Evaluation of primary re-excision after recent inadequate resection of soft tissue sarcomas in dogs: 41 cases (1999-2004).
OBJECTIVE
To determine the efficacy of primary re-excision alone for treatment of soft tissue sarcomas after recent incomplete resection, the frequency and clinical importance of detecting residual tumor in resected scars, and prognostic factors associated with the procedure.


METHODS
Retrospective case series.


METHODS
41 dogs.


METHODS
Medical records of dogs that had undergone recent incomplete excision of a soft tissue sarcoma at a referring veterinary practice and subsequent re-excision of the scar at the Colorado State University Veterinary Medical Center were reviewed. Owners and referring veterinarians were contacted for follow-up information. Slides from re-excised specimens were reviewed. Dogs that underwent radiation therapy after the re-excision procedure were excluded.


RESULTS
41 dogs met the inclusion criteria, and long-term follow-up information was available for 39 dogs. Median follow-up time was 816 days. Local recurrence of tumor developed in 6 of 39 (15%) dogs, and distant metastasis occurred in 4 of 39 (10%) dogs. Healthy tissue margins of 0.5 to 3.5 cm were achieved at re-excision. Residual tumor was identified in 9 of 41 (22%) resected scars. No tumor-, patient-, or treatment-related variables were associated with local recurrence except for the presence of liposarcoma or fibrosarcoma or whether fine-needle aspiration had been performed prior to surgery.


CONCLUSIONS
After incomplete resection of soft tissue sarcomas, resection of local tissue should be performed, even if excisable tissue margins appear narrow. A long-term favorable prognosis is achievable without radiation therapy or amputation. The presence of residual tumor in resected scar tissue should not be used to predict local recurrence.
Bacon
Nicholas J
NJ
Animal Cancer Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
Dernell
William S
WS
Ehrhart
Nicole
N
Powers
Barbara E
BE
Withrow
Stephen J
SJ
D000818:Animals; D003131:Combined Modality Therapy; D004283:Dog Diseases / Q000473:pathology / Q000601:surgery* / Q000628:therapy; D004285:Dogs; D005260:Female; D005500:Follow-Up Studies; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000662:veterinary; D009367:Neoplasm Staging / Q000662:veterinary; D018365:Neoplasm, Residual / Q000473:pathology / Q000601:surgery / Q000628:therapy / Q000662:veterinary*; D011379:Prognosis; D018714:Radiotherapy, Adjuvant / Q000662:veterinary; D012086:Reoperation / Q000662:veterinary; D012189:Retrospective Studies; D012509:Sarcoma / Q000473:pathology / Q000601:surgery / Q000628:therapy / Q000662:veterinary*; D012983:Soft Tissue Neoplasms / Q000473:pathology / Q000601:surgery / Q000628:therapy / Q000662:veterinary*; D016896:Treatment Outcome