Prospective Study of Lymphoproliferative Diseases

Inclusion Criteria: * All subjects regardless of age, sex or HIV serostatus must have biopsy-proven non-Hodgkin's (NHL), including primary effusion lymphoma, Hodgkin's lymphoma (HD) or other lymphoproliferative disorder (e.g., Castleman's disease) with measurable or evaluable stage I through IV disease. \[Note: Lymphomas will be categorized on the basis of current WHO classification scheme, but it is recognized that initial pathological categorization at time of study enrollment will more than likely be classified or graded as low-, intermediate-, or high-grade lymphoma by Working Formulation criteria. This is the current standard of practice in Kenya.\] * All subjects must receive some form of systemic chemotherapy. Subjects not receiving chemotherapy of any kind are not eligible. Subjects must not have had any prior chemotherapy for lymphoma. * Subjects may have received prior radiotherapy for localized stage I or stage II disease that is clearly documented to have progressed beyond initial radiotherapy ports. * All subjects must give written informed consent to participate on study. In Kenya, a child is considered \< 18 years of age and an adult ≥ 18 years of age. All children will have their parental or legal guardian provide consent.. Children between the ages of 7 and \< 18 years old should be given the opportunity to provide their assent. For children between the ages of 7 and 11 years old this should be done using the parental consent form assent statement. For children \> 11 years old assent should be documented using the IRB approved assent form. Exclusion Criteria: * Subjects who do not fulfill the criteria as listed in Sections 3.1.1 through 3.1.4 are ineligible. * Subjects who received prior chemotherapy (i.e., first-line treatment) or are not receiving any chemotherapy for their non-Hodgkin's (NHL) or Hodgkin's lymphoma (HD) are ineligible.