To evaluate complication rates for various types of mastectomy procedures, identify factors associated with an increased risk of complications, and determine the consequences of such complications.
140 female dogs that underwent 154 separate mastectomy procedures to treat mammary gland tumors.
Medical records of dogs in the Penn Vet Shelter Canine Mammary Tumor Program from July 2009 to March 2015 were reviewed. Data regarding signalment, tumor characteristics (ie, number and size, benign or malignant, and bilateral or unilateral), mastectomy type, anesthesia time, concurrent ovariohysterectomy or ovariectomy, surgeons’ qualifications, antimicrobial administration after surgery, postoperative placement of surgical drains, and complications (seroma, abscess, dehiscence, or infection) were collected. Complications that required hospitalization were recorded. Fisher exact tests were used to evaluate associations between variables of interest and complications. Multivariable analysis was used to identify factors independently associated with an increased risk of complications.
Complication rate following all mastectomy procedures was 16.9% (26/154); of these, 9 (34.6%) required hospitalization. High body weight, undergoing bilateral mastectomy, and postoperative antimicrobial administration were associated with significantly increased odds of complications. The odds of complications associated with postoperative antimicrobial administration, however, varied according to mastectomy type; dogs undergoing chain mastectomy that did not receive antimicrobials postoperatively had the highest odds of developing complications. Dogs undergoing concurrent ovariohysterectomy or ovariectomy had significantly decreased odds of complications.
CONCLUSIONS AND CLINICAL RELEVANCE
Previously spayed dogs with a large body size that underwent the most extensive mastectomy procedures had increased odds of having postoperative complications.
Objective—To determine the biological behavior of
liposarcomas in dogs and identify clinical signs, the
effect of treatment on survival time, and potential
Animals—56 dogs with histologically confirmed liposarcoma.
Procedure—Information was obtained on signalment,
tumor size, location of the tumor, stage of disease,
remission duration, overall survival time, cause
of death, type of surgery (incisional biopsy, marginal
excision, or wide excision), and any additional treatments
Results—Surgery consisted of incisional biopsy in 6
dogs, marginal excision in 34, and wide excision in 16.
Twenty-five dogs had histologic evidence of tumor
cells at the surgical margins and 28 did not (status of
the margins was unknown in 3 dogs). Twelve of 43
dogs had local recurrence. Median survival time was
694 days, and the only factor significantly associated
with survival time was type of surgery performed.
Median survival times were 1,188, 649, and 183 days,
respectively, for dogs that underwent wide excision,
marginal excision, and incisional biopsy. Factors that
were not found to be significantly associated with
survival time included tumor size, status of the margins,
tumor location, and histologic subtype.
Conclusions and Clinical Relevance—Results suggest
that in dogs, liposarcomas are locally invasive
neoplasms that rarely metastasize and occur primarily
in appendicular or axial locations and that wide excision
is preferred to marginal excision when feasible.
(J Am Vet Med Assoc 2004;224:887–891)
Objective—To identify risk factors for development of sepsis in dogs treated with chemotherapeutics and to evaluate the impact of sepsis on outcome.
Animals—Client-owned dogs with various cancers undergoing standard chemotherapeutic treatment at the University of Pennsylvania veterinary hospital.
Procedures—39 dogs with sepsis (cases) were identified through a search of the medical record database. Controls (n = 77) were randomly selected from dogs admitted during the same time period. Variables analyzed included patient demographics, tumor type, stage, remission status, treatment phase, chemotherapeutics used, and outcome.
Results—Dogs that weighed less and dogs with lymphoma were significantly more likely to become septic, compared with larger dogs or dogs with solid tumors. Septic dogs were also significantly more likely to have received doxorubicin (odds ratio [OR], 12.5; 95% confidence interval [CI], 2.4 to 66.0) or vincristine (OR, 9.0; 95% CI, 1.6 to 52.0) than controls. Of the 39 cases, 28 (71.8%) were in the induction phase of their protocol, and 19 of 39 (48.7%) became septic after receiving the chemotherapeutic drug for the first time. Median survival time of the cases (253 days) was not significantly different from that of the controls (371 days).
