The goal of this study is to gain new knowledge about genetic risk factors thta may affect the development of mucositis, the chemotherapy-induced sores in the mouth and esophagus following HSCT. The study seeks to understand if different forms of genes result in an increased risk of sores in the mouth and esophagus.

Subjects will be provided with a saliva collection kit which can be used at home. Subjects will return the collection kit in a paid, pre-addressed mailer to the laboratory at Biomodels. The laboratory will isolate and store the DNA located in the cells of the saliva. A portion of this DNA will be used to analyze the different forms of genes. The remainder of the DNA will be destroyed when this study is completed. Biomodels will not be provided with patient identifiers.

The investigators will also collect information from medical records, including information about diagnosis, treatment, stem cell transplantation and post-transplantation outcomes. This information will be de-identified.

Inclusion Criteria:

• Have given informed consent to submit a sample of saliva for DNA isolation and SNP analysis
• Have undergone autologous HSCT for treatment of Hodgkin's or non-Hodgkin's lymphoma or multiple myeloma at the Dana-Farber Cancer Institute from 1/1/2006 through 6/30/2010
• Have medical records identifying whether the participants did or did not develop severe mucositis

Exclusion Criteria:

• Received Palifermin (Kepivance) prior to their conditioning regimen

Subjects who have undergone autologous HSCT for Hodgkin's or non-Hodgkin's lymphoma or multiple myeloma at Dana Farber Cancer Institute from 1/1/2006 through 6/30/2010.