Flavopiridol in Treating Patients With Chronic Lymphocytic Leukemia or Prolymphocytic Leukemia

Inclusion Criteria:

* Histologically confirmed B-cell chronic lymphocytic leukemia (CLL) or prolymphocytic leukemia (PLL) arising from CLL

  * No de novo PLL
  * Lymphocyte count \> 5,000/mm\^3 at some point since initial diagnosis of CLL
  * B-cells co-expressing CD5 AND CD19 or CD20
  * If no dim serum immunoglobulin or CD23 expression on leukemia cells, must be examined for cyclin D1 overexpression OR t(11;14) to rule out mantle cell lymphoma
* Requiring therapy, defined by any of the following:

  * Massive or progressive splenomegaly and/or lymphadenopathy
  * Anemia (hemoglobin \< 11 g/dL) OR thrombocytopenia (platelet count \< 100,000/mm\^3)
  * Weight loss \> 10% within the past 6 months
  * Grade 2 or 3 fatigue
  * Fevers \> 100.5°C or night sweats for \> 2 weeks with no evidence of infection
  * Progressive lymphocytosis with an increase of \> 50% over a 2-month period OR an anticipated doubling time \< 6 months
* Received ≥ 1 prior chemotherapy regimen that included fludarabine or nucleoside equivalent OR alternative therapy if contraindication to fludarabine exists (i.e., autoimmune hemolytic anemia)
* Performance status - ECOG 0-2
* More than 2 years
* See Disease Characteristics
* Baseline cytopenias allowed
* WBC ≤ 200,000/mm\^3
* Bilirubin ≤ 1.5 times upper limit of normal (ULN) (unless due to Gilbert's disease, hemolysis, or disease infiltration of the liver)
* AST ≤ 2 times ULN (unless due to hemolysis or disease infiltration of the liver)
* Creatinine ≤ 2.0 mg/dL
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* No other malignancy that would limit life expectancy
* See Disease Characteristics
* No other concurrent chemotherapy
* No concurrent chronic corticosteroids or corticosteroids as antiemetics
* No concurrent hormonal therapy except steroids for new adrenal failure or hormones for nondisease-related conditions (e.g., insulin for diabetes)
* No concurrent radiotherapy