Year: 2004
Type: article
Study design: Case Report
Abstract: econd hematopoietic malignancies have been reportedafter treatment for a variety of human lymphomas and leukemias.Often the 2nd neoplasm will have a higher grade and exhibit a more aggressive clinical course.For example, splenic marginal zone lymphoma, a disease with an indolent clinical course, can progress to large cell B-cell lymphoma with a more malignant clinical course in approximately 10% of cases. 1 The development of large-cell lymphoma in humans after chronic lymphocytic leukemia is called Richter's syndrome and occurs in approximately 3% of all cases of chronic lymphocytic leukemia.2 Survival in humans after the appearance of the large-cell lymphoma is less than 6 months despite aggressive treatment.An important question about the development of a 2nd malignancy is whether the 2nd tumor is derived from the same clone as the original or if it is a new primary malignancy.The former may be the result of selection of a more drug-resistant neoplasm and require alternative or more aggressive chemotherapy.In Richter's syndrome, most of the evidence suggests that the neoplastic cells comprising the chronic lymphocytic leukemia have the same clonal origin as those found in the large B-cell lymphoma that develops later. 2 Clonal relatedness between 2 tumors can be established either by demonstrating that both tumors have similarly rearranged immunoglobulin genes by Southern blotting or by sequencing the deoxyribonucleic acid (DNA) encoding the immunoglobulin hypervariable region and showing that both tumors have the same sequence.In the present case report, we describe a dog that presented initially with multicentric lymphoma.Treatment resulted in complete clinical remission from disease for approximately 3 months, at which time the dog re-presented with multiple myeloma.The dog's disease progressed rapidly, resulting in euthanasia after 6 weeks.We investigated the clonal relatedness of the 2 tumors by sequencing the immunoglobulin gene rearrangements in each.A 12-year-old 22-kg male neutered Shetland Sheepdog presented to the Veterinary Teaching Hospital at Colorado State University for weakness and lethargy.Physical exam revealed generalized lymphadenopathy, hepatomegaly and splenomegaly, and bruising on the ventral abdomen.Radiographs revealed a normal thorax, and abdominal ultrasound showed hepatomegaly, splenomegaly, and sublumbar
Authors: Robert C Burnett, Mary Kay Blake, Laura J Thompson, Paul R Avery, Anne C Avery
Institution: Colorado State University
Language: English
Subfield: Pathology and Forensic Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
Funder: Morris Animal Foundation
OpenAlex ID: W2001018340