Search Results

You are looking at 11 - 14 of 14 items for

  • Author or Editor: Jose A. Ramos-Vara x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract

Objective—To determine expression of folate receptors (FRs) and folate uptake in multicentric lymphomas in dogs.

Sample—10 dogs with histopathologically confirmed multicentric lymphoma and 20 archival lymph node biopsy specimens from dogs with multicentric lymphoma.

Procedures—Multicentric lymphomas in 10 dogs were prospectively evaluated for FR expression by use of immunohistochemical analysis and for in vivo folate uptake by use of nuclear scintigraphy. Dogs with FR-expressing tumors were eligible for FR-targeted chemotherapy. Twenty archival lymphoma biopsy specimens were also evaluated with immunohistochemical analysis.

Results—FRs were not detected with immunohistochemical analysis in lymph node samples obtained from the 10 dogs or in archival biopsy specimens. However, nuclear scintigraphy revealed uptake of radioactive tracer in 6 of 10 dogs. Five of these 6 dogs were treated with an FR-targeted chemotherapeutic agent; results of treatment were complete remission in 1 dog, stable disease in 2 dogs, and progressive disease in 2 dogs. Treatment-related toxicoses generally were mild.

Conclusions and Clinical Relevance—This study provided strong evidence for folate uptake in a substantial portion of multicentric lymphomas of dogs and indicated the antitumor activity of FR-targeted chemotherapeutics for these cancers. Use of FR-targeted chemotherapeutics may be promising for the treatment of FR-expressing multicentric lymphomas in dogs. Further studies are needed to determine reasons for lack of immunoreactivity to currently identified anti-FR antibodies and to develop improved methods for detecting FRs in lymphomas of dogs.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To assess the diagnostic utility of transurethral cystoscopic biopsy in dogs with histologically confirmed transitional cell carcinoma (TCC) of the urinary bladder and urethra.

Design—Retrospective case series.

Animals—92 dogs with histologically confirmed TCC.

Procedures—Information on sex, breed, neuter status, body weight, tumor location, biopsy method, number of biopsy procedures, experience level of clinician performing biopsy, and quality of biopsy sample was obtained from medical records. The association of variables with likelihood of achieving a diagnostic-quality biopsy sample was evaluated by use of logistic regression.

Results—If used as the initial biopsy method, cystoscopic biopsy samples were of diagnostic quality in 65% of male dogs and 96% of female dogs with histologically confirmed TCC. Cystoscopic biopsy samples were significantly more likely to be of diagnostic quality in female dogs than in male dogs.

Conclusions and Clinical Relevance—Cystoscopic biopsy is an effective method to obtain biopsy samples in dogs with TCC of the bladder and urethra. Cystoscopy is more likely to produce a diagnostic-quality biopsy sample in female dogs with TCC than in male dogs with TCC. Cystoscopy should be considered as a primary means of biopsy in male and female dogs with masses of the urinary bladder or urethra.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine uroplakin III expression, potential etiologic factors, biological behavior, and treatment response of transitional cell carcinoma (TCC) in the abdominal wall (ABWTCC) in dogs.

Design—Retrospective case series.

Animals—24 dogs with TCC of the urinary tract that also had histopathologic confirmation of ABWTCC.

Procedures—Medical records, histologic slides, radiographs, and ultrasonographic images of dogs with ABWTCC between July 1, 1985, and December 31, 2010, were reviewed. In available tissue specimens, immunohistochemistry was used to detect uroplakin III expression in the ABWTCC and in the primary tumor.

Results—The ABWTCC lesions ranged from < 2 to > 20 cm in diameter. Uroplakin III was expressed in 19 of 20 primary tumors and 17 of 17 ABWTCCs. Transitional cell carcinoma in the abdominal wall developed significantly more often in dogs that had undergone cystotomy (18/177 [10.2%]) than in those that had not (6/367 [1.6%]). In 1 dog that had not undergone cystotomy, TCC had invaded through the urinary bladder wall and spread down the median ligament to the abdominal wall. None of 18 dogs that received anticancer drugs had remission of the ABWTCC once clinically detected; median survival time after ABWTCC detection was 57 days (range, 0 to 324 days).

Conclusions and Clinical Relevance—Results suggested that ABWTCC is uncommon, but once TCC becomes established and clinically detectable in the abdominal wall, it carries a poor prognosis. It is crucial to minimize risk of TCC seeding at surgery. Percutaneous sampling of TCC should be avoided. Uroplakin III is commonly expressed in ABWTCC.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate the clinical and pathologic characteristics of mammary duct ectasia in dogs.

Design—Retrospective study.

Animals—51 dogs with mammary duct ectasia.

Procedure—Information regarding body condition, history, number and location of affected mammary glands, appearance of lesions, surgical treatment, nonsurgical treatment, and evidence of recurrence or development of mammary neoplasia was obtained from surveys sent to referring veterinarians. Results of information from examination of histologic sections and referring veterinarians were evaluated for all mammary duct ectasia biopsies performed between 1992 and 1999.

Results—Duct ectasia was the primary diagnosis in 51 of 1,825 (2.8%) mammary biopsy specimens and comprised 48% of nonneoplastic mammary diseases. Affected dogs were evenly distributed over a range of 1 to 13 years of age, with a mean age at the time of diagnosis of 6.1 ± 3.1 years. All dogs were female (31 sexually intact, 20 spayed); 10 of 26 had whelped. Duct ectasia was described as nodular (26 dogs), cystic (13), and multiglandular (11) and located in caudal (31) more often than cranial (14) or middle glands (10). Ectasia recurred in 3 dogs. One dog had a history of previously excised mammary adenocarcinoma; another subsequently developed mammary carcinoma.

Conclusions and Clinical Relevance—Duct ectasia affected mature, sexually intact and spayed female dogs over a wide age range. Certain breeds were affected more commonly than expected. Increased risk for mammary neoplasia was not evident. Duct ectasia should be considered as a cause for mammary enlargement, especially in young dogs or when its cystic nature is evident. Mastectomy is usually curative, and neoplasia should be ruled out in dogs with ectasia. (J Am Vet Med Assoc 2001;218:1303–1307)

Full access
in Journal of the American Veterinary Medical Association