Clinical outcome of nonnasal chondrosarcoma in dogs: thirty-one cases (1986-2003).

OBJECTIVE

To evaluate metastatic rate and survival times of dogs with chondrosarcoma of nonnasal bony sites treated by wide surgical excision.

STUDY DESIGN

Retrospective study.

ANIMALS

Dogs (n=31) with chondrosarcoma.

METHODS

Medical records were retrospectively reviewed to identify dogs with chondrosarcoma of bone in potentially surgically accessible sites. When complete information was not available in the medical record, owners and referring veterinarians were contacted by telephone to evaluate the course of disease and survival times. When possible, histopathologic diagnosis was confirmed by a single board certified pathologist and tumors were histologically graded.

RESULTS

Dogs treated by wide surgical excision (n=18) had a mean survival time of 3097 days and did not reach median survival time. Dogs untreated except for diagnostic biopsy (n =13) had a median survival time of 523 days and a mean survival time of 495 days. Method of treatment and tumor grade predicted survival time (P=.016 and P=.007, respectively). Metastatic rate was 28% for treated dogs and 15% for untreated dogs, with no significant difference between the 2 groups (P=.39).

CONCLUSIONS

Wide surgical excision significantly improves survival time for dogs with chondrosarcoma of nonnasal bony sites, but does not affect the likelihood of metastasis. Grade may be prognostic for survival.

CLINICAL RELEVANCE

Surgical excision benefits dogs with chondrosarcoma and can result in prolonged survival times. Metastasis still occurs in approximately 1 of 4 dogs even after surgical resection.