Bortezomib in Treating Patients With Relapsed or Refractory AIDS-Related Kaposi Sarcoma

Inclusion Criteria: * Adult patients with cutaneous AIDS-related biopsy-proven KS relapsed after or refractory to at least one other prior systemic therapy * Patients must have cutaneous KS lesion(s) amenable to biopsy (either one lesion \>= 12 mm or 3 \>= 4 mm) in addition to at least 5 lesions measurable for assessment; all of these lesions must not have been previously radiated * Must have been on stable anti-retroviral therapy for at least 12 weeks with a principal investigator (PI)-based or non-nucleoside reverse-transcriptase inhibitor (NNRTI)-based regimen of at least three drugs, with no intention to change the regimen for the duration of the study; patients who have a high likelihood of better HIV management with a new antiretroviral regimen should defer enrollment until the changes are in place and the new highly active antiretroviral therapy (HAART) regimen meets the 12 week criteria * Serologic documentation of HIV infection at any time prior to study entry, as evidenced by positive enzyme-linked immunosorbent assay (ELISA), positive western blot, or other Food and Drug Administration (FDA)-approved licensed HIV test, or a detectable blood level of HIV RNA * Women of child-bearing potential must have a negative pregnancy test within 72 hours before initiation of study drug dosing; post-menopausal women must be amenorrheic for at least 12 months to be considered of non-childbearing potential; male and female subjects of reproductive potential must agree to employ …