Pomalidomide Treatment in Patients With Kaposi Sarcoma

Inclusion Criteria: * Participant is able to understand and willing to sign a written informed consent document * Participants must have histologically or cytologically confirmed cutaneous KS. Participants must have measurable disease with a minimum of five bi-dimensionally measurable KS cutaneous marker lesions. If fewer than five bi-dimensionally measurable marker lesions are available, the total surface area of the marker lesion(s) must be \>= 700 mm\^2 * Participants must have documentation of HIV status * If HIV negative, documentation of a negative HIV rapid test within 21 days before enrollment into OPEN Step-1 (Treatment Assignment - Registration Step). * If HIV positive, documentation of HIV-1 infection by means of any one of the following: * Documentation of HIV diagnosis in the medical record by a licensed health care provider * Documentation of receipt of antiretroviral therapy (ART) (at least two different medications that do not constitute a prescription for pre-exposure prophylaxis \[PrEP\]) by a licensed health care provider. Documentation may be a record of an ART prescription in the participant's medical record, a written prescription in the name of the participant for ART, or pill bottles for ART with a label showing the participant's name * Any licensed HIV screening antibody and/or HIV antibody/antigen combination assay confirmed by a second licensed HIV assay such as a HIV-1 Western blot confirmation or HIV rapid multi-spot antibody di…