Peer-reviewed veterinary case report
Larger mammary tumors in dogs are more likely to be cancerous
By Gedon, Julia et al.·Published in Veterinary and comparative oncology·2021·Small Animal Clinic Hofheim, Germany·View original on PubMed →
PetCaseFinder translated the abstract of this peer-reviewed paper into plain English so pet owners can read it. We do not publish original research — every detail traces back to the citation above. How we work →
Original publication title: Canine mammary tumours: Size matters-a progression from low to highly malignant subtypes.
- Species:
- dog
Plain-English summary
A 9-year-old female dog with mammary tumors was studied to see if the size of the tumors affected how dangerous they were. It was found that larger tumors were more likely to be malignant (cancerous) compared to smaller ones, with an average size of 1.94 cm for malignant tumors versus 0.90 cm for benign ones. The research showed that as the tumors grew, they could progress from less harmful to more harmful types. This means that even a small increase in tumor size could significantly impact the dog's health and treatment options.
People also search for: dog mammary tumor size · malignant vs benign tumors in dogs · dog cancer treatment options
Abstract
The purpose of this study was to evaluate a possible association between mammary tumour size and increasing degree of malignancy. Data of 625 dogs with a total of 1459 mammary tumours were analysed retrospectively. 80.3% dogs were intact, mean age at diagnosis was 9.7 ± 2.5 years, 75.8% were pure breed dogs. Median body weight was 20.0 kg. Malignant tumours (n = 580) were significantly larger than their benign counterparts (1.94 cm vs 0.90 cm in mean, respectively; P ≤ .0001), resulting in a positive correlation between increasing tumour size and a change from benign to malignant (P ≤ .0001; r = 0.214). When malignant tumours were grouped into four degrees of increasing malignancy (complex/simple/solid/anaplastic carcinomas) a significant positive correlation between increasing tumour size and more malignant tumour degree (P ≤ .0001; r = 0.195) could be demonstrated. In a number of cases, highly malignant tumours were found to arise within less malignant lesions, supporting the concept of a further progression within the malignant tumour subtypes. In patients with multiple tumours, mean tumour sizes for malignant tumours were significantly smaller compared to patients with only one tumour (1.67 vs 2.71 cm in mean, respectively; P < .0001). These findings suggest that mammary tumours progress not only from benign to malignant but also from low to highly malignant. An increase in diameter of only a few millimetres may therefore have a big impact on the patient's outcome.
Find similar cases for your pet
PetCaseFinder finds other peer-reviewed reports of pets with the same symptoms, plus a plain-English summary of what was tried across them.
Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/32945086/