Virotherapy and Natural History Study of KHSV-Associated Multricentric Castleman's Disease With Correlates of Disease Activity

This study will gain information about a rare disorder called KSHV-associated multicentric Castleman's disease (MCD). KSHV, a virus, causes several kinds of cancer, including some forms of MCD. KSHV stands for the Kaposi's sarcoma herpes virus, also called human herpes virus-8, or HHV-8. Researchers want to understand the biology of KSHV-MCD to identify how this disease causes illness and to find ways to treat it. There is no standard therapy effective for all cases of KSHV-MCD. The disease is often fatal, and about half the people who have it die within 2 years of diagnosis.

Patients ages 12 and older may be eligible for this study. Participation entails more drawing of blood and having repeated tumor biopsies than if patients received treatment in a non-research setting. Researchers would like to learn more about the relationship of KSHV and Castleman's disease symptoms, and they want to obtain at least three biopsies in this study.

There are some side effects of experimental therapy that patients may take for KSHV-MCD. Zidovudine, or Retrovir(Registered Trademark), is used at a high dose. It is given orally or through a vein, four times daily, for 7 days or longer. Zidovudine can cause nausea, vomiting, decreased bone marrow function, and decreased blood counts. Combined with valganciclovir, or Valcyte(Trademark), it is likely to be more toxic to bone marrow. Valganciclovir can cause problems with bone marrow function, leading to low blood counts, sterility, and defects in a fetus. Combined with zidovudine, valganciclovir may cause more toxicity to the bone marrow. It is given twice daily for 7 days or longer. Bortezomib, or Velcade(Trademark), is given for a few seconds by a rapid push through a needle into the vein. It is given twice weekly for four doses and then stopped for 1 week. Bortezomib can sometimes cause low blood pressure; it also can cause gastrointestinal problems and a low blood platelet count. Rituximab and liposomal doxorubicin are drugs given by a catheter into a vein. Interferon-alpha is given by injection into the skin. Those drugs are not experimental, but their use in Castleman's disease is experimental.

Some patients may be treated with a combination of chemotherapy followed by interferon-alpha. Interferon-alpha is infected into the skin by a needle. The natural form of interferon is produced by the body and helps to control viral infections. KSHV decreases the effect of the body's interferon, and the researchers want to see if giving higher doses of interferon will help to control KSHV infection.

A positron emission tomography (PET) scan, for research purposes only, may be done up to three times a year. A radioactive sugar molecule called fluorodeoxyglucose, or FDG, is used. It is believed that activated lymphocytes that may be found in patients' disease might use more FDG because these cells burn more glucose fuel. Children younger than 18 years will not have PET scan done.

This study may or may not have a direct benefit for participants. However, detailed assessments made throughout the study may provide information to help the doctors treat KSHV-MCD better.