastic tumor on
initial evacuation

- Failed only 1 prior dactinomycin or methotrexate therapy (with or without leucovorin
calcium)

- WHO score 2-6

- No evidence of metastatic disease, except to the lung or vagina, on physical exam,
chemistry, chest X-ray, and ultrasound

- No liver, spleen, brain, kidney, or gastrointestinal tract metastases

- No more than 8 metastatic lesions

PATIENT CHARACTERISTICS:

Age

- Any age

Performance status

- GOG 0-1

Life expectancy

- Not specified

Hematopoietic

- Absolute neutrophil count ≥ 1,500/mm^3

- Platelet count ≥ 100,000/mm^3

- Granulocyte count ≥ 1,500/mm^3

Hepatic

- Bilirubin ≤ 1.5 times upper limit of normal (ULN)

- SGOT ≤ 3 times ULN

- Alkaline phosphatase ≤ 3 times ULN

Renal

- Creatinine ≤ 1.5 mg/dL

- Creatinine clearance ≥ 45 mL/min

Other

- Not pregnant or nursing

- Fertile patients must use effective contraception during and for 3 months after study
participation

- No significant infection

- No other invasive malignancy within the past 5 years except nonmelanoma skin cancer

PRIOR CONCURRENT THERAPY:

Biologic therapy

- No concurrent prophylactic filgrastim (G-CSF) unless for recurrent neutropenic
complications

- No concurrent prophylactic thrombopoietic agents unless for recurrent grade 4
thrombocytopenia

Chemotherapy

- See Disease Characteristics

- At least 7 days since prior dactinomycin or methotrexate (with or without leucovorin
calcium) and recovered

- No prior pemetrexed disodium

- No other prior chemotherapy

Endocrine therapy

- Not specified

Radiotherapy

- At least 14 days since prior radiotherapy and recovered

- No prior radiotherapy to ≥ 25% of the bone marrow

Surgery

- Recovered from prior surgery

Other

- No nonsteroidal anti-inflammatory drugs or salicylates for 2 days (or 5 days for drugs
with a long half-life) before, during, and for 2 days after pemetrexed disodium
administration

- Concurrent low-dose aspirin (≤ 325 mg/day) allowed