Conclusions and Clinical Relevance—Dogs that weighed less were at increased risk for chemotherapy-induced sepsis. Tumor type and chemotherapeutic drug used were also important risk factors. These results may lead to the implementation of prophylactic measures, especially when doxorubicin or vincristine is used in the induction phase in small dogs with lymphoma.
Objective—To evaluate time to first recurrence (TFR)
and overall survival in cats with presumed vaccine-associated
sarcomas (VAS) treated with excision.
Animals—61 cats with presumed VAS.
Procedure—Medical records of cats that received
excision as the only initial treatment for presumed
VAS were reviewed to evaluate prognosis. Overall
survival curves and TFR were determined.
Results—Median TFR was 94 days. Median TFR for
tumors treated with excision performed at a referral
institution (274 days) was significantly longer than that
for tumors excised by a referring veterinarian (66 days).
Radical first excision yielded significantly longer median
TFR (325 days) than did marginal first excision (79
days). Cats with tumors located on the limbs had
longer median TFR (325 days) than cats with tumors
located in other sites (66 days). Median overall survival
time was 576 days. Significant differences in survival
times between groups were not detected. Few cats
(13.8%) receiving only surgical treatment had longterm
(> 2 years) survival.
Conclusions and Clinical Relevance—Radical first
excision of presumed VAS is essential for extended
TFR. Current recommendations for vaccination of the
distal portions of the extremities are appropriate,
because this practice permits radical excision of
tumors (amputation) that develop at vaccination sites;
however, surgery alone is seldom curative. ( J Am Vet
Med Assoc 2000;216:58–61)
Objective—To determine sensitivity and specificity of
physical examination, fine-needle aspiration, and needle
core biopsy of the regional lymph nodes for evidence
of metastasis in dogs and cats with solid
Animals—37 dogs and 7 cats.
Procedure—Regional lymph nodes were evaluated
by means of physical examination (palpation), fineneedle
aspiration, and needle core biopsy. Results
were compared with results of histologic examination
of the entire lymph node, the current standard.
Results—Tumors included 18 sarcomas, 16 carcinomas,
7 mast cell tumors, and 3 other tumors.
Carcinomas were more likely to have metastasized to
the regional lymph node (7/16 animals) than were sarcomas
(2/18). Sensitivity and specificity of physical
examination were 60 and 72%, respectively.
Sensitivity and specificity of cytologic examination of
fine-needle aspirates were 100 and 96%, respectively.
Sensitivity and specificity of histologic examination
of needle core biopsy specimens were 64 and 96%,
Conclusions and Clinical Relevance—Results suggested
that fine-needle aspiration may be a sensitive
and specific method of evaluating the regional lymph
nodes in dogs and cats with solid tumors, because
results correlated well with results of histologic examination
of the entire lymph node. Physical examination
alone was not a reliable method and should not be
used to decide whether to aspirate or biopsy the
regional lymph nodes. (J Am Vet Med Assoc
Objective—To establish the maximum tolerated dose of Clostridium novyi–NT spores in tumor-bearing dogs and evaluate spore germination within tumors and tumor response.
Animals—6 client-owned dogs.
Procedures—A standard dose-escalation study was planned, with maximum tolerated dose defined as the highest dose at which 0 or 1 of 6 dogs had dose-limiting toxicoses (DLT). Dogs received 1 dose of C novyi–NT spores IV. Toxicoses were graded and interventions performed according to specific guidelines. Grade 3 or higher toxicosis or any toxicosis combination that substantially affected patient status was considered DLT. Clinical response was measured by use of response evaluation criteria in solid tumors at 28 days.
Results—The first 2 dogs had DLT. The dose was decreased. Two of the next 4 dogs had DLT; therefore, dose administration was stopped because the study endpoint had been reached. The most common toxicosis was fever (n = 6 dogs). Two dogs developed abscesses (1 within a nasal carcinoma and 1 splenic abscess) attributable to C novyi–NT infection; both required surgical intervention. Clostridium novyi–NT was cultured from 1 of 6 tumors. Five dogs were available for response assessment (4 had stable disease; 1 had progressive disease).
Conclusions and Clinical Relevance—Results indicated that C novyi–NT can germinate within tumors of dogs. Toxicosis, although common and sometimes severe, was manageable with treatment. Further studies in dogs with superficial tumors may allow for continued dose escalation and provide information for use in clinical trials in veterinary and human oncology.