Doxorubicin With or Without Sildenafil, With Analysis of Cardiac Markers

Inclusion Criteria:

• Patients with any malignancy that is deemed appropriate for treatment with achemotherapy regimen incorporating a < 3-hour infusion of doxorubicin >= 40mg/m^2/dose not more frequently than weekly; single agent doxorubicin and combinationchemotherapy are allowed; the duration of treatment and the cumulative dose ofdoxorubicin are determined by the chemotherapy regimen chosen for treatment of eachindividual's disease and up to the discretion of the treating provider; priordoxorubicin-based regimen(s) allowed, unless the most recent prior doxorubicin-basedregimen resulted in documented refractory disease

• At least 30 days since last doxorubicin before initiation of current doxorubicin-basedregimen

• Performance status Eastern Cooperative Oncology Group (ECOG) equal to or less than 2

• Life-expectancy > 1 year

• Women of childbearing potential and men must agree to use a medically accepted form ofbirth control for the duration of study and for a minimum of 6 months after the lastdose of doxorubicin

• Ability to understand and the willingness to sign a written informed consent; a signedinformed consent must be obtained prior to any study-specific procedures

Exclusion Criteria:

• Known congestive heart failure (CHF) (active disease or history of)

• Left ventricular ejection fraction less than 55%

• Planned concurrent administration of other investigational agents

• Planned subsequent therapy with a human epidermal growth factor receptor 2 (HER2)-directed treatments (trastuzumab, pertuzumab, trastuzumab emtansine [T-DM1]) orother anthracyclines besides doxorubicin

• Swallowing or absorption problems that might interfere with oral bioavailability ofsildenafil

• Known hypersensitivity to doxorubicin, sildenafil or any component of either agent

• Planned chronic nitrate or alpha blocker therapy

• Exclude persons who require ongoing administration of STRONG cytochrome P450, family 3, subfamily A, polypeptide 4 (CYP3A4) inhibitors and/or inducers; short periods ofexposure to CYP3A4 inhibitors will be allowed (i.e., exposure to aprepitant for threedays at the time of doxorubicin exposure)

• Other relative contraindications to sildenafil as defined in the prescribinginformation:

• Myocardial infarction, stroke, or life-threatening arrhythmia within the last 6months

• Coronary artery disease causing unstable angina

• Resting hypotension (blood pressure [BP] < 90/50) or hypertension (BP > 170/110)despite appropriate treatment

• Known retinitis pigmentosa

• Persisting or anticipated toxicity from prior therapy that might confound attributionof on-study adverse events (AEs)

• Pregnant or nursing

• Known hearing loss

• History of priapism when exposed to PDE5 inhibitors (sildenafil, vardenafil,tadalafil)

• Other condition(s) that in the opinion of the investigator might compromise theobjectives of the study