|ROMANO, FRANK - Tufts University|
|HEINZE, CAILIN - Tufts University|
|BARBER, LISA - Tufts University|
|MASON, JOEL - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|FREEMAN, LISA - Tufts University|
Submitted to: Journal of Veterinary Internal Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/21/2016
Publication Date: 7/1/2016
Citation: Romano, F.R., Heinze, C.R., Barber, L.G., Mason, J.B., Freeman, L.M. 2016. Association between body condition score and cancer prognosis in dogs with lymphoma and osteosarcoma. Journal of Veterinary Internal Medicine. 30(4):1179-1186. https://doi.org/10.1111/jvim.13965.
Interpretive Summary: Obesity in humans is thought to promote the risk of developing several types of cancer as well as increase tumor aggressiveness and the likelihood of cancer recurrence. It is unknown whether the same phenomenon exists in dogs with cancer. A retrospective study was conducted in 324 pet dogs that had presented with two of the most common varieties of canine cancer: osteosarcoma and lymphoma. Obesity did not increase the risk of tumor progression, nor did it shorten survival time. However, among the dogs that were underweight at the time of lymphoma diagnosis, a shorter survival time was observed. Thus, in these two common types of canine cancer, obesity at the time of diagnosis does not seem to adversely affect the course of the cancer.
Technical Abstract: Background: In humans and rodents obesity appears to promote some cancers by increasing incidence, tumor aggressiveness, recurrence, and mortality. However, the relationship between obesity and cancer in dogs has not been thoroughly evaluated. Hypothesis/Objectives: We examined whether body condition score (BCS) at the time of lymphoma (LSA) or osteosarcoma (OSA) diagnosis in dogs is predictive of survival time (ST) or progression-free interval (PFI). We hypothesized that an overweight body state at the time of cancer diagnosis would be associated with negative outcomes. Animals: Dogs with LSA (n = 270) and OSA (n = 54) diagnosed and treated between 2000 and 2010. Methods: Retrospective case review. Signalment, body weight, BCS, cancer diagnosis and treatment, relevant clinicopathologic values, and survival data were collected. Dogs were grouped by BCS (underweight, ideal, and overweight) and ST and PFI were compared. Results: Overall, 5.5% of dogs were underweight, 54.0% were ideal weight, and 40.4% were overweight at diagnosis. Underweight dogs with LSA had shorter ST (P = 0.017) than ideal or overweight dogs. BCS was not associated with ST for OSA (P = 0.518). Progression-free interval did not differ among BCS categories for either cancer. Conclusions and Clinical Importance: Obesity was not associated with adverse outcomes among dogs with LSA or OSA in this retrospective study; however, being underweight at the time of diagnosis of LSA was associated with shorter survival. More research is needed to elucidate the relationship between excessive body weight and cancer development and progression in dogs.