Mammary tumor recurrence in bitches after regional mastectomy.
OBJECTIVE
To investigate the histologic diagnosis and incidence of new mammary tumor growth in the remaining mammary chain tissue after regional mastectomy.


METHODS
Prospective clinical study.


METHODS
Female dogs (n=99) that had excision of a single mammary tumor.


METHODS
Female dogs that had regional mastectomy to remove a single tumor were followed for >or=1 year postoperatively. Data regarding tumor type, tumor recurrence, and development of metastasis were recorded.


RESULTS
Fifty-seven (58%) dogs developed a new tumor in the ipsilateral mammary chain after the 1st surgery; 77% had repeat surgery. There was no significant correlation between the time to new tumor development and the histologic diagnosis for the 1st and 2nd tumor types. In 31 dogs, the histologic diagnosis for initial and subsequent tumors was identical and there was a significant correlation such that dogs with an initial malignant tumor are likely to develop another malignant tumor (P=.0089). The histologic classification of the new tumor was likely to be malignant if it was located close to the side where the initial tumor had been removed (P=.026).


CONCLUSIONS
Our results show that 58% of dogs developed a new tumor in the remaining mammary glands of the ipsilateral chain after regional mastectomy for removal of a single tumor.


CONCLUSIONS
This should be taken into account when deciding on the surgical management (radical or regional mastectomy) in dogs with single mammary tumors.
Stratmann
Nina
N
Clinic for Obstetrics, Gynaecology and Andrology of Large and Small Animals, Justus-Liebig-University, Giessen, Germany. N.Stratmann@gmx.de
Failing
Klaus
K
Richter
Andreas
A
Wehrend
Axel
A
D000818:Animals; D018572:Disease-Free Survival; D004283:Dog Diseases / Q000601:surgery*; D004285:Dogs; D005260:Female; D005500:Follow-Up Studies; D015994:Incidence; D015674:Mammary Neoplasms, Animal / Q000473:pathology / Q000601:surgery*; D015409:Mastectomy, Radical / Q000009:adverse effects / Q000379:methods / Q000662:veterinary; D015412:Mastectomy, Segmental / Q000009:adverse effects / Q000379:methods / Q000662:veterinary*; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology / Q000662:veterinary*; D011446:Prospective Studies; D012086:Reoperation / Q000379:methods / Q000662:veterinary*; D013997:Time Factors; D016896:Treatment Outcome