Inclusion Criteria:

- Diagnosis of acute myeloid leukemia by World Health Organization (WHO) criteria
(except acute promyelocytic leukemia), or myelodysplastic syndrome, RAEB-2 by WHO
classification or advanced myeloproliferative neoplasm with >= 10% blasts in the bone
marrow or peripheral blood, including chronic myelomonocytic leukemia (CMML)-2 by WHO
classification

- Eastern Cooperative Oncology Group (ECOG) Performance Status 0 - 2

- Serum creatinine =< 1.0 mg/dL; if serum creatinine > 1.0 mg/dL, then the estimated
glomerular filtration rate (GFR) must be > 60 mL/min/1.73 m^2 as calculated by the
Modification of Diet in Renal Disease equation

- Serum bilirubin =< 1.5 x upper limit of normal (ULN) unless elevation is thought to
be due to Gilbert's syndrome, hemolysis, or hepatic infiltration by the hematologic
malignancy

- Aspartate transferase (AST)/alanine transferase (ALT) =< 2.5 x ULN unless elevation
is thought to be due to hepatic infiltration by the hematologic malignancy

- Alkaline phosphatase =< 2.5 x ULN

- Capable of understanding the investigational nature, potential risks and benefits of
the study, and able to provide valid informed consent

- Female patients of childbearing potential must have a negative serum pregnancy test
within 2 weeks prior to enrollment

- Male and female patients must use an effective contraceptive method during the study
and for a minimum of 90 days after study treatment

Exclusion Criteria:

- Current concomitant chemotherapy, radiation therapy, or immunotherapy other than as
specified in the protocol with the exception of intrathecal chemotherapy administered
on days that are not concurrent with clofarabine and cytarabine

- No prior induction chemotherapy for AML; treatment with hydroxyurea is permitted;
treatment with imides or hypomethylating agents for preceding hematological disorders
is permitted

- Have any other severe concurrent disease, or have a history of serious organ
dysfunction or disease involving the heart, kidney, liver, or other organ system that
may place the patient at undue risk to undergo treatment

- Patients with significant organ compromise due to systemic fungal, bacterial, viral,
or other infection

- Pregnant or lactating patients

- Any significant concurrent illness, condition, or psychiatric disorder that would
compromise patient safety or compliance, interfere with consent, study participation,
follow up, or interpretation of study results

- Have had a diagnosis of another malignancy, unless the patient has been disease-free
for at least 3 years following the completion of curative intent therapy including
the following:

- Patients with treated non-melanoma skin cancer, in situ carcinoma, or cervical
intraepithelial neoplasia, regardless of the disease-free duration, are eligible
for this study if definitive treatment for the condition has been completed

- Patients with organ-confined prostate cancer with no evidence of recurrent or
progressive disease based on prostate-specific antigen (PSA) values are also
eligible for this study if hormonal therapy has been initiated or a radical
prostatectomy has been performed

- Prior allogeneic stem cell transplant